Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/03/14
AREA FORECAST DISCUSSION
NWS MIAMI FL
142 PM EDT THU MAY 1 2014
.AVIATION...
ISOLATED SHOWERS WERE DEVELOPING ACROSS THE INTERIOR AND SLOWLY
MOVING NORTH. A FEW SHOWERS COULD GET NEAR KPBI THIS AFTERNOON.
OTHERWISE...MAINLY VFR CONDITIONS WITH SOUTHEAST WINDS AROUND 15
KNOTS WILL CONTINUE THROUGH THE AFTERNOON HOURS AT THE EAST COAST
TAF SITES. WINDS HAVE SHIFTED THE SOUTH AT KAPF...AND A SOUTH TO
SOUTHWEST WIND AT 10-15 KNOTS WILL CONTINUE THROUGH EARLY THIS
EVENING BEFORE SUBSIDING. A LIGHT SOUTHEAST FLOW IS FORECAST
OVERNIGHT. THE WINDS WILL SHIFT SLIGHTLY MORE TO THE SOUTH ON
FRIDAY AS A FRONTAL BOUNDARY SLIDES INTO CENTRAL FLORIDA.
&&
.PREV DISCUSSION... /ISSUED 958 AM EDT THU MAY 1 2014/
UPDATE...
MADE SOME MINOR CHANGES EARLIER THIS MORNING TO TAKE OUT MENTION
OF SMOKE OVER THE INTERIOR. THE WILDFIRES IN COLLIER AND GLADES
COUNTIES HAVE MOSTLY BEEN CONTAINED WITH NO REPORTS OF SMOKE
RESTRICTING VISIBILITY. THE 12Z MFL SOUNDING SHOWS A LITTLE
MOISTURE INCREASE IN THE LOW LEVELS BUT STILL VERY DRY ALOFT WITH
PWAT INCREASING TO 1.5 INCHES. THE MID LEVEL LAPSE RATES ARE ALSO
LESS THAN IN THE PREVIOUS FEW DAYS SO THE FORECAST OF MOSTLY
INTERIOR LATE AFTERNOON SCATTERED CONVECTION STILL LOOKS GOOD WITH
THE HRRR SHOWING DEVELOPMENT AROUND 18Z AND PERSISTING INTO THE
EARLY EVENING.
KOB
PREV DISCUSSION... /ISSUED 732 AM EDT THU MAY 1 2014/
AVIATION...
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE END OF THE TAF
PERIOD. LIGHT SOUTHEAST WINDS EARLY THIS MORNING WILL INCREASE TO
10-15 KNOTS BY 15Z AT THE EAST COAST TAF SITES. AT KAPF...THE GULF
COAST SEA BREEZE IS FORECAST TO MOVE INLAND THIS AFTERNOON. A FEW
SHOWERS MAY GET NEAR KPBI THIS MORNING AS STREAMER SHOWERS MOVE
ACROSS THE ATLANTIC WATERS. OTHERWISE...SHOWERS AND STORMS ARE
FORECAST TO BE ACROSS THE INTERIOR THIS AFTERNOON. A FEW SHOWERS
OR STORMS COULD GET NEAR KAPF THIS AFTERNOON...BUT PROBABILITIES
ARE TOO LOW TO PUT IN TAF AT THIS TIME.
PREV DISCUSSION... /ISSUED 317 AM EDT THU MAY 1 2014/
RISK OF RIP CURRENTS WILL CONTINUE ALONG EAST COAST BEACHES
THROUGH THE WEEKEND...
BETTER CHANCE FOR RAIN IN SOUTH FLORIDA LATE THIS WEEK INTO
THIS WEEKEND BEFORE DRY WEATHER RETURNS FOR EARLY NEXT WEEK...
SHORT TERM...
LOW PRESSURE OVER THE GREAT LAKES WILL CONTINUE TO MOVE NORTHEAST
INTO CANADA TODAY...AS A COLD FRONT OVER THE FLORIDA PANHANDLE
MOVES SLOWLY SOUTHEAST INTO NORTH FLORIDA. THE FRONT WILL THEN
STALL OVER CENTRAL FLORIDA ON FRIDAY...AS LOW PRESSURE DEVELOPS IN
THE CENTRAL GULF OF MEXICO. THIS WILL KEEP THE STEERING FLOW OVER
SOUTH FLORIDA IN A SOUTHEASTERLY DIRECTION TODAY BEFORE SWINGING TO
A SOUTHERLY DIRECTION ON FRIDAY. THE EAST AND WEST COAST SEA BREEZES
WILL ALSO DEVELOP EACH DAY...SO ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED OVER THE NORTHERN INTERIOR AREAS
TODAY...BEFORE EXPANDING INTO THE NORTHEAST PORTIONS OF SOUTH
FLORIDA ON FRIDAY. REST OF SOUTH FLORIDA SHOULD BE DRY TODAY BEFORE
ISOLATED SHOWERS RETURN FOR FRIDAY.
THE LOW OVER THE CENTRAL GULF OF MEXICO WILL MOVE EAST ALONG THE
STATIONARY FRONT AND THROUGH CENTRAL FLORIDA ON SATURDAY. THIS WILL
ALLOW FOR THE STEERING FLOW TO SWING TO A SOUTHWESTERLY DIRECTION ON
SATURDAY ALLOWING FOR DEEPER TROPICAL MOISTURE TO WORK INTO THE AREA
FROM THE SOUTH. SO SCATTERED POPS WILL CONTINUE OVER SOUTH FLORIDA
ON SATURDAY ALONG WITH SOME THUNDERSTORMS. THE SOUTHWEST WIND FLOW
WILL ALSO ALLOW FOR HIGHS TO WARM UP INTO THE LOWER 90S OVER THE
EAST COAST METRO AREAS WHICH COULD GET CLOSE TO THE RECORD HIGHS.
MORE DETAIL DISCUSSION ON THE RECORD HIGHS IN THE CLIMATE SECTION
BELOW.
THE LOW WILL CONTINUE TO MOVE EAST INTO THE ATLANTIC WATERS
SATURDAY NIGHT INTO SUNDAY. THIS WILL ALLOW FOR THE STATIONARY
FRONT TO MOVE SOUTH AS A COLD FRONT THROUGH SOUTH FLORIDA SATURDAY
NIGHT. THIS FRONT WILL BRING IN DRIER AND COOLER WEATHER TO SOUTH
FLORIDA FOR SUNDAY.
LONG TERM...
HIGH PRESSURE WILL BUILD INTO THE FLORIDA PENINSULA FROM THE NORTH
EARLY NEXT WEEK BEFORE SLOWLY MOVING EAST INTO THE WESTERN
ATLANTIC WATERS FOR THE MIDDLE TO END OF NEXT WEEK. THIS WILL KEEP
THE WEATHER OVER SOUTH FLORIDA DRY FOR NEXT WEEK. THE PWAT VALUES
WILL ALSO BE AROUND 0.6 TO 0.8 INCHES OVER SOUTH FLORIDA FOR NEXT
WEEK WHICH IS 2 STANDARD DEVIATIONS BELOW THE NORMAL PWAT OF 1.6
TO 1.7 INCHES FOR THIS TIME OF YEAR.
MARINE...
THE WINDS WILL BE FROM THE SOUTHEAST AT 10 TO 15 KNOTS TODAY BEFORE
SWINGING TO A MORE SOUTHERLY DIRECTION FOR FRIDAY INTO EARLY PART
OF THE WEEKEND. THE WINDS WILL THEN SWING TO A NORTHERLY DIRECTION
ON SUNDAY INTO EARLY NEXT WEEK...AS WIND SPEEDS REMAIN AROUND 15
KNOTS. THIS WILL KEEP THE SEAS BELOW 6 FEET IN BOTH THE ATLANTIC
AND GULF WATERS OF SOUTH FLORIDA THROUGH EARLY THIS WEEK BEFORE
INCREASING TO AROUND 7 FEET BY LATE THIS WEEKEND.
SMALL NORTHEAST SWELL WILL BUILD INTO SOUTH FLORIDA ATLANTIC
WATERS TODAY INTO THIS WEEKEND FROM THE NORTH. THESE NORTHEAST
SWELLS WILL ALLOW FOR THE CONTINUATION OF THE RISK OF RIP CURRENTS
ALONG THE EAST COAST BEACHES OF SOUTH FLORIDA THROUGH THE WEEKEND.
CLIMATE...
HERE ARE THE FORECAST HIGHS AND THE RECORD HIGHS FOR THE EAST
COAST AIRPORTS FOR THIS SATURDAY.
CITIES FORECAST HIGHS RECORD HIGHS
MIA 92 91 - 1896
FLL 91 91 - 1920
PBI 90 91 - 1986
MIA BEACH 90 91 - 1964
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 87 73 90 / 10 30 30 50
FORT LAUDERDALE 77 88 76 91 / 10 20 20 40
MIAMI 76 88 75 92 / 10 20 20 40
NAPLES 73 87 72 85 / 10 20 20 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH FRIDAY MORNING FOR FLZ168.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....30/KOB
AVIATION...84/AK
AREA FORECAST DISCUSSION
NWS MIAMI FL
958 AM EDT THU MAY 1 2014
.UPDATE...
MADE SOME MINOR CHANGES EARLIER THIS MORNING TO TAKE OUT MENTION
OF SMOKE OVER THE INTERIOR. THE WILDFIRES IN COLLIER AND GLADES
COUNTIES HAVE MOSTLY BEEN CONTAINED WITH NO REPORTS OF SMOKE
RESTRICTING VISIBILITY. THE 12Z MFL SOUNDING SHOWS A LITTLE
MOISTURE INCREASE IN THE LOW LEVELS BUT STILL VERY DRY ALOFT WITH
PWAT INCREASING TO 1.5 INCHES. THE MID LEVEL LAPSE RATES ARE ALSO
LESS THAN IN THE PREVIOUS FEW DAYS SO THE FORECAST OF MOSTLY
INTERIOR LATE AFTERNOON SCATTERED CONVECTION STILL LOOKS GOOD WITH
THE HRRR SHOWING DEVELOPMENT AROUND 18Z AND PERSISTING INTO THE
EARLY EVENING.
KOB
&&
.PREV DISCUSSION... /ISSUED 732 AM EDT THU MAY 1 2014/
AVIATION...
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE END OF THE TAF
PERIOD. LIGHT SOUTHEAST WINDS EARLY THIS MORNING WILL INCREASE TO
10-15 KNOTS BY 15Z AT THE EAST COAST TAF SITES. AT KAPF...THE GULF
COAST SEA BREEZE IS FORECAST TO MOVE INLAND THIS AFTERNOON. A FEW
SHOWERS MAY GET NEAR KPBI THIS MORNING AS STREAMER SHOWERS MOVE
ACROSS THE ATLANTIC WATERS. OTHERWISE...SHOWERS AND STORMS ARE
FORECAST TO BE ACROSS THE INTERIOR THIS AFTERNOON. A FEW SHOWERS
OR STORMS COULD GET NEAR KAPF THIS AFTERNOON...BUT PROBABILITIES
ARE TOO LOW TO PUT IN TAF AT THIS TIME.
PREV DISCUSSION... /ISSUED 317 AM EDT THU MAY 1 2014/
.RISK OF RIP CURRENTS WILL CONTINUE ALONG EAST COAST BEACHES
THROUGH THE WEEKEND...
.BETTER CHANCE FOR RAIN IN SOUTH FLORIDA LATE THIS WEEK INTO
THIS WEEKEND BEFORE DRY WEATHER RETURNS FOR EARLY NEXT WEEK...
SHORT TERM...
LOW PRESSURE OVER THE GREAT LAKES WILL CONTINUE TO MOVE NORTHEAST
INTO CANADA TODAY...AS A COLD FRONT OVER THE FLORIDA PANHANDLE
MOVES SLOWLY SOUTHEAST INTO NORTH FLORIDA. THE FRONT WILL THEN
STALL OVER CENTRAL FLORIDA ON FRIDAY...AS LOW PRESSURE DEVELOPS IN
THE CENTRAL GULF OF MEXICO. THIS WILL KEEP THE STEERING FLOW OVER
SOUTH FLORIDA IN A SOUTHEASTERLY DIRECTION TODAY BEFORE SWINGING TO
A SOUTHERLY DIRECTION ON FRIDAY. THE EAST AND WEST COAST SEA BREEZES
WILL ALSO DEVELOP EACH DAY...SO ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED OVER THE NORTHERN INTERIOR AREAS
TODAY...BEFORE EXPANDING INTO THE NORTHEAST PORTIONS OF SOUTH
FLORIDA ON FRIDAY. REST OF SOUTH FLORIDA SHOULD BE DRY TODAY BEFORE
ISOLATED SHOWERS RETURN FOR FRIDAY.
THE LOW OVER THE CENTRAL GULF OF MEXICO WILL MOVE EAST ALONG THE
STATIONARY FRONT AND THROUGH CENTRAL FLORIDA ON SATURDAY. THIS WILL
ALLOW FOR THE STEERING FLOW TO SWING TO A SOUTHWESTERLY DIRECTION ON
SATURDAY ALLOWING FOR DEEPER TROPICAL MOISTURE TO WORK INTO THE AREA
FROM THE SOUTH. SO SCATTERED POPS WILL CONTINUE OVER SOUTH FLORIDA
ON SATURDAY ALONG WITH SOME THUNDERSTORMS. THE SOUTHWEST WIND FLOW
WILL ALSO ALLOW FOR HIGHS TO WARM UP INTO THE LOWER 90S OVER THE
EAST COAST METRO AREAS WHICH COULD GET CLOSE TO THE RECORD HIGHS.
MORE DETAIL DISCUSSION ON THE RECORD HIGHS IN THE CLIMATE SECTION
BELOW.
THE LOW WILL CONTINUE TO MOVE EAST INTO THE ATLANTIC WATERS
SATURDAY NIGHT INTO SUNDAY. THIS WILL ALLOW FOR THE STATIONARY
FRONT TO MOVE SOUTH AS A COLD FRONT THROUGH SOUTH FLORIDA SATURDAY
NIGHT. THIS FRONT WILL BRING IN DRIER AND COOLER WEATHER TO SOUTH
FLORIDA FOR SUNDAY.
LONG TERM...
HIGH PRESSURE WILL BUILD INTO THE FLORIDA PENINSULA FROM THE NORTH
EARLY NEXT WEEK BEFORE SLOWLY MOVING EAST INTO THE WESTERN
ATLANTIC WATERS FOR THE MIDDLE TO END OF NEXT WEEK. THIS WILL KEEP
THE WEATHER OVER SOUTH FLORIDA DRY FOR NEXT WEEK. THE PWAT VALUES
WILL ALSO BE AROUND 0.6 TO 0.8 INCHES OVER SOUTH FLORIDA FOR NEXT
WEEK WHICH IS 2 STANDARD DEVIATIONS BELOW THE NORMAL PWAT OF 1.6
TO 1.7 INCHES FOR THIS TIME OF YEAR.
MARINE...
THE WINDS WILL BE FROM THE SOUTHEAST AT 10 TO 15 KNOTS TODAY BEFORE
SWINGING TO A MORE SOUTHERLY DIRECTION FOR FRIDAY INTO EARLY PART
OF THE WEEKEND. THE WINDS WILL THEN SWING TO A NORTHERLY DIRECTION
ON SUNDAY INTO EARLY NEXT WEEK...AS WIND SPEEDS REMAIN AROUND 15
KNOTS. THIS WILL KEEP THE SEAS BELOW 6 FEET IN BOTH THE ATLANTIC
AND GULF WATERS OF SOUTH FLORIDA THROUGH EARLY THIS WEEK BEFORE
INCREASING TO AROUND 7 FEET BY LATE THIS WEEKEND.
SMALL NORTHEAST SWELL WILL BUILD INTO SOUTH FLORIDA ATLANTIC
WATERS TODAY INTO THIS WEEKEND FROM THE NORTH. THESE NORTHEAST
SWELLS WILL ALLOW FOR THE CONTINUATION OF THE RISK OF RIP CURRENTS
ALONG THE EAST COAST BEACHES OF SOUTH FLORIDA THROUGH THE WEEKEND.
CLIMATE...
HERE ARE THE FORECAST HIGHS AND THE RECORD HIGHS FOR THE EAST
COAST AIRPORTS FOR THIS SATURDAY.
CITIES FORECAST HIGHS RECORD HIGHS
MIA 92 91 - 1896
FLL 91 91 - 1920
PBI 90 91 - 1986
MIA BEACH 90 91 - 1964
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 87 73 / 20 10 30 30
FORT LAUDERDALE 88 77 88 76 / 20 10 20 20
MIAMI 89 76 88 75 / 20 10 20 20
NAPLES 89 73 87 72 / 10 10 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH FRIDAY MORNING FOR FLZ168.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
315 AM EDT THU MAY 01 2014
.SYNOPSIS
07Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW A HIGHLY
AMPLIFIED UPPER LEVEL IN PLACE OVER THE CONUS...HIGHLIGHTED BY THE
STUBBORN DEEP LONGWAVE TROUGH/CLOSED LOW FEATURE ACROSS THE CENTRAL
STATES THAT HAS BEEN RESPONSIBLE FOR SO MUCH INCLEMENT/SEVERE
WEATHER AND FLOODING THE PAST SEVERAL DAYS TO THE NORTH OF OUR AREA.
THE GOOD NEWS FOR THE CONTINUED SEVERE WEATHER THREAT TO OUR NORTH
IS THAT THIS SYSTEM IS BEGINNING TO FILL AND DE-AMPLIFY/EJECT OFF TO
THE EAST AND NORTHEAST. HOWEVER...AS THIS OCCURS WE WILL SEE THE
UPPER RIDGE THAT HAS BEEN OVER OUR HEADS THE PAST SEVERAL DAYS PUSH
OFF INTO THE WESTERN ATLANTIC AND BE REPLACED BY AN INCREASINGLY
CYCLONIC AND UNSETTLED FLOW ALOFT. ONE FEATURE OF NOTE THAT WILL
HAVE AN IMPACT ON OUR WEATHER HEADING INTO THE BEGINNING OF THE
WEEKEND (ONE MIGHT SAY THE MAJOR PLAYER)...IS A SHORTWAVE
TROUGH/IMPULSE BEGINNING TO ROUND THE BASE OF THE MAIN TROUGH FROM
THE FOUR-CORNERS REGION TOWARD TH SOUTHERN PLAINS. LATER TONIGHT
INTO THE WEEKEND...THIS ENERGY WILL QUICKLY EJECT EASTWARD ALONG THE
NORTHERN GULF COAST AND RESULT IN AN INCREASINGLY UNSETTLED/SHOWERY
PATTERN FOR OUR REGION DURING FRIDAY AND SATURDAY.
AT THE SURFACE...FORECAST AREA RESIDES WITHIN A WEAK GRADIENT
PATTERN BETWEEN SURFACE RIDGING OVER THE WESTERN ATLANTIC...AND A
FRONTAL SYSTEM EXTENDING FROM THE CENTRAL GULF OF MEXICO
NORTHEASTWARD TO THE FL PANHANDLE/GA/CAROLINAS. THIS FRONT WILL
SLOWLY SLIP SOUTHEAST INTO THE EASTERN GULF OF MEXICO/CENTRAL FL
PENINSULA DURING THE NEXT 24 HOURS...AND THEN BECOME
QUASI-STATIONARY THROUGH EARLY SATURDAY. THE APPROACHING AND PASSING
SHORTWAVE TROUGH LATER SATURDAY/SATURDAY NIGHT WILL GIVE THE FINAL
MASS FIELDS/MOMENTUM PUSH THE FRONT SOUTH OF THE FORECAST AREA...
AND CLEAR OUR WEATHER OUT FOR THE SECOND HALF OF THE WEEKEND.
EARLIER CONVECTION ASSOCIATED WITH THE COLLIDING SEA-BREEZES OVER
THE INTERIOR...AND ALSO THE RESIDUAL COLD POOL OUTFLOW SHOWERS THAT
CAME SOUTH ALONG THE COAST FROM LAST NIGHTS FL PANHANDLE CONVECTION
HAVE DISSIPATED...AND WE ARE NOW LOOKING AT MOSTLY DRY...BUT
WARM/HUMID CONDITIONS TO START OUT THE MORNING. CURRENT OBSERVATIONS
SHOW TEMPERATURES ARE GENERALLY IN THE UPPER 60S TO MIDDLE 70S UNDER
PARTLY CLOUDY SKIES.
&&
.SHORT TERM (TODAY AND TONIGHT)...
TODAY...
UPPER LEVEL RIDGE GIVES UP INFLUENCE ON THE FLORIDA PENINSULA AS IT
SHIFT EASTWARD IN RESPONSE TO THE OPENING UP AND RENEWED EASTWARD
PROGRESSION OF THE LARGE UPPER LOW THAT HAS BEEN SPINNING OVER THE
CENTRAL CONUS FOR SEVERAL DAYS. ONLY SUBTLE HEIGHT FALLS ARE PROGGED
BY NWP OVER THE PENINSULA TODAY/TONIGHT. HOWEVER...THE FLOW WILL
VERY SLOWLY BECOME INCREASINGLY CYCLONIC IN NATURE...WITH A STEADY
INCREASE IN COLUMN MOISTURE...ESPECIALLY ALONG AND TO THE NORTH OF
THE I-4 CORRIDOR.
SURFACE COLD FRONT CURRENTLY JUST TO THE NORTHWEST OF THE FORECAST
AREA WILL SLOWLY SINK SOUTHEASTWARD AND BECOME QUASI-STATIONARY OVER
THE NORTHERN/CENTRAL FL PENINSULA LATE TODAY AND TONIGHT.
THE SURFACE FOCUS ALONG THIS BOUNDARY IS CURRENTLY FAIRLY WEAK...AND
UPPER LEVEL SYNOPTIC SUPPORT FOR ASCENT IS VERY WEAK TO NEUTRAL IN
NATURE. WOULD ONLY BE EXPECTING A LIMITED COVERAGE OF SHOWERS FOR
THE NATURE COAST GIVEN THE LESS THAN FAVORABLE FOCUSING MECHANISMS
FOR ASCENT. HOWEVER...THE ADDED FOCUS OF THE SEA-BREEZE MAY BE
ENOUGH TO GIVE THIS ASCENT A BOOST AND RESULT IN A FEW MORE VIGOROUS
CONVECTIVE CELLS ALONG THE NATURE COAST I-75 CORRIDOR THIS
AFTERNOON. THE SEA BREEZE WILL BE EVEN MORE DEFINED FROM TAMPA BAY
SOUTHWARD DOWN THE SUN COAST ZONES. AS THIS BOUNDARY MOVES INLAND
THIS AFTERNOON AND EVENTUALLY FEELS THE INFLUENCE OF THE EAST COAST
SEA-BREEZE OVER THE INTERIOR...ANOTHER ROUND OF SHOWERS/STORMS IS
POSSIBLE...IN SIMILAR FASHION TO PREVIOUS COUPLE OF DAYS. HI-RES
CONVECTION ALLOWING MODEL SUITE IS IN AGREEMENT THAT AT LEAST A
SCATTERING OF STORMS SHOULD BECOME ESTABLISHED OVER THE INTERIOR
CENTRAL/SOUTHERN ZONES... ESPECIALLY DURING THE SECOND HALF OF THE
AFTERNOON AND EARLY EVENING HOURS. HAVE THE HIGHEST RAIN CHANCES
ALONG THE I-75 CORRIDOR OF THE NATURE COAST...AND THEN INLAND FROM
THE I-75 CORRIDOR FURTHER SOUTH. RAIN CHANCES THEN FALL QUICKLY AS
ONE HEADS BACK TOWARD THE COAST WITHIN THE POST SEA-BREEZE
ENVIRONMENT.
TONIGHT...
SCT SHOWERS/STORMS OVER THE INTERIOR WILL FADE WITH THE LOSS OF
DIURNAL HEATING AND SEA-BREEZE CONVERGENCE/FOCUS WITHIN A FEW HOURS
OF SUNSET. FOR A WHILE LATE THIS EVENING CONDITIONS MAY BE RATHER
QUIET/DRY ACROSS THE REGION. HOWEVER IT APPEARS THAT THIS WILL BE
ONLY TEMPORARY AS THE SYNOPTIC PATTERN QUICKLY TRANSITIONS TO ONE
SUPPORTIVE OF MORE ORGANIZED SHOWERS MOVING BACK INTO THE NATURE
COAST. UPPER TROUGH BEGINS TO EJECT EASTWARD CONTINUING THE
TRANSITION TO A MORE CYCLONIC FLOW ALOFT OVER THE FL PENINSULA.
GUIDANCE IS IN AGREEMENT OF STRENGTHENING WINDS FIELDS AHEAD OF THIS
TROUGH AND RESULTING IN INCREASING/DEFINED LOW LEVEL CONVERGENCE
ALONG THE STATIONARY FRONTAL BOUNDARY. INTO THE LATE NIGHT
HOURS...THIS MORE EFFICIENT FRONTAL FOCUS ALONG WITH ADDED
ISENTROPIC UPGLIDE ALONG THE 300-305K SURFACES TO THE NORTH OF THE
SURFACE BOUNDARY...AND DEEP LAYER SUBTLE QVECTOR CONVERGENCE IS
PROGGED TO RESULT IN AN EXPANDING AREA OF SHOWERS/STORMS OVER THE
NORTHEAST GULF OF MEXICO THAT WILL THEN QUICKLY MOVE TOWARD THE
FLORIDA WEST COAST. THESE SHOWERS DO NOT LOOK TO ARRIVE UNTIL VERY
LATE AT NIGHT...AND WILL BE PRIMARILY TO THE NORTH OF I-4. HAVE KEPT
ISOLATED THUNDER MENTION IN THE GRIDS FOR THESE AREAS NORTH OF TAMPA
BAY LATE TONIGHT. BOUNDARY LAYER CAPE PER GFS/NAM SUGGEST THAT THERE
WILL NOT BE ANY SURFACE BASED STORMS...HOWEVER SHOWALTER INDICES ARE
RIGHT AROUND ZERO SUGGESTING ENOUGH ELEVATED INSTABILITY FOR UPDRAFT
CHARGE SEPARATION AND SOME THUNDER POTENTIAL.
&&
.MID TERM (FRIDAY THROUGH SATURDAY)...
THE PERIOD BEGINS WITH AN UPPER LEVEL SHORT WAVE TROUGH ACROSS THE
SOUTHERN PLAINS AND WESTERN GULF COASTAL AREA ALONG WITH A SURFACE
BOUNDARY ACROSS NORTHERN FL...FROM THE SOUTHWEST GULF TO THE
ATLANTIC WATERS OF THE SOUTHEAST U.S. THESE FEATURES MOVE
EASTWARD...WITH THE UPPER SHORT WAVE TROUGH OVER THE SOUTHEASTERN
STATES SAT AFTERNOON AND THE BOUNDARY ACROSS THE SOUTHERN HALF OF
THE STATE. THE LATEST GFS AND ECMWF ARE FAIRLY CONSISTENT WITH THESE
FEATURES. ALTHOUGH THE GFS IS SLIGHTLY FASTER WITH THE UPPER SYSTEM
AND WHILE BOTH FORM WAVES ON THE BOUNDARY...THE TIMING AND LOCATION
VARY SOME. THE FORECAST WILL BE FOR MOSTLY CLOUDY TO CLOUDY SKIES
WITH SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS...WITH
THE BEST ODDS INITIALLY IN THE NORTH BUT SLOWLY SHIFTING TO THE
SOUTH THROUGH THE PERIOD.
&&
.LONG TERM (SUNDAY THROUGH NEXT WEDNESDAY)...
SAT NIGHT AND SUN - THE AXIS OF THE UPPER TROUGH SHIFTS EAST OF FL
WITH THE BOUNDARY EXITING SOUTH FL AS HIGH PRESSURE BUILDS INTO THE
WESTERN GULF. SKIES BEGIN TO CLEAR FROM THE NORTH AS RAIN ODDS TREND
DOWN AND EXIT BY MORNING.
SUN NIGHT THROUGH WED - UPPER LEVEL RIDGING BUILDS NORTH OVER THE
MID-CONUS THEN SLIDES TO THE EASTERN CONUS AS THE WESTERN GULF
SURFACE HIGH MIGRATES ACROSS FL TO THE ATLANTIC...AS IT RIDGES BACK
TO THE GULF. THIS PATTERN WILL RESULT IN MAINLY DRY CONDITIONS AND
TEMPERATURES IN THE NEAR NORMAL RANGE.
&&
.AVIATION...
GENERAL VFR CONDITIONS ARE BEGIN EXPERIENCED ACROSS WEST-CENTRAL AND
SOUTHWEST FLORIDA THIS MORNING. A FEW POCKETS OF MVFR CIGS ARE
POSSIBLE IN THE COUPLE HOURS EITHER SIDE OF SUNRISE...BUT COVERAGE
IS TOO LOW TO INCLUDE IN CURRENT TAFS. SEA BREEZE DEVELOPMENT WILL
TURN WINDS ONSHORE AND BECOME GUSTY 10-15 KNOTS FOR THE AFTERNOON
NEAR THE COAST. A SCATTERING OF SHOWERS/STORMS ARE POSSIBLE OVER THE
INTERIOR DURING THE AFTERNOON...WITH KLAL SEEING THE BEST CHANCES
FOR A BRIEF STORM. A WEAK COLD FRONT WILL ALSO BE DROPPING SOUTH
INTO THE NATURE COAST. A FEW SHOWERS DURING THE AFTERNOON ARE NOT
OUT OF THE QUESTION ALONG THIS FEATURE FOR KTPA/KPIE...HOWEVER...
MOST OF THIS SHOWER ACTIVITY SHOULD REMAIN NORTH OF THE I-4 CORRIDOR.
&&
.MARINE...
A COLD FRONT WILL SLOWLY DROP SOUTH INTO THE NORTHEAST GULF OF
MEXICO TODAY AND THEN STALL IN PLACE NEAR OR JUST NORTH OF TARPON
SPRINGS TONIGHT THROUGH EARLY SATURDAY. THIS FRONT WILL THEN BEGIN
TO MOVE AGAIN AND DROP SOUTH...OUT OF THE FORECAST WATERS LATE
SATURDAY AND SATURDAY NIGHT. NUMEROUS SHOWERS AND STORMS ARE
EXPECTED OVER THE COASTAL WATERS FRIDAY INTO AT LEAST THE FIRST
HALF OF SATURDAY ASSOCIATED WITH THIS FRONT. A BRIEF PERIOD OF NEAR
CAUTIONARY LEVEL WINDS ARE EXPECTED IN THE WAKE OF THE FRONT LATER
SATURDAY THROUGH SUNDAY MORNING BEFORE HIGH PRESSURE BECOMES
ESTABLISHED OVER THE EASTERN GULF OF MEXICO FOR THE EARLY PORTION OF
NEXT WEEK...RESULTING IN LIGHT WINDS AND LOW SEAS.
&&
.FIRE WEATHER...
MOIST FLOW AHEAD OF AN APPROACHING FRONT WILL KEEP RELATIVE HUMIDITY
VALUES WELL ABOVE CRITICAL LEVELS TODAY. DISPERSION VALUES WILL BE
ON THE HIGH SIDE AWAY FROM THE COAST. THE FRONT WILL STALL ACROSS
THE REGION TODAY AND SATURDAY PROVIDING NUMEROUS SHOWERS AND
ISOLATED STORMS TO THE FORECAST...ESPECIALLY FOR THE CENTRAL AND
NORTHERN FLORIDA PENINSULA. RELATIVE HUMIDITY VALUES WILL REMAIN
WELL ABOVE CRITICAL LEVELS THROUGH SATURDAY. SOMEWHAT DRIER AIR WILL
FILTER IN THE REGION FOR THE SECOND HALF OF THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 88 72 82 69 / 30 30 60 50
FMY 90 73 88 71 / 20 10 40 30
GIF 90 70 85 69 / 60 50 60 50
SRQ 86 74 83 70 / 10 30 60 50
BKV 89 67 82 64 / 50 50 70 60
SPG 87 74 82 70 / 20 30 60 50
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MID TERM/LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1201 AM EDT THU MAY 1 2014
.SYNOPSIS...
THE SLOW MOVING FRONTAL SYSTEM WILL REMAIN IN THE FORECAST AREA
INTO THURSDAY. THE FRONT WILL BE NEAR THE COAST THURSDAY NIGHT AND
FRIDAY. DEEPER MOISTURE AHEAD OF THE FRONT HAS SHIFTED EAST OF THE
FORECAST AREA.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THE SLOW MOVING FRONT WILL BE IN THE FORECAST AREA TONIGHT.
LATEST RAP AND LAPS ANALYSIS INDICATE WEAK MID LEVEL CAP AND HIGH
LFC. HRRR SHOWS LIMITED COVERAGE AS FRONT MOVES INTO THE AREA.
UPSTREAM RADAR ANALYSIS NOT IMPRESSIVE. CONVERGENCE ASSOCIATED
WITH THE FRONT MAY SUPPORT SHOWERS AND THUNDERSTORMS BUT EXPECT
LITTLE COVERAGE WITH DEEPER MOISTURE EAST OF THE REGION.
CLOUDINESS AND MIXING WILL HOLD UP TEMPERATURES. A COOL BIAS NOTED
IN MOS BUT WEAK COLD ADVECTION DEVELOPING AFTER 09Z. EXPECT LOWS
MAINLY IN THE MIDDLE TO UPPER 60S.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
THE NAM AND GFS KEEP THE FRONT IN THE FORECAST AREA THURSDAY BUT
DEEPER MOISTURE IS FARTHER EAST. THE GFS AND NAM MOS SUPPORT CHANCE
POPS...MAINLY IN THE EAST SECTION. THE MODELS INDICATE A LITTLE
MORE DRYING THURSDAY NIGHT...BUT SOME INCREASE IN MOISTURE
ASSOCIATED WITH A WAVE ALONG THE STALLED FRONT FRIDAY. THE
GUIDANCE CONSENSUS SUPPORTS CHANCE POPS IN THE EAST PART FRIDAY
INTO FRIDAY NIGHT. USED THE GUIDANCE CONSENSUS FOR THE TEMPERATURE
FORECAST.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE GFS AND ECMWF INDICATE A DRY PATTERN DURING THE MEDIUM-RANGE
PERIOD. MOISTURE ASSOCIATED WITH THE OFFSHORE FRONT APPEARS TO BE
EAST OF THE AREA EARLY IN THE PERIOD. THE MODELS DISPLAY MOISTURE
ASSOCIATED WITH ANOTHER FRONT STAYING MAINLY NORTH OF THE AREA
LATER IN THE PERIOD. THE GFS ENSEMBLE MEAN POPS ARE LESS THAN 10
PERCENT THROUGH THE PERIOD.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
MAINLY JUST HIGH LEVEL CLOUDINESS...WITH NO RETURNS ON RADAR...OVER
OUR FORECAST AREA CURRENTLY. FRONTAL BOUNDARY CURRENTLY STRETCHED TO
OUR WEST...ACROSS E TENN AND NW GA TO THE GULF COAST. SCATTERED
SHOWER ACTIVITY ALONG THE FRONT. THE FRONT IS EXPECTED TO SLOWLY
MOVE INTO OUR FA DURING THE OVERNIGHT HOURS...PASSING THROUGH THE
TERMINALS THURSDAY MORNING. A MOIST SW FLOW AHEAD OF THE FRONT ALONG
WITH FRONTAL CONVERGENCE AND DIURNAL COOLING MAY PROMOTE MVFR CIGS
AND A FEW SHOWERS AT THE TERMINALS LATE TONIGHT. THE FRONT IS
EXPECTED TO MOVE EAST OF THE TERMINALS BY THURSDAY LATE MORNING TO
MIDDAY...THOUGH THE SLOW MOVING FRONT COULD STILL BE CLOSE ENOUGH TO
OGB TO PROVIDE A CHANCE OF SHRA OR PSBL THUNDER THERE THRU EARLY
AFTN.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1200 AM CDT THU MAY 1 2014
.DISCUSSION...
06Z TAF ISSUANCE.
&&
.AVIATION...
SHRA ENDING FROM W TO E OVER THE COASTAL WATERS ACROSS THIS
EVENING. THUS...ONLY MID/HIGH LEVEL CLOUDINESS EXPECTED FOR S SITES
WITH VFR EXPECTED. NNW WINDS 6-8 KTS THIS EVENING WILL DIMINISH A
BIT TOWARDS DAYBREAK...THEN INCREASE FROM THE NNE ~10-12 KTS WITH
GUSTS TO 20 KTS AFTER 15Z THU. MAINLY NE WINDS 5 KTS OR LESS
EXPECTED AFTER 00Z.
DML
&&
.PREV DISCUSSION... /ISSUED 942 PM CDT WED APR 30 2014/
UPDATE...
CONTINUED CHANCE POPS OVER THE SOUTHEASTERN HALF OF THE COASTAL
WATERS AS ELEVATED OVER-RUNNING SHOWERS AND ISOLATED STORMS
CONTINUE...WITH ACTIVITY GRADUALLY DECREASING AND PUSHING FURTHER
TO THE SOUTHEAST. SOME OF THIS ACTIVITY...MAINLY A FEW SHOWERS
WITH VERY LIGHT RAIN OR SPRINKLES...MAY SKIRT PORTIONS OF SAINT
MARY PARISH AND LOWER SAINT MARTIN PARISH UNTIL SHORTLY AFTER
MIDNIGHT. REMAINDER OF THE FORECAST REMAINS UNCHANGED.
RUA
PREV DISCUSSION... /ISSUED 601 PM CDT WED APR 30 2014/
DISCUSSION...
00Z TAF ISSUANCE.
AVIATION...
WSW TO ENE STREAMING SHRA OVER THE COASTAL WATERS ACROSS LOWER
ACADIANA EXPECTED TO REMAIN S OF LFT/ARA THIS EVENING AND OVERNIGHT.
THUS...ONLY MID LEVEL CLOUDINESS EXPECTED FOR S SITES WITH VFR
EXPECTED. NNW WINDS 6-8 KTS THIS EVENING WILL DIMINISH A BIT
TOWARDS DAYBREAK...THEN INCREASE FROM THE NNE ~10-12 KTS WITH
GUSTS TO 20 KTS AFTER 15Z THU.
DML
PREV DISCUSSION... /ISSUED 335 PM CDT WED APR 30 2014/
DISCUSSION...
UPPER AIR ANALYSIS INDICATES LARGE SPRAWLING CYCLONE CENTERED OVER
THE MIDWEST THIS AFTERNOON. COLD FRONT HAS NOW PAST THE COASTAL
WATERS WITH TEMPERATURES OVER THE AREA THIS AFTERNOON IN THE LOWER
70S TO UPPER 60S. RADAR IS CONTINUING TO SHOW SOME
SHOWERS/SPRINKLE OVER THE COASTAL WATER INTO SOUTH CENTRAL
LOUISIANA WITH A FEW EMBEDDED THUNDERSTORMS JUST BEYOND THE
COASTAL WATERS. THIS ACTIVITY IS LIKELY THE RESULT OF JET STREAK
AND ASSOCIATED SHORT WAVE IN THE SOUTHERN BRANCH OF THE JET
STREAM.
GUIDANCE HAS BEEN POOR WITH THE ELEVATED SHOWERS AND THUNDERSTORMS
OVER THE COASTAL WATERS TODAY...HOWEVER THE LAST SEVERAL RUNS OF
THE HRRR HAS PICKED UP ON IT AND CONTINUES TO SHOW ACTIVITY ACROSS
THE COASTAL WATERS AND WITH SOME COMING ONSHORE IN IBERIA...ST.
MARY AND ST. MARTIN PARISHES FOR THE NEXT FEW HOURS BEFORE IT
FINALLY DISSIPATES/MOVES EAST.
WILL MAINTAIN SOME MENTIONABLE POPS IN THE SOUTHEAST COASTAL
WATERS FOR THE NEXT 24-36 HOURS AS THIS AREA REMAINS IN FAVORABLE
AREA OF THE JET AND IMPULSES RIDING ACROSS IN IT. OTHERWISE AREAS
INLAND LOOK DRY THROUGH THE REMAINDER OF THE FORECAST.
COOL TEMPERATURES TONIGHT...ESPECIALLY INTERIOR SOUTHEAST TEXAS
AND WEST CENTRAL LOUISIANA WITH TEMPERATURES GETTING INTO 45 TO 50
RANGE! TEMPERATURES WILL GRADUALLY WARM THROUGH THE PERIOD BACK TO
NEAR SEASONAL NORMALS BY THE WEEKEND.
THE ONLY OTHER CHANGE WAS TO ADD SCEC TO THE COASTAL WATERS
TONIGHT AND FRIDAY MORNING AS WINDS WILL INCREASE AGAIN OVERNIGHT
AS THE BOUNDARY LAYER DESTABILIZES OVER THE RELATIVELY WARMER GULF
WATERS.
27
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 51 75 53 78 56 / 10 10 10 10 10
KBPT 53 76 55 78 57 / 10 10 10 10 10
KAEX 48 73 51 77 51 / 0 0 10 10 10
KLFT 52 73 55 76 56 / 10 10 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION THROUGH THURSDAY AFTERNOON FOR THE
FOLLOWING ZONES: WATERS FROM INTRACOASTAL CITY TO CAMERON
LA FROM 20 TO 60 NM...WATERS FROM CAMERON LA TO HIGH ISLAND
TX FROM 20 TO 60 NM...WATERS FROM LOWER ATCHAFALAYA RIVER
TO INTRACOASTAL CITY LA FROM 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
442 PM EDT THU MAY 1 2014
.SYNOPSIS...
AN UPPER LEVEL SYSTEM BRINGS A CHANCE OF SHOWERS TO THE REGION
OVER THE WEEKEND. LOW PRESSURE AND A TRAILING COLD FRONT WILL
APPROACH FROM THE WEST SATURDAY THEN CROSS THE REGION SUNDAY
BRINGING AN INCREASING CHANCE OF RAIN. THE SYSTEM STALLS OVER THE
MARITIMES ON MONDAY PRODUCING ISOLATED TO SCATTERED SHOWERS ACROSS
THE REGION. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST TUESDAY
AND WEDNESDAY WITH IMPROVING WEATHER.
&&
.NEAR TERM /TONIGHT/...
445PM UPDATE...
HAVE MADE SOME UPDATES TO ACCOUNT FOR OBSERVED CLOUD COVER AND
PRECIPITATION TRENDS. SHOULD SEE A BROKEN LINE OF SHOWERS ENTER
NEW HAMPSHIRE AROUND 7 OR 8 PM. HRRR INDICATES THIS LINE WILL
CONTINUE TO BREAK UP AS IT MOVES ACROSS NEW HAMPSHIRE AND MAINE
THIS EVENING. STILL A CHANCE OF FOG LATER THIS EVENING.
ORIGINAL DISCUSSION...
JUST A FEW SHOWERS REMAIN OVER EASTERN MAINE ASSOCIATED WITH THE
WARM FRONT AS IT LIFTS THROUGH DOWNEAST MAINE AND TOWARDS THE
CANADIAN MARITIMES. FINALLY SEEING SOME BREAKS IN CLOUDS OVER NH
AND WESTERN MAINE ALLOWING TEMPERATURES TO REACH THE LOWER 60S IN
A FEW SPOTS. STRATUS AND FOG WILL CREEP BACK AFTER DARK ONCE AGAIN
HOWEVER AS INVERSION DEVELOPS ONCE AGAIN. TEMPERATURES SHOULD BE
PRETTY WELL INSULATED IN THE LOWER TO MID 40S.
MODELS ARE STILL SHOWING MORE SHOWERS TONIGHT AND OVERNIGHT AS
ADDITIONAL UPPER LEVEL SUPPORT MOVES THROUGH. ONLY EXPECTING A
TENTH OR SO OF ADDITIONAL QPF WITH THIS ACTIVITY WITH THE
MOUNTAINS BEING THE BEST BET.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
FAST MOVING SHORT WAVE WILL CROSS THE REGION TOMORROW IN SW FLOW
ALOFT. THIS WILL KEEP CLOUDS AND SOME SHOWERS IN THE AREA...
HOWEVER AM EXPECTING ANY VERY LOW CLOUDS TO LIFT AS WEST WINDS
BECOME GUSTY AFTER DAYBREAK. WARM 850MB TEMPERATURES AND WSW WINDS
WILL WARM TEMPERATURES INTO THE 50S AND 60S AND EXPECT THE
WARMEST READINGS IN SOUTHERN SECTIONS. TOMORROW NIGHT WE WILL SEE
CLEARING ESPECIALLY ALONG THE COASTAL PLAIN WITH TEMPERATURES
DROPPING INTO THE 30S AND 40S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A WARM DAY SATURDAY WITH A SW FLOW IN ADVANCE OF THE UPPER TROUGH
OVER THE GREAT LAKES THAT DEEPENS AND EVOLVES INTO A CLOSED
UPPER LOW SYSTEM AS IT TRACKS EAST TOWARD NEW ENGLAND LATE
SATURDAY INTO SUNDAY. THE UPPER LOW SETTLES OVER NEW ENGLAND BY
LATE SUNDAY AND INTO MONDAY WITH A COLD POOL OF AIR ALOFT WITH A
CYCLONIC FLOW OVER THE AREA. THIS ALL MEANS SATURDAY WILL BE WARM
WITH TEMPERATURES WELL INTO THE 60S BUT A RETURN TO MUCH COOLER
TEMPERATURES FOR SUNDAY AND EARLY NEXT WEEK. AN UNSETTLED PATTERN
CAN BE EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
BY TUESDAY A DRY NW FLOW DEVELOPS AND A SLOW RETURN TO WARMER
TEMPERATURES WITH FAIR AMOUNT OF SUNSHINE THAT WILL CONTINUE THRU
MIDWEEK AS A SURFACE/UPPER RIDGE BUILDS EAST ACROSS THE NORTHEASTERN
UNITED STATES.
USED A BLEND OF THE MAV/MET GUIDANCE FOR 4TH/5TH PERIODS AND THEN
STAYED CLOSE TO THE SUPERBLEND FOR POPS AND TEMPERATURES THRU THE
OUTLOOK PERIOD.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
SHORT TERM...CURRENT CLEARING WILL LAST UNTIL DARK AND AS SOON AS
INVERSION IS ESTABLISHED AGAIN EXPECT 1/4SM/VV001 AT ALL
TERMINALS. MVFR TO LIFR CONDITIONS WILL STAY OR DROP TO LIFR
WITH PLENTY OF LOW LEVEL/GROUND MOISTURE AVAILABLE FOR STRATUS AND
FOG TONIGHT. IMPROVEMENT TO VFR WILL OCCUR AROUND 10-12Z WITH AN
INCREASE IN GUSTY WEST WINDS.
LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...VFR CONDITIONS SATURDAY
LOWERING TO MVFR/IFR LATE SATURDAY THRU MONDAY. CONDITIONS IMPROVE
TO VFR TUESDAY.
&&
.MARINE...
SHORT TERM...SMALL CRAFT ADVISORY WAS CONVERTED TO JUST ADVISORY
FOR SEAS AS WIND GUSTS HAVE DIMINISHED. SOUTHERN OUTER ZONE WILL
DROP BELOW CRITERIA AFTER DAYBREAK FRIDAY AND WILL BE ALLOWED TO
DROP OUT OF THE ADVISORY WHILE THE OTHER LOCATIONS CONTINUE TO SEE
HIGH SEAS.
LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...WINDS AND SEAS MOSTLY
BELOW SCA LEVELS UNTIL NW WIND GUSTS AND SEAS REACH MINIMAL SCA
LEVELS OVER THE OPEN WATERS SUNDAY NIGHT AND MONDAY BEHIND THE
DEPARTING AND STRENGTHENING LOW PRESSURE SYSTEM.
&&
.FIRE WEATHER...
UNSETTLED PERIOD SHOULD KEEP FIRE WEATHER CONCERNS LOW. WILL BE
WARM THIS FRIDAY IN SOUTHERN AREAS WITH A SW WIND...BUT EXPECT
MINIMUM RH VALUES ABOVE 35% ALL AREAS. EXPECT MORE RAIN TONIGHT
AND TOMORROW.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT FRIDAY
FOR ANZ151-153-154.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 PM EDT FRIDAY
FOR ANZ150-152.
&&
$$
NEAR TERM UPDATE... KIMBLE
SHORT TERM... HANES
LONG TERM... MARINE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1219 AM CDT THU MAY 1 2014
.UPDATE...
ISSUED AT 1054 PM CDT WED APR 30 2014
SENT AN ENHANCED SHORT-TERM FCST /ESTF/ UPDATE AT 1049 PM...
PRIMARILY TO BRUSH UP TEMP/DEWPOINT/SKY/WIND TRENDS. THE MOST
SIGNIFICANT CHANGE WAS TO LOWER THE WINDS.
OVERALL IT APPEARS AREAS E OF HWY 281 WILL REMAIN MOSTLY CLOUDY
OVERNIGHT...WHILE AREAS TO THE W WILL BE MOSTLY CLEAR. THIS TOO
HAS BEEN REFLECTED BETTER IN THE FCST USING THE RAP 13KM CLOUD
COVER.
UPDATE ISSUED AT 703 PM CDT WED APR 30 2014
DECREASING DIABATIC HEATING AND A RESULTANT DECREASE IN BOUNDARY
LAYER DEPTH AND MIXING HAS ALLOWED THE LOWER TROPOSPHERIC WIND
FIELD TO DECREASE IN INTENSITY THROUGH THE PAST FEW HOURS.
GUIDANCE SUGGESTS THIS IS A TREND WHICH WILL CONTINUE THROUGH THE
REST OF TONIGHT. AS A RESULT...THE WIND ADVISORY WAS ALLOWED TO
EXPIRE AT 00Z.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 344 PM CDT WED APR 30 2014
THE MAIN FOCUS DURING THE SHORT TERM PERIODS IS ON WINDS...ALONG
WITH AN OUTSIDE CHC FOR SPRINKLES/RAIN SHOWERS. THE PATTERN ALOFT
CONTINUED TO FEATURE A BLOCKING PATTERN WITH RIDGING ALONG THE
WESTERN AND EASTERN CONUS...AND A DEEP TROUGH ACROSS THE INTERIOR
CONUS WITH THE CENTER OF THE UPPER LOW SITUATED IN IOWA. UNDER THE
INFLUENCE OF THE LOW...CLOUDY...WINDY AND UNSEASONABLY COOL
TEMPERATURES PERSIST ACROSS OUR REGION.
WE CURRENTLY HAVE A WIND ADVISORY IN EFFECT ACROSS OUR CWA EXCEPT
FOR OUR FAR SOUTHEAST AREAS. IN A TIGHT PRESSURE
GRADIENT...NORTHWEST WINDS AVERAGE 25 TO 35 MPH WITH GUSTS TO 45
MPH. WIND SPEEDS WILL CONTINUE TO REMAIN STRONG THRU LATE AFTN
BEFORE SUBSIDING BELOW ADVISORY CRITERIA THIS EVENING. THE WINDS
WILL REMAIN STEADY DURING THE OVERNIGHT PERIODS WHICH WILL INHIBIT
THE FORMATION OF FROST AS TEMPERATURES COOL TO THE MID 30S FOR
LOWS.
A JET STREAK AND SHORTWAVE ENERGY ROTATE AROUND THE UPPER LOW
ACROSS EAST CENTRAL/EASTERN NEBRASKA TONIGHT WITH ANOTHER SURGE
OF LOW CLOUDS ADVECTING INTO OUR NORTHERN/EASTERN AREAS AND
BRINGING AN OUTSIDE CHANCE FOR ISOLATED RAIN SHOWERS OR SPRINKLES.
HAVE OPTED TO CARRY SPRINKLES FOR OUR EASTERN ZONES TONIGHT AS
THIS WAVE MOVES THRU.
ON THURSDAY...BREEZY AND COOL CONDITIONS REMAIN BUT WE TREND
TOWARD IMPROVING WEATHER CONDITIONS FOR THE FIRST OF MAY. TEMPS
WILL BE A FEW DEGREES WARMER AND WINDS WILL BE ABOUT 5 TO 10 MPH
WEAKER THAN TODAY...AS THE UPPER LOW PRESSURE SYSTEM WILL FINALLY
BE LIFTING OUT TOWARD THE GREAT LAKES REGION AND HEIGHTS RISE
BEHIND THE DEPARTING SYSTEM AS THE WESTERN RIDGE BUILDS EASTWARD.
THE PRESSURE GRADIENT REMAINS STRONGEST DURING THE MORNING AND
RELAXES IN THE AFTERNOON WHICH WILL LEAD TO A GRADUAL REPRIEVE
FROM THE WINDY CONDITIONS. HAVE TARGETED HIGH TEMPS IN THE UPPER
50S TO NEAR 60 DEGREES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 344 PM CDT WED APR 30 2014
PRIMARY FORECAST CONCERNS THROUGH THE LONG TERM
PERIOD ARE TEMPERATURES...AND VERY END OF THE PERIOD PRECIPITATION
CHANCES.
MODELS IN GOOD AGREEMENT AT THE START OF THE FORECAST
PERIOD...SHOWING THE MAIN UPPER LEVEL TROUGH AXIS /EXTENDING FROM
LOW PRESSURE OVER ONTARIO/ FINALLY CLEARING THE CWA TO THE
SOUTHEAST DURING THURSDAY EVENING HOURS. THROUGH THE REST OF THE
OVERNIGHT PERIOD...SHARPER NORTHWESTERLY FLOW DEVELOPS IN THE
UPPER LEVELS...AS THE TROUGH SLIDES FURTHER AWAY AND RIDGING
DOMINATES THE WEST COAST. NOT EXPECTING ANY SIGNIFICANT CHANGES IN
THE PATTERN THROUGH THE DAYTIME ON FRIDAY...AND KEPT THINGS DRY.
AT THE SFC...WINDS START THE PERIOD OUT OF THE NW...PRIMARILY
INFLUENCED BY LOW PRESSURE OVER THE GREAT LAKES...BUT BECOME MORE
WESTERLY OVERNIGHT THURSDAY AND INTO FRIDAY AND TAPERING OFF IN
SPEED. STILL A CONCERN FOR THE POTENTIAL FOR FROST THURSDAY
NIGHT...AS THOSE WINDS TAPER OFF...AND MODELS/GUIDANCE CONTINUING
TO SHOW OVERNIGHT LOWS FALLING INTO THE MID 30S...AND WILL KEEP
MENTION GOING IN THE HWO. FOR HIGHS ON FRIDAY...EXPECTING A NICE
WARM UP COMPARED TO THURSDAY...WITH THE DOWNSLOPING COMPONENT TO
INCREASING WINDS DURING THE DAY COMBINED WITH WARMER TEMPS
ALOFT...AND TEMPS FORECAST TO REACH THE LOWER/MID 70S.
LOOKING AT FRIDAY NIGHT AND THROUGH THE UPCOMING WEEKEND...MODELS
SHOWING THAT UPPER LEVEL RIDGING STILL REMAINS A MAIN PLAYER IN
THE PATTERN IMPACTING THE CWA...BUT WITH TIME THE RIDGING
BECOMING LESS AMPLIFIED AS ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM
IS ONTO THE PAC NW COAST. KEPT THE FORECAST DRY THROUGH THE
WEEKEND...BUT CONFIDENCE IN IT REMAINING THAT WAY IS NOT EXTREMELY
HIGH...MAINLY ACROSS THE NRN THIRD OR SO OF THE CWA. LIFT VIA AN
UPPER LEVEL JET STREAK SLIDING SOUTHEAST OUT OF WRN CANADA BETWEEN
LOW PRESSURE OVER CENTRAL CANADA AND THE WRN CONUS RIDGE COULD BE
ENOUGH TO PRODUCE SOME LIGHT PRECIPITATION...MAINLY FRIDAY NIGHT
THROUGH SAT NIGHT...BUT AT THIS POINT MUCH OF THE MODEL SUPPORT
KEEPS IT JUST TO THE NORTH OF THE CWA. LITTLE UNCERTAINTY IN THE
TEMP FORECAST FOR THIS WEEKEND...AS MODELS SHOW SFC LOW PRESSURE
SETTING UP OVER THE KS/CO BORDER...WITH A WARM FRONT DRAPED EAST
NEAR THE NEB/KS STATE LINE. THE EASTERLY WINDS NORTH OF THE FRONT
WILL KEEP SC NEB COOLER WITH HIGHS GENERALLY IN THE 60S/MID
70S...VS NC KS WHICH IS SOUTH OF THE FRONT...WHICH BY SUNDAY COULD
CLIMB UP NEAR 80. JUST GOING TO DEPEND ON WHERE EXACTLY THAT FRONT
SETS UP.
AS WE GET INTO MON THROUGH WEDNESDAY...THE BROAD UPPER LEVEL RIDGE
STARTS PUSHING EAST THROUGH THE CENTRAL PLAINS...AND BY MONDAY
NIGHT MORE SOUTHWESTERLY FLOW IS STARTING TO BUILD IN...AS THE
WEST COAST SYSTEM IS DIGGING FURTHER SOUTH. SOME QUESTION AS WE GO
THROUGH THE REMAINDER OF THE FORECAST PERIOD HOW THIS SYSTEM WILL
EVOLVE AS IT MOVES EAST...WILL IT DIG FURTHER SOUTH INTO THE
DESERT SW/REMAIN A CLOSED SYSTEM LIKE THE GFS SUGGESTS...OR REMAIN
OPEN LONGER...BEFORE BECOMING BETTER ORGANIZED OVER THE NRN
ROCKIES LIKE THE ECMWF. SOME NOTABLE DIFFERENCES TO WORK OUT.
COULD SEE SOME LEAD SHORTWAVE ENERGY AFFECT THE AREA TUES
NIGHT/WED...AND HAVE SOME LOW POPS IN THE FORECAST. AS FAR AS
TEMPS GO...STUCK CLOSE TO ALLBLEND...SHOWING HIGHS INCREASING INTO
THE MID 70S/MID 80S RANGE BY WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z GRI TAF THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1219 AM CDT THU MAY 1 2014
REST OF TONIGHT: VFR WITH SCT V BKN CLOUDS MOSTLY AROUND 7-8K FT.
NW WINDS WERE CURRENTLY GUSTING TO 28 KTS AT 05Z. THIS GUSTINESS
SHOULD CONT FOR ANOTHER 1-3 HRS WHILE GRADUALLY DECREASING. BY 08Z
IT SHOULD BE DONE. CONFIDENCE: HIGH
THU: VFR WITH BKN 7-8K FT CIGS GIVING WAY TO SCT STRATOCU
DEVELOPING AND LIFTING FROM 4-6K FT. NNW WINDS WILL GUST UP TO 34
KTS 13Z-16Z. GUSTINESS WILL CONT INTO THE AFTERNOON...BUT SHOULD
PEAK NO HIGHER THAN 26 KTS. CONFIDENCE: HIGH
THU EVE: ANY STRATOCU WILL DISSIPATE BY 01Z LEAVING VFR SKC. WINDS
DIMINISH TO LESS THAN 10 KTS FROM THE NW. CONFIDENCE: HIGH.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...FAY
LONG TERM...ADO
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1043 PM EDT FRI MAY 2 2014
.SYNOPSIS...
