During the early morning hours on February 7th, weak low pressure associated with an amplifying trough over the lower Missouri Valley developed across northern Alabama. During the day, this low moved northeast across southern Tennessee.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LMK wrote it up.
During the early morning hours on February 7th, weak low pressure associated with an amplifying trough over the lower Missouri Valley developed across northern Alabama. During the day, this low moved northeast across southern Tennessee. To the north of the track of this surface low, a narrow band of heavy wet snow developed along a thin track from southeast of Paducah through central Kentucky and into the Bluegrass Region. Even with temperatures hovering around 34 degrees, snow fell at such a fast rate that snow accumulated at a rate of an inch an hour. A few locations in central Kentucky received 4 to 5 inches.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Louisville, KY wrote its last area forecast discussion before the first event at Feb 7, 6:06 AM EST, 3 hours 54 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
606 AM EST MON FEB 7 2011
...UPDATED AVIATION DISCUSSION...
...FORECAST UPDATE...
WILL UPDATE TO INCLUDE SIMPSON...ALLEN AND BARREN COUNTIES IN THE
WINTER WEATHER ADVISORY. COLD AIR ALOFT...ALONG WITH SURFACE
TEMPERATURES IN THE MID 30S SHOULD ALLOW FOR UP TO 1 INCH OF SNOW
ACCUMULATION THROUGH MID AFTERNOON. UPDATED PRODUCTS HAVE ALREADY
BEEN SENT.
.SHORT TERM (TODAY AND TONIGHT)...
FORECAST CHALLENGE FOR TODAY CONTINUES TO BE WHEN AND WHERE WET SNOW
WILL FALL. CURRENT SURFACE OBS SHOW COLD FRONT JUST NORTHWEST OF THE
OHIO RIVER WITH A WELL DEFINED DEFORMATION AXIS IN THE LOWER LEVELS
ALONG THIS FRONT. RADAR SHOWS LIGHT PRECIPITATION STREAMING ALONG
THIS BOUNDARY...WITH THERMAL PROFILES STILL TOO WARM FOR ANYTHING
OTHER THAN RAIN AT THIS POINT. AT THE MID AND UPPER LEVELS...TROUGH
AXIS CURRENTLY OVER THE SOUTHERN PLAINS WILL SWING EASTWARD TO THE
GULF COAST STATES WITH ITS ASSOCIATED SURFACE LOW MOVING FROM THE
LOWER MISSISSIPPI RIVER VALLEY TO THE CENTRAL APPALACHIANS. EXPECT
PRECIPITATION COVERAGE TO GRADUALLY INCREASE ALONG AFOREMENTIONED
BOUNDARY BY DAWN...WITH WIDESPREAD COVERAGE BY EARLY AFTERNOON
ACROSS THE ENTIRE CWA.
THE CHALLENGE WITH PRECIPITATION TYPE WILL COME MAINLY WITH
UNCERTAINTY IN SURFACE AND BOUNDARY LAYER TEMPERATURES. FORECAST
SOUNDINGS CERTAINLY LOOK MARGINAL FOR SNOW...ESPECIALLY WITH SURFACE
TEMPERATURES EXPECTED TO REMAIN IN THE MID 30S FOR MUCH OF THE DAY.
NEVERTHELESS...ENOUGH COLD AIR LOOKS TO MOVE IN ALOFT FOR A
SITUATION WHERE SNOW WILL BE FALLING WITH SURFACE TEMPS IN THE MID
30S. CURRENT LAPS 925 MB ANALYSIS SHOWS FREEZING LINE JUST SOUTHEAST
OF THE OHIO RIVER WHICH INDICATES TEMPERATURES JUST ABOVE THE
SURFACE WOULD SUPPORT SNOW. HOWEVER...SURFACE TEMPERATURES ARE
CURRENTLY IN THE MID TO UPPER 30S. EXPECT THAT TEMPS WILL ONLY
GRADUALLY FALL TO THE MID 30S THROUGH THE AFTERNOON ACROSS MUCH OF
THE CWA...WHICH WILL MAKE FOR WHERE THE RAIN/SNOW LINE SETS UP VERY
TRICKY.
...TIMING OF CHANGE OVER...
