Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 201738
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1238 PM CDT SAT SEP 20 2014

.UPDATE...
ISSUED AT 1155 AM CDT SAT SEP 20 2014

THE FORECAST IS MOSTLY ON TRACK LATE THIS MORNING AS A RATHER
STRONG WAVE IN NW FLOW CONTINUES TO RAPIDLY APPROACH THE NORTHLAND
FROM MANITOBA/SASKATCHEWAN/N DAKOTA. WE ARE CURRENTLY STILL UNDER
THE INFLUENCE OF LARGE SCALE SUBSIDENCE BEHIND DEPARTING WAVE THAT
PASSED OVER THE REGION OVERNIGHT..BUT LOBE OF FORCING FOR ASCENT
OVER ERN N DAKOTA IS RAPIDLY MOVING TOWARD NRN MN. LINEAR
EXTRAPOLATION BRINGS LINE OF SHOWERS/TSTORMS TO OUR WRN CWA BORDER
REGION BETWEEN 2 AND 3 PM..AND WE HAVE MADE SOME SLIGHT
ADJUSTMENTS TO POPS AND WEATHER BASED ON THESE OBSERVATIONAL
TRENDS.

LARGE SCALE KINEMATICS FOR SEVERE STORMS WILL BE OVERALL WEAKER
THAN YESTERDAY OVER NRN/NW MN..BUT SUFFICIENT CAPE/SHEAR SHOULD
STILL BE IN PLACE BY MID-LATE AFTERNOON TO SUPPORT A FEW SEVERE
STORMS. GIVEN THE STRONG FLOW AT 850/700 MB..THE PRIMARY THREAT
MAY END UP BEING WIND..WITH A SECONDARY HAIL THREAT AS TEMPS ALOFT
COOL. OVERALL CHANGES TO THE FORECAST WERE MINOR.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 345 AM CDT SAT SEP 20 2014

AT 345 AM...THE STRONG THUNDERSTORM THAT HAD MOVED ACROSS THE
INTERNATIONAL BORDER REGION HAD LARGELY DISSIPATED AS IT MOVED
INTO MORE STABLE AIR OVER THE EASTERN PORTION OF THE CWA. ISOLATED
SHOWERS CONTINUED TO PERCOLATE OVER THE ARROWHEAD AND JUST EAST OF
KINL. AREAS OF FOG CONTINUED TO PLAGUE THE EASTERN 2/3 OF THE
CWA...ESPECIALLY NEAR LAKE SUPERIOR WHERE THERE WAS SOME LOCAL
DENSE FOG AT KDLH. TEMPERATURES WERE LARGELY IN THE 60S.

THE MAIN FOCUS FOR TODAY WILL BE RESOLVING VARIOUS MODEL
DIFFERENCES IN TERMS OF PRECIPITATION COVERAGE AND TIMING OF THE
STRONG/SEVERE STORMS LATER TODAY. FOR THIS MORNING...HAVE
GENERALLY CONFINED ANY CHANCE OF SHOWERS/STORMS TO THE NORTH AND
EAST. AREAS OF FOG SHOULD PERSIST FOR A TIME THIS MORNING BEFORE
IMPROVING AS WESTERLY WINDS INCREASE AND BRING SOMEWHAT DRIER AIR
INTO THE AREA. HAVE TRIED TO DEFINE THE GREATEST THREAT OF
PRECIPITATION IN HOURLY POPS/WX. OVERALL IT SHOULD BE A GENERALLY
DECENT DAY FOR MUCH OF THE AREA AND MUCH OF THE TIME WITH FAIRLY
SMALL CHANCES OF PRECIPITATION.