AN IMPULSE ALOFT APPROACHING FROM THE SOUTHWEST PASS THROUGH THE
AREA TONIGHT AND EARLY SATURDAY. SEASONABLE HIGH PRESSURE WILL
BUILD IN THROUGH THE WEEKEND. A COLD FRONT WILL PRESS SOUTHWARD AND
STALL OVER EASTERN NORTH CAROLINA EARLY NEXT WEEK. WARM HIGH
PRESSURE WILL BUILD INTO THE REGION THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1030 PM FRIDAY...THE MAIN SFC BAROCLINIC ZONE JUST OFF THE
CAROLINA COASTS LATE THIS EVENING...WILL FINALLY GET PUSHED
FURTHER OFFSHORE AND AWAY FROM THE NC-SC MAINLAND OVERNIGHT THRU
DAY-TIME SATURDAY. THIS IN RESPONSE TO A POSITIVELY TILT S/W TROF
ALOFT THAT TRACKS ESE...CROSSING THE APPALACHIANS LATER TONIGHT
AND OFF THE CAROLINA COASTS LATE SAT. AS A RESULT...VIA LATEST
VARIOUS MODEL TIME HEIGHT DISPLAYS ACROSS THE FA...CLOUDY SKIES
WILL PREVAIL OVERNIGHT INTO DAYLIGHT SAT. AND WITH JUST ENOUGH
MOISTURE AND UVVS AHEAD OF THE APPROACHING UPPER S/W
TROF...ISOLATED SHOWERS REMAIN POSSIBLE DURING THE PRE-DAWN SAT
HOURS...MAINLY ALONG THE IMMEDIATE COAST AND ADJACENT COASTAL
WATERS. HAVE STAYED CLOSER TO THE PREVIOUS MIN TEMP FORECAST WITH
AN ADJUSTMENT HIER BY 1 TO 3 DEGREES MAINLY CLOSER TO THE COAST
DUE TO CLOUDINESS AND LACK OF ANY ADDITIONAL CAA. IN FACT...THE
IMMEDIATE COAST MAY STAY WELL IN THE 50S TO NEAR 60. WILL MAKE A
FINAL CALL ON COASTAL LOWS PRIOR TO ISSUANCE.
PREVIOUS DISCUSSION...................................
AS OF 3 PM FRIDAY...MOSAIC RADAR BEAMS ARE CATCHING WIDESPREAD
ECHOS ACROSS THE FORECAST AREA...BUT OBSERVED HOURLY RAINFALL
AMOUNTS PAINT A DRIER PICTURE THAN IS PRESENTED GRAPHICALLY BY
THE SUITE OF LOCAL 88 DELTAS. OF INTEREST IS SHORT-WAVE ENERGY
MOVING FROM THE NE GULF INTO GEORGIA THIS AFTERNOON. THIS FEATURE
MAY AID IN STIRRING UPWARD VERTICAL MOTIONS...THROUGH MIDDLE INTO
LATE AFTERNOON. THE MOST SIGNIFICANT RAIN AREA OFFSHORE OF N FL
AND SC APPEARS ON A TRACK THAT WILL REMAIN OFFSHORE OF OUR COUNTY
WARNING AREA.
COMPOSITE/CONSENSUS PCPN FIELDS PULL ALL RAIN OFFSHORE BY 11PM
EXCEPT FOR THE RAP-13...WHICH IS BIT UNSETTLING SINCE BY THEORY
A RAPID UPDATE NEAR-TERM MODEL INGESTS THE LATEST AND GREATEST.
THE RAP GENERATES A FEW SHOWERS IN THE PRE-DAWN HOURS ALONG THE
COAST...APPARENTLY KEYING ON THE POTENT APPEARING VORT CAREENING
INTO WESTERN TN AND WESTERN MS. THIS FEATURE IN FACT DOES IMPART
A SURFACE REFLECTION IN THE FORM OF A MINOR AND SECONDARY COLD
FRONT. WITH THIS IN MIND WILL KEEP ISOLATED SHOWERS AT THE COAST
INTO THE DAYBREAK HOURS. MINIMUMS INTO THE 50S EXPECTED AREA-WIDE
BUT COOLEST INLAND...AS A SECONDARY SURGE OF COOL AIR FILTERS INTO
THE REGION AFTER 8-9 ZULU/4-5 AM.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...A COLD FRONT JUST OFF THE COAST SAT AM WILL
MOVE OUT TO SEA OVER THE WEEKEND AS HIGH PRESSURE RIDGES INTO THE
AREA. ANOTHER COLD FRONT WILL APPROACH FROM THE NORTH SUNDAY NIGHT
AND MOVE INTO THE AREA LATE. AFTER SOME MORNING CLOUDS AND
POSSIBLY A FEW LIGHT SHOWERS EARLY SATURDAY...EXPECT FAIR WEATHER
THROUGH THE WEEKEND. MAX TEMPERATURES AWAY FROM THE BEACHES WILL
BE IN THE MID TO UPPER 70S SATURDAY AND LOW TO MID 80S SUNDAY.
MINS SATURDAY NIGHT WILL BE IN THE LOW TO MID 50S WITH UPPER 50S
TO AROUND 60 EXPECTED SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...OVERALL THE LONG TERM LOOKS PRETTY QUIET. THERE
IS SOME UNCERTAINTY AS TO HOW FAR SOUTH A BACKDOOR COLD FRONT
PROGRESSES EARLY IN THE PERIOD. MODEL GUIDANCE HAS SHIFTED A BIT TO
THE SOUTH AND THE BOUNDARY MAY ENTER NORTHERN ZONES. SOME VERY LOW
POPS HAVE BEEN ADDED AS A RESULT. AS THE PARENT HIGH SHIFTS EASTWARD
OFF THE MID ATLANTIC COAST THIS BOUNDARY WILL MOVE BACK TO THE NORTH
IN A WEAKENING STATE AROUND WEDNESDAY. THE LATTER PART OF THE WEEK
WILL BRING RISING HEIGHTS AS UPPER RIDGE BUILDS AND HIGHEST SFC
PRESSURES OFF THE COAST.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...PRECIP HAS MOVED EAST OF ALL AREA TERMINALS. CEILINGS
ALREADY WELL ABOVE VFR AND WILL CONTINUE TO TREND UPWARD THROUGH THE
EVENING. A WEAK SURFACE PRESSURE FIELD OVER THE AREA WILL KEEP WINDS
ON THE LIGHT AND VARIABLE SIDE OVERNIGHT...BECOMING ESTABLISHED FROM
THE WEST-SOUTHWEST DURING SATURDAY AS HIGH PRESSURE BEGINS TO BUILD
IN FROM THE GULF COAST.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS LATE MONDAY INTO EARLY
TUESDAY ASSOCIATED WITH A STALLED FRONT TO OUR NORTH. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM FRIDAY...CURRENT SFC PRESSURE PATTERN RATHER DIFFUSE
AFTER THE 1ST COLD FRONTAL PASSAGE EARLIER TODAY. THIS WILL MAKE
FORECASTING DOMINATE WIND DIRECTIONS A BIT TRICKY FOR THE
OVERNIGHT PERIOD. HAVE IDENTIFIED SW-W AS THE DOMINATE DIRECTIONS.
WITH THE SFC PG REMAINING RATHER LOOSE OVERNIGHT...WIND SPEEDS WILL
LIKELY HOVER AROUND 10 KT. SIGNIFICANT SEAS WILL RUN 2 TO
OCCASIONALLY 3 FT...AND MAINLY BE DOMINATED BY A SE-SSE PSEUDO
GROUND SWELL RUNNING 1.0 TO 2.0 FT...WITH THE REMAINING
SIGNIFICANT SEAS MAKE-UP CONSISTING OF LOCALLY PRODUCED WIND
DRIVEN WAVES. WAVEWATCH3 AND LOCAL SWAN OUTPUT CONCUR.
PREVIOUS DISCUSSION...........................................
AS OF 3 PM FRIDAY...NO ADVISORIES OR EXERCISE CAUTION HEADLINES
WILL BE NEEDED OVERNIGHT. WINDS WILL BE CHANGEABLE BUT NOT STRONG
AS A SECONDARY BUT WEAK COLD FRONT PASSES ACROSS THE COAST INTO
EARLY SATURDAY JUST PRIOR TO OR AROUND DAYBREAK. SEAS MAINLY 2-3
FEET IN A MIX OF 2-3 FT SSE WAVES EVERY 6-8 SECONDS AND A LIGHT
CHOP. LIGHT S-SW WINDS TONIGHT WILL PREVAIL...FOLLOWED BY A WIND-
SHIFT TO THE NW INTO FIRST LIGHT OF SATURDAY AS THE FRONT MOVES
THROUGH. NO TSTMS EXPECTED OVER THE INSHORE WATERS...BUT A FEW
STORMS MAY LIGHT UP THE GULF STREAM INTO EARLY SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...LIGHT WEST TO SOUTHWEST FLOW AROUND 10 KT IS
EXPECTED SATURDAY AND SATURDAY NIGHT BEFORE BECOMING SOLIDLY SW
SUNDAY AND INCREASING TO 15 KT BY AFTERNOON AND CONTINUING INTO
SUNDAY NIGHT. WINDS WILL BECOME MORE WESTERLY NORTHERN WATERS LATE
AS A FRONT APPROACHES FROM THE NORTH. SEAS OF 2 TO 3 FT EARLY
SATURDAY WILL SUBSIDE TO 2 FT OR LESS BY SATURDAY EVENING AND
CONTINUE INTO SUNDAY BEFORE BUILDING TO 2 TO 3 FT BY SUNDAY NIGHT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...WITH A BACKDOOR COLD FRONT STALLED CLOSE TO IF
NOT ACROSS THE REGION FOR MOST OF THE PERIOD WINDS AND SEAS WILL
BOTH BE RATHER MINIMAL. THERE IS SOME UNCERTAINTY REGARDING HOW FAR
SOUTH THE BOUNDARY WILL SAG HOWEVER AND THIS TRANSLATES TO SOME
POSSIBLE ERROR IN WIND FCST OVER MAINLY NRN ZONES. SRN ZONES SHOULD
REMAIN ON THE SOUTH SIDE OF THE BOUNDARY AND THUS KEEP A
PREDOMINANTLY SOUTHWESTERN FLOW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RAN
NEAR TERM...DCH/MJC
SHORT TERM...RAN
LONG TERM...MBB
AVIATION...CRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
820 PM EDT FRI MAY 2 2014
.SYNOPSIS...
AN IMPULSE ALOFT APPROACHING FROM THE SOUTHWEST PASS THROUGH THE
AREA TONIGHT AND EARLY SATURDAY. SEASONABLE HIGH PRESSURE WILL
BUILD IN THROUGH THE WEEKEND. A COLD FRONT WILL PRESS SOUTHWARD AND
STALL OVER EASTERN NORTH CAROLINA EARLY NEXT WEEK. WARM HIGH
PRESSURE WILL BUILD INTO THE REGION THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 730 PM FRIDAY...THE MAIN BAROCLINIC ZONE JUST OFF THE
CAROLINA COASTS THIS EVENING...WILL FINALLY GET PUSHED FURTHER
OFFSHORE AND AWAY FROM THE NC-SC MAINLAND BY DAYBREAK SATURDAY.
THIS IN RESPONSE TO A POSITIVELY TILT S/W TROF ALOFT THAT TRACKS
ESE...CROSSING THE APPALACHIANS LATER TONIGHT AND OFF THE CAROLINA
COASTS LATE SAT. AS A RESULT...VIA LATEST MODEL TIME HEIGHT
DISPLAYS ACROSS THE FA...CLOUDY SKIES TO PREVAIL OVERNIGHT. AND
WITH JUST ENOUGH MOISTURE AND UVVS AHEAD OF THE APPROACHING
UPPER S/W TROF...ISOLATED SHOWERS REMAIN POSSIBLE DURING THE PRE-
DAWN SAT HOURS MAINLY ALONG THE IMMEDIATE COAST AND ADJACENT
COASTAL WATERS. HAVE STAYED CLOSER TO THE PREVIOUS MIN FORECAST
WITH AN ADJUSTMENT HIER BY 1 TO 3 DEGREES MAINLY CLOSER TO THE
COAST.
PREVIOUS DISCUSSION..............................................
AS OF 3 PM FRIDAY...MOSAIC RADAR BEAMS ARE CATCHING WIDESPREAD
ECHOS ACROSS THE FORECAST AREA...BUT OBSERVED HOURLY RAINFALL
AMOUNTS PAINT A DRIER PICTURE THAN IS PRESENTED GRAPHICALLY BY
THE SUITE OF LOCAL 88 DELTAS. OF INTEREST IS SHORT-WAVE ENERGY
MOVING FROM THE NE GULF INTO GEORGIA THIS AFTERNOON. THIS FEATURE
MAY AID IN STIRRING UPWARD VERTICAL MOTIONS...THROUGH MIDDLE INTO
LATE AFTERNOON. THE MOST SIGNIFICANT RAIN AREA OFFSHORE OF N FL
AND SC APPEARS ON A TRACK THAT WILL REMAIN OFFSHORE OF OUR COUNTY
WARNING AREA.
COMPOSITE/CONSENSUS PCPN FIELDS PULL ALL RAIN OFFSHORE BY 11PM
EXCEPT FOR THE RAP-13...WHICH IS BIT UNSETTLING SINCE BY THEORY
A RAPID UPDATE NEAR-TERM MODEL INGESTS THE LATEST AND GREATEST.
THE RAP GENERATES A FEW SHOWERS IN THE PRE-DAWN HOURS ALONG THE
COAST...APPARENTLY KEYING ON THE POTENT APPEARING VORT CAREENING
INTO WESTERN TN AND WESTERN MS. THIS FEATURE IN FACT DOES IMPART
A SURFACE REFLECTION IN THE FORM OF A MINOR AND SECONDARY COLD
FRONT. WITH THIS IN MIND WILL KEEP ISOLATED SHOWERS AT THE COAST
INTO THE DAYBREAK HOURS. MINIMUMS INTO THE 50S EXPECTED AREA-WIDE
BUT COOLEST INLAND...AS A SECONDARY SURGE OF COOL AIR FILTERS INTO
THE REGION AFTER 8-9 ZULU/4-5 AM.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...A COLD FRONT JUST OFF THE COAST SAT AM WILL MOVE
OUT TO SEA OVER THE WEEKEND AS HIGH PRESSURE RIDGES INTO THE AREA.
ANOTHER COLD FRONT WILL APPROACH FROM THE NORTH SUNDAY NIGHT AND
MOVE INTO THE AREA LATE. AFTER SOME MORNING CLOUDS AND POSSIBLY A
FEW LIGHT SHOWERS EARLY SATURDAY...EXPECT FAIR WEATHER THROUGH THE
WEEKEND. MAX TEMPERATURES AWAY FROM THE BEACHES WILL BE IN THE MID
TO UPPER 70S SATURDAY AND LOW TO MID 80S SUNDAY. MINS SATURDAY
NIGHT WILL BE IN THE LOW TO MID 50S WITH UPPER 50S TO AROUND 60
EXPECTED SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...OVERALL THE LONG TERM LOOKS PRETTY QUIET. THERE
IS SOME UNCERTAINTY AS TO HOW FAR SOUTH A BACKDOOR COLD FRONT
PROGRESSES EARLY IN THE PERIOD. MODEL GUIDANCE HAS SHIFTED A BIT TO
THE SOUTH AND THE BOUNDARY MAY ENTER NORTHERN ZONES. SOME VERY LOW
POPS HAVE BEEN ADDED AS A RESULT. AS THE PARENT HIGH SHIFTS EASTWARD
OFF THE MID ATLANTIC COAST THIS BOUNDARY WILL MOVE BACK TO THE NORTH
IN A WEAKENING STATE AROUND WEDNESDAY. THE LATTER PART OF THE WEEK
WILL BRING RISING HEIGHTS AS UPPER RIDGE BUILDS AND HIGHEST SFC
PRESSURES OFF THE COAST.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...PRECIP HAS MOVED EAST OF ALL AREA TERMINALS. CEILINGS
ALREADY WELL ABOVE VFR AND WILL CONTINUE TO TREND UPWARD THROUGH THE
EVENING. A WEAK SURFACE PRESSURE FIELD OVER THE AREA WILL KEEP WINDS
ON THE LIGHT AND VARIABLE SIDE OVERNIGHT...BECOMING ESTABLISHED FROM
THE WEST-SOUTHWEST DURING SATURDAY AS HIGH PRESSURE BEGINS TO BUILD
IN FROM THE GULF COAST.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS LATE MONDAY INTO EARLY
TUESDAY ASSOCIATED WITH A STALLED FRONT TO OUR NORTH. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 745 PM FRIDAY...CURRENT SFC PRESSURE PATTERN RATHER DIFFUSE
AFTER THE 1ST COLD FRONTAL PASSAGE EARLIER TODAY. THIS MAKING
DOMINATE WIND DIRECTIONS A BIT TRICKY TO PREDICT FOR THE
OVERNIGHT. HAVE IDENTIFIED SW-W AS THE DOMINATE DIRECTIONS.
THE SFC PG WILL REMAIN RATHER LOOSE RESULTING WITH WIND SPEEDS
AROUND 10 KT. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...AND MAINLY
BE DOMINATED BY A SE-S SWELL RUNNING 1.5 TO 2.5 FT. WAVEWATCH3 AND
LOCAL SWAN OUTPUT CONCUR.
PREVIOUS DISCUSSION.............................................
AS OF 3 PM FRIDAY...NO ADVISORIES OR EXERCISE CAUTION HEADLINES
WILL BE NEEDED OVERNIGHT. WINDS WILL BE CHANGEABLE BUT NOT STRONG
AS A SECONDARY BUT WEAK COLD FRONT PASSES ACROSS THE COAST INTO
EARLY SATURDAY JUST PRIOR TO OR AROUND DAYBREAK. SEAS MAINLY 2-3
FEET IN A MIX OF 2-3 FT SSE WAVES EVERY 6-8 SECONDS AND A LIGHT
CHOP. LIGHT S-SW WINDS TONIGHT WILL PREVAIL...FOLLOWED BY A WIND-
SHIFT TO THE NW INTO FIRST LIGHT OF SATURDAY AS THE FRONT MOVES
THROUGH. NO TSTMS EXPECTED OVER THE INSHORE WATERS...BUT A FEW
STORMS MAY LIGHT UP THE GULF STREAM INTO EARLY SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...LIGHT WEST TO SOUTHWEST FLOW AROUND 10 KT IS
EXPECTED SATURDAY AND SATURDAY NIGHT BEFORE BECOMING SOLIDLY SW
SUNDAY AND INCREASING TO 15 KT BY AFTERNOON AND CONTINUING INTO
SUNDAY NIGHT. WINDS WILL BECOME MORE WESTERLY NORTHERN WATERS LATE
AS A FRONT APPROACHES FROM THE NORTH. SEAS OF 2 TO 3 FT EARLY
SATURDAY WILL SUBSIDE TO 2 FT OR LESS BY SATURDAY EVENING AND
CONTINUE INTO SUNDAY BEFORE BUILDING TO 2 TO 3 FT BY SUNDAY NIGHT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...WITH A BACKDOOR COLD FRONT STALLED CLOSE TO IF
NOT ACROSS THE REGION FOR MOST OF THE PERIOD WINDS AND SEAS WILL
BOTH BE RATHER MINIMAL. THERE IS SOME UNCERTAINTY REGARDING HOW FAR
SOUTH THE BOUNDARY WILL SAG HOWEVER AND THIS TRANSLATES TO SOME
POSSIBLE ERROR IN WIND FCST OVER MAINLY NRN ZONES. SRN ZONES SHOULD
REMAIN ON THE SOUTH SIDE OF THE BOUNDARY AND THUS KEEP A
PREDOMINANTLY SOUTHWESTERN FLOW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/MJC
SHORT TERM...RAN
LONG TERM...MBB
AVIATION...CRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
737 PM EDT FRI MAY 2 2014
.SYNOPSIS...
AN IMPULSE ALOFT APPROACHING FROM THE SOUTHWEST PASS THROUGH THE
AREA TONIGHT AND EARLY SATURDAY. SEASONABLE HIGH PRESSURE WILL
BUILD IN THROUGH THE WEEKEND. A COLD FRONT WILL PRESS SOUTHWARD AND
STALL OVER EASTERN NORTH CAROLINA EARLY NEXT WEEK. WARM HIGH
PRESSURE WILL BUILD INTO THE REGION THROUGH THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM FRIDAY...MOSAIC RADAR BEAMS ARE CATCHING WIDESPREAD
ECHOS ACROSS THE FORECAST AREA...BUT OBSERVED HOURLY RAINFALL
AMOUNTS PAINT A DRIER PICTURE THAN IS PRESENTED GRAPHICALLY BY
THE SUITE OF LOCAL 88 DELTAS. OF INTEREST IS SHORT-WAVE ENERGY
MOVING FROM THE NE GULF INTO GEORGIA THIS AFTERNOON. THIS FEATURE
MAY AID IN STIRRING UPWARD VERTICAL MOTIONS...THROUGH MIDDLE INTO
LATE AFTERNOON. THE MOST SIGNIFICANT RAIN AREA OFFSHORE OF N FL
AND SC APPEARS ON A TRACK THAT WILL REMAIN OFFSHORE OF OUR COUNTY
WARNING AREA.
COMPOSITE/CONSENSUS PCPN FIELDS PULL ALL RAIN OFFSHORE BY 11PM
EXCEPT FOR THE RAP-13...WHICH IS BIT UNSETTLING SINCE BY THEORY
A RAPID UPDATE NEAR-TERM MODEL INGESTS THE LATEST AND GREATEST.
THE RAP GENERATES A FEW SHOWERS IN THE PRE-DAWN HOURS ALONG THE
COAST...APPARENTLY KEYING ON THE POTENT APPEARING VORT CAREENING
INTO WESTERN TN AND WESTERN MS. THIS FEATURE IN FACT DOES IMPART
A SURFACE REFLECTION IN THE FORM OF A MINOR AND SECONDARY COLD
FRONT. WITH THIS IN MIND WILL KEEP ISOLATED SHOWERS AT THE COAST
INTO THE DAYBREAK HOURS. MINIMUMS INTO THE 50S EXPECTED AREA-WIDE
BUT COOLEST INLAND...AS A SECONDARY SURGE OF COOL AIR FILTERS INTO
THE REGION AFTER 8-9 ZULU/4-5 AM.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...A COLD FRONT JUST OFF THE COAST SAT AM WILL MOVE
OUT TO SEA OVER THE WEEKEND AS HIGH PRESSURE RIDGES INTO THE AREA.
ANOTHER COLD FRONT WILL APPROACH FROM THE NORTH SUNDAY NIGHT AND
MOVE INTO THE AREA LATE. AFTER SOME MORNING CLOUDS AND POSSIBLY A
FEW LIGHT SHOWERS EARLY SATURDAY...EXPECT FAIR WEATHER THROUGH THE
WEEKEND. MAX TEMPERATURES AWAY FROM THE BEACHES WILL BE IN THE MID
TO UPPER 70S SATURDAY AND LOW TO MID 80S SUNDAY. MINS SATURDAY
NIGHT WILL BE IN THE LOW TO MID 50S WITH UPPER 50S TO AROUND 60
EXPECTED SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...OVERALL THE LONG TERM LOOKS PRETTY QUIET. THERE
IS SOME UNCERTAINTY AS TO HOW FAR SOUTH A BACKDOOR COLD FRONT
PROGRESSES EARLY IN THE PERIOD. MODEL GUIDANCE HAS SHIFTED A BIT TO
THE SOUTH AND THE BOUNDARY MAY ENTER NORTHERN ZONES. SOME VERY LOW
POPS HAVE BEEN ADDED AS A RESULT. AS THE PARENT HIGH SHIFTS EASTWARD
OFF THE MID ATLANTIC COAST THIS BOUNDARY WILL MOVE BACK TO THE NORTH
IN A WEAKENING STATE AROUND WEDNESDAY. THE LATTER PART OF THE WEEK
WILL BRING RISING HEIGHTS AS UPPER RIDGE BUILDS AND HIGHEST SFC
PRESSURES OFF THE COAST.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...PRECIP HAS MOVED EAST OF ALL AREA TERMINALS. CEILINGS
ALREADY WELL ABOVE VFR AND WILL CONTINUE TO TREND UPWARD THROUGH THE
EVENING. A WEAK SURFACE PRESSURE FIELD OVER THE AREA WILL KEEP WINDS
ON THE LIGHT AND VARIABLE SIDE OVERNIGHT...BECOMING ESTABLISHED FROM
THE WEST-SOUTHWEST DURING SATURDAY AS HIGH PRESSURE BEGINS TO BUILD
IN FROM THE GULF COAST.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS LATE MONDAY INTO EARLY
TUESDAY ASSOCIATED WITH A STALLED FRONT TO OUR NORTH. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM FRIDAY...NO ADVISORIES OR EXERCISE CAUTION HEADLINES
WILL BE NEEDED OVERNIGHT. WINDS WILL BE CHANGEABLE BUT NOT STRONG
AS A SECONDARY BUT WEAK COLD FRONT PASSES ACROSS THE COAST INTO
EARLY SATURDAY JUST PRIOR TO OR AROUND DAYBREAK. SEAS MAINLY 2-3
FEET IN A MIX OF 2-3 FT SSE WAVES EVERY 6-8 SECONDS AND A LIGHT
CHOP. LIGHT S-SW WINDS TONIGHT WILL PREVAIL...FOLLOWED BY A WIND-
SHIFT TO THE NW INTO FIRST LIGHT OF SATURDAY AS THE FRONT MOVES
THROUGH. NO TSTMS EXPECTED OVER THE INSHORE WATERS...BUT A FEW
STORMS MAY LIGHT UP THE GULF STREAM INTO EARLY SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...LIGHT WEST TO SOUTHWEST FLOW AROUND 10 KT IS
EXPECTED SATURDAY AND SATURDAY NIGHT BEFORE BECOMING SOLIDLY SW
SUNDAY AND INCREASING TO 15 KT BY AFTERNOON AND CONTINUING INTO
SUNDAY NIGHT. WINDS WILL BECOME MORE WESTERLY NORTHERN WATERS LATE
AS A FRONT APPROACHES FROM THE NORTH. SEAS OF 2 TO 3 FT EARLY
SATURDAY WILL SUBSIDE TO 2 FT OR LESS BY SATURDAY EVENING AND
CONTINUE INTO SUNDAY BEFORE BUILDING TO 2 TO 3 FT BY SUNDAY NIGHT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...WITH A BACKDOOR COLD FRONT STALLED CLOSE TO IF
NOT ACROSS THE REGION FOR MOST OF THE PERIOD WINDS AND SEAS WILL
BOTH BE RATHER MINIMAL. THERE IS SOME UNCERTAINTY REGARDING HOW FAR
SOUTH THE BOUNDARY WILL SAG HOWEVER AND THIS TRANSLATES TO SOME
POSSIBLE ERROR IN WIND FCST OVER MAINLY NRN ZONES. SRN ZONES SHOULD
REMAIN ON THE SOUTH SIDE OF THE BOUNDARY AND THUS KEEP A
PREDOMINANTLY SOUTHWESTERN FLOW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...MJC
SHORT TERM...31
LONG TERM...MBB
AVIATION...CRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
230 PM EDT THU MAY 1 2014
.SYNOPSIS... A COLD FRONT WILL MOVE SLOWLY EASTWARD ACROSS THE
REGION THROUGH TONIGHT. WEAK HIGH PRESSURE WILL EXTEND ACROSS THE
REGION FRIDAY... THEN A WEAK SURFACE TROUGH WILL CROSS THE AREA
EARLY SATURDAY. HIGH PRESSURE RETURNS LATE SATURDAY THROUGH SUNDAY
WITH A WARMING TREND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...
DRIER AIR...BOTH AT THE SURFACE AND IN THE MID-LEVELS...IS BEGINNING
TO FILTER ACROSS THE STATE AS THE UPPER LOW OVER THE MIDWEST BEGINS
TO LIFT NORTHEAST AND THE DEEP LAYER FLOW OVER OUR REGION SLOWLY
VEERS TO MORE SOUTHWESTERLY. DEWPOINTS HAVE DROPPED INTO THE LOWER
60S IN THE WESTERN PIEDMONT...BUT THE MAIN COLD FRONT IS STILL WEST
OF THE AREA. THE COASTAL PAIN WILL BE THE PRIMARY AREA FOR
CONVECTIVE DEVELOPMENT THIS AFTERNOON...WHERE DEWPOINTS IN THE UPPER
60S WILL STILL SUPPORT SOME WEAK MLCAPE OF UP TO 500 J/KG. DESPITE
STRONG DEEP LAYER SHEAR...THE THREAT OF SEVERE WEATHER WILL BE
STRONGLY INHIBITED BY THE LACK OF BETTER INSTABILITY. THE MOST
RECENT HRRR RUN SHOWS SHOWERS AND POSSIBLY ISOLATED STORMS AS JUST
EAST OF SCOTLAND/HOKE/HARNETT COUNTIES BY 18Z...BUT THAT MAY EVEN BE
TOO FAR WEST BASED ON UPSTREAM RADAR TRENDS. WILL MAKE SOME
ADJUSTMENTS TO POPS AND SKY COVER THIS MORNING...LOWERING BOTH OVER
THE CENTRAL PIEDMONT...KEEP A CHANCE OF SHOWERS AND ISOLATED STORMS
ALL EAST OF I-95. OTHERWISE...THE CURRENT FORECAST FOR MID 70S TO
LOWER 80S AND SOUTHWESTERLY WINDS GUSTING TO 24-28KT OVER THE
PIEDMONT LOOKS GOOD.
TONIGHT...SFC FRONT EXITS THE COASTAL PLAIN EARLY. WLY FLOW WILL
ADVECT A DRIER MORE STABLE AIR MASS INTO THE REGION. SUBSIDENCE
BEHIND THE DEPARTING MID LEVEL TROUGH WEAK SO MAY SEE CLOUDS LINGER
A BIT LONGER THAN NORMAL. MIN TEMPS AROUND 50 NW TO THE MID-UPPER
50S EAST.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 AM THURSDAY...
FRIDAY...WEAK SFC HIGH WILL EXTEND ACROSS THE REGION IN THE
MORNING...GIVING WAY TO A LEE SIDE TROUGH IN THE AFTERNOON. A WEAK
S/W IN THE MID LEVELS WILL APPROACH FROM TEH WEST AND CROSS THE
REGION LATE IN THE DAY. THIS FEATURE WILL ENHANCE CLOUD
COVERAGE...PARTICULARLY OVER THE SE HALF FRIDAY AFTERNOON. BASED ON
FAVORABLE TIMING...COULD SEE A FEW SHOWERS OCCUR DURING THE
AFTERNOON HOURS OVER THE SE COUNTIES. DETERRENT TO SHOWER
DEVELOPMENT WILL BE LACK OF ADEQUATE MOISTURE.
NOTICEABLY COOLER FRIDAY AS LOW LEVEL THICKNESSES AVERAGE 30M BELOW
NORMAL. MAX TEMPS NEAR 70-LOWER 50S.
FRIDAY NIGHT...SUBSIDENCE BEHIND EXITING MID LEVEL S/W AND LOW-MID
FLOW VEERING TO A MORE NW DIRECTION WILL AID TO DIMINISH CLOUD
COVERAGE. WITH CLEARING SKIES AND LIGHT WINDS IN A DRY AIR
MASS...TEMPS SHOULD LOWER INTO THE 40S ACROSS THE PIEDMONT...AND
AROUND 50 IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 230 PM THURSDAY...
FOR SAT/SAT NIGHT: THE MID LEVEL TROUGH AXIS AND ASSOCIATED
VORTICITY LOBE WILL CROSS THE CAROLINAS AND SOUTHEAST STATES SAT...
YIELDING LITTLE MORE THAN CLOUDS FOR CENTRAL NC... PARTICULARLY
EARLY IN THE DAY... GIVEN THE DRY AIR IN PLACE BELOW 5 000 FT. THE
LATTER HALF OF THE DAY SHOULD SEE STABILIZING AND DRYING MID LEVELS
WITH RISING HEIGHTS AND A SURFACE RIDGE IN PLACE (EXTENDING IN FROM
THE SOUTHWEST) WITH DIFFLUENT DOWNSLOPE FLOW WITHIN THE WELL-MIXED
BOUNDARY LAYER... LEADING TO JUST A FEW FLAT DIURNAL CLOUDS. A
BACKDOOR COLD FRONT INITIALLY ORIENTED W-E IS STILL EXPECTED TO PUSH
SOUTHWARD (PROPELLED BY STRONG SHORTWAVE ENERGY DIVING THROUGH THE
BASE OF A DEEPENING VORTEX OVER THE NRN GREAT LAKES) TOWARD NC SAT
NIGHT BUT STILL HOLDING TO OUR NORTH DURING THIS TIME. THICKNESSES
START SAT ABOUT 15 M BELOW NORMAL BUT RECOVER NICELY THROUGH THE
DAY... AND SHOULD DROP LESS THAN USUAL SAT NIGHT... ALTHOUGH
GENERALLY CLEAR SKIES WITH LIGHT WINDS AND DECOUPLING SHOULD ALLOW
FOR GOOD RADIATIONAL COOLING. THIS ALL SUPPORTS HIGHS OF 71-75 AND
LOWS 48-54.
FOR SUN/SUN NIGHT: A WARM AND DEEPLY MIXED BOUNDARY LAYER WILL
EVOLVE SUNDAY SOUTH OF THE SHARPENING W-E FRONTAL ZONE STRETCHING
ACROSS VA... AS THE MID LEVEL VORTEX CROSSES NEW ENGLAND WHILE
DEEPENING IN BOTH PRESSURE AND VERTICAL EXTENT. STRENGTHENING LOW
LEVEL WINDS FROM THE WSW (SURFACE) AND WEST (925-850 MB) WILL RESULT
IN WARM/DRY AND BLUSTERY CONDITIONS... WITH GUSTS POTENTIALLY
APPROACHING 25 MPH. WILL NEED TO MONITOR CONDITIONS FOR POSSIBLE
ADVERSE EFFECTS ON FIRE BEHAVIOR. OTHERWISE... EXPECT JUST SCATTERED
HIGH-BASED FLAT DIURNAL CLOUDS. THE NAM DEPICTS WEAK PERTURBATIONS
IN THE NORTHWEST FLOW TRACKING SOUTHEAST ACROSS NC... PRODUCING
LIGHT AND PATCHY SHOWERS. AT THIS TIME IT APPEARS THAT THE BOUNDARY
LAYER WILL BE TOO DRY AND THE 800-700 MB MOISTURE TOO SHALLOW TO
SUPPORT ANY MEASURABLE PRECIP... SO WILL LEAVE THE SUNDAY FORECAST
DRY. WARM HIGHS OF 79-83. FORECAST CONFIDENCE DECREASES SUN NIGHT AS
THE SURFACE FRONTAL ZONE BECOMES MORE NW-SE ORIENTED WHILE THE MID
LEVEL LOW DIGS JUST OFF NEW ENGLAND. MODEL SOLUTIONS DIVERGE WITH
THE GFS PUSHING THE BACKDOOR FRONT WELL TO THE SSW THROUGH MUCH OF
THE CWA WITH INCREASING CLOUDS... A DEPARTURE FROM THE 00Z ECMWF
WHICH KEPT THE FRONT JUST TO OUR NE SUN NIGHT. SUCH DETAILS CANNOT
BE DEFINITIVELY RESOLVED AT THIS RANGE... SO WILL OPT FOR A MIDDLE-
OF-THE-ROAD SOLUTION AND BRING THE FRONT INTO THE NE CWA BUT NOT ALL
THE WAY THROUGH... A REASONABLE COMPROMISE IN THIS SORT OF PATTERN.
EXPECT A TREND PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE NRN/ERN CWA
SUN NIGHT. LOWS FROM AROUND 50 FAR NE TO 57 SW.
FOR MON THROUGH THU: NORTHWEST FLOW PERSISTS OVER THE REGION MON
INTO WED AS BROAD RIDGING HOLDS OVER THE CENTRAL CONUS... WITH THE
WELL-DEFINED FRONTAL ZONE HOLDING ACROSS FAR NRN AND NE NC. THE
ECMWF/GFS AGREE ON WAVES OF LOW PRESSURE TRACKING ALONG THE FRONT
OVER NC WITH ROUNDS OF SCATTERED STORMS LATE MON INTO MON NIGHT AND
AGAIN LATE TUE INTO TUE NIGHT... MAINLY ACROSS THE NE PORTION OF THE
CWA... AND WITH INCREASING CONFIDENCE IN THIS SCENARIO WILL BUMP UP
POPS MAINLY FROM THE TRIANGLE NORTH AND EAST DURING THESE PERIODS.
MID LEVEL TROUGHING WILL DIG OVER THE ROCKIES AND SHIFT EASTWARD MID-
LATE WEEK... SHIFTING THE MEAN MID LEVEL RIDGE EASTWARD INTO THE MID-
SOUTH/SOUTHEAST STATES... AND GRADUALLY KICKING THE FRONTAL ZONE
BACK TO OUR NE BY THU. WILL EXTEND SMALL POPS INTO WED... THEN TREND
DOWN TO DRY WEATHER THU WITH WARMING TEMPS AS WELL GET FULLY BACK
INTO THE WARM SECTOR WITH STABILIZING MID LEVELS. -GIH
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM THURSDAY...
CONDITIONS ARE VFR ACROSS CENTRAL NC THIS AFTERNOON WITH A DECK OF
MIC AND HIGH CLOUDS ACROSS PORTIONS OF SOUTHEASTERN NC. AN AREA OF
SHOWERS OVER EASTERN SC WILL MAKES ITS WAY NORTHEAST INTO THE
COASTAL PLAIN OF NC...AND MAY BRING A PERIOD OF MVFR AND SHOWERS TO
KFAY AND KRWI BETWEEN 19Z AND 23Z. AN ISOLATED THUNDERSTORM IS
POSSIBLE AS WELL...THOUGH CONDITIONS ARE NOT LOOKING AS FAVORABLE AT
THIS TIME. MEANWHILE...A COLD FRONT WILL PUSH EAST ACROSS THE AREA
LATE THIS AFTERNOON AND EVENING...CAUSING THE GUSTY SOUTHWESTERLY
WINDS AHEAD OF THE FRONT TO SHIFT TO WEST-NORTHWESTERN BETWEEN 00Z
AND 06Z. LIGHTER WINDS ARE EXPECTED OVERNIGHT...BECOMING MORE
SOUTHERLY AGAIN BY FRIDAY AFTERNOON. ANOTHER DISTURBANCE WILL MOVE
ALONG THE COAST ON FRIDAY..POTENTIALLY BRING A FEW ISOLATED SHOWERS
TO AREAS JUST EAST OF KFAY AND KRWI.
OUTLOOK...
VFR CONDITIONS RETURN FOR SATURDAY THROUGH MONDAY....WITH
SOME UNSETTLED WEATHER POSSIBLE EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
140 PM EDT THU MAY 1 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY EASTWARD ACROSS CENTRAL
NORTH CAROLINA TODAY AND TONIGHT. WEAK HIGH PRESSURE WILL EXTEND
ACROSS THE REGION FRIDAY FOLLOWED BY A WEAK SURFACE TROUGH THAT WILL
CROSS CENTRAL NORTH CAROLINA FRIDAY NIGHT THROUGH EARLY SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...
DRIER AIR...BOTH AT THE SURFACE AND IN THE MID-LEVELS...IS BEGINNING
TO FILTER ACROSS THE STATE AS THE UPPER LOW OVER THE MIDWEST BEGINS
TO LIFT NORTHEAST AND THE DEEP LAYER FLOW OVER OUR REGION SLOWLY
VEERS TO MORE SOUTHWESTERLY. DEWPOINTS HAVE DROPPED INTO THE LOWER
60S IN THE WESTERN PIEDMONT...BUT THE MAIN COLD FRONT IS STILL WEST
OF THE AREA. THE COASTAL PAIN WILL BE THE PRIMARY AREA FOR
CONVECTIVE DEVELOPMENT THIS AFTERNOON...WHERE DEWPOINTS IN THE UPPER
60S WILL STILL SUPPORT SOME WEAK MLCAPE OF UP TO 500 J/KG. DESPITE
STRONG DEEP LAYER SHEAR...THE THREAT OF SEVERE WEATHER WILL BE
STRONGLY INHIBITED BY THE LACK OF BETTER INSTABILITY. THE MOST
RECENT HRRR RUN SHOWS SHOWERS AND POSSIBLY ISOLATED STORMS AS JUST
EAST OF SCOTLAND/HOKE/HARNETT COUNTIES BY 18Z...BUT THAT MAY EVEN BE
TOO FAR WEST BASED ON UPSTREAM RADAR TRENDS. WILL MAKE SOME
ADJUSTMENTS TO POPS AND SKY COVER THIS MORNING...LOWERING BOTH OVER
THE CENTRAL PIEDMONT...KEEP A CHANCE OF SHOWERS AND ISOLATED STORMS
ALL EAST OF I-95. OTHERWISE...THE CURRENT FORECAST FOR MID 70S TO
LOWER 80S AND SOUTHWESTERLY WINDS GUSTING TO 24-28KT OVER THE
PIEDMONT LOOKS GOOD.
TONIGHT...SFC FRONT EXITS THE COASTAL PLAIN EARLY. WLY FLOW WILL
ADVECT A DRIER MORE STABLE AIR MASS INTO THE REGION. SUBSIDENCE
BEHIND THE DEPARTING MID LEVEL TROUGH WEAK SO MAY SEE CLOUDS LINGER
A BIT LONGER THAN NORMAL. MIN TEMPS AROUND 50 NW TO THE MID-UPPER
50S EAST.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 AM THURSDAY...
FRIDAY...WEAK SFC HIGH WILL EXTEND ACROSS THE REGION IN THE
MORNING...GIVING WAY TO A LEE SIDE TROUGH IN THE AFTERNOON. A WEAK
S/W IN THE MID LEVELS WILL APPROACH FROM TEH WEST AND CROSS THE
REGION LATE IN THE DAY. THIS FEATURE WILL ENHANCE CLOUD
COVERAGE...PARTICULARLY OVER THE SE HALF FRIDAY AFTERNOON. BASED ON
FAVORABLE TIMING...COULD SEE A FEW SHOWERS OCCUR DURING THE
AFTERNOON HOURS OVER THE SE COUNTIES. DETERRENT TO SHOWER
DEVELOPMENT WILL BE LACK OF ADEQUATE MOISTURE.
NOTICEABLY COOLER FRIDAY AS LOW LEVEL THICKNESSES AVERAGE 30M BELOW
NORMAL. MAX TEMPS NEAR 70-LOWER 50S.
FRIDAY NIGHT...SUBSIDENCE BEHIND EXITING MID LEVEL S/W AND LOW-MID
FLOW VEERING TO A MORE NW DIRECTION WILL AID TO DIMINISH CLOUD
COVERAGE. WITH CLEARING SKIES AND LIGHT WINDS IN A DRY AIR
MASS...TEMPS SHOULD LOWER INTO THE 40S ACROSS THE PIEDMONT...AND
AROUND 50 IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
SATURDAY AND SATURDAY NIGHT: A SOUTHERN STREAM S/W IS EXPECTED TO
SHIFT EASTWARD ACROSS THE DEEP SOUTH/GULF COAST SATURDAY... THEN
OFFSHORE ON SATURDAY NIGHT. THE S/W IS EXPECTED TO HAVE LITTLE
AFFECT ON OUR WEATHER ACROSS CENTRAL NC... OTHER THAN POSSIBLY
SPREADING/HOLDING SOME MID/HIGH LEVEL CLOUD COVER ACROSS SOUTHERN
AND EASTERN PORTIONS OF THE AREA. THE LOW LEVELS SHOULD REMAIN
STABLE WITH A NICE CAPPING INVERSION... WITH MAYBE SOME FLAT CUMULUS
DEVELOPING SATURDAY AFTERNOON. EXPECT HIGH TEMPS ON SATURDAY WILL BE
GENERALLY IN THE 72-76 DEGREE RANGE ACROSS THE AREA IN A NW TO SE/E
FASHION (WARMEST SE/E). LOWS SUNDAY MORNING ARE EXPECTED TO BE IN
THE 50S... WITH CLEAR/MOSTLY CLEAR SKIES WITH A LIGHT WESTERLY TO
NORTHWESTERLY BREEZE.
SUNDAY THROUGH WEDNESDAY: A NORTHERN STREAM S/W IS EXPECTED TO MOVE
ACROSS THE NORTHEASTERN U.S. ON SUNDAY INTO SUNDAY NIGHT. THIS WILL
SEND A GENERALLY DRY COLD FRONT SOUTHWARD AND INTO OUR AREA LATE
SUNDAY INTO SUNDAY NIGHT/MONDAY MORNING. THE FRONT IS EXPECTED TO
SHIFT SOUTH/SOUTHWESTWARD INTO THE AREA WHILE WEAKENING... ALMOST IN
A BACKDOOR FASHION... WITH WESTERLY LOW LEVEL FLOW IN ADVANCE OF THE
FEATURE. THUS... WILL LEAVE THE FORECAST DRY FOR SUNDAY INTO SUNDAY
NIGH AND SHOW TEMPS WARMING INTO THE UPPER 70S AND LOWER 80S ON
SUNDAY AFTERNOON... WITH SOME MID 80S NOT OUT OF THE QUESTION ACROSS
OUR FAR SOUTH AS AFTERNOON LOW LEVEL THICKNESS VALUES ARE EXPECTED
TO APPROACH 1400 METERS. LOWS MONDAY MORNING ARE EXPECTED TO BE NEAR
NORMAL IN THE 50S.
EARLY TO MID NEXT WEEK WILL FEATURE THE AFOREMENTIONED FRONT STALLING
ACROSS THE AREA... WHILE POSSIBLE DISTURBANCE TRACK ALONG THIS
FEATURE IN THE NORTHWESTERLY MID LEVEL FLOW AS MID LEVEL RIDGING
BUILDS TO THE WEST. SUCH DISTURBANCES IN NW FLOW ARE HARD TO TRACK
THIS FAR OUT IN THE FORECAST. THUS... WILL LIMIT POPS TO SLIGHT
CHANCE FOR NOW DURING THIS TIME FRAME. WRT TEMPS... THE POSITION OF
THE FRONT (WHICH MAY SHIFT BACK AND FORTH WITH PASSING DISTURBANCES)
WILL PLAY A MAJOR ROLE IN TEMPS. FOR NOW WILL TREND THE WARMEST
TEMPS SW AND COOLEST NE. THIS YIELD HIGH TEMPS GENERALLY IN THE 70S
NE TO 80S SW. LOWS ARE EXPECTED TO GENERALLY BE IN THE 50S TO LOWER
60S DURING THIS TIME.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM THURSDAY...
CONDITIONS ARE VFR ACROSS CENTRAL NC THIS AFTERNOON WITH A DECK OF
MIC AND HIGH CLOUDS ACROSS PORTIONS OF SOUTHEASTERN NC. AN AREA OF
SHOWERS OVER EASTERN SC WILL MAKES ITS WAY NORTHEAST INTO THE
COASTAL PLAIN OF NC...AND MAY BRING A PERIOD OF MVFR AND SHOWERS TO
KFAY AND KRWI BETWEEN 19Z AND 23Z. AN ISOLATED THUNDERSTORM IS
POSSIBLE AS WELL...THOUGH CONDITIONS ARE NOT LOOKING AS FAVORABLE AT
THIS TIME. MEANWHILE...A COLD FRONT WILL PUSH EAST ACROSS THE AREA
LATE THIS AFTERNOON AND EVENING...CAUSING THE GUSTY SOUTHWESTERLY
WINDS AHEAD OF THE FRONT TO SHIFT TO WEST-NORTHWESTERN BETWEEN 00Z
AND 06Z. LIGHTER WINDS ARE EXPECTED OVERNIGHT...BECOMING MORE
SOUTHERLY AGAIN BY FRIDAY AFTERNOON. ANOTHER DISTURBANCE WILL MOVE
ALONG THE COAST ON FRIDAY..POTENTIALLY BRING A FEW ISOLATED SHOWERS
TO AREAS JUST EAST OF KFAY AND KRWI.
OUTLOOK...
VFR CONDITIONS RETURN FOR SATURDAY THROUGH MONDAY....WITH
SOME UNSETTLED WEATHER POSSIBLE EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 AM EDT THU MAY 1 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY EASTWARD ACROSS CENTRAL
NORTH CAROLINA TODAY AND TONIGHT. WEAK HIGH PRESSURE WILL EXTEND
ACROSS THE REGION FRIDAY FOLLOWED BY A WEAK SURFACE TROUGH THAT WILL
CROSS CENTRAL NORTH CAROLINA FRIDAY NIGHT THROUGH EARLY SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...
DRIER AIR...BOTH AT THE SURFACE AND IN THE MID-LEVELS...IS BEGINNING
TO FILTER ACROSS THE STATE AS THE UPPER LOW OVER THE MIDWEST BEGINS
TO LIFT NORTHEAST AND THE DEEP LAYER FLOW OVER OUR REGION SLOWLY
VEERS TO MORE SOUTHWESTERLY. DEWPOINTS HAVE DROPPED INTO THE LOWER
60S IN THE WESTERN PIEDMONT...BUT THE MAIN COLD FRONT IS STILL WEST
OF THE AREA. THE COASTAL PAIN WILL BE THE PRIMARY AREA FOR
CONVECTIVE DEVELOPMENT THIS AFTERNOON...WHERE DEWPOINTS IN THE UPPER
60S WILL STILL SUPPORT SOME WEAK MLCAPE OF UP TO 500 J/KG. DESPITE
STRONG DEEP LAYER SHEAR...THE THREAT OF SEVERE WEATHER WILL BE
STRONGLY INHIBITED BY THE LACK OF BETTER INSTABILITY. THE MOST
RECENT HRRR RUN SHOWS SHOWERS AND POSSIBLY ISOLATED STORMS AS JUST
EAST OF SCOTLAND/HOKE/HARNETT COUNTIES BY 18Z...BUT THAT MAY EVEN BE
TOO FAR WEST BASED ON UPSTREAM RADAR TRENDS. WILL MAKE SOME
ADJUSTMENTS TO POPS AND SKY COVER THIS MORNING...LOWERING BOTH OVER
THE CENTRAL PIEDMONT...KEEP A CHANCE OF SHOWERS AND ISOLATED STORMS
ALL EAST OF I-95. OTHERWISE...THE CURRENT FORECAST FOR MID 70S TO
LOWER 80S AND SOUTHWESTERLY WINDS GUSTING TO 24-28KT OVER THE
PIEDMONT LOOKS GOOD.
TONIGHT...SFC FRONT EXITS THE COASTAL PLAIN EARLY. WLY FLOW WILL
ADVECT A DRIER MORE STABLE AIR MASS INTO THE REGION. SUBSIDENCE
BEHIND THE DEPARTING MID LEVEL TROUGH WEAK SO MAY SEE CLOUDS LINGER
A BIT LONGER THAN NORMAL. MIN TEMPS AROUND 50 NW TO THE MID-UPPER
50S EAST.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 AM THURSDAY...
FRIDAY...WEAK SFC HIGH WILL EXTEND ACROSS THE REGION IN THE
MORNING...GIVING WAY TO A LEE SIDE TROUGH IN THE AFTERNOON. A WEAK
S/W IN THE MID LEVELS WILL APPROACH FROM TEH WEST AND CROSS THE
REGION LATE IN THE DAY. THIS FEATURE WILL ENHANCE CLOUD
COVERAGE...PARTICULARLY OVER THE SE HALF FRIDAY AFTERNOON. BASED ON
FAVORABLE TIMING...COULD SEE A FEW SHOWERS OCCUR DURING THE
AFTERNOON HOURS OVER THE SE COUNTIES. DETERRENT TO SHOWER
DEVELOPMENT WILL BE LACK OF ADEQUATE MOISTURE.
NOTICEABLY COOLER FRIDAY AS LOW LEVEL THICKNESSES AVERAGE 30M BELOW
NORMAL. MAX TEMPS NEAR 70-LOWER 50S.
FRIDAY NIGHT...SUBSIDENCE BEHIND EXITING MID LEVEL S/W AND LOW-MID
FLOW VEERING TO A MORE NW DIRECTION WILL AID TO DIMINISH CLOUD
COVERAGE. WITH CLEARING SKIES AND LIGHT WINDS IN A DRY AIR
MASS...TEMPS SHOULD LOWER INTO THE 40S ACROSS THE PIEDMONT...AND
AROUND 50 IN THE COASTAL PLAIN AND SANDHILLS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
SATURDAY AND SATURDAY NIGHT: A SOUTHERN STREAM S/W IS EXPECTED TO
SHIFT EASTWARD ACROSS THE DEEP SOUTH/GULF COAST SATURDAY... THEN
OFFSHORE ON SATURDAY NIGHT. THE S/W IS EXPECTED TO HAVE LITTLE
AFFECT ON OUR WEATHER ACROSS CENTRAL NC... OTHER THAN POSSIBLY
SPREADING/HOLDING SOME MID/HIGH LEVEL CLOUD COVER ACROSS SOUTHERN
AND EASTERN PORTIONS OF THE AREA. THE LOW LEVELS SHOULD REMAIN
STABLE WITH A NICE CAPPING INVERSION... WITH MAYBE SOME FLAT CUMULUS
DEVELOPING SATURDAY AFTERNOON. EXPECT HIGH TEMPS ON SATURDAY WILL BE
GENERALLY IN THE 72-76 DEGREE RANGE ACROSS THE AREA IN A NW TO SE/E
FASHION (WARMEST SE/E). LOWS SUNDAY MORNING ARE EXPECTED TO BE IN
THE 50S... WITH CLEAR/MOSTLY CLEAR SKIES WITH A LIGHT WESTERLY TO
NORTHWESTERLY BREEZE.
SUNDAY THROUGH WEDNESDAY: A NORTHERN STREAM S/W IS EXPECTED TO MOVE
ACROSS THE NORTHEASTERN U.S. ON SUNDAY INTO SUNDAY NIGHT. THIS WILL
SEND A GENERALLY DRY COLD FRONT SOUTHWARD AND INTO OUR AREA LATE
SUNDAY INTO SUNDAY NIGHT/MONDAY MORNING. THE FRONT IS EXPECTED TO
SHIFT SOUTH/SOUTHWESTWARD INTO THE AREA WHILE WEAKENING... ALMOST IN
A BACKDOOR FASHION... WITH WESTERLY LOW LEVEL FLOW IN ADVANCE OF THE
FEATURE. THUS... WILL LEAVE THE FORECAST DRY FOR SUNDAY INTO SUNDAY
NIGH AND SHOW TEMPS WARMING INTO THE UPPER 70S AND LOWER 80S ON
SUNDAY AFTERNOON... WITH SOME MID 80S NOT OUT OF THE QUESTION ACROSS
OUR FAR SOUTH AS AFTERNOON LOW LEVEL THICKNESS VALUES ARE EXPECTED
TO APPROACH 1400 METERS. LOWS MONDAY MORNING ARE EXPECTED TO BE NEAR
NORMAL IN THE 50S.
EARLY TO MID NEXT WEEK WILL FEATURE THE AFOREMENTIONED FRONT STALLING
ACROSS THE AREA... WHILE POSSIBLE DISTURBANCE TRACK ALONG THIS
FEATURE IN THE NORTHWESTERLY MID LEVEL FLOW AS MID LEVEL RIDGING
BUILDS TO THE WEST. SUCH DISTURBANCES IN NW FLOW ARE HARD TO TRACK
THIS FAR OUT IN THE FORECAST. THUS... WILL LIMIT POPS TO SLIGHT
CHANCE FOR NOW DURING THIS TIME FRAME. WRT TEMPS... THE POSITION OF
THE FRONT (WHICH MAY SHIFT BACK AND FORTH WITH PASSING DISTURBANCES)
WILL PLAY A MAJOR ROLE IN TEMPS. FOR NOW WILL TREND THE WARMEST
TEMPS SW AND COOLEST NE. THIS YIELD HIGH TEMPS GENERALLY IN THE 70S
NE TO 80S SW. LOWS ARE EXPECTED TO GENERALLY BE IN THE 50S TO LOWER
60S DURING THIS TIME.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 740 AM THURSDAY...
SW SFC WINDS WILL BECOME BREEZY THIS MORNING AS A SFC FRONT
APPROACHES FROM THE WEST. WIND GUSTS BETWEEN 23-28KTS WILL OCCUR
FROM LATE MORNING THROUGH THE AFTERNOON. POCKETS OF MVFR CEILING
ACROSS THE NORTHERN PIEDMONT WILL LIFT BY 15Z.OTHERWISE CEILINGS
BETWEEN 3500-7000FT WILL GRADUALLY LIFT WITH PARTIAL CLEARING
PROBABLE IN THE WESTERN PIEDMONT BY EARLY AFTERNOON.
AS THE SFC FRONT CROSSES THE REGION...A FEW SHOWERS AND AN ISOLATED
THUNDERSTORM SHOULD DEVELOP. THE CONVECTIVE COVERAGE ( NO WORSE
THAN SCATTERED) WILL BE GREATEST ALONG AND EAST OF I-95. IN VICINITY
OF THE HEAVIER SHOWERS AND STORMS EXPECT MVFR CONDITIONS DUE TO
CEILING/VISIBILITY.
WEAK HIGH PRESSURE WILL BUILD INTO CENTRAL NC TONIGHT AND FRIDAY.
THIS FEATURE WILL AID TO SUBSIDE THE WINDS AND BRING VFR CONDITIONS
TO THE REGION. THERE WILL BE A SCATTERING OF CLOUDS BETWEEN 3500-
5000FT TONIGHT INTO FRIDAY.
VFR CONDITIONS ANTICIPATED FOR SATURDAY THROUGH MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
941 AM CDT THU MAY 1 2014
.UPDATE...
ISSUED AT 941 AM CDT THU MAY 1 2014
CURRENT RADAR SHOWING VERY WEAK ECHOES OVER PORTIONS OF WEST
CENTRAL MINNESOTA WITH SOME WEAK ECHOES MOVING INTO THE NORTHERN
VALLEY AS WELL. THE ONLY GROUND TRUTH WITH THIS ROUND OF OBS HAS
BEEN AT BEMIDJI. HOWEVER A LOT OF THESE RETURNS ARE SO WEAK IT IS
DOUBTFUL THEY ARE REACHING THE GROUND...ESPECIALLY IN TERMS OF
MEASURABLE PRECIP. THEREFORE I HAVE CUT 40 POPS DOWN TO 30S BUT
DID ADD SOME ISOLATED SHRA OVER NORTHERN VALLEY. ALSO UPDATED
WINDS WITH 12Z RAP DATA AND BUMPED UP SUSTAINED WINDS A COUPLE OF
KNOTS AS WELL AS WIND GUSTS. GRADIENT WILL WEAKEN THROUGHOUT DAY
BUT ENOUGH MIXING OCCURRING TO GIVE US HIGHER WINDS THAN PREV FCST
INDICATED.
