A three week dry period to begin the month led to parts of north central Wisconsin slipping back into severe drought conditions (D2).
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 ARX wrote it up.
A three week dry period to begin the month led to parts of north central Wisconsin slipping back into severe drought conditions (D2).
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 La Crosse, WI wrote its last area forecast discussion before the first event at Sep 19, 1:38 AM CST, 4 hours 22 minutes earlier.
AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE LA CROSSE WI 238 AM CDT SAT SEP 19 2009 .SHORT TERM...TODAY THROUGH MONDAY MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES SUNDAY NIGHT INTO MONDAY. LATEST 11-3.9U FOG SATELLITE IMAGERY INDICATING STRATOCUMULUS DECK CLOUDS OVER SOUTH CENTRAL WISCONSIN EXPANDING WESTWARD AND HIGH THIN CIRRUS STREAMING NORTHWARD FROM WEAKENING UPPER LEVEL LOW OVER THE SOUTHERN PLAINS. LATEST RUC BUFKIT SOUNDING OVER SOUTHWEST WISCONSIN DEPICTING THIS STRATOCUMULUS DECK AT TOP OF INVERSION AROUND 850MB. THE 19.00Z GFS AND NAM INITIALIZED OVERALL UPPER LEVEL PATTERN WELL PER LATEST WATER VAPOR SATELLITE IMAGERY. BOTH THE MODELS INITIALIZED THE STRATOCUMULUS DECK OVER SOUTH CENTRAL WISCONSIN WELL PER 850MB MOISTURE FIELD. MAIN DIFFERENCES BETWEEN THE DETERMINISTIC MODELS IS GFS SLIGHTLY STRONGER WITH DIGGING SHORTWAVE TROUGH OVER THE ROCKY MOUNTAINS SUNDAY NIGHT INTO MONDAY...AND GFS IS SLIGHTLY FASTER WITH FIRST PIECE OF ENERGY EJECTING OUT AHEAD OF SURFACE FRONT/UPPER LEVEL TROUGH AT 12Z AND 18Z MONDAY. THOUGH... MODELS ARE IN MUCH BETTER AGREEMENT IN PLACEMENT AND MOVEMENT OF UPPER LEVEL LOW OVER THE SOUTHERN PLAINS STATES INTO THE GREAT LAKES REGION SUNDAY NIGHT INTO MONDAY. TODAY INTO SUNDAY...SURFACE RIDGE OVER EASTERN MICHIGAN REMAINS IN CONTROL OF THE REGION. WITH DECENT SUBSIDENCE OVER THE AREA TODAY AND FULL SUN ACROSS FORECAST AREA. THIS SHOULD ALLOW STRATOCUMULUS DECK TO DECREASE AND BECOME A CU FIELD BY 18Z TODAY. DUE TO DRIER AIR ALOFT MIXING DOWN CUMULUS FIELD SHOULD THIN OUT LATE THIS AFTERNOON AND ALLOW FOR MOSTLY CLEAR SKIES TONIGHT. THIS IS IN AGREEMENT WITH THE 19.00Z NAM BUFKIT SOUNDINGS ACROSS FORECAST AREA. WITH RIDGE ENTRENCHED OVER FORECAST AREA AND MODELS IN BETTER AGREEMENT IN MOVING UPPER LEVEL LOW OVER THE SOUTHERN PLAINS INTO EASTERN ILLINOIS AND INDIANA...AND BETTER FORCING SOUTH AND EAST OF FORECAST AREA. FORECAST AREA WILL REMAIN DRY DURING THE DAY SUNDAY. SHORTWAVE TROUGH EMBEDDED IN NORTHERN STREAM AND ASSOCIATED COLD FRONT APPROACHES FORECAST AREA SUNDAY NIGHT INTO MONDAY. BOTH THE 19.00Z GFS AND NAM ARE IN AGREEMENT INCREASING THE FORCING AND MOISTURE INTO FORECAST AREA MONDAY...THOUGH GFS IS SLIGHTLY FASTER IN MOVING FIRST PIECE OF ENERGY OUT AHEAD OF COLD FRONT/SHORTWAVE TROUGH THAN THE NAM. CONFIDENCE IN TIMING OF PRECIPITATION INTO FORECAST AREA IS MODERATE. BOTH THE 19.00Z DETERMINISTIC RUNS OF THE GFS AND NAM ARE INDICATING DECENT MOISTURE TRANSPORT AND CONVERGENCE ASSOCIATED WITH SHORTWAVE TROUGH MONDAY. THOUGH...MODELS ARE INDICATING A DELAY IN MOVEMENT OF FORCING AND MOISTURE INTO FORECAST AREA...HAVE ADJUSTED THE ONSET OF PRECIPITATION INTO FORECAST AREA MONDAY. BOTH MODELS CONTINUE TO INDICATE SURFACE BASED CAPE OF 500 TO 900 J/KG ALONG AND AHEAD OF SURFACE COLD FRONT/SHORTWAVE TROUGH MONDAY. WILL CONTINUE MENTION OF ISOLATED THUNDER FOR MONDAY. .LONG TERM...MONDAY NIGHT THROUGH