WHILE MUCH OF TODAY WILL LIKELY TURN OUT TO BE PRETTY DECENT...IT
IS LOOKING INCREASINGLY LIKELY THAT A LINEAR MCS WILL DEVELOP IN
THE RED RIVER VALLEY THIS AFTERNOON...AND SPREAD INTO THE WESTERN
CWA LATER IN THE DAY AND TO THE TWIN PORTS BY LATE AFTERNOON/EARLY
EVENING. THE HIGH RESOLUTION MODELS AS WELL AS THE NAM/ECMWF AND
GFS ALL SUPPORT THE DEVELOPMENT OF A LINE OF THUNDERSTORMS IN
ASSOCIATION WITH THIS STRONG SHORTWAVE. A H5 WIND MAX OF 80 KNOTS
IS EXPECTED TO PUSH INTO SW MN...WITH H3 WINDS OF 130+ KNOTS. THE
NAM AND GFS BOTH DEPICT INTENSE UPPER LEVEL DIVERGENCE IN
ASSOCIATION WITH THIS FEATURE...AND THE SPC HAS OUR SOUTHWESTERN
CWA IN THE SLIGHT RISK FOR LATER TODAY AND THIS EVENING. THINK
THERE IS AN OPPORTUNITY FOR SEVERE STORMS...NAMELY DAMAGING WINDS
AND LARGE HAIL FOR A TIME LATER TODAY. WHILE SURFACE MOISTURE WILL
BE A BIT LACKING...STRONG DYNAMICS AND INTENSE SHEAR COULD MAKE UP
FOR ANY DEFICIENCY IN MOISTURE. AS A RESULT...WILL HIT POPS HARD
AS IT MOVES INTO THE CWA...AND THEN IT LOOKS LIKE IT WILL ROTATE
THROUGH THE AREA OVERNIGHT AND INTO SUNDAY. SHOULD BE A GOOD DEAL
OF CLOUD COVER AROUND ON SUNDAY MORNING...BUT THERE SHOULD OVERALL
BE AN IMPROVEMENT AS THE DAY WEARS ON WITH SOME SUNSHINE MOST
AREAS BY AFTERNOON. HIGHS TODAY AND SUNDAY WILL BE IN THE 60S WITH
A FEW 70 DEGREE READINGS SOUTH.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 AM CDT SAT SEP 20 2014

THE NORTHLAND CAN ANTICIPATE DRY AND WARMER THAN NORMAL WEATHER FOR
MUCH OF THE UPCOMING WEEK. SURFACE HIGH PRESSURE WILL MOVE THROUGH
THE MIDWEST AND GREAT LAKES REGION EARLY THIS WEEK WHICH WILL
PROMOTE CLEAR SKIES OVER THE NORTHLAND. SOUTHERLY FLOW WILL DEVELOP
TUESDAY IN THE WAKE OF THE PASSING HIGH PRESSURE...AND THE SOUTHERLY
FLOW PATTERN WILL CONTINUE THROUGH AT LEAST LATE THIS WEEK.

AN UPPER LEVEL LOW WILL MOVE OUT OF THE ROCKY MOUNTAINS INTO THE
CENTRAL/NORTHERN PLAINS DURING THE MONDAY AND TUESDAY TIMEFRAME.
THIS LOW COULD HELP DEVELOP SHOWERS AND STORMS OVER THE PLAINS AND
NORTHLAND WEDNESDAY AND WEDNESDAY NIGHT. THE GFS AND GEM ARE
INDICATING THIS UPPER LEVEL WILL GET CUT OFF FROM THE UPPER LEVEL
FLOW AND RETROGRADE BACK INTO THE PLAINS THURSDAY.

TEMPERATURES WILL LIKELY BE ABOUT 5 TO 10 DEGREES ABOVE NORMAL FOR
MUCH OF THE WEEK. THE WARMEST DAY MIGHT BE FRIDAY WITH HIGHS IN THE
UPPER 60S AND LOWER 70S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1237 PM CDT SAT SEP 20 2014

MVFR CLOUDS WERE GRADUALLY THINNING/DISSIPATING THIS AFTERNOON. WE
EXPECT KBRD/KHYR/KINL TO BECOME SCATTERED OVER THE NEXT 1 TO 2
HOURS. HOWEVER...ADDITIONAL DEVELOPMENT IS POSSIBLE AND WE HAVE
TEMPO GROUPS TO ACCOUNT FOR THAT IN MOST TAFS.

A STRONG COLD FRONT AND UPPER LEVEL WAVE WILL SPREAD
SHOWERS/STORMS INTO THE REGION THIS AFTERNOON/EVENING. KBRD WILL
BE FIRST TO SEE THEM. STRONG TO SEVERE STORMS WILL BE
POSSIBLE...MOST LIKELY TOWARD KBRD...AND LEAST LIKELY OVER THE
ARROWHEAD. A PERIOD OF GUSTY WINDS WILL OCCUR BEHIND THE FRONT.
WE EXPECT SOME LOWER CEILINGS TO OCCUR WITH THE
SHOWERS/STORMS...THEN LATER TONIGHT BEHIND THE FRONT. CEILINGS
WILL START TO LIFT LATE IN THE TAF PERIOD...BUT WILL MOST LIKELY
REMAIN MVFR.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  68  50  66  46 /  60  70  20   0
INL  64  47  65  42 /  60  70  10   0
BRD  70  49  67  44 /  60  60  10   0
HYR  71  50  65  42 /  50  70  30   0
ASX  70  48  62  44 /  40  70  30   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

$$

UPDATE...MILLER
SHORT TERM...DAP
LONG TERM...GROCHOCINSKI
AVIATION...MELDE





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