Dense fog reduced the visibility to a half mile or less during the early morning hours of August 5th across southeast Minnesota. A car rolled off a Rochester (Olmsted County) road in the fog, injuring one of the occupants of the vehicle.
Every event with a place to put it; 1 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.
Dense fog reduced the visibility to a half mile or less during the early morning hours of August 5th across southeast Minnesota. A car rolled off a Rochester (Olmsted County) road in the fog, injuring one of the occupants of the vehicle.
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 Aug 4, 9:32 PM CST, 28 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 1032 PM CDT MON AUG 4 2014 .UPDATE... ISSUED AT 624 PM CDT MON AUG 4 2014 EXPANDED SPATIALLY AND INCREASED THE COVERAGE OF FOG LATER TONIGHT. UNDERNEATH THE ASSUMPTION CLOUDS CLEAR OR AT LEAST SCATTER OUT...WHICH SEEMS REASONABLE GIVEN WATER VAPOR AND VISIBLE SATELLITE IMAGERY...THE SETUP IS VERY FAVORABLE FOR AREAL FOG TO FORM. SREF AND HIRES ARW/NMM VISIBILITY PROGS ALL POINT TO LOCATIONS ALONG AND SOUTH OF I-90 AS THE MOST FAVORABLE AREA...WHICH MAKES SENSE GIVEN SOME DEWPOINT DRYING THAT COULD MAKE ITS WAY INTO NORTH CENTRAL WISCONSIN LATE TONIGHT. IT\S POSSIBLE DENSE FOG ADVISORIES WILL BE NEEDED TOMORROW MORNING...ESPECIALLY IF CLOUDS CLEAR OUT. PRECIPITATION IS GENERALLY DIMINISHING ON SCHEDULE...AS COOLING TEMPERATURES FROM RECENT RAIN AND OUTFLOWS HELP ELIMINATE INSTABILITY. WOULD NOT BE SURPRISED IF BY 03Z ALL THE PRECIPITATION HAS ENDED...WHICH WOULD REQUIRE DIMINISHING PRECIPITATION CHANCES QUICKER. && .SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT) ISSUED AT 316 PM MON AUG 4 2014 MAIN CONCERNS THIS PERIOD...SHRA/TSRA THIS EVENING...VALLEY FOG POTENTIAL LATE TONIGHT...SHRA/TSRA CHANCES ACROSS THE SOUTHWEST SIDE OF THE FCST AREA TUE NIGHT. DATA ANALYSIS AT 18Z HAD A WEAK SFC TROUGH/FRONT FROM EAST CENTRAL WI THRU THE FCST AREA NEAR KLSE THEN SOUTHWEST TO NEAR KOMA. SFC OBS/LAPS ANALYSIS AGAIN INDICATED SB/ML CAPE OF 1K-2K J/KG DEVELOP ACROSS THE FCST AREA BY 17-18Z...WITH NO CAPPING. WV IMAGERY SHOWED YET ANOTHER WEAK SHORTWAVE APPROACHING FROM THE NORTHWEST. COMBINATION OF THE 3 ALLOWED FOR RATHER RAPID DEVELOPMENT OF SHRA/ TSRA ACROSS THE CENTRAL/NORTH PARTS OF THE FCST AREA BETWEEN 17-18Z. SOME OF THE TSRA PRODUCING WIND GUSTS TO 40MPH NEAR ZERO VSBY IN THE DOWNPOURS AND 1 TO 2 INCHES OF RAIN IN AN HOUR. TEMPS IN THE TSRA DROP TO AROUND 70F. NO SIGNIFICANT ISSUES NOTED WITH 04.12Z MODEL INITIALIZATIONS. GFS WITH ITS USUAL STRUGGLE ON SFC DEW POINTS /+5F TO -5F ERROR/ ACROSS THE UPPER MIDWEST. MODELS OFFERING A TIGHTER CONSENSUS TONIGHT/TUE AS NORTHWEST FLOW ALOFT REMAINS OVER THE REGION AND WEAK SHORTWAVES CONTINUE TO RIPPLE SOUTHEAST THRU IT. BETTER CONSENSUS WITH THE STRONGER SHORTWAVE TROUGH INTO THE NORTHERN PLAINS TUE NIGHT. COMPARED TO 03.12Z RUNS...TREND FAVORS WEAKER/LESS AGGRESSIVE WITH THIS TROUGH. WITH THE TIGHTER CONSENSUS AND SOME CONSISTENCY ON THE SHORTWAVE DETAILS...SHORT TERM FCST CONFIDENCE