000
FXUS63 KDLH 102020
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
320 PM CDT THU JUL 10 2014

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 320 PM CDT THU JUL 10 2014

AT 315PM/2015Z...SURFACE HIGH PRESSURE WAS CENTERED OVER THE
CENTRAL/EASTERN GREAT LAKES REGION. THE NORTHERN PLAINS HAD WARM
AND HUMID SOUTHERLY FLOW AHEAD OF LOW PRESSURE IN THE HIGH PLAINS.
WHILE MUCH OF THE NORTHLAND HAD CLEAR TO MOSTLY CLEAR
SKIES...THERE WAS INCREASING MID/HIGH CLOUD COVER IN THE WESTERN
FORECAST AREA. THIS WAS DUE TO BKN/OVC MID HIGH CLOUDS IN NW
MINNESOTA AND THE EASTERN DAKOTAS DUE TO A SHORTWAVE IN CENTRAL
NORTH DAKOTA MOVING TO THE EAST. THERE WERE SOME SHOWERS IN SOUTH
CENTRAL NORTH DAKOTA AND NORTHERN AND EASTERN SOUTH DAKOTA
ASSOCIATED WITH THIS SHORTWAVE.

TONIGHT...THERE IS SOMEWHAT LOW CONFIDENCE ON PCPN FOR THE
FORECAST AREA. THERE IS CONSIDERABLE DIFFERENCES BETWEEN THE
MODELS. SOME INDICATE THAT THE SHORTWAVE WILL DIVE SE IN THE UPPER
LEVEL FLOW...WHICH COULD THEN KEEP MOST PCPN ASSOCIATED WITH THE
SHORTWAVE SOUTH OF THE FORECAST AREA. OTHER MODELS INDICATE THAT
EVEN THOUGH THE PCPN MAY STAY NEAR THE FAR SOUTHERN BORDER FOR
THROUGH LATE TONIGHT...THAT THERE WILL BE A NORTHWARD SURGE OF
PCPN LATE TONIGHT...PROBABLY DUE TO THE INCREASING LOW LEVEL JET
AND MOISTURE TRANSPORT. AND OTHER MODELS ARE IN BETWEEN...MAINLY
LIMITING THE PCPN TO THE SOUTHERN FORECAST AREA. I DECIDED TO TAKE
A MIDDLE OF THE ROAD ROUTE AND NOT DEVIATE TOO MUCH FROM THE
PREVIOUS FORECAST. DESPITE SOME MODELS KEEPING THE FORECAST DRY
TONIGHT...I THINK IT IS REASONABLE TO PROVIDE LOW CHANCES FOR MUCH
OF THE FORECAST AREA DUE TO THE INCREASING LOW LEVEL JET AND
MOISTURE TRANSPORT.

FRIDAY...THERE COULD BE LINGERING WIDESPREAD SHOWERS AND STORMS
DURING THE MORNING FROM THE OVERNIGHT ELEVATED ACTIVITY...MAINLY
ACROSS THE EASTERN AND SOUTHERN FORECAST AREA. A COLD FRONT WILL
BEGIN TO MOVE INTO NE MINNESOTA DURING THE AFTERNOON. THE MODELS
ARE NOT IN GOOD AGREEMENT...BUT GENERALLY SUGGEST THERE COULD BE
SHOWERS AND STORMS ALONG OR IN ADVANCE OF THE COLD FRONT. SOME
STORMS COULD BE STRONG WITH SMALL HAIL AND GUSTY WINDS. THE
NAM12...GFS...AND SREF ARE INDICATING THAT A RIBBON OF ABOUT 500
TO 1500 J/KG OF MIXED LAYER CAPE WILL DEVELOP...PROVIDED ENOUGH
DAYTIME HEATING...AHEAD OF THE COLD FRONT. CONSIDERING THE DEEP
LAYER (0 TO 6 KM) WIND SHEAR OF 30 TO 40 KNOTS...THERE COULD BE
SOME ORGANIZED STORM CELLS. AT THE TIME OF THIS DISCUSSION...THE
STORM PREDICTION CENTER HAD A SEE TEXT AND 5 PERCENT RISK OF
SEVERE WEATHER. IF IT APPEARS TOMORROW THAT THERE WILL BE ENOUGH
HEATING DURING THE AFTERNOON TO COMPENSATE FOR THE MORNING CLOUD
COVER FROM THE OVERNIGHT CONVECTION...THEN THERE COULD BE A
GREATER RISK OF SEVERE WEATHER. HIGH TEMPERATURES SHOULD GENERALLY
BE BETWEEN THE MID TO UPPER 70S. IT WILL BE COOLER ALONG THE NORTH
SHORE DUE TO THE SOUTHERLY FLOW OFF OF THE LAKE.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU JUL 10 2014

