12/28 - 1:30am EST - Kentuckiana Winter Storm Number 2

Wednesday's winter storm didn't give much snow to folks in the Louisville area and instead confined heavy snow to areas of Southern Indiana. While differences in the models did exist over whether Louisville would get any accumulating snow or not, the overall situation was handled pretty well from a forecast standpoint. The highest snow report in NWS Louisville's coverage area was 7.2 inches in Washington County, IN while Louisville received a trace to a half inch.

The next storm on the heels of the last one is less than 24 hours away as a system arrives from the southwest and stays to our southeast as it moves through the region. This will start as some rain for the Louisville area but as colder air filters in we'll switch over to snow during the later evening hours. This exact time for switchover depends on how warm we get during the day tomorrow (lower 40's versus upper 30's makes a difference!) and how fast the cold air comes in. The 0z NAM that came in earlier tonight has about 3" for the city and after comparing this with other models I'm thinking this may be a number we'll see most commonly reported by Saturday morning in Louisville. Higher totals will be possible just a bit further north from Louisville.

But even as I say this there's a small fly in the ointment. The 3z RPM model is in and it has the possibility of 4-6" of snow just due east of the city and a few very small totals like this scattered throughout areas near the Ohio River. This suggests that totals closer to 4" might be more widespread than previously thought. You can click the RPM output on the left for a larger view. We've seen the trend of increasing snow totals today on the models and this run of the RPM just continues this. We'll need to watch for this trend tomorrow morning to see if other models catch on. Right now this isn't really a factor in my forecast since it's just one model. Below is my snow forecast map for the region. Realize that, like the last storm, a small shift in track or more/less cold air will change things for some folks drastically.

Also worth noting is that the Hyrdrometeorological Prediction Center (HPC) has us in a Slight Risk of a 4" snowfall (think of this like the Slight, Moderate, and High severe weather risks) while areas closer to Cincinnati are in a Moderate Risk. Expect to see Winter Weather Advisories being issued tomorrow for portions of Kentuckiana. There may also be a few Winter Storm Watches issued as well depending on if forecast amounts of 4" or more look to be more widespread. You can keep up with the latest on this storm tomorrow by following me on Twitter and Facebook. Good luck, snow lovers!

7/7 - 10:30pm - Massive Heat Wave Ends with Storms

Today capped off the longest, hottest stretch of weather in Louisville that most people can remember. Today's 106° high at Louisville International Airport was the hottest it's been since July 14th, 1936 when it got to 107°. That temperature is Louisville's all-time record high and if we didn't have as many clouds as we did this afternoon in the city we would have met or broken it. This ends nine days of 100°+ weather, which is the third-longest stretch of triple digits ever recorded according to NWS Louisville.

Storms that will develop tomorrow will be ushering in cooler temperatures, which is welcome news! The bad part is that some of these storms may be severe due to the incredible amount of energy they'll have at their disposal from all the heat. Temperatures in the mid 90's tomorrow with sunshine and high humidity will power an awful lot of instability, or the tendency for air parcels to rise and create thunderstorms. A cold front sinking down from the north that will be stalling out once it passes just to our south will be the focus for storm chances starting tomorrow in the early afternoon in Louisville and lasting through Monday morning.

The main threats from these storms will be wind and hail, but there could also be a threat for some rotating storms too. While winds don't look favorable for any sort of big tornado problems tomorrow, a couple of these rotating storms may get just enough juice to put down a brief spin-up. EHI values in the adjacent image take into account both instability and helicity, which is a product of wind shear. The elevated values you see are powered mostly by instability and just a little bit of helicity, so again, winds aren't that favorable here. The Louisville area is no stranger to summertime tornadoes as you may remember a series of four of them that touched down in late June of last year.

Given the chances for some severe wind and hail tomorrow, the Storm Prediction Center has issued a 15% Slight Risk area for Kentucky. A better chance for severe weather (30%) exists closer to the East Coast where upper-level winds will be stronger as a trough digs down a bit into that area.

5/24 - 12:35am CDT - We're in... Iowa?

We didn't think we'd be in Iowa tonight. The storms that formed yesterday (Wednesday) rushed eastward as the cold front in the region decided to push further east than expected. Unfortunately none of these storms really did much because they formed in a linear fashion and didn't have the moisture necessary to get too severe. One of the southern cells in the line just west of Omaha, Nebraska managed to be isolated for a while and generated a wall cloud that triggered a tornado warning. Our only option in this environment was to cross the Missouri River in Omaha and wait for the storms to come to us because it would not be good to have the storms outrun us while trying to find a way across the river. The storms slowed down and died out pretty much at that point so we threw in the towel for the day.