TIMING OF CHANGE OVER IN SOUTHERN INDIANA STILL LOOKS GOOD WITH
MOSTLY SNOW AROUND DAYBREAK. JUST SOUTHEAST OF THE OHIO RIVER CAN
EXPECT MOSTLY RAIN WITH SOME SNOWFLAKES MIXING IN. AS WE PROGRESS
THROUGH MID TO LATE MORNING...ANTICIPATE THE RAIN/SNOW LINE TO BE
JUST SOUTHEAST OF THE OHIO RIVER WITH A RAIN/SNOW MIX POSSIBLE FROM
BOWLING GREEN TO LEXINGTON. BY EARLY AFTERNOON...RAIN SNOW LINE
COULD WORK ITS WAY BACK NORTH TO THE OHIO RIVER...BASED ON SURFACE
TEMPERATURES ALONE AS LOWER AND MIDLEVEL WILL CONTINUE TO GET
COLDER.
MID AFTERNOON WILL BE WHEN COOLER AIR AT THE SURFACE QUICKLY SURGES
SOUTHEAST AND PRECIPITATION CHANGES TO ALL SNOW RAPIDLY TO THE
SOUTHEAST ACROSS THE ENTIRE CWA. HEAVIEST PRECIPITATION SHOULD END
ACROSS SOUTHERN INDIANA AND NORTHERN KENTUCKY BY LATE AFTERNOON...
WITH PRECIPITATION ENDING EAST OF I 65 BY AROUND 10 PM EST.
...ACCUMULATIONS...
STILL AGREE WITH THE PREVIOUS FORECAST ON ACCUMULATIONS WITH AROUND
1 TO 2 INCHES IN THE ADVISORY AREA...AND LESSER AMOUNTS UP TO 1 INCH
IN THE FAR EASTERN CWA. UP TO 4 TENTHS OF LIQUID QPF MAY FALL WITH
THIS SYSTEM...HOWEVER THE TIME OF DAY AND SURFACE TEMPERATURES
SHOULD LIMIT ACCUMULATIONS SIGNIFICANTLY. OVERALL...STILL DO NOT
EXPECT THIS SYSTEM TO HAVE MUCH OF AN IMPACT ON ROADWAYS EVEN THOUGH
MODERATE SNOW WILL FALL AT TIMES. GRASSY AND ELEVATED SURFACES WILL
BE MOST LIKELY TO ACCUMULATE SNOW. SOUTHERN INDIANA WILL HAVE THE
OVERALL COOLEST TEMPERATURE PROFILE...ALTHOUGH QPF WILL BE MORE
LIMITED THE FURTHER NORTH YOU GO...THEREFORE EXPECT ONLY AN INCH OR
TWO TOTAL FOR THE EVENT. EXPECT THE MOST SNOWFALL TO ACCUMULATE FROM
RUSSELLVILLE TO ELIZABETHTOWN TO SHELBYVILLE...NORTHWARD TO THE OHIO
RIVER. IN THIS AREA A SOLID 2 INCHES IS POSSIBLE.
...ADVISORY...
WILL CHANGE THE ADVISORY JUST A BIT...ADDING A TIER OF COUNTIES FROM
MADISON TO CASEY IN OUR FAR EAST. CHANGE OVER WILL HAPPEN LATE IN
THIS AREA WITH ONLY UP TO 1 INCH ACCUMULATION EXPECTED...ALTHOUGH
COLD AIR RAPIDLY MOVING IN CAUSES CONCERN FOR WET ROADS QUICKLY
TRANSITIONING TO A SLUSHY/ICY MIX. OVERALL TREND IS SLOWER WITH
PRECIPITATION AND WILL BREAK THE BLUEGRASS REGION INTO A THIRD
ADVISORY SECTION ENDING AT 10 PM EST. THE OTHER SECTIONS WILL GO
UNTIL 4 PM EST FOLLOWING THE PREVIOUS FORECAST.
...CONCERNS...
OVERALL...FEEL PRETTY GOOD ABOUT THE NORTHERN TWO THIRDS OF THE
ADVISORY AREA...HOWEVER AM SKEPTICAL ABOUT THE SOUTHERN THIRD FROM
BOWLING GREEN TO LEXINGTON. AM NOT CONFIDENT THAT THE RAIN SNOW LINE
WILL MAKE IT FAR ENOUGH EAST IN TIME BEFORE THE BULK OF THE DEEP
MOISTURE MOVES OUT. WILL LEAVE THE ADVISORY AS IS SINCE CHANGE OVER
IS STILL EXPECTED TO OCCUR AND A QUICK HALF AN INCH TO AN INCH COULD
FALL BY MID TO LATE AFTERNOON.
