230
FXUS63 KGRB 131145
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
645 AM CDT TUE AUG 13 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 347 AM CDT TUE AUG 13 2013
MINOR PCPN THREAT TODAY AND COOL TEMPERATURES ARE THE MAIN FCST CONCERNS.
WV IMAGERY SHOWED A COUPLE S/W TROFS HEADED TOWARD NORTHERN WI...ONE
CROSSING WSTRN LK SUP...AND ANOTHER NEAR LK WINNIPEG. HAVE KEPT A
SLIGHT CHANCE OF SHOWERS ACROSS NORTH CENTRAL AND FAR NE WI
THROUGH MIDDAY TO ACCOUNT FOR THESE FEATURES. PCPN CHANCES APPEAR
NIL TONIGHT INTO WEDNESDAY...AS DRY CANADIAN HIGH PRESSURE SETTLES
OVER THE REGION. ADDED SOME PATCHY FOG LATE TONIGHT...AS SFC AND
BOUNDARY LAYER WINDS BECOME LIGHT.
RAOBS AND FCST SOUNDINGS SUGGEST MIXING THROUGH 825-800 MB THE NEXT
COUPLE DAYS. THIS SUPPORTS HIGHS IN THE MID 60S TO LOWER 70S TODAY...
AND LOWER TO MIDDLE 70S ON WEDNESDAY. EXPECT THE TYPICAL COLD
SPOTS TO DROP INTO THE UPPER 30S AND LOWER 40S TONIGHT...WHILE
MOST OTHER LOCATIONS SETTLE INTO THE MID TO UPPER 40S.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 347 AM CDT TUE AUG 13 2013
THE LATEST GFS ENSEMBLE MEAN INDICATES THAT THE OVERALL PATTERN WILL
DEAMPLIFY THROUGH EARLY NEXT WEEK...AS THE BEEFY WESTERN CANADA
RIDGE BREAKS DOWN AND MOVES EAST. VERY FEW CHANCES OF PRECIP OVER
THE PERIOD. HAVE BEEN MONITORING WEAK SHORTWAVE ENERGY ARRIVING
THIS WEEKEND OVER THE PAST SEVERAL MODEL RUNS...BUT LATEST TRENDS
ARE SHIFTING IT INTO THE MID-MISSISSIPPI VALLEY REGION. WITH THE
QUIET WEATHER EXPECTED...AN ECMWF/GFS BLEND SHOULD SUFFICE.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...SURFACE HIGH PRESSURE WILL
BE SHIFTING SOUTH TOWARDS THE OHIO VALLEY AND THEN TO THE EAST COAST
OVER THIS PERIOD. SHORTWAVE ENERGY WILL BE DIVING SE INTO THE
CENTRAL PLAINS/MID-MISSISSIPPI VALLEY AT THE SAME TIME. THIS SYSTEM
LOOKS TO BE TOO FAR SW FOR MUCH IMPACT ON THE REGION. PERHAPS SOME
HIGH CLOUDS COULD ARRIVE THURSDAY NIGHT BUT OTHERWISE...PLENTY OF
DRY AIR ALOFT WILL LEAD TO CLEAR TO MOSTLY CLEAR CONDITIONS. HIGHS
ON THURSDAY SHOULD REACH THE MID TO UPPER 70S AND WILL RAISE HIGHS A
DEGREE OR TWO. LOWS IN THE 40S AND 50S WEDNESDAY NIGHT WILL WARM
INTO THE 50S EVERYWHERE THURSDAY NIGHT.
REST OF THE FORECAST...HIGH PRESSURE WILL BE CENTERED OVER NEW
ENGLAND FRIDAY THROUGH THE WEEKEND...AND A SURFACE RIDGE AXIS WILL
EXTEND TO THE WESTERN GREAT LAKES. LIGHT SOUTHWEST WINDS WILL
GRADUALLY DRAW IN WARMER AND MORE MOIST AIR. THE TROUGH MOVING
ACROSS THE CENTRAL PLAINS EARLIER IN THE WEEK WILL MOVE VERY LITTLE
OVER THE CENTRAL MISSISSIPPI VALLEY. TEMPS IN THE UPPER 70S TO LOW
80S. THE NEXT SHORTWAVE WILL MOVE TOWARDS THE REGION ON MONDAY AND
WILL BRING THE NEXT CHANCE OF PRECIP.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 637 AM CDT TUE AUG 13 2013
AN UPPER LEVEL DISTURBANCE WILL BRUSH THROUGH FAR NE WI THIS
MORNING...AND BRING A BAND OF CLOUDS THROUGH THE FORECAST AREA.
A FEW SHOWERS MAY BRUSH THROUGH NC/FAR NE WI...BUT CONFIDENCE
IS NOT HIGH ENOUGH TO ADD TO THE RHI TAF. THE CLOUDS SHOULD
SCATTER OUT BY EARLY AFTERNOON AS THE UPPER DISTURBANCE SHIFTS
EAST. HIGH PRESSURE WILL BRING LIGHT WINDS TONIGHT...AND SET
THE STAGE FOR SOME PATCHY FOG DEVELOPMENT...ESPECIALLY IN THE
WISCONSIN RIVER VALLEY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....KIECKBUSCH
LONG TERM......MPC
AVIATION.......KIECKBUSCH