Tomorrow will likely be a travel day back to Kansas or Southern Nebraska as we await Friday's potential chase setup. Storms tomorrow will be up near the Great Lakes in Wisconsin and Michigan and we just don't chase there due to the distance from the Plains and lack of good chase environment up there. Strong capping should keep storms from going up in the central and southern Plains, but we'll keep an eye on that in case that changes. Friday's setup may be decent if capping aloft doesn't ruin it. A deepening trough out in California and hopefully some better moisture return from the Gulf of Mexico should create potential for severe weather. A strengthening low in Southeast Colorado/Southwest Kansas should provide ample surface wind support for rotating storms should this pan out as forecast. The Storm Prediction Center already has a 5% risk area for this in their 3-day severe weather outlook. I'm crossing my fingers that this setup will yield some good storms because Friday is my last day chasing in the Plains until late June!

Follow me on Twitter and Facebook for updates this week.

4/12 - 5pm - Louisville Heat Island Research

It's finished. Since January I've been working on a bit of research that seeks to explain roughly how much the urban heat island effect is skewing the temperatures at Louisville International Airport (KSDF) compared to the rest of the city. Even though I completed this paper for honors credit in my applied climatology class at Mississippi State, this is a project I've been wanting to undertake since my high school years. (See update at bottom of post)

Click here to read the report  [PDF format | 1.73 MB]

Louisville International Airport

As a kid growing up in Louisville, KY I realized through watching countless TV weathercasts and reading many weather discussions that the high and low temperatures at the airport were considerably warmer than the rest of the city. Louisville has a well-documented heat island region in the center and northern portions of town where the highest concentration of development is, and consequently the increased heat from this area greatly influences the official temperatures at Louisville International Airport. This wasn't always the case. For many years the official measurements were taken at the suburban National Weather Service office off of Smyrna Road in Louisville. These measurements were not as skewed by this effect because it is in an area of trees, vegetation, and suburban housing instead of airport apron, large swaths of roadway, and urban development. This research puts a degree number on how much these measurements at the airport are affected by the heat island.

The time was right back in January to start on this research because climate records from internet-connected personal weather stations around the city have now been available for quite a few years for a good comparison. Not only that, but I feel that I've come far enough in my weather education to do something like this without having holes in understanding block my path. This is research that deals with simple averages and simple data, but I feel that the simplicity makes it powerful. Limited data and manpower put some constraints on this research, but the end result is what I believe to be a good rough estimate. I do offer suggestions for future research, which could maybe lead to some changes in how records are being kept within the city. This is a matter I feel strongly about because these airport temperature measurements in my opinion are not representing the city well, and there's quite a bit of explanation about that inside the paper. Give it a read and tell me what you think in the comments section below!

UPDATE: Mark Jarvis, senior forecaster at NWS Louisville, emailed with information saying that the temperature sensor at KSDF was changed in June 2011 and apparently the anomaly between KSDF temperatures and those in surrounding areas is not as great as it once was due to this. A study will be conducted by the NWS this summer to see how the sensor is performing. This does not change the 2009-2010 data and results I obtained in my paper above.

3/22 - 4:30pm - Heavy Rain is Gone, but Warm Temps Remain!

Heavy Rain

Did you get drenched? I think we all did. The rain over the past 24 hours has been tremendous, especially across Mississippi as inches and inches have fallen from the pesky system that has been slowly churning through the Plains and now the South. Check out the estimated rainfall map from today below to see what I mean (the totals for West Tennessee are underdone but you get the picture of who saw some tremendous rainfall earlier today!) Most of the rain is now east of West Tennessee and North Mississippi, but a few showers remain and will continue this evening.

More rain will fall tomorrow afternoon as another piece of energy from the same system rotates around the Mid-South. The area in red with the directional arrow coming from it is called a vorticity max. Usually the area where rain and storms develop is east of the vort max as it moves along. Tomorrow's rain won't be as heavy as today's by any stretch of the imagination and it will be more of a scattered nature than today's washout. Once this rain is all said and done by Saturday morning we should be left with a very nice weekend and temperatures warming back up through the upper 70's across West Tennessee and North Mississippi.