FRIDAY MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES THROUGH THE FORECAST PERIOD. THE 19.00Z GFS AND ECMWF CONTINUE TO DIFFER ON PLACEMENT AND TIMING OF CUT-OFF UPPER LEVEL LOW OVER THE PLAINS AND ROCKY MOUNTAIN STATES WEDNESDAY INTO LATE NEXT WEEK. THEREFORE... CONFIDENCE IN PRECIPITATION CHANCES FROM WEDNESDAY INTO THE REST OF THE FORECAST PERIOD REMAINS LOW. BOTH MODELS ARE INDICATING BEST FORCING AND MOISTURE CONVERGENCE WITH SURFACE COLD FRONT/UPPER LEVEL SHORTWAVE TROUGH OVER FORECAST AREA MONDAY NIGHT INTO TUESDAY. HAVE INCREASED PRECIPITATION CHANCES SLIGHTLY ACROSS FORECAST AREA MONDAY NIGHT. THEN...THE 19.00Z GFS AND ECMWF DIFFER ON PLACEMENT AND TIMING OF PHASING CUT-OFF LOW INTO THE NORTHERN STREAM LATE NEXT WEEK. BOTH THE MODELS ARE INDICATING SHORTWAVE ENERGY EMBEDDED IN NORTHERN STREAM TO LIFT AND PHASE UPPER LEVEL CUT- OFF LOW INTO THE NORTHERN STREAM LATE IN THE PERIOD...WITH THE GFS MUCH FARTHER WEST PLACEMENT AND SLOWER IN MOVEMENT THAN THE ECMWF. AT THIS TIME...WILL MAKE NO CHANGES...AS TIMING OF PRECIPITATION CHANCES WEDNESDAY INTO LATE NEXT WEEK IS DIFFICULT TO PIN DOWN. && .AVIATION...TODAY THROUGH TONIGHT SOME HIGH CLOUDS HAVE MOVED ACROSS THE REGION EARLY THIS MORNING...ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE SITTING OVER THE SOUTHERN PLAINS. GOOD LOW LEVEL LAPSE RATES AND SOME SATURATION IN THE 700-850 MB LAYER...PER TIME/HEIGHT X-SECTIONS...SHOULD RESULT IN SOME AFTERNOON CU DEVELOPMENT. SPC/NSSL WRF HINT AT SOME SPOTTY -SHRA FOR THE AFTERNOON/EVE...BUT NO WEAK FRONTAL BOUNDARY TO FOCUS ON LIKE YESTERDAY...SO WILL STAY DRY FOR NOW. FOG CONCERNS CONTINUE FOR THE RIVER VALLEYS...AS CONDITIONS ARE GENERALLY TOO DRY ELSEWHERE. BUFKIT SOUNDINGS SHOW THE VERTICAL WIND PROFILES FAIRLY STIRRED OFF THE SFC...WITH 10 KTS OR MORE OF WIND BY 400 FT OR SO. AGAIN...THIS SHOULD PREVENT A WIDESPREAD VALLEY FOG. BCFG MIGHT BE MOST APPROPRIATE FOR KLSE THIS MORNING/SUN MORNING. WILL MONITOR CONDITIONS FOR 12Z ISSUANCE. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && SHORT/LONG TERM...DTJ AVIATION..........RIECK
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 500 AM CDT SAT SEP 19 2009 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-032>034- 041>044-053>055-061-201000- ADAMS-ALLAMAKEE-BUFFALO-CHICKASAW-CLARK-CLAYTON-CRAWFORD-DODGE- FAYETTE-FILLMORE-FLOYD-GRANT-HOUSTON-HOWARD-JACKSON-JUNEAU-LA CROSSE- MITCHELL-MONROE-MOWER-OLMSTED-RICHLAND-TAYLOR-TREMPEALEAU-VERNON- WABASHA-WINNESHIEK-WINONA- 500 AM CDT SAT SEP 19 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST INTO CENTRAL WISCONSIN. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY AN UPPER AIR DISTURBANCE AND A NORTH TO SOUTH RUNNING SURFACE FRONT WILL BRING THE THREAT FOR THUNDERSTORMS TO THE REGION ON MONDAY. INSTABILITY WILL BE WEAK...AND SEVERE WEATHER IS NOT ANTICIPATED. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. .EMERGENCY MANAGEMENT COORDINATION... NO CALL IS SCHEDULED. RIECK
The national radar mosaic for the moment the first event began.
2 drought. Local standard time, as filed.
Drought levels reached severe (D2) in mid-September and continued into October.
Drought levels reached severe (D2) in mid-September and continued into October.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2009Every state in 2009This day in weather historyWarnings in Wisconsin, September 2009
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: 192624, 192625.