IS GOOD THIS CYCLE. IN THE SHORT TERM...THE LOWER LEVEL TROUGH/FRONT WILL CONTINUE TO SAG THRU THE AREA LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS AS WEAK SHORTWAVE ENERGY RIPPLES SOUTHEAST THRU THE FLOW. NUMEROUS SHRA/TSRA WILL PERSIST ACROSS THE CENTRAL/SOUTH PARTS OF THE FCST AREA THRU 00-01Z. WITH PW VALUES AROUND 1.5 INCHES AND ML/SB CAPES IN THE THE 1K TO 2K+ J/KG RANGE...STRONGER TSRA THRU EARLY EVENING WILL BE CAPABLE OF HAIL...GUSTY WINDS AND LOCALIZED HEAVY RAINS. SHRA/TSRA WILL GRADUALLY DIMINISH/END AFTER 01Z AS THE FRONT PUSHES SOUTH OF THE AREA...INSTABILITY WANES WITH SUNSET AND DRYING HIGH PRESSURE BUILDS INTO THE AREA. RAINS FROM THIS AFTERNOON/EVENING WILL MOISTEN THE GROUND/BOUNDARY LAYER FOR TONIGHT...WITH LATE NIGHT/EARLY MORNING VALLEY FOG LOOKING LIKELY TONIGHT. DECREASE OF CLOUDS LATER TONIGHT/WEAK GRADIENT WILL ALLOW BOUNDARY LAYER TO DECOUPLE AND STRONGER RADIATIONAL COOLING. ONCE AGAIN ADDED PATCHY TO AREAS OF FOG TO THE RIVER VALLEYS AND LOW LAYING LOCATIONS ACROSS THE NORTHEAST PORTION OF THE FCST AREA IN THE 08-13Z TIME-FRAME. QUIET/DRY TUE/TUE EVENING WITH LACK OF FORCING SIGNALS AND MODEL SOUNDING SHOWING LIMITED CAPE CAPPED BY AN INVERSION BELOW 700MB. SHORTWAVE ENERGY LIFTING OUT OF THE CENTRAL ROCKIES STRENGTHENS SFC- 850MB LOW PRESSURE IN THE CENTRAL PLAINS TUE NIGHT. FRONTAL BOUNDARY FROM TODAY BEGINS TO RETURN NORTH AS A WARM FRONT AHEAD OF THIS LOW. 925-700MB WARM ADVECTION INTO OVER THIS FRONT SPREADS ACROSS IA/ SOUTHERN MN THRU THE NIGHT. RATHER IMPRESSIVE 700-500MB FN CONVERGENCE SIGNAL SPREADS INTO THE SOUTHWEST SIDE OF THE FCST AREA AFTER MIDNIGHT. INCREASING MOISTURE/LIFT ABOVE 850MB INTO THE SOUTHWEST SIDE OF THE FCST AREA WILL BATTLE THE EASTERLY FEED OF DRIER AIR IN THE SFC-850MB LAYER. IMPROVING MODEL CONSENSUS CLIPS THE MAINLY THE NORTHEAST IA PORTION OF THE FCST AREA WITH SHRA/TSRA LATER TUE NIGHT. CONTINUED 20-60 PERCENT SHRA/TSRA CHANCES THERE LATE TUE NIGHT WITH THE HIGH/DRIER AIR GENERALLY WINNING OUT ELSEWHERE. WITH THE RAIN COOLING OFF THE AIRMASS THIS AFTERNOON TRENDED TOWARD COOLER OF GUIDANCE LOWS TONIGHT. USED A BLEND OF THE GUIDANCE FOR HIGHS/LOWS TUE/TUE NIGHT. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 316 PM MON AUG 4 2014 MAIN CONCERNS FOR WEDNESDAY THROUGH THURSDAY NIGHT...PASSING SHRA/ TSRA CHANCE WEDNESDAY...SMALL SHRA/TSRA CHANCES WEST/SOUTH WED NIGHT THRU THU NIGHT...TEMPERATURES THRU THE PERIOD. IMPROVING MODEL CONSENSUS FOR LONGWAVE RIDGING TO BUILD OVER THE UPPER MIDWEST WED INTO THU NIGHT...HOWEVER SOME DETAIL DIFFERENCES REMAIN WITH THE EVOLUTION OF THE ND/SASKAT SHORTWAVE ENERGY AS IT MOVES THE MID LEVEL RIDGE AXIS. TREND OF 04.12Z IS WEAKER WITH THIS FEATURE AS IT PUSHES INTO THE UPPER MIDWEST. OVERALL FCST CONFIDENCE IN THE WED THRU THU NIGHT PERIOD IS AVERAGE TO GOOD. WITH STRONGER MID LEVEL RIDGING PROGGED OVER THE UPPER MIDWEST THIS PERIOD...SIGNAL IS FOR CAN HIGH PRESSURE OVER THE GREAT LAKES TO HOLD AND EXERT ITS INFLUENCE OF DRIER LOW LEVEL AIR ACROSS WI AND NEARBY AREAS FOR WED-THU NIGHT. STRONGER 925-700MB