Area Forecast Discussion
Issued by NWS Green Bay, WI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
955
FXUS63 KGRB 060908
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
408 AM CDT FRI MAY 6 2016

FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 408 AM CDT FRI MAY 6 2016

WARM AIR ADVECTION AHEAD OF AN APPROACHING COLD FRONT WILL RULE
OVER THE WESTERN GREAT LAKES TODAY. THIS WARM AIR ADVECTION WILL
CAUSE DAYTIME HIGHS AWAY FROM LAKE MICHIGAN TO SOAR INTO THE UPPER
70S TO LOWER 80S. IN ADDITION A TIGHTENING PRESSURE GRADIENT WILL
LEAD TO SOME GUSTY WINDS BY THE AFTERNOON AS DEEP MIXING BRINGS
DRIER AIR TO THE SURFACE THAN IS CURRENTLY FORECAST BY THE MODELS.
THEREFORE WILL CONTINUE TO KEEP DEW POINTS BELOW MOS GUIDANCE
VALUES...WITH RELATIVE HUMIDITIES DROPPING INTO THE 20 TO 30
PERCENT RANGE THIS AFTERNOON. THE WARM...DRY WEATHER COMBINED WITH
SOME HIGHER GUSTS THIS AFTERNOON WILL CAUSE ELEVATED FIRE DANGER
CONCERNS ACROSS THE AREA TODAY. ALTHOUGH INSTABILITY WILL INCREASE
TODAY GIVEN THE ABUNDANT WARMING...INSTABILITY WILL BE ELEVATED
WITH RAIN NOT EXPECTED TO DEVELOP UNTIL THE COLD FRONT ARRIVES
TONIGHT AND PROVIDES A LIFTING MECHANISM FOR THE ELEVATED
INSTABILITY.

THE COLD FRONT WILL SWEEP THROUGH TONIGHT...BRINGING SHOWERS AND
THUNDERSTORMS TO THE WESTERN GREAT LAKES THROUGH SATURDAY MORNING.
INSTABILITY WITH THIS FRONT WILL BE RELATIVELY MEAGER...WITH
MUCAPES OF 500 TO 1000 J/KG. GIVEN THE ELEVATED NATURE OF THE CAPE
AND THE FRONT MOVING THROUGH WELL AFTER PEAK HEATING THE
THUNDERSTORMS ARE NOT EXPECTED TO BE STRONG WITH LITTLE TO
ANYTHING IN THE WAY OF HAIL OR WIND.

CLEARING SKIES AND COOLER TEMPERATURES ARE EXPECTED BEHIND THE
FRONT ON SATURDAY...HOWEVER HIGH TEMPERATURES ARE STILL EXPECTED
TO GET INTO THE 60S AS THE PUSH OF COLD AIR BEHIND THESE FRONTS
GETS LESS PROLIFIC AS SUMMER APPROACHES.

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 408 AM CDT FRI MAY 6 2016

THE LATEST ENSEMBLE MEANS CONTINUE TO INDICATE THAT SPLIT FLOW WILL
BE THE DOMINANT PATTERN ACROSS NORTH AMERICA FOR MUCH OF THE
UPCOMING WEEK.  FORECAST CONCERNS REVOLVE AROUND PRECIP POTENTIAL
NEXT WEEK WHEN AN UPPER LOW DRIFTS TOWARDS THE REGION.  THE MEDIUM
RANGE MODELS ARE IN RELATIVELY GOOD AGREEMENT THROUGH 00Z WED AND
WILL USE A BLEND OF THE GFS/ECMWF THRU THIS TIME.  THEREAFTER...WILL
LEAN ON THE ENSEMBLE MEANS.

SATURDAY NIGHT THRU SUNDAY NIGHT...MAINLY A QUIET PERIOD THANKS TO
NORTHWEST FLOW ALOFT AND A WEAK RIDGE OF HIGH PRESSURE AT THE
SURFACE.  A WEAK FRONT WILL TRY TO SAG INTO NORTHERN AND NORTHEAST
WISCONSIN ON SUNDAY BUT THE ATMOSPHERE LOOKS TOO DRY FOR ANY PRECIP.
WILL LIKELY SEE CLOUDS INCREASE LATE ON SUNDAY NIGHT AS LOW PRESSURE
MOVES ACROSS THE CENTRAL PLAINS.  LIGHT RAIN WILL PUSH INTO SOUTHERN
WISCONSIN LATE SUNDAY NIGHT BUT LIKELY FALL SHORT OF MOVING INTO
CENTRAL WI DUE TO AMPLE DRY AIR IN PLACE.  LITTLE CHANGE TO TEMPS
DURING THE PERIOD.

REST OF THE FORECAST...PERIODS OF RAIN WITH AN OCCASIONAL
THUNDERSTORM LOOK TO MOVE INTO THE REGION MONDAY THRU TUESDAY OF
NEXT WEEK.  UNLIKE THE PREVIOUS UPPER LEVEL SYSTEMS...THE DRY
AIRMASS WHICH WILL INITIALLY BE IN PLACE LOOKS TO GET OVERWHELMED BY
A SOUTHERLY FEED OF MOIST AIR. THERE MAY BE A RELATIVE LULL IN THE
PRECIP MIDWEEK AS THE FIRST UPPER LOW WEAKENS AND DEPARTS THE
REGION.  THEN A SECOND UPPER LOW WILL BRING MORE PRECIP BY THU AND
FRI OF NEXT WEEK.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1029 PM CDT THU MAY 5 2016

VFR CONDITIONS EXPECTED TO PREVAIL ACROSS THE AREA TONIGHT INTO
FRIDAY. A STRAY LIGHT SHOWER IS POSSIBLE OVER PARTS OF CENTRAL AND
NORTH CENTRAL WISCONSIN DURING THE TAF PERIOD. A PERIOD OF LLWS
CONDITIONS MAY DEVELOP LATE TONIGHT INTO FRIDAY MORNING OVER PARTS
OF CENTRAL AND NORTH CENTRAL WISCONSIN WHICH INCLUDE RHI...AUW
AND CWA. THE CHANCE FOR SHOWERS AND STORMS WITH SCATTERED MVFR
CIGS WILL INCREASE FRIDAY NIGHT AS A COLD FRONT DROPS
SOUTHEASTWARD OVER THE AREA.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM.....KURIMSKI
LONG TERM......MPC
AVIATION.......TDH



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.