1 thunderstorm wind, as filed by the National Weather Service.
Every event with a place to put it. 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 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 Grand Rapids, MI wrote its last area forecast discussion before the first event at May 10, 2:10 PM EST, 1 hour 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 310 PM EDT THU MAY 10 2001 SHORT TERM DISCUSSION... CHALLENGES WILL MAINLY BE IN THE FIRST COUPLE PERIODS OF THE SHORT TERM (TON/FRI) AS A FRONTAL BOUNDARY WILL BE WORKING THROUGH THE FORECAST AREA. FRONTAL BOUNDARY AT PRESENT STRETCHES FROM NORTH CENTRAL WISCONSIN SOUTHWESTWARD INTO IOWA. THE BOUNDARY WILL SHIFT THROUGH SOUTHWEST MICHIGAN TOMORROW WITH HIGH PRESSURE BUILDING INTO THE AREA IN ITS WAKE FOR SATURDAY. ALOFT...FLAT BROAD CYCLONIC FLOW WILL AMPLIFY WITH TIME...WITH A UPPER TROF IN PLACE BY SATURDAY WHICH WILL RESULT IN A COOL DOWN. SHORT TERM MODELS ETA/NGM/AVN ALL SIMILAR WITH THE MAIN FEATURES AND AGAIN WILL USE A BLEND OF THE ETA AND THE AVN. TONIGHT...A RATHER COMPLEX CONVECTIVE SITUATION IN PLACE WITH MANY FEATURES TO WATCH. FIRST IS WHAT APPEARS TO BE AN OUTFLOW BOUNDARY ALOFT THAT STRETCHES EAST TO WEST ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA. THIS BOUNDARY WAS LAID DOWN FROM EARLY MORNING SHOWERS. CONVECTION IS CURRENTLY SEEN FIRING ALONG IT FROM NEAR SOUTH HAVEN TO LANSING. THIS WILL LIKELY DRIFT NORTH THIS EVENING. SECOND FEATURE TO KEY ON IS A CONVECTIVELY INDUCED VORT SEEN SPINNING ENE IN THE SAT PICS OVER CENTRAL ILLINOIS. THIS COULD BECOME A FOCUS FOR DEVELOPMENT THIS EVENING OVER NORTHERN ILLINOIS THAT WOULD ADVECT INTO SOUTHWEST LWR MI THIS EVENING. IN ADDITION...ANOTHER SHORTWAVE IS SEEN IN THE WATER VAPOR IMAGERY IN EASTERN SD/NE WHICH IS QUICKLY MOVING EAST IN THE ALMOST ZONAL FLOW ALOFT. THIS VORT IS ALREADY RESPONSIBLE FOR CONVECTION THAT IS TAKING PLACE OVER IOWA. THIS CONVECTION BASED ON DEEP LAYER THERMAL WIND FIELDS (850-300MB) WILL TRY TO MOVE EAST TOWARD LOWER MICHIGAN AS WELL. SO...WILL OBVIOUSLY BE CARRYING CATEGORICAL POPS FOR BOTH SHOWERS AND THUNDERSTORMS TONIGHT. WILL MAINTAIN A MENTION OF HEAVY RAINFALL POSSIBLE FORECAST AREA WIDE GIVEN THE FACT THAT TRAINING OF CELLS WILL BE LIKELY IN THE SOUTHWEST FLOW. PRECIPITABLE WATER VALUES APPROACH 1.5 INCHES THIS EVENING WHICH IS SUBSTANTIAL FOR THIS TIME OF YEAR. MAIN SEVERE THREAT WOULD BE HAIL WITH FREEZING LEVEL HEIGHTS AROUND 10000 FT. IN ADDITION...STRONG SURFACE WIND GUSTS WOULD BE ANOTHER THREAT AS THE 850MB LLJ IMPINGES ON THE AREA AT A STRENGTH OF ABOUT 35 KNOTS. ON FRIDAY...FRONT WILL PROGRESS THROUGH THE FORECAST AREA FROM NORTHWEST TO SOUTHEAST. BEST LOWER TROP CONVERGENCE WILL SHIFT SOUTHEAST OF THE AREA