[LeArc] Forecast Discussion : MLI@ 5/11/2003 3:30:51 PM

[learc@mailman.qth.net]

The following weather message is provided by McDonough County E.S.D.A.


FXUS63 KDVN 112028
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
320 PM CDT SUN MAY 11 2003

GO AWAY CYCLONE...YA BOTHA' ME! SHORT RANGE MODELS SIMILAR IN
MIGRATING DEEP...VERTICALLY STACKED VORTEX SLOWLY EAST ACRS THE GRT
LKS THROUGH MONDAY NIGHT. UPPER RIDGING TO FOLLOW FOR TRANQUIL FIRST
PART OF THE WEEK AFTER A VERY BLUSTERY MOTHERS DAY. INTENSE SFC LOW
OVER GREEN BAY STARTING TO GYRATE EAST-SOUTHEAST TOWARD DEEP
PRESSURE FALL BULLSEYE OVER WEST CENTRAL LOWER MI. RUC AND META
PICKING UP ON THIS AND PROPAGATE LOW TO THE EAST OVER NORTHERN
LOWER MI. EXTRAPOLATION AND SPEED OF SFC SYSTEM...PLUS UPSTREAM WIND
REPORTS/SFC OBS SUGGESTS WIND ADVISORY NEEDS TO BE EXTENDED ACRS AT
LEAST THE NORTHEAST THIRD OF THE CWA UNTIL 02Z.

LARGE STRATOCU DECK CONTINUES TO ROTATE AROUND LOW PRESSURE FEATURE
...BUT SHORT RANGE MODEL LMRH PROGS SUGGEST CLEAR OUT FROM WEST-
SOUTHWEST...TO THE NORTHEAST AS NIGHT PROGRESSES. THIS TO HAVE IMPACT
ON POTENTIAL LOW TEMPS...AND LIKE PREVIOUS SHIFT MAY PLAY MORE
PESSIMISTIC WITH CLEAR OUT. LONG FETCH TRAJECTORIES FROM EASTERN ND
SOURCE REGION SUGGESTS TEMPS MAY DIP INTO THE MID TO UPPER 30S LATE
TONIGHT WITH CLEAR OUT ACRS THE NORTHWEST. BUT WIND MIXING MODERATING
FACTOR WILL KEEP NORTHWEST CORNER FROM DIPPING LOWER THAN UPPER 30S.
REST OF THE CWA TO GENERALLY RANGE FROM 40 TO 45...STILL SEASONABLY
COOL.

LINGERING LLVL CYCLONIC GRADIENT AND STEEP 1000-H85 MB LAPSE RATES
BUILDING TO OVER 9 C/KM BY MIDDAY MONDAY...TO MAKE FOR OPTIMUM MIXING
AND ANOTHER WINDY DAY. NOT ADVISORY CRITERIA THOUGH. FEEL ENOUGH LLVL
MOISTURE FOR ABOVE PARAMETERS TO BE A CU FACTORY MONDAY...MUCH LIKE
WHAT'S GOING ON ACRS EAST NE AND EAST SD THIS AFTERNOON. THUS WILL
WORD PARTLY CLOUDY. RIDGE CENTER TO SETTLE OVER THE AREA ON MONDAY
NIGHT...WITH LIGHT WINDS AND CLEAR SKIES MAKING FOR COOLEST NIGHT
OF CURRENT INCOMING COLD FETCH REGIME. 2ND NIGHT OF COLD FRONT
RULE/COLDEST NIGHT AND EXTENT OF INCOMING CANADIAN AIR SUGGESTS MUCH
OF CWA TO DIP INTO THE 30S BY TUESDAY MORNING...WITH MID 30S POSSIBLE
ACRS THE NORTH. INCOMING SYSTEM IN NORTHERN STREAM TO BRING NEXT
PRECIP CHANCE BY LATE TUE NIGHT ACRS THE WEST.

LONGER RANGE(WED-SUN)...MEDIUM RANGE MODELS HAVE THEIR DIFFERENCES...
BUT NOW LATEST UKMET AND ECMWF SIDING MORE WITH MRF IN TRYING
TO PHASE NORTHERN AND SOUTHERN STREAM WAVE ENERGY ACRS THE UPPER
MIDWEST ON WED. ENSEMBLE GENERALLY SUGGESTS NORTHERN STREAM WAVE TO
DROP DOWN ACRS THE AREA FOR PRECIP THREAT ON WED...AND AS WAVE DROPS
DOWN ACRS THE OH RVR VALLEY AND DEEPENS...RAIN THREAT MAY LINGER INTO
THU...ESPECIALLY ACRS THE SOUTHEAST. CLOUD COVER AND PRECIP...AS WELL
PROJECTED LLVL THERMAL PARAMETERS SUGGEST HIGHS ONLY IN LOW TO MID
60S FOR WED AND THU...WITH SOME UPPER 50S POSSIBLE ON THU. WILL
FOLLOW EURO AND UKMET'S SUGGESTED SCENARIO OF COOL GRT LKS RIDGING TO
END THE WEEK BEHIND EXITING UPPER LOW. WILL BANK ON THIS RIDGING TO
HOLD OFF NEXT WAVE OF PACIFIC ENERGY AND PRECIP THREAT UNTIL SUNDAY.

COORDINATED WITH DMX...THANX!


DVN...
IA...WIND ADVISORY EXTENSION UNTIL 9 PM NORTHEAST OF AN INDEPENDENCE
...TO A DAVENPORT LINE.
IL...WIND ADVISORY EXTENSION UNTIL 9 PM ALONG AND NORTH OF I-80.
MO...NONE.

$$

JDH