585
FXUS63 KGRB 151137
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
537 AM CST WED JAN 15 2025
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
KEY MESSAGES
- SUBZERO WIND CHILLS ARE EXPECTED ACROSS THE AREA THIS MORNING.
- AN UPPER LEVEL DISTURBANCE WILL BRING LIGHT SNOW TO THE REGION
THIS EVENING. A DUSTING TO AN INCH IS EXPECTED.
- CONFIDENCE IS INCREASING IN POTENTIAL FOR DANGEROUSLY COLD WIND
CHILLS SUNDAY THROUGH TUESDAY, ESPECIALLY DURING THE EARLY
MORNING HOURS.
DISCUSSION
ISSUED AT 308 AM CST WED JAN 15 2025
SHORT TERM...TODAY...TONIGHT...AND THURSDAY
SOMEWHAT MILDER WEATHER IS EXPECTED TODAY, AS WINDS
SHIFT TO THE SOUTHWEST. SKIES WILL START OUT SUNNY, BUT CLOUDS
WILL INCREASE FROM WEST TO EAST IN THE AFTERNOON AS AN UPPER
LEVEL TROUGH AND ASSOCIATED SURFACE FRONT APPROACH. LIGHT SNOW
SHOULD ARRIVE IN FAR NORTHCENTRAL WISCONSIN BEFORE DUSK, AND
ACROSS THE REMAINDER OF THE AREA DURING THE EVENING HOURS.
SNOWFALL FROM THIS SYSTEM SHOULD BE LESS THAN AN INCH, BUT SUFFICIENT
TO PRODUCE SLICK ROADS AND SIDEWALKS. THE SNOW WILL END OVERNIGHT,
THOUGH LAKE EFFECT SNOW SHOWERS MAY CONTINUE INTO THURSDAY MORNING
IN VILAS COUNTY.
TEMPERATURES WILL BE WARMER THAN YESTERDAY, THOUGH A STEADY WIND
WILL MAKE IT FEEL COLDER THAN IT ACTUALLY IS. HIGHS WILL BE JUST A
FEW DEGREES BELOW NORMAL. CLOUDS AND A GUSTY WIND WILL PRODUCE
STEADY OR SLOWLY RISING TEMPERATURES TONIGHT. THURSDAY WILL BE THE
WARMEST DAY IN THE PAST WEEK OR SO, WITH HIGH TEMPERATURES FIVE
TO TEN DEGREES ABOVE NORMAL.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY
CONFIDENCE IS INCREASING IN POTENTIAL FOR DANGEROUSLY COLD WIND
CHILLS EARLY NEXT WEEK. OTHERWISE, SNOW CHANCES REMAIN LIMITED TO
LAKE EFFECT ACROSS THE SNOWBELTS GIVEN A GENERAL LACK OF IMPACTFUL
SYNOPTIC SYSTEMS IN THE EXTENDED.
LAKE EFFECT SNOW CHANCES... A QUICK SHOT OF LIGHT LAKE EFFECT
SNOW WILL BE POSSIBLE ACROSS FAR NORTHERN WISCONSIN FRIDAY
AFTERNOON AND EVENING AS A CLIPPER SYSTEM PASSES TO OUR NORTH.
HOWEVER, AMOUNTS SHOULD BE HELD DOWN TO LESS THAN AN INCH DURING
THIS TIME GIVEN DRY FROPA AND WEAK FORCING. POST-FRONTAL WINDS
THEN VEER TO NORTHWESTERLY, KICKING OFF MORE PERSISTENT LAKE
EFFECT CHANCES THROUGH EARLY NEXT WEEK. ENSEMBLES CURRENTLY SHOW
AROUND A 50 TO 70 PERCENT CHANCE OF NORTHERN VILAS COUNTY PICKING
UP AN INCH OF LIGHT, FLUFFY SNOW THROUGH SUNDAY MORNING. SOME
LONG-RANGE GUIDANCE SHOWS A LAKE EFFECT BAND OVER LAKE MICHIGAN
MAKING IT INTO THE DOOR PENINSULA SUNDAY AND MONDAY, ALTHOUGH
SUSPECT THAT IT WILL STAY MOSTLY OFFSHORE GIVEN WESTERLY WIND
COMPONENT.
TEMPERATURES/WIND CHILLS... MAIN FORECAST CONCERNS REVOLVE AROUND
GROWING POTENTIAL FOR DANGEROUS COLD LATE THIS WEEK INTO EARLY
NEXT WEEK. AN ARCTIC HIGH WILL DROP DOWN ACROSS THE US/CANADA
BORDER SUNDAY MORNING, USHERING IN 850 MB TEMPERATURES OF -30 TO
-32C (~FIRST PERCENTILE COMPARED TO CLIMATOLOGY). RESULT WILL BE
HIGH TEMPERATURES FAILING TO HIT ZERO DEGREES ACROSS CENTRAL AND
NORTH-CENTRAL WISCONSIN MONDAY AND TUESDAY. LIKEWISE,
PROBABILISTIC GUIDANCE CURRENTLY SHOWS AN 80 TO 90 PERCENT CHANCE
THAT CENTRAL AND NORTH-CENTRAL WISCONSIN WILL HIT WIND CHILLS
BELOW -30 DEGREES EARLY MONDAY AND TUESDAY MORNINGS. THOUGH
EARLY IN THE GAME, COLD WEATHER HEADLINES APPEAR LIKELY DURING
THESE TIMEFRAMES; BIGGEST QUESTION WILL BE WHETHER OR NOT
WARNINGS WILL BE NECESSARY.
AVIATION
FOR 12Z TAF ISSUANCE
ISSUED AT 537 AM CST WED JAN 15 2025
VFR CONDITIONS AND CLEAR SKIES ARE EXPECTED THROUGH
THE EARLY AFTERNOON HOURS, THEN AN UPPER LEVEL DISTURBANCE WILL
BRING INCREASING CLOUDS AND A CHANCE OF LIGHT SNOW NORTH OF A RRL
TO IMT LINE TOWARDS DUSK.
LIGHT SNOW AND MVFR CONDITIONS ARE EXPECTED ACROSS THE REGION
TONIGHT. FLIGHT CONDITIONS SHOULD IMPROVE THURSDAY, WITH VFR
CEILINGS BY AFTERNOON IN MOST AREAS.
GRB WATCHES/WARNINGS/ADVISORIES
NONE.
DISCUSSION.....RDM/GOODIN
AVIATION.......RDM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page