UPDATE ISSUED AT 701 AM CDT THU MAY 1 2014
NO CHANGES AT THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 405 AM CDT THU MAY 1 2014
WATER VAPOR LOOP INDICATED UPPER LEVEL LOW PRESSURE SYSTEM WAS
LOCATED OVER THE WI/IL BORDER WITH SHORT WAVES ROTATING AROUND THE
SYSTEM. UPPER LEVEL RIDGE WAS LOCATED OVER SASK/MAN WITH NEXT SHORT
WAVE TROUGH OVER NORTHERN ALTA. UPPER LEVEL RIDGE AND UPSTREAM SHORT
WAVE WILL FINALLY KICK WI LOW EAST TODAY AND TONIGHT. HOWEVER THIS
JUST CHANGES REGIME WITH SHORT WAVE MOVING IN FROM THE NORTHWEST
LATER TONIGHT AND FRI. UPPER LEVEL LOW OVER THE NORTHWEST
TERRITORIES WILL MOVE ACROSS SOUTHERN CANADA SAT BUT AT LEAST THE
PATTERN IS PROGRESSIVE.
CLOUDS AND PERIODS OF RAIN OVER THE AREA WILL SLOWLY SHIFT SOUTH AND
EAST TODAY AND DISSIPATE. WENT A LITTLE COOLER IN THE EAST TODAY WITH
MORE CLOUDS. GENERALLY WENT A LITTLE WARMER FOR FRI AND SAT.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 405 AM CDT THU MAY 1 2014
FOR SUNDAY THROUGH WEDNESDAY...IT WILL BE DRY AND PLEASANT ON
SUNDAY...AND TEMPS COULD APPROACH 60 AND HAVE TRENDED TEMPS A BIT
WARMER WITH AT LEAST SOME SUNSHINE EXPECTED. IT WILL BECOME VERY
UNSETTLED NEXT WEEK...WITH SEVERAL CHANCES FOR MEASURABLE RAINFALL.
IT APPEARS THAT A POTENTIALLY LARGER QPF EVENT COULD OCCUR TOWARDS
THE MIDDLE OF NEXT WEEK...AS MOIST SW FLOW ALOFT DEVELOPS. TEMPS
SHOULD MODERATE FROM WHAT WE HAVE SEEN...ALTHOUGH STILL REMAIN A BIT
BELOW NORMAL WITH LACK OF TOO MUCH SUNSHINE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 701 AM CDT THU MAY 1 2014
MVFR TO IFR CIGS WERE OVER THE SOUTHEAST HALF OF THE THE AREA OR
SOUTH AND EAST OF A LINE ROUGHLY FROM BDE TO OAKES ND. FOG
LOOP/SURFACE OBS INDICATED SOME BREAKS IN THE CLOUDS OVER EASTERN ND
AND FAR NORTHWEST MN. CLEARING LINE EXTENDED FROM NEAR GEORGE ISLAND
(LAKE WINNIPEG) TO BRANDON MAN TO MOT. TRAILING EDGE OF LINE WAS
SHIFTING SOUTHEAST AROUND 10 KNOTS. CLEARING LINE WILL FORECAST TO
CONTINUE MOVING SOUTHEAST AT 10 KNOTS THROUGH THE DAY. MVFR/IFR CIGS
OVER THE SOUTHEAST HALF OF THE AREA ARE EXPECTED TO SLOWLY LIFT
THROUGH THE MORNING. NEXT SYSTEM TO MOVE INTO THE NORTHWEST PART OF
THE AREA THIS EVENING.
&&
.HYDROLOGY...
ISSUED AT 1242 PM CDT WED APR 30 2014
THE WARNINGS AT HALLOCK AND HARWOOD HAVE BEEN CANCELLED.
MODERATE FLOODING CONTINUES AT ABERCROMBIE AND LOOKS TO BE CRESTING
JUST ABOVE 17 FEET. THE CREST ON THE RED RIVER IS THROUGH WAHPETON
AND HEADING NORTH TO FARGO WITH 6K CFS. THE ABERCROMBIE WATER WILL
MERGE INTO THE RED SOUTH OF FARGO IN THE NEXT 36 HRS WITH THE RED
WATER SHORTLY THEREAFTER...CAUSING 27 TO 28 FT TO BE REALIZED AT
FARGO.
THIS FARGO CREST WILL MOVE ITS WAY NORTHWARD AS WARNINGS HAVE BEEN
ISSUED DOWNSTREAM THROUGH OSLO...WITH A FLOOD WATCH AT DRAYTON. NO
SIGNIFICANT RAIN IS EXPECTED THROUGH THIS WEEKEND...ALTHOUGH THERE
WILL BE SEVERAL CHANCES FOR SOME RAIN...THAT SHOULDN/T AMOUNT TO
MUCH MORE THAN A FEW TENTHS OF AN INCH AT MOST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...HOPPES
LONG TERM...DK
AVIATION...HOPPES
HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
137 PM EDT THU MAY 1 2014
.SYNOPSIS...
COOLER AND DRY HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER INTO
THIS WEEKEND AS A STALLED OUT FRONT PERSISTS FROM FLORIDA TO OFF THE
CAROLINA COAST. THE UPPER TROUGH WILL SLOWLY MOVE OVER THE ATLANTIC
AS AN UPPER RIDGE BUILDS IN FROM THE WEST. THIS WILL RESULT IN
WARMER TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM...SHRA AND TSRA DEVELOPING SOUTH OF THE CWFA AS
EXPECTED. LATEST MESOSCALE GUIDANCE CONTINUES TO KEEP THIS ACTIVITY
SOUTH OF THE CWFA...SO HAVE FOLLOWED THAT LEAD. ALTHOUGH SKIES HAVE
MOSTLY CLEARED...CIRRUS IS RETURNING FROM THE SW. EXPECT THIS CIRRUS
AND SOME LOWER CLOUDS TO CONTINUE THRU THE DAY. HAVE ADJUSTED HIGHS A
LITTLE HIGHER IS SOME LOCATIONS...IN LINE WITH CURRENT CONDITIONS
AND LATEST GUIDANCE.
AS OF 1030 AM...SKIES HAVE CLEARED ACROSS MUCH OF THE CWFA WITH
CLOUDS LINGERING ACROSS THE TN BORDER AND SRN AND ERN CWFA. EXPECT
THE CLOUDS TO LINGER IN THESE AREAS THRU THE EARLY AFTERNOON THEN
CLEAR BY EVENING. LATEST MESOSCALE GUIDANCE SHOWS SH/TSRA ASSOCIATED
WITH A WAVE AND UPPER JET REMAINING SOUTH OF THE CWFA THIS
AFTERNOON. USED A BLEND WHICH KEEPS ONLY A BRIEF ISOLATED SHRA FOR
THE EXTREME SRN CWFA BORDER EARLY THIS AFTERNOON. STILL EXPECT GUSTY
SW WINDS OUTSIDE OF THE MTNS AND GUSTY NW WINDS ACROSS THE MTNS THIS
AFTERNOON. HIGH TEMPS LOOK ON TRACK WITH ONLY MINOR ADJUSTMENTS BY
BLENDING IN LATEST GUIDANCE.
AS OF 630 AM EDT...NO NEED TO MAKE ANY MAJOR CHANGES TO THE FCST.
UPPER CI CONTINUES TO OVERSPREAD LLVL STCU AT MOST LOCALES. SLOW
MOVING COLD FRONT HAS REACHED THE ERN HALF OF THE CWFA WITH NO UPPER
SUPPORT...THUS LITTLE PRECIP EXCEPT FOR A COUPLE WEAK LINES OF -SHRA
OVER THE ERN ZONES. CURRENT SLIGHT POPS HAVE THIS IN CHECK. TEMPS
HAVE BEEN HELD UP WITH CLOUD COVER / MIXING...WITH LOW END GUSTS
SHOWING UP AT KCLT. TDDS ARE REMAINING LARGE ENUF TO PRECLUDE A FG
THREAT WITH SOME LOW LYING AREAS IN THE NRN FTHILLS BEING THE
EXCEPTION. WILL ADJ HR/LY TEMPS AND TDS A BIT.
A WEAK COLD FRONT IS MAKING ITS WAY EAST ACROSS THE CWFA ATTM WITH
LITTLE FANFARE. THERE IS A WEAK LINE OF -SHRA MOVING EAST ACROSS THE
NRN FOOTHILLS AND WILL EXPECT THIS TO CONTINUE EAST THROUGH THE
MORNING REMAINING IN THE NW PIEDMONT. THE HRRR IS HANDLING THIS
SITUATION MUCH BETTER THAN THE OTHER HIRES MODELS AND THERE IS NO
NEED TO JUMP OUTSIDE OF ITS GENERAL GUIDANCE. POPS HAVE BEEN ADJ
DOWN INTO THE ISOL RANGE WHICH SHOULD WORK OUT PRETTY GOOD.
THE ATMOS WILL REMAIN WEAKLY FORCED THROUGH THE AFTERNOON AS THE
MASSIVE CLOSED LOW SLOWLY BEGINS TO BREAK DOWN AND PULL NE. THIS
WILL GENERALLY LEAVE THE FCST AREA IN A MODEST SUBSIDENCE REGIME
SLOWING THE SFC FRONT AND WASHING IT OUT. THUS...THERE WONT BE MUCH
OF A WIND SHIFT WITH THE TROF AXIS. THERE WILL BE A GOOD GUST
POTENTIAL AS MIXING ALLOWS 20-25 KT MOMENTUM TRANSFERS. MAX TEMPS
WILL BE TRICKY AS A TIGHT LLVL THICKNESS GRADIENT MOVES IN...BUT
BECOMES MODIFIED WARMER WITH THE CONTINUED S/LY FLOW...ESP OUTSIDE
THE MTNS. THE GFS IS MORE AGGRESSIVE THAN THE NAM WITH THIS WARMING
MODIFICATION...SO A BLEND WAS TAKEN ALONG WITH A BLEND OF BIAS
CORRECTION...WHICH GIVES MAX TEMPS A DEGREE OR TWO ABOVE NORMAL MOST
LOCALS. THIS COULD BE A TAD LOW THO IN GOOD INSOLATION.
OVERNIGHT...THE PRESSURE GRADIENT BEGINS TO RELAX AS HIGH PRESSURE
MOVES IN FROM THE SW AND THE AREA BECOMES LESS INFLUENCED BY THE
WEAKENING ULVL LOW. SKY COVER IS NOT WHOLLY CERTAIN ATTM...BUT MOST
INDICATIONS ARE A CI DECK WILL MOVE IN AND OFFSET MAX COOLING BY A
FEW DEGREES. EVEN WITH THE LOWER MTN THICKNESSES...CLOUD COVER WILL
MOSTLY ELIMINATE A FROST CONCERN EVEN ACROSS THE MTN TOPS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 130 AM THURSDAY...THE SHORT TERM PERIOD INITIALIZES FRIDAY
MORNING WITH A RATHER PROGRESSIVE UPPER TROF SLIDING EAST ACROSS
THE MID MISSISSIPPI RIVER VALLEY AND WEAK SURFACE HIGH PRESSURE
BUILDING INTO THE MIDSOUTH. GUIDANCE CONTINUES TO AGREE ON A QUASI
STATIONARY FRONTAL BOUNDARY LYING ACROSS THE SOUTHEASTERN ATLANTIC
COASTLINE WITH A SURFACE WAVE DEVELOPING OVER THE NORTHERN GULF.
THE GFS SEEMS TO BE THE OUTLIER WITH ITS SOLUTION INDICATING THE
SURFACE WAVE SLIDING NORTHEAST SPREADING SHOWERS ACROSS THE SOUTHERN
TWO THIRDS OF THE FORECAST AREA. THE ECMWF/NAM/CMC KEEP THE WAVE
TIED CLOSER TO THE COASTLINE RESULTING IN A DRY FORECAST FOR
NORTHEAST GA AND THE WESTERN CAROLINAS. THAT SAID...ALL SOLUTIONS
CONVERGE ON SUFFICIENT UPPER DIVERGENCE TO SUPPORT MOSTLY CLOUDY
SKIES THANKS TO PROXIMITY OF THE RIGHT REAR ENTRANCE REGION OF AN
EJECTING UPPER JET MAX. BEYOND THAT...THE PATTERN TRANSITIONS
SIGNIFICANTLY WITH A BROAD UPPER TROF SLIDING EAST TAKING ROOT OVER
THE EAST/CENTRAL CONUS THROUGH THE REMAINDER OF THE SHORT TERM
PERIOD. THIS WILL LEAD TO DECREASING CLOUDINESS AND THE START OF A
GRADUAL WARMING TREND. THUS THE SHORT TERM FORECAST WILL FEATURE NO
MENTIONABLE POPS WITH TEMPERATURES ON FRIDAY REMAINING 3-5 DEGREES
BELOW NORMAL BEFORE WARMING TO AROUND NORMAL FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
SUNDAY MORNING WITH DEEP LAYER RIDGING PREVAILING ACROSS THE
SOUTHEAST. A BROAD UPPER RIDGE WILL CONTINUE SLIDING EAST WHILE
SURFACE HIGH PRESSURE REMAINS CENTERED OVER THE GULF OF MEXICO. A
SURFACE CYCLONE OVER EASTERN QUEBEC WILL SLIDE THROUGH THE NORTHEAST
SPREADING A WEAK COLD FRONTAL BOUNDARY SOUTHWARD INTO THE OHIO
VALLEY ON SUNDAY. MEANWHILE...WEAK WAA ACROSS THE LOWER/MID
MISSISSIPPI RIVER VALLEY WILL PRESENT A ZONE OF CONVERGENCE ALONG
THE DESCENDING BRANCH OF THE UPPER TROF. GUIDANCE HINTS AT
POTENTIAL ACTIVATION ALONG THIS BOUNDARY LEADING SHOWERS/MCS
SPILLING EAST INTO THE CENTRAL APPALACHIANS. HOWEVER...THIS
ACTIVITY LOOKS TO REMAIN JUST NORTH OF THE FORECAST AREA THEREFORE
DECIDED NOT TO INCLUDE ANY MENTIONABLE POPS AT THIS RANGE. BEYOND
THAT...THE UPPER RIDGE ADVECTS FURTHER EAST WITH A SERIES OF
POTENTIAL EVENING/NOCTURNAL MCS EVENTS PASSING NORTH OF THE FORECAST
AREA THROUGH THE REMAINDER OF THE PERIOD. THE ABOVE MENTIONED GULF
SURFACE RIDGE WILL TRANSITION TO A BERMUDA TYPE HIGH BY MIDWEEK
SETTING UP THE RETURN OF LOW LEVEL WARM ADVECTION LEADING TO
TEMPERATURES EACH AFTERNOON BEING AN ORDER OF MAGNITUDE ABOVE
NORMAL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AT KCLT...FEW STRATOCU AND BKN CIRRUS WILL CONTINUE THRU THE
AFTERNOON WITH GUSTY SW WINDS. LOW CLOUDS DISSIPATE THIS EVENING BUT
BKN CIRRUS CONTINUES OVERNIGHT. WINDS DIMINISH THIS EVENING BECOMING
WSW THEN NW OVERNIGHT. LIGHT NLY WIND AFTER DAYBREAK BECOMES WSW
AROUND NOON. BKN CIRRUS CONTINUES FRI MORNING WITH FEW060 DEVELOPING
AROUND NOON.
ELSEWHERE...SIMILAR CONDITIONS AS KCLT. KAVL THE MAIN EXCEPTION WITH
GUSTY NLY WIND THIS AFTERNOON DIMINISHING THIS EVENING...THEN
CONTINUING THRU THE PERIOD.
OUTLOOK...DRYING CONDITIONS WITH NO RESTRICTIONS EXPECTED SAT
THROUGH TUE. CANNOT RULE OUT SOME MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-17Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CDG
NEAR TERM...RWH/SBK
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...RWH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1036 AM EDT THU MAY 1 2014
.SYNOPSIS...
A COLD FRONT WILL EXIT THE REGION TO THE SOUTHEAST ON THURSDAY
MORNING WITH COOLER/DRIER HIGH PRESSURE BUILDING THROUGH THE
REMAINDER OF THE WORK WEEK. TEMPERATURES WILL WARM THROUGH THE
WEEKEND AND INTO NEXT WEEK AS AN UPPER LEVEL RIDGE SLIDES EAST
LEADING TO MORE SEASONABLE WEATHER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM...SKIES HAVE CLEARED ACROSS MUCH OF THE CWFA WITH
CLOUDS LINGERING ACROSS THE TN BORDER AND SRN AND ERN CWFA. EXPECT
THE CLOUDS TO LINGER IN THESE AREAS THRU THE EARLY AFTERNOON THEN
CLEAR BY EVENING. LATEST MESOSCALE GUIDANCE SHOWS SH/TSRA ASSOCIATED
WITH A WAVE AND UPPER JET REMAINING SOUTH OF THE CWFA THIS
AFTERNOON. USED A BLEND WHICH KEEPS ONLY A BRIEF ISOLATED SHRA FOR
THE EXTREME SRN CWFA BORDER EARLY THIS AFTERNOON. STILL EXPECT GUSTY
SW WINDS OUTSIDE OF THE MTNS AND GUSTY NW WINDS ACROSS THE MTNS THIS
AFTERNOON. HIGH TEMPS LOOK ON TRACK WITH ONLY MINOR ADJUSTMENTS BY
BLENDING IN LATEST GUIDANCE.
AS OF 630 AM EDT...NO NEED TO MAKE ANY MAJOR CHANGES TO THE FCST.
UPPER CI CONTINUES TO OVERSPREAD LLVL STCU AT MOST LOCALES. SLOW
MOVING COLD FRONT HAS REACHED THE ERN HALF OF THE CWFA WITH NO UPPER
SUPPORT...THUS LITTLE PRECIP EXCEPT FOR A COUPLE WEAK LINES OF -SHRA
OVER THE ERN ZONES. CURRENT SLIGHT POPS HAVE THIS IN CHECK. TEMPS
HAVE BEEN HELD UP WITH CLOUD COVER / MIXING...WITH LOW END GUSTS
SHOWING UP AT KCLT. TDDS ARE REMAINING LARGE ENUF TO PRECLUDE A FG
THREAT WITH SOME LOW LYING AREAS IN THE NRN FTHILLS BEING THE
EXCEPTION. WILL ADJ HR/LY TEMPS AND TDS A BIT.
A WEAK COLD FRONT IS MAKING ITS WAY EAST ACROSS THE CWFA ATTM WITH
LITTLE FANFARE. THERE IS A WEAK LINE OF -SHRA MOVING EAST ACROSS THE
NRN FOOTHILLS AND WILL EXPECT THIS TO CONTINUE EAST THROUGH THE
MORNING REMAINING IN THE NW PIEDMONT. THE HRRR IS HANDLING THIS
SITUATION MUCH BETTER THAN THE OTHER HIRES MODELS AND THERE IS NO
NEED TO JUMP OUTSIDE OF ITS GENERAL GUIDANCE. POPS HAVE BEEN ADJ
DOWN INTO THE ISOL RANGE WHICH SHOULD WORK OUT PRETTY GOOD.
THE ATMOS WILL REMAIN WEAKLY FORCED THROUGH THE AFTERNOON AS THE
MASSIVE CLOSED LOW SLOWLY BEGINS TO BREAK DOWN AND PULL NE. THIS
WILL GENERALLY LEAVE THE FCST AREA IN A MODEST SUBSIDENCE REGIME
SLOWING THE SFC FRONT AND WASHING IT OUT. THUS...THERE WONT BE MUCH
OF A WIND SHIFT WITH THE TROF AXIS. THERE WILL BE A GOOD GUST
POTENTIAL AS MIXING ALLOWS 20-25 KT MOMENTUM TRANSFERS. MAX TEMPS
WILL BE TRICKY AS A TIGHT LLVL THICKNESS GRADIENT MOVES IN...BUT
BECOMES MODIFIED WARMER WITH THE CONTINUED S/LY FLOW...ESP OUTSIDE
THE MTNS. THE GFS IS MORE AGGRESSIVE THAN THE NAM WITH THIS WARMING
MODIFICATION...SO A BLEND WAS TAKEN ALONG WITH A BLEND OF BIAS
CORRECTION...WHICH GIVES MAX TEMPS A DEGREE OR TWO ABOVE NORMAL MOST
LOCALS. THIS COULD BE A TAD LOW THO IN GOOD INSOLATION.
OVERNIGHT...THE PRESSURE GRADIENT BEGINS TO RELAX AS HIGH PRESSURE
MOVES IN FROM THE SW AND THE AREA BECOMES LESS INFLUENCED BY THE
WEAKENING ULVL LOW. SKY COVER IS NOT WHOLLY CERTAIN ATTM...BUT MOST
INDICATIONS ARE A CI DECK WILL MOVE IN AND OFFSET MAX COOLING BY A
FEW DEGREES. EVEN WITH THE LOWER MTN THICKNESSES...CLOUD COVER WILL
MOSTLY ELIMINATE A FROST CONCERN EVEN ACROSS THE MTN TOPS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 130 AM THURSDAY...THE SHORT TERM PERIOD INITIALIZES FRIDAY
MORNING WITH A RATHER PROGRESSIVE UPPER TROF SLIDING EAST ACROSS
THE MID MISSISSIPPI RIVER VALLEY AND WEAK SURFACE HIGH PRESSURE
BUILDING INTO THE MIDSOUTH. GUIDANCE CONTINUES TO AGREE ON A QUASI
STATIONARY FRONTAL BOUNDARY LYING ACROSS THE SOUTHEASTERN ATLANTIC
COASTLINE WITH A SURFACE WAVE DEVELOPING OVER THE NORTHERN GULF.
THE GFS SEEMS TO BE THE OUTLIER WITH ITS SOLUTION INDICATING THE
SURFACE WAVE SLIDING NORTHEAST SPREADING SHOWERS ACROSS THE SOUTHERN
TWO THIRDS OF THE FORECAST AREA. THE ECMWF/NAM/CMC KEEP THE WAVE
TIED CLOSER TO THE COASTLINE RESULTING IN A DRY FORECAST FOR
NORTHEAST GA AND THE WESTERN CAROLINAS. THAT SAID...ALL SOLUTIONS
CONVERGE ON SUFFICIENT UPPER DIVERGENCE TO SUPPORT MOSTLY CLOUDY
SKIES THANKS TO PROXIMITY OF THE RIGHT REAR ENTRANCE REGION OF AN
EJECTING UPPER JET MAX. BEYOND THAT...THE PATTERN TRANSITIONS
SIGNIFICANTLY WITH A BROAD UPPER TROF SLIDING EAST TAKING ROOT OVER
THE EAST/CENTRAL CONUS THROUGH THE REMAINDER OF THE SHORT TERM
PERIOD. THIS WILL LEAD TO DECREASING CLOUDINESS AND THE START OF A
GRADUAL WARMING TREND. THUS THE SHORT TERM FORECAST WILL FEATURE NO
MENTIONABLE POPS WITH TEMPERATURES ON FRIDAY REMAINING 3-5 DEGREES
BELOW NORMAL BEFORE WARMING TO AROUND NORMAL FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
SUNDAY MORNING WITH DEEP LAYER RIDGING PREVAILING ACROSS THE
SOUTHEAST. A BROAD UPPER RIDGE WILL CONTINUE SLIDING EAST WHILE
SURFACE HIGH PRESSURE REMAINS CENTERED OVER THE GULF OF MEXICO. A
SURFACE CYCLONE OVER EASTERN QUEBEC WILL SLIDE THROUGH THE NORTHEAST
SPREADING A WEAK COLD FRONTAL BOUNDARY SOUTHWARD INTO THE OHIO
VALLEY ON SUNDAY. MEANWHILE...WEAK WAA ACROSS THE LOWER/MID
MISSISSIPPI RIVER VALLEY WILL PRESENT A ZONE OF CONVERGENCE ALONG
THE DESCENDING BRANCH OF THE UPPER TROF. GUIDANCE HINTS AT
POTENTIAL ACTIVATION ALONG THIS BOUNDARY LEADING SHOWERS/MCS
SPILLING EAST INTO THE CENTRAL APPALACHIANS. HOWEVER...THIS
ACTIVITY LOOKS TO REMAIN JUST NORTH OF THE FORECAST AREA THEREFORE
DECIDED NOT TO INCLUDE ANY MENTIONABLE POPS AT THIS RANGE. BEYOND
THAT...THE UPPER RIDGE ADVECTS FURTHER EAST WITH A SERIES OF
POTENTIAL EVENING/NOCTURNAL MCS EVENTS PASSING NORTH OF THE FORECAST
AREA THROUGH THE REMAINDER OF THE PERIOD. THE ABOVE MENTIONED GULF
SURFACE RIDGE WILL TRANSITION TO A BERMUDA TYPE HIGH BY MIDWEEK
SETTING UP THE RETURN OF LOW LEVEL WARM ADVECTION LEADING TO
TEMPERATURES EACH AFTERNOON BEING AN ORDER OF MAGNITUDE ABOVE
NORMAL.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AT KCLT...THREAT OF ANY FLIGHT RESTRICTIONS HAS ENDED. HOWEVER...
SOME SCT LOW VFR CANNOT BE RULED OUT THIS AFTERNOON WITH CONTINUED
MAINLY HIGH CLOUDS. STILL EXPECT GUSTY SW WIND THIS AFTERNOON. WINDS
DIMINISH THIS EVENING WITH INCREASING MID AND HIGH CLOUDS OVERNIGHT.
ELSEWHERE...SIMILAR CONDITIONS AS KCLT. KAVL THE EXCEPTION WITH
GUSTY NLY WIND THIS AFTERNOON.
OUTLOOK...DRYING CONDITIONS WITH NO RESTRICTIONS EXPECTED FRI
THROUGH MON. CANNOT RULE OUT SOME MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-14Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CDG
NEAR TERM...RWH/SBK
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...RWH/SBK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
626 AM EDT THU MAY 1 2014
.SYNOPSIS...
A COLD FRONT WILL EXIT THE REGION TO THE SOUTHEAST ON THURSDAY
MORNING WITH COOLER/DRIER HIGH PRESSURE BUILDING THROUGH THE
REMAINDER OF THE WORK WEEK. TEMPERATURES WILL WARM THROUGH THE
WEEKEND AND INTO NEXT WEEK AS AN UPPER LEVEL RIDGE SLIDES EAST
LEADING TO MORE SEASONABLE WEATHER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM EDT...NO NEED TO MAKE ANY MAJOR CHANGES TO THE FCST.
UPPER CI CONTINUES TO OVERSPREAD LLVL STCU AT MOST LOCALES. SLOW
MOVING COLD FRONT HAS REACHED THE ERN HALF OF THE CWFA WITH NO UPPER
SUPPORT...THUS LITTLE PRECIP EXCEPT FOR A COUPLE WEAK LINES OF -SHRA
OVER THE ERN ZONES. CURRENT SLIGHT POPS HAVE THIS IN CHECK. TEMPS
HAVE BEEN HELD UP WITH CLOUD COVER / MIXING...WITH LOW END GUSTS
SHOWING UP AT KCLT. TDDS ARE REMAINING LARGE ENUF TO PRECLUDE A FG
THREAT WITH SOME LOW LYING AREAS IN THE NRN FTHILLS BEING THE
EXCEPTION. WILL ADJ HR/LY TEMPS AND TDS A BIT.
A WEAK COLD FRONT IS MAKING ITS WAY EAST ACROSS THE CWFA ATTM WITH
LITTLE FANFARE. THERE IS A WEAK LINE OF -SHRA MOVING EAST ACROSS THE
NRN FOOTHILLS AND WILL EXPECT THIS TO CONTINUE EAST THROUGH THE
MORNING REMAINING IN THE NW PIEDMONT. THE HRRR IS HANDLING THIS
SITUATION MUCH BETTER THAN THE OTHER HIRES MODELS AND THERE IS NO
NEED TO JUMP OUTSIDE OF ITS GENERAL GUIDANCE. POPS HAVE BEEN ADJ
DOWN INTO THE ISOL RANGE WHICH SHOULD WORK OUT PRETTY GOOD.
THE ATMOS WILL REMAIN WEAKLY FORCED THROUGH THE AFTERNOON AS THE
MASSIVE CLOSED LOW SLOWLY BEGINS TO BREAK DOWN AND PULL NE. THIS
WILL GENERALLY LEAVE THE FCST AREA IN A MODEST SUBSIDENCE REGIME
SLOWING THE SFC FRONT AND WASHING IT OUT. THUS...THERE WONT BE MUCH
OF A WIND SHIFT WITH THE TROF AXIS. THERE WILL BE A GOOD GUST
POTENTIAL AS MIXING ALLOWS 20-25 KT MOMENTUM TRANSFERS. MAX TEMPS
WILL BE TRICKY AS A TIGHT LLVL THICKNESS GRADIENT MOVES IN...BUT
BECOMES MODIFIED WARMER WITH THE CONTINUED S/LY FLOW...ESP OUTSIDE
THE MTNS. THE GFS IS MORE AGGRESSIVE THAN THE NAM WITH THIS WARMING
MODIFICATION...SO A BLEND WAS TAKEN ALONG WITH A BLEND OF BIAS
CORRECTION...WHICH GIVES MAX TEMPS A DEGREE OR TWO ABOVE NORMAL MOST
LOCALS. THIS COULD BE A TAD LOW THO IN GOOD INSOLATION.
OVERNIGHT...THE PRESSURE GRADIENT BEGINS TO RELAX AS HIGH PRESSURE
MOVES IN FROM THE SW AND THE AREA BECOMES LESS INFLUENCED BY THE
WEAKENING ULVL LOW. SKY COVER IS NOT WHOLLY CERTAIN ATTM...BUT MOST
INDICATIONS ARE A CI DECK WILL MOVE IN AND OFFSET MAX COOLING BY A
FEW DEGREES. EVEN WITH THE LOWER MTN THICKNESSES...CLOUD COVER WILL
MOSTLY ELIMINATE A FROST CONCERN EVEN ACROSS THE MTN TOPS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 130 AM THURSDAY...THE SHORT TERM PERIOD INITIALIZES FRIDAY
MORNING WITH A RATHER PROGRESSIVE UPPER TROF SLIDING EAST ACROSS
THE MID MISSISSIPPI RIVER VALLEY AND WEAK SURFACE HIGH PRESSURE
BUILDING INTO THE MIDSOUTH. GUIDANCE CONTINUES TO AGREE ON A QUASI
STATIONARY FRONTAL BOUNDARY LYING ACROSS THE SOUTHEASTERN ATLANTIC
COASTLINE WITH A SURFACE WAVE DEVELOPING OVER THE NORTHERN GULF.
THE GFS SEEMS TO BE THE OUTLIER WITH ITS SOLUTION INDICATING THE
SURFACE WAVE SLIDING NORTHEAST SPREADING SHOWERS ACROSS THE SOUTHERN
TWO THIRDS OF THE FORECAST AREA. THE ECMWF/NAM/CMC KEEP THE WAVE
TIED CLOSER TO THE COASTLINE RESULTING IN A DRY FORECAST FOR
NORTHEAST GA AND THE WESTERN CAROLINAS. THAT SAID...ALL SOLUTIONS
CONVERGE ON SUFFICIENT UPPER DIVERGENCE TO SUPPORT MOSTLY CLOUDY
SKIES THANKS TO PROXIMITY OF THE RIGHT REAR ENTRANCE REGION OF AN
EJECTING UPPER JET MAX. BEYOND THAT...THE PATTERN TRANSITIONS
SIGNIFICANTLY WITH A BROAD UPPER TROF SLIDING EAST TAKING ROOT OVER
THE EAST/CENTRAL CONUS THROUGH THE REMAINDER OF THE SHORT TERM
PERIOD. THIS WILL LEAD TO DECREASING CLOUDINESS AND THE START OF A
GRADUAL WARMING TREND. THUS THE SHORT TERM FORECAST WILL FEATURE NO
MENTIONABLE POPS WITH TEMPERATURES ON FRIDAY REMAINING 3-5 DEGREES
BELOW NORMAL BEFORE WARMING TO AROUND NORMAL FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
SUNDAY MORNING WITH DEEP LAYER RIDGING PREVAILING ACROSS THE
SOUTHEAST. A BROAD UPPER RIDGE WILL CONTINUE SLIDING EAST WHILE
SURFACE HIGH PRESSURE REMAINS CENTERED OVER THE GULF OF MEXICO. A
SURFACE CYCLONE OVER EASTERN QUEBEC WILL SLIDE THROUGH THE NORTHEAST
SPREADING A WEAK COLD FRONTAL BOUNDARY SOUTHWARD INTO THE OHIO
VALLEY ON SUNDAY. MEANWHILE...WEAK WAA ACROSS THE LOWER/MID
MISSISSIPPI RIVER VALLEY WILL PRESENT A ZONE OF CONVERGENCE ALONG
THE DESCENDING BRANCH OF THE UPPER TROF. GUIDANCE HINTS AT
POTENTIAL ACTIVATION ALONG THIS BOUNDARY LEADING SHOWERS/MCS
SPILLING EAST INTO THE CENTRAL APPALACHIANS. HOWEVER...THIS
ACTIVITY LOOKS TO REMAIN JUST NORTH OF THE FORECAST AREA THEREFORE
DECIDED NOT TO INCLUDE ANY MENTIONABLE POPS AT THIS RANGE. BEYOND
THAT...THE UPPER RIDGE ADVECTS FURTHER EAST WITH A SERIES OF
POTENTIAL EVENING/NOCTURNAL MCS EVENTS PASSING NORTH OF THE FORECAST
AREA THROUGH THE REMAINDER OF THE PERIOD. THE ABOVE MENTIONED GULF
SURFACE RIDGE WILL TRANSITION TO A BERMUDA TYPE HIGH BY MIDWEEK
SETTING UP THE RETURN OF LOW LEVEL WARM ADVECTION LEADING TO
TEMPERATURES EACH AFTERNOON BEING AN ORDER OF MAGNITUDE ABOVE
NORMAL.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AT KCLT...MVFR CIGS COULD DEVELOP THIS AM...BUT MOST LIKELY WILL
PERSIST VFR AS ULVL CLOUDS CROSS AND REMAIN RELATIVELY THIN. WINDS
WILL CONTINUE SW/LY IN CROSS GRADIENT FLOW WITH MODERATE GUST
POTENTIAL THIS AFTERNOON...SHIFTING WEAK W/LY LATE IN THE TAF
PERIOD.
ELSEWHERE...ALL TAF SITES COULD GO IN AND OUT OF VFR/MVFR CIGS OVER
THE NEXT FEW HRS WITH VFR MOST LIKELY. KAVL SHOULD SCT OUT WITH
EARLIER FROPA. IMPROVING CONDS DEVELOP FAIRLY QUICKLY AFT SUNRISE
WITH SCT/BKN CI THIS AFTERNOON. WINDS WILL BE CHANNELED NW/LY AT
KAVL DURING THE DAY WITH LOWER END GUSTS THERE AND AT KHKY...WHILE
THE PIEDMONT SITES WILL SEE MORE HEATING/MIXING LEADING TO MODERATE
GUSTS THIS AFTERNOON.
OUTLOOK...DRYING CONDITIONS WITH NO RESTRICTIONS EXPECTED FRI
THROUGH MON. CANNOT RULE OUT SOME MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
10-16Z 16-22Z 22-04Z 04-10Z
KCLT HIGH 89% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 92% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 89% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CDG
NEAR TERM...SBK
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...SBK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
305 AM EDT THU MAY 1 2014
.SYNOPSIS...
A COLD FRONT WILL EXIT THE REGION TO THE SOUTHEAST ON THURSDAY
MORNING WITH COOLER/DRIER HIGH PRESSURE BUILDING THROUGH THE
REMAINDER OF THE WORK WEEK. TEMPERATURES WILL WARM THROUGH THE
WEEKEND AND INTO NEXT WEEK AS AN UPPER LEVEL RIDGE SLIDES EAST
LEADING TO MORE SEASONABLE WEATHER.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEAK COLD FRONT IS MAKING ITS WAY EAST ACROSS THE CWFA ATTM WITH
LITTLE FANFARE. THERE IS A WEAK LINE OF -SHRA MOVING EAST ACROSS THE
NRN FOOTHILLS AND WILL EXPECT THIS TO CONTINUE EAST THROUGH THE
MORNING REMAINING IN THE NW PIEDMONT. THE HRRR IS HANDLING THIS
SITUATION MUCH BETTER THAN THE OTHER HIRES MODELS AND THERE IS NO
NEED TO JUMP OUTSIDE OF ITS GENERAL GUIDANCE. POPS HAVE BEEN ADJ
DOWN INTO THE ISOL RANGE WHICH SHOULD WORK OUT PRETTY GOOD.
THE ATMOS WILL REMAIN WEAKLY FORCED THROUGH THE AFTERNOON AS THE
MASSIVE CLOSED LOW SLOWLY BEGINS TO BREAK DOWN AND PULL NE. THIS
WILL GENERALLY LEAVE THE FCST AREA IN A MODEST SUBSIDENCE REGIME
SLOWING THE SFC FRONT AND WASHING IT OUT. THUS...THERE WONT BE MUCH
OF A WIND SHIFT WITH THE TROF AXIS. THERE WILL BE A GOOD GUST
POTENTIAL AS MIXING ALLOWS 20-25 KT MOMENTUM TRANSFERS. MAX TEMPS
WILL BE TRICKY AS A TIGHT LLVL THICKNESS GRADIENT MOVES IN...BUT
BECOMES MODIFIED WARMER WITH THE CONTINUED S/LY FLOW...ESP OUTSIDE
THE MTNS. THE GFS IS MORE AGGRESSIVE THAN THE NAM WITH THIS WARMING
MODIFICATION...SO A BLEND WAS TAKEN ALONG WITH A BLEND OF BIAS
CORRECTION...WHICH GIVES MAX TEMPS A DEGREE OR TWO ABOVE NORMAL MOST
LOCALS. THIS COULD BE A TAD LOW THO IN GOOD INSOLATION.
OVERNIGHT...THE PRESSURE GRADIENT BEGINS TO RELAX AS HIGH PRESSURE
MOVES IN FROM THE SW AND THE AREA BECOMES LESS INFLUENCED BY THE
WEAKENING ULVL LOW. SKY COVER IS NOT WHOLLY CERTAIN ATTM...BUT MOST
INDICATIONS ARE A CI DECK WILL MOVE IN AND OFFSET MAX COOLING BY A
FEW DEGREES. EVEN WITH THE LOWER MTN THICKNESSES...CLOUD COVER WILL
MOSTLY ELIMINATE A FROST CONCERN EVEN ACROSS THE MTN TOPS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 130 AM THURSDAY...THE SHORT TERM PERIOD INITIALIZES FRIDAY
MORNING WITH A RATHER PROGRESSIVE UPPER TROF SLIDING EAST ACROSS
THE MID MISSISSIPPI RIVER VALLEY AND WEAK SURFACE HIGH PRESSURE
BUILDING INTO THE MIDSOUTH. GUIDANCE CONTINUES TO AGREE ON A QUASI
STATIONARY FRONTAL BOUNDARY LYING ACROSS THE SOUTHEASTERN ATLANTIC
COASTLINE WITH A SURFACE WAVE DEVELOPING OVER THE NORTHERN GULF.
THE GFS SEEMS TO BE THE OUTLIER WITH ITS SOLUTION INDICATING THE
SURFACE WAVE SLIDING NORTHEAST SPREADING SHOWERS ACROSS THE SOUTHERN
TWO THIRDS OF THE FORECAST AREA. THE ECMWF/NAM/CMC KEEP THE WAVE
TIED CLOSER TO THE COASTLINE RESULTING IN A DRY FORECAST FOR
NORTHEAST GA AND THE WESTERN CAROLINAS. THAT SAID...ALL SOLUTIONS
CONVERGE ON SUFFICIENT UPPER DIVERGENCE TO SUPPORT MOSTLY CLOUDY
SKIES THANKS TO PROXIMITY OF THE RIGHT REAR ENTRANCE REGION OF AN
EJECTING UPPER JET MAX. BEYOND THAT...THE PATTERN TRANSITIONS
SIGNIFICANTLY WITH A BROAD UPPER TROF SLIDING EAST TAKING ROOT OVER
THE EAST/CENTRAL CONUS THROUGH THE REMAINDER OF THE SHORT TERM
PERIOD. THIS WILL LEAD TO DECREASING CLOUDINESS AND THE START OF A
GRADUAL WARMING TREND. THUS THE SHORT TERM FORECAST WILL FEATURE NO
MENTIONABLE POPS WITH TEMPERATURES ON FRIDAY REMAINING 3-5 DEGREES
BELOW NORMAL BEFORE WARMING TO AROUND NORMAL FOR SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 200 AM EDT THURSDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
SUNDAY MORNING WITH DEEP LAYER RIDGING PREVAILING ACROSS THE
SOUTHEAST. A BROAD UPPER RIDGE WILL CONTINUE SLIDING EAST WHILE
SURFACE HIGH PRESSURE REMAINS CENTERED OVER THE GULF OF MEXICO. A
SURFACE CYCLONE OVER EASTERN QUEBEC WILL SLIDE THROUGH THE NORTHEAST
SPREADING A WEAK COLD FRONTAL BOUNDARY SOUTHWARD INTO THE OHIO
VALLEY ON SUNDAY. MEANWHILE...WEAK WAA ACROSS THE LOWER/MID
MISSISSIPPI RIVER VALLEY WILL PRESENT A ZONE OF CONVERGENCE ALONG
THE DESCENDING BRANCH OF THE UPPER TROF. GUIDANCE HINTS AT
POTENTIAL ACTIVATION ALONG THIS BOUNDARY LEADING SHOWERS/MCS
SPILLING EAST INTO THE CENTRAL APPALACHIANS. HOWEVER...THIS
ACTIVITY LOOKS TO REMAIN JUST NORTH OF THE FORECAST AREA THEREFORE
DECIDED NOT TO INCLUDE ANY MENTIONABLE POPS AT THIS RANGE. BEYOND
THAT...THE UPPER RIDGE ADVECTS FURTHER EAST WITH A SERIES OF
POTENTIAL EVENING/NOCTURNAL MCS EVENTS PASSING NORTH OF THE FORECAST
AREA THROUGH THE REMAINDER OF THE PERIOD. THE ABOVE MENTIONED GULF
SURFACE RIDGE WILL TRANSITION TO A BERMUDA TYPE HIGH BY MIDWEEK
SETTING UP THE RETURN OF LOW LEVEL WARM ADVECTION LEADING TO
TEMPERATURES EACH AFTERNOON BEING AN ORDER OF MAGNITUDE ABOVE
NORMAL.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
AT KCLT...SEEING LESS AND LESS CHANCES FOR PRECIP DEVELOPING ALONG
THE WEAK FROPA THIS MORNING. MVFR CIGS ARE LIKELY TO CONTINUE
THROUGH DAYBREAK WITH ULVL CLOUDS REMAINING RELATIVELY THIN...AND A
DIP INTO IFR IS POSSIBLE AS THE FRONT WASHES OUT OVER THE AREA. WILL
MONITOR AND AMD AS NEEDED. WINDS WILL REMAIN SW/LY IN CROSS GRADIENT
FLOW WITH MODERATE GUST POTENTIAL THIS AFTERNOON...SHIFTING WEAK
W/LY LATE IN THE TAF PERIOD.
ELSEWHERE...ALL TAF SITES SHOULD GO IN AND OUT OF VFR/MVFR CIGS OVER
THE NEXT FEW HRS...WITH LIKELY MVFR CONDS AT DAYBREAK. KAVL SHOULD
SCT OUT WITH EARLIER FROPA. IMPROVING CONDS DEVELOP FAIRLY QUICKLY
AFT SUNRISE WITH SCT/BKN CI THIS AFTERNOON. WINDS WILL BE CHANNELED
NW/LY AT KAVL DURING THE DAY WITH LOWER END GUSTS THERE AND AT
KHKY...WHILE THE PIEDMONT SITES WILL SEE MORE HEATING/MIXING LEADING
TO MODERATE GUSTS THIS AFTERNOON.
OUTLOOK...DRYING CONDITIONS WITH NO RESTRICTIONS EXPECTED FRI
THROUGH MON. CANNOT RULE OUT SOME MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-07Z
KCLT HIGH 83% HIGH 94% HIGH 100% HIGH 100%
KGSP MED 79% HIGH 100% HIGH 100% HIGH 100%
KAVL MED 74% HIGH 100% HIGH 100% HIGH 100%
KHKY MED 75% HIGH 99% HIGH 100% HIGH 100%
KGMU MED 74% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 85% HIGH 99% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CDG
NEAR TERM...SBK
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...SBK
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
650 PM MDT FRI MAY 2 2014
.UPDATE...
ISSUED AT 644 PM MDT FRI MAY 2 2014
AMS HAS BECOME QUITE STABLE (SEE 00Z KUNR SOUNDING) WITH SFC HIGH
PRESSURE BUILDING INTO WRN SD SO HAVE REMOVED THUNDER FROM THE
FCST...WHILE ALSO CUTTING BACK ON POPS. REST OF FCST LARGELY
UNCHANGED.
&&
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 216 PM MDT FRI MAY 2 2014
20Z SURFACE ANALYSIS SHOWED COOL FRONT HAD STALLED FROM CENTRAL
MT INTO WESTERN NE INTO NORTHWEST IA. WEAK HIGH PRESSURE BUILDING
BEHIND IT. SHORTWAVE ENERGY OVER NORTHEAST MT/ND SUPPORTING BAND
OF POST FRONTAL -SHRA FROM EASTERN MT INTO CENTRAL SD...BUT HAVING
A BIT OF TROUBLE MAINTAINING THEMSELVES GIVEN DRIER AIR OVER THE
CWA. ACTIVITY MAY YET EXPAND PER LOCAL WRF/18Z RAP LATE THIS
AFTERNOON/EARLY THIS EVENING AS WEAK MLCAPE DEVELOPS AND SHORTWAVE
ENERGY RUSHES PAST. LOWS TONIGHT WILL BE NEAR GUIDANCE.
SATURDAY...FRONTAL BOUNDARY WILL MOVE LITTLE AS LOW LEVEL BAROCLINIC
ZONE REMAINS STRETCHED FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA.
COUPLE OF SHORTWAVES WILL MOVE NORTH OF CWA BRINGING JUST ENOUGH
FORCING FOR A FEW -SHRA/DIURNALLY DRIVEN -TSRA GIVEN WEAK MLCAPE.
ACTIVITY WILL HAVE BEST CHANCE OVER THE FAR NORTH SATURDAY NIGHT AS
LOW LEVEL FLOW BECOMES UPSLOPE AND BEST WAVE MOVES ACROSS ND.
TEMPERATURES WILL BE TRICKY GIVEN CLOUD COVER/TIGHT ISOTHERMS...SO
TRENDED COOLISH IN THE NORTH AND WARMISH IN THE SOUTH/WEST.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 216 PM MDT FRI MAY 2 2014
WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A
VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP
CHANCES TO THE AREA. FOR THE MID-WEEK...A SPLIT FLOW TROF IS
PROGGED TO CROSS THE ROCKIES WITH STRONGER SWRLY FLOW
DEVELOPING...BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. DRIER
WEATHER MAY RETURN LATER IN THE WORK WEEK...BUT WILL LEAVE SLIGHT
CHANCE POPS FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 649 PM MDT FRI MAY 2 2014
ISOLD -SHRA ARE EXPECTED THROUGH THIS EVENING. ISOLD -SHRA WILL
BE POSSIBLE AGAIN LATE TONIGHT THROUGH THE DAY TOMORROW ACROSS
PORTIONS OF NE WY TO NW SD AND THE BLKHLS AREA. ISOLD -TSRA ARE
POSSIBLE IN THE AFTERNOON. LCL MVFR CONDITIONS WILL BE POSSIBLE IN
AND NEAR ANY PRECIP. THERE IS ALSO A CHANCE OF MVFR STRATUS
DEVELOPING ACROSS PORTIONS OF NERN WY AND NWRN SD LATE TONIGHT AND
SATURDAY MORNING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
647 PM MDT FRI MAY 2 2014
.UPDATE...
ISSUED AT 644 PM MDT FRI MAY 2 2014
AMS HAS BECOME QUITE STABLE (SEE 00Z KUNR SOUNDING) WITH SFC HIGH
PRESSURE BUILDING INTO WRN SD SO HAVE REMOVED THUNDER FROM THE
FCST...WHILE ALSO CUTTING BACK ON POPS. REST OF FCST LARGELY
UNCHANGED.
&&
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 216 PM MDT FRI MAY 2 2014
20Z SURFACE ANALYSIS SHOWED COOL FRONT HAD STALLED FROM CENTRAL
MT INTO WESTERN NE INTO NORTHWEST IA. WEAK HIGH PRESSURE BUILDING
BEHIND IT. SHORTWAVE ENERGY OVER NORTHEAST MT/ND SUPPORTING BAND
OF POST FRONTAL -SHRA FROM EASTERN MT INTO CENTRAL SD...BUT HAVING
A BIT OF TROUBLE MAINTAINING THEMSELVES GIVEN DRIER AIR OVER THE
CWA. ACTIVITY MAY YET EXPAND PER LOCAL WRF/18Z RAP LATE THIS
AFTERNOON/EARLY THIS EVENING AS WEAK MLCAPE DEVELOPS AND SHORTWAVE
ENERGY RUSHES PAST. LOWS TONIGHT WILL BE NEAR GUIDANCE.
SATURDAY...FRONTAL BOUNDARY WILL MOVE LITTLE AS LOW LEVEL BAROCLINIC
ZONE REMAINS STRETCHED FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA.
COUPLE OF SHORTWAVES WILL MOVE NORTH OF CWA BRINGING JUST ENOUGH
FORCING FOR A FEW -SHRA/DIURNALLY DRIVEN -TSRA GIVEN WEAK MLCAPE.
ACTIVITY WILL HAVE BEST CHANCE OVER THE FAR NORTH SATURDAY NIGHT AS
LOW LEVEL FLOW BECOMES UPSLOPE AND BEST WAVE MOVES ACROSS ND.
TEMPERATURES WILL BE TRICKY GIVEN CLOUD COVER/TIGHT ISOTHERMS...SO
TRENDED COOLISH IN THE NORTH AND WARMISH IN THE SOUTH/WEST.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 216 PM MDT FRI MAY 2 2014
WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A
VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP
CHANCES TO THE AREA. FOR THE MID-WEEK...A SPLIT FLOW TROF IS
PROGGED TO CROSS THE ROCKIES WITH STRONGER SWRLY FLOW
DEVELOPING...BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. DRIER
WEATHER MAY RETURN LATER IN THE WORK WEEK...BUT WILL LEAVE SLIGHT
CHANCE POPS FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 401 PM MDT FRI MAY 2 2014
SCT -SHRA WITH ISOLD -TSRA ARE EXPECTED THROUGH THIS EVENING.
ISOLD -SHRA WILL BE POSSIBLE LATE TONIGHT THROUGH THE DAY TOMORROW
ACROSS PORTIONS OF NE WY TO NW SD AND THE BLKHLS AREA. ISOLD -TSRA
ARE POSSIBLE IN THE AFTERNOON. LCL MVFR CONDITIONS WILL BE
POSSIBLE IN AND NEAR ANY PRECIP. THERE IS ALSO A CHANCE OF MVFR
STRATUS DEVELOPING ACROSS PORTIONS OF NERN WY AND NWRN SD LATE
TONIGHT AND SATURDAY MORNING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 216 PM CDT THU MAY 1 2014
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN UPPER LEVEL
LOW PRESSURE SYSTEM MOVING ACROSS CENTRAL LAKE MICHIGAN EARLY THIS
AFTERNOON. LAGGING BEHIND THIS UPPER LOW IS A SURFACE TROUGH WHICH
EXTENDS ACROSS NORTHEAST AND CENTRAL WISCONSIN. MOST THE
PRECIPITATION SO FAR TODAY HAS OCCURRED OVER NORTHEAST/NORTH-CENTRAL
AND CENTRAL WISCONSIN THOUGH SHOWERS ARE STARTING TO REDEVELOP
ACROSS THE FOX VALLEY AND EAST-CENTRAL WISCONSIN LAKE SHORE.
SHOWERS AND DRIZZLE EXTEND ALL THE WAY TO THE MINNESOTA BORDER...SO
WILL TAKE AWHILE FOR DRY CONDITIONS TO RESUME. WITH SHOWERS
REDEVELOPING...WILL HAVE LIKELY SHOWERS FOR THE WHOLE FORECAST AREA
THROUGH EARLY THIS EVENING. CLEARING SKIES DO NOT BEGIN UNTIL YOU
REACH NORTH DAKOTA AND MANITOBA...BUT THE NEXT SHORTWAVE IS ALREADY
MOVING INTO THIS AREA...AND POISED TO MOVE INTO THE REGION
TOMORROW. PRECIP CHANCES REMAIN THE MAIN FORECAST CONCERN IN THE
SHORT TERM.
TONIGHT...THE PESKY UPPER LOW WILL FINALLY EXIT TO THE EASTERN GREAT
LAKES TONIGHT THANKS TO KICKER ENERGY DIVING SOUTHEAST ACROSS
SOUTH-CENTRAL CANADA. WITH SHOWERS EXTENDING BACK TO THE MINNESOTA
BORDER AND A SURFACE TROUGH STILL TO MOVE THROUGH THIS
EVENING...PROGGED SOUNDINGS REMAIN SUFFICIENTLY SATURATED TO INCLUDE
SHOWERS IN THE FORECAST THROUGH MIDNIGHT. DRYING ALOFT DOES
PROGRESSIVELY OCCUR AFTER MIDNIGHT SO THINK WE COULD FINALLY SEE A
DRY PERIOD TAKE PLACE LATE TONIGHT. SKIES SHOULD REMAIN MOSTLY CLOUDY
THROUGH THE NIGHT HOWEVER...WITH A LOW OVERCAST DECK GRADUALLY
RISING AFTER MIDNIGHT. LOWS IN THE MID 30S TO LOW 40S.
FRIDAY...DECENT SHORTWAVE ENERGY WILL CONTINUE TO MOVE SOUTHEAST
INTO THE NORTHERN MISSISSIPPI VALLEY BY 18Z AND CENTRAL WISCONSIN BY
00Z SATURDAY. LARGE SCALE FORCING IN THE FORM OF DPVA AND UPPER
DIVERGENCE IN THE LEFT FRONT QUAD OF A JET STREAK WILL INCREASE
DURING THE AFTERNOON. SLOWED DOWN TIMING OF PRECIP CHANCES A LITTLE
AND ONLY BRING A SMALL CHANCE OF SHOWERS INTO WESTERN SECTIONS OF
THE CWA PRIOR TO 18Z. THEN WILL INCREASE POPS INTO THE LIKELY RANGE
EAST OF THE LAKE SHORE BY MID AFTERNOON. LOOKING AT MODIFIED
SOUNDINGS FOR TOMORROW AFTERNOON...ML CAPES ARE A LITTLE HIGHER THAN
DEPICTED YESTERDAY...BUT STILL STRUGGLE TO SQUEAK OUT 50-75 J/KG OF
INSTABILITY. INSTABILITY IS BETTER OVER SOUTHWEST WISCONSIN
COMPARED TO OUR REGION...SO THINK WILL LEAVE OUT A MENTION OF
THUNDER. HIGH TEMPS SHOULD RISE INTO THE LOW TO MID 50S BEFORE THE
RAIN SHOWERS ARRIVE.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 216 PM CDT THU MAY 1 2014
SIGNIFICANT PATTERN CHANGE DURING THE PERIOD AS UPPER FLOW ACROSS
THE CENTRAL U.S. GOES FROM NW TO SW.
EARLY IN PERIOD...STILL DEALING WITH UPPER LOW OVER SE CANADA AND
ONE MORE WEAK DISTURBANCE. ON SATURDAY...MARGINAL INSTABILITY
SHOULD BE SUFFICIENT FOR MID-DAY OR AFTERNOON SHOWERS. BRIEF DRY
PERIOD THEN AS SFC RIDGE MOVES ACROSS STATE.
NEXT SYSTEM MOVES TOWARD REGION MIDWEEK. GFS AND ECMWF IN GENERAL
AGREEMENT ON MOVEMENT AND LOCATION...THOUGH GFS A BIT FASTER.
WARM FRONT MAKES NORTH PUSH INTO STATE ON WED. ELEVATED CONVECTION
EXPECTED AS RIPPLES IN SW FLOW MOVE OVER LOW-LEVEL CONVERGENCE
ALONG FRONT. FRONTAL POSITION WILL HAVE SIGNIFICANT IMPACT ON
TEMPS...ESP NEXT THURS. WILL SIDE WITH SLOWER ECMWF FOR NOW...AS
COLD LAKE MICH SHOULD SLOW DOWN NORTH PUSH...AT LEAST INITIALLY.
TEMP FORECAST FOR THE MAJORITY OF THE LONG TERM A BLEND OF BEST
PERFORMING GUIDANCE.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1226 PM CDT THU MAY 1 2014
SLOW MOVING PESKY UPPER LOW WILL FINALLY DEPART THE REGION TO THE
EAST TONIGHT. BUT UNTIL THIS OCCURS...SHOWERS AND DRIZZLE WILL BE
WIDESPREAD ACROSS CENTRAL...NORTH-CENTRAL AND FAR NE WISCONSIN
THROUGH LATE AFTERNOON AND POSSIBLY INTO THIS EVENING AS WELL. WITH
THE SHOWERS/DRIZZLE...CIGS/VSBYS WILL FALL INTO THE IFR RANGE AT
TIMES. THE FOX VALLEY AND LAKE SHORE AREAS WILL SEE ONLY SPOTTY
SHOWERS...AND CIGS ARE LIKELY TO REMAIN IN THE VFR AND MVFR RANGE.
CIGS TO REMAIN MVFR AND IFR THROUGH LATE TONIGHT OR EARLY TOMORROW
MORNING BEFORE IMPROVING AHEAD OF THE NEXT UPPER DISTURBANCE. MORE
SHOWERS ARE LIKELY FRIDAY AFTERNOON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......JKL
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
428 AM EDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT SAT MAY 3 2014
WV IMAGERY AND RUC ANALYSIS SHOW AN UPPER TROUGH SITUATED OVER THE
GREAT LAKES REGION...WHILE AN UPPER RIDGE IS LOCATED OVER THE
WESTERN CONUS. THERE ARE A COUPLE EMBEDDED SHORTWAVES WITHIN THIS
UPPER TROUGH THAT WILL BE AFFECTING THE AREA OVER THE NEXT 24
HOURS. THE FIRST WAVE...WHICH IS CURRENTLY MOVING SOUTHEAST OUT OF
WESTERN LAKE SUPERIOR WAS PRODUCING SCATTERED/NUMEROUS SHOWERS OVER
NORTHWEST ONTARIO AND NORTHEAST MINNESOTA THIS PAST EVENING
AND IS NOW PUSHING A NORTH/SOUTH LINE OF SHOWERS ACROSS
WESTERN UPPER MICHIGAN. MODELS HAVE A GOOD AGREEMENT ON THE
EASTWARD MOVEMENT OF THESE SHOWERS AS THE FORCING FROM THE
SHORTWAVE...LEFT FRONT OF THE UPPER JET...MID LEVEL Q-VECTOR
CONVERGENCE...AND THE SURFACE TROUGH STRETCHING SOUTHWEST FROM
THE LOW CENTERED IN SOUTHERN HUDSON BAY MOVE TO THE EAST-SOUTHEAST.
