Tuesday, March 30, 2010

Area Forecast Discussion - South Central/Southwest Missouri

FXUS63 KSGF 301855
NATIONAL WEATHER SERVICE SPRINGFIELD MO
155 PM CDT TUE MAR 30 2010

..LONG TERM DISCUSSION UPDATE...

UPDATE...

NUDGED UP HIGHS FOR TODAY BASED ON SHORT TERM TEMPERATURE TRENDS
AND MORNING RAOB. DESPITE FILTERED SUNSHINE FROM HIGH
CLOUDS...TEMPERATURES ARE HAVING LITTLE PROBLEM CLIMBING GIVEN THE
DRY AIRMASS. HAVE ALSO LOWERED HOURLY DEW POINT AND RELATIVE
HUMIDITY GRIDS AS AREA SOUNDINGS...KSGF...KOUN...KTOP...KSHV...ALL
INDICATE QUITE A DRY LAYER JUST OFF THE DECK. THIS WILL HAVE BIG
IMPACTS ON FIRE WEATHER. SEE DISCUSSION BELOW. FINALLY...HAVE
INCREASED WINDS ABOUT 5 MPH ACROSS MUCH OF THE AREA.

SCHAUMANN

&&

LONG TERM (FRIDAY - TUESDAY)...
AN UPPER LEVEL DISTURBANCE AND ASSOCIATED COLD FRONT WILL BE
APPROACHING THE REGION BY FRIDAY. THERE WERE SOME MINOR TIMING
DIFFERENCES BETWEEN THE GFS AND THE SLOWER ECMWF...AND HAVE LEANED
OUR FORECAST CLOSER TO THE ECWMF. THEREFORE SHOWERS AND MAYBE EVEN
SOME THUNDERSTORMS WILL APPROACH SOUTHWEST MISSOURI FRIDAY
EVENING...SLOWLY TRANSLATING ACROSS THE REST OF THE OZARKS FRIDAY
NIGHT AND EVEN INTO SATURDAY. GIVEN THE LACK OF QUALITY GULF
MOISTURE...INSTABILITY LEVELS WILL BE VERY MODEST...WITH MODELS
PRELIMINARILY ONLY SHOWING LESS THAN 500 J/KG OF MOST UNSTABLE
CAPE. THEREFORE SEVERE THUNDERSTORMS FRIDAY NIGHT AND SATURDAY ARE
NOT EXPECTED AT THIS TIME.

A BRIEF PERIOD OF DRY WEATHER IS EXPECTED FOR SATURDAY NIGHT THROUGH
MONDAY AFTERNOON...WHICH WILL BE FOLLOWED BY ANOTHER FRONTAL PASSAGE
MONDAY NIGHT INTO TUESDAY. DESPITE THE LACK OF MOISTURE
RETURN...MODELS DEVELOP QPF ACROSS THE ENTIRE SOUTHERN MISSOURI
REGION. HAVE PLACED A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
GRIDS DURING THIS PERIOD.

REGARDING TEMPERATURES THROUGH THE EXTENDED...THESE PREVIOUSLY
MENTIONED FRONTAL PASSAGES WILL BE OF PACIFIC ORIGIN. THEREFORE
TEMPERATURES WILL REMAIN MILD THROUGH THE ENTIRE EXTENDED
PERIODS...WITH HIGHS RANGING FROM THE 60S AND 70S...AND LOWS IN THE
40S AND 50S ON A NIGHTLY BASIS.

CRAMER

&&

AVIATION...

PILOTS FLYING IN AND OUT OF THE SOUTHWEST MISSOURI AIRPORTS WILL
NEED TO MONITOR FOR LOW LEVEL WIND SHEAR OVER THE NEXT 24 HOURS.
PARTICULARLY TONIGHT...A 45 - 55 KNOT LOW LEVEL JET WILL ASSUME A
POSITION DIRECTLY OVER SOUTHWEST MISSOURI. SURFACE WINDS WILL ALSO
BE GUSTY...WITH SOME GUSTS IN EXCESS OF 25 KNOTS AT TIMES.

LOW PRESSURE DEVELOPING ACROSS THE PLAINS IS THE MAIN REASON FOR THE
INCREASING WINDS. MEANWHILE...NO LOW CEILINGS OR OBSTRUCTIONS TO
VISIBILITIES ARE EXPECTED OVER THE NEXT 24 HOURS.

CRAMER

&&

FIRE WEATHER...

HOISTED A RED FLAG WARNING FOR THIS AFTERNOON FOR AREAS ALONG AND
WEST OF THE HIGHWAY 65 CORRIDOR. DRIER AIR IS BEGINNING TO MIX
DOWN TO THE SURFACE...RESULTING IN RELATIVE HUMIDITIES ALREADY IN
THE UPPER 20 PERCENT RANGE AT THE NOON HOUR. SUSTAINED WINDS IN
THE 15 TO 25 MPH RANGE CONTINUE...WITH GUSTS OVER 35 MPH. WILL BE
LOOKING CLOSELY AT WEDNESDAY FOR POSSIBLE EXPANSION/UPGRADE OF
CURRENT FIRE WEATHER WATCH.

SCHAUMANN

&&

SGF WATCHES/WARNINGS/ADVISORIES...
MO...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR MOZ055-066>068-
077>079-088>090-093>095-101>103.

FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR MOZ066-067-077-078-088-089-093-094.

KS...RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR KSZ073-097-101.

FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR KSZ073-097-101.

&&

$$

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