The Big Picture

Let's zoom out more and look at the system that's been causing all of this rain as a whole. What we have is an upper-level low in the Plains that is slowly moving eastward. An upper-level low like this one is basically a ball of cold-air that gets cut off from its northerly source because the jet stream kicks north leaves whatever is in the base of the former trough behind. It moves slowly because the jet stream, which usually drives big weather features, is absent from the process after the low gets cut-off. The satellite and radar images coming in from area where the low is are striking... you can see very well the rotation of the low pressure center, which makes it look like a land-based hurricane.

The jet stream being way up north is also why it's been so warm lately. In the winter the jet stream usually dips down from Canada and brings cold air to the USA. Areas north of the jet stream remain cold due to the influence of an arctic air mass while to the south of it there is usually a warm, moist air mass. This winter and now into this spring the jet stream has not really come down from Canada to the eastern half of the nation. The West has had it come down a few times though, which meant snow and cold temperatures for the Pacific Northwest and even down through California. The reason the jet stream stayed so far north is that La Nina (colder than usual ocean temperatures off the coast of Peru) remained pretty consistent throughout the season. In an El Nino pattern, the jet stream comes down to the US with a vengeance.

Record Warmth

The above-average temperatures from this pattern will persist for quite a while it looks like. A cursory glance at some of the long-range models shows that the jet stream will remain somewhere close to this northerly position for the foreseeable future. With that said, comparing this year and month to years past is incredible. This March so far has been the warmest on record in Jackson, TN and Tupelo, MS and the second warmest in Memphis. Jackson is running 10.6 degrees above average for this March. Comparing the year so far to years past, this is the warmest year so far in Memphis and Tupelo, and the second warmest so far in Jackson. These are remarkable numbers and we'll likely see more of these records flash by as the warmth continues. A running list of how this year's heat compares to previous records is available from NWS Memphis.

3/14 - 11:55pm EDT - Record-Breaking Warmth

The warm weather we've been seeing across the region hit record-breaking levels this afternoon. Here is a list of some broken temperature records today:

Jackson, TN: High 84° | Previous Record 80°

Memphis, TN: High 82° | Previous Record 80°

Chattanooga, TN: High 83° | Previous Record 81°

Louisville, KY: High 82° | Previous Record 80°

Paducah, KY: High 82° | Previous Record 78°
Evansville, IN: High 82° | Previous Record 77°

Indianapolis, IN: High 81° | Previous Record 79°

Many other cities in came close to breaking records, especially in Alabama and Middle Tennessee. The ridge over the Eastern US that's funneling all the remarkably unseasonable temperatures into the area will stay put through the weekend, but a few shortwave disturbances aloft will bring storm chances to much of West Tennessee, North Mississippi, and even into Central Kentucky tomorrow and Friday. These storms will be more organized than the spotty ones that developed in eastern portions of West Tennessee and even up through Western Kentucky this afternoon. The crazy-warm temperatures are going to last at least another full week as this strong ridge stays put, so I think to say that spring (or even summer) has sprung before winter officially ended!

3/2 - 12:30am - Severe Weather Outbreak Likely

A potent severe weather setup looks likely this afternoon and evening for Tennessee, Kentucky, Alabama, Mississippi, and even parts of Indiana and Ohio. All the ingredients are coming together for what could be a sizable tornado outbreak in these areas, especially around Middle Tennessee and Central Kentucky, maybe extending into Indiana too. We've had severe weather in some of these places just earlier this week, but this setup looks to be even more potent than that. Cities like Louisville, Lexington, Cincinnati, Nashville, Bowling Green, KY, Huntsville, Jackson, TN, Tupelo, MS, Starkville, MS, and Birmingham need to be on the lookout today.

Risks and Timing

The Storm Prediction Center has outlined a Moderate Risk area for severe weather tomorrow in an expansive area of the South. This includes a 15% tornado risk. Storms will likely erupt early this morning as a warm front surges northward and bring a hail risk to West Tennessee while not-as-strong storms will affect the most of the remainder of Kentucky, Tennessee, and Mississippi. These storms shouldn't be a huge deal, but a few might reach severe limits.

A brief break in the action throughout the mid and late morning hours should provide enough recovery time for the atmosphere to recharge and re-fire storms around noon. These storms will try to get going in West Tennessee and Northeast Arkansas, but will gain strength as they hit areas of greater surface heating to the east. These are the storms that could be very bad in a lot of areas. The worst tornado threat throughout the afternoon will be in Central Kentucky and Middle Tennessee, but there's a secondary area that could have tornado problems in Northeast Mississippi into North Alabama if a little more low-level wind shear comes into play. The Storm Prediction Center's latest severe weather outlook seems to pick up on that secondary tornado risk area by extending the Moderate Risk down to East Mississippi and Alabama. Straight-line wind damage and hail will be possible throughout the South tomorrow, so even if you're not in an area where tornadoes will be likely you need to be on the lookout for severe storms. The storms should move out quickly tomorrow evening once the cold front accelerates southeastward through the region.