RAINFALL AMOUNTS SHOULDN/T BE MUCH MORE THAN 0.05 TO 0.15 WITHIN
THE HEAVIEST PART OF THESE SHOWERS...WHICH IS SIMILAR TO THE 0.13
INCH RECEIVED AT IRONWOOD AWOS.
BEHIND THE WAVE...SOME MID LEVEL DRYING SEEN UPSTREAM (ASSOCIATED
WITH Q-VECTOR DIVERGENCE) MAY LEAD TO SOME BREAKS IN THE CLOUDS OVER
THE WESTERN CWA (ESPECIALLY NEAR THE WISCONSIN BORDER) AND HAVE
TRENDED TOWARDS A MUCH DRIER FORECAST THAN PREVIOUSLY SHOWN DURING
THE AFTERNOON. THAT IDEA FOLLOWS QPF OUTPUT BY THE MODELS FOR
WESTERN UPPER MICHIGAN...BEFORE THE NEXT WAVE APPROACHES AND BRINGS
INCREASING MID LEVEL MOISTURE FOR TONIGHT. IR SATELLITE AND SURFACE
OBS INDICATE A POCKET OF LOW LEVEL MOISTURE OVER NORTHEAST MINNESOTA
AND NORTHWEST ONTARIO THAT IS PRODUCING CEILINGS AT OR BELOW 1KFT.
THIS COMPLICATES THE SKY COVER FORECAST...AS MODELS INDICATE THIS
LOW CLOUD DECK WILL MOVE INTO THE WESTERN U.P. OVER THE NEXT COUPLE
OF HOURS (STARTING TO SEE HINTS OF IT AT KIWD AT 4AM). WILL
CONTINUE TO HAVE THOSE CLOUDS THROUGH MOST OF THE MORNING BEFORE
THE MODELS SHIFT THE MOISTURE NORTHEAST AND INCREASED MIXING
DEVELOPS. EXPECT THIS NORTHEAST MOVEMENT TO PRODUCE SOME PARTLY
CLOUDY SKIES OVER PORTIONS OF SOUTHWEST UPPER MICHIGAN...ESPECIALLY
ALONG THE WISCONSIN BORDER. THE INCREASE IN MIXING TODAY WILL
PRODUCE SOME GUSTY WEST-NORTHWEST WINDS OVER THE WESTERN 2/3RDS OF
THE CWA BEHIND THE TROUGH. TRENDED WINDS UP IN THOSE AREAS DUE TO
BETTER MIXING SHOWN ON 00Z MODEL RUNS. EXPECT SUSTAINED WINDS IN THE
10-15MPH RANGE WITH GUSTS OF 20-25MPH TO MAYBE EVEN 30MPH OVER THE
KEWEENAW PENINSULA. THESE INCREASED WINDS AND SLIGHTLY DRYER LOW
LEVEL AIR SHOULD HELP TO SCOUR OUT ANY REMAINING FOG OVER THE
EASTERN U.P. THIS MORNING. DID LINGER SOME FOG OVER CENTRAL/EASTERN
PORTIONS OF LAKE SUPERIOR...BUT SHOWED A DIMINISHING TREND WITH THE
DRIER WESTERLY FLOW. FINALLY...HIGHS TODAY LOOK TO BE IN THE UPPER
40S TO LOW/MID 50S...WITH THE HIGHEST VALUES NEAR THE WISCONSIN
BORDER UNDER THE EXPECTATIONS OF SOME SUNSHINE IN THE AFTERNOON.
THE SECOND WAVE...CURRENTLY NORTH OF LAKE WINNIPEG...IS EXPECTED
TO IMPACT THE AREA LATE THIS AFTERNOON AND INTO TONIGHT. WITH THE
TRACK OF THE WAVE AND ITS MERGING WITH ENERGY ROUNDING THE UPPER
RIDGE...THERE IS THE POTENTIAL FOR A FEW SHOWERS ALONG THE
WISCONSIN BORDER LATE THIS AFTERNOON AND THROUGH THE EVENING HOURS.
CONFIDENCE IS LOW ON THE RAIN POTENTIAL...DUE TO MID LEVEL Q-VECTOR
DIVERGENCE...AND WITH LIMITED MODEL QPF AMOUNTS...OPTED TO STICK
WITH SLIGHT AND LOW CHANCE POPS. THE OTHER OPPORTUNITY FOR
PRECIPITATION WILL COME LATE TONIGHT AND INTO SUNDAY MORNING. THE
TROUGH THAT SLIDES THROUGH THE AREA THIS MORNING AND EARLY AFTERNOON
WILL BECOME A CLOSED LOW OVER SOUTHEAST ONTARIO AND SWEEP A
SECONDARY TROUGH ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT. BEST
FORCING/MOISTURE OVER NORTHEAST HALF TO THIRD OF THE CWA...CLOSER TO
THE SECONDARY SURFACE TROUGH...SO WILL KEEP CHANCE POPS OVER
NORTHEAST LAKE SUPERIOR AND LIMIT POPS OVER THE LAND AREAS NEAR
LAKE SUPERIOR TO SLIGHT CHANCES. THE LATEST TRENDS IN THE 00Z
MODELS SEEM TO DELAY THE PRECIP TOWARDS SUNDAY MORNING. IF SHOWERS
HAPPEN...DRY LOWER LEVEL AIR WILL LEAD TO COOLING OF THE COLUMN TO
THE WETBULB TEMP. WITH THE WETBULB0 VALUES AROUND
1600-3000FT THIS EVENING BEFORE FALLING TO THE SURFACE FROM
WEST TO EAST OVERNIGHT...EXPECT THE PRECIP TO BE RAIN
INITIALLY...BEFORE TRANSITIONING TO A RAIN/SNOW MIX AND EVENTUALLY
ALL SNOW (AS COLDER AIR ALOFT SLIDES SOUTHEAST OVER THE AREA). A
TIGHTENING GRADIENT AHEAD OF THE SECONDARY TROUGH WILL KEEP A STEADY
WEST TO EVENTUALLY NORTHWEST WIND GOING THROUGH THE NIGHT...WITH THE
STRONGEST WINDS NEAR LAKE SUPERIOR AND OVER THE KEWEENAW PENINSULA
TOWARDS DAYBREAK (GUSTS TO 20-25MPH). LOWS TONIGHT LOOK TO BE IN
THE LOWER 30S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EDT SAT MAY 3 2014
NAM SHOWS A BROAD 500 MB RIDGE ACROSS THE PLAINS 12Z SUN WITH A
TROUGH IN THE UPPER GREAT LAKES AND ANOTHER IN THE PACIFIC NW. THE
RIDGE AMPLIFIES WITH TIME SUN INTO MON NIGHT ACROSS THE PLAINS AS
THE TROUGH IN THE PACIFIC NW DIGS INTO THE WESTERN U.S.
LOOKS PRETTY QUIET THIS FORECAST PERIOD WITH RAIN AND SNOW SHOWERS
MOVING OUT ON SUNDAY AND WILL GO DRY SUNDAY NIGHT THROUGH MONDAY
NIGHT. DID LOWER TEMPERATURES A BIT FOR SUNDAY NIGHT WITH RIDGING
ACROSS THE AREA AND CLEAR SKIES AND LIGHT WINDS WOULD ALLOW FOR
IDEAL RADIATIONAL COOLING CONDITIONS TO SET UP. MADE A FEW TWEAKS TO
TEMPERATURES ALONG THE LAKESHORES TO ACCOUNT FOR COOLER LAKE BREEZES
COMING IN OFF THE WATER/ICE AREAS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE ACROSS THE
PLAINS WITH A TROUGH IN THE WESTERN U.S. 12Z TUE. THE RIDGE GETS
AMPLIFIED AS IT MOVES INTO THE UPPER GREAT LAKES 12Z WED WHILE THE
TROUGH DIGS INTO THE ROCKIES WITH FURTHER AMPLIFICATION OF THE
PATTERN FOR 12Z THU AS THE TROUGH MOVES SLOWLY EASTWARD. THE TROUGH
MOVES INTO THE UPPER GREAT LAKES 12Z FRI. AS THE RIDGE POKES UP INTO
THE AREA...TEMPERATURES WILL BEGIN A WARMING TREND THIS FORECAST
PERIOD. GFS AND ECMWF SHOW 850 MB TEMPERATURES UP TO 13C ON THU AND
IF WE WOULD MIX THAT DOWN TO THE SFC...WOULD GET UP INTO THE MID
70S. ONLY PROBLEM IS WARM FRONT IS TO THE SOUTH AND THERE WILL BE
PLENTY OF CLOUDS AROUND SO THOSE TEMPERATURES WILL NOT BE REALIZED.
WITH WARM SECTOR STAYING MOSTLY TO THE SOUTH...HAVING THUNDER IN
THERE FOR WED NIGHT THROUGH THU NIGHT STILL LOOKS GOOD. ALSO LOOKS
LIKE THERE COULD BE SOME HEAVY RAIN AS AREA IS NORTH OF THE WARM
FRONT ALLOWING PLENTY OF MOISTURE TO OVERRUN THE WARM FRONT AND GET
WRUNG OUT OVER THE AREA. TEMPERATURES WILL SLOWLY WARM TO NEAR
NORMAL TOWARDS THE END OF THE FORECAST PERIOD. DID GO WITH HIGHER
POPS FOR WED NIGHT THROUGH THU NIGHT WITH WARM FRONT ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 114 AM EDT SAT MAY 3 2014
AS A STRONG DISTURBANCE PASSES OVERNGT...EXPECT SCT-NMRS -SHRA TO
DVLP W-E...BRINGING PREDOMINANT MVFR CONDITIONS INTO SAT MRNG. THE
BEST CHC FOR IFR CONDITIONS WL BE AT IWD AND ESPECIALLY CMX WITH A
WSHFT TO AN UPSLOPE W DIRECTION FOLLOWING PASSAGE OF ACCOMPANYING
SFC LO PRES TROF. GUSTY W WINDS WL DVLP ON SAT UNDER SHARPENING PRES
GRADIENT IN THE WAKE OF THE TROF PASSAGE AND IN PRESENCE OF DAYTIME
HEATING THAT WL ENHANCE MIXING OF STRONGER WINDS TO THE SFC. THE
STRONGEST WINDS ARE MOST LIKELY AT THE MORE EXPOSED CMX LOCATION...
WHERE A LK BREEZE COMPONENT WL ALSO ENHANCE THE FLOW. EXPECT A
RETURN TO VFR CONDITIONS AT ALL 3 SITES BY EARLY AFTN WITH THE
ARRIVAL OF DRIER AIR/DAYTIME MIXING. WINDS WL DIMINISH THIS EVNG
WITH LOSS OF DAYTIME HEATING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT SAT MAY 3 2014
A LOW PRESSURE TROUGH...STRETCHING SOUTHWEST FROM A PARENT LOW OVER
SOUTHERN HUDSON BAY...WILL SHIFT EAST ACROSS LAKE SUPERIOR THIS
MORNING THROUGH THE FIRST HALF OF THE AFTERNOON. AS THIS TROUGH
SHIFTS THROUGH...WINDS WILL VEER TO THE WEST AT 10-25KTS. AS THE
FIRST TROUGH CONTINUES EAST TONIGHT...A SECONDARY TROUGH WILL SLIDE
ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT INTO SUNDAY
MORNING...TURNING WINDS TO THE NORTHWEST AND REMAINING IN THE
10-25KT RANGE. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE SOUTHEAST
OVER THE UPPER GREAT LAKES REGION SUNDAY AFTERNOON AND REMAIN
THROUGH TUESDAY...KEEPING WINDS BELOW 15KTS. A LOW PRESSURE SYSTEM
LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS ON WEDNESDAY WILL LEAD
TO INCREASING SOUTHEASTERLY WINDS...BUT THEY SHOULD REMAIN BELOW
25KTS.
&&
.HYDROLOGY...
ISSUED AT 427 AM EDT SAT MAY 3 2014
STREAMS AND RIVERS WILL CONTINUE TO EXPERIENCE HIGHER LEVELS.
LOCATIONS STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE
STURGEON RIVER OVER HOUGHTON AND BARAGA COUNTIES...THE PAINT RIVER
NEAR CRYSTAL FALLS...THE STURGEON RIVER NEAR NAHMA JUNCTION AND
TAHQUAMENON RIVER NEAR PARADISE.
RIVERS OVER EASTERN UPPER MICHIGAN HAVE STARTED TO STEADY OUT
ON THEIR RISES OVER THE LAST 12 HOURS...SINCE THE HEAVIER
PRECIPITATION SEEN IN THAT AREA WEDNESDAY INTO THURSDAY HAS BEEN
WORKING THROUGH THE BASINS. WITH ONLY LIGHT RAIN EXPECTED TODAY
(GENERALLY UNDER 0.15INCH)...EXPECT THOSE RIVERS LEVELS TO BE STEADY
OR SLOWLY FALL TODAY AND INTO THE FIRST PART OF NEXT WEEK. ONE
INTERESTING ITEM TO NOTE IS THAT THE TAHQUAMENON RIVER NEAR
PARADISE IS CURRENTLY AT 9.57 FEET...WHICH IS THE 3RD HIGHEST LEVEL
ON RECORD /60 YEARS OF DATA/.
WITH A FEW INCHES OF SNOW WATER EQUIVALENT UPSTREAM OF THE STURGEON
RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER...THE
ONGOING SNOW MELT WILL CONTINUE TO FEED WATER INTO THEIR BASINS
EVEN WITH LIGHTER RAINFALL EXPECTED THROUGH SUNDAY MORNING. EXPECT
MULTIPLE DAYS WITH TEMPS IN THE 40S AND 50S THOUGH THE MIDDLE OF
NEXT WEEK TO MELT THE REMAINING SNOW. THE MELT WILL BE SLOWED DOWN
THOUGH AS NIGHTTIME TEMPS WILL STILL BE IN THE LOWER TO MIDDLE 30S.
AFTER THE RAIN THROUGH THE SUNDAY MORNING...THE NEXT CHANCE
OF WIDESPREAD RAINFALL WILL NOT OCCUR UNTIL NEXT WEDNESDAY OR
THURSDAY. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD
CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KC
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
333 AM EDT SAT MAY 3 2014
.SYNOPSIS...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WEAK LOW PRESSURE WILL CROSS LOWER MICHIGAN TODAY...AND SLOWLY MOVE
OFF TO THE EAST. OUR LONG PERIOD OF WET WEATHER WILL FINALLY END BY
SUNDAY AFTERNOON...AS HIGH PRESSURE BUILDS SOUTHEAST FROM CENTRAL
CANADA. COOL WEATHER WILL CONTINUE INTO EARLY IN THE WORK WEEK...BUT
THINGS WILL TURN WARMER BY THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT SAT MAY 3 2014
CURRENTLY, SFC TROUGH/WEAK COLD FRONT IS BEGINNING TO MOVE ACROSS
NORTHERN LAKE MICHIGAN WITH A 500 MB SHORTWAVE TROUGH/SPEED MAX
DIVING INTO THE MAIN 500 MB TROUGH CURRENTLY OVER THE UPPER GREAT
LAKES. THERE ARE SOME SHOWERS ASSOCIATED WITH THIS WAVE. TO THE
WEST, THERE IS A DECENT AREA OF SUBSIDENCE AND DRYING IN THE UPPER
MISSISSIPPI VALLEY. THE RAIN SHOWERS AND THE DRYING WILL BE THE MAIN
CONCERNS WITH THIS PACKAGE.
TODAY...WHILE THE GFS AND ECMWF MODELS HAVE SIMILAR CONFIGURATION
WITH THE QPF, THE GFS IS MORE INTENSE, SO THINKING THAT THERE HAS
BEEN A LITTLE GRID SCALE FEEDBACK. HOWEVER, WITH THAT SAID THE MASS
FIELDS ARE COMPARABLE BETWEEN THE TWO. THE NAM LOOKS SIMILAR TO THE
GFS WITH THE SFC LOW MOVING INTO WC LOWER, AND SPREADING RAIN
FARTHER NORTH INTO THE FORECAST AREA. THE RUC13 SEEMS TO BE HANDLING
THE PRECIPITATION LIKE THE ECMWF, WHICH SEEMS TO BE FOLLOWING THE
CURRENT TRENDS OF THE RADAR ATTM. IT LOOKS LIKE THERE WILL BE A
NUMEROUS RAIN SHOWERS ALONG AND SOUTH OF M-72 AS SFC TROUGH MOVES TO
THE EAST BETWEEN US-10 AND I-96 DOWNSTATE. THERE IS A SECOND AREA OF
LIGHT RAIN BETWEEN AND KRRL AND W LAKE SUPERIOR. WHICH WILL SWEEP
THROUGH UPPER MICHIGAN AND AREAS NORTH OF M-32 THIS MORNING. BY 18Z,
THE RAIN WILL LIKELY BE ON THE EAST SIDE OF THE STATE AS THE DRY AIR
NOTED IN THE MISSISSIPPI VALLEY NOW, SHOULD BE PUSHING INTO NW LOWER
AND C UPPER.
TONIGHT...AS THE DRY AIR PUSHES THROUGH THE REGION, THERE WILL STILL
BE SOME MOISTURE IN THE LOWER LEVELS (850 MB AND LOWER RH IS AROUND
70%) AND WITH ANOTHER 500 MB SHORTWAVE TROUGH ROTATING THROUGH LAKE
SUPERIOR, THAT WE GE THE CHANCE FOR RAIN SHOWERS, MIXED WITH SOME
SNOW IN E UPPER, AS THE 850 MB TEMPERATURES FALL TO AROUND -4C WITH
THE SFC TEMPERATURES FALLING TO THE MID 30S. THERE COULD ALSO BE
SOME SNOW MIXING IN WITH THE RAIN IN THE N LOWER HIGHLANDS, AROUND
GAYLORD AS TEMPERATURES FALL TO THE MID 30S THERE AS WELL.
&&
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 331 AM EDT SAT MAY 3 2014
THERE APPEAR TO BE ACTUAL CHANGES ON THE HORIZON. UPPER FLOW FINALLY
GETS UNSTUCK AND BECOMES MORE PROGRESSIVE. AFTER ONE FINAL SHORTWAVE
SQUEEZES BY SUPERIOR/EASTERN UPPER MI EARLY SUNDAY...RIDGING OUT
WEST WILL SLOWLY BUILD EAST INTO THE PLAINS AND UPPER MS VALLEY. AT
THE SURFACE...WEAK HIGH PRESSURE NOSES IN FROM THE NW...AND HANGS
OUT THRU MONDAY. THE AIRMASS IS INITIALLY STILL QUITE COOL...AND
SUBSTANTIAL WARM ADVECTION WILL NOT BE SEEN AT LOW LEVELS UNTIL
LATER IN THE WEEK. BUT OUR AIRMASS WILL MODERATE IN PLACE AS EARLY
MAY SUNSHINE FINALLY GETS A CHANCE TO DO SOMETHING. SO SUNNIER AND
MILDER WX IS IN STORE EVENTUALLY...THOUGH THE NIGHTS WILL STILL BE
SEASONABLY COOL.
SUNDAY...ANOTHER SHOT OF COLD ADVECTION WILL BE UNDERWAY AT THE
START OF THE DAY...BEHIND A COLD FRONT ADVANCING INTO SOUTHERN LOWER
MI. A FAIRLY POTENT 500MB VORT RIBBON WILL EXTEND FROM ISLE ROYALE
TO CENTRAL LAKE HURON IN THE MORNING. IT/S PROGRESS EASTWARD WILL
SET US UP FOR SUBSTANTIAL NVA AND DEEP DESCENT BY MID/LATE
AFTERNOON. BUT UNTIL THEN...WE/LL BE FIGHTING OFF A SHOWER THREAT
FOR A FEW MORE HOURS. BEST CHANCE FOR PRECIP SHOULD BE BENEATH AND
NORTH OF THE VORT RIBBON. SOME DPVA DYNAMICS WILL BE FOUND BENEATH
THE RIBBON. TO THE NORTH...WE WILL SEE THE COLDEST TEMPS ALOFT (-32C
AT 500MB OVER EASTERN UPPER AT 12Z) AND CORRESPONDING STEEP LAPSE
RATES (700-500MB LAPSE RATES 7.5-7.75C/KM). SOME POTENTIAL FOR MIXED
PRECIP OVER EASTERN UPPER AND ESPECIALLY THE HIGH TERRAIN OF
NORTHERN LOWER MI...WHERE THE MELTING LAYER LOWERS TO AROUND 1K FT
THICK. WILL CUT OFF PRECIP AT 16Z...THOUGH COLD-AIR CUMULUS WILL
MAINTAIN PARTLY TO MOSTLY CLOUDY SKIES. THE CHILLY AIRMASS (850MB
TEMPS -3 TO -4C) AND LIMITED SUNSHINE WILL KEEP MAX TEMPS IN THE
UPPER 40S TO LOWER 50S...PERHAPS A BIT WARMER IN THE FAR SE.
SUN NIGHT/MONDAY...WITH LOSS OF HEATING...CU FIELD SHOULD DIMINISH
WITH TIME SUNDAY EVENING IN NORTHERN LOWER. SOME SIGNS OF MSLP
TROFFING AND ASSOCIATED 1000-850MB CONVERGENCE HANGING AROUND
EASTERN UPPER FOR MUCH OF THE NIGHT. THAT WOULD HELP SOME RESIDUAL
STRATOCU LINGER FOR MUCH OF THE NIGHT OVER FAR NORTHERN LOWER AND
POINTS NORTH. THE ARRIVAL OF BUBBLE HIGH PRESSURE SHOULD DIMINISH
THE LOW CLOUD PRESENCE ON MONDAY. HOWEVER...THE LEFTOVER FRONT FROM
THE OHIO VALLEY INTO THE DAKOTAS WILL BECOME MORE ACTIVE...WITH SOME
ASSOCIATED HIGH CLOUD DEBRIS ENTERING THE REGION FROM THE WEST.
STILL...THINGS LOOKS PARTLY SUNNY AT WORST.
MIN TEMPS IN THE UPPER 20S TO LOWER 30S...THOUGH SOME OF THE USUAL
COLD SPOTS WILL DIP A LITTLE LOWER. MAX TEMPS 50 TO 60F.
REST OF THE FORECAST...UPSTREAM 500MB RIDGE AXIS WILL AMPLIFY A BIT
BY THE TIME IT MOVES OVERHEAD EARLY THURSDAY. AN UPPER LOW STALLED
OVER THE CANADIAN PRAIRIE WILL EVENTUALLY HELP PUSH THE RIDGE EAST
AND/OR SUPPRESS IT TOWARD NEXT...THOUGH THE MANNER IN WHICH THIS
HAPPENS IS STILL UNCERTAIN. REGARDLESS...THIS IS A MUCH WARMER
PATTERN...AND TEMPS WILL CLIMB AS WE PROGRESS THRU THE WORK WEEK.
HOWEVER...THE EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING MCS/S
INTO THE RIDGE AXIS BEGINNING AS SOON AS WED NIGHT. THIS HAS CLEAR
POTENTIAL TO MESS UP OTHERWISE WARM WX...AND WILL NOT GO WILD WITH
MAX TEMPS LATE IN THE WEEK AT THIS TIME.
AS FOR PRECIP...INITIAL SURGE OF WARM ADVECTION COULD PRODUCE SOME
SHRA ON WED (THOUGH WILL LEAVE OUT THUNDER). THINGS GRADUALLY GET
STORMIER INTO THURSDAY/THU NIGHT. FRIDAY LOOKS HIGHLY UNCERTAIN AS
THIS TIME...DEPENDING ON TIMING WE MAY TRY TO DRY OUT BEHIND A WEAK
COLD FRONT (ECMWF) OR NOT SEE FROPA UNTIL FRIDAY NIGHT (GFS). SO
CHANCY POPS STILL IN ORDER THAT FAR OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 127 AM EDT SAT MAY 3 2014
SUMMARY: AN UPPER LEVEL DISTURBANCE WILL BRING A RENEWED ROUND OF
SHOWERS TO NORTHERN MICHIGAN FOR SATURDAY MORNING...BEFORE GRADUALLY
IMPROVING CONDITIONS AS HIGH PRESSURE GRADUALLY BUILDS TOWARDS THE
GREAT LAKES.
RESTRICTIONS: CONDITIONS DETERIORATING AS OF THIS WRITING WITH A
PERIOD OF IFR CIGS LIKELY THROUGH EARLY MORNING ALL TERMINALS. ALSO
EXPECT SOME LIGHT FOG...BUT EXPECT CIGS WILL BE THE MORE RESTRICTIVE
ELEMENT. A NEW ROUND OF SHOWERS ARRIVES FOR THE FIRST HALF OF
SATURDAY...WITH ONLY GRADUAL IMPROVEMENT EXPECTED UNTIL AFTERNOON.
EXPECT A TRANSITION TO MVFR CONDITIONS DURING THE MORNING...WITH VFR
LIKELY TOWARDS EVENING AND CONTINUING THROUGH THE END OF THE TAF
PERIOD.
WINDS: CALM/LIGHT-VARIABLE WINDS WILL CONTINUE INTO SATURDAY
MORNING BEFORE GIVING WAY TO STRENGTHENING NORTHWEST WINDS
/12G20KTS/ DURING THE AFTERNOON. NORTHWEST WINDS WILL SUBSIDE TO
5-10KTS SATURDAY EVENING.
LLWS: NO THREAT THIS CYCLE.
THUNDER: LOW END THUNDER THREAT CONTINUES FOR THE LATE MORNING/EARLY
AFTERNOON ON SATURDAY BEFORE SHOWER ACTIVITY DEPARTS EAST OF THE
REGION. THREAT REMAINS TOO LOW TO WARRANT MENTION IN THE TAFS...BUT
IF IT DOES OCCUR...THERE IS A CHANCE OF SMALL HAIL/GRAUPEL GIVEN LOW
FREEZING LEVELS.
&&
.MARINE...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WINDS TODAY WILL BEGIN TO VEER IN THE AFTERNOON AS THE FRONT MOVES
THROUGH THE REGION, AND ONCE WINDS ARE OUT OF THE NW THEY SHOULD
INCREASE A BIT TONIGHT. HOWEVER, THE PRESSURE GRADIENT BEGINS TO
TIGHTEN AND THE FAVORED COASTAL CONVERGENCE AREA, FROM THE MACKINAC
BRIDGE TO PRESQUE ISLE LIGHT WILL PROBABLY SEE SMALL CRAFT GUSTS AND
POSSIBLY WAVES EARLY ON SUNDAY, THEN AS THE HIGH BUILDS INTO THE
UPPER GREAT LAKES IN THE AFTERNOON AND NIGHT, THE WINDS WILL
DIMINISH.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...JZ
SHORT TERM...JL
LONG TERM...JZ
AVIATION...ARNOTT/JSL
MARINE...JL
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
411 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SAT MAY 3 2014
WATER VAPOR IMAGERY OVERLAYED WITH A RAP H5 ANALYSIS SHOWS A
RATHER EXPANSIVE UPPER LOW SPINNING TO THE SW OF HUDSON BAY WITH
AN UPPER RIDGE OVER THE ROCKIES BEGINNING TO GET FLATTENED OUT BY
AN UPPER LOW APPROACHING THE WASHINGTON/BC COAST. OUR LOCATION
BETWEEN THE HUDSON UPPER LOW AND WESTERN RIDGE HAS PLACED STRONG
NORTHWEST MID AND UPPER LEVEL JETTING ACROSS THE UPPER MIDWEST.
THIS JETTING IS IN PLACE IN RESPONSE TO A STRONG MID LEVEL THERMAL
GRADIENT THAT IS IN PLACE BETWEEN THESE TWO FEATURES AS WELL. THIS
TYPE OF WEATHER PATTERN WILL SUPPLY US WITH PLENTY OF MID AND
UPPER LEVEL CLOUD COVER THROUGH THE DAY TODAY...THAT WILL START TO
CLEAR OUT FOR ALL BUT THE SOUTHWEST TONIGHT.
BIGGEST ISSUE FOR PRECIP THIS PERIOD WILL BE LACK OF LOW LEVEL
MOISTURE...HOWEVER THERE STILL LOOKS TO BE A COUPLE OF SHOTS FOR
PRECIP. THIS FIRST WILL COME THIS AFTERNOON AND IS ASSOCIATED WITH
CLOUD COVER AND SPRINKLES OVER NW MN. THE MPX AND SPC WRFS ALONG
WITH MEMBERS 1 AND 3 OF THE HOPWRF ALL SHOW THE ADDITION OF DAYTIME
HEATING LEADING TO THE DEVELOPMENT OF ISO-SCT SHOWERS ALONG AND
EAST OF THE MISSISSIPPI RIVER...SO PULLED THE EXISTING 20 POP WE
HAD SOUTHWEST TO JUST WEST/SOUTH OF THE MS RIVER. LOOKING AT MIXED
LAYER DEWPOINTS FROM THE GFS/NAM...A RIBBON OF HIGHER MOISTURE
LOOKS TO HANG BACK ALONG THIS AXIS...ALLOWING FOR THE DEVELOPMENT
OF DIURNAL SHOWERS.
THE SECOND AND BETTER CHANCE OF PRECIP ARRIVES LATE TONIGHT AS A
ZONE OF STRONG FGEN IN THE H7-H6 LAYER ALONG WITH ISENTROPIC
UPGLIDE ON THE 305K SFC SENDS A BAND OF PRECIP FROM THE CENTRAL
ND/SD BORDER SOUTHEAST INTO NORTH CENTRAL IOWA. BY THE END OF THE
SHORT TERM...WE HAVE LIKELY POPS SHOWING UP SOUTH OF THE MN RIVER
IN ASSOCIATION WITH THIS FORCING. THE ONLY MODEL THAT DOES NOT
REALLY AGREE WITH THIS SCENARIO IS THE GFS. ALTHOUGH IT HAS THE
FGEN/ISENTROPIC FORCING...IT DOES NOT PRODUCE ANY QPF. QUICK LOOK
AT SOME RH TIME-HEIGHT CROSS SECTIONS SHOWS THE PROBLEM...THE GFS
NEVER SATURATES THE ATMO BELOW H8. GIVEN THE STRENGTH OF THE
FORCING...TEND TO BELIEVE PRECIP GENERATED WILL BE STRONG ENOUGH
TO OVERCOME THE DRY AIR SO FAVORED A NON-GFS FORECAST FOR THIS
PRECIP LATE TONIGHT.
TEMPERATURES TODAY WILL BE SIMILAR TO WHAT WAS SEEN FRIDAY AS WE
LOOK TO MIX UP TO AROUND 775 MB. ALSO SIMILAR TO YESTERDAY WILL BE
THE BREEZY CONDITIONS...THOUGH NORTHWEST WINDS WILL NOT BE QUITE
AS STRONG AS WHAT WE SAW FRIDAY OUT IN WESTERN MN. TONIGHT...
EXTENT OF CLOUD COVER WILL PLAY A LARGE ROLL IN WHERE TEMPERATURES
END UP SETTLING TO. IN THE SOUTHWEST...MAINLY CLOUDY SKIES WILL
HOLD TEMPS UP AROUND 40...BUT MOSTLY CLEAR SKIES IN THE NORTHEAST
CWA WILL ALLOW TEMPERATURES TO FALL BACK TO AROUND 30 WITH THE
PROBABILITY OF A FREEZE STEADILY INCREASING THE FARTHER NORTHEAST
YOU GET FROM I-94. AT THIS POINT...WE ARE STILL EARLY ENOUGH IN
THE GROWING SEASON NORTH OF I-94 THAT NO FROST/FREEZE PRODUCTS ARE
NECESSARY YET.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 345 AM CDT SAT MAY 3 2014
SUNDAY THROUGH TUESDAY...A FAIRLY BENIGN PATTERN WILL PERSIST FOR
THE EARLY PORTION OF THE UPCOMING WEEK DUE TO GENERALLY UPR LVL
RIDGING OVER THE CENTRAL CONUS WITH WEAK SFC PRES PATTERNS ACRS
THE REGION. SEVERAL WEAK UPR LVL DISTURBANCES WILL RIDE THE
PERIPHERY OF THE RIDGE THRU THE REGION...MAINLY LATE SUN MRNG AND
LATE SUN NIGHT...AND AFFECTING MAINLY W AND S MN WITH OCNL SHWRS
AND POSSIBLY AN ISOLD TSTM. NOT LOOKING FOR MUCH IN THE WAY OF QPF
SINCE DEEP MOISTURE IS FAIRLY CONFINED AND UPR LVL SUPPORT IS WEAK
AT BEST. DID SHOW POPS INTO THE UPR CHC AND LOW-END LIKELY RANGE
SUN MRNG DUE TO MODEL CONSISTENCY...BUT CONFIDENCE DROPS FOR SUN
NIGHT SO ONLY USED LOW-MID CHC RANGE. TEMPS WILL START A GRADUAL
WARMING TREND DURG THIS PERIOD...ESP BY TUE AS THE RIDGE IS FAIRLY
ESTABLISHED AND SLY WINDS BECOME MORE PROMINENT.
WEDNESDAY THROUGH FRIDAY...A MORE ACTIVE PATTERN IS EXPECTED AS A
LARGE UPR LVL TROF MOVING ONSHORE THE CALI COAST...SHIFTING SWD
FROM THE GULF OF ALASKA...INTERACTS WITH A DEVELOPING LOW PRES
CENTER OVER THE CO/KS REGION DURG THE DAY ON WED. AS THE LARGE
TROF DRAGS MOISTURE WITH IT FROM THE PACIFIC INTO THE CENTRAL
CONUS...AND HELPS INTENSIFY THE LOW PRES CENTER...THESE FEATURES
WILL ALL STREAM INTO THE MID-TO-UPR MISSISSIPPI RIVER VALLEY WED
INTO THU...PRODUCING PERIODS OF SCATTERED SHWRS/TSTMS FOR THE AREA
TUE NIGHT THRU THU NIGHT. THERE IS STILL MUCH UNCERTAINTY WITH
RESPECT TO THE TRACK OF THE SYSTEM AND HOW MUCH DRY AIR BECOMES
ENTRAINED INTO THE SYSTEM. THIS WILL AFFECT NOT ONLY QPF AMOUNTS
BUT ALSO THE POTENTIAL FOR ANY SEVERE WX SINCE INSTABILITY WILL BE
HIGHLY DEPENDENT ON HOW MUCH WARM-SECTORING CAN OCCUR AND IF
HIGHER LOW-LEVEL MOISTURE /DEWPOINTS/ ARE ADVECTED NWD ALONG WITH
WARMER AIR. HAVE MAINTAINED TSTM MENTION FOR THE ENTIRE CWFA.
TEMPS DO CONTINUE THEIR WARMING TREND MID-TO-LATE WEEK WITH THE
ENTIRE CWFA HAVING HIGHS CLIMB TO THE MID 60S...AND POSSIBLY INTO
THE LOWER 70S NEAR I-90.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1054 PM CDT FRI MAY 2 2014
WINDS HAVE DIMINISHED SIGNIFICANTLY LATE THIS EVENING ACROSS
EASTERN MN AND WESTERN WI IN THE WAKE OF THE LOW PRESSURE SYSTEM
THAT MOVED THROUGH LATE IN THE AFTERNOON. DEW POINTS HAVE NOT
FALLEN MUCH THIS EVENING FROM KMSP ON EAST. THIS LEADS TO A FOG
CONCERN OVERNIGHT ALONG AND EAST OF THE I-35 CORRIDOR. HAVE
INCLUDED MVFR VSBYS IN BR FOR KRNH AND KEAU OVERNIGHT. ON THE FLIP
SIDE...CLOUDINESS IS STILL EXPECTED TO THICKEN FROM THE NORTHWEST
OVERNIGHT AND THIS SHOULD HELP KEEP THE FOG FROM BECOMING
WIDESPREAD AND DENSE. OTHERWISE...STILL LOOKING AT MAINLY VFR
CONDITIONS THROUGH THE PERIOD. NW WINDS 18G25KTS EXPECTED AT MOST
OF THE MN TAF SITES BY SATURDAY AFTERNOON.
KMSP...THERE IS A SMALL THREAT FOR MVFR BR DEVELOPING AT THE
AIRFIELD OVERNIGHT. HOWEVER...MID LEVEL CLOUDINESS IS ALSO
FORECAST TO SPREAD IN FROM THE NORTHWEST OVERNIGHT...AND THIS
SHOULD HELP MITIGATE THE BR PROBLEM. STILL THINKING VFR THROUGH THE
PERIOD. NW WINDS 18G25KTS REMAIN IN THE FORECAST FOR SATURDAY
AFTERNOON.
/OUTLOOK FOR KMSP/
SUN...VFR. NW WINDS 5 KTS BECOMING NE.
MON...VFR. SLIGHT CHANCE -SHRA. E WINDS 5-10 KTS.
TUE...VFR. SLIGHT CHANCE -SHRA. ESE WINDS 8-12 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JPC
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
316 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT SAT MAY 3 2014
A FEW SPRINKLES ARE ONGOING THIS MORNING AND THE RAP MODEL
INDICATES SOME VERY WEAK MIDLEVEL FRONTOGENESIS AT THE 700-500MB
LEVEL. THIS RAIN IS INDICATIVE OF MOISTURE POOLING IN THE
NORTHWEST FLOW ALOFT AND...FOR NOW...WILL BE DISCOUNTED AS
INSIGNIFICANT.
THE RAP AND OTHER MODELS SHOW K INDICES INCREASING TO 30 TO 35C
LATE THIS AFTERNOON AND THIS EVENING ACROSS WRN NEB. THE RAP EVEN
SHOWS SOME LIFT IN THIS MOISTURE POOL AT 00Z THIS EVENING. SO
FOLLOWING THE 00Z NAM...ISOLATED SHOWERS AND THUNDERSTORMS ARE IN
THE FORECAST THIS EVENING ACROSS THE PANHANDLE AND THE WRN
SANDHILLS. ANYTHING THAT FORMS SHOULD MOVE EAST AND DECAY AROUND
03Z-06Z.
THE MODEL CONSENSUS ALSO SHOWS ISOLATED SHOWERS AND THUNDERSTORMS
WORKING INTO THE NERN ZONES TONIGHT. THE NAM SHOWS STRONG
MIDLEVEL FRONTOGENESIS ALONG AND JUST NORTH OF THE MISSOURI RIVER
SUPPORTING THIS RAIN.
HIGHS TODAY...FROM NEAR 70 IN THE NORTHEAST TO LOWER 80S
SOUTHWEST IS BASED ON A MULTI-MODEL APPROACH. THE MODELS ARE
TIGHTLY CLUSTERED AROUND 80F AT NORTH PLATTE THIS AFTERNOON. LOWS
TONIGHT FALL INTO THE 40S. A STATIONARY FRONT WILL SETTLE INTO
THE NORTH PLATTE VALLEY AND THIS SHOULD KEEP THE ATMOSPHERE WELL
MIXED WITH LOWS IN THE UPPER 40S ACROSS SRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT MAY 3 2014
LOW AMPLIFIED UPPER LEVEL RIDGE ACROSS THE SOUTHERN PLAINS WITH
NEARLY ZONAL FLOW FOR THE HIGH PLAINS ON SUNDAY. LEE SIDE TROUGH
ALONG THE FRONT RANGE WITH A COLD FRONT STALLING FROM THE HILLS
INTO N CENTRAL KS. DECENT TEMPERATURE SPREAD ACROSS THE CWA WITH
MID 60S ACROSS MUCH OF N CENTRAL NEB...WHILE FAR SW NEB WARMS
INTO THE UPPER 80S. MODELS ARE WAVERING SLIGHTLY WITH THE SW PUSH
OF THE COLD AIR...WITH SOME UNCERTAINTY TO TEMPS ACROSS THE CWA.
A LIGHT MOVEMENT EITHER WAY COULD CAUSE A 10 PLUS DIFFERENCE IN
TEMPS. ONE THING WITH HIGHER CONFIDENCE IS THE DRY AIR IN PLACE
AND PARTLY TO MOSTLY SUNNY SKIES.
BY MONDAY PACIFIC LOW WILL PUSH ONSHORE...INTO THE PACIFIC NW.
THE QUASI-STATIONARY SFC FRONT WILL STILL BE ACROSS THE AREA.
SUNNY TO MOSTLY SUNNY SKIES WILL HELP TO WARM N CENTRAL TO OR A
FEW DEGREES WARMER THAN SUNDAY. THE RIDGE AXIS IS SLIGHTLY
FURTHER EAST SO DID NOT TAKE HIGHS QUITE AS WARM IN THE SW. BY
MONDAY EVENING A WEAK DISTURBANCE WILL DRIFT EAST ACROSS S DAKOTA
AND MAY TAP PORTIONS OF NORTHERN NEB. FOR NOW HAVE LOW POPS IN
THE HIGHER TERRAIN WHERE CLOUD BASES A LITTLE LOWER AND A BETTER
CHANCE FOR ANY DEVELOPMENT TO MAKE IT THROUGH THE DRY BL.
TUESDAY WILL BE THE START OF A MORE ACTIVE PERIOD. THE PACIFIC NW
TROUGH WILL SLOWLY DIG TOWARDS THE 4 CORNERS BY THURSDAY. A
COUPLE OF MID LEVEL SHORT WAVES EJECT OVER THE AREA AHEAD OF THE
MAIN LOW. EACH WAVE WILL BRING THE CHANCE FOR STORMS. STRONG CAP
WITH LIMITED MOISTURE SO SOME CONCERNS TO HOW WIDESPREAD ANY
ACTIVITY WILL BE AND KEPT POPS AT OR LESS THAN 50 PERCENT.
MEANWHILE THE RIDGE AXIS SHIFTS EAST WITH TEMPS COOLING FROM THE
NW.
THEN FOR WED AND THURS...WITH A BETTER CHANCE FOR PRECIP EXPECTED
AND AT LEAST MORE CLOUDINESS...HAVE HIGHS IN THE UPPER 50 TO
LOWER 70S...WARMEST IN THE SOUTH. MOISTURE IS STILL A CONCERN AS
BEST MOISTURE GETS TURNED TO THE NE BEFORE MAKING IT TO THE CWA.
MODELS ARE IN BETTER AGREEMENT WITH TROUGH AXIS TO QUICKLY EJECT
ACROSS THE PLAINS ON FRIDAY AND FRIDAY NIGHT. DRY SLOT MAY PLAY
INTO THE AREA PENDING THE EXACT TRACK OF THE LOW...WHICH IS STILL
UP IN THE AIR. CURRENT THOUGH IS MORE DRY SLOT THAN NOT AND
SHOULD SEE HIGHS BACK INTO THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1223 AM CDT SAT MAY 3 2014
UNLIMITED CEILING AND VISIBILITY CAN BE EXPECTED IN CENTRAL AND
WESTERN NEBRASKA TONIGHT THROUGH SATURDAY. SOME RESIDUAL
CLOUDINESS IN THE WAKE OF THE SHOWERS AND THUNDERSTORMS IN
SOUTHWEST NEBRASKA WILL PERSIST UNTIL ABOUT 08Z.
WIND IS EXPECTED TO SWING AROUND TO THE SOUTHEAST SATURDAY
AFTERNOON AND EVENING...INCREASING TO 10-14KT LATE SATURDAY
AFTERNOON AND EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1219 AM CDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 1219 AM CDT SAT MAY 3 2014
LATEST LOCAL AND REGIONAL RADAR SHOWS AN AREA OF LIGHT RAIN FROM
KJMS SOUTHWEST TO NAPOLEON...WHICH IS OCCURRING ALONG A SECONDARY
COLD FRONT. DURATION OF PRECIPITATION HAS BEEN AVERAGING AROUND 10
MINUTES WITH TRACE AMOUNTS REPORTED. THIS WILL QUICKLY SCOOT AWAY
FROM THE JAMES RIVER VALLEY AS THE FRONT CONTINUES TO PRESS
SOUTHEAST. MEANWHILE...VERTICAL MOTION ASSOCIATED WITH AN
ADVANCING SHORTWAVE AND THE RIGHT ENTRANCE REGION OF A 300MB 120KT
JET IN NORTHEAST MONTANA...HAS DEVELOPED AN AREA OF RAIN SHOWERS
FROM GLASGOW NORTHWEST INTO SOUTHERN CANADA. THE RAP13 TRACKS THIS
LIGHT PRECIPITATION FIELD INTO THE WEST AND SOUTHWEST BEGINNING IN
THE NEXT FEW HOURS AND IS EXPECTED TO CONTINUE INTO THE MID/LATE
MORNING HOURS SATURDAY. ADJUSTED POPS HIGHER AND EXPANDED THEM
FARTHER NORTH AND EAST BASED ON THE RAP SOLUTION AS COMPARED TO
REGIONAL RADAR/SURFACE OBSERVATIONS UPSTREAM. REST OF FORECAST
REMAINS IN GOOD SHAPE.
UPDATE ISSUED AT 928 PM CDT FRI MAY 2 2014
REGIONAL RADARS CONTINUE TO DETECT AN AREA OF SHOWERS EXTENDING
FROM DEVILS LAKE TO HARVEY...WEST INTO GARRISON AND BEULAH MOVING
SOUTHEAST AROUND 40 MPH. HOWEVER...NONE OF THE SURFACE OBS HAVE
INDICATED LIGHT RAIN SHOWER ACTIVITY REACHING THE SURFACE. STILL
THINK MOST OF THIS IS FALLING AS VIRGA. HOWEVER...A FEW RAINDROPS
STILL COULD REACH THE SURFACE OVERNIGHT. THEREFORE...WILL CONTINUE
TO CARRY SLIGHT TO LOW-END CHANCE POPS OVER WESTERN AND CENTRAL
NORTH DAKOTA TONIGHT.
THE REMAINING FORECAST ELEMENTS ARE IN GOOD SHAPE WITH NO MAJOR
UPDATES REQUIRED. THE FRESHENED UP PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 706 PM CDT FRI MAY 2 2014
ELEVATED ISOLATED TO SCATTERED RAIN SHOWERS WILL CONTINUE TO TRACK
SOUTHEAST ACROSS NORTH DAKOTA THIS EVENING. THIS ACTIVITY IS
ASSOCIATED WITH A 125-KNOT JET STREAK NOSING INTO NORTH DAKOTA.
PRELIMINARY 00Z KBIS SOUNDING DATA INDICATES VERY DRY BOUNDARY
LAYER CONDITIONS...WITH MOST OF THESE RAIN SHOWERS FALLING AS
VIRGA. HOWEVER...STILL CANNOT RULE OUT THE POSSIBILITY OF SOME
RAIN DROPS REACHING THE SURFACE. AS A RESULT...MAINTAINED THE
SLIGHT CHANCE/LOW-END CHANCE POPS OVER WESTERN AND CENTRAL NORTH
DAKOTA TONIGHT. THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE.
THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 404 PM CDT FRI MAY 2 2014
CURRENTLY...SCATTERED SHOWERS CONTINUE TO TRACK SOUTHEAST ACROSS
EASTERN MONTANA AND INTO SOUTHWEST NORTH DAKOTA ASSOCIATED WITH A
BAROCLINIC ZONE DRAPED ACROSS MONTANA AND THE WESTERN DAKOTAS.
ANOTHER AREA OF SHOWERS WAS LOCATED OVER SOUTHEAST SASKATCHEWAN
AND SOUTHWEST MANITOBA. THIS IS ASSOCIATED WITH A SHORTWAVE
CURRENTLY OVER SOUTHERN MANITOBA.
FOR TONIGHT...EXPECT A CONTINUATION OF ISOLATED TO SCATTERED
SHOWERS ALONG THE BAROCLINIC ZONE TONIGHT INTO SATURDAY MORNING AS
THERE IS LITTLE OVERALL MOVEMENT OF THE ZONE THROUGH SATURDAY.
PRECIPITATION AMOUNTS WILL BE LIGHT THOUGH WITH MOST AREAS
RECEIVING ONLY VIRGA OR TRACE AMOUNTS. A FEW LOCALS COULD SEE A
COUPLE HUNDREDTHS. THE SHORTWAVE TRACKING SOUTHEAST THROUGH
MANITOBA WILL BRING A CHANCE OF LIGHT PRECIPITATION TO CENTRAL
NORTH DAKOTA THIS EVENING. PRECIPITATION AMOUNTS ARE EXPECTED TO
BE LIGHT WITH THIS FEATURE AS WELL.
ON SATURDAY...A REINFORCING SHOT OF COOL AIR BEHIND THE
AFOREMENTIONED SHORTWAVE WILL BRING COOLER TEMPERATURES TO MOST
AREAS ON SATURDAY. HIGHS ARE EXPECTED TO STRUGGLE TO REACH THE 50S
NORTHEAST WITH MID TO UPPER 50S POSSIBLE SOUTH CENTRAL. SKY COVER
WILL REMAIN HIGHEST ACROSS THE SOUTHWEST...WITH SCATTERED TO
ISOLATED SHOWERS REMAINING...WITH LESS CLOUD COVER NORTH AND EAST
CLOSER TO THE SURFACE HIGH.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 404 PM CDT FRI MAY 2 2014
FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE INCREASING POTENTIAL
FOR SOME BRIEF PERIODS OF LIGHT SNOW LATE SATURDAY NIGHT INTO EARLY
SUNDAY ACROSS THE SOUTHWEST HALF OF THE STATE...AND ACTIVE WEATHER
NEXT WEEK.
SATURDAY NIGHT AND SUNDAY...UPPER LEVEL ENERGY IMPULSES ARE FORECAST
TO MOVE THROUGH ZONAL FLOW ALOFT. AT THE SURFACE A BAROCLINIC ZONE
SETS UP WITH GENERAL LOW PRESSURE OVER COLORADO AND HIGH PRESSURE
FROM CENTRAL CANADA TO THE WESTERN GREAT LAKES. EXPECT SHOWERS
SATURDAY NIGHT IN THE SOUTHWEST...EXPANDING INTO THE WESTERN HALF OF
THE STATE SUNDAY. THERE MAY BE SOME THUNDER IN THE FAR SOUTHWEST ON
SUNDAY AFTERNOON.
SUNDAY NIGHT THROUGH FRIDAY...AN UPPER LEVEL LONGWAVE TROUGH
DEVELOPS OVER THE ROCKIES AND DEEPENS/EXPANDS THROUGHOUT NEXT WEEK.
AT THE SURFACE...THIS WILL RESULT IN NEAR PERSISTENT LOW PRESSURE IN
THE LEE OF THE ROCKIES - MAINLY IN THE COLORADO AREA. A SERIES OF
UPPER LEVEL SHORTWAVE ENERGY IMPULSES MOVING FROM THE BASE OF THE
TROUGH (4-CORNERS AREA) TOWARDS THE NORTHERN PLAINS...COMBINED WITH
SOUTHEASTERLY LOW LEVEL FLOW ASSOCIATED WITH SURFACE LOW PRESSURE IN
THE LEE OF THE ROCKIES...WILL RESULT IN A PROLONGED PERIOD OF
UNSETTLED WEATHER FOR A LARGE PORTION OF THE CENTRAL US. FOR NORTH
DAKOTA...THIS WILL MEAN CHANCES OF SHOWERS SUNDAY NIGHT THROUGH NEXT
WEEK...WITH SOME THUNDERSTORM CHANCES AT TIMES - MAINLY IN THE
SOUTHERN HALF OF THE STATE.
THE BEST CHANCES OF RAIN APPEAR TO BE IN THE SUNDAY NIGHT THROUGH
WEDNESDAY NIGHT TIME FRAME.
WIDESPREAD TOTAL 5-DAY RAINFALL AMOUNTS OF 0.5 TO 1.5 INCHES ARE
POSSIBLE OVER WESTERN AND CENTRAL NORTH DAKOTA FROM SATURDAY NIGHT
THROUGH THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1219 AM CDT SAT MAY 3 2014
AN AREA OF LIGHT RAIN SHOWERS AND MVFR CIGS WILL ARRIVE INTO KISN
AND KDIK BETWEEN 09Z-11Z SATURDAY AND CONTINUE UNTIL 15Z SATURDAY.
THEREAFTER...A VCSH WILL BE MAINTAINED AT KDIK WITH DRY
CONDITIONS ELSEWHERE. THE NEXT SURGE OF RAIN WILL MOVE INTO KDIK
BY 04Z SUNDAY WITH ANOTHER ROUND OF MVFR CIGS. OTHERWISE SCT TO
BKN LOW VFR CIGS CAN BE EXPECTED AT THE REMAINING TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...TWH
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1104 PM MDT FRI MAY 2 2014
.UPDATE...
ISSUED AT 644 PM MDT FRI MAY 2 2014
AMS HAS BECOME QUITE STABLE (SEE 00Z KUNR SOUNDING) WITH SFC HIGH
PRESSURE BUILDING INTO WRN SD SO HAVE REMOVED THUNDER FROM THE
FCST...WHILE ALSO CUTTING BACK ON POPS. REST OF FCST LARGELY
UNCHANGED.
&&
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 216 PM MDT FRI MAY 2 2014
20Z SURFACE ANALYSIS SHOWED COOL FRONT HAD STALLED FROM CENTRAL
MT INTO WESTERN NE INTO NORTHWEST IA. WEAK HIGH PRESSURE BUILDING
BEHIND IT. SHORTWAVE ENERGY OVER NORTHEAST MT/ND SUPPORTING BAND
OF POST FRONTAL -SHRA FROM EASTERN MT INTO CENTRAL SD...BUT HAVING
A BIT OF TROUBLE MAINTAINING THEMSELVES GIVEN DRIER AIR OVER THE
CWA. ACTIVITY MAY YET EXPAND PER LOCAL WRF/18Z RAP LATE THIS
AFTERNOON/EARLY THIS EVENING AS WEAK MLCAPE DEVELOPS AND SHORTWAVE
ENERGY RUSHES PAST. LOWS TONIGHT WILL BE NEAR GUIDANCE.
SATURDAY...FRONTAL BOUNDARY WILL MOVE LITTLE AS LOW LEVEL BAROCLINIC
ZONE REMAINS STRETCHED FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA.
COUPLE OF SHORTWAVES WILL MOVE NORTH OF CWA BRINGING JUST ENOUGH
FORCING FOR A FEW -SHRA/DIURNALLY DRIVEN -TSRA GIVEN WEAK MLCAPE.
ACTIVITY WILL HAVE BEST CHANCE OVER THE FAR NORTH SATURDAY NIGHT AS
LOW LEVEL FLOW BECOMES UPSLOPE AND BEST WAVE MOVES ACROSS ND.
TEMPERATURES WILL BE TRICKY GIVEN CLOUD COVER/TIGHT ISOTHERMS...SO
TRENDED COOLISH IN THE NORTH AND WARMISH IN THE SOUTH/WEST.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 216 PM MDT FRI MAY 2 2014
WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A
VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP
CHANCES TO THE AREA. FOR THE MID-WEEK...A SPLIT FLOW TROF IS
PROGGED TO CROSS THE ROCKIES WITH STRONGER SWRLY FLOW
DEVELOPING...BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. DRIER
WEATHER MAY RETURN LATER IN THE WORK WEEK...BUT WILL LEAVE SLIGHT
CHANCE POPS FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1101 PM MDT FRI MAY 2 2014
ISOLD -SHRA POSSIBLE LATE TONIGHT AND THROUGH THE DAY SATURDAY...MAINLY
ACROSS NWRN SD...PRODUCING BRIEF MVFR CONDITIONS. ISOLD AFTN/EVE
TSTMS ARE ALSO POSSIBE. SOME MVFR STRATUS POSSIBLE LATE TONIGHT
AND THROUGH THE SATURDAY...MAINLY ON THE SD PLAINS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...JOHNSON
SHORT TERM...HELGESON
LONG TERM...13
AVIATION...JOHNSON
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
235 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 235 AM CDT SAT MAY 3 2014
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP UPPER LOW JUST OFF THE PACIFIC NORTHWEST COAST...
RIDGING ENCOMPASSING MUCH OF THE WESTERN U.S....AN UPPER LOW OVER
LAKE WINNIPEG AND A SHORTWAVE TROUGH IN EASTERN WI. SUBSIDENCE
AND DRYING IN THE WAKE OF THIS SHORTWAVE TROUGH...AS SEEN FROM 00Z
MPX AND ABR SOUNDINGS AS WELL AS 11-3.9UM IMAGERY AND SURFACE
OBSERVATIONS...HAS RESULTED IN CLEARING SKIES ACROSS THE FORECAST
AREA. HAVE SEEN SOME SPOTTY FOG FORM ACROSS WI AS A RESULT OF THE
RECENT RAIN...CLEARING AND LIGHT WINDS. WEST OF THE MS RIVER
PLENTY OF MIXING EXISTS TO KEEP FOG FROM FORMING. UPSTREAM...MORE
CLOUDS WERE SPREADING OUT OF THE NORTHERN PLAINS AND MANITOBA INTO
MINNESOTA...AHEAD OF THE LAKE WINNIPEG UPPER LOW. NO PRECIPITATION
WAS FALLING OUT OF THESE...THOUGH. DESPITE THE PASSAGE OF A COLD
FRONT LAST EVENING...AIRMASS CONTINUES TO GRADUALLY MODIFY ACROSS
THE UPPER MIDWEST. 925MB TEMPS AT 00Z RANGED FROM 8-10C ACROSS THE
FORECAST AREA TO 10-13C OVER THE NORTHERN PLAINS.