AS WELL WITH THE FRONT...SO PRECIPITATION SHOULD COME TO AN END FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY. GOOD UPPER LEVEL DIVERGENCE THAT WILL BE IN PLACE TONIGHT SHIFTS EASTWARD TOMORROW AS WELL...SO MUCH LESS FAVORABLE DYNAMICS TOMORROW IN COMPARISON WITH TONIGHT. STILL...MOISTURE POOLED ALONG THE BOUNDARY AND WHAT CONVERGENCE IS LEFT ALONG IT WILL COMBINE TO PRODUCE SHOWERS AND THUNDERSTORMS. WILL CONFINE THE MENTION OF PRECIPITATION TO THE MORNING IN THE NORTH...AND ENDING IN THE AFTERNOON IN THE SOUTH. FRIDAY NIGHT...RIDGING WILL BE BUILDING INTO THE AREA WITH NORTHWEST FLOW IN PLACE. MOISTURE WILL BE SCOURED OUT...AND IT APPEARS SKIES WILL BECOME MOSTLY CLEAR. A MUCH COOLER NIGHT EXPECTED...WITH TEMPS DROPPING TO AROUND 40. FROST MAY NOT BE A BIG PROBLEM WITH A BIT OF A GRADIENT REMAINING IN PLACE WHICH WILL KEEP THE WIND UP. SATURDAY WILL USE A BECOMING PARTLY CLOUDY WORDING WITH SOME DIURNAL CU EXPECTED...ESPECIALLY INLAND AND SOME CIRRUS MOVING THROUGH IN THE NORTHWEST FLOW ALOFT. SATURDAY NIGHT SURFACE RIDGING STILL IN THE AREA...BUT IT WILL BE DRIFTING SOUTH WHICH WILL ALLOW SOME WESTERLY RETURN FLOW TO DEVELOP LATE. THIS MAY LIMIT THE FROST THREAT A LITTLE BIT AS WELL ON SATURDAY NIGHT. WILL STAY CLOSE TO THE NGM MOS NUMBERS. DUKESHERER EXTENDED FORECAST DISCUSSION... EXPECT SEASONABLE TEMPERATURES WITH THE MAIN PRECIPITATION THREAT FOR THE 5 DAY PERIOD COMING ON TUE/WED. MOST OF THE COOLER AIR ASSOCIATED WITH DEVELOPING UPPER LEVEL TROUGH/CLOSED LOW OVER NEW ENGLAND WILL BE CONCENTRATED TO OUR EAST LATE IN THE WEEKEND AND EARLY NEXT WEEK. SHORTWAVE MOVING SEWD OUT OF WRN ONTARIO COMBINED WITH WARM ADVECTION PATTERN MAY BRING WIDELY SCATTERED SHOWERS TO THE FORECAST AREA SUN AFTERNOON/EVENING...ALTHOUGH EXPECT MOST OF THIS ACTIVITY TO OCCUR ACROSS NRN AND ERN LOWER MICHIGAN PER 12Z AVN. SWRLY SFC WINDS WILL BRING WARMER AIR INTO THE REGION FOR MON...THEN NEXT SHORTWAVE WILL START TO AFFECT THE STATE BY TUE. MODELS DIVERGE ON THE EVOLUTION OF THIS SYSTEM AND THE DEGREE TO WHICH COOLER AIR WILL FOLLOW SYSTEM WED/THU. WILL LEAN TOWARD MRF ENSEMBLE MEANS AND BRING ANOTHER PERIOD OF COOLER AIR IN FOR DAYS 6 AND 7 WITH THE THREAT FOR INSTABILITY SHOWERS ON WED. GREENE .GRR...NONE.
The Grand Rapids radar (KGRR), 14 km away, was scanning. The volume nearest the first event began at 20:22 UTC.
1 thunderstorm wind. Local standard time, as filed.
An isolated severe thunderstorm produced an estimated wind gust to 60 m.p.h. as well as 0.88 inch diameter hail in Alto at 3:20 p.m.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2001Every state in 2001This day in weather historyWarnings in Michigan, May 2001
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: 5252145.