Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KDLH 291759 AAA
AFDDLH

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DULUTH MN
1259 PM CDT MON SEP 29 2014

.UPDATE...FOR 18Z AVIATION DISCUSSION BELOW...



&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 250 AM CDT MON SEP 29 2014

THE FA WAS LOCATED BETWEEN LOW PRESSURE OVER EASTERN LAKE SUPERIOR
AND HIGH PRESSURE OVER NW ONTARIO AT 07Z. THE COLD FRONT HAD EXITED
NW WI. A CHANNELED AREA OF VORTICITY WAS DRIFTING SWD FROM NORTHERN
MN BEING PUSHED ALONG BY A DIGGING UPPER LEVEL SHORTWAVE TROF. AN
AREA OF SHOWERS WAS MOVING THROUGH THE SOUTHERN MN ZONES AND ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. EXPECT THESE SHOWERS TO CONTINUE
TO PROGRESS SEWD THROUGH THE MORNING. SOME DRYING IS OCCURRING
BEHIND THE SHOWERS AS THE HIGH BEGINS TO PUSH INTO THE AREA. CLOUDS
WILL LINGER UNTIL MID AFTERNOON WHEN ENOUGH MIXING/DRYING ERODES
CLOUD COVER. NOT EXPECTING ANY SHOWERS OVER THE FA IN THE AFTERNOON
AND HAVE REMOVED THE MENTION. HAVE LOWERED WIND SPEEDS OVER INLAND
AREAS AS PRESSURE GRADIENT IS NOT THAT STRONG AND THERE IS ENOUGH OF
AN INVERSION TO PREVENT FULL MIXING.

UPPER LEVEL/SFC RIDGING COVER THE FA TONIGHT. EXPECTING A PARTLY
CLOUDY SKY AS COLUMN RH IS AROUND 50 PERCENT. WAA ALSO BEGINS IN THE
EVENING AND LASTS THROUGH THE NIGHT WHICH WILL KEEP THE MIN TEMPS
FROM DROPPING TOO LOW.

ON TUESDAY...THE RIDGING MOVES OVER LAKE SUPERIOR BY AFTERNOON. THE
WAA CONTINUES THROUGH THE DAY AHEAD OF A DEVELOPING AREA OF LOW
PRESSURE OVER THE NORTHERN PLAINS. MODEL DIFFERENCES IN THE
AFTERNOON WITH THE ONSET OF NEXT ROUND OF RAIN. HAVE GONE WITH A
CONSENSUS OF NO RAIN AND HAVE REMOVED. AN EASTERLY WIND OFF OF LAKE
SUPERIOR WILL KEEP MAX TEMPS IN THE UPPER 40S TO MIDDLE 50S NEAR THE
LAKE...AND UPPER 50S TO LOW 60S WELL INLAND.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 250 AM CDT MON SEP 29 2014

AN UPPER TROUGH OVER THE WESTERN CONUS/WESTERN CANADA WILL MOVE EAST
THROUGH THE PERIOD...ENDING UP OVER NEW ENGLAND BY LATE IN THE
PERIOD. A NORTHWEST FLOW WILL OCCUR OVER THE NORTHLAND BEHIND THIS
UPPER TROUGH. SEVERAL SHORTWAVES WILL IMPACT THE REGION THROUGH THE
EXTENDED PERIOD WITH CHANCES FOR SHOWERS AND PERHAPS A FEW
THUNDERSTORMS.

THE FIRST CHANCE FOR RAIN WILL OCCUR TUESDAY NIGHT AS A SHORTWAVE
AND SURFACE LOW MOVE NORTHEAST INTO MANITOBA BY 12Z WED. THE CHANCE
FOR RAIN WILL INCREASE WEDNESDAY...ESPECIALLY OVER EASTERN AREAS AS
ANOTHER WAVE MOVES THROUGH IN SOUTHWEST FLOW ALOFT AHEAD OF THE
TROUGH. A COLD FRONT WILL ALSO BE MOVING THROUGH THE AREA WEDNESDAY
NIGHT...KEEPING THE THREAT FOR SHOWERS OVER MUCH OF THE NORTHLAND
WITH CHANCES HIGHEST OVER EASTERN AREAS.

WE HAVE SOME POPS ON THURSDAY...BUT IF THE LATEST ECMWF/GFS REMAIN
CONSISTENT...MUCH OF THE DAY COULD END UP BEING DRY OR ONLY HAVE
LIMITED SHOWER COVERAGE AS THE AREA WILL BE BETWEEN SYSTEMS. A
STRONGER SHORTWAVE WILL THEN MOVE IN THURSDAY NIGHT WITH A CLOSED
UPPER LOW DEVELOPING OVER THE WESTERN GREAT LAKES ON FRIDAY. A
CHANCE FOR SHOWERS WILL OCCUR. 850MB TEMPS ARE FORECAST TO DROP TO
ZERO TO -4C BELOW BY 00Z SAT.

A WEAK SURFACE RIDGE WILL DEVELOP SATURDAY AND MOST AREAS WILL BE
DRY OR ONLY HAVE A SMALL CHANCE FOR RAIN.

HIGHS WILL BE IN THE SIXTIES FOR MOST AREAS ON WEDNESDAY AND
THURSDAY...BUT WILL DROP INTO THE FIFTIES BY FRIDAY...THEN TO THE
UPPER FORTIES TO LOWER FIFTIES SATURDAY. TEMPS WILL WARM A BIT INTO
SUNDAY AND BE MAINLY IN THE MID FIFTIES TO AROUND SIXTY. THERE WILL
ALSO BE A SLIGHT CHANCE FOR SHOWERS SUNDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT  1242 PM CDT MON SEP 29 2014

LARGE AREA OF LOW STRATUS LEFT IN WAKE OF RECENT FRONTAL PASSAGE. FAIRLY
STRONG SFC HIGH WILL BUILD INTO THE AREA NEXT 24 HRS. THE MAIN DIFFICULTY
IS DETERMINING HOW EXTENSIVE THE STRATUS WILL BE UNDER THE DEVELOPING
SUBSIDENCE INVERSION. SEVERAL OF THE CEILING FCST PRODUCTS FROM HI-
RES MDLS DEPICT RAPID CLEARING TREND LATER TODAY OVER MOST OF CWA
EXCEPT WISC ZONES. HOWEVER VIS SAT IMAGERY NOT IN AGREEMENT SO FAR
WITH A MUCH SLOWER TREND. WILL LEAN WITH A MORE PESSIMISTIC
FCST FOR NOW BASED ON FCST MDL SNDGS. LOCAL UPSLOPE FLOW FROM LAKE
SUPERIOR MAY ENHANCE LOWER CEILINGS OVERNIGHT NEAR KDLH.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  49  41  53  45 /   0  10  10  60
INL  51  36  59  46 /   0   0   0  60
BRD  55  39  59  52 /   0   0  10  60
HYR  51  37  62  49 /  30   0   0  50
ASX  49  39  56  46 /  10   0  10  30

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...BEACH HAZARDS STATEMENT UNTIL 8 PM CDT THIS EVENING FOR MNZ037.

WI...BEACH HAZARDS STATEMENT UNTIL 8 PM CDT THIS EVENING FOR WIZ001.

LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ121-
     140>148.

&&

$$

SHORT TERM...GSF
LONG TERM...MELDE
AVIATION...CANNON






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.