ATTENTION FOR THE SHORT TERM IS MOSTLY ON THE LAKE WINNIPEG UPPER
LOW...AND A 110 KT UPPER JET STREAK ON ITS SOUTHWEST SIDE. MODELS
ARE IN GOOD AGREEMENT TRACKING THE UPPER LOW ACROSS LAKE SUPERIOR
TONIGHT...WHICH MEANS THE UPPER JET STREAK TRAVELS ACROSS NORTHERN
PORTIONS OF MN AND WI. THROUGH ABOUT 06Z SUNDAY...MUCH OF THE
FORECAST AREA ENDS UP IN THE RIGHT EXIT REGION...MAINTAINING
SUBSIDENCE. DESPITE BEING IN THE RIGHT EXIT REGION TODAY...THE
03.00Z GFS PRODUCES LIGHT QPF ACROSS MUCH OF WISCONSIN...WHILE THE
03.00Z SPCWRF-NMM PRODUCES SHOWER ACTIVITY ACROSS MUCH OF THE
FORECAST AREA LATE THIS AFTERNOON INTO THIS EVENING. 03.00Z GFS/NAM
AND LATEST RAP MODEL SOUNDINGS ALL DEPICT LESS THAN 100 J/KG OF CAPE
DEVELOPING THIS AFTERNOON BELOW THE SUBSIDENCE PRODUCED BY THE RIGHT
EXIT REGION...WITH A COLD FRONT COMING THROUGH TO AID IN DEVELOPMENT
OF SHOWERS. THERE ARE ALSO SUGGESTIONS OF A WEAK MID-LEVEL
FRONTOGENETIC ZONE ACROSS SOUTHERN MN...NORTHERN IA AND FAR
SOUTHWEST WISCONSIN AT 00Z TO AID IN SHOWER DEVELOPMENT. BASED ON
THE ABOVE...HAVE DECIDED TO EXPAND THE MENTION OF SHOWERS THROUGH
MUCH OF THE AREA THIS AFTERNOON INTO EARLY THIS EVENING. LOSS OF
DIURNAL HEATING SHOULD CAUSE SHOWERS TO WEAKEN LATE IN THE EVENING.
AS WE APPROACH 12Z SUNDAY...MUCH OF THE FORECAST AREA ENDS UP IN THE
RIGHT ENTRANCE REGION...ALONG WITH STRENGTHENING LOW TO MID LEVEL
FRONTOGENESIS. THESE FORCING FEATURES SHOULD ALLOW FOR A BAND OF
RAIN TO DEVELOP OVER SOUTHERN MN AND NORTHERN IA. FOR SOME REASON
THE 03.00Z GFS IS THE ONLY MODEL NOT PRODUCING QPF OR MUCH
LIFT...DESPITE HAVE A DECENT FRONTOGENETIC SIGNAL. MEANWHILE...THE
REGIONAL CANADIAN...NAM AND ECMWF ALL DEPICT A BAND OF RAIN ALONG
THE MN/IA BORDER 09-12Z SUNDAY. HAVE DISCOUNTED THE GFS IDEA AND
BOOSTED PRECIPITATION CHANCES TOWARDS 50 IN THE MITCHELL IOWA
COUNTY VICINITY.
DESPITE AN INFLUX OF SOME CLOUDS TODAY...THERE SHOULD BE ENOUGH SUN
AROUND TO COMBINE WITH 925MB TEMPS OF 7-10C AT 18Z TO BOOST HIGHS
INTO THE MID 50S TO LOW 60S. LOOKS BREEZY AS WELL WITH 925MB WINDS
BLOWING AT 20-25 KT. PASSAGE OF COLD FRONT WITH ALLOW COLDER LOW
LEVEL CANADIAN AIR TO INFILTRATE THE REGION. 925MB TEMPS FALL TO
0-4C BY 12Z SUNDAY. CLOUDS FROM THE F-GEN AND A BREEZE TURNING
NORTHERLY WILL HELP WITH MIXING AND TO KEEP TEMPERATURES UP
SOME...BUT ANTICIPATE LOWS IN THE 30S IN MOST LOCATIONS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 235 AM CDT SAT MAY 3 2014
STARTING OFF WITH SUNDAY...MUCH OF THE FORECAST AREA LIES IN THE
RIGHT ENTRANCE REGION WITH A LOW TO MID-LEVEL FRONTOGENESIS ZONE
ACROSS LOCATIONS SOUTHWEST OF I-94. SIMILAR TO LATE TONIGHT...THE
03.00Z GFS DEPICTS VERY LITTLE PRECIPITATION WITH THIS
FORCING...WHEREAS THE 03.00Z NAM/REGIONAL CANADIAN/ECMWF ALL HAVE A
BAND OF RAIN OVER SOUTHERN MINNESOTA...NORTHEAST IOWA AND FAR
SOUTHWEST WI. HAVE FOLLOWED THE MAJORITY AND KEPT PRECIPITATION
CHANCES HIGH...60-70 PERCENT...OVER THIS ZONE. THIS BAND OF RAIN
LOOKS TO BE MOSTLY A MORNING IMPACT AS THE RIGHT ENTRANCE REGION
SHIFTS QUICKLY OFF TO THE EAST AND THE FRONTOGENESIS ZONE WEAKENS.
AFTER 18Z SUNDAY...THE FORECAST AREA SHOULD BE DRY. TEMPERATURES ARE
LIKELY TO BE QUITE A BIT COOLER...ESPECIALLY WHERE IT RAINS...
COMPARED TO SATURDAY.
UPPER RIDGING THAT HAS BEEN STUCK OVER THE WESTERN U.S. IS THEN
PROGGED TO START PUSHING EAST TOWARDS THE REGION...FORCED BY A DEEP
TROUGH DEVELOPING ALONG THE WEST COAST BY TUESDAY MORNING. MODEL
CONSENSUS IS TO HAVE THE RIDGE AXIS OVER THE FORECAST AREA AT 00Z
WEDNESDAY. UNTIL THEN...THE AREA WILL LIE ON THE SUBSIDENT SIDE
FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THERE WERE INDICATIONS
OF POSSIBLE RAIN FROM A WEAK MID-LEVEL FRONTOGENESIS ZONE OVER THE
AREA ON MONDAY IN PAST MODEL RUNS. HOWEVER...THE 03.00Z GFS AND NAM
ARE NOW DRY. THE 03.00Z CANADIAN STILL DEPICTS A LITTLE LIGHT QPF.
HAVE DECIDED TO KEEP A 20 PERCENT CHANCE GOING...BUT IF MODEL TRENDS
CONTINUE...THESE CHANCES COULD BE REMOVED. DRY CONDITIONS SHOULD BE
THE RULE OTHERWISE FROM SUNDAY NIGHT THROUGH TUESDAY. BEING UNDER
THE INFLUENCE OF CANADIAN HIGH PRESSURE SITTING OVER UPPER
MICHIGAN...EXPECTING TEMPERATURES TO REMAIN BELOW NORMAL WITH
GRADUAL MODIFICATION EACH DAY. MONDAY NIGHT COULD GET RELATIVELY
SPEAKING CHILLY ACROSS CENTRAL WI WITH DRY AIR AND A LIGHT GRADIENT
IN PLACE.
FOR TUESDAY NIGHT AND BEYOND THROUGH THE END OF NEXT WEEK...THE
WEATHER GETS MORE ACTIVE. MUCH OF THIS IS IN RESPONSE TO THE WEST
COAST TROUGH MOVING EASTWARD...PUTTING THE AREA INTO A WARM AND
MOIST AIR ADVECTION REGIME. MODELS OVERALL ARE IN SURPRISINGLY GOOD
AGREEMENT ON THE WEST COAST TROUGH PROGRESSION...AS WELL AS THE
SURFACE LOW PRESSURE SYSTEM THAT ACCOMPANIES THE WEST COAST
TROUGH. GENERAL CONSENSUS IS FOR ELEVATED SHOWERS AND
THUNDERSTORMS TO DEVELOP OVER THE AREA TUESDAY NIGHT AS 850MB
MOISTURE TRANSPORT INCREASES AT US. 850MB COMPUTED CAPE FROM THE
03.00Z ECMWF FAIRLY IMPRESSIVE OVER IA AT 12Z WED...BETWEEN
1500-2000 J/KG. WILL NEED TO KEEP A CLOSE EYE ON LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING FOR POSSIBLE SEVERE WEATHER...WITH
LARGE HAIL THE MOST LIKELY CONCERN. ELEVATED CONVECTION PUSHES
EAST AND DIMINISHES ON WEDNESDAY... FOLLOWED BY POTENTIALLY MORE
ELEVATED CONVECTION WEDNESDAY NIGHT. POSITION OF THIS ROUND MORE
UNCERTAIN AS THE 03.00Z ECMWF IS MUCH FARTHER NORTH THAN THE
03.00Z GFS... SUGGESTING IN UPPER MI VERSUS ALONG I-90. SHOULD THE
FARTHER NORTH ECMWF OCCUR...BOTH WEDNESDAY NIGHT AND THURSDAY LOOK
QUITE WARM GIVEN HOW THE WEATHER HAS BEEN. ECMWF PUSHES LOW 80S
ACROSS MUCH OF WI FOR HIGHS ON THURSDAY. MEX GUIDANCE ACTUALLY NOT
TOO FAR OFF EITHER. COLD FRONT CROSSES SOMETIME EITHER THURSDAY OR
THURSDAY NIGHT AND THIS TIMING WILL BE CRITICAL TO SEE IF ANY
SURFACE BASED CONVECTION IMPACTS THE AREA. 03.00Z ECMWF SAYS THIS
CONVECTION FIRES EAST OF THE FORECAST AREA WHEREAS THE GFS IS MUCH
SLOWER AND MOST OF THE AREA SEES CONVECTION THURSDAY NIGHT.
NEEDLESS TO SAY 30-40 PERCENT CONSENSUS CHANCES SEEM WARRANTED.
BOTH SOLUTIONS ARE TRENDING TOWARDS COOLER AND DRIER WEATHER FOR
FRIDAY SO ONLY HAVE 20 PERCENT CHANCES THEN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1115 PM CDT FRI MAY 2 2014
SKIES HAVE CLEARED AT KRST AND SHOULD BY/AROUND 06Z AT KLSE. WINDS
HAVE GONE LIGHT/VRB AT KLSE...AND SOME CONCERN THAT IF THEY STAY
THIS WAY...THE MOIST BOUNDARY LAYER COULD RESULT IN SOME FOG
DEVELOPMENT. MIGHT GO BCFG TO COVER POTENTIAL VALLEY FOG
DEVELOPMENT. OBS WILL HAVE TO BE MONITORED CLOSELY...AND UPDATES TO
THE FORECAST AS NEEDED.
FOR SATURDAY...HIGH CLOUDS WILL BE ON THE INCREASE AHEAD OF AN UPPER
LEVEL SHORTWAVE TROUGH. EXPECTING ANY ASSOCIATED -SHRA TO STAY TO
THE NORTH. BUFKIT SOUNDINGS SUPPORT SOME MIXING THOUGH...WITH A
TIGHTER PRESSURE GRADIENT. LOOK FOR INCREASING NORTHWEST WINDS
SATURDAY MORNING...WITH AFTERNOON GUSTINESS.
&&
.HYDROLOGY...
ISSUED AT 235 AM CDT SAT MAY 3 2014
RUNOFF CONTINUES TO FILTER THROUGH THE TRIBUTARIES AND INTO THE
MISSISSIPPI RIVER. BLACK RIVER AT GALESVILLE CURRENTLY THE ONLY
TRIBUTARY SITE IN FLOOD...BUT THE STAGE IS FALLING AND SHOULD BE
BELOW FLOOD STAGE LATER THIS MORNING. ALONG THE MISSISSIPPI
RIVER...MOST LOCATIONS ARE STILL RISING. PRESENTLY WABASHA THE
ONLY SITE ABOVE FLOOD STAGE...BUT WINONA...LA CROSSE...MCGREGOR
AND GUTTENBURG DAM 10 WILL FOLLOW OVER THE NEXT FEW DAYS. STILL NO
MAJOR RAINFALL ANTICIPATED THROUGH TUESDAY...WHICH WILL HELP GET
THE TRIBUTARIES DOWN BEFORE POSSIBLY HEAVIER RAIN ASSOCIATED WITH
STORMS COMES IN TUESDAY NIGHT AND WEDNESDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RIECK
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1041 AM CDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 1035 AM CDT SAT MAY 3 2014
UPDATE WAS JUST SENT TO LOWER THIS AFTERNOONS MAX TEMPS NORTH A
DEGREE OR TWO. USING A MIXING DEPTH OF 800MB...SIMILAR TO
YESTERDAY...YIELDS SLIGHT LOWER MAX TEMPS THAN CURRENT FORECAST
SUGGESTS. ALSO OF SOME CONCERN IS THE MID LEVEL CLOUDS MOVING
SOUTHEAST THROUGH THE DAKOTAS...SOUTH OF AN H3 JET AXIS FROM NORTH
DAKOTA INTO MINNESOTA. TIGHTENING MID LEVEL BAROCLINIC ZONE
SOUTHWEST OF THE AXIS SUPPORTS THE MID DECK EXPANDING FURTHER
SOUTHEAST. LATEST RAP DATA THOUGH...KEEPS THE CLOUDS NORTHWEST OF
THE CWFA THROUGH 21Z. IF THIS TIMING VERIFIES THEN THE CLOUDS WILL
NOT HAVE A SIGNIFICANT IMPACT ON AFTERNOON TEMPERATURES.
&&
.SYNOPSIS...
ISSUED AT 310 AM CDT SAT MAY 3 2014
OTHER THAN SOME PATCHY THIN CIRRUS SKIES WERE CLEAR ACROSS THE
DVN CWA WITH WEST WINDS ABOUT 10 MPH OR LESS. 3 AM TEMPERATURES
WERE IN THE 40S TO AROUND 50.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CDT SAT MAY 3 2014
FORECAST FOCUS ON A PLEASANT DAY AHEAD THEN A SMALL CHANCE OF
SHOWERS LATE TONIGHT IN OUR NW CWA.
TODAY...AFTER HAVING SEVERAL DAYS OF WELL BELOW NORMAL TEMPERATURES
WE WILL REVERSE THAT TREND TODAY. WITH A WEAK RIDGE OF HIGH PRESSURE
PASSING TO OUR SOUTH THERE SHOULD BE MUCH MORE SUNSHINE COMPARED
TO THE PAST SEVERAL DAYS. WITH THE STRONG MAY SUN AND WEST WINDS
AFTERNOON TEMPERATURES SHOULD RISE WELL INTO THE 60S TO LOWER 70S.
THESE READINGS WILL ACTUALLY BE A COUPLE OF DEGREES ABOVE NORMAL FOR
EARLY MAY.
TONIGHT...CLOUDS WILL INCREASE AHEAD OF A WEAK UPPER LEVEL
DISTURBANCE AND ELEVATED WARM AIR ADVECTION AS NOTED ON FORECAST
SOUNDINGS. HOWEVER...MOISTURE IN THE LOW LEVELS WILL BE LIMITED SO
HAVE ONLY MENTIONED SMALL POPS FOR LATE TONIGHT IN OUR FAR NW COUNTIES...
CLOSER TO THE APPROACHING DISTURBANCE. MODELS SUGGEST FRONTOGENESIS
IN NORTHERN KS AND NW MO WITH HIGH PRESSURE IN NORTHERN MN. THIS
WILL SET UP A NICE THERMAL RIBBON DEVELOPING ACROSS THE DVN CWA
WHICH WILL IMPACT TEMPERATURES. I WILL CONTINUE TO FORECAST MINIMUM
TEMPERATURES RANGING FROM AROUND 40 ALONG HIGHWAY 20 TO NEAR 50 IN
OUR FAR SOUTHERN CWA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CDT SAT MAY 3 2014
WARMING TREND STARTING EARLY NEXT WEEK WITH EPISODES OF THUNDERSTORMS
THAT COULD BE SEVERE THE MIDDLE OF NEXT WEEK.
OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH BL MOISTURE
ISSUES THAT ARE TOO MOIST RESULTING IN TOO HIGH COVERAGE OF POPS AND
QPF AMOUNTS FOR WEAKLY FORCING SITUATIONS. RUN TO RUN VARIANCE AND
INTER SOLUTION TRENDS SUPPORTS USING A 60/40 MIX OF GFS AND HI-RES
ECMWF WITH BL TEMPS THAT MAY NEED RAISING IN WARM SECTOR BASED ON
VERIFICATION PAST 2 DAYS.
SUNDAY...HAVE TRIMMED POPS TO 20 TO 40 PERCENT OF LIGHT ELEVATED
SHOWERS NORTH AS FORCING AND MOISTURE LEVELS ARE MARGINAL WITH CLOUD
BASES AOA 5-8K AGL. SOUTH HALF OF FORECAST AREA SHOULD REMAIN DRY
WITH PARTLY CLOUDY SKIES AND MOSTLY CLOUDY SKIES NORTH. TEMPERATURES
A BIT OF A CHALLENGE WITH HIGHS LOWER TO MIDDLE 50S NORTH 1/3 TO NEAR
70F FAR SOUTH SECTIONS. NE WINDS OF 10 TO 20 MPH TO MAKE FOR A COOL
EARLY MAY DAY. ANY PRECIPITATION SHOULD SLIDE EAST BY EARLY
AFTERNOON. SUNDAY NIGHT...PARTLY TO MOSTLY CLEAR AND MINS TO SETTLE
IN THE UPPER 30S NE TO MID 40S SOUTH SECTIONS.
MONDAY AND TUESDAY...PARTLY CLOUDY WITH MID LEVEL CLOUDS AND EASTERLY
WINDS. HIGHS MOSTLY IN THE 60S ON MONDAY AND UPPER 60S TO MIDDLE
70S ON TUESDAY WITH LOWS IN THE 40S TUESDAY MORNING. COMFORTABLE
WEATHER FOR MAY.
TUESDAY NIGHT...WARM FRONT TO MOVE NORTH INTO AREA WITH FAVORABLE
FORCING FOR NOCTURNAL STORMS WITH 40+ KT LOW LEVEL JET. LOW FREEZING
LEVELS SUGGEST RISK OF LARGE HAIL AOA 1" IN DIAMETER WHICH WILL BE
MORE CLARIFIED NEXT 24 HOURS. QPF AMOUNTS GENERALLY SHOULD BE LIGHT
TO MODERATE WITH 30 TO 40 POPS REASONABLE ATTM. TEMPERATURES SHOULD
RISE DURING THE NIGHT AT MOST LOCATIONS BY MIDNIGHT.
WEDNESDAY...UNSETTLED AND RISK OF SHOWERS AND STORMS WITH SPEED OF
WARM FRONT A QUESTION. JET AXIS SUPPORTS MOST TO ALL OF AREA
SHOULD BE IN WARM SECTOR BY PM HOURS WITH HIGHS UPPER 70S TO LOWER
80S WITH DEWPOINTS TO NEAR 60 DEGREES. THIS WITH LOW LEVEL THERMAL
SHEAR PROFILES WOULD SUGGEST STRONG TO SEVERE STORM RISK. WEDNESDAY
NIGHT...MILD WITH LOWS UPPER 50S TO LOWER 60S AND POSSIBLE STORMS
DEPENDING ON HOW FAR NORTH WARM FRONT MOVES. LOW CONFIDENCE ATTM
WITH BEST ESTIMATE IS NEAR TO JUST NORTH OF HIGHWAY 20 CORRIDOR.
THURSDAY...WARM AND HUMID AND BLUSTERY WITH AFTERNOON TO EVENING
COLD FRONT TO PASS. SYNOPTIC FORCING TOOLS SUPPORTS STORMS WITH
SEVERE WITH HIGHS 75 TO 85 ATTM. LOCAL TECHNIQUES INDICATE A
TYPICAL LOW TO POSSIBLY MODERATE END SEVERE WEATHER OUTBREAK
SUGGESTED THAT SHOULD BE BETTER CLARIFIED NEXT 24 HOURS OF MAINLY
LARGE HAIL AND STRAIGHT LINE WINDS WITH ISOLATED TORNADO RISK AND
LOCALLY HEAVY RAINS. POPS MAY NEED RAISING IN THE PM HOURS. THURSDAY
NIGHT...POPS AGAIN MAY NEED RAISING WITH COOL FRONT PASSING WITH
CLEARING BY MORNING. LOWS MAY NEED TO BE LOWER IF COOL FRONT PASSES
FASTER.
FRIDAY...CLEARING WITH ANY LINGERING SHOWERS ENDING WITH NEAR
SEASONABLE TEMPERATURES WITH HIGHS AROUND 70F AND LOWS UPPER 40S TO
MIDDLE 50S FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 630 AM CDT SAT MAY 3 2014
VFR CONDS THROUGH THIS TAF CYCLE WITH MAINLY CLEAR SKIES TODAY BECOMING
CIGS AOA 7KFT THIS EVENING. VISIBILITIES WILL REMAIN P6SM THROUGH
THE PERIOD AS WELL. WEST WINDS 10 TO 20 KNOTS TODAY THEN BECOMING
NORTH TO NORTHEAST LESS THAN 10 KNOTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...NICHOLS
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
942 AM MDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 933 AM MDT SAT MAY 3 2014
JUST COMPLETED AN UPDATE. MODELS HAVE A DIFFICULT TIME RESOLVING
RATHER COMPLEX SURFACE WIND/PRESSURE PATTERN OVER THE AREA. MODELS
TENDED TO BE TOO FAR EAST AND SOUTH WITH FEATURES. RAP/HRRR HAD GOOD
HANDLE ON THE CURRENT SETUP AND USED THEM FOR THE WIND FORECAST.
IT LOOKS LIKE NOW THE FRONT WILL BE FURTHER WEST AND A LITTLE
SLOWER TO START MOVING EAST. USED THE RAP FOR THE TEMPERATURES
TODAY WITH SOME SLIGHT ADJUSTMENTS MADE TO IT BASED ON LATEST TRENDS.
LATEST NAM/SREF LOOKED VERY CLOSE TO THE RAP BY LATER TODAY AND
USED THEM TO ADJUST THE WINDS/POSITION OF THE FRONT. ALSO ADJUSTED
SKY COVER DOWN THROUGH TONIGHT WITH SOME INCREASE EXPECTED
TOMORROW. ALSO LOWERED DEWPOINTS FOR TODAY BASED ON ITS BETTER
HANDLING OF THE WIND/TEMPERATURE FIELD PLUS 12Z SOUNDINGS SHOWING
A VERY WELL MIXED AND DRY AIR MASS WITH THE LOWEST DEWPOINTS IN
THE WESTERN PORTION. FORTUNATELY THE WINDS LOOK TO STAY BELOW
CRITICAL LEVELS SINCE RELATIVE HUMIDITIES WILL HAVE NO PROBLEM
DIVING TO VERY LOW VALUES THIS AFTERNOON...ESPECIALLY OUT WEST.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 226 AM MDT SAT MAY 3 2014
UPPER FLOW WILL BE NORTHWEST OVER THE CENTRAL PLAINS TODAY WITH A
RIDGE OVER THE ROCKIES. THE RIDGE WILL MOVE INTO THE PLAINS TONIGHT
AND SUNDAY AND RESIDE THERE THROUGH MONDAY. BY MONDAY NIGHT THE
RIDGE WILL SHIFT EAST INTO THE MISSOURI VALLEY WITH SOUTHWEST FLOW
EAST OF THE ROCKIES. A SURFACE TROUGH WILL BE PRESENT THROUGH SUNDAY
NIGHT EITHER IN EASTERN COLORADO OR ACROSS WESTERN KANSAS. A FRONT
WILL PUSH SOUTH INTO NORTHWEST KANSAS MONDAY WITH HIGH PRESSURE
BUILDING IN BEHIND IT. ANOTHER TROUGH WILL MOVE INTO EASTERN
COLORADO MONDAY NIGHT.
A COUPLE OF DISTURBANCE MOVE THROUGH THE FLOW SUNDAY AND MONDAY.
MOISTURE IS INSUFFICIENT FOR BOTH OF THE WAVES AS THEY COME THROUGH.
OTHERWISE SUBSIDENCE WILL BE PRESENT OVER THE FA TODAY AND TONIGHT
AS WELL AS SUNDAY AND MONDAY NIGHTS. THE NET RESULT WILL BE DRY
CONDITIONS THROUGH THIS ENTIRE FORECAST WITH NIL POPS.
MAX TEMPERATURES SHOULD RISE TO THE MID 80S TODAY AND AROUND 90
SUNDAY AND MONDAY. MIN TEMPERATURES TONIGHT AND SUNDAY NIGHT WILL
COOL TO THE UPPER 40S. MIN TEMPERATURES MONDAY NIGHT WILL BE
SLIGHTLY WARMER AROUND 50.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 226 AM MDT SAT MAY 3 2014
BY THE START OF THE EXTENDED PERIOD A DEEP RELATIVELY SLOW MOVING
UPPER LEVEL TROUGH WILL BE LOCATED WEST OF THE ROCKIES. A LEE SIDE
SURFACE TROUGH AND DRYLINE WILL BE POSITIONED OVER EASTERN COLORADO.
BY LATE TUESDAY INTO WEDNESDAY AS THE UPPER LEVEL TROUGH NEARS...A
SURFACE LOW WILL DEVELOP OVER THE FORECAST AREA. THE DRYLINE WILL BE
POSITIONED JUST EAST OF THE AREA ACROSS CENTRAL KANSAS. THE BEST LOW
LEVEL MOISTURE WILL RESIDE EAST OF THE DRYLINE AND ACROSS THE
NORTHERN PORTION OF THE FORECAST AREA WHERE EASTERLY/NORTHEASTERLY
LOW LEVEL FLOW WILL OCCUR ON THE NORTH SIDE OF SURFACE LOW. THE BEST
CHANCES OF CONVECTION WILL BE EAST OF THE DRYLINE AND NORTH OF THE
SURFACE LOW. A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT BRINGING
COOLER TEMPERATURES. SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE
UNTIL THE UPPER TROUGH AXIS MOVES THROUGH ON FRIDAY. CRITICAL FIRE
WEATHER CONDITIONS MAY DEVELOP ACROSS THE SOUTHERN PORTION OF THE
AREA TUESDAY AFTERNOON AND AGAIN ON WEDNESDAY AFTERNOON BEHIND THE
DRYLINE AS RH VALUES DROP BELOW 15 PERCENT AND WINDS POSSIBLY REACH
CRITERIA. SOME UNCERTAINTY REMAINS WITH THE PLACEMENT OF THE DRYLINE
AND SURFACE LOW AS WELL AS WINDS. THIS WILL NEED TO BE MONITORED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 457 AM MDT SAT MAY 3 2014
VFR CONDITIONS WILL CONTINUE FOR KGLD AND KNCK FOR THE NEXT 24
HOURS. SOME HIGH CLOUDS WILL TRAVERSE THE REGION AND WINDS WILL
GENERALLY BE LIGHT AND VARIABLE AS HIGH PRESSURE BUILDS EAST FROM
THE ROCKIES INTO THE PLAINS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...FS
LONG TERM...BRB
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1041 AM EDT SAT MAY 3 2014
.SYNOPSIS...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WEAK LOW PRESSURE WILL CROSS LOWER MICHIGAN TODAY...AND SLOWLY MOVE
OFF TO THE EAST. OUR LONG PERIOD OF WET WEATHER WILL FINALLY END BY
SUNDAY AFTERNOON...AS HIGH PRESSURE BUILDS SOUTHEAST FROM CENTRAL
CANADA. COOL WEATHER WILL CONTINUE INTO EARLY IN THE WORK WEEK...BUT
THINGS WILL TURN WARMER BY THURSDAY AND FRIDAY.
&&
.UPDATE...
ISSUED AT 1041 AM EDT SAT MAY 3 2014
NW-SE ORIENTED UPPER TROUGH AXIS NOW SLIDING INTO THE GREAT LAKES.
ONE VORTICITY MAX AND ATTENDING SFC LOW/TROUGH PUSHING THROUGH
EASTERN LOWER MICHIGAN DRIVING A FAIRLY EXPANSIVE BATCH OF
RAINFALL THROUGH THE SE HALF OF THE CWA. ANOTHER STRETCHED OUT
BAND OF PRECIP EXTENDS BACK INTO CENTRAL AND EASTERN UPPER
MICHIGAN ALONG THE MID LEVEL SHEAR AXIS.
WHOLE CONGLOMERATION OF PRECIP WILL CONTINUE TO SWING EASTWARD
THROUGH THE REGION OVER THE NEXT FEW HOURS BRINGING A PERIOD OF
CATEGORICAL PRECIP TO THE CWA. BEHIND THE TROUGH...SHARP CLEARING
LINE AND DRIER AIR NOTED UPSTREAM THAT WILL SPREAD EASTWARD INTO
THE CWA DURING THE COURSE OF THE AFTERNOON (ALREADY HAPPENING IN
THE SW COUNTIES). HAVE TWEAKED POPS ACCORDINGLY. BUT...WITH -28C
OR COLDER MID LEVEL AIR SLIPPING INTO NRN MICHIGAN THIS AFTERNOON/
HEATING AND SOME RESULTING INSTABILITY...CERTAINLY THINK SHOWERS
WILL POP UP THIS AFTERNOON...LIKELY DOWNWIND OVER THE HIGHER
TERRAIN INTO THE E/S PART OF THE CWA...LASTING INTO THE EVENING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT SAT MAY 3 2014
CURRENTLY, SFC TROUGH/WEAK COLD FRONT IS BEGINNING TO MOVE ACROSS
NORTHERN LAKE MICHIGAN WITH A 500 MB SHORTWAVE TROUGH/SPEED MAX
DIVING INTO THE MAIN 500 MB TROUGH CURRENTLY OVER THE UPPER GREAT
LAKES. THERE ARE SOME SHOWERS ASSOCIATED WITH THIS WAVE. TO THE
WEST, THERE IS A DECENT AREA OF SUBSIDENCE AND DRYING IN THE UPPER
MISSISSIPPI VALLEY. THE RAIN SHOWERS AND THE DRYING WILL BE THE MAIN
CONCERNS WITH THIS PACKAGE.
TODAY...WHILE THE GFS AND ECMWF MODELS HAVE SIMILAR CONFIGURATION
WITH THE QPF, THE GFS IS MORE INTENSE, SO THINKING THAT THERE HAS
BEEN A LITTLE GRID SCALE FEEDBACK. HOWEVER, WITH THAT SAID THE MASS
FIELDS ARE COMPARABLE BETWEEN THE TWO. THE NAM LOOKS SIMILAR TO THE
GFS WITH THE SFC LOW MOVING INTO WC LOWER, AND SPREADING RAIN
FARTHER NORTH INTO THE FORECAST AREA. THE RUC13 SEEMS TO BE HANDLING
THE PRECIPITATION LIKE THE ECMWF, WHICH SEEMS TO BE FOLLOWING THE
CURRENT TRENDS OF THE RADAR ATTM. IT LOOKS LIKE THERE WILL BE A
NUMEROUS RAIN SHOWERS ALONG AND SOUTH OF M-72 AS SFC TROUGH MOVES TO
THE EAST BETWEEN US-10 AND I-96 DOWNSTATE. THERE IS A SECOND AREA OF
LIGHT RAIN BETWEEN AND KRRL AND W LAKE SUPERIOR. WHICH WILL SWEEP
THROUGH UPPER MICHIGAN AND AREAS NORTH OF M-32 THIS MORNING. BY 18Z,
THE RAIN WILL LIKELY BE ON THE EAST SIDE OF THE STATE AS THE DRY AIR
NOTED IN THE MISSISSIPPI VALLEY NOW, SHOULD BE PUSHING INTO NW LOWER
AND C UPPER.
TONIGHT...AS THE DRY AIR PUSHES THROUGH THE REGION, THERE WILL STILL
BE SOME MOISTURE IN THE LOWER LEVELS (850 MB AND LOWER RH IS AROUND
70%) AND WITH ANOTHER 500 MB SHORTWAVE TROUGH ROTATING THROUGH LAKE
SUPERIOR, THAT WE GE THE CHANCE FOR RAIN SHOWERS, MIXED WITH SOME
SNOW IN E UPPER, AS THE 850 MB TEMPERATURES FALL TO AROUND -4C WITH
THE SFC TEMPERATURES FALLING TO THE MID 30S. THERE COULD ALSO BE
SOME SNOW MIXING IN WITH THE RAIN IN THE N LOWER HIGHLANDS, AROUND
GAYLORD AS TEMPERATURES FALL TO THE MID 30S THERE AS WELL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 331 AM EDT SAT MAY 3 2014
THERE APPEAR TO BE ACTUAL CHANGES ON THE HORIZON. UPPER FLOW FINALLY
GETS UNSTUCK AND BECOMES MORE PROGRESSIVE. AFTER ONE FINAL SHORTWAVE
SQUEEZES BY SUPERIOR/EASTERN UPPER MI EARLY SUNDAY...RIDGING OUT
WEST WILL SLOWLY BUILD EAST INTO THE PLAINS AND UPPER MS VALLEY. AT
THE SURFACE...WEAK HIGH PRESSURE NOSES IN FROM THE NW...AND HANGS
OUT THRU MONDAY. THE AIRMASS IS INITIALLY STILL QUITE COOL...AND
SUBSTANTIAL WARM ADVECTION WILL NOT BE SEEN AT LOW LEVELS UNTIL
LATER IN THE WEEK. BUT OUR AIRMASS WILL MODERATE IN PLACE AS EARLY
MAY SUNSHINE FINALLY GETS A CHANCE TO DO SOMETHING. SO SUNNIER AND
MILDER WX IS IN STORE EVENTUALLY...THOUGH THE NIGHTS WILL STILL BE
SEASONABLY COOL.
SUNDAY...ANOTHER SHOT OF COLD ADVECTION WILL BE UNDERWAY AT THE
START OF THE DAY...BEHIND A COLD FRONT ADVANCING INTO SOUTHERN LOWER
MI. A FAIRLY POTENT 500MB VORT RIBBON WILL EXTEND FROM ISLE ROYALE
TO CENTRAL LAKE HURON IN THE MORNING. IT/S PROGRESS EASTWARD WILL
SET US UP FOR SUBSTANTIAL NVA AND DEEP DESCENT BY MID/LATE
AFTERNOON. BUT UNTIL THEN...WE/LL BE FIGHTING OFF A SHOWER THREAT
FOR A FEW MORE HOURS. BEST CHANCE FOR PRECIP SHOULD BE BENEATH AND
NORTH OF THE VORT RIBBON. SOME DPVA DYNAMICS WILL BE FOUND BENEATH
THE RIBBON. TO THE NORTH...WE WILL SEE THE COLDEST TEMPS ALOFT (-32C
AT 500MB OVER EASTERN UPPER AT 12Z) AND CORRESPONDING STEEP LAPSE
RATES (700-500MB LAPSE RATES 7.5-7.75C/KM). SOME POTENTIAL FOR MIXED
PRECIP OVER EASTERN UPPER AND ESPECIALLY THE HIGH TERRAIN OF
NORTHERN LOWER MI...WHERE THE MELTING LAYER LOWERS TO AROUND 1K FT
THICK. WILL CUT OFF PRECIP AT 16Z...THOUGH COLD-AIR CUMULUS WILL
MAINTAIN PARTLY TO MOSTLY CLOUDY SKIES. THE CHILLY AIRMASS (850MB
TEMPS -3 TO -4C) AND LIMITED SUNSHINE WILL KEEP MAX TEMPS IN THE
UPPER 40S TO LOWER 50S...PERHAPS A BIT WARMER IN THE FAR SE.
SUN NIGHT/MONDAY...WITH LOSS OF HEATING...CU FIELD SHOULD DIMINISH
WITH TIME SUNDAY EVENING IN NORTHERN LOWER. SOME SIGNS OF MSLP
TROFFING AND ASSOCIATED 1000-850MB CONVERGENCE HANGING AROUND
EASTERN UPPER FOR MUCH OF THE NIGHT. THAT WOULD HELP SOME RESIDUAL
STRATOCU LINGER FOR MUCH OF THE NIGHT OVER FAR NORTHERN LOWER AND
POINTS NORTH. THE ARRIVAL OF BUBBLE HIGH PRESSURE SHOULD DIMINISH
THE LOW CLOUD PRESENCE ON MONDAY. HOWEVER...THE LEFTOVER FRONT FROM
THE OHIO VALLEY INTO THE DAKOTAS WILL BECOME MORE ACTIVE...WITH SOME
ASSOCIATED HIGH CLOUD DEBRIS ENTERING THE REGION FROM THE WEST.
STILL...THINGS LOOKS PARTLY SUNNY AT WORST.
MIN TEMPS IN THE UPPER 20S TO LOWER 30S...THOUGH SOME OF THE USUAL
COLD SPOTS WILL DIP A LITTLE LOWER. MAX TEMPS 50 TO 60F.
REST OF THE FORECAST...UPSTREAM 500MB RIDGE AXIS WILL AMPLIFY A BIT
BY THE TIME IT MOVES OVERHEAD EARLY THURSDAY. AN UPPER LOW STALLED
OVER THE CANADIAN PRAIRIE WILL EVENTUALLY HELP PUSH THE RIDGE EAST
AND/OR SUPPRESS IT TOWARD NEXT...THOUGH THE MANNER IN WHICH THIS
HAPPENS IS STILL UNCERTAIN. REGARDLESS...THIS IS A MUCH WARMER
PATTERN...AND TEMPS WILL CLIMB AS WE PROGRESS THRU THE WORK WEEK.
HOWEVER...THE EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING MCS/S
INTO THE RIDGE AXIS BEGINNING AS SOON AS WED NIGHT. THIS HAS CLEAR
POTENTIAL TO MESS UP OTHERWISE WARM WX...AND WILL NOT GO WILD WITH
MAX TEMPS LATE IN THE WEEK AT THIS TIME.
AS FOR PRECIP...INITIAL SURGE OF WARM ADVECTION COULD PRODUCE SOME
SHRA ON WED (THOUGH WILL LEAVE OUT THUNDER). THINGS GRADUALLY GET
STORMIER INTO THURSDAY/THU NIGHT. FRIDAY LOOKS HIGHLY UNCERTAIN AS
THIS TIME...DEPENDING ON TIMING WE MAY TRY TO DRY OUT BEHIND A WEAK
COLD FRONT (ECMWF) OR NOT SEE FROPA UNTIL FRIDAY NIGHT (GFS). SO
CHANCY POPS STILL IN ORDER THAT FAR OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM EDT SAT MAY 3 2014
VARIABLE CONDITIONS CONTINUE...THOUGH IN GENERAL IMPROVEMENT IS
EXPECTED.
WEAK LOW PRESSURE WILL MOVE EAST ACROSS LOWER MI TODAY. SHRA AND
OCCASIONAL CIG/VSBY RESTRICTIONS WILL CONTINUE TODAY...MAINLY
THIS MORNING. APN WILL TEND TO BE MVFR MOST OF THE DAY...AND PLN
WILL START OUT IFR AND TREND TO MVFR. TVC/MBL WILL BE BETTER
OFF...MOSTLY VFR BUT PERHAPS MVFR AT TIMES. ALL SITES WILL TEND TO
VFR TONIGHT...THOUGH SOME LOWER (MVFR) CIGS MAY REACH PLN AT
MORNING AS COOLER AIR FILTERS BACK IN.
WESTERLY BREEZE THRU THE FORECAST.
&&
.MARINE...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WINDS TODAY WILL BEGIN TO VEER IN THE AFTERNOON AS THE FRONT MOVES
THROUGH THE REGION, AND ONCE WINDS ARE OUT OF THE NW THEY SHOULD
INCREASE A BIT TONIGHT. HOWEVER, THE PRESSURE GRADIENT BEGINS TO
TIGHTEN AND THE FAVORED COASTAL CONVERGENCE AREA, FROM THE MACKINAC
BRIDGE TO PRESQUE ISLE LIGHT WILL PROBABLY SEE SMALL CRAFT GUSTS AND
POSSIBLY WAVES EARLY ON SUNDAY, THEN AS THE HIGH BUILDS INTO THE
UPPER GREAT LAKES IN THE AFTERNOON AND NIGHT, THE WINDS WILL
DIMINISH.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...ADAM
SYNOPSIS...JZ
SHORT TERM...JL
LONG TERM...JZ
AVIATION...JZ
MARINE...JL
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
659 AM EDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT SAT MAY 3 2014
WV IMAGERY AND RUC ANALYSIS SHOW AN UPPER TROUGH SITUATED OVER THE
GREAT LAKES REGION...WHILE AN UPPER RIDGE IS LOCATED OVER THE
WESTERN CONUS. THERE ARE A COUPLE EMBEDDED SHORTWAVES WITHIN THIS
UPPER TROUGH THAT WILL BE AFFECTING THE AREA OVER THE NEXT 24
HOURS. THE FIRST WAVE...WHICH IS CURRENTLY MOVING SOUTHEAST OUT OF
WESTERN LAKE SUPERIOR WAS PRODUCING SCATTERED/NUMEROUS SHOWERS OVER
NORTHWEST ONTARIO AND NORTHEAST MINNESOTA THIS PAST EVENING
AND IS NOW PUSHING A NORTH/SOUTH LINE OF SHOWERS ACROSS
WESTERN UPPER MICHIGAN. MODELS HAVE A GOOD AGREEMENT ON THE
EASTWARD MOVEMENT OF THESE SHOWERS AS THE FORCING FROM THE
SHORTWAVE...LEFT FRONT OF THE UPPER JET...MID LEVEL Q-VECTOR
CONVERGENCE...AND THE SURFACE TROUGH STRETCHING SOUTHWEST FROM
THE LOW CENTERED IN SOUTHERN HUDSON BAY MOVE TO THE EAST-SOUTHEAST.
RAINFALL AMOUNTS SHOULDN/T BE MUCH MORE THAN 0.05 TO 0.15 WITHIN
THE HEAVIEST PART OF THESE SHOWERS...WHICH IS SIMILAR TO THE 0.13
INCH RECEIVED AT IRONWOOD AWOS.
BEHIND THE WAVE...SOME MID LEVEL DRYING SEEN UPSTREAM (ASSOCIATED
WITH Q-VECTOR DIVERGENCE) MAY LEAD TO SOME BREAKS IN THE CLOUDS OVER
THE WESTERN CWA (ESPECIALLY NEAR THE WISCONSIN BORDER) AND HAVE
TRENDED TOWARDS A MUCH DRIER FORECAST THAN PREVIOUSLY SHOWN DURING
THE AFTERNOON. THAT IDEA FOLLOWS QPF OUTPUT BY THE MODELS FOR
WESTERN UPPER MICHIGAN...BEFORE THE NEXT WAVE APPROACHES AND BRINGS
INCREASING MID LEVEL MOISTURE FOR TONIGHT. IR SATELLITE AND SURFACE
OBS INDICATE A POCKET OF LOW LEVEL MOISTURE OVER NORTHEAST MINNESOTA
AND NORTHWEST ONTARIO THAT IS PRODUCING CEILINGS AT OR BELOW 1KFT.
THIS COMPLICATES THE SKY COVER FORECAST...AS MODELS INDICATE THIS
LOW CLOUD DECK WILL MOVE INTO THE WESTERN U.P. OVER THE NEXT COUPLE
OF HOURS (STARTING TO SEE HINTS OF IT AT KIWD AT 4AM). WILL
CONTINUE TO HAVE THOSE CLOUDS THROUGH MOST OF THE MORNING BEFORE
THE MODELS SHIFT THE MOISTURE NORTHEAST AND INCREASED MIXING
DEVELOPS. EXPECT THIS NORTHEAST MOVEMENT TO PRODUCE SOME PARTLY
CLOUDY SKIES OVER PORTIONS OF SOUTHWEST UPPER MICHIGAN...ESPECIALLY
ALONG THE WISCONSIN BORDER. THE INCREASE IN MIXING TODAY WILL
PRODUCE SOME GUSTY WEST-NORTHWEST WINDS OVER THE WESTERN 2/3RDS OF
THE CWA BEHIND THE TROUGH. TRENDED WINDS UP IN THOSE AREAS DUE TO
BETTER MIXING SHOWN ON 00Z MODEL RUNS. EXPECT SUSTAINED WINDS IN THE
10-15MPH RANGE WITH GUSTS OF 20-25MPH TO MAYBE EVEN 30MPH OVER THE
KEWEENAW PENINSULA. THESE INCREASED WINDS AND SLIGHTLY DRYER LOW
LEVEL AIR SHOULD HELP TO SCOUR OUT ANY REMAINING FOG OVER THE
EASTERN U.P. THIS MORNING. DID LINGER SOME FOG OVER CENTRAL/EASTERN
PORTIONS OF LAKE SUPERIOR...BUT SHOWED A DIMINISHING TREND WITH THE
DRIER WESTERLY FLOW. FINALLY...HIGHS TODAY LOOK TO BE IN THE UPPER
40S TO LOW/MID 50S...WITH THE HIGHEST VALUES NEAR THE WISCONSIN
BORDER UNDER THE EXPECTATIONS OF SOME SUNSHINE IN THE AFTERNOON.
THE SECOND WAVE...CURRENTLY NORTH OF LAKE WINNIPEG...IS EXPECTED
TO IMPACT THE AREA LATE THIS AFTERNOON AND INTO TONIGHT. WITH THE
TRACK OF THE WAVE AND ITS MERGING WITH ENERGY ROUNDING THE UPPER
RIDGE...THERE IS THE POTENTIAL FOR A FEW SHOWERS ALONG THE
WISCONSIN BORDER LATE THIS AFTERNOON AND THROUGH THE EVENING HOURS.
CONFIDENCE IS LOW ON THE RAIN POTENTIAL...DUE TO MID LEVEL Q-VECTOR
DIVERGENCE...AND WITH LIMITED MODEL QPF AMOUNTS...OPTED TO STICK
WITH SLIGHT AND LOW CHANCE POPS. THE OTHER OPPORTUNITY FOR
PRECIPITATION WILL COME LATE TONIGHT AND INTO SUNDAY MORNING. THE
TROUGH THAT SLIDES THROUGH THE AREA THIS MORNING AND EARLY AFTERNOON
WILL BECOME A CLOSED LOW OVER SOUTHEAST ONTARIO AND SWEEP A
SECONDARY TROUGH ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT. BEST
FORCING/MOISTURE OVER NORTHEAST HALF TO THIRD OF THE CWA...CLOSER TO
THE SECONDARY SURFACE TROUGH...SO WILL KEEP CHANCE POPS OVER
NORTHEAST LAKE SUPERIOR AND LIMIT POPS OVER THE LAND AREAS NEAR
LAKE SUPERIOR TO SLIGHT CHANCES. THE LATEST TRENDS IN THE 00Z
MODELS SEEM TO DELAY THE PRECIP TOWARDS SUNDAY MORNING. IF SHOWERS
HAPPEN...DRY LOWER LEVEL AIR WILL LEAD TO COOLING OF THE COLUMN TO
THE WETBULB TEMP. WITH THE WETBULB0 VALUES AROUND
1600-3000FT THIS EVENING BEFORE FALLING TO THE SURFACE FROM
WEST TO EAST OVERNIGHT...EXPECT THE PRECIP TO BE RAIN
INITIALLY...BEFORE TRANSITIONING TO A RAIN/SNOW MIX AND EVENTUALLY
ALL SNOW (AS COLDER AIR ALOFT SLIDES SOUTHEAST OVER THE AREA). A
TIGHTENING GRADIENT AHEAD OF THE SECONDARY TROUGH WILL KEEP A STEADY
WEST TO EVENTUALLY NORTHWEST WIND GOING THROUGH THE NIGHT...WITH THE
STRONGEST WINDS NEAR LAKE SUPERIOR AND OVER THE KEWEENAW PENINSULA
TOWARDS DAYBREAK (GUSTS TO 20-25MPH). LOWS TONIGHT LOOK TO BE IN
THE LOWER 30S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EDT SAT MAY 3 2014
NAM SHOWS A BROAD 500 MB RIDGE ACROSS THE PLAINS 12Z SUN WITH A
TROUGH IN THE UPPER GREAT LAKES AND ANOTHER IN THE PACIFIC NW. THE
RIDGE AMPLIFIES WITH TIME SUN INTO MON NIGHT ACROSS THE PLAINS AS
THE TROUGH IN THE PACIFIC NW DIGS INTO THE WESTERN U.S.
LOOKS PRETTY QUIET THIS FORECAST PERIOD WITH RAIN AND SNOW SHOWERS
MOVING OUT ON SUNDAY AND WILL GO DRY SUNDAY NIGHT THROUGH MONDAY
NIGHT. DID LOWER TEMPERATURES A BIT FOR SUNDAY NIGHT WITH RIDGING
ACROSS THE AREA AND CLEAR SKIES AND LIGHT WINDS WOULD ALLOW FOR
IDEAL RADIATIONAL COOLING CONDITIONS TO SET UP. MADE A FEW TWEAKS TO
TEMPERATURES ALONG THE LAKESHORES TO ACCOUNT FOR COOLER LAKE BREEZES
COMING IN OFF THE WATER/ICE AREAS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE ACROSS THE
PLAINS WITH A TROUGH IN THE WESTERN U.S. 12Z TUE. THE RIDGE GETS
AMPLIFIED AS IT MOVES INTO THE UPPER GREAT LAKES 12Z WED WHILE THE
TROUGH DIGS INTO THE ROCKIES WITH FURTHER AMPLIFICATION OF THE
PATTERN FOR 12Z THU AS THE TROUGH MOVES SLOWLY EASTWARD. THE TROUGH
MOVES INTO THE UPPER GREAT LAKES 12Z FRI. AS THE RIDGE POKES UP INTO
THE AREA...TEMPERATURES WILL BEGIN A WARMING TREND THIS FORECAST
PERIOD. GFS AND ECMWF SHOW 850 MB TEMPERATURES UP TO 13C ON THU AND
IF WE WOULD MIX THAT DOWN TO THE SFC...WOULD GET UP INTO THE MID
70S. ONLY PROBLEM IS WARM FRONT IS TO THE SOUTH AND THERE WILL BE
PLENTY OF CLOUDS AROUND SO THOSE TEMPERATURES WILL NOT BE REALIZED.
WITH WARM SECTOR STAYING MOSTLY TO THE SOUTH...HAVING THUNDER IN
THERE FOR WED NIGHT THROUGH THU NIGHT STILL LOOKS GOOD. ALSO LOOKS
LIKE THERE COULD BE SOME HEAVY RAIN AS AREA IS NORTH OF THE WARM
FRONT ALLOWING PLENTY OF MOISTURE TO OVERRUN THE WARM FRONT AND GET
WRUNG OUT OVER THE AREA. TEMPERATURES WILL SLOWLY WARM TO NEAR
NORMAL TOWARDS THE END OF THE FORECAST PERIOD. DID GO WITH HIGHER
POPS FOR WED NIGHT THROUGH THU NIGHT WITH WARM FRONT ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 658 AM EDT SAT MAY 3 2014
THE DISTURBANCE THAT HAS BROUGHT RAIN TO ALL THREE SITES IS
SHIFTING EAST THIS MORNING AND WILL ONLY AFFECT KSAW OVER THE NEXT
COUPLE HOURS. BEHIND THIS DISTURBANCE...IFR CEILINGS HAVE SETUP AND
EXPECT THAT TO CONTINUE THROUGH MID MORNING BEFORE RISING TO MVFR
AND EVENTUALLY VFR CONDITIONS THIS AFTERNOON. EXPECT BREEZY
CONDITIONS AT ALL THREE SITES TODAY AS DAYTIME HEATING ALLOWS FOR
MIXING INTO THE HIGHER WINDS ALOFT. ANOTHER DISTURBANCE WILL
APPROACH THE AREA LATE THIS AFTERNOON AND TONIGHT. KIWD HAS THE BEST
OPPORTUNITY FOR SHOWERS...WITH CONFIDENCE LIMITED FOR OCCURRENCE AT
KCMX/KSAW. THE PRECIPITATION WILL LIKELY START AS RAIN...BUT IF IT
IS STILL OCCURRING OVERNIGHT IT WILL CHANGE TO SNOW. HAVE KEPT
CONDITIONS AT VFR AT THIS POINT DUE TO LIMITED CONFIDENCE ON
LOCATION OF THE SHOWERS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT SAT MAY 3 2014
A LOW PRESSURE TROUGH...STRETCHING SOUTHWEST FROM A PARENT LOW OVER
SOUTHERN HUDSON BAY...WILL SHIFT EAST ACROSS LAKE SUPERIOR THIS
MORNING THROUGH THE FIRST HALF OF THE AFTERNOON. AS THIS TROUGH
SHIFTS THROUGH...WINDS WILL VEER TO THE WEST AT 10-25KTS. AS THE
FIRST TROUGH CONTINUES EAST TONIGHT...A SECONDARY TROUGH WILL SLIDE
ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT INTO SUNDAY
MORNING...TURNING WINDS TO THE NORTHWEST AND REMAINING IN THE
10-25KT RANGE. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE SOUTHEAST
OVER THE UPPER GREAT LAKES REGION SUNDAY AFTERNOON AND REMAIN
THROUGH TUESDAY...KEEPING WINDS BELOW 15KTS. A LOW PRESSURE SYSTEM
LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS ON WEDNESDAY WILL LEAD
TO INCREASING SOUTHEASTERLY WINDS...BUT THEY SHOULD REMAIN BELOW
25KTS.
&&
.HYDROLOGY...
ISSUED AT 427 AM EDT SAT MAY 3 2014
STREAMS AND RIVERS WILL CONTINUE TO EXPERIENCE HIGHER LEVELS.
LOCATIONS STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE
STURGEON RIVER OVER HOUGHTON AND BARAGA COUNTIES...THE PAINT RIVER
NEAR CRYSTAL FALLS...THE STURGEON RIVER NEAR NAHMA JUNCTION AND
TAHQUAMENON RIVER NEAR PARADISE.
RIVERS OVER EASTERN UPPER MICHIGAN HAVE STARTED TO STEADY OUT
ON THEIR RISES OVER THE LAST 12 HOURS...SINCE THE HEAVIER
PRECIPITATION SEEN IN THAT AREA WEDNESDAY INTO THURSDAY HAS BEEN
WORKING THROUGH THE BASINS. WITH ONLY LIGHT RAIN EXPECTED TODAY
(GENERALLY UNDER 0.15INCH)...EXPECT THOSE RIVERS LEVELS TO BE STEADY
OR SLOWLY FALL TODAY AND INTO THE FIRST PART OF NEXT WEEK. ONE
INTERESTING ITEM TO NOTE IS THAT THE TAHQUAMENON RIVER NEAR
PARADISE IS CURRENTLY AT 9.57 FEET...WHICH IS THE 3RD HIGHEST LEVEL
ON RECORD /60 YEARS OF DATA/.
WITH A FEW INCHES OF SNOW WATER EQUIVALENT UPSTREAM OF THE STURGEON
RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER...THE
ONGOING SNOW MELT WILL CONTINUE TO FEED WATER INTO THEIR BASINS
EVEN WITH LIGHTER RAINFALL EXPECTED THROUGH SUNDAY MORNING. EXPECT
MULTIPLE DAYS WITH TEMPS IN THE 40S AND 50S THOUGH THE MIDDLE OF
NEXT WEEK TO MELT THE REMAINING SNOW. THE MELT WILL BE SLOWED DOWN
THOUGH AS NIGHTTIME TEMPS WILL STILL BE IN THE LOWER TO MIDDLE 30S.
AFTER THE RAIN THROUGH THE SUNDAY MORNING...THE NEXT CHANCE
OF WIDESPREAD RAINFALL WILL NOT OCCUR UNTIL NEXT WEDNESDAY OR
THURSDAY. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD
CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...SRF
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
653 AM EDT SAT MAY 3 2014
.SYNOPSIS...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WEAK LOW PRESSURE WILL CROSS LOWER MICHIGAN TODAY...AND SLOWLY MOVE
OFF TO THE EAST. OUR LONG PERIOD OF WET WEATHER WILL FINALLY END BY
SUNDAY AFTERNOON...AS HIGH PRESSURE BUILDS SOUTHEAST FROM CENTRAL
CANADA. COOL WEATHER WILL CONTINUE INTO EARLY IN THE WORK WEEK...BUT
THINGS WILL TURN WARMER BY THURSDAY AND FRIDAY.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT SAT MAY 3 2014
CURRENTLY, SFC TROUGH/WEAK COLD FRONT IS BEGINNING TO MOVE ACROSS
NORTHERN LAKE MICHIGAN WITH A 500 MB SHORTWAVE TROUGH/SPEED MAX
DIVING INTO THE MAIN 500 MB TROUGH CURRENTLY OVER THE UPPER GREAT
LAKES. THERE ARE SOME SHOWERS ASSOCIATED WITH THIS WAVE. TO THE
WEST, THERE IS A DECENT AREA OF SUBSIDENCE AND DRYING IN THE UPPER
MISSISSIPPI VALLEY. THE RAIN SHOWERS AND THE DRYING WILL BE THE MAIN
CONCERNS WITH THIS PACKAGE.
TODAY...WHILE THE GFS AND ECMWF MODELS HAVE SIMILAR CONFIGURATION
WITH THE QPF, THE GFS IS MORE INTENSE, SO THINKING THAT THERE HAS
BEEN A LITTLE GRID SCALE FEEDBACK. HOWEVER, WITH THAT SAID THE MASS
FIELDS ARE COMPARABLE BETWEEN THE TWO. THE NAM LOOKS SIMILAR TO THE
GFS WITH THE SFC LOW MOVING INTO WC LOWER, AND SPREADING RAIN
FARTHER NORTH INTO THE FORECAST AREA. THE RUC13 SEEMS TO BE HANDLING
THE PRECIPITATION LIKE THE ECMWF, WHICH SEEMS TO BE FOLLOWING THE
CURRENT TRENDS OF THE RADAR ATTM. IT LOOKS LIKE THERE WILL BE A
NUMEROUS RAIN SHOWERS ALONG AND SOUTH OF M-72 AS SFC TROUGH MOVES TO
THE EAST BETWEEN US-10 AND I-96 DOWNSTATE. THERE IS A SECOND AREA OF
LIGHT RAIN BETWEEN AND KRRL AND W LAKE SUPERIOR. WHICH WILL SWEEP
THROUGH UPPER MICHIGAN AND AREAS NORTH OF M-32 THIS MORNING. BY 18Z,
THE RAIN WILL LIKELY BE ON THE EAST SIDE OF THE STATE AS THE DRY AIR
NOTED IN THE MISSISSIPPI VALLEY NOW, SHOULD BE PUSHING INTO NW LOWER
AND C UPPER.
TONIGHT...AS THE DRY AIR PUSHES THROUGH THE REGION, THERE WILL STILL
BE SOME MOISTURE IN THE LOWER LEVELS (850 MB AND LOWER RH IS AROUND
70%) AND WITH ANOTHER 500 MB SHORTWAVE TROUGH ROTATING THROUGH LAKE
SUPERIOR, THAT WE GE THE CHANCE FOR RAIN SHOWERS, MIXED WITH SOME
SNOW IN E UPPER, AS THE 850 MB TEMPERATURES FALL TO AROUND -4C WITH
THE SFC TEMPERATURES FALLING TO THE MID 30S. THERE COULD ALSO BE
SOME SNOW MIXING IN WITH THE RAIN IN THE N LOWER HIGHLANDS, AROUND
GAYLORD AS TEMPERATURES FALL TO THE MID 30S THERE AS WELL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 331 AM EDT SAT MAY 3 2014
THERE APPEAR TO BE ACTUAL CHANGES ON THE HORIZON. UPPER FLOW FINALLY
GETS UNSTUCK AND BECOMES MORE PROGRESSIVE. AFTER ONE FINAL SHORTWAVE
SQUEEZES BY SUPERIOR/EASTERN UPPER MI EARLY SUNDAY...RIDGING OUT
WEST WILL SLOWLY BUILD EAST INTO THE PLAINS AND UPPER MS VALLEY. AT
THE SURFACE...WEAK HIGH PRESSURE NOSES IN FROM THE NW...AND HANGS
OUT THRU MONDAY. THE AIRMASS IS INITIALLY STILL QUITE COOL...AND
SUBSTANTIAL WARM ADVECTION WILL NOT BE SEEN AT LOW LEVELS UNTIL
LATER IN THE WEEK. BUT OUR AIRMASS WILL MODERATE IN PLACE AS EARLY
MAY SUNSHINE FINALLY GETS A CHANCE TO DO SOMETHING. SO SUNNIER AND
MILDER WX IS IN STORE EVENTUALLY...THOUGH THE NIGHTS WILL STILL BE
SEASONABLY COOL.