WARM ADVECTION AND 700-500MB FN CONVERGENCE FROM LATE TUE NIGHT SLIDES ACROSS THE SOUTHWEST END OF THE FCST AREA WED. CONTINUED WITH SOME HIGHER SHRA/ TSRA CHANCES ACROSS ROUGHLY THE SOUTHWEST 1/4 OF THE FCST AREA WED. WITH PERSISTENT CLOUDS AND EASTERLY FLOW UNDER THE RAIN WED...TEMPS ACROSS THE SOUTHWEST SIDE OF THE FCST AREA TO STAY ON THE COOL SIDE. SOME SUNSHINE AND DRIER AIR WILL ALLOW TEMPS ACROSS THE NORTHEAST 2/3 OF THE FCST AREA TO CLIMB INTO THE 75-80F RANGE. THE CANADIAN HIGH THEN LOOKS TO DOMINATE THE FCST AREA FOR WED NIGHT THRU THU NIGHT. SOME SIGNALS FOR WEAK LOWER LEVEL MOISTURE TRANSPORT AND WARM ADVECTION...IN CONJUNCTION WITH THE NORTHERN PLAINS SHORTWAVE TO SKIRT THE WESTERN EDGE OF THE HIGH DURING THIS PERIOD. LEFT SOME VERY SMALL SHRA/TSRA CHANCES ACROSS THE FAR SOUTHWEST AND WEST ENDS OF THE FCST AREA WED THRU THU NIGHT FOR NOW...MAINLY TO BLEND WITH THE NEIGHBORING GRIDS. USED A BLEND OF THE GUIDANCE LOWS/HIGHS FOR WED NIGHT THRU THU NIGHT...WITH TEMPS NEAR TO A BIT BELOW NORMAL UNDER EASTERLY FLOW OUT OF THE GREAT LAKES HIGH. FOR FRIDAY THROUGH MONDAY.../DAYS 4 TO 7/... MAIN CONCERNS THIS PERIOD...SHRA/TSRA CHANCES MONDAY...TEMPERATURES THROUGH THE PERIOD. 04.00Z/04.12Z MEDIUM RANGE MODELS HAVE TRENDED BACK TO STRONGER MID LEVEL RIDGING OVER THE NORTH-CENTRAL CONUS FRI THRU SUN...WITH THE MAIN STORM TRACK PUSHED NORTH INTO CAN. THIS HOWEVER DOES NOT LEAVE MUCH FOR RUN-TO-RUN CONSISTENCY COMPARED TO THE 03.12Z MODEL SUITE. STILL SOME SIGNAL FOR WEAK SHORTWAVES TO COME THRU THE RIDGING AND ACROSS THE REGION FRI-SUN BUT THESE INCONSISTENT AMONG THE MODELS. REASONABLE CONSISTENCY AMONG THE MODELS FOR A STRONGER TROUGH TO TRACK ACROSS CENTRAL CAN SUN NIGHT/MON...LOWERING HGTS AND SENDING A LOWER LEVEL TROUGH/FRONT INTO THE WESTERN GREAT LAKES. FCST CONFIDENCE IN THE DAY 4-7 PERIOD IS AVERAGE THIS CYCLE. THE STRONGER MID LEVEL RIDGING SIGNAL INTO THE NORTH CENTRAL CONUS LATER IN THE WEEK ALLOWS THE CANADIAN HIGH TO PERSIST OVER THE GREAT LAKES INTO SUNDAY. THIS HIGH LOOKS TO PROVIDE A CONTINUED EASTERLY FEED OF LOWER LEVEL DRY AIR INTO THE AREA...WITH BELOW NORMAL PW VALUES. MID CREW REMOVED RAIN CHANCES FROM FRI/SAT. THIS LOOKS GOOD WITH THE SFC HIGH AND DRIER LOW LEVEL AIRMASS...EVEN WITH MODELS SHOWING WEAK SHORTWAVES RIPPLING THRU THE MID LEVEL RIDGE. 04.12Z GFS/ECMWF TREND A BIT FASTER WITH THE TRAILING LOWER LEVEL TROUGH...AND SHRA/TSRA CHANCES INTO THE REGION SUN. LEFT THE SMALL CONSENSUS SHRA/TSRA CHANCES FOR SUN. DUE TO THE CONSISTENCY OF THE SIGNAL FOR FALLING HGTS MON AND A LOWER LEVEL TROUGH TO PUSH ACROSS THE REGION...SMALL -SHRA/TSRA CHANCES SUN NIGHT/MON REASONABLE. GIVEN THE EASTERLY FLOW OUT OF THE HIGH...MODEL/ ENSEMBLE CONSENSUS HIGHS/LOWS NEAR TO A BIT BELOW NORMAL FOR FRI THRU MON LOOK GOOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1032 PM CDT MON AUG 4 2014 FOG POTENTIAL THIS MORNING IS THE MAIN CONCERN. RECENT RAIN... LIGHT WINDS...CLEARING SKIES AND TEMPERATURE/DEWPOINT SPREADS THAT ARE NEAR SATURATED ALL POINT TO FOG FORMATION. THEREFORE...TAFS CONTINUE TO REFLECT VISIBILITIES DROPPING THROUGH THE NIGHT WITH POTENTIAL LIFR TO VLIFR VISIBILITIES AND CEILINGS BETWEEN 10-13Z. DAYTIME MIXING SHOULD GET RID OF ANY FOG AND LOW STRATUS BY 14Z...WITH VFR CONDITIONS PERSISTING THROUGH TUESDAY EVENING AS HIGH PRESSURE TAKES HOLD. LOOKING AHEAD...MAY HAVE TO DEAL WITH MORE FOG LATE TUESDAY NIGHT AT LSE. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && UPDATE...AJ SHORT TERM...RRS LONG TERM....RRS AVIATION...AJ
