Heavy Snow, St. Clair
- When
- December 2, 4:00 AM EST to December 3, 8:00 AM EST
- Where
- St. Clair forecast zone
- Reported by
- TRAINED SPOTTER
- Coordinates
- 42.931, -82.664 (the zone’s center; the record gives no point)
Heavy Snow in Michigan, December 2 to 3, 2002
An arctic cold front swept through the Great Lakes during the evening of the 2nd and into the early morning hours of the 3rd. A band of snowfall accompanied this front.
Where it happened
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.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 1
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.
What happened
The episode as NWS DTX wrote it up.
An arctic cold front swept through the Great Lakes during the evening of the 2nd and into the early morning hours of the 3rd. A band of snowfall accompanied this front. Most of central Lower Michigan received 1 to 2 inches from the front, with southern Lower Michigan receiving 3 to 5 inches. A band of heavier snow fell across western St Clair county. Northeasterly winds off of Lake Huron may have contributed to the heavier snowfall. While most of the snow ended across the region early in the evening on the 2nd, north-northeasterly winds and very cold air allowed a band of heavy lake effect snow to continue affecting far eastern St Clair county and portions of the Thumb into the early morning hours of the 3rd. By the time the snow ended, snowfall accumulated to 11 inches across the eastern portion of St Clair county, including the city of Port Huron. The western half of the county reported snowfall amounts around 8 inches. Snowfall amounts were generally 6 inches or less across the eastern half of the thumb region. This was the second significant lake effect snowfall in the city of Port Huron in less than a week (refer to November Storm Data for information on the first event). With the snowfall beginning during the overnight hours across Flint and the tri cities and around rush hour in metro Detroit, roads had become quite slippery by the morning of the 2nd. Hundreds of traffic accidents across eastern Michigan were claimed to have resulted from slippery roads. At least a dozen of those accidents resulted in injury. The only reported deaths from the traffic accidents was that of an elderly couple in Shiawassee County. Nearly 170 flights had to be cancelled at Detroit Metro Airport due to the snowfall.
What forecasters said that day
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 Detroit, MI wrote its last area forecast discussion before the first event at Dec 2, 3:52 AM EST, 8 minutes earlier.
Area forecast discussion, Dec 2, 3:52 AM EST, 8 minutes before
SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
352 AM EST MON DEC 2 2002
COMPLICATED FORECAST FOR TODAY WITH AN ARCTIC FRONT MOVING SOUTH
ACROSS THE FORECAST AREA THIS MORNING. THERE HAS BEEN AN AREA OF
LIGHT SNOW ACCOMPANYING THE FRONT AS IT MOVES SOUTH ACROSS THE
REGION. NOT TOO MUCH SNOW HAS BEEN ACCUMULATING WITH SNOW AMOUNTS
GENERALLY LESS THAN AN INCH. THE INTENSITY OF THE SNOWFALL SHOULD
INCREASE THIS MORNING AS A COUPLE FACTORS COME INTO PLAY. SOUTHEAST
MICHIGAN GETS INTO THE RIGHT REAR QUADRANT OF A 100 KNOT 500MB JET
THIS MORNING AND THIS WILL AID IN INCREASING THE LIFT AS THE FRONT
DROPS THROUGH THE SOUTHERN COUNTIES. RATHER IMPRESSIVE 850MB
FRONTOGENESIS OCCURS ACROSS THE SOUTHERN COUNTIES THIS MORNING AND
EARLY AFTERNOON AND THIS WILL ALSO AID IN THE SNOW DEVELOPMENT.
RADARS TO OUR WEST ARE BEGINNING TO LIGHT UP. THIS SHOULD BE THE
INFLUENCE OF THE JET COMING TO PLAY. THE AIRMASS ACCOMPANYING THE
FRONT WILL BE RATHER DRY WITH SPECIFIC HUMIDITIES BETWEEN 1 AND 2.
SINCE WE SHOULD ONLY SEE AROUND 6 HOURS OF ACCUMULATING SNOW I WILL
HAVE 1 TO 2 INCHES OF SNOW IN THE FORECAST FOR THE I94 CORRIDOR AND
LESSOR AMOUNTS NORTH.
