000
FXUS63 KDLH 072002
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
302 PM CDT THU AUG 7 2008
.DISCUSSION...
EXTENSIVE CU FIELD ACROSS CWA AS WARMING OF BDRY LAYER HAS COMBINED
WITH SOME STEEPENING OF LAPSE RATES WITHIN THE 85/70H LAYER. VIS
IMAGERY SHOWS SOME INCREASING GROWTH TO CU OVER CTRL ONTARIO
ASSOCIATED WITH SOME FORM OF LINEAR LL BDRY. A FEW SHOWERS ARE
INDICATED ON XDR RADAR WITHIN THIS BAND.
AFTERNOON/OVERNIGHT...CUMULUS FIELD SHOULD DISSIPATE WITH LOSS OF
DIURNAL HEATING ALTHOUGH A FEW SHOWERS MAY TRY TO SNEAK INTO THE
ARROWHEAD OVER THE NEXT 4-6HRS. AFTERWARDS INCREASING ANTICYCLONIC
TRAJECTORY TO LOW/MID LVL FLOW SHOULD ALLOW FOR INCREASE
STRETCHING/DRYING OF AIR COLUMN.CLEARING SHOULD OCCUR OVERNIGHT WITH
DECOUPLED WINDS. COOL OVERNIGHT TEMPS EXPECTED ALTHOUGH DID NOT GO
AS LOW AS MAV AS UPSTREAM CONDITIONS/LAST NIGHTS NUMBERS DONT SEEM
TO LEND SUPPORT. MET VALUES SEEM MORE REASONABLE. PATCHY FOG LEFT IN
GRIDS/ZONES AS BUFKIT FOG PROFILES SHOW FAVORABLE HYDROLAPSE IN NEAR
SFC LAYER.
FRIDAY...AFTER EARLY FOG..EXPECT MORNING SUNSHINE WITH SOME
AFTERNOON CLOUDS. A BIT CONCERNED THAT AN AREA OF INSTABILITY
FORMING JUST NORTH OF INTERNATIONAL BORDER MAY GENERATE
AFTERNOON/EVENING RW/TRW. GFS SUGGESTS AN ELONGATED 85H THETAE AXIS
COMBINED WITH 85/70H LAPSE RATES EXCEEDING 7.5C/KM WILL FORM IN THIS
REGION. THIS AREA OF FORCING/INCREASED LOW/MID LVL RH IS FCST TO
SWING SOUTH ACROSS ERN CWA FRIDAY EVENING WITH TRACE AMOUNTS ALONG
NORTH SHORE.LATEST EC IS ALSO SUGGESTING THIS IDEA. WILL LET NEXT
SHIFT DECIDE IF WE NEED TO ADD SOME POPS/QPF IF ADDITIONAL GUIDANCE
KEEPS THIS TREND.
WEEKEND..MDLS HAVE BEEN POOR WITH CONSISTENCY AND CONSENSUS OVER THE
PAST FEW DAYS. HOWEVER A GENERAL AGREEMENT EXISTS THAT AN AREA OF
CONVECTION MAY DEVELOP FRIDAY EVENING OVER NRN PLAINS AND SLIDE
SOUTHEAST ALONG FAVORED THICKNESS CHANNEL INTO SRN MINNESOTA. HAVE
CUT BACK PREVIOUS POPS TO JUST THE SWRN EDGE OF THE CWA.SYSTEM WILL
EXIT MN EARLY SATURDAY AND IT APPEARS A DECENT WEEKEND IS ON TAP.
LAKE COOLING EXPECTED AS SIGNIFICANT SFC HIGH OVER ONTARIO GENERATES
A STIFF EASTERLY WIND INTO THE SHORE SAT AND SUNDAY.
&&
.AVIATION...
HIGH PRESSURE WILL DOMINATE THE WEATHER OVER THE REGION INTO FRIDAY
MORNING. THE CUMULUS DECK OVER THE REGION THIS AFTERNOON WILL
QUICKLY DISSIPATE THIS EVENING...LEAVING CLEAR TO SCATTERED CLOUDS.
PATCHY FOG WILL ONCE AGAIN BE POSSIBLE FOR A TIME LATE
TONIGHT...THROUGH ABOUT 9 AM.
&&
POINT TEMPS/POPS...
DLH 52 77 52 74 / 10 10 10 10
INL 46 77 50 79 / 10 10 10 10
BRD 49 81 55 81 / 10 10 20 10
HYR 46 80 48 79 / 10 10 10 10
ASX 47 75 49 74 / 10 10 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
CANNON/MELDE