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 828 PM CDT MON AUG 4 2014 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029- 032>034-041>044-053>055-061-051200- MITCHELL-HOWARD-WINNESHIEK-ALLAMAKEE-FLOYD-CHICKASAW-FAYETTE- CLAYTON-WABASHA-DODGE-OLMSTED-WINONA-MOWER-FILLMORE-HOUSTON- TAYLOR-CLARK-BUFFALO-TREMPEALEAU-JACKSON-LA CROSSE-MONROE-JUNEAU- ADAMS-VERNON-CRAWFORD-RICHLAND-GRANT- 828 PM CDT MON AUG 4 2014 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST INTO CENTRAL WISCONSIN .DAY ONE...REST OF TONIGHT AREAS OF FOG ARE EXPECTED TO DEVELOP AFTER MIDNIGHT. VISIBILITIES COULD DROP TO 1/4 MILE AT TIMES. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY AREAS OF FOG ARE EXPECTED DURING THE TUESDAY MORNING COMMUTE. VISIBILITIES COULD DROP TO 1/4 MILE AT TIMES. THUNDERSTORMS ARE POSSIBLE TUESDAY NIGHT INTO WEDNESDAY MAINLY ACROSS NORTHEAST IOWA INTO FAR SOUTHERN WISCONSIN. HEAVY RAINFALL COULD RESULT FROM THESE STORMS. THUNDERSTORM CHANCES WILL BE SEEN THURSDAY NIGHT AND AGAIN SATURDAY INTO SUNDAY. SEVERE WEATHER IS NOT ANTICIPATED WITH THESE STORMS AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TUESDAY. .EMERGENCY MANAGEMENT COORDINATION... NO WEBINAR IS SCHEDULED. AJ
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LA CROSSE WI 637 PM CDT MON AUG 4 2014 WIZ017-050030- TAYLOR- 637 PM CDT MON AUG 4 2014 ...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHERN TAYLOR COUNTY THROUGH 730 PM CDT... AT 635 PM CDT...A LINE OF STRONG THUNDERSTORMS WAS ALONG A LINE EXTENDING FROM JUMP RIVER TO RIB LAKE...AND MOVING SOUTH AT 10 MPH. WINDS IN EXCESS OF 30 MPH ARE POSSIBLE WITH THESE STORMS. TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THESE STORMS...AND MAY CAUSE LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS. LOCATIONS IMPACTED INCLUDE... RIB LAKE...CHELSEA...WESTBORO...JUMP RIVER...GOODRICH...DONALD... HANNIBAL...KATHRYN LAKE...THE MONDEAUX FLOWAGE...PERKINSTOWN...WOOD LAKE AND ESADORE LAKE. LAT...LON 4537 9004 4516 9005 4521 9093 4538 9093 TIME...MOT...LOC 2335Z 028DEG 10KT 4526 8999 4532 9091 AJ
The national radar mosaic for the moment the first event began.
1 dense fog. Local standard time, as filed.
One person was injured when a car rolled off a Rochester road. The automated weather observing equipment at the Rochester airport indicated dense fog with a visibility of a half mile or less was occurring at the time of the accident.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2014Every state in 2014This day in weather historyWarnings in Minnesota, August 2014
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: 536682.