1 waterspout, as filed by the National Weather Service.
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 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 Marquette, MI wrote its last area forecast discussion before the first event at Sep 30, 10:03 AM EST, 12 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1103 AM EDT TUE SEP 30 2003 WATER VAPOR IMAGERY AND RUC/ETA SHOWING A CLOSED LOW EMBEDDED IN A LONGWAVE TROUGH OVER ONTARIO AND THE UPPER GREAT LAKES REGION. A NUMBER OF WEAK SHORTWAVE ARE ROTATING THROUGH THE BASE OF THIS TROUGH. THE FIRST IS OVER THE U.P. THIS MORNING GENERATING SCATTERED SHOWERS. COLD AIR ADVECTING OVER THE REGION ON THE BACK SIDE OF THE TROUGH IS LOWERING THE 850MB TEMPERATURE TO -7C WHEREAS THE LAKE SURFACE TEMPERATURE REMAINS +8C. THIS SUGGEST A DELTA-T THAT IS CONDUCIVE TO LAKE EFFECT SNOWS...WHICH IS BEING GENERATE OVER THE NORTHERN U.P. A LAKE EFFECT SNOW BAND EXTENDS FROM MANITOU ISLAND TO THE PICTURE ROCK AREA. RUC/ETA SHOWING THE DELTA-TS WILL REMAIN AROUND 13C THIS AFTERNOON. 900-800MB RH WILL BE AROUND 80 PERCENT THROUGH THE AFTERNOON. LOW LEVEL CONVERGENCE WILL BE WEAK THIS AFTERNOON. HOWEVER...WITH THE DELTA-TS...THE SHORTWAVE OVER THE FORECAST AREA...AND AVAILABLE LOW LEVEL MOISTURE...LAKE EFFECT PRECIPITATION WILL CONTINUE THROUGH THE AFTERNOON. SOUNDING FORECASTS SHOWING ON A SHALLOW LAYER OF ABOVE FREEZING TEMPERATURES NEAR THE SURFACE. THIS SHOULD BE WARM ENOUGH TO MELT SOME OF THE SNOW. A SCATTERED MIX OF RAIN AND SNOW WILL CONTINUE OVER THE NORTH PART OF THE AREA THIS AFTERNOON. A FEW OF THE COUNTIES ARE SHOWING TEMPERATURES A LITTLE ABOVE GUIDANCE...SO WILL TWEAK A FEW TEMPERATURES. .MQT WATCHES/WARNINGS/ADVISORIES...NONE. DLG
MIZ001>007-009>014-084-085-011200- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MARQUETTE MI 535 AM EDT TUE SEP 30 2003 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL UPPER MICHIGAN. .DAY ONE...TODAY AND TONIGHT SCATTERED RAIN AND SNOW SHOWERS TODAY WILL CHANGE TO NUMEROUS SNOW SHOWERS TONIGHT OVER THE HIGHER TERRAIN OF THE WESTERN HALF OF UPPER MICHIGAN. SNOW ACCUMULATIONS OF UP TO TWO INCHES ARE POSSIBLE BY LATE TONIGHT. TEMPERATURES WILL FALL BELOW FREEZING TONIGHT OVER PORTIONS OF SOUTHWEST AND SOUTH CENTRAL UPPER MICHIGAN. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY SNOW SHOWERS WILL PRODUCE MINOR SNOW ACCUMULATIONS OVER HIGHER TERRAIN AREAS WEDNESDAY AND WEDNESDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. ADDITIONAL WEATHER INFORMATION MAY BE OBTAINED AT THE FOLLOWING URL: HTTP://WWW.CRH.NOAA.GOV/MQT (ALL LOWER CASE) JLA
1 waterspout. Local standard time, as filed.
Two waterspouts were sighted just northeast of the North Light on Grand Island. These waterspouts were formed by very cold air flowing over the relatively warmer waters of central Lake Superior.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Lake Superior in 2003Every state in 2003This day in weather history
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: 5336830.