[LeArc] Forecast Discussion : MLI@ 10/7/02 3:00:29 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 070807
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
307 AM CDT MON OCT 7 2002

HIGH PRESSURE CENTERED OVER NORTHEAST KANSAS AT 07Z WITH RIDGE
EXTENDING NORTH THROUGH WESTERN IOWA AND CENTRAL MINNESOTA.  TEMPS
NEAR THE RIDGE AXIS IN NW IA AND SW MN IN THE UPPER 20S/LOWER 30S.
TO THE EAST...NEAR MS RIVER...LINGER SC DECK HOLDING TEMPS IN THE LOW
40S.  LAST COUPLE OF IR IMAGES SHOWS NUMEROUS HOLES APPEARING IN CLOUD
DECK AND BACK EDGE NEAR CWA'S WESTERN BORDER.  WE SHOULD GET AT LEAST
A COUPLE OF HOURS OF GOOD RADIATIONAL COOLING THIS MORNING...ALLOWING
TEMPS TO DIP INTO THE LOW 30S...ESPECIALLY IN THE NW.

07/00Z UA ANALYSIS SHOWS MID LEVEL TROUGH OVER NORTH CENTRAL U.S.
H3 JET EXTENDED FROM NERN MO THROUGH THE EASTERN GREAT LAKES.   S/W
RIDGING NOTED OVER MT/WRN CANADA AHEAD OF NEXT S/W JUST ENTERING NWRN
B.C.  MODELS IN GOOD AGREEMENT WITH MID LEVEL FLOW THE NEXT COUPLE OF
DAYS.  S/W TROUGH OVER NORTH CENTRAL STATES...LIFTS RAPIDLY NORTHEAST
TODAY.  BY TUESDAY S/W MOVES OUT OF NW CANADA INTO ERN MT/NORTH DAKOTA.
THIS SYSTEM WILL BRING THE NEXT THREAT OF RAIN TO THE REGION AS IT
MOVES ACROSS MN TUESDAY NIGHT.

IN THE NEAR TERM DEPARTING HIGH PRESSURE AND CLOUD TRENDS WILL CREATE
SOME PROBLEMS WITH TEMPS TODAY.  SURFACE RIDGE SHOULD BE OVER MS RIVER
BY 12Z AND THEN SHIFTS EAST INTO MICHIGAN BY 00Z. TYPICALLY...TEMPS
HAVE A DIFFICULT TIME WARMING MUCH...IN LIGHT SOUTHEAST FLOW OFF
DEPARTING HIGHS.  ALSO COMPOUNDING PROBLEMS WITH TEMP FORECAST TODAY
WILL BE THE MID/HI WAA CLOUDS MOVING OUT OF THE NORTHERN PLAINS.
EXPECT SOME OF THE CLOUDS TO MOVE ACROSS NRN CWA LATE THIS
MORNING/THIS AFTERNOON. WILL FAVOR THE COOLER MAV TEMPS FOR TODAY...AND
MAY EVEN GO A BIT COOLER NORTH WITH EXPECTED CLOUD COVER.  SOUTHWEST
LOW LEVEL FLOW AND SOME CLOUDS OVERNIGHT WILL KEEP TMPS IN THE UPPER 30S
TO LOWER 40S TONIGHT.  TEMPS WILL PROBABLY FALL THE MOST THIS EVENING...
THEN STEADY OUT AS SOUTHWEST FLOW INCREASES.  S/W MOVING OUT OF THE
NORTHERN PLAINS TUESDAY WILL BRING A CHANCE OF SHOWERS TO THE REGION.
SURFACE LOW TRACKS ACROSS SRN/CENTRAL MN...DRAGGING COLD FRONT THROUGH
EASTERN IA/NW IL TUESDAY AFTERNOON/EVENING.  LOOKS LIKE MOISTURE WILL BE
LIMITED...SO BULK OF PCPN SHOULD STAY NEAR AND NORTH OF THE SURFACE LOW
TRACK.  CURRENT FORECAST HAS THIS HANDLED WELL WITH HIGHER CHANCE POPS
NORTH.  SPC HAS GENERAL THUNDER OUTLOOKED FOR REGION TUESDAY.   IT LOOKS
LIKE THE BEST FORCING AND MID LEVEL LAPSE RATES WILL STAY NORTH OF
CWA...SO WILL CONTINUE WITH SHOWER WORDING FOR NOW.  GRADIENT AHEAD OF
FRONT IS NOT VERY IMPRESSIVE TUESDAY...SO MIXING SHOULD BE HELD TO A
MINIMUM WITH WEAK SW FLOW AND CLOUDS.  WILL GO WITH A BLEND OF COOLER
MAV/FWC NUMBERS.  WEDNESDAY THROUGH THURSDAY DRY WX  AND NEAR/SIGHTLY
BELOW NORMAL TEMPS SHOULD DOMINATE WX ACROSS CWA.

00Z AVN/MRF RUNS PAINT AN INTERESTING PICTURE FOR THE WEEKEND...
DEVELOPING A DEEP SFC LOW OVER NM LATE SATURDAY AND LIFTING IN
NORTHEAST THROUGH WESTERN IA/MN LATE SUNDAY.  UKMET IS TRENDING TOWARD
THIS SOLUTION ON ITS 07/00Z RUN...HOWEVER THE AVN/MRF IS MUCH DEEPER
WITH THE S/W DIGGING INTO THE WESTERN U.S. AND THE RESULTING SURFACE
LOW.  NO CHANGES ARE PLANNED FOR THE EXTENDED WITH DIFFERING MODEL
SOLUTIONS...BUT DAY SHIFT WILL HAVE TO RE-EVALUATE.


.DVN...
IA...NONE.
IL...NONE.
MO...NONE.

DLF