939
FXUS63 KGRB 201159
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
559 AM CST MON JAN 20 2025
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
KEY MESSAGES
- WIND CHILLS OF 20 TO 40 DEGREES BELOW ZERO ARE EXPECTED AT TIMES
THROUGH WEDNESDAY MORNING. THE LOWEST WIND CHILLS WILL OCCUR
MONDAY NIGHT INTO TUESDAY MORNING WHEN WIND CHILLS AS LOW AS 40
BELOW ZERO WILL BE POSSIBLE.
- AN EXTREME COLD WARNING IS IN EFFECT FOR NORTH-CENTRAL WISCONSIN
THROUGH NOON TUESDAY.
- A COLD WEATHER ADVISORY IS IN EFFECT FOR CENTRAL AND NORTHEAST
WISCONSIN THROUGH MIDNIGHT TONIGHT. AN EXTREME COLD WARNING IS
THEN IN EFFECT FROM MIDNIGHT TONIGHT THROUGH NOON TUESDAY.
- A WARMING TREND WILL BEGIN ON WEDNESDAY, LASTING INTO THE
WEEKEND.
DISCUSSION
ISSUED AT 317 AM CST MON JAN 20 2025
SHORT TERM...TODAY...TONIGHT...AND TUESDAY
FORECASTING CLOUD COVER AND ANY EFFECT ON SURFACE TEMPERATURES ARE
THE MOST CHALLENGING PART OF THIS FORECAST. MOST OF THE CLOUDINESS
SHOULD BE DOWNWIND OF THE LAKES, BUT THERE WILL PROBABLY BE SCATTERED
LOW CLOUDS AT TIMES ANYWHERE. THERE COULD BE A PERIOD OF MIDDLE
CLOUDS THIS EVENING AS WARM ADVECTION BEGINS IN THE MID LEVELS
(EVEN THOUGH COLD ADVECTION WILL CONTINUE IN THE LOW LEVELS THROUGH
TUESDAY MORNING).
THE FOX VALLEY AND LAKESHORE COUNTIES COULD GET A FEW DEGREES ABOVE
ZERO THIS AFTERNOON, BUT OTHERWISE AIR TEMPERATURES SHOULD REMAIN
BELOW ZERO TODAY THROUGH TUESDAY NIGHT OVER ALL OF THE REGION.
THIS WILL LIKELY BE THE COLDEST STRECTH OF WEATHER SINCE THE LAST
TWO DAYS OF JANUARY 2019. NWS LA CROSSE HAS A NICE WRITE UP OF
THAT EVENT AT WEATHER.GOV/ARX/JAN3019.
LONG TERM...TUESDAY NIGHT THROUGH SUNDAY
LONG-TERM FOCUS GRADUALLY DIVERGES FROM COLD-RELATED IMPACTS AS
TEMPERATURES MODERATE BY WEDNESDAY AFTERNOON. ARCTIC AIR SHOULD
THEN BE SHUNTED OFF TO THE EAST, WITH COLD WEATHER HEADLINES
LIKELY COMING TO AN END BY 12Z WEDNESDAY. SNOW CHANCES REMAIN
ALMOST NEGLIGIBLE, BEST WEDNESDAY INTO THURSDAY AS A CLIPPER
PASSES THROUGH THE GREAT LAKES.
TEMPERATURES/WIND CHILLS... COLD AIR CORE SLIDES INTO THE OHIO
RIVER VALLEY TUESDAY EVENING, RESULTING IN A GRADUAL UPTICK IN
TEMPERATURES/WIND CHILLS INTO WEDNESDAY. THIS BEING SAID, A COLD
WEATHER ADVISORY WILL LIKELY STILL BE WARRANTED TUESDAY
NIGHT/WEDNESDAY MORNING AS WIND CHILLS DIP DOWN BETWEEN 20 AND 30
BELOW ZERO. WINDS THEN BACK TO SOUTHERLY BY MID-DAY WEDNESDAY,
USHERING IN A POTENT PUSH OF WAA AS SURFACE RIDGE BUILDS OVER THE
GREAT LAKES. RESULT WILL BE HIGH TEMPERATURES REBOUNDING TO THE
MID TEENS TO LOW 20S ABOVE ZERO, THOUGH STILL A FEW DEGREES BELOW
AVERAGE.
LIGHT SNOW CHANCES... ANOTHER SHORTWAVE IN THE 500 MB WAVE TRAIN
WILL DRAG A CLIPPER LOW THROUGH THE UPPER GREAT LAKES WEDNESDAY
INTO THURSDAY, BRINGING WIDESPREAD CHANCES FOR LIGHT SNOW TO THE
FORECAST AREA. SNOW LOVERS MAY NEVERTHELESS WANT TO AVERT THEIR
GAZE, AS SNOWFALL AMOUNTS SHOULD BE HELD DOWN TO LESS THAN AN
INCH AS SYNOPTIC SETUP STRUGGLES TO ORGANIZE AND MOISTURE REMAINS
VIRTUALLY NONEXISTENT. THE SNOW DROUGHT WILL THUS CONTINUE LIKELY
THROUGH THE END OF THE MONTH GIVEN A GENERAL LACK OF IMPACTFUL
SYNOPTIC SYSTEMS.
AVIATION
FOR 12Z TAF ISSUANCE
ISSUED AT 559 AM CST MON JAN 20 2025
VFR CONDITIONS ARE GENERALLY EXPECTED TODAY THROUGH TUESDAY
ACROSS THE REGION. THERE COULD BE SCATTERED CLOUDS WITH BASES
AROUND 3000 FEET THAT COULD PRODUCE SNOW FLURRIES. THERE COULD
ALSO BE A PERIOD OF MIDDLE CLOUDS THAT MOVE ACROSS THE AREA THIS
EVENING.
GRB WATCHES/WARNINGS/ADVISORIES
EXTREME COLD WARNING UNTIL NOON CST TUESDAY FOR WIZ005-010>012-
018-019.
COLD WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ013-
020>022-030-031-035>040-045-048>050-073-074.
EXTREME COLD WARNING FROM MIDNIGHT TONIGHT TO NOON CST TUESDAY
FOR WIZ013-020>022-030-031-035>040-045-048>050-073-074.
DISCUSSION.....RDM/GOODIN
AVIATION.......RDM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page