FORECAST PROBLEM THEN SHIFTS TO LATER TODAY AND TONIGHT. WITH WINDS
ON LAKE HURON FROM THE NORTH TO NORTHEAST LATER TODAY AND 850MB
TEMPERATURES DOWN AROUND MINUS 20C... LAKE EFFECT SNOW SEEMS TO BE A
SURE BET. INVERSION HEIGHTS ARE FORECAST TO BE AROUND 7500KT LATER
TODAY AND THEN DROPPING TO NEAR 5K FEET TONIGHT. MODELS TENDS TO
UNDER-ESTIMATE THE INVERSION HEIGHTS AND THUS THEY SHOULD BE HIGHER.
GREAT LAKES ETA IS SHOWING GOOD LOW LEVEL CONVERGENCE OCCURRING FROM
ABOUT 21Z THROUGH 09Z ALONG WITH GOOD UPWARD MOTION OCCURRING AT
850MB. BELIEVE A SCENARIO SIMILAR TO LAST TUESDAY/S LAKE EFFECT
SNOWFALL COULD SET UP. ONLY QUESTION WILL BE IS WHERE THE DOMINATE
BAND WILL COME ASHORE. GREAT LAKES ETA POINTS TO NEAR PORT HURON
AGAIN... BUT ALSO HAS ANOTHER BAND IN HURON COUNTY. WILL PUT UP A
WINTER STORM WATCH FOR HEAVY LAKE EFFECT SNOWFALL FOR LATE TODAY AND
TONIGHT FOR HURON...SANILAC AND ST CLAIR COUNTIES. JUST A MINOR
CHANGE IN THE WIND DIRECTION... ONLY 20-30 DEGREES... WILL MAKE A
BIG DIFFERENCE IN WHERE THE LAKE EFFECT SNOW WILL COME ASHORE.
FLOW BACKS TO THE NORTHWEST LATE TONIGHT AND THIS SHOULD SHIFT ALL
THE LAKE EFFECT SNOW OFF THE THUMB LEAVING JUST FLURRIES IN IT
WAKE.
SEVERAL SHORT WAVES WILL MOVE THROUGH SOUTHEAST MICHIGAN FOR THE
WEDNESDAY THROUGH THE WEEKEND TIME FRAME. SHOULD BE SOME SNOW
SHOWERS ACCOMPANYING EACH WAVE... BUT WITH THE UPPER FLOW REMAINING
FROM THE WEST AND NORTHWEST MOISTURE WILL BE RATHER LIMITED. WILL
CONTINUE THE CHANCE POPS FROM PREVIOUS FORECAST FOR THURSDAY THROUGH
SUNDAY.
.DTX...WINTER STORM WATCH FOR POTENTIALLY HEAVY LAKE EFFECT SNOW
LATE TODAY AND TONIGHT FOR HURON...SANILAC... AND ST CLAIR
COUNTIES.