SUNDAY...ANOTHER SHOT OF COLD ADVECTION WILL BE UNDERWAY AT THE
START OF THE DAY...BEHIND A COLD FRONT ADVANCING INTO SOUTHERN LOWER
MI. A FAIRLY POTENT 500MB VORT RIBBON WILL EXTEND FROM ISLE ROYALE
TO CENTRAL LAKE HURON IN THE MORNING. IT/S PROGRESS EASTWARD WILL
SET US UP FOR SUBSTANTIAL NVA AND DEEP DESCENT BY MID/LATE
AFTERNOON. BUT UNTIL THEN...WE/LL BE FIGHTING OFF A SHOWER THREAT
FOR A FEW MORE HOURS. BEST CHANCE FOR PRECIP SHOULD BE BENEATH AND
NORTH OF THE VORT RIBBON. SOME DPVA DYNAMICS WILL BE FOUND BENEATH
THE RIBBON. TO THE NORTH...WE WILL SEE THE COLDEST TEMPS ALOFT (-32C
AT 500MB OVER EASTERN UPPER AT 12Z) AND CORRESPONDING STEEP LAPSE
RATES (700-500MB LAPSE RATES 7.5-7.75C/KM). SOME POTENTIAL FOR MIXED
PRECIP OVER EASTERN UPPER AND ESPECIALLY THE HIGH TERRAIN OF
NORTHERN LOWER MI...WHERE THE MELTING LAYER LOWERS TO AROUND 1K FT
THICK. WILL CUT OFF PRECIP AT 16Z...THOUGH COLD-AIR CUMULUS WILL
MAINTAIN PARTLY TO MOSTLY CLOUDY SKIES. THE CHILLY AIRMASS (850MB
TEMPS -3 TO -4C) AND LIMITED SUNSHINE WILL KEEP MAX TEMPS IN THE
UPPER 40S TO LOWER 50S...PERHAPS A BIT WARMER IN THE FAR SE.
SUN NIGHT/MONDAY...WITH LOSS OF HEATING...CU FIELD SHOULD DIMINISH
WITH TIME SUNDAY EVENING IN NORTHERN LOWER. SOME SIGNS OF MSLP
TROFFING AND ASSOCIATED 1000-850MB CONVERGENCE HANGING AROUND
EASTERN UPPER FOR MUCH OF THE NIGHT. THAT WOULD HELP SOME RESIDUAL
STRATOCU LINGER FOR MUCH OF THE NIGHT OVER FAR NORTHERN LOWER AND
POINTS NORTH. THE ARRIVAL OF BUBBLE HIGH PRESSURE SHOULD DIMINISH
THE LOW CLOUD PRESENCE ON MONDAY. HOWEVER...THE LEFTOVER FRONT FROM
THE OHIO VALLEY INTO THE DAKOTAS WILL BECOME MORE ACTIVE...WITH SOME
ASSOCIATED HIGH CLOUD DEBRIS ENTERING THE REGION FROM THE WEST.
STILL...THINGS LOOKS PARTLY SUNNY AT WORST.
MIN TEMPS IN THE UPPER 20S TO LOWER 30S...THOUGH SOME OF THE USUAL
COLD SPOTS WILL DIP A LITTLE LOWER. MAX TEMPS 50 TO 60F.
REST OF THE FORECAST...UPSTREAM 500MB RIDGE AXIS WILL AMPLIFY A BIT
BY THE TIME IT MOVES OVERHEAD EARLY THURSDAY. AN UPPER LOW STALLED
OVER THE CANADIAN PRAIRIE WILL EVENTUALLY HELP PUSH THE RIDGE EAST
AND/OR SUPPRESS IT TOWARD NEXT...THOUGH THE MANNER IN WHICH THIS
HAPPENS IS STILL UNCERTAIN. REGARDLESS...THIS IS A MUCH WARMER
PATTERN...AND TEMPS WILL CLIMB AS WE PROGRESS THRU THE WORK WEEK.
HOWEVER...THE EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING MCS/S
INTO THE RIDGE AXIS BEGINNING AS SOON AS WED NIGHT. THIS HAS CLEAR
POTENTIAL TO MESS UP OTHERWISE WARM WX...AND WILL NOT GO WILD WITH
MAX TEMPS LATE IN THE WEEK AT THIS TIME.
AS FOR PRECIP...INITIAL SURGE OF WARM ADVECTION COULD PRODUCE SOME
SHRA ON WED (THOUGH WILL LEAVE OUT THUNDER). THINGS GRADUALLY GET
STORMIER INTO THURSDAY/THU NIGHT. FRIDAY LOOKS HIGHLY UNCERTAIN AS
THIS TIME...DEPENDING ON TIMING WE MAY TRY TO DRY OUT BEHIND A WEAK
COLD FRONT (ECMWF) OR NOT SEE FROPA UNTIL FRIDAY NIGHT (GFS). SO
CHANCY POPS STILL IN ORDER THAT FAR OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 653 AM EDT SAT MAY 3 2014
VARIABLE CONDITIONS CONTINUE...THOUGH IN GENERAL IMPROVEMENT IS
EXPECTED.
WEAK LOW PRESSURE WILL MOVE EAST ACROSS LOWER MI TODAY. SHRA AND
OCCASIONAL CIG/VSBY RESTRICTIONS WILL CONTINUE TODAY...MAINLY
THIS MORNING. APN WILL TEND TO BE MVFR MOST OF THE DAY...AND PLN
WILL START OUT IFR AND TREND TO MVFR. TVC/MBL WILL BE BETTER
OFF...MOSTLY VFR BUT PERHAPS MVFR AT TIMES. ALL SITES WILL TEND TO
VFR TONIGHT...THOUGH SOME LOWER (MVFR) CIGS MAY REACH PLN AT
MORNING AS COOLER AIR FILTERS BACK IN.
WESTERLY BREEZE THRU THE FORECAST.
&&
.MARINE...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WINDS TODAY WILL BEGIN TO VEER IN THE AFTERNOON AS THE FRONT MOVES
THROUGH THE REGION, AND ONCE WINDS ARE OUT OF THE NW THEY SHOULD
INCREASE A BIT TONIGHT. HOWEVER, THE PRESSURE GRADIENT BEGINS TO
TIGHTEN AND THE FAVORED COASTAL CONVERGENCE AREA, FROM THE MACKINAC
BRIDGE TO PRESQUE ISLE LIGHT WILL PROBABLY SEE SMALL CRAFT GUSTS AND
POSSIBLY WAVES EARLY ON SUNDAY, THEN AS THE HIGH BUILDS INTO THE
UPPER GREAT LAKES IN THE AFTERNOON AND NIGHT, THE WINDS WILL
DIMINISH.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...JZ
SHORT TERM...JL
LONG TERM...JZ
AVIATION...JZ
MARINE...JL
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
543 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SAT MAY 3 2014
WATER VAPOR IMAGERY OVERLAYED WITH A RAP H5 ANALYSIS SHOWS A
RATHER EXPANSIVE UPPER LOW SPINNING TO THE SW OF HUDSON BAY WITH
AN UPPER RIDGE OVER THE ROCKIES BEGINNING TO GET FLATTENED OUT BY
AN UPPER LOW APPROACHING THE WASHINGTON/BC COAST. OUR LOCATION
BETWEEN THE HUDSON UPPER LOW AND WESTERN RIDGE HAS PLACED STRONG
NORTHWEST MID AND UPPER LEVEL JETTING ACROSS THE UPPER MIDWEST.
THIS JETTING IS IN PLACE IN RESPONSE TO A STRONG MID LEVEL THERMAL
GRADIENT THAT IS IN PLACE BETWEEN THESE TWO FEATURES AS WELL. THIS
TYPE OF WEATHER PATTERN WILL SUPPLY US WITH PLENTY OF MID AND
UPPER LEVEL CLOUD COVER THROUGH THE DAY TODAY...THAT WILL START TO
CLEAR OUT FOR ALL BUT THE SOUTHWEST TONIGHT.
BIGGEST ISSUE FOR PRECIP THIS PERIOD WILL BE LACK OF LOW LEVEL
MOISTURE...HOWEVER THERE STILL LOOKS TO BE A COUPLE OF SHOTS FOR
PRECIP. THIS FIRST WILL COME THIS AFTERNOON AND IS ASSOCIATED WITH
CLOUD COVER AND SPRINKLES OVER NW MN. THE MPX AND SPC WRFS ALONG
WITH MEMBERS 1 AND 3 OF THE HOPWRF ALL SHOW THE ADDITION OF DAYTIME
HEATING LEADING TO THE DEVELOPMENT OF ISO-SCT SHOWERS ALONG AND
EAST OF THE MISSISSIPPI RIVER...SO PULLED THE EXISTING 20 POP WE
HAD SOUTHWEST TO JUST WEST/SOUTH OF THE MS RIVER. LOOKING AT MIXED
LAYER DEWPOINTS FROM THE GFS/NAM...A RIBBON OF HIGHER MOISTURE
LOOKS TO HANG BACK ALONG THIS AXIS...ALLOWING FOR THE DEVELOPMENT
OF DIURNAL SHOWERS.
THE SECOND AND BETTER CHANCE OF PRECIP ARRIVES LATE TONIGHT AS A
ZONE OF STRONG FGEN IN THE H7-H6 LAYER ALONG WITH ISENTROPIC
UPGLIDE ON THE 305K SFC SENDS A BAND OF PRECIP FROM THE CENTRAL
ND/SD BORDER SOUTHEAST INTO NORTH CENTRAL IOWA. BY THE END OF THE
SHORT TERM...WE HAVE LIKELY POPS SHOWING UP SOUTH OF THE MN RIVER
IN ASSOCIATION WITH THIS FORCING. THE ONLY MODEL THAT DOES NOT
REALLY AGREE WITH THIS SCENARIO IS THE GFS. ALTHOUGH IT HAS THE
FGEN/ISENTROPIC FORCING...IT DOES NOT PRODUCE ANY QPF. QUICK LOOK
AT SOME RH TIME-HEIGHT CROSS SECTIONS SHOWS THE PROBLEM...THE GFS
NEVER SATURATES THE ATMO BELOW H8. GIVEN THE STRENGTH OF THE
FORCING...TEND TO BELIEVE PRECIP GENERATED WILL BE STRONG ENOUGH
TO OVERCOME THE DRY AIR SO FAVORED A NON-GFS FORECAST FOR THIS
PRECIP LATE TONIGHT.
TEMPERATURES TODAY WILL BE SIMILAR TO WHAT WAS SEEN FRIDAY AS WE
LOOK TO MIX UP TO AROUND 775 MB. ALSO SIMILAR TO YESTERDAY WILL BE
THE BREEZY CONDITIONS...THOUGH NORTHWEST WINDS WILL NOT BE QUITE
AS STRONG AS WHAT WE SAW FRIDAY OUT IN WESTERN MN. TONIGHT...
EXTENT OF CLOUD COVER WILL PLAY A LARGE ROLL IN WHERE TEMPERATURES
END UP SETTLING TO. IN THE SOUTHWEST...MAINLY CLOUDY SKIES WILL
HOLD TEMPS UP AROUND 40...BUT MOSTLY CLEAR SKIES IN THE NORTHEAST
CWA WILL ALLOW TEMPERATURES TO FALL BACK TO AROUND 30 WITH THE
PROBABILITY OF A FREEZE STEADILY INCREASING THE FARTHER NORTHEAST
YOU GET FROM I-94. AT THIS POINT...WE ARE STILL EARLY ENOUGH IN
THE GROWING SEASON NORTH OF I-94 THAT NO FROST/FREEZE PRODUCTS ARE
NECESSARY YET.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 345 AM CDT SAT MAY 3 2014
SUNDAY THROUGH TUESDAY...A FAIRLY BENIGN PATTERN WILL PERSIST FOR
THE EARLY PORTION OF THE UPCOMING WEEK DUE TO GENERALLY UPR LVL
RIDGING OVER THE CENTRAL CONUS WITH WEAK SFC PRES PATTERNS ACRS
THE REGION. SEVERAL WEAK UPR LVL DISTURBANCES WILL RIDE THE
PERIPHERY OF THE RIDGE THRU THE REGION...MAINLY LATE SUN MRNG AND
LATE SUN NIGHT...AND AFFECTING MAINLY W AND S MN WITH OCNL SHWRS
AND POSSIBLY AN ISOLD TSTM. NOT LOOKING FOR MUCH IN THE WAY OF QPF
SINCE DEEP MOISTURE IS FAIRLY CONFINED AND UPR LVL SUPPORT IS WEAK
AT BEST. DID SHOW POPS INTO THE UPR CHC AND LOW-END LIKELY RANGE
SUN MRNG DUE TO MODEL CONSISTENCY...BUT CONFIDENCE DROPS FOR SUN
NIGHT SO ONLY USED LOW-MID CHC RANGE. TEMPS WILL START A GRADUAL
WARMING TREND DURG THIS PERIOD...ESP BY TUE AS THE RIDGE IS FAIRLY
ESTABLISHED AND SLY WINDS BECOME MORE PROMINENT.
WEDNESDAY THROUGH FRIDAY...A MORE ACTIVE PATTERN IS EXPECTED AS A
LARGE UPR LVL TROF MOVING ONSHORE THE CALI COAST...SHIFTING SWD
FROM THE GULF OF ALASKA...INTERACTS WITH A DEVELOPING LOW PRES
CENTER OVER THE CO/KS REGION DURG THE DAY ON WED. AS THE LARGE
TROF DRAGS MOISTURE WITH IT FROM THE PACIFIC INTO THE CENTRAL
CONUS...AND HELPS INTENSIFY THE LOW PRES CENTER...THESE FEATURES
WILL ALL STREAM INTO THE MID-TO-UPR MISSISSIPPI RIVER VALLEY WED
INTO THU...PRODUCING PERIODS OF SCATTERED SHWRS/TSTMS FOR THE AREA
TUE NIGHT THRU THU NIGHT. THERE IS STILL MUCH UNCERTAINTY WITH
RESPECT TO THE TRACK OF THE SYSTEM AND HOW MUCH DRY AIR BECOMES
ENTRAINED INTO THE SYSTEM. THIS WILL AFFECT NOT ONLY QPF AMOUNTS
BUT ALSO THE POTENTIAL FOR ANY SEVERE WX SINCE INSTABILITY WILL BE
HIGHLY DEPENDENT ON HOW MUCH WARM-SECTORING CAN OCCUR AND IF
HIGHER LOW-LEVEL MOISTURE /DEWPOINTS/ ARE ADVECTED NWD ALONG WITH
WARMER AIR. HAVE MAINTAINED TSTM MENTION FOR THE ENTIRE CWFA.
TEMPS DO CONTINUE THEIR WARMING TREND MID-TO-LATE WEEK WITH THE
ENTIRE CWFA HAVING HIGHS CLIMB TO THE MID 60S...AND POSSIBLY INTO
THE LOWER 70S NEAR I-90.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 522 AM CDT SAT MAY 3 2014
MORE CLOUDY NORTHWEST FLOW IS EXPECTED TODAY...WITH GUSTINESS
RETURNING BY LATE MORNING...SIMILAR TO WHAT THE GFSLAMP SHOWS.
MAIN QUESTION FOR TODAY REVOLVES AROUND SHOWER POTENTIAL THIS
AFTERNOON. HRRR ALONG WITH THE HOPWRF SHOW SOME RATHER ROBUST
SHOWER ACTIVITY DEVELOPING BY THE AFTERNOON FROM STC/MSP EAST.
GIVEN THE DRY AIR AND LACK OF FORCING...THINK THIS IS A BIT
OVERDONE...BUT ENOUGH SUPPORT IS THERE TO INCLUDE A VCSH MENTION
FOR WI TERMINALS THIS AFTERNOON. TOWARD THE END OF TAF...RAIN WILL
START MOVING INTO SW MN. BEST CHANCE FOR RAIN LOOKS TO COME SOUTH
OF RWF...SO KEPT ALL TERMINALS DRY FOR THIS. GIVEN PROGRESSIVELY
DRIER FLOW...SHOULD HAVE NO PROBLEM MAINTAINING VFR CONDITIONS
THIS PERIOD.
KMSP...ONLY POTENTIAL CONCERN NOT REALLY INDICATED IN THE 12Z TAF
IS THE THREAT FOR SHOWERS THIS AFTERNOON. BASED ON THE HRRR AND
HOPWRF...BEST CHANCE FOR SOME -SHRA WILL COME BETWEEN 17Z AND 21Z.
/OUTLOOK FOR KMSP/
SUN...VFR. WINDS NE 5 KTS.
MON...VFR. WINDS E 5-10 KTS.
TUE...VFR. WINDS ESE 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JPC
AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
626 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT SAT MAY 3 2014
A FEW SPRINKLES ARE ONGOING THIS MORNING AND THE RAP MODEL
INDICATES SOME VERY WEAK MIDLEVEL FRONTOGENESIS AT THE 700-500MB
LEVEL. THIS RAIN IS INDICATIVE OF MOISTURE POOLING IN THE
NORTHWEST FLOW ALOFT AND...FOR NOW...WILL BE DISCOUNTED AS
INSIGNIFICANT.
THE RAP AND OTHER MODELS SHOW K INDICES INCREASING TO 30 TO 35C
LATE THIS AFTERNOON AND THIS EVENING ACROSS WRN NEB. THE RAP EVEN
SHOWS SOME LIFT IN THIS MOISTURE POOL AT 00Z THIS EVENING. SO
FOLLOWING THE 00Z NAM...ISOLATED SHOWERS AND THUNDERSTORMS ARE IN
THE FORECAST THIS EVENING ACROSS THE PANHANDLE AND THE WRN
SANDHILLS. ANYTHING THAT FORMS SHOULD MOVE EAST AND DECAY AROUND
03Z-06Z.
THE MODEL CONSENSUS ALSO SHOWS ISOLATED SHOWERS AND THUNDERSTORMS
WORKING INTO THE NERN ZONES TONIGHT. THE NAM SHOWS STRONG
MIDLEVEL FRONTOGENESIS ALONG AND JUST NORTH OF THE MISSOURI RIVER
SUPPORTING THIS RAIN.
HIGHS TODAY...FROM NEAR 70 IN THE NORTHEAST TO LOWER 80S
SOUTHWEST IS BASED ON A MULTI-MODEL APPROACH. THE MODELS ARE
TIGHTLY CLUSTERED AROUND 80F AT NORTH PLATTE THIS AFTERNOON. LOWS
TONIGHT FALL INTO THE 40S. A STATIONARY FRONT WILL SETTLE INTO
THE NORTH PLATTE VALLEY AND THIS SHOULD KEEP THE ATMOSPHERE WELL
MIXED WITH LOWS IN THE UPPER 40S ACROSS SRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT MAY 3 2014
LOW AMPLIFIED UPPER LEVEL RIDGE ACROSS THE SOUTHERN PLAINS WITH
NEARLY ZONAL FLOW FOR THE HIGH PLAINS ON SUNDAY. LEE SIDE TROUGH
ALONG THE FRONT RANGE WITH A COLD FRONT STALLING FROM THE HILLS
INTO N CENTRAL KS. DECENT TEMPERATURE SPREAD ACROSS THE CWA WITH
MID 60S ACROSS MUCH OF N CENTRAL NEB...WHILE FAR SW NEB WARMS
INTO THE UPPER 80S. MODELS ARE WAVERING SLIGHTLY WITH THE SW PUSH
OF THE COLD AIR...WITH SOME UNCERTAINTY TO TEMPS ACROSS THE CWA.
A LIGHT MOVEMENT EITHER WAY COULD CAUSE A 10 PLUS DIFFERENCE IN
TEMPS. ONE THING WITH HIGHER CONFIDENCE IS THE DRY AIR IN PLACE
AND PARTLY TO MOSTLY SUNNY SKIES.
BY MONDAY PACIFIC LOW WILL PUSH ONSHORE...INTO THE PACIFIC NW.
THE QUASI-STATIONARY SFC FRONT WILL STILL BE ACROSS THE AREA.
SUNNY TO MOSTLY SUNNY SKIES WILL HELP TO WARM N CENTRAL TO OR A
FEW DEGREES WARMER THAN SUNDAY. THE RIDGE AXIS IS SLIGHTLY
FURTHER EAST SO DID NOT TAKE HIGHS QUITE AS WARM IN THE SW. BY
MONDAY EVENING A WEAK DISTURBANCE WILL DRIFT EAST ACROSS S DAKOTA
AND MAY TAP PORTIONS OF NORTHERN NEB. FOR NOW HAVE LOW POPS IN
THE HIGHER TERRAIN WHERE CLOUD BASES A LITTLE LOWER AND A BETTER
CHANCE FOR ANY DEVELOPMENT TO MAKE IT THROUGH THE DRY BL.
TUESDAY WILL BE THE START OF A MORE ACTIVE PERIOD. THE PACIFIC NW
TROUGH WILL SLOWLY DIG TOWARDS THE 4 CORNERS BY THURSDAY. A
COUPLE OF MID LEVEL SHORT WAVES EJECT OVER THE AREA AHEAD OF THE
MAIN LOW. EACH WAVE WILL BRING THE CHANCE FOR STORMS. STRONG CAP
WITH LIMITED MOISTURE SO SOME CONCERNS TO HOW WIDESPREAD ANY
ACTIVITY WILL BE AND KEPT POPS AT OR LESS THAN 50 PERCENT.
MEANWHILE THE RIDGE AXIS SHIFTS EAST WITH TEMPS COOLING FROM THE
NW.
THEN FOR WED AND THURS...WITH A BETTER CHANCE FOR PRECIP EXPECTED
AND AT LEAST MORE CLOUDINESS...HAVE HIGHS IN THE UPPER 50 TO
LOWER 70S...WARMEST IN THE SOUTH. MOISTURE IS STILL A CONCERN AS
BEST MOISTURE GETS TURNED TO THE NE BEFORE MAKING IT TO THE CWA.
MODELS ARE IN BETTER AGREEMENT WITH TROUGH AXIS TO QUICKLY EJECT
ACROSS THE PLAINS ON FRIDAY AND FRIDAY NIGHT. DRY SLOT MAY PLAY
INTO THE AREA PENDING THE EXACT TRACK OF THE LOW...WHICH IS STILL
UP IN THE AIR. CURRENT THOUGH IS MORE DRY SLOT THAN NOT AND
SHOULD SEE HIGHS BACK INTO THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 626 AM CDT SAT MAY 3 2014
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT. ISOLATED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE TONIGHT...NORTH AND WEST. NORTHWEST
FLOW ALOFT WILL STEER DISTURBANCE FROM THE NRN PLAINS INTO NERN
NEB TONIGHT. THE HRRR ALSO SUGGESTS A FEW STORMS MAY FORM OFF THE
LARAMIE RANGE THIS AFTN WHICH COULD MOVE INTO WRN NEB THIS EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS MEDFORD OR
840 AM PDT SAT MAY 3 2014
.DISCUSSION...A LARGE UPPER LOW WILL BRING HIGH AND MID LEVEL
CLOUDS FOR MOST INLAND LOCATIONS AND A LOWER DECK WILL PERSIST AT
THE COAST. THE 12Z NAM AND RAP KEEP MOST PRECIPITATION TODAY
CONFINED TO THE NORTH COAST, EVEN THEN IT`S PROBABLY NOT GOING TO
AMOUNT TO MUCH IF ANYTHING. ELSEWHERE IT WILL BE DRY AND COOLER
COMPARED TO YESTERDAY. GUSTY WINDS ARE EXPECTED EAST OF THE
CASCADES, BUT THEY ARE NOT EXPECTED TO REACH ADVISORY CRITERIA.
-PETRUCELLI
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED TO BE THE PREDOMINATE
CONDITION TODAY. HOWEVER BRIEF MVFR CIGS ARE POSSIBLE ALONG THE
COAST THIS MORNING. THE MAIN CONCERN WILL BE GUSTY WINDS EAST OF
THE CASCADES LATE THIS MORNING THROUGH THE AFTERNOON. CIGS WILL
LOWER TO MVFR WEST OF THE CASCADES TONIGHT AS A COLD FRONT MOVES
INLAND. VFR CONDITIONS WILL CONTINUE EAST OF THE CASCADES THROUGH
TONIGHT. -PETRUCELLI
&&
.MARINE...UPDATED 03/0500 PDT...CONDITIONS WILL BE HAZARDOUS TO
SMALL CRAFT THIS AFTERNOON THROUGH SUNDAY. A COLD FRONT OFFSHORE
WILL ALLOW SOUTH WINDS TO INCREASE TO 15 TO 30 KT TODAY. WESTERLY
SWELL WILL ALSO INCREASE AND COMBINE WITH STEEP WIND GENERATED
WAVES. SEAS PEAK AT 12 TO 15 FEET ACROSS THE NORTH TONIGHT, WITH
SLIGHTLY LOWER SEA HEIGHTS IN THE SOUTH. MODERATE RAIN WILL
ACCOMPANY THE FRONTAL PASSAGE TONIGHT, THEN BECOME MORE SHOWERY
SUNDAY AND MONDAY. SEAS WILL EVENTUALLY EASE BELOW 10 FEET SUNDAY
NIGHT AND LOWER FURTHER EARLY NEXT WEEK. ANOTHER FRONT MAY BRING A
BRIEF PERIOD OF SIMILARLY STRONG SOUTH WINDS TO THE NORTHERN PORTION
OF THE WATERS ON THURSDAY. SPILDE
&&
.PREV DISCUSSION... /ISSUED 522 AM PDT SAT MAY 3 2014/
DISCUSSION...A LARGE UPPER LOW CONTINUES TO CHURN OFFSHORE
BETWEEN 130W AND 140W THIS MORNING. IT IS CLOSE ENOUGH TO HAVE
PRODUCED A DECENT MARINE PUSH WITH AT LEAST A BROKEN DECK OF LOW
AND MID CLOUD ALL THE WAY TO THE CASCADES NOW, BUT NOT CLOSE
ENOUGH TO BE MUCH OF A THREAT FOR PRECIPITATION. AT LEAST FOR
TODAY, THE CHANCE FOR RAIN IS MAINLY ALONG THE COAST AND OVER THE
WATERS, AND EVEN THAT IS JUST A SLIGHT CHANCE. INLAND, WE`LL SEE
ANOTHER DRY DAY WITH CLOUDS BREAKING UP LATER THIS MORNING.
TEMPERATURES WILL BE QUITE A BIT COOLER THAN WE`VE SEEN THE LAST
FEW DAYS WITH HIGHS ONLY 60S AND LOW 70S.
THE CENTER OF THE TROUGH WILL MOVE TOWARD NW OREGON AND WASHINGTON
ON SUNDAY, BUT ENOUGH ENERGY WILL MOVE THROUGH THE BASE TO PUSH A
COLD FRONT INTO SW OREGON. THE ENTIRE WEST SIDE AND MOUNTAINS WILL
LIKELY SEE RAINFALL AT SOME POINT WITH THE FRONT, BUT AS USUAL IT
WILL TAKE SOME TIME TO GET INTO THE ROGUE VALLEY. RAINFALL WILL BE
MUCH SPOTTIER ON THE EAST SIDE AND IN NORTHERN CALIFORNIA ON
SUNDAY, BUT IT DOES LOOK RATHER BREEZY IN THE AFTERNOON IN THE
USUAL SPOTS.
THE UPPER TROUGH AXIS THEN SWINGS THROUGH MONDAY AND TUESDAY AND
THIS WILL BE A SHOWERY, COOL PERIOD OVER OUR ENTIRE AREA. THERE IS
ENOUGH INSTABILITY WITH THE COLD POOL MONDAY EVENING, THAT WE
COULD SEE SOME LIGHTNING AS WELL.
NO CHANGES WERE MADE TO THE EXTENDED FORECAST THIS MORNING. A WEAK
RIDGE WILL BUILD OFF THE COAST MID NEXT WEEK AND THIS WOULD BE A
DRY PATTERN. HOWEVER, THE MODELS DO HINT AT CLOUDS AND RAIN
SPILLING OVER THE RIDGE INTO THE PACNW. TO WHAT DEGREE THIS
AFFECTS US WILL BE A FUNCTION OF THE STRENGTH OF THE RIDGE. WE`VE
GOT SLIGHT CHANCE POPS GOING AND I SEE NO REASON TO MEDDLE WITH
IT. BY THE END OF THE WEEK AND NEXT WEEK, ALL THE MODELS SUGGEST
THAT THE RIDGE BREAKS DOWN OR AT LEAST WEAKENS ENOUGH TO ALLOW
RAINFALL BACK INTO THE REGION. THIS WOULD, OF COURSE, BE FOCUSED
ON THE WEST SIDE, AND THAT IS WHERE THE HIGHEST POPS CURRENTLY
RESIDE IN OUR FORECAST. -WRIGHT
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 2 PM
THIS AFTERNOON TO 5 PM PDT SUNDAY FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT SUNDAY
FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT MONDAY
FOR PZZ350-370.
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1035 AM CDT SAT MAY 3 2014
.UPDATE...
MODELS HAVE BACKED OFF ON PRECIP CHANCES FOR TODAY. HRRR ONLY SHOWS
A FEW SHOWERS MAINLY NORTH OF MADISON AND MILWAUKEE THIS AFTERNOON.
LATEST NAM STILL INDICATES MID LEVEL FRONTOGENESIS AND STEEP LOW
LEVEL LAPSE RATES SUPPORTING SOME SHOWERS...SO ADJUSTED POPS TO
REFLECT THE HRRR. OTHERWISE DRY WEATHER EXPECTED THROUGH SUNDAY
EXCEPT IN THE SW CWA WHERE SOME LIGHT RAIN IS POSSIBLE.
&&
.AVIATION/18Z TAFS/...
A FEW SHOWERS ARE POSSIBLE ACROSS SOUTHERN WISCONSIN THIS
AFTERNOON...AND AGAIN MAINLY SOUTHWEST OF MADISON SUNDAY MORNING.
OTHERWISE...MOST PLACES WILL PROBABLY REMAIN DRY THROUGH SUNDAY.
CONDITIONS HAVE RETURNED TO VFR THIS MORNING AND SHOULD REMAIN
THAT WAY THROUGH SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT SAT MAY 3 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
PATCHY FOG EARLY THIS MORNING IN WAKE OF DEPARTING WEAK LOW
PRESSURE AND SFC FRONT. FOG MAY BE BRIEFLY DENSE BUT INCREASING
BOUNDARY LAYER WINDS SHOULD RESULT IN FOG REMAINING PATCHY. IN
ADDITION...MORE STRATUS REDEVELOPMENT LIKELY THROUGH THE EARLY
MORNING KEEPING FOG PATCHY.
ALTHOUGH SURFACE DEWPTS WL LIKELY MIX INTO THE LOW TO MID 30S
LATER THIS MRNG AND AFTN...SOME MID-LEVEL MOISTURE WILL PUSH
ACROSS SRN WI FROM THE WEST. EXPECT STEEP LOW LEVEL LAPSE RATES OF
7 TO 9 DEGREES TO DEVELOP THIS AFTN.
WEAK LAYER Q-VECTOR CONVERGENCE INDICATIVE OF WEAK CHANNELED
POSITIVE VORTICITY ADVECTION AND WEAK FRONTOGENETICAL FORCING THIS
AFTN MAY TRIGGER ISOLD TO SCT -SHRA ACROSS THE AREA INTO THE EARLY
EVENING. MESOSCALE MODEL GUIDANCE AS WELL AS SHORT TERM GUIDANCE
INDICATING SMALL THREAT SPREADING IN THIS AFTN...SO WL EXPAND LOW
POPS TO INCLUDE ENTIRE CWA INTO THE EARLY EVENING.
HIGH PRESSURE AND SUBSIDENCE SHOULD CONTRIBUTE TO ANY ISOLD -SHRA
ENDING IN THE EARLY EVENING...HOWEVER TIGHTENING BAROCLINIC ZONE
OVER FAR SRN WI LATER TONIGHT MAY ALLOW SOME -RA TO PUSH INTO
LAFAYETTE COUNTY BY 12Z/SUN.
SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
NAM/GFS SHOWING BEST 850 MB TO 700 MB FRONTOGENESIS RESPONSE
FIELDS REMAINING JUST SOUTHWEST OF THE AREA SUNDAY MORNING. THE
SOUTHWEST COUNTIES DO GET CLIPPED BY THIS FEATURE. AREA FORECAST
SOUNDINGS SHOWING A MODEST AMOUNT OF MID LEVEL MOISTURE ACROSS
THE AREA. LOW LEVELS ARE FAIRLY DRY.
WILL CONTINUE TO MENTION POPS IN THE SOUTHWEST AND FAR SOUTHERN
COUNTIES SUNDAY MORNING...AS ECMWF/CANADIAN MODELS ALSO CONTINUE
TO SHOW QPF IN THIS AREA. OTHERWISE...SKIES SHOULD BECOME PARTLY
CLOUDY BY THE AFTERNOON. ONSHORE WINDS WILL BRING COOL
TEMPERATURES NEAR THE LAKE...WITH MILDER BUT STILL BELOW NORMAL
TEMPERATURES INLAND.
HIGH PRESSURE WILL BRING QUIET WEATHER TO THE AREA SUNDAY NIGHT.
TEMPERATURES SHOULD REMAIN BELOW SEASONAL NORMALS...IN THE UPPER
30S.
THE HIGH WILL SHIFT NORTHEAST OF THE REGION...WITH WEST NORTHWEST
500 MB FLOW ALLOWING SEVERAL VORTICITY MAXIMA TO PASS THROUGH THE
AREA. AREA FORECAST SOUNDINGS FROM NAM/GFS CONTINUE TO SHOW MEAGER
MOISTURE IN THE MID LEVELS...WITH THE LOW LEVELS REMAINING DRY.
CONTINUED LOW POPS MONDAY FOR NOW...THOUGH CONFIDENCE IS MEDIUM.
MAY END UP BEING A DRY DAY IF BETTER MOISTURE DOES NOT MOVE INTO
THE AREA.
INFLUENCE OF HIGH TO THE NORTHEAST WILL BRING QUIET WEATHER TO THE
AREA MONDAY NIGHT. TEMPERATURES WILL BE COOL AGAIN...WITH LOWS IN
THE UPPER 30S.
LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF SHOW SIMILAR OVERALL TRENDS DURING THIS PERIOD...THOUGH
DIFFER AT TIMES WITH FEATURES. THEY KEEP HIGH PRESSURE INFLUENCE
TO THE NORTHEAST OF THE AREA TUESDAY...BRINGING QUIET WEATHER.
ONSHORE WINDS WILL BRING COOL TEMPERATURES NEAR THE LAKE...AND
MILDER INLAND.
500 MB RIDGE BUILDS ACROSS THE REGION TUESDAY NIGHT INTO
WEDNESDAY...WITH A TROUGH OVER THE SOUTHWESTERN USA. THIS SHOULD
BRING A LOW DEVELOPING IN THE CENTRAL PLAINS SLOWLY TOWARD
WISCONSIN DURING THIS TIME...THEN INTO WEST CENTRAL OR CENTRAL
WISCONSIN THURSDAY.
MODELS BRING A WARM FRONT NORTHWARD TOWARD THE AREA TUESDAY NIGHT
INTO WEDNESDAY...THEN THROUGH THE AREA WEDNESDAY NIGHT. SOUTHERLY
850 MB LOW LEVEL JET POINTING INTO THE REGION SHOULD BRING A FLOW
OF GULF MOISTURE NORTHWARD INTO THE AREA TUESDAY NIGHT INTO
WEDNESDAY NIGHT. 850 MB FLOW BECOMES SOUTHWEST ON
THURSDAY/THURSDAY NIGHT.
AREA FORECAST SOUNDINGS FROM GFS SHOW THE LOW TO MID LEVELS
MOISTENING UP SOMEWHAT LATER TUESDAY NIGHT INTO
WEDNESDAY/WEDNESDAY NIGHT. ELEVATED CAPES GRADUALLY INCREASE
DURING THIS TIME...THOUGH EVEN ELEVATED PARCELS ARE FIGHTING A
STRONG CAP ALOFT. CONTINUED CHANCES FOR SHOWERS AND THUNDERSTORMS
TUESDAY NIGHT INTO THURSDAY.
GFS IS ABOUT 6 TO 12 HOURS SLOWER THAN THE ECMWF WITH THE COLD
FRONTAL PASSAGE ACROSS THE AREA LATER THURSDAY NIGHT INTO FRIDAY
MORNING. AHEAD OF THE FRONT...WARM SECTOR AIRMASS WITH SOUTH TO
SOUTHWEST WINDS WILL BRING A WARM DAY TO MOST OF THE AREA. DEW
POINTS WILL ALSO RISE INTO THE LOWER 60S BY THURSDAY AFTERNOON IN
MOST AREAS.
AREA FORECAST SOUNDINGS FROM GFS SUGGEST A GOOD AMOUNT OF MEAN
LAYER CAPE WITH STRONG WIND SHEAR PROFILES. PROBLEM FOR ANY SEVERE
WEATHER POTENTIAL IS STRONG CAP OVER THE AREA...WITH 500 MB
VORTICITY MAXIMUM PASSING NORTHWEST OF THE AREA. STORMS MAY HAVE
TROUBLE MAINTAINING UPDRAFTS WITHOUT EXTRA UPWARD VERTICAL MOTION.
KEPT CHANCE POPS THURSDAY INTO THURSDAY NIGHT...WITH POPS
LINGERING INTO FRIDAY. CERTAINLY A SYSTEM/SETUP TO WATCH FOR
LATER IN THE WEEK.
AVIATION/12Z TAFS/...
PARTIAL CLEARING...LIGHT SFC WINDS...AND LINGERING LOW DEWPOINT
DEPRESSIONS BEHIND DEPARTING SFC LOW PRESSURE TROUGH WL RESULT IN
PATCHY FOG THROUGH THE EARLY MORNING. MAY BE PATCHY DENSE BUT
HOPING THAT INCREASING W-NW BOUNDARY LAYER WINDS AND SCT-BKN
STRATUS PREVENTS MORE WIDESPREAD DENSE FOG EARLY THIS MORNING.
OTHERWISE VFR CONDITIONS EXPECTED FOR MOST OF TAF PERIOD WITH A
ISOLD -SHRA TO WATCH FOR DURING THE AFTN AND EARLY EVE.
MARINE...
WILL CONTINUE SMALL CRAFT ADVY FOR GUSTY WEST WINDS DEVELOPING
THIS MRNG AND CONTINUING THIS AFTN. STRONGEST WIND GUSTS TO AROUND
25 KNOTS EXPECTED CLOSER TO SHORE DUE TO LOW LEVEL INVERSION
EXPECTED OVER THE NEAR SHORE WATERS. GL COASTAL FORECASTING SYSTEM
CONTINUES TO MEASURE SEA SURFACE WATER TEMP IN THE UPPER 30S TO
LOWER 40S. EXPECT THE WIND GUSTS TO SUBSIDE LATE THIS AFTN AND
EARLY EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
UPDATE...SM/DDV
TODAY/TONIGHT AND AVIATION/MARINE...MBK
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
642 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 235 AM CDT SAT MAY 3 2014
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP UPPER LOW JUST OFF THE PACIFIC NORTHWEST COAST...
RIDGING ENCOMPASSING MUCH OF THE WESTERN U.S....AN UPPER LOW OVER
LAKE WINNIPEG AND A SHORTWAVE TROUGH IN EASTERN WI. SUBSIDENCE
AND DRYING IN THE WAKE OF THIS SHORTWAVE TROUGH...AS SEEN FROM 00Z
MPX AND ABR SOUNDINGS AS WELL AS 11-3.9UM IMAGERY AND SURFACE
OBSERVATIONS...HAS RESULTED IN CLEARING SKIES ACROSS THE FORECAST
AREA. HAVE SEEN SOME SPOTTY FOG FORM ACROSS WI AS A RESULT OF THE
RECENT RAIN...CLEARING AND LIGHT WINDS. WEST OF THE MS RIVER
PLENTY OF MIXING EXISTS TO KEEP FOG FROM FORMING. UPSTREAM...MORE
CLOUDS WERE SPREADING OUT OF THE NORTHERN PLAINS AND MANITOBA INTO
MINNESOTA...AHEAD OF THE LAKE WINNIPEG UPPER LOW. NO PRECIPITATION
WAS FALLING OUT OF THESE...THOUGH. DESPITE THE PASSAGE OF A COLD
FRONT LAST EVENING...AIRMASS CONTINUES TO GRADUALLY MODIFY ACROSS
THE UPPER MIDWEST. 925MB TEMPS AT 00Z RANGED FROM 8-10C ACROSS THE
FORECAST AREA TO 10-13C OVER THE NORTHERN PLAINS.
ATTENTION FOR THE SHORT TERM IS MOSTLY ON THE LAKE WINNIPEG UPPER
LOW...AND A 110 KT UPPER JET STREAK ON ITS SOUTHWEST SIDE. MODELS
ARE IN GOOD AGREEMENT TRACKING THE UPPER LOW ACROSS LAKE SUPERIOR
TONIGHT...WHICH MEANS THE UPPER JET STREAK TRAVELS ACROSS NORTHERN
PORTIONS OF MN AND WI. THROUGH ABOUT 06Z SUNDAY...MUCH OF THE
FORECAST AREA ENDS UP IN THE RIGHT EXIT REGION...MAINTAINING
SUBSIDENCE. DESPITE BEING IN THE RIGHT EXIT REGION TODAY...THE
03.00Z GFS PRODUCES LIGHT QPF ACROSS MUCH OF WISCONSIN...WHILE THE
03.00Z SPCWRF-NMM PRODUCES SHOWER ACTIVITY ACROSS MUCH OF THE
FORECAST AREA LATE THIS AFTERNOON INTO THIS EVENING. 03.00Z GFS/NAM
AND LATEST RAP MODEL SOUNDINGS ALL DEPICT LESS THAN 100 J/KG OF CAPE
DEVELOPING THIS AFTERNOON BELOW THE SUBSIDENCE PRODUCED BY THE RIGHT
EXIT REGION...WITH A COLD FRONT COMING THROUGH TO AID IN DEVELOPMENT
OF SHOWERS. THERE ARE ALSO SUGGESTIONS OF A WEAK MID-LEVEL
FRONTOGENETIC ZONE ACROSS SOUTHERN MN...NORTHERN IA AND FAR
SOUTHWEST WISCONSIN AT 00Z TO AID IN SHOWER DEVELOPMENT. BASED ON
THE ABOVE...HAVE DECIDED TO EXPAND THE MENTION OF SHOWERS THROUGH
MUCH OF THE AREA THIS AFTERNOON INTO EARLY THIS EVENING. LOSS OF
DIURNAL HEATING SHOULD CAUSE SHOWERS TO WEAKEN LATE IN THE EVENING.
AS WE APPROACH 12Z SUNDAY...MUCH OF THE FORECAST AREA ENDS UP IN THE
RIGHT ENTRANCE REGION...ALONG WITH STRENGTHENING LOW TO MID LEVEL
FRONTOGENESIS. THESE FORCING FEATURES SHOULD ALLOW FOR A BAND OF
RAIN TO DEVELOP OVER SOUTHERN MN AND NORTHERN IA. FOR SOME REASON
THE 03.00Z GFS IS THE ONLY MODEL NOT PRODUCING QPF OR MUCH
LIFT...DESPITE HAVE A DECENT FRONTOGENETIC SIGNAL. MEANWHILE...THE
REGIONAL CANADIAN...NAM AND ECMWF ALL DEPICT A BAND OF RAIN ALONG
THE MN/IA BORDER 09-12Z SUNDAY. HAVE DISCOUNTED THE GFS IDEA AND
BOOSTED PRECIPITATION CHANCES TOWARDS 50 IN THE MITCHELL IOWA
COUNTY VICINITY.
DESPITE AN INFLUX OF SOME CLOUDS TODAY...THERE SHOULD BE ENOUGH SUN
AROUND TO COMBINE WITH 925MB TEMPS OF 7-10C AT 18Z TO BOOST HIGHS
INTO THE MID 50S TO LOW 60S. LOOKS BREEZY AS WELL WITH 925MB WINDS
BLOWING AT 20-25 KT. PASSAGE OF COLD FRONT WITH ALLOW COLDER LOW
LEVEL CANADIAN AIR TO INFILTRATE THE REGION. 925MB TEMPS FALL TO
0-4C BY 12Z SUNDAY. CLOUDS FROM THE F-GEN AND A BREEZE TURNING
NORTHERLY WILL HELP WITH MIXING AND TO KEEP TEMPERATURES UP
SOME...BUT ANTICIPATE LOWS IN THE 30S IN MOST LOCATIONS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 235 AM CDT SAT MAY 3 2014
STARTING OFF WITH SUNDAY...MUCH OF THE FORECAST AREA LIES IN THE
RIGHT ENTRANCE REGION WITH A LOW TO MID-LEVEL FRONTOGENESIS ZONE
ACROSS LOCATIONS SOUTHWEST OF I-94. SIMILAR TO LATE TONIGHT...THE
03.00Z GFS DEPICTS VERY LITTLE PRECIPITATION WITH THIS
FORCING...WHEREAS THE 03.00Z NAM/REGIONAL CANADIAN/ECMWF ALL HAVE A
BAND OF RAIN OVER SOUTHERN MINNESOTA...NORTHEAST IOWA AND FAR
SOUTHWEST WI. HAVE FOLLOWED THE MAJORITY AND KEPT PRECIPITATION
CHANCES HIGH...60-70 PERCENT...OVER THIS ZONE. THIS BAND OF RAIN
LOOKS TO BE MOSTLY A MORNING IMPACT AS THE RIGHT ENTRANCE REGION
SHIFTS QUICKLY OFF TO THE EAST AND THE FRONTOGENESIS ZONE WEAKENS.
AFTER 18Z SUNDAY...THE FORECAST AREA SHOULD BE DRY. TEMPERATURES ARE
LIKELY TO BE QUITE A BIT COOLER...ESPECIALLY WHERE IT RAINS...
COMPARED TO SATURDAY.
UPPER RIDGING THAT HAS BEEN STUCK OVER THE WESTERN U.S. IS THEN
PROGGED TO START PUSHING EAST TOWARDS THE REGION...FORCED BY A DEEP
TROUGH DEVELOPING ALONG THE WEST COAST BY TUESDAY MORNING. MODEL
CONSENSUS IS TO HAVE THE RIDGE AXIS OVER THE FORECAST AREA AT 00Z
WEDNESDAY. UNTIL THEN...THE AREA WILL LIE ON THE SUBSIDENT SIDE
FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THERE WERE INDICATIONS
OF POSSIBLE RAIN FROM A WEAK MID-LEVEL FRONTOGENESIS ZONE OVER THE
AREA ON MONDAY IN PAST MODEL RUNS. HOWEVER...THE 03.00Z GFS AND NAM
ARE NOW DRY. THE 03.00Z CANADIAN STILL DEPICTS A LITTLE LIGHT QPF.
HAVE DECIDED TO KEEP A 20 PERCENT CHANCE GOING...BUT IF MODEL TRENDS
CONTINUE...THESE CHANCES COULD BE REMOVED. DRY CONDITIONS SHOULD BE
THE RULE OTHERWISE FROM SUNDAY NIGHT THROUGH TUESDAY. BEING UNDER
THE INFLUENCE OF CANADIAN HIGH PRESSURE SITTING OVER UPPER
MICHIGAN...EXPECTING TEMPERATURES TO REMAIN BELOW NORMAL WITH
GRADUAL MODIFICATION EACH DAY. MONDAY NIGHT COULD GET RELATIVELY
SPEAKING CHILLY ACROSS CENTRAL WI WITH DRY AIR AND A LIGHT GRADIENT
IN PLACE.
FOR TUESDAY NIGHT AND BEYOND THROUGH THE END OF NEXT WEEK...THE
WEATHER GETS MORE ACTIVE. MUCH OF THIS IS IN RESPONSE TO THE WEST
COAST TROUGH MOVING EASTWARD...PUTTING THE AREA INTO A WARM AND
MOIST AIR ADVECTION REGIME. MODELS OVERALL ARE IN SURPRISINGLY GOOD
AGREEMENT ON THE WEST COAST TROUGH PROGRESSION...AS WELL AS THE
SURFACE LOW PRESSURE SYSTEM THAT ACCOMPANIES THE WEST COAST
TROUGH. GENERAL CONSENSUS IS FOR ELEVATED SHOWERS AND
THUNDERSTORMS TO DEVELOP OVER THE AREA TUESDAY NIGHT AS 850MB
MOISTURE TRANSPORT INCREASES AT US. 850MB COMPUTED CAPE FROM THE
03.00Z ECMWF FAIRLY IMPRESSIVE OVER IA AT 12Z WED...BETWEEN
1500-2000 J/KG. WILL NEED TO KEEP A CLOSE EYE ON LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING FOR POSSIBLE SEVERE WEATHER...WITH
LARGE HAIL THE MOST LIKELY CONCERN. ELEVATED CONVECTION PUSHES
EAST AND DIMINISHES ON WEDNESDAY... FOLLOWED BY POTENTIALLY MORE
ELEVATED CONVECTION WEDNESDAY NIGHT. POSITION OF THIS ROUND MORE
UNCERTAIN AS THE 03.00Z ECMWF IS MUCH FARTHER NORTH THAN THE
03.00Z GFS... SUGGESTING IN UPPER MI VERSUS ALONG I-90. SHOULD THE
FARTHER NORTH ECMWF OCCUR...BOTH WEDNESDAY NIGHT AND THURSDAY LOOK
QUITE WARM GIVEN HOW THE WEATHER HAS BEEN. ECMWF PUSHES LOW 80S
ACROSS MUCH OF WI FOR HIGHS ON THURSDAY. MEX GUIDANCE ACTUALLY NOT
TOO FAR OFF EITHER. COLD FRONT CROSSES SOMETIME EITHER THURSDAY OR
THURSDAY NIGHT AND THIS TIMING WILL BE CRITICAL TO SEE IF ANY
SURFACE BASED CONVECTION IMPACTS THE AREA. 03.00Z ECMWF SAYS THIS
CONVECTION FIRES EAST OF THE FORECAST AREA WHEREAS THE GFS IS MUCH
SLOWER AND MOST OF THE AREA SEES CONVECTION THURSDAY NIGHT.
NEEDLESS TO SAY 30-40 PERCENT CONSENSUS CHANCES SEEM WARRANTED.
BOTH SOLUTIONS ARE TRENDING TOWARDS COOLER AND DRIER WEATHER FOR
FRIDAY SO ONLY HAVE 20 PERCENT CHANCES THEN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 642 AM CDT SAT MAY 3 2014
A SHORT WAVE TROUGH WILL CAUSE CEILINGS TO DESCEND INTO THE 5-7K
FOOT RANGE BETWEEN 03.14Z AND 03.16Z. WHILE THE HRRR SHOWS QUITE A
FEW SHOWERS WITH THIS SYSTEM...THE OTHER MESO MODELS SHOW MUCH
LESS SHOWER ACTIVITY. DUE TO THIS...OPTED TO LEAVE THE SHOWERS OUT
OF THE TAFS AT THIS TIME. NORTHWEST WINDS WILL GUST TO AROUND
25 KNOTS THIS AFTERNOON.
THIS EVENING EXPECT SKIES TO SCATTERED OUT AT KLSE AFTER 04.00Z.
HOWEVER A BROKEN 5K DECK WILL PERSIST AT KRST.
DURING THE OVERNIGHT...THE LOWER DECK WILL BECOME SCATTERED AT
KRST. HOWEVER A 10K DECK WILL PERSIST AND THEN SPREAD INTO WESTERN
WISCONSIN AFTER 04.09Z.
&&
.HYDROLOGY...
ISSUED AT 235 AM CDT SAT MAY 3 2014
RUNOFF CONTINUES TO FILTER THROUGH THE TRIBUTARIES AND INTO THE
MISSISSIPPI RIVER. BLACK RIVER AT GALESVILLE CURRENTLY THE ONLY
TRIBUTARY SITE IN FLOOD...BUT THE STAGE IS FALLING AND SHOULD BE
BELOW FLOOD STAGE LATER THIS MORNING. ALONG THE MISSISSIPPI
RIVER...MOST LOCATIONS ARE STILL RISING. PRESENTLY WABASHA THE
ONLY SITE ABOVE FLOOD STAGE...BUT WINONA...LA CROSSE...MCGREGOR
AND GUTTENBURG DAM 10 WILL FOLLOW OVER THE NEXT FEW DAYS. STILL NO
MAJOR RAINFALL ANTICIPATED THROUGH TUESDAY...WHICH WILL HELP GET
THE TRIBUTARIES DOWN BEFORE POSSIBLY HEAVIER RAIN ASSOCIATED WITH
STORMS COMES IN TUESDAY NIGHT AND WEDNESDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS BOISE ID
1007 AM MDT SAT MAY 3 2014
.DISCUSSION...COOLER AIR FILTERING IN ALOFT AS A BROAD CLOSED LOW
APPROACHES THE PAC NW COAST. THE MORNING WEATHER BALLOON FROM
BOISE SHOWING ABOUT 5F DEGREES OF COOLING IN THE LAST 24H BETWEEN
700 AND 850 MB WHICH WILL TRANSLATE TO THE SURFACE FOR THIS
AFTERNOONS HIGHS. ONLY UPDATE TO FORECAST WAS TO SCALE BACK THE
COVERAGE OF ISOLATED SHOWERS AND ACCOMPANYING QPF ACROSS THE WEST
CENTRAL MTNS TO BE MORE IN LINE WITH THE NAM AND HRRR SOLUTIONS
FOR THIS AFTERNOON.
&&
.AVIATION...BAKER COUNTY OREGON AND THE WEST CENTRAL IDAHO
MOUNTAINS...VFR THROUGH SUNDAY MORNING...WIDESPREAD HIGH CLOUDS
LOWERING TO MID LEVELS THIS AFTERNOON. SCATTERED SHOWERS DEVELOPING
TONIGHT AND SPREADING SOUTH TO THE BOISE MOUNTAINS SUNDAY
MORNING...BECOMING MORE NUMEROUS SUNDAY AFTERNOON. ELSEWHERE IN
SOUTHEAST OREGON AND SOUTHWEST IDAHO...VFR THROUGH SUNDAY WITH AREAS
OF HIGH AND MID LEVEL CLOUDS. SURFACE WINDS...SOUTHWEST TO WEST 5-15
KTS. WINDS ALOFT...SOUTHWEST UP TO 35 KTS AT 10K FT.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH SUNDAY...HEIGHTS FALL RAPIDLY TODAY AS
RIDGE COLLAPSES AND UPPER TROUGH MOVES TOWARD THE PAC NW COAST.
SEVERAL UPPER LEVEL SHORT WAVES WILL ROTATE AROUND THE MAIN UPPER
LEVEL LOW THROUGH SUNDAY. THIS WILL PROVIDE PERIODS OF LIFT THAT
SHOULD LEAD TO SHOWERS FORMING...MAINLY IN THE NORTHERN PART OF
THE CWA AND MAINLY IN THE MTNS. TEMPS WILL REMAIN ABOVE NORMAL
TODAY WITH HIGHS IN THE MID 70S TO LOWER 80S IN THE LOWER
ELEVATIONS. THESE READINGS WILL FALL INTO THE UPPER 60S TO LOWER
70S FOR HIGHS ON SUNDAY. OVERNIGHT SAT NIGHT THE LOWS WILL BE
AROUND 50 IN THE LOWER ELEVATIONS AS CLOUD COVER AND WINDS KEEP
THE TEMP FROM DROPPING TOO FAR. THE CHANCE FOR PRECIP CLIMBS
THROUGH SUNDAY AFTERNOON AS THE VARIOUS SHORT WAVES BRING LIFT AND
ADDITIONAL MOISTURE INTO THE REGION. THERE IS MINIMAL INSTABILITY
IN THE MODELS FOR BOTH THIS AFTERNOON AND AGAIN SUNDAY...BUT AT
THIS TIME FEEL THAT IT IS NOT WORTH MENTIONING IN THE FORECAST.
LATEST SPC OUTLOOKS AGREE.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...UPPER TROUGH MOVES INTO
THE PACIFIC NORTHWEST FOR COOLER TEMPERATURES AND PRECIPITATION. A
COOL AND UNSETTLED PERIOD IS ON THE WAY FOR THE COMING WEEK. THE
UPPER LEVEL TROUGH ALONG THE COAST SUNDAY NIGHT WILL MOVE INLAND ON
MONDAY...DROPPING MAX TEMPERATURES BY 5 TO 10 DEGREES AND SPREADING
SHOWERS AND ISOLATED THUNDERSTORMS ACROSS SOUTHEAST OREGON AND
SOUTHWEST IDAHO. THE TROUGH REMAINS OVER THE AREA THROUGH
WEDNESDAY...KEEPING TEMPERATURES ABOUT 7 DEGREES BELOW NORMAL AND
A CHANCE FOR SHOWERS MAINLY OVER THE MOUNTAINS. ZONAL FLOW SETS UP
ON THURSDAY AND FRIDAY FOR A CHANCE OF MAINLY MOUNTAIN SHOWERS
AND TEMPERATURES CLOSE TO NORMAL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...DG
AVIATION.....JT
PREV SHORT TERM...SP
PREV LONG TERM....JS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
305 PM CDT SAT MAY 3 2014
.DISCUSSION...
304 PM CDT
SYNOPSIS...WINDS TURN OFF OF THE LAKE TOMORROW LEADING TO A COOLER
START TO THE WEEK. WE START A WARMING TREND MONDAY WITH STORMS
EXPECTED OVER THE LATTER HALF OF THE WEEK.
THROUGH TONIGHT...