Details

The reason why Central Kentucky to Middle Tennessee will be the area for maximum tornado potential tomorrow is because of an alignment of a few factors. For one, the fastest upper-level winds will be centered right over this area tomorrow afternoon. When you couple that with almost southerly winds (may be a bit southwesterly at times), you get not only a high difference between wind speed aloft and at the surface, but also a difference in direction. This is called wind shear and it's crucial to sustaining a thunderstorm and allowing it to become strong enough for tornado development. The southerly winds at the surface will help what's called low-level wind shear, and that's usually a pretty big factor in who gets tornadoes.

These southerly winds will also be bringing in moist air from the Gulf, which is the fuel for these storms as they develop. While the best moisture will be over Mississippi, Alabama, and Tennessee tomorrow, it will still be ample for serious severe weather in Kentucky. This moisture will bring some serious atmospheric instability to the region. When you couple this instability with helicity (the tendency for the atmosphere to rotate), you get what's called the Energy Helicity Index (EHI). This is a decent indicator of where the best tornado ingredients will be, and as you can see on the left, the values are particularly high tomorrow across a pretty vast area from Mississippi through Kentucky. Supercells appear likely in Tennessee and Kentucky, but Northeast Mississippi may have more of a mixed supercell/squall line of storms scenario due to less wind shear. This could be an entirely linear squall line event across Northeast Mississippi/North Alabama tomorrow if wind shear under performs. While squall lines don't harbor as many strong tornadoes, it is still a very real threat that needs to be monitored.

Safety

Before severe weather

• Make sure your cell phone is charged in case you lose power
• Have flashlights with fresh batteries ready to go. Your cell phone should NOT be your primary flashlight
• Your NOAA Weather Radio/Cell phone alert app should be ready to alert you
• Make a central meeting location for family members should you lose communications after the severe weather passes

I've said before that I like iMapWeather Radio on the iPhone for weather alerts. This is not any sort of endorsement, but it is an app that I use and it just works.

When a Tornado Warning is issued for your area

• Get to the lowest level of your home, apartment, or office
• Stay away from windows and try to get to the center of the structure you're in
• Evacuate mobile homes and get to a safe, sturdy building immediately
• Make sure you are wearing sturdy shoes
• If you have time (have these ready to go before a warning is issued), put bicycle helmets on the kids and yourself. Quite a few deaths were caused by head trauma in last year's tornadoes.

Please heed ALL warnings. This is a dangerous severe weather setup that needs no playing around with.

1/25 - 6pm - MSU Forecast and a Look Back at Monday Morning's Storms

Another bout of severe weather is affecting the South as a powerful line of storms continues to push through Louisiana. These storms have spawned some tornadoes today across Louisiana and Texas while a Tornado Watch remains in effect for areas from Lake Charles, Louisiana to just south of Greenville, Mississippi. We'll be watching these storms as they track into eastern portions of Mississippi tomorrow morning. There's a chance they could be severe here in Starkville and the Golden Triangle, but the main threat should remain south of the area. Once these storms clear out we'll be left with a fantastic few days heading into the weekend. Find out more in your full forecast below:

from ABC 33/40 on Flickr

A place that's no stranger to tornadoes was hit again early Monday morning as storms dropped ten tornadoes in Alabama. The house on your left was hit by a tornado in Trussville, which is just northeast of Birmingham. These tornadoes caused over 100 injuries and at least two deaths as they moved through the darkness. Be sure to check out NWS Birmingham's updated public information page regarding this event to see the strengths and tracks that these tornadoes took. Arkansas was also hit badly by tornadoes (at least four as damage assessments continue) and you can read a synopsis of the severe weather event in that neck of the woods from this page posted by NWS Little Rock.

West Tennessee managed to escape the brunt of this system, but the National Weather Service in Memphis is investigating an area of damage near Lexington, TN (Henderson County) for a possible tornado. They've already confirmed straight-line wind damage in both Memphis and Middleburg, TN so far. NWS Memphis also has a page where you can see their ongoing assessment of damage in the area. UPDATE 12:10am: NWS Memphis has now confirmed an EF-1 tornado in Henderson County near Lexington, TN:

5 S Lexington [Henderson Co, TN] nws storm survey reports TORNADO of F1 at 22 Jan, 11:58 PM CST -- ef1 tornado with estimated winds of 105 mph touched down 5 miles south of lexington and continued east 8 miles. numerous trees were uprooted or snapped along the path. a roof was blown off a house. a shed in the backyard was also destroyed. the tornado touched down on primarily ridge tops before eventually lifting just northeast of butterscotch road. maximum width 150 yards.

