Area Forecast Discussion
Issued by NWS Green Bay, WI

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000
FXUS63 KGRB 261654
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1154 AM CDT SAT JUL 26 2014

UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE

.UPDATE...
ISSUED AT 508 AM CDT SAT JUL 26 2014

MID LEVEL DRYING EVIDENT WITH THE WATER VAPOR LOOP WAS AIDING WITH
LOWERING WET BULBS ACROSS NORTHEAST WISCONSIN EARLY THIS MORNING.
COMBINED WITH SOME MID LEVEL INSTABILITY WITH THE SHORT
WAVE...ISOLATED STORMS WERE PRODUCING UP TO NICKEL SIZE HAIL OVER
FOREST AND MARINETTE COUNTIES. STORMS WERE PULSING AND WILL
CONTINUE TO BE MONITORED FOR A POSSIBLE WARNING THIS MORNING...BUT
SO FAR HAVE NOT EXCEEDED THE STORM WHICH PASSED NEAR LAONA WHICH
PRODUCE NICKEL SIZE HAIL.
&&

.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 333 AM CDT SAT JUL 26 2014

EARLY THIS MORNING...AREA RADARS AN OBSERVATIONS SHOW ISOLATED
TO SCATTERED SHOWERS WITH AN ISOLATED THUNDERSTORM PASSING OVER
NORTHERN WISCONSIN. CONVECTION ASSOCIATED WITH A  SHORT WAVE
PASSING OVER THE NORTHERN GREAT LAKE REGION IN THE LFQ REGION OF
THE UPPER JET AND AHEAD OF A WEAK FRONTAL SYSTEM TRACKING OVER THE
STATE. IN ADDITION MU CAPES NEAR 400 IN THE 800 TO 700 MB LEVEL
WERE AIDING WITH MORE STORMS ACROSS THE NORTH CENTRAL WISCONSIN
EARLY THIS MORNING. TIMING OF THIS FRONTAL SYSTEM AND UPPER JET
DYNAMICS MAY SUGGEST KEEPING AN ISOLATED MENTION OF SHOWERS/STORMS
IN THE MORNING HOURS OVER EASTERN WISCONSIN. THESE DYNAMICS WERE
RUNNING A TAD SLOWER THAN PROGS 24 HOURS AGO.

OTHERWISE ANTICIPATE A DRY PERIOD LATER TODAY AS THE UPPER JET
SUPPORT LESSONS...THE FRONTAL BOUNDARY SHIFTS EAST AND WEAK
RIDGING AHEAD OF THE APPROACHING UPPER LOW FROM SOUTHERN CANADA.
A FEW MODELS LINGER SPOTTY CONVECTION OVER LAKE MICHIGAN AND DOOR
COUNTY INTO THE EARLY AFTERNOON HOURS...SO WILL CONSIDER LONGER
DURATION MINOR POPS IN THIS REGION TODAY. FORECAST SOUNDINGS FOR
EACH THE NAM AND GFS GENERATE SOME HEALTHY CAPES THIS AFTERNOON
OVER MUCH OF THE FORECAST AREA...BUT NO TRIGGER...UNLESS THE
FRONTAL BOUNDARY HANGS AROUND THIS AFTERNOON OVER EASTERN AREAS...SO
SOME CONCERN WITH GOING WITH A DRY FORECAST.

PLENTY OF CLOUDS NEAR AND AHEAD OF THIS SURFACE FRONTAL BOUNDARY
BUT WITH THE WARM START THIS MORNING AND DECREASING CLOUDS LATER
TODAY...WILL NOT ADJUST TEMPS MUCH...PERHAPS A FEW DEGREES COOLER
DUE TO LINGERING CLOUDS WITH THE SLOWER SURFACE BOUNDARY.

FOCUS THEN TURNS TO THE UPPER LOW SYSTEM TO DROP OVER THE REGION
TONIGHT INTO SUNDAY. ANTICIPATE SHOWERS WITH ISOLATED STORMS TO BE
ON THE INCREASE FROM NORTHWEST TO SOUTHEAST TONIGHT AND THEN
WIDESPREAD FOR SUNDAY. HOPEFULLY THE REGION WILL GET SOME MUCH
NEEDED RAIN WITH THIS SYSTEM. MAX TEMPS FOR SUNDAY LIKELY TO OCCUR
AROUND NOON BEFORE BECOMING STEADY WITH RAIN AND CAA PATTERN
DEVELOPING. TOTAL TOTALS IN THE LOWER 50S AND WEB BULB TEMPS
FALLING TO AROUND 8500 SUNDAY AFTERNOON PROVIDES SOME POTENTIAL OF
HAIL WITH ANY OF THE STORMS.

.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 333 AM CDT SAT JUL 26 2014

MODELS WERE IN GOOD AGREEMENT...SHOWING A CLOSED 500MB LOW OVER
QUEBEC WITH A TROUGH OVER THE EASTERN 2/3RDS OF THE CONUS. THIS
PATTERN IS NOT EXPECTED TO CHANGE MUCH DURING THE UPCOMING WEEK.
TIMING OF SHORT WAVES IN NORTHWEST FLOW ALOFT WILL BE A CHALLENGE
AS THESE FEATURES WILL BRING CHANCES FOR RAIN. SOME SHOWERS AND
STORMS ARE POSSIBLE IN INSTABILITY AROUND OR AFTER PEAK DAYTIME
HEATING. POPS ARE IN THE SLIGHT CHANCE OR LOW END CHANCE
CATEGORIES FOR MOST OF THE LONG TERM. HIGH TEMPERATURES SHOULD BE
NEAR OR SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR WITH CLOUDS
AND STORMS.
&&

.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1153 AM CDT SAT JUL 26 2014

DRIER AIR IS GRADUALLY MOVING ACROSS NORTH-CENTRAL AND
NORTHEAST WISCONSIN FROM THE NORTHWEST LATE THIS MORNING.  CLOUDS HAVE BEEN
DISSIPATING THIS MORNING OVER N-C WISCONSIN WITH THE ARRIVAL OF THIS
DRIER AIR...AND THIS TREND SHOULD MOVE INTO NORTHEAST WISCONSIN BY
EARLY THIS AFTERNOON.  THEN ONCE CIGS LIFT AND SCATTER...VFR
CONDITIONS WILL REMAIN PRESENT THROUGH THE EVENING.  AFTERWARDS...AN
UPPER LEVEL LOW WILL DROP SOUTHEAST INTO NORTHERN WISCONSIN
OVERNIGHT INTO SUNDAY MORNING.  SPOTTY SHOWERS AND A FEW
THUNDERSTORMS ARE POSSIBLE AHEAD OF THIS SYSTEM OVERNIGHT...THEN
WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS ARE LIKELY TO DEVELOP
SUNDAY MORNING ALONG WITH LOWERING CIGS.
&&

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

$$

UPDATE.........TDH
SHORT TERM.....TDH
LONG TERM......MG
AVIATION.......MPC





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