NORTHWEST FLOW HAS SET UP ALOFT AS THE UPPER LEVEL TROUGH STRETCHES
FROM THE OHIO RIVER VALLEY THROUGH THE GULF. A CLOSED LOW IS OVER
SOUTHERN MANITOBA WHILE A BROAD SURFACE LOW IS OVER EASTERN
ONTARIO. WEST TO NORTHWEST WINDS ARE GUSTING TO 40 MPH ACROSS THE
REGION BUT EXPECTING WINDS TO DIMINISH THIS EVENING AS MIXING
EASES. AFTERNOON CU DEVELOPMENT WILL CONTINUE AND EXPECTING CLOUDS
TO REMAIN OVER THE REGION OVERNIGHT. A WEAK SURFACE TROUGH
CURRENTLY STRETCHING FROM WISCONSIN THROUGH THE MID MISSISSIPPI
VALLEY WILL ROTATE THROUGH OVERNIGHT. IT IS RATHER DRY OUT THERE
RIGHT NOW WITH DEWPOINT DEPRESSIONS AT 30+ DEGREES SO THINKING WE
WILL NOT SEE ANY SHOWERS AS THE TROUGH MOVES THROUGH. A FEW
SPRINKLES ARE POSSIBLE BUT KEPT THE FORECAST DRY AS CONFIDENCE IS
LOW.
SUNDAY AND MONDAY...
HIGH PRESSURE CONTINUES TO BUILD IN SUNDAY AND REMAINS OVER THE
REGION THROUGH TUESDAY. WINDS TURN OFF OF THE LAKE AS THE HIGH
BUILDS IN AND WILL SEE AMPLE LAKE COOLING. HAVE MAX TEMPS RANGING
FROM THE UPPER 50S TO LOW 60S IN THE OUTLYING AREAS AND UPPER 40S TO
AROUND 50 ALONG THE LAKE.
A WEAK SURFACE LOW FORMS OVER THE HIGH PLAINS TONIGHT AND ITS
STATIONARY/WARM FRONT WILL EXTEND THROUGH CENTRAL/SOUTHERN IL
THROUGH MONDAY. IN ADDITION...A WEAK VORT STREAMER TRAVELS DOWN THE
RIDGE AND OVER THE CWA SUNDAY. EXPECTING A BAND OF PRECIP TO FORM
OVER IOWA AND MOVE INTO THE REGION BY MID MORNING. THE BAND SHOULD
BE RATHER TRANSIENT AND MOVE EAST OF THE CWA IN THE LATE AFTERNOON
IF NOT EARLIER. HAVE HIGH CONFIDENCE IN THE SHOWERS OCCURRING AND
MEDIUM CONFIDENCE IN THE TIMING AND EXACT LOCATION.
HIGH PRESSURE REMAINS IN CONTROL MONDAY WITH FLOW OFF OF THE
LAKE...BUT THE WARM UP BEGINS FOR AREAS AWAY FROM THE LAKE. TEMPS
WILL ONCE AGAIN VERY FROM THE LOW TO MID 60S IN THE OUTLYING AREAS
AND IN THE LOW 50S ALONG THE LAKE. GUIDANCE HAS THE FRONT LYING
SOUTH OF THE CWA WITH SOME GUIDANCE BRINGING SOME SHOWERS INTO THE
SOUTHERN CWA. CONFIDENCE IS LOW IN THE PRECIP ACTUALLY OCCURRING SO
KEPT MONDAY DRY.
EXTENDED...TUESDAY THROUGH FRIDAY...
AN UPPER LEVEL RIDGE BUILDS OVER THE MIDWEST TUESDAY AND REMAINS
OVERHEAD THROUGH THURSDAY...WITH THE GULF OPENING UP MID WEEK. A
SECOND SURFACE LOW FORMS OVER THE PLAINS AND ITS WARM FRONT LIFTS
NORTH THROUGH THE CWA WEDNESDAY.
SHOWERS AND STORMS MOVE IN OVERNIGHT AND THINKING THE BEST CHANCE
FOR STORMS WILL BE NORTH OF I-80 WEDNESDAY AND WEDNESDAY NIGHT. THE
GFS FEATURES 1000-2000 J/KG OF CAPE AND PW AROUND 1.5 INCHES SO
STORMS ARE POSSIBLE. PW VALUES ARE 2 STANDARD DEVIATIONS ABOVE
NORMAL SO COULD SEE COPIOUS AMOUNTS OF RAIN. SHEAR VALUES WILL BE
AROUND 50 KT WITH MINIMAL CAPPING. THEREFORE SEVERE STORMS ARE
POSSIBLE.
WE REMAIN IN THE WARM SECTOR THURSDAY AND ONLY HAVE SLIGHT CHANCE TO
CHANCE POPS. THUNDERSTORMS ARE CERTAINLY POSSIBLE BUT WITHOUT A
CLEAR SOURCE OF FORCING...CONFIDENCE IS MEDIUM IN COVERAGE AND
OCCURRENCE. THE GFS CONTINUES TO SHOW INCREASED CAPPING ON THURSDAY
BUT OTHER PARAMETERS SUCH AS CAPE AND SHEAR REMAIN FAVORABLE FOR
SEVERE STORMS. WILL NOTE THAT THE CAP IS WEAKER THAN WHAT THE GFS
FEATURED YESTERDAY. DUE TO THE CONSISTENT CAP...HAVE MEDIUM
CONFIDENCE IN SEVERE STORMS ON THURSDAY.
THE COLD FRONT SWINGS THROUGH THURSDAY NIGHT INTO FRIDAY AS THE LOW
PASSES TO OUR NORTH OVER WISCONSIN. HAVE MUCH HIGHER CONFIDENCE IN
STORMS FORMING ALONG THE COLD FRONT. THE GFS IS A BIT QUICKER WITH
THE COLD FRONT BUT KEPT POPS INTO FRIDAY NIGHT.
THE GOOD NEWS IS TEMPS WILL BE WARMING THROUGH THE WEEK WITH HIGHS
AT LEAST IN THE 80S BY THURSDAY. WINDS TURN SW THURSDAY SO THERE
SHOULD NOT BE ANY LAKE COOLING. COOLING LOOKS LIMITED BEHIND THE
COLD FRONT WITH HIGHS IN THE LOW 70S.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* GUSTY WEST-NORTHWEST WINDS 25-30 KT THIS AFTN.
* NORTH WINDS 10-15 KT EARLY SUNDAY BECOMING NORTHEAST IN THE
AFTERNOON.
* PERIOD OF SHRA POSSIBLE LATE SUNDAY MORNING/EARLY
AFTERNOON...BUT WITH CIGS/VIS EXPECTED TO REMAIN VFR.
RATZER
//DISCUSSION...UPDATED 18Z...
GUSTY WEST-NORTHWEST WINDS EXPECTED TO CONTINUE THROUGH THIS
AFTERNOON AS A COMBINATION OF FAIRLY DEEP MIXED LAYER AND LOCATION
OF TERMINALS ALONG SOUTHERN PERIPHERY OF FAIRLY STRONG MID/UPPER
LEVEL JET. GRADIENT IS EXPECTED TO SLOWLY WEAKEN LATE THIS
AFTERNOON AND MORE QUICKLY THIS EVENING AS WEAK SURFACE HIGH
PRESSURE RIDGE SPREADS INTO THE AREA TONIGHT. WINDS/GUSTS EXPECTED
TO DIMINISH QUICKLY WITH SUNSET. WEAK COLD FRONT ASSOCIATED WITH
SHEARED WAVE PASSING WELL NORTH OF THE REGION THEN SAGS ACROSS THE
AREA DURING THE PRE-DAWN HOURS...RESULTING IN WIND SHIFT TO NORTH-
NORTHWEST BY MORNING INITIALLY IN THE 10-15 KT RANGE. SURFACE RIDGE
THEN BUILDS BACK INTO AREA BEHIND DEPARTING COLD FRONT...ALLOWING
WINDS TO VEER NORTHEAST BY EARLY AFTERNOON AND LIKELY MORE
EASTERLY BY SUNDAY EVENING.
ASIDE FROM WINDS...DIURNAL SCT-BKN CU WITH BASES AROUND 6000 FT
BEGINNING TO DEVELOP PER VISIBLE SAT IMAGERY THIS AFTERNOON. MORE
PREVALENT 6000-8000 FT DECK EXPECTED TO DEVELOP/EXPAND ACROSS AREA
TONIGHT INTO SUNDAY MORNING WITH WARM ADVECTION DEVELOPING ALOFT.
VARIOUS MODELS CONTINUE TO INDICATE FAIRLY HIGH POTENTIAL FOR
SHOWERS TO DEVELOP SUNDAY MORNING/MIDDAY...WITH BANDED COVERAGE
PATTERN ALONG THE NORTHWEST-SOUTHEAST THERMAL GRADIENT. BANDS
LIKELY TO BE SOMEWHAT NARROW...SO WHILE CONFIDENCE THAT SHOWERS
WILL OCCUR IS HIGH...IT IS SOMEWHAT LOWER WITH RESPECT TO TIMING
AND COVERAGE AT INDIVIDUAL POINT TERMINALS. LOW LEVELS REMAIN
RELATIVELY DRY AND CEILINGS/VIS EXPECTED TO REMAIN PRIMARILY VFR.
SHOWER THREAT DIMINISHES IN THE AFTERNOON.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN SHRA COVERAGE/EXACT TIMING AND TIMING OF
SHIFT FROM NORTH TO NORTHEAST WINDS SUNDAY.
* HIGH CONFIDENCE ALL OTHER ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...SLGT CHC FOR SHRA DURING THE AFTERNOON.
TUESDAY...CHC FOR TSRA DURING THE NIGHT.
WEDNESDAY THROUGH FRIDAY...CHC FOR TSRA.
BEACHLER
&&
.MARINE...
245 PM CDT
MODERATE WESTERLY WINDS TO AROUND 30 KT HAVE DEVELOPED ACROSS
PORTIONS OF THE UPPER MIDWEST AND GREAT LAKES THIS AFTERNOON IN THE
WAKE OF A COLD FRONT. STILL THE MARINE LAYER REMAINS FAIRLY STABLE
ACROSS LAKE MICHIGAN WHICH IS KEEPING WINDS LIGHTER AS YOU HEAD EAST
ACROSS THE LAKE. A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH
THIS EVENING FOR THE ILLINOIS NEARSHORE WATERS. WINDS SHOULD SLOWLY
TRENDS DOWN OVERNIGHT INTO SUNDAY AS HIGH PRESSURE BUILDS ACROSS THE
AREA. BY MONDAY...EXPECT LOW PRESSURE TO START TAKING SHAPE OVER THE
CENTRAL PLAINS WHICH WILL RESULT IN NORTHEAST FLOW FRESHENING UP
ACROSS LAKE MICHIGAN. THE LOW WILL FINALLY LIFT NORTHEAST INTO THE
UPPER MIDWEST LATE IN THE WEEK WITH WINDS VEERING TO THE SOUTHEAST
AS THIS OCCURS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM
SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
248 PM CDT Sat May 3 2014
.DISCUSSION...
ISSUED 235 PM CDT Sat May 3 2014
SHORT TERM...Tonight through Tuesday
Weak cold front currently located just to our northwest will swing
through the forecast area tonight and be located along the Ohio Valley
into early next week. The main forecast concern will be with any rain
chances associated along and behind the frontal boundary as a couple
of weak upper level waves track southeast over the lower Great Lakes
through Monday. Models in decent agreement with respect to the frontal
position to our south and timing of shortwave energy tracking to our
north over the next couple of days with a NAM-WRF and ECMWF preference
this forecast period.
Frontal boundary forecast to track southeast through our area tonight
with forecast soundings showing not much support for any rainfall
of significant tonight. Band of mid level clouds will track across
the area overnight but low levels look a bit too dry to support any
mention of rain overnight. A bit of a concern that some of the hi-
res model simulations suggest a band of showers developing this
evening, probably associated with the mid level clouds now over
western Iowa, and then tracks the rain east-southeast across parts
of the forecast area overnight. Other than an isolated report of
some light rain coming out of cloud decks of 10,000 feet or higher,
have not seen any persistent reports of rain coming out of the cloud
deck to our west. Based on the present movement of the weak echo
returns to our west, will include the chance for light rain/sprinkles
this evening across the west.
Front should settle over the Ohio Valley on sunday with another fast
moving wave embedded in the northwest flow aloft. A little better
lift associated with this feature on Sunday with models also showing
some fairly decent isent ascent and lowering pressure deficits across
our area, especially across our north where POPs will be in the 25-35
percent range into the afternoon hours. Models still depicting some
isent ascent Sunday evening north of the surface boundary before
weakening overnight. Most of the lift associated with the upper wave
should be to our east by mid afternoon or early evening so will keep
the low POPs going untii mid-afternoon until the threat shifts off
to our east. Once the wave shifts away from the area Sunday night
into Monday, the front will get a shove further to the south during
the day Monday as high pressure builds over the Great Lakes with
upper level heights slowly building across the Midwest. This will
bring more seasonable temperatures to our area into Tuesday.
LONG TERM...Wednesday through Saturday
A more typical pattern for the second week of May as upper level
ridging builds across the southeast U.S. in response to a western
U.S. trof that will shift slowly east bringing above normal temps
and increasing chances for showers and thunderstorms, especially
Thursday night and Friday. The frontal boundary that was lying well
to our south early in the week, should shift north as a warm front
late Tuesday night and be north of our area by Wednesday evening
with the main focus for showers and thunderstorms along and to the
north of the warm front, and along the eastward advancing cold
front, well out to our west thru Thursday. As the main upper level
energy swings northeast out of the southern Plains late Thursday,
we should start to see an increasing threat for showers and storms
in our area Thursday night, especially across the west, and over
the entire area on Friday. As the warm front lifts north across
the area late Tuesday night into Wednesday morning, we will
continue to include some low chance POPs north but models continue
to trend further north with the better rain chances as the front
retreats north.
Based on the 12z timing off the ECMWF, cold frontal passage looks
to occur in our area on Friday with the better rain chances shifting
east and southeast as the cold front and Pacific air mass tracks
across the Midwest.
Smith
&&
.AVIATION...
ISSUED 1251 PM CDT Sat May 3 2014
VFR conditions will prevail through the entire 18z TAF period. A
weak upper-level disturbance will spread mid-level clouds across
the area by late this afternoon through the evening hours. NAM
forecast soundings show 12000ft ceilings arriving at KPIA by
around 22z, spreading eastward to KCMI by 00z. While some high-res
models such as the HRRR suggest the potential for a few light
showers/sprinkles, think airmass will remain too dry below 700mb
to support any precip. Will therefore keep forecast dry, with only
a mid-level overcast this evening. Clouds will clear from west to
east overnight. After that, another fast-moving wave will approach
from the northwest on Sunday. As has been the case with the past
several model runs, the best focus for lower clouds and showers
will remain north of the central Illinois terminals. Will bring
mid-clouds back to the I-74 TAF sites Sunday morning, with mostly
clear skies persisting further south at both KSPI and KDEC. Gusty
W/NW winds this afternoon will decrease and eventually become NE
late tonight into Sunday after a frontal boundary passes through
the area.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
246 PM CDT SAT MAY 3 2014
.DISCUSSION...
324 AM...FORECAST CONCERNS INCLUDE SLIGHT CHANCE OF SHOWERS LATE
THIS AFTERNOON/EARLY EVENING...A PERIOD OF SHOWERS SUNDAY
MORNING...PATCHY FROST MONDAY MORNING...COOL/DRY EASTERLY FLOW
EARLY NEXT WEEK...THEN A SIGNIFICANT WARM UP WEDNESDAY/THURSDAY
ALONG WITH A CHANCE OF THUNDERSTORMS.
A FRONTAL BOUNDARY IS MOVING ACROSS THE AREA EARLY THIS MORNING.
NOT QUITE A COLD FRONT AS NO TEMP DROP...MORE OF A WIND SHIFT AND
SKIES ARE CLEARING WHICH WILL ALLOW FOR SUNSHINE THIS MORNING
WHICH WILL HELP PUSH TEMPS INTO THE 60S THIS AFTERNOON. ANOTHER
WEAK UPPER LEVEL WAVE WILL MOVE ACROSS THE WESTERN LAKES LATE THIS
AFTERNOON INTO THIS EVENING WITH INCREASING CLOUD COVER LATER THIS
AFTERNOON AND THERE IS A SMALL CHANCE OF A SHOWER OR SOME
SPRINKLES WITH THIS FEATURE. BEST TIMING WOULD LIKELY BE CLOSE TO
SUNSET/EARLY EVENING AND MAINLY ACROSS THE NORTHERN THIRD OF THE
AREA AND OPTED TO STAY DRY WITH THIS FORECAST...BUT IT WILL NEED
TO BE WATCHED THROUGH THE DAY.
A BIT STRONGER WAVE WILL ARRIVE ACROSS THE AREA SUNDAY MORNING AND
THE MODELS ARE IN GOOD AGREEMENT WITH A BAND OF SHOWERS DEVELOPING
SHORTLY AFTER SUNRISE THOUGH THE EXACT PLACEMENT/AXIS IS STILL
SHIFTING AND COULD BE SOMEWHAT NARROW...BUT WILL LIKELY BE
CENTERED ON THE LOT CWA. BUMPED POPS UP A BIT MORE AS WELL AS SKY
COVER BUT TRENDS OF THIS ACTIVITY SHIFTING SOUTHEAST AND WEAKENING
BY EARLY/MID AFTERNOON LOOK ON TRACK. AND AS A RESULT...WESTERN
AREAS WILL LIKELY SEE SOME SUN WITH TEMPS POSSIBLY REBOUNDING BACK
INTO THE LOWER 60S...THOUGH TEMPS WILL BE TRICKY ESPECIALLY
EASTERN AREAS WHERE PRECIP AND CLOUD COVER WILL LINGER LONGER.
AS THIS PRECIP SUNDAY IS ENDING...WINDS WILL BE SHIFTING NORTHEAST
AS HIGH PRESSURE BUILDS FROM THE UPPER MIDWEST SUNDAY TO THE
NORTHERN LAKES SUNDAY NIGHT AND MONDAY. COOLER AND DRIER AIR WILL
SPREAD ACROSS AT LEAST THE NORTHERN PORTIONS OF THE AREA SUNDAY
AFTERNOON INTO SUNDAY NIGHT. WHILE THE SETUP ISN/T PERFECT...WIND
SPEEDS MAY DROP OFF ENOUGH ACROSS THE NORTH SUNDAY NIGHT INTO
MONDAY MORNING COMBINED WITH AT LEAST PARTLY CLOUDY SKIES TO ALLOW
TEMPS TO DROP INTO THE MID/UPPER 30S. CONFIDENCE REGARDING HOW LOW
TEMPS MAY DROP IS FAIRLY LOW FROM THIS DISTANCE BUT THERE IS AT
LEAST A SMALL CHANCE OF PATCHY FROST ACROSS PARTS OF THE NORTHERN
CWA AWAY FROM URBAN AREAS. DUE TO THE UNCERTAINTY...WILL NOT BE
INCLUDING THAT MENTION IN ANY OTHER FORECASTS/PRODUCTS...BUT THIS
TIME PERIOD WILL NEED TO BE MONITORED FOR TEMP TRENDS.
ANOTHER WEAK WAVE WILL MOVE ACROSS THE REGION ON MONDAY BUT
CONFIDENCE HERE REMAINS VERY LOW FOR BOTH LOCATION AND TIMING AND
OPTED TO MAINTAIN SLIGHT CHANCE POPS FOR NOW FOR MONDAY AFTERNOON
BUT ANYTHING THAT DOES DEVELOP SHOULD BE BRIEF/LIGHT.
EASTERLY FLOW BECOMES PREVAILING MONDAY INTO TUESDAY AND WITH THE
LARGE HIGH SLOWLY SHIFTING EAST ACROSS THE NORTHERN LAKES...
SUSPECT THERE WILL BE SOME RATHER LOW DEWPOINTS ADVECTING WEST
TOWARD THE AREA AND LOWERED DEWPOINTS SEVERAL DEGREES BOTH DAYS.
HIGHS EACH DAY WILL BE A BIT TRICKY. THERMALLY...TUESDAY COULD BE
MUCH WARMER THAN MONDAY BUT EASTERLY FLOW REMAINS THOUGH THE
DRIER AIR WILL BE EASIER TO WARM WITH SUNSHINE. SO HAVE KEPT HIGHS
FROM THE UPPER 50S NORTHEAST IL TO MID 60S SOUTH ON MONDAY BUT
WARMED TEMPS 6 TO 10 DEGREES FOR HIGHS ON TUESDAY...WHICH MAY
STILL BE TOO COOL. IMMEDIATE LAKE SHORE AREAS WILL REMAIN MUCH
COOLER.
WITH A LARGE TROUGH DIGGING ACROSS THE WESTERN U.S...A RIDGE WILL
BUILD ACROSS THE PLAINS AND SHIFT EAST ACROSS THE LAKES REGION
WEDNESDAY INTO THURSDAY. THE 00Z GEM/GFS/ECMWF ALL SEEM TO HAVE A
GENERALLY SIMILAR SOLUTION WITH POSSIBLE CONVECTION LATE TUESDAY
NIGHT INTO WEDNESDAY AS THE RIDGE IS BUILDING NORTH...THEN MAINLY
DRY CONDITIONS WEDNESDAY NIGHT AND THURSDAY WITH THE WARM FRONT
WELL NORTH OF THE AREA WITH AN UNSETTLED PATTERN THURSDAY NIGHT
INTO FRIDAY AS THE COLD FRONT PUSHES ACROSS THE AREA. ITS A BIT
EARLY TO PIN DOWN ANY SEVERE THREATS WITH THIS PATTERN BUT THE
BEST CHANCE WOULD MOST LIKELY BE WITH THE COLD FRONT...WITH THAT
TIMING STILL UNCERTAIN FROM THIS DISTANCE.
AS FOR HIGHS...STILL SOMEWHAT CONCERNED THAT ANY CONVECTION ON
WEDNESDAY MORNING COULD INHIBIT THE NORTHWARD PROGRESS OF THE
WARM FRONT AND HAVE A BIG IMPACT ON HIGHS ACROSS THE NORTH AND
THUS WITH SOUTHEASTERLY FLOW...IL LAKESHORE WILL BE SIGNIFICANTLY
COOLER BUT EXPECT MID 70S FROM A RFD/DPA/GYY LINE SOUTH WITH AREAS
ACROSS CENTRAL IL LIKELY TO REACH THE LOWER 80S. WITH THE ENTIRE
AREA EXPECTED TO BE WELL IN THE WARM SECTOR ON THURSDAY....HAVE
NUDGED TEMPS UP TO AROUND 80/LOWER 80S EVERYWHERE. LATEST ECMWF
AND GEM TEMPS WOULD SUGGEST THAT THESE VALUES COULD STILL BE A
FEW DEGREES TOO COOL. THURSDAY LIKELY TO BE A RATHER WINDY DAY AS
WELL. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* GUSTY WEST-NORTHWEST WINDS 25-30 KT THIS AFTN.
* NORTH WINDS 10-15 KT EARLY SUNDAY BECOMING NORTHEAST IN THE
AFTERNOON.
* PERIOD OF SHRA POSSIBLE LATE SUNDAY MORNING/EARLY
AFTERNOON...BUT WITH CIGS/VIS EXPECTED TO REMAIN VFR.
RATZER
//DISCUSSION...UPDATED 18Z...
GUSTY WEST-NORTHWEST WINDS EXPECTED TO CONTINUE THROUGH THIS
AFTERNOON AS A COMBINATION OF FAIRLY DEEP MIXED LAYER AND LOCATION
OF TERMINALS ALONG SOUTHERN PERIPHERY OF FAIRLY STRONG MID/UPPER
LEVEL JET. GRADIENT IS EXPECTED TO SLOWLY WEAKEN LATE THIS
AFTERNOON AND MORE QUICKLY THIS EVENING AS WEAK SURFACE HIGH
PRESSURE RIDGE SPREADS INTO THE AREA TONIGHT. WINDS/GUSTS EXPECTED
TO DIMINISH QUICKLY WITH SUNSET. WEAK COLD FRONT ASSOCIATED WITH
SHEARED WAVE PASSING WELL NORTH OF THE REGION THEN SAGS ACROSS THE
AREA DURING THE PRE-DAWN HOURS...RESULTING IN WIND SHIFT TO NORTH-
NORTHWEST BY MORNING INITIALLY IN THE 10-15 KT RANGE. SURFACE RIDGE
THEN BUILDS BACK INTO AREA BEHIND DEPARTING COLD FRONT...ALLOWING
WINDS TO VEER NORTHEAST BY EARLY AFTERNOON AND LIKELY MORE
EASTERLY BY SUNDAY EVENING.
ASIDE FROM WINDS...DIURNAL SCT-BKN CU WITH BASES AROUND 6000 FT
BEGINNING TO DEVELOP PER VISIBLE SAT IMAGERY THIS AFTERNOON. MORE
PREVALENT 6000-8000 FT DECK EXPECTED TO DEVELOP/EXPAND ACROSS AREA
TONIGHT INTO SUNDAY MORNING WITH WARM ADVECTION DEVELOPING ALOFT.
VARIOUS MODELS CONTINUE TO INDICATE FAIRLY HIGH POTENTIAL FOR
SHOWERS TO DEVELOP SUNDAY MORNING/MIDDAY...WITH BANDED COVERAGE
PATTERN ALONG THE NORTHWEST-SOUTHEAST THERMAL GRADIENT. BANDS
LIKELY TO BE SOMEWHAT NARROW...SO WHILE CONFIDENCE THAT SHOWERS
WILL OCCUR IS HIGH...IT IS SOMEWHAT LOWER WITH RESPECT TO TIMING
AND COVERAGE AT INDIVIDUAL POINT TERMINALS. LOW LEVELS REMAIN
RELATIVELY DRY AND CEILINGS/VIS EXPECTED TO REMAIN PRIMARILY VFR.
SHOWER THREAT DIMINISHES IN THE AFTERNOON.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN SHRA COVERAGE/EXACT TIMING AND TIMING OF
SHIFT FROM NORTH TO NORTHEAST WINDS SUNDAY.
* HIGH CONFIDENCE ALL OTHER ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...SLGT CHC FOR SHRA DURING THE AFTERNOON.
TUESDAY...CHC FOR TSRA DURING THE NIGHT.
WEDNESDAY THROUGH FRIDAY...CHC FOR TSRA.
BEACHLER
&&
.MARINE...
245 PM CDT
MODERATE WESTERLY WINDS TO AROUND 30 KT HAVE DEVELOPED ACROSS
PORTIONS OF THE UPPER MIDWEST AND GREAT LAKES THIS AFTERNOON IN THE
WAKE OF A COLD FRONT. STILL THE MARINE LAYER REMAINS FAIRLY STABLE
ACROSS LAKE MICHIGAN WHICH IS KEEPING WINDS LIGHTER AS YOU HEAD EAST
ACROSS THE LAKE. A SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH
THIS EVENING FOR THE ILLINOIS NEARSHORE WATERS. WINDS SHOULD SLOWLY
TRENDS DOWN OVERNIGHT INTO SUNDAY AS HIGH PRESSURE BUILDS ACROSS THE
AREA. BY MONDAY...EXPECT LOW PRESSURE TO START TAKING SHAPE OVER THE
CENTRAL PLAINS WHICH WILL RESULT IN NORTHEAST FLOW FRESHENING UP
ACROSS LAKE MICHIGAN. THE LOW WILL FINALLY LIFT NORTHEAST INTO THE
UPPER MIDWEST LATE IN THE WEEK WITH WINDS VEERING TO THE SOUTHEAST
AS THIS OCCURS.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 9 PM
SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1251 PM CDT Sat May 3 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sat May 3 2014
Weak cold front has dropped south of the I-70 corridor this
morning, pushing its associated mid-level cloud cover into the
Ohio River Valley. Further north, mostly sunny skies prevail
across central Illinois. 15z/10am temps are in the upper 50s and
lower 60s, well on their way to afternoon highs in the lower 70s.
Current forecast has a good handle on things, so no update is
needed at this time.
Barnes
&&
.AVIATION...
ISSUED 1251 PM CDT Sat May 3 2014
VFR conditions will prevail through the entire 18z TAF period. A
weak upper-level disturbance will spread mid-level clouds across
the area by late this afternoon through the evening hours. NAM
forecast soundings show 12000ft ceilings arriving at KPIA by
around 22z, spreading eastward to KCMI by 00z. While some high-res
models such as the HRRR suggest the potential for a few light
showers/sprinkles, think airmass will remain too dry below 700mb
to support any precip. Will therefore keep forecast dry, with only
a mid-level overcast this evening. Clouds will clear from west to
east overnight. After that, another fast-moving wave will approach
from the northwest on Sunday. As has been the case with the past
several model runs, the best focus for lower clouds and showers
will remain north of the central Illinois terminals. Will bring
mid-clouds back to the I-74 TAF sites Sunday morning, with mostly
clear skies persisting further south at both KSPI and KDEC. Gusty
W/NW winds this afternoon will decrease and eventually become NE
late tonight into Sunday after a frontal boundary passes through
the area.
Barnes
&&
.PREV DISCUSSION...
ISSUED 304 AM CDT Sat May 3 2014
A transition in our upper level pattern will occur in the next
24-48 hours as we go from a persistent northwest flow to more of a
zonal flow early next week. An upper trough digging into the
western states will allow ridging to build by midweek, along with
much warmer temperatures. Eventually the western trough will shift
east toward the Mississippi valley later in the week, resulting in
precipitation and a return to cooler temperatures.
SHORT TERM...Today through Monday
Low pressure in southeast WI will shift toward eastern Ontario by
this evening. A weak cold front, just west of the IL River valley
early this morning, will settle into central and southeast IL
today. The lack of moisture and forcing with this feature will
just result in a few clouds. The upstream low level temperature
fields are not too much different behind this weak front, and in
fact are even a bit warmer than yesterday. Thus, with more
sunshine anticipated, highs today should be nearly 10 degrees
warmer, around 70.
Upper level support rapidly shearing toward northern IL from the
WNW Sunday morning will produce a quick shot of light rainfall
along and north of the I-74 corridor. This fast moving system will
exit the region by Sunday afternoon, leaving some cloudiness
behind, which will keep temperatures down in the lower to middle
60s. The rest of central and SE IL can expect mostly sunny
conditions with highs once again near 70.
Another quick moving upper level system moving through the nearly
zonal flow could bring a few showers to northern IL Monday
afternoon. For now will stick with a slight chance of showers in
the areas mainly north of I-74 since the moisture starved system
will have a better chance of squeezing out light showers farther
north. Once again the presence of some clouds and a E-NE surface
wind will keep temperatures in the mid to upper 60s north, with 70
to 75 in the central and southeast parts of the forecast area.
LONG TERM...Tuesday through Friday
A nearly stationary front near the Ohio valley Tuesday will keep
temperatures seasonable in the lower to middle 70s. By Tuesday
night the models are in good agreement that a building upper level
ridge will allow the front to quickly lift north/reform as a warm
front. Once again the I-74 corridor will be the most likely
location for scattered showers/t-storms Tuesday night as moisture
is projected to focus on the boundary.
The whole forecast area will likely be in the warm sector
Wednesday where temperatures will climb well into the 80s. A few
t-storms could develop with the increasing low level moisture, but
for now will keep the PoPs in the slight chance category due to a
lack of a focusing mechanism.
The better chances for showers and t-storms can be expected
Thursday west of I-55 and across the whole forecast area by
Friday along and ahead of a relatively slow moving cold front. The
GFS and European are actually in fairly good agreement as to the
movement of the front and the potential for rainfall from late
Thursday through Friday. Temperatures will continue to be warm on
Thursday, but due to the presence of clouds and potential for
rainfall, readings Friday should be nearly 10 degrees cooler.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
549 PM CDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 543 PM CDT SAT MAY 3 2014
BASED ON RADAR AND OBS I HAVE UPDATED FORECAST TO RAISE POPS ACROSS
W/SW PORTIONS OF CWA INTO EARLY EVE FOR BAND OF SHOWERS ATTENDANT
TO MID LEVEL FRONTOGENETICAL FORCING. WITH CONSIDERABLE T/TD
SPREADS NOT EXPECTING MUCH MORE THAN A COUPLE HUNDREDTHS OF AN
INCH.
&&
.SYNOPSIS...
ISSUED AT 312 PM CDT SAT MAY 3 2014
SPRAWLING LOW PRESSURE OVER HUDSON BAY WAS PROVIDING THE MID
MISSISSIPPI VALLEY WITH A BREEZY AND RELATIVELY MILD SATURDAY. FOR
THE MOST PART THE REGION WAS DRY WITH THE EXCEPTION OF A NARROW
BAND OF RAIN FROM SOUTHEAST SOUTH DAKOTA INTO SOUTH CENTRAL IOWA.
THE RAIN WAS COMING FROM A MID CLOUD DECK WITH A DEEP AND DRY SUB
CLOUD LAYER WHICH WAS CAUSING MOST OF THE RAIN TO EVAPORATE BEFORE
REACHING THE GROUND. THE RAIN AND MID CLOUDS WERE OCCURRING IN A
REGION OF MID LEVEL FGEN ON THE SOUTHWEST FLANK OF A 120KT H3 JET
STREAK OVER THE NORTH CENTRAL U.S.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 312 PM CDT SAT MAY 3 2014
THE REGION WILL REMAIN IN NORTHWEST FLOW THROUGH SUNDAY AS AN UPPER
RIDGE MOVES INTO THE HIGH PLAINS AND AN UPPER LOW OVER ONTARIO
WEAKENS. AS THE UPPER RIDGE MOVES EAST...SURFACE HIGH PRESSURE
WILL BUILD INTO THE WESTERN GREAT LAKES WHILE A WARM FRONT SETS UP
FROM CENTRAL PLAINS INTO THE LOWER OHIO VALLEY.
THE FIRST CONCERN WILL BE THE HIGH BASED RAIN OVER THE WESTERN
HALF OF IOWA. THE HRRR HAS BEEN CONSISTENT IN BRINGING THE RAIN
ACROSS THE DVN CWFA LATE THIS AFTERNOON AND EARLY THIS EVENING.
HOWEVER THE HRRR HAS ALSO BEEN CONSISTENTLY TO FAR NORTHEAST WITH
THE PRECIPITATION. ALSO THE RAIN SEEMS TO CORRELATE WELL WITH FGEN
IN THE 700-500MB LAYER WHICH THE RAP SHOWS WEAKENING WITH TIME.
FOR NOW WILL GO WITH SOME SPRINKLES IN THE SOUTH THIS EVENING...THINKING
THAT MOST OF THE PRECIPITATION WILL DISSIPATE BEFORE REACHING THE
GROUND. LATER TONIGHT AND SUNDAY MORNING MODELS SHOW THE RIGHT
ENTRANCE REGION OF THE NORTH CENTRAL U.S. H3 JET MOVING THROUGH
THE REGION. MID/LOW LEVEL FGEN AND UPPER DIVERGENCE ASSOCIATED
WITH THE JET ARE PROGGED TO SUPPORT ANOTHER BAND OF RAIN THAT SHOULD
IMPACT AREAS MAINLY NORTH OF I80 SUNDAY MORNING. GIVEN THE
CONSISTENCY BETWEEN THE MODELS WITH THIS FEATURE...HAVE INCREASED
POPS TO LIKELY FOR AREAS MAINLY NORTH OF HIGHWAY 30. THE RAIN
SHOULD BE EAST OF THE FORECAST AREA BY EARLY AFTERNOON WITH DRY
WEATHER EXPECTED THE REST OF THE DAY.
WITH INCREASING MID CLOUDS OVERNIGHT TONIGHT TEMPERATURES WERE
KEPT ON THE MILDER SIDE OF GUIDANCE MAINLY IN THE 40S. SUNDAY WITH
THE SURFACE HIGH SETTING UP TO OUR NORTH AND THE DEVELOPING WARM
FRONT SOUTH...A DECENT THERMAL GRADIENT WILL DEVELOP ACROSS THE
REGION. HIGHS SHOULD RANGE FROM NEAR 70 IN THE FAR SOUTH TO THE
MIDDLE 50S NORTH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 312 PM CDT SAT MAY 3 2014
FORECAST FOCUS IS ON WELCOMED WARMING TREND NEXT WEEK AND ON PCPN
CHANCES MID TO LATE WEEK.
SUNDAY NIGHT...WEAK DISTURBANCE TO HAVE EXITED THE AREA WITH HIGH
PRESSURE BUILDING INTO THE GREAT LAKES REGION. WITH A STATIONARY
BOUNDARY WELL TO OUR SOUTH AND EASTERLY FLOW OFF THE GREAT LAKES...
WILL SEE TEMPS DROP INTO THE UPPER 30S/LOW 40S UNDER PARTLY CLOUDY
SKIES.
MONDAY-TUESDAY...EASTERLY LOW LEVEL FLOW AND SOME MID-HIGH LEVEL
CLOUDS WILL BE THE NORM AS HIGH PRESSURE DRIFTS OVER THE GREAT LAKES
AND A FRONTAL BOUNDARY REMAINS SOUTH OF THE AREA DRAPED OVER
MISSOURI AND SOUTHERN ILLINOIS. HIGHS WILL REACH THE LOWER 60S NORTH
TO LOWER 70S IN THE FAR SOUTH WHICH IS NEAR NORMAL FOR EARLY MAY.
TUESDAY NIGHT-WEDNESDAY...WARM FRONT PROGGED TO LIFT NORTH INTO
NORTHEAST IOWA AND SOUTHERN WISCONSIN BY EARLY EVENING WEDNESDAY.
CONVERGENCE ALONG THE FRONT COUPLED WITH A 40KT LLJ SHOULD ALLOW FOR
SOME OVERNIGHT ELEVATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY ACROSS
THE NORTHERN HALF OF THE CWA. MUCAPES BETWEEN 1500-2000 J/KG AND
PROGGED 40KT 0-6KM SHEAR VALUES SUGGEST SMALL SEVERE THREAT WITH ANY
STRONG STORM THAT WOULD DEVELOP TO PRODUCE MARGINAL SEVERE HAIL.
OVERNIGHT LOW TEMPERATURES WILL DEPEND LARGELY ON SPEED OF WARM
FRONT LIFTING NORTH. FOR NOW WILL GO WITH LOWER 50S NORTH TO THE
LOWER 60S SOUTH. CWA TO BE COMPLETELY IN THE WARM SECTOR BY
WEDNESDAY AFTERNOON WITH TEMPERATURES SOARING INTO THE UPPER
70S/MIDDLE 80S AND A STRONG CAP IN PLACE OVER THE AREA. IT WILL ALSO
FEEL HUMID...WITH DEWPOINTS IN THE UPPER 50S AND LOWER 60S.
WEDNESDAY NIGHT...STRONG LLJ TO ONCE AGAIN DEVELOP OVERNIGHT OVER
THE PLAINS WITH STORMS DEVELOPING ON THE NOSE OF JET ACROSS CENTRAL
IOWA. LATEST MODELS TRACK THESE STORMS EAST AND WEAKEN AS THEY NEAR
THE CWA. NONETHELESS HAVE MAINTAINED HIGH CHANCE POPS ACROSS THE
WEST FOR THIS BUT MAY NEED TO BE LOWERED IF MODELS CONTINUE TO SHOW
WEAKER FORCING. STEEP MID LEVEL LAPSE RATES ALSO SUGGEST A FEW RUMBLES OF
THUNDER WILL BE POSSIBLE AS WELL. TEMPERATURES WILL BE VERY MILD
WEDNESDAY NIGHT DUE TO REGION IN THE WARM SECTOR WITH LOWS ONLY DROPPING
INTO THE LOWER 60S.
THURSDAY...WARM AND HUMID CONDITIONS WILL BE COMMON AS STRONG
SOUTHERLY FLOW CONTINUES AHEAD OF SURFACE LOW IN THE PLAINS. LATEST
12Z MODEL SUITE HAS SLOWED THE PROGRESSION OF THE COLD FRONT SOME
WITH IT NOT ARRIVING INTO THE WESTERN PART OF THE CWA UNTIL EARLY
FRIDAY. THIS SLOWER FRONT WILL HELP BOOST TEMPERATURES AND HAVE
RAISED READINGS A FEW DEGREES WITH FORECAST HIGHS SIMILAR TO
WEDNESDAY. STRONG DAYTIME HEATING WILL DESTABILIZE THE ATMOSPHERE
DURING THE DAY AND COMBINED WITH A FAVORABLE JET AXIS/STRONG SHEAR
PROFILE SUGGESTS STRONG TO SEVERE STORMS WILL BE POSSIBLE DURING THE
LATE AFTERNOON AND EVENING HOURS. SPC CURRENTLY HAS THE AREA
OUTLINED FOR THIS IN ITS DAY 4-8 OUTLOOK AND WILL CONTINUE TO
MONITOR CLOSELY THIS TIME FRAME BY LATER SHIFTS.
REST OF EXTENDED...COLD FRONT TO PUSH THROUGH THE AREA FRIDAY
MORNING WITH CLEARING SKIES AND MORE COMFORTABLE CONDITIONS AS DEW
POINTS DROP INTO THE LOWER 50S. DRY CONDITIONS AND SEASONABLE
TEMPERATURES WILL END THE WORK WEEK WITH HIGHS IN THE UPPER 60S/LOW
70S AND LOWS IN THE UPPER 40S/LOWER 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1225 PM CDT SAT MAY 3 2014
HIGH PRESSURE BUILDING FROM THE NORTHERN PLAINS INTO THE WESTERN
GREAT LAKES BY SUNDAY AFTERNOON WILL TURN SURFACE WINDS TO THE
NORTH TONIGHT AND NORTHEAST SUNDAY MORNING. VFR FLIGHT CONDITIONS
ARE EXPECTED THROUGH MID DAY SUNDAY DESPITE A COUPLE OF WEAK
SYSTEMS MOVING THROUGH. THE FIRST IS CURRENTLY OVER EASTERN
NEBRASKA AND SOUTH DAKOTA AND WAS PRODUCING SOME LIGHT RAIN. THIS
FEATURE MAY BRUSH SOUTHEAST IOWA AND NORTHEAST MISSOURI LATE THIS
AFTERNOON AND COULD CAUSE A FEW SPRINKLES. CEILINGS THOUGH SHOULD
REMAIN NEAR OR ABOVE 8KFT. ANOTHER DISTURBANCE WILL MOVE THROUGH
SUNDAY MORNING BRINGING SOME LIGHT RAIN TO PARTS OF EASTERN IOWA
AND NORTHERN IL. AGAIN CIGS AND VSBYS WITH THIS FEATURE SHOULD
REMAIN VFR.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...05
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...GROSS
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
312 PM CDT SAT MAY 3 2014
.SYNOPSIS...
ISSUED AT 312 PM CDT SAT MAY 3 2014
SPRAWLING LOW PRESSURE OVER HUDSON BAY WAS PROVIDING THE MID
MISSISSIPPI VALLEY WITH A BREEZY AND RELATIVELY MILD SATURDAY. FOR
THE MOST PART THE REGION WAS DRY WITH THE EXCEPTION OF A NARROW
BAND OF RAIN FROM SOUTHEAST SOUTH DAKOTA INTO SOUTH CENTRAL IOWA.
THE RAIN WAS COMING FROM A MID CLOUD DECK WITH A DEEP AND DRY SUB
CLOUD LAYER WHICH WAS CAUSING MOST OF THE RAIN TO EVAPORATE BEFORE
REACHING THE GROUND. THE RAIN AND MID CLOUDS WERE OCCURRING IN A
REGION OF MID LEVEL FGEN ON THE SOUTHWEST FLANK OF A 120KT H3 JET
STREAK OVER THE NORTH CENTRAL U.S.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 312 PM CDT SAT MAY 3 2014
THE REGION WILL REMAIN IN NORTHWEST FLOW THROUGH SUNDAY AS AN UPPER
RIDGE MOVES INTO THE HIGH PLAINS AND AN UPPER LOW OVER ONTARIO
WEAKENS. AS THE UPPER RIDGE MOVES EAST...SURFACE HIGH PRESSURE
WILL BUILD INTO THE WESTERN GREAT LAKES WHILE A WARM FRONT SETS UP
FROM CENTRAL PLAINS INTO THE LOWER OHIO VALLEY.
THE FIRST CONCERN WILL BE THE HIGH BASED RAIN OVER THE WESTERN
HALF OF IOWA. THE HRRR HAS BEEN CONSISTENT IN BRINGING THE RAIN
ACROSS THE DVN CWFA LATE THIS AFTERNOON AND EARLY THIS EVENING.
HOWEVER THE HRRR HAS ALSO BEEN CONSISTENTLY TO FAR NORTHEAST WITH
THE PRECIPITATION. ALSO THE RAIN SEEMS TO CORRELATE WELL WITH FGEN
IN THE 700-500MB LAYER WHICH THE RAP SHOWS WEAKENING WITH TIME.
FOR NOW WILL GO WITH SOME SPRINKLES IN THE SOUTH THIS EVENING...THINKING
THAT MOST OF THE PRECIPITATION WILL DISSIPATE BEFORE REACHING THE
GROUND. LATER TONIGHT AND SUNDAY MORNING MODELS SHOW THE RIGHT
ENTRANCE REGION OF THE NORTH CENTRAL U.S. H3 JET MOVING THROUGH
THE REGION. MID/LOW LEVEL FGEN AND UPPER DIVERGENCE ASSOCIATED
WITH THE JET ARE PROGGED TO SUPPORT ANOTHER BAND OF RAIN THAT SHOULD
IMPACT AREAS MAINLY NORTH OF I80 SUNDAY MORNING. GIVEN THE
CONSISTENCY BETWEEN THE MODELS WITH THIS FEATURE...HAVE INCREASED
POPS TO LIKELY FOR AREAS MAINLY NORTH OF HIGHWAY 30. THE RAIN
SHOULD BE EAST OF THE FORECAST AREA BY EARLY AFTERNOON WITH DRY
WEATHER EXPECTED THE REST OF THE DAY.
WITH INCREASING MID CLOUDS OVERNIGHT TONIGHT TEMPERATURES WERE
KEPT ON THE MILDER SIDE OF GUIDANCE MAINLY IN THE 40S. SUNDAY WITH
THE SURFACE HIGH SETTING UP TO OUR NORTH AND THE DEVELOPING WARM
FRONT SOUTH...A DECENT THERMAL GRADIENT WILL DEVELOP ACROSS THE
REGION. HIGHS SHOULD RANGE FROM NEAR 70 IN THE FAR SOUTH TO THE
MIDDLE 50S NORTH.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 312 PM CDT SAT MAY 3 2014
FORECAST FOCUS IS ON WELCOMED WARMING TREND NEXT WEEK AND ON PCPN
CHANCES MID TO LATE WEEK.
SUNDAY NIGHT...WEAK DISTURBANCE TO HAVE EXITED THE AREA WITH HIGH
PRESSURE BUILDING INTO THE GREAT LAKES REGION. WITH A STATIONARY
BOUNDARY WELL TO OUR SOUTH AND EASTERLY FLOW OFF THE GREAT LAKES...
WILL SEE TEMPS DROP INTO THE UPPER 30S/LOW 40S UNDER PARTLY CLOUDY
SKIES.
MONDAY-TUESDAY...EASTERLY LOW LEVEL FLOW AND SOME MID-HIGH LEVEL
CLOUDS WILL BE THE NORM AS HIGH PRESSURE DRIFTS OVER THE GREAT LAKES
AND A FRONTAL BOUNDARY REMAINS SOUTH OF THE AREA DRAPED OVER
MISSOURI AND SOUTHERN ILLINOIS. HIGHS WILL REACH THE LOWER 60S NORTH
TO LOWER 70S IN THE FAR SOUTH WHICH IS NEAR NORMAL FOR EARLY MAY.
TUESDAY NIGHT-WEDNESDAY...WARM FRONT PROGGED TO LIFT NORTH INTO
NORTHEAST IOWA AND SOUTHERN WISCONSIN BY EARLY EVENING WEDNESDAY.
CONVERGENCE ALONG THE FRONT COUPLED WITH A 40KT LLJ SHOULD ALLOW FOR
SOME OVERNIGHT ELEVATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY ACROSS
THE NORTHERN HALF OF THE CWA. MUCAPES BETWEEN 1500-2000 J/KG AND
PROGGED 40KT 0-6KM SHEAR VALUES SUGGEST SMALL SEVERE THREAT WITH ANY
STRONG STORM THAT WOULD DEVELOP TO PRODUCE MARGINAL SEVERE HAIL.
OVERNIGHT LOW TEMPERATURES WILL DEPEND LARGELY ON SPEED OF WARM
FRONT LIFTING NORTH. FOR NOW WILL GO WITH LOWER 50S NORTH TO THE
LOWER 60S SOUTH. CWA TO BE COMPLETELY IN THE WARM SECTOR BY
WEDNESDAY AFTERNOON WITH TEMPERATURES SOARING INTO THE UPPER
70S/MIDDLE 80S AND A STRONG CAP IN PLACE OVER THE AREA. IT WILL ALSO
FEEL HUMID...WITH DEWPOINTS IN THE UPPER 50S AND LOWER 60S.
WEDNESDAY NIGHT...STRONG LLJ TO ONCE AGAIN DEVELOP OVERNIGHT OVER
THE PLAINS WITH STORMS DEVELOPING ON THE NOSE OF JET ACROSS CENTRAL
IOWA. LATEST MODELS TRACK THESE STORMS EAST AND WEAKEN AS THEY NEAR
THE CWA. NONETHELESS HAVE MAINTAINED HIGH CHANCE POPS ACROSS THE
WEST FOR THIS BUT MAY NEED TO BE LOWERED IF MODELS CONTINUE TO SHOW
WEAKER FORCING. STEEP MID LEVEL LAPSE RATES ALSO SUGGEST A FEW RUMBLES OF
THUNDER WILL BE POSSIBLE AS WELL. TEMPERATURES WILL BE VERY MILD
WEDNESDAY NIGHT DUE TO REGION IN THE WARM SECTOR WITH LOWS ONLY DROPPING
INTO THE LOWER 60S.
THURSDAY...WARM AND HUMID CONDITIONS WILL BE COMMON AS STRONG
SOUTHERLY FLOW CONTINUES AHEAD OF SURFACE LOW IN THE PLAINS. LATEST
12Z MODEL SUITE HAS SLOWED THE PROGRESSION OF THE COLD FRONT SOME
WITH IT NOT ARRIVING INTO THE WESTERN PART OF THE CWA UNTIL EARLY
FRIDAY. THIS SLOWER FRONT WILL HELP BOOST TEMPERATURES AND HAVE
RAISED READINGS A FEW DEGREES WITH FORECAST HIGHS SIMILAR TO
WEDNESDAY. STRONG DAYTIME HEATING WILL DESTABILIZE THE ATMOSPHERE
DURING THE DAY AND COMBINED WITH A FAVORABLE JET AXIS/STRONG SHEAR
PROFILE SUGGESTS STRONG TO SEVERE STORMS WILL BE POSSIBLE DURING THE
LATE AFTERNOON AND EVENING HOURS. SPC CURRENTLY HAS THE AREA
OUTLINED FOR THIS IN ITS DAY 4-8 OUTLOOK AND WILL CONTINUE TO
MONITOR CLOSELY THIS TIME FRAME BY LATER SHIFTS.
REST OF EXTENDED...COLD FRONT TO PUSH THROUGH THE AREA FRIDAY
MORNING WITH CLEARING SKIES AND MORE COMFORTABLE CONDITIONS AS DEW
POINTS DROP INTO THE LOWER 50S. DRY CONDITIONS AND SEASONABLE
TEMPERATURES WILL END THE WORK WEEK WITH HIGHS IN THE UPPER 60S/LOW
70S AND LOWS IN THE UPPER 40S/LOWER 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1225 PM CDT SAT MAY 3 2014
HIGH PRESSURE BUILDING FROM THE NORTHERN PLAINS INTO THE WESTERN
GREAT LAKES BY SUNDAY AFTERNOON WILL TURN SURFACE WINDS TO THE
NORTH TONIGHT AND NORTHEAST SUNDAY MORNING. VFR FLIGHT CONDITIONS
ARE EXPECTED THROUGH MID DAY SUNDAY DESPITE A COUPLE OF WEAK
SYSTEMS MOVING THROUGH. THE FIRST IS CURRENTLY OVER EASTERN
NEBRASKA AND SOUTH DAKOTA AND WAS PRODUCING SOME LIGHT RAIN. THIS
FEATURE MAY BRUSH SOUTHEAST IOWA AND NORTHEAST MISSOURI LATE THIS
AFTERNOON AND COULD CAUSE A FEW SPRINKLES. CEILINGS THOUGH SHOULD
REMAIN NEAR OR ABOVE 8KFT. ANOTHER DISTURBANCE WILL MOVE THROUGH
SUNDAY MORNING BRINGING SOME LIGHT RAIN TO PARTS OF EASTERN IOWA
AND NORTHERN IL. AGAIN CIGS AND VSBYS WITH THIS FEATURE SHOULD
REMAIN VFR.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...DLF
SHORT TERM...DLF
LONG TERM...GROSS
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1233 PM CDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 1035 AM CDT SAT MAY 3 2014
UPDATE WAS JUST SENT TO LOWER THIS AFTERNOONS MAX TEMPS NORTH A
DEGREE OR TWO. USING A MIXING DEPTH OF 800MB...SIMILAR TO
YESTERDAY...YIELDS SLIGHT LOWER MAX TEMPS THAN CURRENT FORECAST
SUGGESTS. ALSO OF SOME CONCERN IS THE MID LEVEL CLOUDS MOVING
SOUTHEAST THROUGH THE DAKOTAS...SOUTH OF AN H3 JET AXIS FROM NORTH
DAKOTA INTO MINNESOTA. TIGHTENING MID LEVEL BAROCLINIC ZONE
SOUTHWEST OF THE AXIS SUPPORTS THE MID DECK EXPANDING FURTHER
SOUTHEAST. LATEST RAP DATA THOUGH...KEEPS THE CLOUDS NORTHWEST OF
THE CWFA THROUGH 21Z. IF THIS TIMING VERIFIES THEN THE CLOUDS WILL
NOT HAVE A SIGNIFICANT IMPACT ON AFTERNOON TEMPERATURES.
&&
.SYNOPSIS...
ISSUED AT 310 AM CDT SAT MAY 3 2014
OTHER THAN SOME PATCHY THIN CIRRUS SKIES WERE CLEAR ACROSS THE
DVN CWA WITH WEST WINDS ABOUT 10 MPH OR LESS. 3 AM TEMPERATURES
WERE IN THE 40S TO AROUND 50.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CDT SAT MAY 3 2014
FORECAST FOCUS ON A PLEASANT DAY AHEAD THEN A SMALL CHANCE OF
SHOWERS LATE TONIGHT IN OUR NW CWA.
TODAY...AFTER HAVING SEVERAL DAYS OF WELL BELOW NORMAL TEMPERATURES
WE WILL REVERSE THAT TREND TODAY. WITH A WEAK RIDGE OF HIGH PRESSURE
PASSING TO OUR SOUTH THERE SHOULD BE MUCH MORE SUNSHINE COMPARED
TO THE PAST SEVERAL DAYS. WITH THE STRONG MAY SUN AND WEST WINDS
AFTERNOON TEMPERATURES SHOULD RISE WELL INTO THE 60S TO LOWER 70S.
THESE READINGS WILL ACTUALLY BE A COUPLE OF DEGREES ABOVE NORMAL FOR
EARLY MAY.
TONIGHT...CLOUDS WILL INCREASE AHEAD OF A WEAK UPPER LEVEL
DISTURBANCE AND ELEVATED WARM AIR ADVECTION AS NOTED ON FORECAST
SOUNDINGS. HOWEVER...MOISTURE IN THE LOW LEVELS WILL BE LIMITED SO
HAVE ONLY MENTIONED SMALL POPS FOR LATE TONIGHT IN OUR FAR NW COUNTIES...
CLOSER TO THE APPROACHING DISTURBANCE. MODELS SUGGEST FRONTOGENESIS
IN NORTHERN KS AND NW MO WITH HIGH PRESSURE IN NORTHERN MN. THIS
WILL SET UP A NICE THERMAL RIBBON DEVELOPING ACROSS THE DVN CWA
WHICH WILL IMPACT TEMPERATURES. I WILL CONTINUE TO FORECAST MINIMUM
TEMPERATURES RANGING FROM AROUND 40 ALONG HIGHWAY 20 TO NEAR 50 IN
OUR FAR SOUTHERN CWA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CDT SAT MAY 3 2014
WARMING TREND STARTING EARLY NEXT WEEK WITH EPISODES OF THUNDERSTORMS
THAT COULD BE SEVERE THE MIDDLE OF NEXT WEEK.
OVERVIEW...INITIALIZATION AND VERIFICATION AVERAGE WITH BL MOISTURE
ISSUES THAT ARE TOO MOIST RESULTING IN TOO HIGH COVERAGE OF POPS AND
QPF AMOUNTS FOR WEAKLY FORCING SITUATIONS. RUN TO RUN VARIANCE AND
INTER SOLUTION TRENDS SUPPORTS USING A 60/40 MIX OF GFS AND HI-RES
ECMWF WITH BL TEMPS THAT MAY NEED RAISING IN WARM SECTOR BASED ON
VERIFICATION PAST 2 DAYS.
SUNDAY...HAVE TRIMMED POPS TO 20 TO 40 PERCENT OF LIGHT ELEVATED
SHOWERS NORTH AS FORCING AND MOISTURE LEVELS ARE MARGINAL WITH CLOUD
BASES AOA 5-8K AGL. SOUTH HALF OF FORECAST AREA SHOULD REMAIN DRY
WITH PARTLY CLOUDY SKIES AND MOSTLY CLOUDY SKIES NORTH. TEMPERATURES
A BIT OF A CHALLENGE WITH HIGHS LOWER TO MIDDLE 50S NORTH 1/3 TO NEAR
70F FAR SOUTH SECTIONS. NE WINDS OF 10 TO 20 MPH TO MAKE FOR A COOL
EARLY MAY DAY. ANY PRECIPITATION SHOULD SLIDE EAST BY EARLY
AFTERNOON. SUNDAY NIGHT...PARTLY TO MOSTLY CLEAR AND MINS TO SETTLE
IN THE UPPER 30S NE TO MID 40S SOUTH SECTIONS.
MONDAY AND TUESDAY...PARTLY CLOUDY WITH MID LEVEL CLOUDS AND EASTERLY
WINDS. HIGHS MOSTLY IN THE 60S ON MONDAY AND UPPER 60S TO MIDDLE
70S ON TUESDAY WITH LOWS IN THE 40S TUESDAY MORNING. COMFORTABLE
WEATHER FOR MAY.
TUESDAY NIGHT...WARM FRONT TO MOVE NORTH INTO AREA WITH FAVORABLE
FORCING FOR NOCTURNAL STORMS WITH 40+ KT LOW LEVEL JET. LOW FREEZING
LEVELS SUGGEST RISK OF LARGE HAIL AOA 1" IN DIAMETER WHICH WILL BE
MORE CLARIFIED NEXT 24 HOURS. QPF AMOUNTS GENERALLY SHOULD BE LIGHT
TO MODERATE WITH 30 TO 40 POPS REASONABLE ATTM. TEMPERATURES SHOULD
RISE DURING THE NIGHT AT MOST LOCATIONS BY MIDNIGHT.