.LONG TERM (TUESDAY - SUNDAY)...
TUESDAY THROUGH THURSDAY...
LATEST MODEL CONSENSUS CONTINUES TO SHOW STRONG AREA OF HIGH
PRESSURE BUILDING INTO THE GREAT PLANS AND EXPANDING EASTWARD INTO
THE OHIO VALLEY AT THE BEGINNING OF THE PERIOD. THUS...WE WILL
CONTINUE TO FORECAST DRY BUT COOL CONDITIONS FOR TUESDAY AND TUESDAY
NIGHT. HIGHS TUESDAY WILL LIKELY RANGE FROM THE MID 20S ACROSS
SOUTHERN INDIANA AND NORTHERN KENTUCKY TO THE UPPER 20S ALONG THE
KY/TN BORDER. OVERNIGHT LOWS TUESDAY NIGHT ARE EXPECTED TO DROP
INTO THE MID-UPPER TEENS. IT IS FORESEEABLE THAT THESE TEMPS MAY BE
A LITTLE ON THE HIGH SIDE SHOULD WE GET SNOWCOVER FROM THE SYSTEM ON
MONDAY.
BY WEDNESDAY...FAIRLY ACTIVE WEATHER PATTERN SHOULD BE IN PROGRESS
ACROSS MUCH OF NORTH AMERICA AS BOTH THE NORTHERN AND SOUTHERN
STREAM OF THE UPPER JET GET ACTIVE. MAJORITY OF THE MEDIUM TO LONG
RANGE MODELS CONTINUE TO SHOW A RATHER LARGE RIBBON OF MOISTURE
COMING OUT OF THE PACIFIC AND THEN POOLING IN A LARGE 500MB TROUGH
OVER THE SOUTHERN PLAINS. POOLING OF THE MOISTURE SEEMS TO BE
RELATED TO THE STRONG RIDGE OF HIGH PRESSURE DROPPING OUT OF THE
NORTHERN PLAINS...COMBINED WITH THE VERY STRONG FLOW OF THE NORTHERN
JET BRANCH.
BY LATE WED INTO THURSDAY...A WAVE WILL ATTEMPT TO DEVELOP IN THE
SOUTHERN STREAM. THIS MAY RESULT IN CYCLOGENESIS ALONG THE TEXAS
GULF COAST. HOWEVER...THE STRONG NORTHERN STREAM OF THE JET MAY
RESULT IN THIS WAVE BEING MORE OPEN AND WEAK. SHOULD THIS BE THE
CASE...THE SFC LOW MAY BE MORE OF AN INVERTED TROUGH MOVING ALONG
THE GULF COAST BEFORE CLOSING OFF AS IT MAKES IT TO THE SOUTHEAST
U.S. COAST BY LATE THURSDAY. BOTH THE GFS AND EURO MODELS CONTINUE
TO SHOW THE OVERPOWERING NORTHERN STREAM KEEPING THIS SYSTEM FURTHER
SOUTH WITH EACH MODEL RUN. ON THE OTHER HAND...THE NAM-WRF RUNS ARE
A BIT MORE NORTH AND DO NOT CONTAIN NEARLY AS STRONG ENERGETIC
NORTHERLY BRANCH AS THE GFS/EURO SOLUTIONS DO. GIVEN THAT WE'RE IN
THE LATTER PORTION OF THE NAM-WRF MODEL RUN...WILL TREND THINGS
CLOSER TO A GFS/EURO BLEND...WHICH WILL RESULT IN DECREASING CHANCES
OF PRECIP ACROSS THE NORTH...WHILE MAINTAINING BEST CHANCES ACROSS
SOUTHERN KY.
SENSIBLE WEATHER THROUGH THE PERIOD WILL BE CHARACTERIZED BY A LARGE
INCREASE IN MID-HIGH CLOUDS DURING THE DAY ON WEDNESDAY. WEAK
ISENTROPIC LIFT AIDED BY WIDESPREAD LIFT ASSOCIATED BY HEIGHT FALLS
OVERSPREADING THE REGION SHOULD RESULT IN LIGHT SNOWS DEVELOPING
ACROSS THE REGION WEDNESDAY AFTERNOON/EVE. AS DEEPER MOISTURE
TRANSPORT AND LIFT INCREASE...WE SHOULD SEE THE MOST WIDESPREAD
PRECIPITATION WEDNESDAY NIGHT INTO EARLY THURSDAY. IN
GENERAL...GIVEN THE FURTHER SOUTH TREND IN THE MODELS...THE
BEST/HIGHEST QPF AMOUNTS STILL LOOK TO BE ACROSS THE SOUTHERN THIRD
OF KENTUCKY. SNOWFALL ACCUMULATIONS ARE STILL TOUGH TO PIN DOWN BUT
SOME LIGHT ACCUMULATIONS STILL LOOK TO BE IN THE CARDS ACROSS
SOUTHERN INDIANA AND NORTHERN KENTUCKY...BUT SEVERAL INCHES OF
ACCUMULATION WILL BE POSSIBLE IN THE SOUTHERN PART OF THE STATE.