This event again underscores the need for more ways to get the warning out to folks, especially during an overnight event when people are asleep. The best way to do this is have a NOAA Weather Radio in alert mode by your bedside or to have an app on your iPhone like iMapWeather Radio. There are text-based alerting solutions offered by individual TV stations and networks too.

1/18 - 3pm - Mississippi State Forecast, KY/IN Tornado Update

It's still cold out there in Mississippi after a frigid morning with temperatures in the 30's.  A cold front that passed through yesterday is to blame for the chill, but fear not, temperatures will be back to around 60 for highs by tomorrow afternoon. Quick turnaround, huh? Some rain and a few storms will be possible Friday night into Saturday with temperatures still increasing. A shot of severe weather may be possible sometime around the middle of next week, so keep watch for more updates on that forecast as it becomes clearer. Today's Mississippi State University forecast video is below:

Brownsboro Rd in Louisville

The count of yesterday's confirmed tornadoes in Kentucky and Indiana has now reached seven according to the National Weather Service in Louisville. The strongest of these was an EF-2 in Simpson and Allen Counties in Kentucky. Two of these tornadoes with winds of up to 100 mph occurred in highly-populated portions of the city of Louisville in Jefferson County. NWS Louisville is updating a webpage continuously with information about these tornadoes as it becomes available from their damage surveys.

1/17 - 5:15pm CST - A Day of Tornadoes in Kentuckiana and Mississippi

Two tornadoes have now been confirmed by NWS Louisville in Kentucky and Indiana. The first of these is an EF-1 that caused damage in the Springhurst area of Northeast Louisville (photos from John Belski's Weather Blog):

...EF-1 Tornado Confirmed in Jefferson County Kentucky...

Brownsboro Rd, Louisville

Damage Type: Tornado
Date: Jan 17 2012
EF Scale: 1
Wind Speed: 95 MPH
Path Length: 4.2 MILES
Path Width: 250 YARDS

Narrative: An NWS storm survey has confirmed an EF-1 tornado in Jefferson County, Kentucky.  The tornado touched down near the intersection of I-264 and Brownsboro Road.  The tornado tracked northeast to near the intersection of Hurstbourne and Brownsboro Road where it briefly lifted.  The tornado then reformed and crossed I-265.  The preliminary path length is 4.2 miles with a path width of 250 yards. This storm survey is ongoing and information in this statement will be updated as it becomes available.

The second tornado hit the airport in Madison, Indiana and carries an EF-0 rating with 85 mph winds:

...EF-0 Tornado Confirmed in Jefferson County Indiana...

Madison, IN Airport

Damage Type: Tornado
Date: Jan 17 2012
Start Time: 10:40 AM EST
End Time: 10:40 AM EST
EF Scale: 0
Wind Speed: 85 MPH
Path Length: 0.3 Miles
Path Width: 60 Yards

Narrative: An EF-0 tornado touched down at the Madison Municipal County Airport. Damage was confined to IMS Lane. The tornado touched down briefly along this path and moved an at least 500 pound dumpster 35 feet southeast. It also moved a Beechcraft/King Air plane 10 degrees and the nose gear was broken. The airport operations building had a disabled awning and post. Part of a hangar`s siding came off with siding and insulation up in trees. Several trees were snapped along the narrow path. A witness saw the swirl as the tornado touched down.

It's worth noting that the Storm Prediction Center did not issue a Tornado Watch today during this severe weather event. There may be more tornadoes confirmed in the Louisville area tomorrow as more surveys are conducted, especially in Clarksville, IN where damage has been well publicized. Two tornadoes were also reported in Mississippi this afternoon in Tippah and Marion Counties:

1800		3 NE DUMAS	TIPPAH	MS	3467	8880	TORNADO SIGHTED IN THE DUMAS PINE GROVE AREA NEAR HIGHWAY 4. (MEG)
2207		7 E SANDY HOOK	MARION	MS	3104	8969	PROBABLE TORNADO ... MOBILE HOME DESTROYED WITH PERSON POSSIBLY TRAPPED ... NUMEROUS TREES AND POWER LINES DOWN ... EMERGENCY PERSONNEL HAVING DIFFICULT TIME REACHING THE SIT (JAN)

Ratings on these possible tornadoes will likely come tomorrow when NWS crews are able to get out and survey the damage.