MODEL DIFFERENCES SURFACE FRIDAY NIGHT AS A COLD FRONT IS EXPECTED
TO DEPART THE EASTERN TIER OF THE FA BY 06Z SATURDAY. ECMWF IS
BULLISH WITH PCPN...ESPECIALLY WITH A SECONDARY BATCH ALONG WHAT
IT DETERMINES TO BE A WEAK SFC TROF. OTHER MODELS DO NOT HAVE THIS
FEATURE AND HAVE IGNORED THE ECMWF THROUGH 12Z SATURDAY. CONSENSUS
WOULD HAVE POPS OVER THE EASTERN EDGE OF THE FA THROUGH 03Z...THEN
JUST OVER SOUTHERN PRICE COUNTY THROUGH 06Z IN THE VCNTY OF THE
DEPARTING FRONT. HIGH PRESSURE BUILDS OVER THE FA FROM THE W AFTER
06Z SATURDAY AND HAVE REMOVED THE POPS. DID ADD SOME PATCHY FOG
WITH THE EXPECTED LIGHT WIND. SATURDAY IS THE BEGINNING OF HOW A
COLD UPPER LEVEL LOW WILL AFFECT THE FA THROUGH TUESDAY. PIECES OF
EMBEDDED ENERGY IN FAST FLOW ALOFT WILL PASS OVER THE FA
PERIODICALLY THROUGH TUESDAY. MEANWHILE...A COLD FRONT PUSHES
THROUGH SATURDAY NIGHT AND SUNDAY. THESE FEATURES WILL WARRANT
KEEPING POPS AFFECTING THE FA THROUGH TUESDAY. TIMING WILL BE
DIFFICULT IN THE FAST FLOW. COOL HIGH PRESSURE FINALLY SETTLES
OVER THE AREA TUESDAY NIGHT AND WEDNESDAY AS THE CLOSED UPPER LOW
WILL HAVE DEPARTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1238 PM CDT THU JUL 10 2014

VFR THROUGH THE FORECAST PERIOD. GUSTY SFC WINDS THIS AFTERNOON
WILL DIMINISH WITH SUNSET. KEPT THE GENERAL TIMING OF SHOWERS
AND POSSIBLE STORMS INTO THE TERMINALS AFTER 05Z FROM W TO E.
THERE WILL BE A PERIOD OF LLWS AFTER 04Z AS A LLJ INTERACTS WITH
THE PCPN. THE LLJ SHOULD MOVE E OF THE TERMINALS GRADUALLY FROM
06Z THROUGH 14Z. SOME VCSH POSSIBLE AGAIN AFTER 14Z AS A COLD
FRONT DROPS SEWD FROM CENTRAL CANADA.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  60  74  58  78 /  60  60  10  10
INL  64  79  53  77 /  30  50  10  10
BRD  66  81  60  80 /  70  60  10  10
HYR  65  76  60  81 /  60  60  20  10
ASX  62  75  58  77 /  40  60  20  10

&&

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

$$

SHORT TERM...GROCHOCINSKI
LONG TERM...GSF
AVIATION...GSF