SFC WAVE IS FORECAST TO QUICKLY MOVE EAST...THUS PRECIPITATION
SHOULD QUICKLY EXIT OUR AREA BY DAWN THURSDAY MORNING. MAY KEEP A
CHANCE OF FLURRIES IN THE SOUTHEAST EARLY ON THURSDAY...BUT BY AND
LARGE IT SHOULD BE A DRY AND COLD DAY.
AS FOR TEMPERATURES...GENERALLY STUCK WITH MID-UPPER 20S ACROSS THE
REGION FOR WEDNESDAY WITH SOME LOWER 30S ACROSS THE SOUTH. LOWS WED
NIGHT WILL DROP INTO THE LOWER-MID TEENS WITH HIGHS ON THURSDAY
WARMING BACK UP INTO THE MID-UPPER 20S.
THURSDAY NIGHT THROUGH SUNDAY...
NO MAJOR CHANGES WERE MADE IN THIS PORTION OF THE FORECAST PERIOD.
PREVIOUS METEOROLOGICAL DISCUSSION FOLLOWS...
DRY CONDITIONS ARE STILL ON TAP FOR THURSDAY NIGHT INTO THE WEEKEND
AS THE PLAINS HIGH PRESSURE SLOWLY OOZES ACROSS THE SOUTHEASTERN
UNITED STATES. THE COLDEST AIR LOOKS TO MOVE THROUGH OUR REGION
THURSDAY NIGHT AND FRIDAY WITH THE LOWEST 500HPA HEIGHTS...FRESH
SNOWCOVER...CLEARING SKIES...AND SURFACE FLOW FROM THE NORTHWEST OFF
THE DEEP MIDWEST SNOWFIELD.
HOWEVER IT ALSO LOOKS TO BE A QUICK SHOT OF COLD. THE UPPER TROF
WILL MOVE OFF TO THE EAST QUICKLY AND AT THE SURFACE SOUTHWESTERLY
FLOW GETS UNDERWAY BY FRIDAY MORNING AND CONTINUES THROUGH THE
WEEKEND. MODERATION OF TEMPERATURES OVER THE WEEKEND STILL SEEMS
REASONABLE AND IS IN AGREEMENT WITH GUIDANCE AND HPC TRENDS. WILL
TEMPER THE WARM-UP SOME DUE TO THE PRESENCE OF THE NEW SNOW...BUT
WILL STILL GO AHEAD AND ALLOW TEMPERATURES TO RISE OVER THE WEEKEND.
&&
.AVIATION (12Z TAF ISSUANCE)...
COLD FRONTAL BOUNDARY IS CURRENTLY OVER SDF TO BWG LINE AND WILL
CONTINUE TO PROGRESS SOUTHEAST THROUGH THE DAY TODAY. RAIN SHOWERS
WILL GRADUALLY TRANSITION TO SNOW THROUGHOUT THE DAY WITH SDF SEEING
SNOW AS EARLY AS 9 AM EST. BWG AND LEX SHOULD SEE A CHANGEOVER BY
EARLY AFTERNOON. EXPECT SOLID MVFR CIGS OUTSIDE ANY RAIN OR SNOW
SHOWER...WITH IFR OR WORSE IN THE SNOW. VISIBILITIES COULD DROP DOWN
INTO THE LIFR OR WORSE CATEGORIES THIS AFTERNOON DURING ANY MODERATE
SNOWFALL. OTHERWISE...WINDS WILL MAINLY BE OUT OF THE NORTH
NORTHWEST TODAY INCREASING TO AROUND 10 MPH BY THIS AFTERNOON.
EXPECT SNOW TO TAPER OFF AT SDF AND BWG BY LATE AFTERNOON WITH SNOW
ENDING AT LEX AROUND MIDNIGHT. SOLID MVFR CIGS ALONG WITH SCATTERED
FLURRIES SHOULD PERSIST THROUGH THE END OF THE FORECAST PERIOD.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR KYZ023-032.