Unfortunately severe weather could become an issue again this time next week as a potent trough moves through the Southeastern portion of the nation. The GFS and Euro computer models indicate ample upper-level support and moisture return for a severe weather setup, but this is not set in stone yet as things can change in a week's time. Stay tuned!

1/14 - 10pm - All Sorts of Interesting Weather Today!

Henderson County, TN

The Wind Advisory that was in place for southwestern portions of Tennessee today was canceled at noon because wind speeds across the region were falling just below the 25 mph necessary. Nevertheless it was quite breezy and today's high in Jackson got up to 54 degrees, well above what was expected. Some clouds from the Alberta Clipper system (explained below) did make it into the region and I even managed to find some mammatus clouds, which are pictured on the right, in Henderson County, TN this morning. You usually find these underneath a springtime thunderstorm, but in this instance I think they may have been caused by snow hitting the layer of dry air in place underneath the clouds. Aside from the oddities of today's weather, the new week looks warm until Tuesday when showers and storms will give way to another cold snap and again another gradual warm up. Check out my forecast on WBBJ this morning (my first one in 2012!) below for more details:

What is an Alberta Clipper? Put simply it's a fast-moving area of low pressure that dives southward from the area near Alberta, Canada in the wintertime and spreads light snow to the Midwestern states. This particular Clipper was an interesting one because it centered its maximum snowfall in a very small area as the storm moved through Kentucky and Tennessee. More specifically, this area was just south of Louisville from Harrison County, Indiana to just south of Lexington, KY. Accumulations vary widely in Louisville because of the scattered nature of the snow bands that moved through, but they seem to range between a half inch to around two inches. South of town there are reports of more than three inches around Bardstown and Taylorsville! NWS Louisville's forecast graphic from earlier this evening points out pretty well where the most snow has fallen and you can tell exactly where the heavy snow band sat this afternoon. I drove through this band near Radcliff, KY on my way from Jackson, TN to Louisville and I can verify that it was indeed very heavy as indicated on the map. I took a quick video of today's snow at my house in Southeast Louisville just as I got home for my long weekend:

12/30 - 3:30pm - A Good Day to Fly a Kite in Kentucky

Gusty winds will continue through this afternoon in Louisville and most of Central Kentucky as a storm system in the Midwest creates quite the pressure gradient for strong winds. Winds at 5,000 feet (850 mb in weather geek speak) are high right now, surpassing 50 kts or 60 mph as you'll see in the orange shade on the left image. The peeks of sunshine we're seeing are allowing these winds to mix down to the surface due to heating, and that's why we're having the higher wind gusts.

The National Weather Service has issued a Wind Advisory for areas just south of Louisville since wind gusts have been hitting the criteria for this down that way. Even without the Wind Advisory, Louisville could see gusts surpassing 30 mph this afternoon as a cold front continues to approach from the west.

Check out some of the wind speeds and gusts from around the region as of 3pm. I've highlighted the wind gusts that are close to Wind Advisory criteria in orange and the ones that exceed the criteria (40 mph) in red:

Louisville Airport:   SW 17 mph, gusting to 24 mph

Bowman Field:         SW 18 mph, gusting to 29 mph

SE Louisville:          SW  9 mph,  gusting to 26 mph
Fort Knox:               SW 23 mph, gusting to 33 mph

Lexington:                SW 21 mph, gusting to 39 mph

Frankfort:                 SW 23 mph, gusting to 44 mph

Bowling Green:        SW 17 mph, gusting to 29 mph

More cities and observations are available hourly on the NWS's State Weather Roundup. A few light showers will be possible this evening in Louisville and surrounding areas as this front moves through.

12/3 - 2:45pm - Batten Down the Hatches, Heavy Rain is Coming!

