FXUS63 KDLH 030930
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
330 AM CST THU DEC 3 2009
.DISCUSSION...
LES ALONG SOUTH SHORE HAS GRADUALLY SHIFTED EWRD FROM
DOUGLAS/BAYFIELD COUNTIES INTO ASHLAND COUNTY EARLY THIS MORNING AS
WINDS BACK. EXPECT THIS TREND TO CONTINUE THIS MORNING. WL CONTINUE
LES ADVISORY FOR MORE ACCUMULATING SNOW IN ASHLAND AND IRON
COUNTIES. REPORTS SLIM ATTM...BUT EARLIER REPORT OF HALF INCH AT
GILE. WEB CAM AT HURLEY APPEARS TO BE AN INCH OR SO OF NEW SNOW.
ASX AWOS REPORT LIGHT SNOW WITH VSBY AS LOW AS 3/4SM. WITH A GOOD FETCH...
ABOUT A -10 TO -12 DEGREE DELTA T BETWEEN LAKE AND 850 MB
INCREASING SHEAR AND RISING INVERSION HGTS...LES WILL GET
ORGANIZED THIS MORNING AND CONTINUE THROUGH THE DAY. WILL STAY
WITH THE 4-7" AMOUNTS.
ELSEWHERE- LITTLE CHANGE IN THE PATTERN WITH UPPER LOW/CYCLONIC
FLOW OVR THE REGION BRINGING WAVES THROUGH. TIMING DIFFICULT AND
LIKE THE BROADBRUSH SNOWSHOWER TECHNIQUE THROUGH FRIDAY.
IN PAST 2 HOURS MORE ECHOES SHOWING UP ON RADAR FROM IRON RANGE AND
SOUTH...IN RESPONSE TO NEXT WAVE COMING SOUTH OUT OF CANADA.
NO CHANGE TO TEMPS...MORE SEASONABLE WITH DAYTIME HIGHS IN
20S...LOWS IN THE TEENS.
.EXTENDED...FRIDAY NIGHT THROUGH WEDNESDAY
MODELS ARE IN OK AGREEMENT EARLY...THEN DIVERGE SIGNIFICANTLY BEYOND
THE FIRST 24 HOURS OF THE EXTENDED PERIOD. THE DIFFERENCES ARISE IN
HOW THE GFS/ECMWF HANDLE THE SHORTWAVE/UPPER LOW THAT DROPS SOUTH TO
SOUTHWEST THROUGH ONTARIO. THE ECMWF WEAKENS THIS FEATURE...AND
MOVES IT EAST ON SUNDAY...WHERE THE GFS DROPS IT FURTHER WEST AND
KEEPS THE CLOSED LOW OVER THE DAKOTAS. WE DID NOT MAKE TOO MANY
CHANGES TO THE EXTENDED...BUT DID ADJUST/ADD SOME POPS FROM FRIDAY
NIGHT THROUGH SUNDAY. WE ADDED SOME POPS TO THE NORTH SHORE...DOWN
INTO THE TWIN PORTS ON SATURDAY WITH BOTH MODELS SHOWING WEAK
ONSHORE WINDS IN THESE AREAS. WE ALSO ADDED SOME POPS TO THE SOUTH
SHORE SATURDAY NIGHT INTO SUNDAY FOR SOME LES. OVERALL...WE LEANED
TOWARD THE ECMWF EARLY IN THE PERIOD. THE GFS ENSEMBLE MEAN WAS DID
NOT SHOW REAL GOOD AGREEMENT WITH THE OPERATIONAL RUN. CHANGES
BEYOND SUNDAY WERE VERY SMALL OR NIL DUE TO TOO MUCH MODEL
UNCERTAINTY.
.AVIATION...06Z TAF ISSUANCE
MAINLY MVFR CONDITIONS ARE EXPECTED DURING THE DURATION OF THE TAF
CYCLE. SOME LOCALIZED IFR CIGS WILL BE POSSIBLE...ESPECIALLY
DURING THE NIGHT AND EARLY ON THURSDAY. A FEW HOLES IN THE CLOUDS
MAY DEVELOP ON THURSDAY...BUT THE MAJORITY OF THE REGION SHOULD
MAINTAIN AN MVFR CLOUD DECK.
&&
.POINT TEMPS/POPS...
DLH 23 12 24 16 / 20 20 30 20
INL 20 12 23 10 / 20 40 30 10
BRD 25 12 22 15 / 20 20 20 10
HYR 25 14 23 15 / 20 20 20 10
ASX 26 18 26 17 / 40 20 30 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...LAKE EFFECT SNOW ADVISORY UNTIL 10 PM CST THIS EVENING FOR
WIZ003-004.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CST SATURDAY FOR LSZ146-147.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR LSZ121-148.
&&
$$
CLC/MELDE