WINTER WEATHER ADVISORY FROM 4 PM EST /3 PM CST/ THIS AFTERNOON
TO 10 PM EST /9 PM CST/ THIS EVENING FOR KYZ035>037-039>043-
046>049-054>057-064>067.
WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR KYZ024>031-033-034-038-045-053-061>063-070>074.
IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR INZ076>079-083-084-089>092.
&&
UPDATE.........BJS
SHORT TERM.....BJS
LONG TERM......MJ
AVIATION.......BJSHAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE LOUISVILLE KY 545 AM EST MON FEB 7 2011 INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067- 070>074-081045- ORANGE IN-WASHINGTON IN-SCOTT IN-JEFFERSON IN-DUBOIS IN- CRAWFORD IN-PERRY IN-HARRISON IN-FLOYD IN-CLARK IN-HANCOCK KY- BRECKINRIDGE KY-MEADE KY-OHIO KY-GRAYSON KY-HARDIN KY-BULLITT KY- JEFFERSON KY-OLDHAM KY-TRIMBLE KY-HENRY KY-SHELBY KY-FRANKLIN KY- SCOTT KY-HARRISON KY-SPENCER KY-ANDERSON KY-WOODFORD KY- FAYETTE KY-BOURBON KY-NICHOLAS KY-NELSON KY-WASHINGTON KY- MERCER KY-JESSAMINE KY-CLARK KY-LARUE KY-MARION KY-BOYLE KY- GARRARD KY-MADISON KY-BUTLER KY-EDMONSON KY-HART KY-GREEN KY- TAYLOR KY-CASEY KY-LINCOLN KY-LOGAN KY-WARREN KY-SIMPSON KY- ALLEN KY-BARREN KY- 545 AM EST MON FEB 7 2011 /445 AM CST MON FEB 7 2011/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL INDIANA AND CENTRAL KENTUCKY. .DAY ONE...TODAY AND TONIGHT. RAIN WILL CHANGE TO SNOW ACROSS THE REGION TODAY WITH SNOW ACCUMULATIONS OF 1 TO 2 INCHES FOR MOST AREAS. THIS MAY RESULT IN SLUSHY ACCUMULATIONS OF SNOW ON ROADS WITH TEMPERATURES AT OR JUST ABOVE THE FREEZING MARK. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. AN ELONGATED AREA OF LOW PRESSURE OVER THE SOUTHEAST UNITED STATES WILL JOIN FORCES WITH A POOL OF MOISTURE COMING IN FROM THE WEST TO PRODUCE SNOWFALL OVER THE REGION WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. MOST OF THE SNOW WILL FALL WEDNESDAY NIGHT OVER SOUTHERN KENTUCKY...WITH 1 TO 3 INCHES OF ACCUMULATION PROBABLE WITHIN A FEW COUNTIES OF THE TENNESSEE BORDER. .SPOTTER INFORMATION STATEMENT... PLEASE REPORT PRECIPITATION TYPE AND ANY SNOWFALL ACCUMULATION TO THE NATIONAL WEATHER SERVICE. KYZ075>078-081-082-081045- MONROE KY-METCALFE KY-ADAIR KY-RUSSELL KY-CUMBERLAND KY- CLINTON KY- 445 AM CST MON FEB 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL KENTUCKY. .DAY ONE...TODAY AND TONIGHT. SNOW MAY MIX WITH RAIN AT TIMES THIS AFTERNOON AND EVENING. ROADWAYS COULD BRIEFLY BECOME SLUSHY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. AN ELONGATED AREA OF LOW PRESSURE OVER THE SOUTHEAST UNITED STATES WILL JOIN FORCES WITH A POOL OF MOISTURE COMING IN FROM THE WEST TO PRODUCE SNOWFALL OVER THE REGION WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. MOST OF THE SNOW WILL FALL WEDNESDAY NIGHT OVER SOUTHERN KENTUCKY...WITH 1 TO 3 INCHES OF ACCUMULATION PROBABLE WITHIN A FEW COUNTIES OF THE TENNESSEE BORDER. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME. BJS/MJ
The national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
Five inches of snow fell near Boston, in western Nelson County.
Four and one half inches of snow fell in Clarkson.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kentucky in 2011Every state in 2011This day in weather historyWarnings in Kentucky, February 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 271102, 271101.