West Tennessee and North Mississippi are going to be inundated with heavy rainfall starting tomorrow and lasting through Tuesday. The HPC's latest 12z rainfall forecast (right) has over 5 inches of precipitation in portions of Northwest Tennessee by the time this is all said and done, but amounts of 2 inches and over will be quite common across the area. Flooding will no doubt be a concern since this rain will fall on already saturated ground in a relatively short period of time (mostly Sunday and Monday), so the National Weather Service has issued a Flood Watch for the entirety of West Tennessee for Sunday morning through Monday night. The Tennessee and Mississippi Rivers will have to be watched during this, along with those low-lying areas that usually flood during these kinds of heavy rainfall events. After the rain and accompanying cold front move through, cooler temperatures and dry weather will be the rule for Wednesday and the remainder of the week. Check out my complete forecast on WBBJ this morning below for all the details:

11/30 - 4pm - Mid-South Winter Storm Wrap-Up

The National Weather Service in Memphis has released a snowfall map that recaps the measured snowfall totals across the Mid-South. Jackson, TN broke an all-time November snowfall record with 2.0", but note that slightly higher totals were recorded elsewhere in Madison County away from where the official observations are taken for the NWS. Look at those snowfall accumulations of over 5" in Northeast Arkansas and the Missouri Bootheel... very impressive! This was quite a rare storm and the method through which the storm produced the snow, a cut-off low that supplied its own cold air from aloft, is something that doesn't happen too often either.

The snow was even apparent on visible satellite this morning, which is amazing because temperatures were above freezing for most of yesterday:

Wintry weather should stay out of the forecast for at least the next week or so, but rain chances will be on the increase in West Tennessee early next week. The GFS computer model is hinting at the possibility of a little bit of snow late next weekend, but it's much too far out to make any predictions at this point. Certainly something to watch!

10/22 - 12:30pm - Warmer Temperatures in West TN, then Snow?

Jackson, TN bottomed out at 32 degrees this morning, which is two degrees warmer than our low temperature yesterday but still very chilly. We'll warm things up gradually around West Tennessee this weekend with 60's for highs today, 70's for both tomorrow and Monday, and 80's for Tuesday. What a warm-up! A cold front coming through on Wednesday night will generate some thunderstorms for Wednesday and Thursday, possibly into Friday as well. This system has slowed down on the computer models a little bit, but I think we should have all the rain out of here by Friday evening. It will be MUCH colder behind this front and as NWS Memphis points out, there's even a hint of some hypothetical snow on the computer models with this system:

IN FACT...LATEST MODEL GUIDANCE INDICATES AN UNSEASONABLY COLD UPPER LEVEL LOW MOVING
ALONG OR SOUTH OF THE INTERSTATE 40 CORRIDOR NEXT THURSDAY NIGHT INTO FRIDAY WITH 925 MB TEMPERATURES NEAR ZERO AND 1000-500MB THICKNESSES SUB 540 DAM. IF THIS WERE TO OCCUR...THEN IT WOULD BE POSSIBLE THAT SOME WET SNOW COULD MIX WITH THE RAIN IN SOME LOCATIONS THURSDAY NIGHT INTO EARLY FRIDAY MORNING. OBVIOUSLY THIS SYSTEM IS STILL SEVERAL DAYS AWAY AND THIS SCENARIO IS UNLIKELY CONSIDERING THAT WE ARE STILL IN LATE OCTOBER.

Honestly I don't think much if any snow will make it to the ground on Thursday night, but it could be close as some very cold air filters in behind that cold front. Check out some video from this morning's edition of Good Morning West Tennessee on WBBJ below:



I'll be on the 6pm and 10pm shows this evening (which will likely air a few minutes later than their assigned times due to football on TV), so be sure to tune in and check out the latest changes in your forecast!

8/25 - 4:15pm - Hurricane Irene's Fever Pitch

Hurricane Irene is certainly causing some drama both over the airwaves and along the East Coast where thousands are preparing for what could be that area's first hurricane strike in a while. This will also be the first hurricane to make landfall in the United States since Ike in 2008. States of emergency have been declared by the governors of North Carolina, Virginia, New Jersey, Maryland, and New York as the storm takes aim at the region. Areas from Wilmington, North Carolina to Cape Hatteras to Norfolk, Virginia will likely take the brunt of Irene as it makes landfall as a Category 2 or 3 storm on Saturday. A Hurricane Warning has been issued for the entire North Carolina coast and a Hurricane Watch is in effect from Virginia to New Jersey. On the satellite image to the top left you'll notice that Irene does not have a very apparent eye. This is because the storm has just completed an eyewall replacement cycle, which temporarily limits both the strength of the storm and the appearance of an eye. The eye will likely become much easier to see over the next 24 hours and the intensity of the storm will correspondingly increase.