KEYESHazardous weather outlook, Dec 1, 7:20 PM EST, 8 hours 40 minutes before
MIZ047>049-053>055-060>063-068>070-075-076-082-083-020945- HAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 720 PM EST SUN DEC 1 2002 CORRECTED FOR SPOTTER ACTIVATION INFORMATION THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST MICHIGAN .DAY ONE.. SNOW WILL FALL ACROSS ALL OF SOUTHEAST MICHIGAN TONIGHT IN RESPONSE TO AN ARCTIC FRONT CROSSING THE REGION. THE SNOW TAPER TO FLURRIES THIS EVENING ACROSS THE SAGINAW VALLEY AND THUMB WHERE ONE TO TWO INCH ACCUMULATIONS ARE LIKELY. BETWEEN I 69 AND M 59 PERIODS OF SNOW WILL CONTINUE TONIGHT YIELDING ONE TO TWO INCHES AS WELL. TO THE SOUTH IN METRO DETROIT AND POINTS SOUTH...THE SNOW WILL NOT DEVELOP UNTIL AROUND MIDNIGHT...WITH ABOUT AN INCH ACCUMULATING BY SUNRISE. IN ADDITION...BRISK SOUTHWEST WINDS WILL PRODUCE WIND CHILLS AROUND ZERO...AND COULD PRODUCE SOME MINOR BLOWING AND DRIFTING SNOW. .SPOTTER ACTIVATION... DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGER IMMEDIATELY. SPOTTERS ARE ENCOURAGED TO PHONE IN OR E-MAIL SNOWFALL REPORTS IF POSSIBLE TONIGHT AND MONDAY. .DAYS TWO THROUGH SEVEN... SNOW WILL CONTINUE TO FALL ACROSS DETROIT AND POINTS SOUTH MONDAY AS THE ARCTIC BOUNDARY SLOWS ITS MOVEMENT SOUTH. ADDITIONAL ACCUMULATIONS FOR METRO DETROIT AND POINTS SOUTH LOOK TO BE TWO TO FOUR INCHES. THERE IS SOME UNCERTAINTY AS TO THIS ACCUMULATION POTENTIAL. DRY AIR INITIALLY IN PLACE ACROSS THE SOUTH AS WELL AS DRY AIR NOSING IN FROM THE NORTH ON MONDAY MAY SERVE TO LIMIT ACCUMULATIONS. ON THE OTHER HAND...IF THE SYSTEM SHOULD BECOME MORE VIGOROUS THAN CURRENTLY EXPECTED...SNOWFALL COULD EXCEED FORECAST AMOUNTS. LATE MONDAY AFTERNOON INTO TUESDAY AFTERNOON...WINDS WILL SHIFT AROUND TO NORTH NORTHEAST ACROSS LAKE HURON...AS THE COLDEST AIR OF THE SEASON MOVES OVER THE WARM LAKE WATERS. LAKE EFFECT SNOW SHOWERS ARE EXPECTED LATE MONDAY AFTERNOON AND TUESDAY ACROSS THE LAKE HURON COUNTIES OF HURON...SANILAC AND ST CLAIR. CONSIDERABLE UNCERTAINTY PREVAILS WITH REGARD TO SNOWFALL ACCUMULATION. SOME FACTORS...SUCH AS THE EXTREMELY COLD TEMPERATURES SUPPORT THE DEVELOPMENT OF LAKE EFFECT SNOW BANDS CAPABLE OF PRODUCING HEAVY SNOW. ON THE OTHER HAND...CONSIDERABLE DRY AIR WILL BE IN PLACE AT HIGHER LEVELS OVER LAKE HURON HINDERING SNOWFALL DEVELOPMENT. FURTHERMORE...THE EXACT ALIGNMENT OF THESE SNOW BANDS WILL DETERMINE SNOWFALL ACCUMULATIONS. THE EXACT LOCATION OF THESE BANDS REMAINS TO BE SEEN. SUMMING UP...THERE IS THE POTENTIAL FOR LAKE EFFECT SNOW TO AFFECT THE LAKE HURON COUNTIES OF SOUTHEAST LOWER MICHIGAN MONDAY AFTERNOON INTO TUESDAY. HOWEVER...CONSIDERABLE UNCERTAINTY REMAINS AS TO THE SNOWFALL POTENTIAL. THEREFORE...STAY TUNED TO NOAA WEATHER RADIO...OR LOCAL MEDIA OUTLETS...FOR THE LATEST FORECAST INFORMATION FROM THE NATIONAL WEATHER SERVICE. YOU CAN ALSO OBTAIN THE LATEST FORECAST ON THE NATIONAL WEATHER SERVICE WEB SITE HTTP://WWW.CRH.NOAA.GOV/DTX/ (ALL LOWER CASE) OKEEFE
The radar
The national radar mosaic for the moment the first event began.
Event by event
1 heavy snow. Local standard time, as filed.
What these are
- Heavy Snow
- Snowfall reaching the local warning threshold without the other hazards of a winter storm.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
More
Every storm in Michigan in 2002Every state in 2002This day in weather historyWarnings in Michigan, December 2002
Sources
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: 5325880.