Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 131145 AAA
AFDDLH

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DULUTH MN
645 AM CDT SUN JUL 13 2014

.UPDATE...ISSUED FOR 12Z AVIATION DISCUSSION BELOW...


&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CDT SUN JUL 13 2014

THE COLD FRONT THAT WENT THROUGH THE NORTHLAND LAST NIGHT WAS
NEARLY OUT OF THE FORECAST AREA EARLY THIS MORNING WITH THE FRONT
JUST ON THE VERGE OF EXITING PRICE COUNTY. MUCH COOLER TEMPS WERE
ALREADY BEING SEEN IN NRN MN WHERE TEMPS WERE IN THE MID 40S...IN
CONTRAST TO THE LOWER 60S IN NORTHERN WI.

ANOTHER IN A SERIES OF S/WVS ROTATING AROUND UPPER LOW WILL AFFECT
THE NORTHLAND TODAY AND TONIGHT. SCATTERED RAIN SHOWERS OCCURRING
OVER SRN MANITOBA/NWRN ONTARIO WILL SPREAD SWRD TDY AND TONIGHT.
THE SHOWERS WILL ALSO BE AIDED BY STEEP LAPSE MID LEVEL LAPSE RATES
CAUSED BY CAA ALOFT. SUNSHINE THIS MORNING WILL GRADUALLY BE
REPLACE BY THE COLD AIR STRATOCUMULUS IN THE WAKE OF THE COLD
FRONT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM CDT SUN JUL 13 2014

ANOMALOUS MID LVL CLOSED LOW AND PARENT UPPER LEVEL TROF WILL SWING
ACROSS THE REGION MONDAY...THEN GRADUALLY WEAKEN AS IT SHIFTS EAST
INTO THE CENTRAL GREAT LAKES MIDWEEK. THE MID LVL PATTERN WILL THEN
TRANSITION GRADUALLY TO A WEST NORTHWEST FLOW ALOFT DURING THE END
OF THE WEEK. THIS WILL BE ACCOMPANIED BY AN INCREASE IN WARM AIR
ADVECTION IN LOW LVLS AND A CHANCE OF RAIN FAR NORTH FRIDAY.

PRECIP...CLOUDS...AND COLD ADVECTION WILL ENSURE A MUCH BELOW CLIMO
DAY MONDAY ACROSS THE CWA. BASED ON LATEST FCSTS OF SALIENT
FEATURES...MID LVL LOW AND DEEP LAYER MOISTURE...IT APPEARS THE AREA
FROM THE ERN ARROWHEAD SOUTH TO TWIN PORTS AND NORTHWEST WISCONSIN
WILL HAVE THE LOWEST MAX TEMPS. SREF PLUMES SHOW A MEAN TEMP FOR DLH
OF APPROX 57F..3 DEGREES ABOVE THE RECORD LOW MAX FOR THE DATE.
EITHER WAY..TEMPS WILL AVERAGE ABOUT 10 TO 20 DEGREES BELOW CLIMO
OVER MOST OF THE CWA. A CHALLENGE EXISTS TUESDAY REGARDING THE
EXISTING LOWER CLOUD DECK LEFT BEHIND BY THE DEEP CIRCULATION. THERE
ARE SOME CONFLICTING SIGNALS REGARDING PLACEMENT OF CLOUDS TUESDAY
AS SOME NWP SHOWS HIGHER CHC OF INSTABILITY CU DEVELOPING OVER SRN
CWA LATE MORNING... AND ADVECTING SOUTH OF THE CWA BY AFTERNOON.
GENERAL SYNOPTIC SCALE PATTERN WOULD FAVOR SOME AMOUNT OF CLOUD
COVER OVER THE ERN PART OF THE CWA WITH CLOSER PROXIMITY TO MOISTURE
ASSOCIATED WITH THE GT LAKES CIRCULATION. FCST 925H TEMPS TUESDAY OF
14C TO 15C SHOULD ALLOW MAX TEMPS TO JUMP INTO UPPER 60S TO NEAR
70...AND 70S AREA WIDE WEDNESDAY.  WARM ADVECTION PATTERN WILL
CONTINUE TO PUSH TEMPS UPWARDS LATE WEEK WITH MID TO UPPER 70S AND A
FEW 80S BY FRIDAY. AT THIS POINT THE FCST STRENGTH OF THE SFC HIGH
OVER THE REGION AND THE LACK OF SUFFICIENT DEEP LAYER MOISTURE
SHOULD RESTRICT PRECIP CHCS TO FAR NORTH MN ZONES FRIDAY. EVEN THAT
POTENTIAL MAY BE OVERDONE AS GFS IS ONLY MODEL DRIVING A WARM
FRONTAL BDRY PRECIP PATTERN ACROSS THE NORTH. OF MORE CONFIDENCE IS
THE APPROACH OF A FRONTAL BDRY WITH MID LVL TROF DURING THE WEEKEND.
WHILE BOTH GFS/ECMWF AGREE ON THIS GENERAL PATTERN THERE ARE TIMING
DIFFERENCES.THE EC IS FASTER IN PROGRESSING THE FORCING/PRECIP
EASTWARD THAN THE SLOWER GFS/GEM. WILL HAVE TO USE GENERIC CHC
WORDING FOR NOW UNTIL LATER THIS WEEK WHEN MODEL DISCREPANCIES
LESSEN AND ACTUAL SYNOPTIC REGIME DEVELOPS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 629 AM CDT SUN JUL 13 2014

VFR SHOULD PREVAIL WITH INITIAL PART OF FCST TODAY AND THIS EVENING.
STEEPENING LAPSE RATES MAY GENERATE A FEW SHOWERS TODAY SO USED
VCSH WORDING AT SOME SITES. LOCALLY GUSTY WINDS WILL DEVELOP AS
MOMENTUM IS TRANSFERRED DOWN FROM STRONGER WINDS AT TOP OF MIXING
LAYER. SECOND ASPECT OF FCST OCCURS OVERNIGHT AS UNUSUALLY STRONG
UPPER LEVEL TROF/CLOSED LOW MOVE SOUTH INTO THE CWA. A LARGE AREA
OF CLOUDS AND PRECIPITATION SHOULD MAKE ITS WAY PAST KINL/KHIB
TOWARDS KDLH. WILL START WITH MVFR CEILINGS/VIS FOR NOW BUT NEXT
FORECAST MAY NEED TO GO LOWER.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  67  50  59  48 /  20  40  70  20
INL  65  47  63  47 /  30  50  60  10
BRD  70  51  62  50 /  10  30  50  10
HYR  70  51  59  48 /  10  30  70  30
ASX  68  49  58  48 /  10  40  70  50

&&

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

$$

UPDATE...CANNON
SHORT TERM...CLC
LONG TERM...CLC
AVIATION...CANNON






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