The National Hurricane Center's 5pm EDT outlook for Hurricane Irene has the storm at Category 3 status with winds of 115 mph. For Tuesday and most of yesterday, it looked like Irene was going to miss much of the East Coast and curve back out to sea, but last night's and today's computer model runs have adjusted the storm's track quite a bit westward. This means hurricane force winds will be felt across a much larger portion of the North Carolina, Virginia coasts and even through to the Northeast and Delmarva Peninsula. To the right is a "spaghetti chart" showing all the computer model forecast tracks for Irene. There's a strong possibility that Irene may still be a Category 1 hurricane packing winds in excess of 75 mph and a storm surge up to 15 feet when it hits the New Jersey Shore, New York City, and Long Island areas on Sunday. While hurricanes that affect the Northeast aren't all that rare, the particular track of Irene and the intensity possible as it hits the area are causing great concern, especially about flooding. Folks from North Carolina to New England really need to pay attention to this storm this weekend and evacuate when instructed.

8/15 - 6pm - Severe Weather Craziness Back Home

Radar image from NWS Louisville

Saturday's severe weather in Louisville put many LG&E customers without power as winds exceeding 60 mph hit the city. At its peak the storm caused over 128,000 customers to lose power in Louisville, but that number has now dwindled down to 23,000. On radar it appears the storm may have bowed outward a bit due to the strong winds pushing ahead of it, and downbursts were likely the cause of much of the heavy damage in central parts of the city. Folks in Southeastern Jefferson County near the Jeffersontown, Middletown, Fisherville, and even down to Bullitt County saw a bit of a scary sight as the leading edge of the storm produced an arcus or shelf cloud. While not dangerous on its own this cloud often marks the leading edge of the gust front in a thunderstorm, which can carry damaging winds. Check out my photo from my back yard below:

With some schools still lacking power, Jefferson County Public Schools has cancelled classes tomorrow after already cancelling the first day of school for the academic year today. I'm not sure if JCPS has ever canceled the first day of school before, but this is certainly not the first time they've had to cancel due to power outages (wind storm of September '08 and major ice storm of January '09 are prime examples). A couple more nice weather days in Louisville will help with power restoration and tree clearing efforts.

Mississippi State Weather

I'm back at Mississippi State University for the semester and classes begin on Wednesday. The humidity been much lower in Starkville today since the passage of a cold front yesterday. Unfortunately reality will gradually return this week as temperatures surge back into the 90's and humidity increases as return flow transports Gulf moisture northward again. Daily small afternoon storm chances will return on Thursday or so.

Return to TV in Jackson, TN

If you're in Jackson, TN or the surrounding West Tennessee region, you'll want to tune into WBBJ ABC 7 this Saturday morning at 6am as I make my return to the Good Morning West Tennessee Saturday newscast. It's been about four months since my last show there due to my month-long storm chasing trip and time back home in Louisville, so I'm itching to get back to what I love doing most. We'll be bringing you weather updates every 10 minutes along with the morning's top news stories and events that you need to know about to get your weekend started!

8/7 - 5:15pm - More Storms in Our Future

Did the storms in Louisville wake you up this morning? I slept through them, which is probably a good thing because those that couldn't sleep through them early this morning sure looked tired today. Locations near Downtown Louisville saw rainfall amounts exceed one inch this morning, but most of the suburbs and outlying areas received under an inch. Click the image on the left from NWS Louisville to see a complete map of the rainfall totals from this morning. More storms are possible this afternoon and especially tomorrow as a cold front to our north provides a focus for development.

I've been watching the radar and satellite image for the past couple hours and it appears that ongoing storms dropping southeastward near Indianapolis may send out a some outflow boundaries toward Louisville over the next few hours. Outflow boundaries are like miniature cold fronts created by the cool air flowing out from a thunderstorm's downdraft. They also can cause storms to develop because they are a source of lift and that's why they're so important when forecasting short-term storm development. Since we have a little bit of wind shear and a very unstable atmosphere over the Louisville area right now, a kick from one of these southward-moving outflow boundaries may cause a few isolated storms to develop this evening. Storms may also form without the boundary if another small-scale feature or surface heating gets things going first. So, a vast majority of the area will stay dry, but if you happen to get under one of these wildcard isolated storms get ready for some heavy rain and wind.

There's a much better chance for storms tomorrow as a shortwave disturbance moves through the region. These storms will likely cluster together into an MCS (Mesoscale Convective System - complex of storms) and severe weather is possible. These scattered or MCS storms will roll through Louisville sometime tomorrow late afternoon or evening. Damaging winds, frequent lightning, and small hail will be the main threats from these storms. If they cluster together in a line, wind damage probabilities will be higher. The Storm Prediction Center has placed much of Kentucky, including Louisville, in a 30% Slight Risk area for severe weather tomorrow due to these factors.