WEDNESDAY...UNSETTLED AND RISK OF SHOWERS AND STORMS WITH SPEED OF
WARM FRONT A QUESTION. JET AXIS SUPPORTS MOST TO ALL OF AREA
SHOULD BE IN WARM SECTOR BY PM HOURS WITH HIGHS UPPER 70S TO LOWER
80S WITH DEWPOINTS TO NEAR 60 DEGREES. THIS WITH LOW LEVEL THERMAL
SHEAR PROFILES WOULD SUGGEST STRONG TO SEVERE STORM RISK. WEDNESDAY
NIGHT...MILD WITH LOWS UPPER 50S TO LOWER 60S AND POSSIBLE STORMS
DEPENDING ON HOW FAR NORTH WARM FRONT MOVES. LOW CONFIDENCE ATTM
WITH BEST ESTIMATE IS NEAR TO JUST NORTH OF HIGHWAY 20 CORRIDOR.
THURSDAY...WARM AND HUMID AND BLUSTERY WITH AFTERNOON TO EVENING
COLD FRONT TO PASS. SYNOPTIC FORCING TOOLS SUPPORTS STORMS WITH
SEVERE WITH HIGHS 75 TO 85 ATTM. LOCAL TECHNIQUES INDICATE A
TYPICAL LOW TO POSSIBLY MODERATE END SEVERE WEATHER OUTBREAK
SUGGESTED THAT SHOULD BE BETTER CLARIFIED NEXT 24 HOURS OF MAINLY
LARGE HAIL AND STRAIGHT LINE WINDS WITH ISOLATED TORNADO RISK AND
LOCALLY HEAVY RAINS. POPS MAY NEED RAISING IN THE PM HOURS. THURSDAY
NIGHT...POPS AGAIN MAY NEED RAISING WITH COOL FRONT PASSING WITH
CLEARING BY MORNING. LOWS MAY NEED TO BE LOWER IF COOL FRONT PASSES
FASTER.
FRIDAY...CLEARING WITH ANY LINGERING SHOWERS ENDING WITH NEAR
SEASONABLE TEMPERATURES WITH HIGHS AROUND 70F AND LOWS UPPER 40S TO
MIDDLE 50S FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1225 PM CDT SAT MAY 3 2014
HIGH PRESSURE BUILDING FROM THE NORTHERN PLAINS INTO THE WESTERN
GREAT LAKES BY SUNDAY AFTERNOON WILL TURN SURFACE WINDS TO THE
NORTH TONIGHT AND NORTHEAST SUNDAY MORNING. VFR FLIGHT CONDITIONS
ARE EXPECTED THROUGH MID DAY SUNDAY DESPITE A COUPLE OF WEAK
SYSTEMS MOVING THROUGH. THE FIRST IS CURRENTLY OVER EASTERN
NEBRASKA AND SOUTH DAKOTA AND WAS PRODUCING SOME LIGHT RAIN. THIS
FEATURE MAY BRUSH SOUTHEAST IOWA AND NORTHEAST MISSOURI LATE THIS
AFTERNOON AND COULD CAUSE A FEW SPRINKLES. CEILINGS THOUGH SHOULD
REMAIN NEAR OR ABOVE 8KFT. ANOTHER DISTURBANCE WILL MOVE THROUGH
SUNDAY MORNING BRINGING SOME LIGHT RAIN TO PARTS OF EASTERN IOWA
AND NORTHERN IL. AGAIN CIGS AND VSBYS WITH THIS FEATURE SHOULD
REMAIN VFR.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...DLF
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...NICHOLS
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
258 PM MDT SAT MAY 3 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 206 PM MDT SAT MAY 3 2014
FRONT CURRENTLY DRAPE ACROSS THE FORECAST AREA. 70S ARE OVER THE
NORTHEAST HALF WITH 80S OVER THE SOUTHWEST HALF. THIS BOUNDARY
WILL MAKE FOR A DIFFICULT WIND AND TEMPERATURE FORECAST THROUGH
TOMORROW. TEMPERATURES SHOULD STAY WARM WHERE THE WINDS STAY UP.
SOME LOCATIONS ON BOTH SIDES WILL HAVE LIGHTER WINDS SO COULD SEE
SOME LOCATIONS BEING ABLE TO DROP.
AS TODAY...MODELS DIFFER ON THE POSITION OF WHERE THE FRONT IS
DURING THE DAY. THE ECMWF IS FURTHER WEST WITH FRONT AND IS THE
COOLEST. OF THE MODELS THAT GO OUT LONG ENOUGH...THE NAM IS CLOSER
TO THE RAP AND HRRR WHICH ARE DOING WELL RIGHT NOW. MOST OF THE
OUTPUT HOW MORE OF THE FORECAST ON THE WARM SIDE...AND WILL BE
GOING THAT DIRECTION. AT THIS TIME THE NORTHEAST CORNER LOOKS TO
BE THE COOLEST WITH SUMMER-LIKE TEMPERATURES EXPECTED OVER TO THE
WEST OF THE FRONT. REFER TO THE CLIMATE SECTION BELOW. ALSO REFER
TO THE FIRE SECTION BELOW FOR TOMORROWS FIRE WEATHER DISCUSSION.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 258 PM MDT SAT MAY 3 2014
MAIN CONCERNS WITH THE EXTENDED FORECAST ARE POSSIBLE FIRE WEATHER
CONDITIONS AND PRECIPITATION ASSOCIATED WITH A PASSING LONGWAVE
TROUGH.
WARM AND DRY CONDITIONS ARE ANTICIPATED INTO THE BEGINNING OF NEXT
WEEK. A SLOW COOLING TREND SHOULD BEGIN MONDAY WITH COOLING 850 MB
TEMPERATURES AND A WEAK COLD FRONT LINGERING. MUCH HIGHER DEWPOINTS
AND HUMIDITY SHOULD POOL ALONG AND BEHIND THE COLD FRONT...ALLOWING
FOR A CHANCE OF FOG BOTH SUNDAY NIGHT AND MONDAY NIGHT. DURING THE
DAYLIGHT HOURS...CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE SOUTH OF
THE FRONT WHERE SOUTHWEST WINDS INCREASE AND VERY DRY AIR REMAINS.
FUEL STATUS REMAINS THE MAIN ISSUE WITH GREEN-UP ONGOING ACROSS THE
TRI-STATE AREA.
A STRONG LONGWAVE TROUGH SWINGS ACROSS THE HIGH PLAINS DURING THE
MIDDLE OF THE WEEK...BRINGING THE ONLY CHANCES FOR PRECIPITATION IN
THE LONG TERM FORECAST. DUE TO DRY AIR REMAINING ACROSS PORTIONS OF
THE TRI-STATE AREA...PRECIPITATION CHANCES WILL BE CONFINED TO
LOCATIONS ALONG AND BEHIND THE FRONT WHERE AVAILABLE MOISTURE IS
HIGHER. THE DRYLINE REMAINS WELL TO THE EAST DURING PERIODS OF BEST
ATMOSPHERIC LIFT AND INSTABILITY SO BEST CHANCES FOR SEVERE
WEATHER SHOULD BE CONFINED TO EASTERN KANSAS AND OKLAHOMA. WITH
INCREASING SHEAR AND INSTABILITY...CAN NOT RULE OUT A FEW STRONG TO
SEVERE STORMS BUT DO NOT THINK A WIDESPREAD OUTBREAK IS LIKELY AT
THIS TIME. PRECIPITATION SHOULD BE SPORADIC SO NOT EVERYBODY WILL
RECEIVE A NEEDED RAINFALL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1143 AM MDT SAT MAY 3 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. DUE TO A FRONTAL
BOUNDARY MAKING SUBTLE MOVEMENTS BACK AND FORTH ACROSS THE AREA...WINDS
WILL BE VARIABLE SHIFTING THROUGH THE MOST OF THE PERIOD...ESPECIALLY
AT KMCK. THE WINDS WILL BECOME MORE WESTERLY AND GUSTY AT KGLD
DURING THE MID TO LATE MORNING HOURS ON SUNDAY.
&&
.FIRE WEATHER...
ISSUED AT 206 PM MDT SAT MAY 3 2014
LIKE TODAY...THE RELATIVE HUMIDITIES WILL DEFINITELY REACH
CRITICAL FIRE WEATHER CONDITIONS. HOWEVER...THERE IS SOME
UNCERTAINTY ON FUEL STATUS AND ON THE WINDS. WHAT DATA CAN BE
FOUND WOULD INDICATE THAT WE ARE IN GREEN-UP BUT THAT MAY BE MOSTLY
FOR GROWING CROPS. WINDS TO THE WEST OF THE FRONT COULD BE GUSTY
AND REACH THE NEEDED CRITERIA. HOWEVER...THERE IS A DECENT SPREAD
IN THE MODEL OUTPUT ON THE POSITION OF THE FRONT AND RESULTANT
WIND SPEEDS. IF THE STRONGER NAM WINDS WORK OUT...THEN SOME
LOCATION IN THE SOUTHWEST HALF OF THE AREA COULD REACH CRITICAL
FIRE WEATHER CONDITIONS. AT THIS TIME...TOO MUCH UNCERTAINTY TO
ISSUE A WATCH WITH THE OVERNIGHT SHIFT NEEDING TO TAKE ANOTHER
LOOK AT THIS.
&&
.CLIMATE...
ISSUED AT 206 PM MDT SAT MAY 3 2014
MOST OF THE AREA WILL HAVE A CHANCE TO BREAK DAILY RECORDS FOR MAY
4. THE FOLLOWING ARE THE RECORDS FOR SUNDAY.
GOODLAND.....91 IN 2012
MCCOOK.......94 IN 2012
BURLINGTON...92 IN 1963
HILL CITY....93 IN 2012
COLBY........92 IN 1924
TRIBUNE......94 IN 1952
YUMA.........89 IN 1962
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...RRH
AVIATION...BULLER
FIRE WEATHER...BULLER
CLIMATE...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
227 PM MDT SAT MAY 3 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 206 PM MDT SAT MAY 3 2014
FRONT CURRENTLY DRAPE ACROSS THE FORECAST AREA. 70S ARE OVER THE
NORTHEAST HALF WITH 80S OVER THE SOUTHWEST HALF. THIS BOUNDARY
WILL MAKE FOR A DIFFICULT WIND AND TEMPERATURE FORECAST THROUGH
TOMORROW. TEMPERATURES SHOULD STAY WARM WHERE THE WINDS STAY UP.
SOME LOCATIONS ON BOTH SIDES WILL HAVE LIGHTER WINDS SO COULD SEE
SOME LOCATIONS BEING ABLE TO DROP.
AS TODAY...MODELS DIFFER ON THE POSITION OF WHERE THE FRONT IS
DURING THE DAY. THE ECMWF IS FURTHER WEST WITH FRONT AND IS THE
COOLEST. OF THE MODELS THAT GO OUT LONG ENOUGH...THE NAM IS CLOSER
TO THE RAP AND HRRR WHICH ARE DOING WELL RIGHT NOW. MOST OF THE
OUTPUT HOW MORE OF THE FORECAST ON THE WARM SIDE...AND WILL BE
GOING THAT DIRECTION. AT THIS TIME THE NORTHEAST CORNER LOOKS TO
BE THE COOLEST WITH SUMMERLIKE TEMPERATURES EXPECTED OVER TO THE
WEST OF THE FRONT. REFER TO THE CLIMATE SECTION BELOW. ALSO REFER
TO THE FIRE SECTION BELOW FOR TOMORROWS FIRE WEATHER DISCUSSION.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 226 AM MDT SAT MAY 3 2014
BY THE START OF THE EXTENDED PERIOD A DEEP RELATIVELY SLOW MOVING
UPPER LEVEL TROUGH WILL BE LOCATED WEST OF THE ROCKIES. A LEE SIDE
SURFACE TROUGH AND DRYLINE WILL BE POSITIONED OVER EASTERN COLORADO.
BY LATE TUESDAY INTO WEDNESDAY AS THE UPPER LEVEL TROUGH NEARS...A
SURFACE LOW WILL DEVELOP OVER THE FORECAST AREA. THE DRYLINE WILL BE
POSITIONED JUST EAST OF THE AREA ACROSS CENTRAL KANSAS. THE BEST LOW
LEVEL MOISTURE WILL RESIDE EAST OF THE DRYLINE AND ACROSS THE
NORTHERN PORTION OF THE FORECAST AREA WHERE EASTERLY/NORTHEASTERLY
LOW LEVEL FLOW WILL OCCUR ON THE NORTH SIDE OF SURFACE LOW. THE BEST
CHANCES OF CONVECTION WILL BE EAST OF THE DRYLINE AND NORTH OF THE
SURFACE LOW. A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT BRINGING
COOLER TEMPERATURES. SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE
UNTIL THE UPPER TROUGH AXIS MOVES THROUGH ON FRIDAY. CRITICAL FIRE
WEATHER CONDITIONS MAY DEVELOP ACROSS THE SOUTHERN PORTION OF THE
AREA TUESDAY AFTERNOON AND AGAIN ON WEDNESDAY AFTERNOON BEHIND THE
DRYLINE AS RH VALUES DROP BELOW 15 PERCENT AND WINDS POSSIBLY REACH
CRITERIA. SOME UNCERTAINTY REMAINS WITH THE PLACEMENT OF THE DRYLINE
AND SURFACE LOW AS WELL AS WINDS. THIS WILL NEED TO BE MONITORED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1143 AM MDT SAT MAY 3 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. DUE TO A FRONTAL
BOUNDARY MAKING SUBTLE MOVEMENTS BACK AND FORTH ACROSS THE AREA...WINDS
WILL BE VARIABLE SHIFTING THROUGH THE MOST OF THE PERIOD...ESPECIALLY
AT KMCK. THE WINDS WILL BECOME MORE WESTERLY AND GUSTY AT KGLD
DURING THE MID TO LATE MORNING HOURS ON SUNDAY.
&&
.FIRE WEATHER...
ISSUED AT 206 PM MDT SAT MAY 3 2014
LIKE TODAY...THE RELATIVE HUMIDITIES WILL DEFINITELY REACH
CRITICAL FIRE WEATHER CONDITIONS. HOWEVER...THERE IS SOME
UNCERTAINTY ON FUEL STATUS AND ON THE WINDS. WHAT DATA CAN BE
FOUND WOULD INDICATE THAT WE ARE IN GREENUP BUT THAT MAY BE MOSTLY
FOR GROWING CROPS. WINDS TO THE WEST OF THE FRONT COULD BE GUSTY
AND REACH THE NEEDED CRITERIA. HOWEVER...THERE IS A DECENT SPREAD
IN THE MODEL OUTPUT ON THE POSITION OF THE FRONT AND RESULTANT
WIND SPEEDS. IF THE STRONGER NAM WINDS WORK OUT...THEN SOME
LOCATION IN THE SOUTHWEST HALF OF THE AREA COULD REACH CRITICAL
FIRE WEATHER CONDITIONS. AT THIS TIME...TOO MUCH UNCERTAINTY TO
ISSUE A WATCH WITH THE OVERNIGHT SHIFT NEEDING TO TAKE ANOTHER
LOOK AT THIS.
&&
.CLIMATE...
ISSUED AT 206 PM MDT SAT MAY 3 2014
MOST OF THE AREA WILL HAVE A CHANCE TO BREAK DAILY RECORDS FOR MAY
4. THE FOLLOWING ARE THE RECORDS FOR SUNDAY.
GOODLAND.....91 IN 2012
MCCOOK.......94 IN 2012
BURLINGTON...92 IN 1963
HILL CITY....93 IN 2012
COLBY........92 IN 1924
TRIBUNE......94 IN 1952
YUMA.........89 IN 1962
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...BULLER
FIRE WEATHER...BULLER
CLIMATE...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1146 AM MDT SAT MAY 3 2014
.UPDATE...
ISSUED AT 933 AM MDT SAT MAY 3 2014
JUST COMPLETED AN UPDATE. MODELS HAVE A DIFFICULT TIME RESOLVING
RATHER COMPLEX SURFACE WIND/PRESSURE PATTERN OVER THE AREA. MODELS
TENDED TO BE TOO FAR EAST AND SOUTH WITH FEATURES. RAP/HRRR HAD GOOD
HANDLE ON THE CURRENT SETUP AND USED THEM FOR THE WIND FORECAST.
IT LOOKS LIKE NOW THE FRONT WILL BE FURTHER WEST AND A LITTLE
SLOWER TO START MOVING EAST. USED THE RAP FOR THE TEMPERATURES
TODAY WITH SOME SLIGHT ADJUSTMENTS MADE TO IT BASED ON LATEST TRENDS.
LATEST NAM/SREF LOOKED VERY CLOSE TO THE RAP BY LATER TODAY AND
USED THEM TO ADJUST THE WINDS/POSITION OF THE FRONT. ALSO ADJUSTED
SKY COVER DOWN THROUGH TONIGHT WITH SOME INCREASE EXPECTED
TOMORROW. ALSO LOWERED DEWPOINTS FOR TODAY BASED ON ITS BETTER
HANDLING OF THE WIND/TEMPERATURE FIELD PLUS 12Z SOUNDINGS SHOWING
A VERY WELL MIXED AND DRY AIR MASS WITH THE LOWEST DEWPOINTS IN
THE WESTERN PORTION. FORTUNATELY THE WINDS LOOK TO STAY BELOW
CRITICAL LEVELS SINCE RELATIVE HUMIDITIES WILL HAVE NO PROBLEM
DIVING TO VERY LOW VALUES THIS AFTERNOON...ESPECIALLY OUT WEST.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 226 AM MDT SAT MAY 3 2014
UPPER FLOW WILL BE NORTHWEST OVER THE CENTRAL PLAINS TODAY WITH A
RIDGE OVER THE ROCKIES. THE RIDGE WILL MOVE INTO THE PLAINS TONIGHT
AND SUNDAY AND RESIDE THERE THROUGH MONDAY. BY MONDAY NIGHT THE
RIDGE WILL SHIFT EAST INTO THE MISSOURI VALLEY WITH SOUTHWEST FLOW
EAST OF THE ROCKIES. A SURFACE TROUGH WILL BE PRESENT THROUGH SUNDAY
NIGHT EITHER IN EASTERN COLORADO OR ACROSS WESTERN KANSAS. A FRONT
WILL PUSH SOUTH INTO NORTHWEST KANSAS MONDAY WITH HIGH PRESSURE
BUILDING IN BEHIND IT. ANOTHER TROUGH WILL MOVE INTO EASTERN
COLORADO MONDAY NIGHT.
A COUPLE OF DISTURBANCE MOVE THROUGH THE FLOW SUNDAY AND MONDAY.
MOISTURE IS INSUFFICIENT FOR BOTH OF THE WAVES AS THEY COME THROUGH.
OTHERWISE SUBSIDENCE WILL BE PRESENT OVER THE FA TODAY AND TONIGHT
AS WELL AS SUNDAY AND MONDAY NIGHTS. THE NET RESULT WILL BE DRY
CONDITIONS THROUGH THIS ENTIRE FORECAST WITH NIL POPS.
MAX TEMPERATURES SHOULD RISE TO THE MID 80S TODAY AND AROUND 90
SUNDAY AND MONDAY. MIN TEMPERATURES TONIGHT AND SUNDAY NIGHT WILL
COOL TO THE UPPER 40S. MIN TEMPERATURES MONDAY NIGHT WILL BE
SLIGHTLY WARMER AROUND 50.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 226 AM MDT SAT MAY 3 2014
BY THE START OF THE EXTENDED PERIOD A DEEP RELATIVELY SLOW MOVING
UPPER LEVEL TROUGH WILL BE LOCATED WEST OF THE ROCKIES. A LEE SIDE
SURFACE TROUGH AND DRYLINE WILL BE POSITIONED OVER EASTERN COLORADO.
BY LATE TUESDAY INTO WEDNESDAY AS THE UPPER LEVEL TROUGH NEARS...A
SURFACE LOW WILL DEVELOP OVER THE FORECAST AREA. THE DRYLINE WILL BE
POSITIONED JUST EAST OF THE AREA ACROSS CENTRAL KANSAS. THE BEST LOW
LEVEL MOISTURE WILL RESIDE EAST OF THE DRYLINE AND ACROSS THE
NORTHERN PORTION OF THE FORECAST AREA WHERE EASTERLY/NORTHEASTERLY
LOW LEVEL FLOW WILL OCCUR ON THE NORTH SIDE OF SURFACE LOW. THE BEST
CHANCES OF CONVECTION WILL BE EAST OF THE DRYLINE AND NORTH OF THE
SURFACE LOW. A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT BRINGING
COOLER TEMPERATURES. SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE
UNTIL THE UPPER TROUGH AXIS MOVES THROUGH ON FRIDAY. CRITICAL FIRE
WEATHER CONDITIONS MAY DEVELOP ACROSS THE SOUTHERN PORTION OF THE
AREA TUESDAY AFTERNOON AND AGAIN ON WEDNESDAY AFTERNOON BEHIND THE
DRYLINE AS RH VALUES DROP BELOW 15 PERCENT AND WINDS POSSIBLY REACH
CRITERIA. SOME UNCERTAINTY REMAINS WITH THE PLACEMENT OF THE DRYLINE
AND SURFACE LOW AS WELL AS WINDS. THIS WILL NEED TO BE MONITORED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1143 AM MDT SAT MAY 3 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. DUE TO A FRONTAL
BOUNDARY MAKING SUBTLE MOVEMENTS BACK AND FORTH ACROSS THE AREA...WINDS
WILL BE VARIABLE SHIFTING THROUGH THE MOST OF THE PERIOD...ESPECIALLY
AT KMCK. THE WINDS WILL BECOME MORE WESTERLY AND GUSTY AT KGLD
DURING THE MID TO LATE MORNING HOURS ON SUNDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...FS
LONG TERM...BRB
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
643 PM EDT SAT MAY 3 2014
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS SOUTHERN AREAS
THROUGH THIS EVENING. LOW PRESSURE WILL DEVELOP TO OUR WEST
TONIGHT AND TRACK ACROSS THE STATE ON SUNDAY. THE LOW WILL
CONTINUE EAST ACROSS THE MARITIMES SUNDAY NIGHT AND MONDAY.&&
.NEAR TERM /THROUGH SUNDAY/...
UPDATE: LGT SHOWERS ACROSS E CENTRAL AREAS ATTM BUT APPEAR TO BE
DIMINISHING W/ A MORE WDSPRD AREA OF SHOWERS FROM WRN MAINE BACK
ACROSS WRN NEW ENGLAND. THIS AREA ASSOCIATED W/ THE INITIAL SURGE
OF MOISTURE FROM THE SYSTEM TO AFFECT OUR REGION LATE TNGT THRU
SUN. ATTM GRIDS IN PRETTY GOOD SHAPE... JUST A MINOR ADJUSTMENT TO
BEEF UP CLDS A BIT AND ADJUST HRLY TEMPS WHICH ARE RUNNING A
LITTLE HYR THAN FCST.
UNSETTLED WEATHER WILL CONTINUE THIS TERM AND BEYOND.
THE FIRST BATCH OF SHOWERS WILL BE DIMINISHING AND EXITING INTO
NEW BRUNSWICK BY THE EVENING AS THE REGION GETS UNDER SOME UPPER
RIDGING. SOME BREAKS IN THE CLOUDS THIS AFTERNOON WILL HELP
TEMPERATURES TO REBOUND AFTER THE BRIEF SHOWER ACTIVITY TO AROUND
60F EVEN ACROSS THE NORTHERN CWA. TEMPERATURES WILL DROP OFF AFTER
SUNSET W/SOME PARTIAL CLEARING ESPECIALLY ACROSS THE CENTRAL AND
DOWNEAST, AND THEN LEVEL OFF AS CLOUDS WILL MOVE BACK IN LATER
TONIGHT AHEAD OF A MORE ROBUST SYSTEM MOVING OUT OF THE ONTARIO
REGION. DECIDED TO FOLLOW THE GEM AND RAP INTO TONIGHT W/A NICE
BREAK IN THE PRECIP UP THROUGH LATE EVENING. THIS FEATURE CAN BE
SEEN WELL ON THE LATEST SATELLITE WV IMAGERY W/ITS UPPER SUPPORT
MOVING INTO THE EASTERN GREAT LAKES. THEREFORE, OVERNIGHT LOWS ARE
EXPECTED TO BE IN THE LOW TO MID 40S. THIS ALL HINGES ON CLOUDS
ARRIVE SOONER AND DEWPOINTS DROPPING BACK DUE TO PARTIAL CLEARING
EARLY ON. THIS WILL NEED TO BE MONITORED. STEADIER RAINFALL IS
EXPECTED AFTER MIDNIGHT AND THIS WILL BE MOST PROMINENT ACROSS THE
WESTERN AND DOWNEAST.
SUNDAY WILL BE MOSTLY A WET DAY W/RAIN AS LOW PRES SLIDES ACROSS
THE CENTRAL PART OF THE STATE. AS THE LOW MOVES ACROSS THE REGION,
THE CENTRAL AND DOWNEAST REGION GET UNDER A SW FLOW FROM THE SFC
THROUGH 700MBS. THE IS POTENTIAL FOR SOME MID-LEVEL DRYING AND
W/THE COLD AIR ALOFT, THE AIRMASS DESTABILIZES W/SREF MUCAPES OF
300 J/KG. NAM/GFS SOUNDINGS SUPPORT K INDEX OF 30 AND TOTAL TOTALS
OF 55+. LIS DROP TO NEAR 0. THIS COULD BE ENOUGH TO ALLOW FOR SOME
CONVECTION AND DECIDED TO A CHANCE FOR TSTMS IN THE AFOREMENTIONED
AREAS BY THE AFTERNOON. FURTHER NORTH AND WEST, ATMOSPHERE LOOKS
TO BE STABLE ENOUGH KEPT THREAT FOR ANY TSTMS TO A MINIMUM IF NONE
AT ALL. HEAVIEST BAND OF RAINFALL IN THE CENTRAL AND DOWNEAST
AREAS WHERE BEST CONVERGENCE AND FORCING WILL BE SITUATED. SOME
DEFORMATION BANDING PRECIP POSSIBLE ESPECIALLY NORTH OF THE LOW.
TOTAL QPF FOR THE EVENT IS EXPECTED TO BE ON THE ORDER OF 0.30 TO
0.75". THIS ADDITIONAL WILL BE ADDED TO THE RIVER BASINS AND CAUSE
THE STAGES TO RISE SOME BUT NO PROBLEMS EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
LOW PRESSURE IS EXPECTED TO MOVE EASTWARD INTO THE ATLANTIC
SUNDAY NIGHT. A STRONG NORTHWEST PRESSURE GRADIENT WILL DEVELOP
ACROSS THE REGION BEHIND THE LOW AS HIGH PRESSURE BUILDS IN FROM
THE WEST. EXPECT SHOWERS TO PERSIST BEHIND THE LOW AS CYCLONIC
FLOW REMAINS BEHIND THE SYSTEM ALOFT. FOR POPS AND QPF WILL BLEND
THE NAM...GFS...SREF AND ECMWF. SKY COVER FROM THE
NAM...GFS...ECMWF. TEMPERATURE AND DEW POINT FROM HE SUPPER BLEND.
HAVE USED THE MOSG25 FOR SUSTAINED WIND SPEED.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE IS EXPECTED TO WEAKEN AND CREST THEN CREST OVER THE
REGION WEDNESDAY NIGHT. A WARM FRONT IS EXPECTED TO APPROACH FROM
THE SOUTH WEST THURSDAY AND FRIDAY THEN MOVE ACROSS THE STATE
SATURDAY. A COLD FRONT WILL THEN FOLLOW AS INTENSE LOW PRESSURE
MOVES ACROSS CENTRAL CANADA. WILL USE HE SUPPER BLEND TO POPULATE
ALL GRIDS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR GOING TO MVFR AFTER 06Z W/THE POTENTIAL FOR IFR
ACROSS KBGR AND KBHB SUNDAY MORNING AND THE IFR EDGING INTO THE
NORTHERN TERMINALS BY SUNDAY AFTERNOON. SOME IMPROVEMENT TO MVFR
FOR KBGR AND KBHB AND EVEN VFR AS THIS REGION GETS ON THE SOUTH
SIDE OF THE LOW AS SW FLOW SETS UP.
SHORT TERM: IFR CONDITIONS ARE EXPECTED SUNDAY NIGHT THEN
IMPROVING TO VFR CONDITIONS MONDAY. MVFR CONDITIONS EXPECTED
TUESDAY. VFR CONDITIONS WEDNESDAY AND THURSDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES ANTICIPATED THROUGH SUNDAY. THERE IS A SSW
SWELL ATTM ON THE WATERS W/WAVE HEIGHTS OF 3-4 FT. EXPECT THIS
SWELL TO CONTINUE INTO SUNDAY. A 30KT LLVL JET FROM 925-850MBS
IS FORECAST TO MOVE ACROSS THE WATERS LATER TONIGHT INTO EARLY
SUNDAY. THIS WILL BRING THE WINDS UP A BIT W/GUST TO 20 KTS
ESPECIALLY OVER THE OUTER WATERS.
SHORT TERM: FOR SUSTAINED WINDS WILL USE A BLEND OF THE SREF AND
GFS40 THEN TRANSITION TO THE SUPPER BLEND LATE TUESDAY. FOR WAVES:
WILL USE THE SWAN/NAM OUT TO 0000Z TUESDAY THEN TRANSITION TO THE
WNA/4.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...KHW/HEWITT
SHORT TERM...MIGNONE
LONG TERM...MIGNONE
AVIATION...KHW
MARINE...KHW/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
316 PM EDT SAT MAY 3 2014
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS SOUTHERN AREAS
THROUGH THIS EVENING. LOW PRESSURE WILL DEVELOP TO OUR WEST
TONIGHT AND TRACK ACROSS THE STATE ON SUNDAY. THE LOW WILL
CONTINUE EAST ACROSS THE MARITIMES SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
UNSETTLED WEATHER WILL CONTINUE THIS TERM AND BEYOND.
THE FIRST BATCH OF SHOWERS WILL BE DIMINISHING AND EXITING INTO
NEW BRUNSWICK BY THE EVENING AS THE REGION GETS UNDER SOME UPPER
RIDGING. SOME BREAKS IN THE CLOUDS THIS AFTERNOON WILL HELP
TEMPERATURES TO REBOUND AFTER THE BRIEF SHOWER ACTIVITY TO AROUND
60F EVEN ACROSS THE NORTHERN CWA. TEMPERATURES WILL DROP OFF AFTER
SUNSET W/SOME PARTIAL CLEARING ESPECIALLY ACROSS THE CENTRAL AND
DOWNEAST, AND THEN LEVEL OFF AS CLOUDS WILL MOVE BACK IN LATER
TONIGHT AHEAD OF A MORE ROBUST SYSTEM MOVING OUT OF THE ONTARIO
REGION. DECIDED TO FOLLOW THE GEM AND RAP INTO TONIGHT W/A NICE
BREAK IN THE PRECIP UP THROUGH LATE EVENING. THIS FEATURE CAN BE
SEEN WELL ON THE LATEST SATELLITE WV IMAGERY W/ITS UPPER SUPPORT
MOVING INTO THE EASTERN GREAT LAKES. THEREFORE, OVERNIGHT LOWS ARE
EXPECTED TO BE IN THE LOW TO MID 40S. THIS ALL HINGES ON CLOUDS
ARRIVE SOONER AND DEWPOINTS DROPPING BACK DUE TO PARTIAL CLEARING
EARLY ON. THIS WILL NEED TO BE MONITORED. STEADIER RAINFALL IS
EXPECTED AFTER MIDNIGHT AND THIS WILL BE MOST PROMINENT ACROSS THE
WESTERN AND DOWNEAST.
SUNDAY WILL BE MOSTLY A WET DAY W/RAIN AS LOW PRES SLIDES ACROSS
THE CENTRAL PART OF THE STATE. AS THE LOW MOVES ACROSS THE REGION,
THE CENTRAL AND DOWNEAST REGION GET UNDER A SW FLOW FROM THE SFC
THROUGH 700MBS. THE IS POTENTIAL FOR SOME MID-LEVEL DRYING AND
W/THE COLD AIR ALOFT, THE AIRMASS DESTABILIZES W/SREF MUCAPES OF
300 J/KG. NAM/GFS SOUNDINGS SUPPORT K INDEX OF 30 AND TOTAL TOTALS
OF 55+. LIS DROP TO NEAR 0. THIS COULD BE ENOUGH TO ALLOW FOR SOME
CONVECTION AND DECIDED TO A CHANCE FOR TSTMS IN THE AFOREMENTIONED
AREAS BY THE AFTERNOON. FURTHER NORTH AND WEST, ATMOSPHERE LOOKS
TO BE STABLE ENOUGH KEPT THREAT FOR ANY TSTMS TO A MINIMUM IF NONE
AT ALL. HEAVIEST BAND OF RAINFALL IN THE CENTRAL AND DOWNEAST
AREAS WHERE BEST CONVERGENCE AND FORCING WILL BE SITUATED. SOME
DEFORMATION BANDING PRECIP POSSIBLE ESPECIALLY NORTH OF THE LOW.
TOTAL QPF FOR THE EVENT IS EXPECTED TO BE ON THE ORDER OF 0.30 TO
0.75". THIS ADDITIONAL WILL BE ADDED TO THE RIVER BASINS AND CAUSE
THE STAGES TO RISE SOME BUT NO PROBLEMS EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
LOW PRESSURE IS EXPECTED TO MOVE EASTWARD INTO THE ATLANTIC
SUNDAY NIGHT. A STRONG NORTHWEST PRESSURE GRADIENT WILL DEVELOP
ACROSS THE REGION BEHIND THE LOW AS HIGH PRESSURE BUILDS IN FROM
THE WEST. EXPECT SHOWERS TO PERSIST BEHIND THE LOW AS CYCLONIC
FLOW REMAINS BEHIND THE SYSTEM ALOFT. FOR POPS AND QPF WILL BLEND
THE NAM...GFS...SREF AND ECMWF. SKY COVER FROM THE
NAM...GFS...ECMWF. TEMPERATURE AND DEW POINT FROM HE SUPPER BLEND.
HAVE USED THE MOSG25 FOR SUSTAINED WIND SPEED.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE IS EXPECTED TO WEAKEN AND CREST THEN CREST OVER THE
REGION WEDNESDAY NIGHT. A WARM FRONT IS EXPECTED TO APPROACH FROM
THE SOUTH WEST THURSDAY AND FRIDAY THEN MOVE ACROSS THE STATE
SATURDAY. A COLD FRONT WILL THEN FOLLOW AS INTENSE LOW PRESSURE
MOVES ACROSS CENTRAL CANADA. WILL USE HE SUPPER BLEND TO POPULATE
ALL GRIDS.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR GOING TO MVFR AFTER 06Z W/THE POTENTIAL FOR IFR
ACROSS KBGR AND KBHB SUNDAY MORNING AND THE IFR EDGING INTO THE
NORTHERN TERMINALS BY SUNDAY AFTERNOON. SOME IMPROVEMENT TO MVFR
FOR KBGR AND KBHB AND EVEN VFR AS THIS REGION GETS ON THE SOUTH
SIDE OF THE LOW AS SW FLOW SETS UP.
SHORT TERM: IFR CONDITIONS ARE EXPECTED SUNDAY NIGHT THEN
IMPROVING TO VFR CONDITIONS MONDAY. MVFR CONDITIONS EXPECTED
TUESDAY. VFR CONDITIONS WEDNESDAY AND THURSDAY.
&&
.MARINE...
NEAR TERM: NO HEADLINES ANTICIPATED THROUGH SUNDAY. THERE IS A SSW
SWELL ATTM ON THE WATERS W/WAVE HEIGHTS OF 3-4 FT. EXPECT THIS
SWELL TO CONTINUE INTO SUNDAY. A 30KT LLVL JET FROM 925-850MBS
IS FORECAST TO MOVE ACROSS THE WATERS LATER TONIGHT INTO EARLY
SUNDAY. THIS WILL BRING THE WINDS UP A BIT W/GUST TO 20 KTS
ESPECIALLY OVER THE OUTER WATERS.
SHORT TERM: FOR SUSTAINED WINDS WILL USE A BLEND OF THE SREF AND
GFS40 THEN TRANSITION TO THE SUPPER BLEND LATE TUESDAY. FOR WAVES:
WILL USE THE SWAN/NAM OUT TO 0000Z TUESDAY THEN TRANSITION TO THE
WNA/4.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...MIGNONE
LONG TERM...MIGNONE
AVIATION...HEWITT/MIGNONE
MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
308 PM EDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT SAT MAY 3 2014
WV IMAGERY AND RUC ANALYSIS SHOW AN UPPER TROUGH SITUATED OVER THE
GREAT LAKES REGION...WHILE AN UPPER RIDGE IS LOCATED OVER THE
WESTERN CONUS. THERE ARE A COUPLE EMBEDDED SHORTWAVES WITHIN THIS
UPPER TROUGH THAT WILL BE AFFECTING THE AREA OVER THE NEXT 24
HOURS. THE FIRST WAVE...WHICH IS CURRENTLY MOVING SOUTHEAST OUT OF
WESTERN LAKE SUPERIOR WAS PRODUCING SCATTERED/NUMEROUS SHOWERS OVER
NORTHWEST ONTARIO AND NORTHEAST MINNESOTA THIS PAST EVENING
AND IS NOW PUSHING A NORTH/SOUTH LINE OF SHOWERS ACROSS
WESTERN UPPER MICHIGAN. MODELS HAVE A GOOD AGREEMENT ON THE
EASTWARD MOVEMENT OF THESE SHOWERS AS THE FORCING FROM THE
SHORTWAVE...LEFT FRONT OF THE UPPER JET...MID LEVEL Q-VECTOR
CONVERGENCE...AND THE SURFACE TROUGH STRETCHING SOUTHWEST FROM
THE LOW CENTERED IN SOUTHERN HUDSON BAY MOVE TO THE EAST-SOUTHEAST.
RAINFALL AMOUNTS SHOULDN/T BE MUCH MORE THAN 0.05 TO 0.15 WITHIN
THE HEAVIEST PART OF THESE SHOWERS...WHICH IS SIMILAR TO THE 0.13
INCH RECEIVED AT IRONWOOD AWOS.
BEHIND THE WAVE...SOME MID LEVEL DRYING SEEN UPSTREAM (ASSOCIATED
WITH Q-VECTOR DIVERGENCE) MAY LEAD TO SOME BREAKS IN THE CLOUDS OVER
THE WESTERN CWA (ESPECIALLY NEAR THE WISCONSIN BORDER) AND HAVE
TRENDED TOWARDS A MUCH DRIER FORECAST THAN PREVIOUSLY SHOWN DURING
THE AFTERNOON. THAT IDEA FOLLOWS QPF OUTPUT BY THE MODELS FOR
WESTERN UPPER MICHIGAN...BEFORE THE NEXT WAVE APPROACHES AND BRINGS
INCREASING MID LEVEL MOISTURE FOR TONIGHT. IR SATELLITE AND SURFACE
OBS INDICATE A POCKET OF LOW LEVEL MOISTURE OVER NORTHEAST MINNESOTA
AND NORTHWEST ONTARIO THAT IS PRODUCING CEILINGS AT OR BELOW 1KFT.
THIS COMPLICATES THE SKY COVER FORECAST...AS MODELS INDICATE THIS
LOW CLOUD DECK WILL MOVE INTO THE WESTERN U.P. OVER THE NEXT COUPLE
OF HOURS (STARTING TO SEE HINTS OF IT AT KIWD AT 4AM). WILL
CONTINUE TO HAVE THOSE CLOUDS THROUGH MOST OF THE MORNING BEFORE
THE MODELS SHIFT THE MOISTURE NORTHEAST AND INCREASED MIXING
DEVELOPS. EXPECT THIS NORTHEAST MOVEMENT TO PRODUCE SOME PARTLY
CLOUDY SKIES OVER PORTIONS OF SOUTHWEST UPPER MICHIGAN...ESPECIALLY
ALONG THE WISCONSIN BORDER. THE INCREASE IN MIXING TODAY WILL
PRODUCE SOME GUSTY WEST-NORTHWEST WINDS OVER THE WESTERN 2/3RDS OF
THE CWA BEHIND THE TROUGH. TRENDED WINDS UP IN THOSE AREAS DUE TO
BETTER MIXING SHOWN ON 00Z MODEL RUNS. EXPECT SUSTAINED WINDS IN THE
10-15MPH RANGE WITH GUSTS OF 20-25MPH TO MAYBE EVEN 30MPH OVER THE
KEWEENAW PENINSULA. THESE INCREASED WINDS AND SLIGHTLY DRYER LOW
LEVEL AIR SHOULD HELP TO SCOUR OUT ANY REMAINING FOG OVER THE
EASTERN U.P. THIS MORNING. DID LINGER SOME FOG OVER CENTRAL/EASTERN
PORTIONS OF LAKE SUPERIOR...BUT SHOWED A DIMINISHING TREND WITH THE
DRIER WESTERLY FLOW. FINALLY...HIGHS TODAY LOOK TO BE IN THE UPPER
40S TO LOW/MID 50S...WITH THE HIGHEST VALUES NEAR THE WISCONSIN
BORDER UNDER THE EXPECTATIONS OF SOME SUNSHINE IN THE AFTERNOON.
THE SECOND WAVE...CURRENTLY NORTH OF LAKE WINNIPEG...IS EXPECTED
TO IMPACT THE AREA LATE THIS AFTERNOON AND INTO TONIGHT. WITH THE
TRACK OF THE WAVE AND ITS MERGING WITH ENERGY ROUNDING THE UPPER
RIDGE...THERE IS THE POTENTIAL FOR A FEW SHOWERS ALONG THE
WISCONSIN BORDER LATE THIS AFTERNOON AND THROUGH THE EVENING HOURS.
CONFIDENCE IS LOW ON THE RAIN POTENTIAL...DUE TO MID LEVEL Q-VECTOR
DIVERGENCE...AND WITH LIMITED MODEL QPF AMOUNTS...OPTED TO STICK
WITH SLIGHT AND LOW CHANCE POPS. THE OTHER OPPORTUNITY FOR
PRECIPITATION WILL COME LATE TONIGHT AND INTO SUNDAY MORNING. THE
TROUGH THAT SLIDES THROUGH THE AREA THIS MORNING AND EARLY AFTERNOON
WILL BECOME A CLOSED LOW OVER SOUTHEAST ONTARIO AND SWEEP A
SECONDARY TROUGH ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT. BEST
FORCING/MOISTURE OVER NORTHEAST HALF TO THIRD OF THE CWA...CLOSER TO
THE SECONDARY SURFACE TROUGH...SO WILL KEEP CHANCE POPS OVER
NORTHEAST LAKE SUPERIOR AND LIMIT POPS OVER THE LAND AREAS NEAR
LAKE SUPERIOR TO SLIGHT CHANCES. THE LATEST TRENDS IN THE 00Z
MODELS SEEM TO DELAY THE PRECIP TOWARDS SUNDAY MORNING. IF SHOWERS
HAPPEN...DRY LOWER LEVEL AIR WILL LEAD TO COOLING OF THE COLUMN TO
THE WETBULB TEMP. WITH THE WETBULB0 VALUES AROUND
1600-3000FT THIS EVENING BEFORE FALLING TO THE SURFACE FROM
WEST TO EAST OVERNIGHT...EXPECT THE PRECIP TO BE RAIN
INITIALLY...BEFORE TRANSITIONING TO A RAIN/SNOW MIX AND EVENTUALLY
ALL SNOW (AS COLDER AIR ALOFT SLIDES SOUTHEAST OVER THE AREA). A
TIGHTENING GRADIENT AHEAD OF THE SECONDARY TROUGH WILL KEEP A STEADY
WEST TO EVENTUALLY NORTHWEST WIND GOING THROUGH THE NIGHT...WITH THE
STRONGEST WINDS NEAR LAKE SUPERIOR AND OVER THE KEWEENAW PENINSULA
TOWARDS DAYBREAK (GUSTS TO 20-25MPH). LOWS TONIGHT LOOK TO BE IN
THE LOWER 30S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EDT SAT MAY 3 2014
NAM SHOWS A BROAD 500 MB RIDGE ACROSS THE PLAINS 12Z SUN WITH A
TROUGH IN THE UPPER GREAT LAKES AND ANOTHER IN THE PACIFIC NW. THE
RIDGE AMPLIFIES WITH TIME SUN INTO MON NIGHT ACROSS THE PLAINS AS
THE TROUGH IN THE PACIFIC NW DIGS INTO THE WESTERN U.S.
LOOKS PRETTY QUIET THIS FORECAST PERIOD WITH RAIN AND SNOW SHOWERS
MOVING OUT ON SUNDAY AND WILL GO DRY SUNDAY NIGHT THROUGH MONDAY
NIGHT. DID LOWER TEMPERATURES A BIT FOR SUNDAY NIGHT WITH RIDGING
ACROSS THE AREA AND CLEAR SKIES AND LIGHT WINDS WOULD ALLOW FOR
IDEAL RADIATIONAL COOLING CONDITIONS TO SET UP. MADE A FEW TWEAKS TO
TEMPERATURES ALONG THE LAKESHORES TO ACCOUNT FOR COOLER LAKE BREEZES
COMING IN OFF THE WATER/ICE AREAS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE ACROSS THE
PLAINS WITH A TROUGH IN THE WESTERN U.S. 12Z TUE. THE RIDGE GETS
AMPLIFIED AS IT MOVES INTO THE UPPER GREAT LAKES 12Z WED WHILE THE
TROUGH DIGS INTO THE ROCKIES WITH FURTHER AMPLIFICATION OF THE
PATTERN FOR 12Z THU AS THE TROUGH MOVES SLOWLY EASTWARD. THE TROUGH
MOVES INTO THE UPPER GREAT LAKES 12Z FRI. AS THE RIDGE POKES UP INTO
THE AREA...TEMPERATURES WILL BEGIN A WARMING TREND THIS FORECAST
PERIOD. GFS AND ECMWF SHOW 850 MB TEMPERATURES UP TO 13C ON THU AND
IF WE WOULD MIX THAT DOWN TO THE SFC...WOULD GET UP INTO THE MID
70S. ONLY PROBLEM IS WARM FRONT IS TO THE SOUTH AND THERE WILL BE
PLENTY OF CLOUDS AROUND SO THOSE TEMPERATURES WILL NOT BE REALIZED.
WITH WARM SECTOR STAYING MOSTLY TO THE SOUTH...HAVING THUNDER IN
THERE FOR WED NIGHT THROUGH THU NIGHT STILL LOOKS GOOD. ALSO LOOKS
LIKE THERE COULD BE SOME HEAVY RAIN AS AREA IS NORTH OF THE WARM
FRONT ALLOWING PLENTY OF MOISTURE TO OVERRUN THE WARM FRONT AND GET
WRUNG OUT OVER THE AREA. TEMPERATURES WILL SLOWLY WARM TO NEAR
NORMAL TOWARDS THE END OF THE FORECAST PERIOD. DID GO WITH HIGHER
POPS FOR WED NIGHT THROUGH THU NIGHT WITH WARM FRONT ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 202 PM EDT SAT MAY 3 2014
BREEZY CONDITIONS WILL LINGER THROUGH THE REMAINDER OF THE AFTERNOON
HOURS. EXPECT THE NEXT DISTURBANCE WILL APPROACH THE AREA LATE THIS
AFTERNOON AND TONIGHT. KIWD HAS THE BEST OPPORTUNITY FOR SHOWERS.
THE PRECIPITATION WILL LIKELY START AS RAIN...BUT IF IT IS STILL
OCCURRING OVERNIGHT IT WILL CHANGE TO SNOW. VFR TO MVFR CEILINGS
WILL BE POSSIBLE...AT CMX AND SAW FROM AROUND 09Z-15Z SUNDAY THANKS
TO UPSLOPE ENHANCEMENT OF THE NW WINDS BECOMING MORE N THROUGH THE
MORNING /PARTICULARLY AT SAW/. OTHERWISE...VFR CEILING AND VIS
SHOULD RETURN BY MID-LATE MORNING AS GUSTS IN THE 15-20KT RANGE
RETURN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 307 PM EDT SAT MAY 3 2014
LOW PRESSURE NEAR THE ONTARIO AND QUEBEC BORDER WILL DEEPEN ACROSS
MAINE ON SUNDAY. MEANWHILE...A RIDGE OF HIGH PRESSURE EXTENDING
ACROSS ND AND MN OVERNIGHT WILL BUILD ACROSS THE UPPER GREAT LAKES
ON SUNDAY...WHERE IT WILL REMAIN THROUGH TUESDAY...WITH WINDS
REMAINING AT OR BELOW 20KTS...AND LAKE BREEZES MONDAY AND TUESDAY.
THE AREA OF HIGH PRESSURE WILL EXIT EASTWARD LATE TUESDAY INTO
TUESDAY NIGHT AS 29.5 INCH LOW PRESSURE ORGANIZES ACROSS THE CENTRAL
PLAINS...WITH E-SE WINDS SWINGING IN ACROSS LAKE SUPERIOR. THE LOW
PRESSURE SYSTEM WILL SLIDE INTO E MM AND W LAKE SUPERIOR BY LATE
THURSDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 307 PM EDT SAT MAY 3 2014
STREAMS AND RIVERS WILL CONTINUE TO EXPERIENCE HIGHER LEVELS.
LOCATIONS STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE
STURGEON RIVER OVER HOUGHTON AND BARAGA COUNTIES...THE PAINT RIVER
NEAR CRYSTAL FALLS...THE STURGEON RIVER NEAR NAHMA JUNCTION AND
TAHQUAMENON RIVER NEAR PARADISE.
RIVERS OVER EASTERN UPPER MICHIGAN REMAIN NEARLY STEADY
STATE...SINCE THE HEAVIER PRECIPITATION SEEN IN THAT AREA WEDNESDAY
INTO THURSDAY HAS BEEN WORKING THROUGH THE BASINS AND THE
PRECIPITATION FROM TODAY HAS BEEN RELATIVELY LIGHT...AROUND 0.2IN OR
LESS. ONE INTERESTING ITEM TO NOTE IS THAT THE TAHQUAMENON RIVER
NEAR PARADISE IS CURRENTLY AT 9.58 FEET...WHICH IS THE 3RD HIGHEST
LEVEL ON RECORD /60 YEARS OF DATA/.
WITH A FEW INCHES OF SNOW WATER EQUIVALENT UPSTREAM OF THE STURGEON
RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER...THE
ONGOING SNOW MELT WILL CONTINUE TO FEED WATER INTO THEIR BASINS.
EXPECT MULTIPLE DAYS WITH TEMPS IN THE 40S AND 50S THOUGH THE MIDDLE
OF NEXT WEEK TO MELT THE REMAINING SNOW. THE MELT WILL BE SLOWED DOWN
THOUGH AS NIGHTTIME TEMPS WILL STILL BE IN THE LOWER TO MIDDLE 30S.
AFTER THE RAIN TOMORROW MORNING...THE NEXT CHANCE OF WIDESPREAD
RAINFALL WILL NOT OCCUR UNTIL NEXT WEDNESDAY OR THURSDAY. THOSE
LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO
MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KF
MARINE...KF
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
249 PM EDT SAT MAY 3 2014
.SYNOPSIS...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WEAK LOW PRESSURE WILL CROSS LOWER MICHIGAN TODAY...AND SLOWLY MOVE
OFF TO THE EAST. OUR LONG PERIOD OF WET WEATHER WILL FINALLY END BY
SUNDAY AFTERNOON...AS HIGH PRESSURE BUILDS SOUTHEAST FROM CENTRAL
CANADA. COOL WEATHER WILL CONTINUE INTO EARLY IN THE WORK WEEK...BUT
THINGS WILL TURN WARMER BY THURSDAY AND FRIDAY.
&&
.UPDATE...
ISSUED AT 248 PM EDT SAT MAY 3 2014
MAIN BATCH OF WIDESPREAD RAINFALL PUSHING THROUGH THE NE THIRD OF
THE CWA...ALONG WELL DEFINED SFC-MID LEVEL TROUGH AXIS. NW-SE
ORIENTED JET STREAK STRETCHES FROM THE NRN PLAINS INTO THE LOWER
GREAT LAKES AND STILL A FEW MORE SWIRLS ALONG THE NRN FRINGE OF
THE JET TO GET THROUGH OVER THE NEXT 24 HOURS OR SO. ONE SHORT
WAVE NOW PUSHING INTO NW LOWER MICHIGAN AND HAS HELPED TO EXPAND
HEATING INDUCED SHOWER ACTIVITY BEHIND THE MAIN PRECIP LINE.
ANOTHER SHORT WAVE NOTED OVER FAR WESTERN ONTARIO THAT WILL SLIDE
THROUGH TONIGHT.
THIS AFTERNOON...INITIAL BATCH OF RAINFALL WILL CONTINUE TO LIFT
NE SLOWLY OUT OF THE REGION ALTHOUGH HEATING AND SHORT WAVE
INDUCED SHOWERS WILL BE PREVALENT ACROSS INTERIOR NRN LOWER
MICHIGAN FOR A FEW MORE HOURS. HAVE TAILORED AFTERNOON POPS IN
THAT DIRECTION. DID GET A REPORT OF ICE PELLETS WITHIN THESE
SHOWERS NEAR BEAVERTON...NOT SURPRISING GIVEN THE COLD AIR ALOFT.
AND THOUGHT ABOUT ADDING ICE PELLETS TO THE FORECAST
ACCORDINGLY...ALTHOUGH IT/S MORE OF A GEE WHIZ THING THAN
ANYTHING.
UPDATE ISSUED AT 1041 AM EDT SAT MAY 3 2014
NW-SE ORIENTED UPPER TROUGH AXIS NOW SLIDING INTO THE GREAT LAKES.
ONE VORTICITY MAX AND ATTENDING SFC LOW/TROUGH PUSHING THROUGH
EASTERN LOWER MICHIGAN DRIVING A FAIRLY EXPANSIVE BATCH OF
RAINFALL THROUGH THE SE HALF OF THE CWA. ANOTHER STRETCHED OUT
BAND OF PRECIP EXTENDS BACK INTO CENTRAL AND EASTERN UPPER
MICHIGAN ALONG THE MID LEVEL SHEAR AXIS.
WHOLE CONGLOMERATION OF PRECIP WILL CONTINUE TO SWING EASTWARD
THROUGH THE REGION OVER THE NEXT FEW HOURS BRINGING A PERIOD OF
CATEGORICAL PRECIP TO THE CWA. BEHIND THE TROUGH...SHARP CLEARING
LINE AND DRIER AIR NOTED UPSTREAM THAT WILL SPREAD EASTWARD INTO
THE CWA DURING THE COURSE OF THE AFTERNOON (ALREADY HAPPENING IN
THE SW COUNTIES). HAVE TWEAKED POPS ACCORDINGLY. BUT...WITH -28C
OR COLDER MID LEVEL AIR SLIPPING INTO NRN MICHIGAN THIS AFTERNOON/
HEATING AND SOME RESULTING INSTABILITY...CERTAINLY THINK SHOWERS
WILL POP UP THIS AFTERNOON...LIKELY DOWNWIND OVER THE HIGHER
TERRAIN INTO THE E/S PART OF THE CWA...LASTING INTO THE EVENING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT SAT MAY 3 2014
CURRENTLY, SFC TROUGH/WEAK COLD FRONT IS BEGINNING TO MOVE ACROSS
NORTHERN LAKE MICHIGAN WITH A 500 MB SHORTWAVE TROUGH/SPEED MAX
DIVING INTO THE MAIN 500 MB TROUGH CURRENTLY OVER THE UPPER GREAT
LAKES. THERE ARE SOME SHOWERS ASSOCIATED WITH THIS WAVE. TO THE
WEST, THERE IS A DECENT AREA OF SUBSIDENCE AND DRYING IN THE UPPER
MISSISSIPPI VALLEY. THE RAIN SHOWERS AND THE DRYING WILL BE THE MAIN
CONCERNS WITH THIS PACKAGE.
TODAY...WHILE THE GFS AND ECMWF MODELS HAVE SIMILAR CONFIGURATION
WITH THE QPF, THE GFS IS MORE INTENSE, SO THINKING THAT THERE HAS
BEEN A LITTLE GRID SCALE FEEDBACK. HOWEVER, WITH THAT SAID THE MASS
FIELDS ARE COMPARABLE BETWEEN THE TWO. THE NAM LOOKS SIMILAR TO THE
GFS WITH THE SFC LOW MOVING INTO WC LOWER, AND SPREADING RAIN
FARTHER NORTH INTO THE FORECAST AREA. THE RUC13 SEEMS TO BE HANDLING
THE PRECIPITATION LIKE THE ECMWF, WHICH SEEMS TO BE FOLLOWING THE
CURRENT TRENDS OF THE RADAR ATTM. IT LOOKS LIKE THERE WILL BE A
NUMEROUS RAIN SHOWERS ALONG AND SOUTH OF M-72 AS SFC TROUGH MOVES TO
THE EAST BETWEEN US-10 AND I-96 DOWNSTATE. THERE IS A SECOND AREA OF
LIGHT RAIN BETWEEN AND KRRL AND W LAKE SUPERIOR. WHICH WILL SWEEP
THROUGH UPPER MICHIGAN AND AREAS NORTH OF M-32 THIS MORNING. BY 18Z,
THE RAIN WILL LIKELY BE ON THE EAST SIDE OF THE STATE AS THE DRY AIR
NOTED IN THE MISSISSIPPI VALLEY NOW, SHOULD BE PUSHING INTO NW LOWER
AND C UPPER.
TONIGHT...AS THE DRY AIR PUSHES THROUGH THE REGION, THERE WILL STILL
BE SOME MOISTURE IN THE LOWER LEVELS (850 MB AND LOWER RH IS AROUND
70%) AND WITH ANOTHER 500 MB SHORTWAVE TROUGH ROTATING THROUGH LAKE
SUPERIOR, THAT WE GE THE CHANCE FOR RAIN SHOWERS, MIXED WITH SOME
SNOW IN E UPPER, AS THE 850 MB TEMPERATURES FALL TO AROUND -4C WITH
THE SFC TEMPERATURES FALLING TO THE MID 30S. THERE COULD ALSO BE
SOME SNOW MIXING IN WITH THE RAIN IN THE N LOWER HIGHLANDS, AROUND
GAYLORD AS TEMPERATURES FALL TO THE MID 30S THERE AS WELL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 331 AM EDT SAT MAY 3 2014
THERE APPEAR TO BE ACTUAL CHANGES ON THE HORIZON. UPPER FLOW FINALLY
GETS UNSTUCK AND BECOMES MORE PROGRESSIVE. AFTER ONE FINAL SHORTWAVE
SQUEEZES BY SUPERIOR/EASTERN UPPER MI EARLY SUNDAY...RIDGING OUT
WEST WILL SLOWLY BUILD EAST INTO THE PLAINS AND UPPER MS VALLEY. AT
THE SURFACE...WEAK HIGH PRESSURE NOSES IN FROM THE NW...AND HANGS
OUT THRU MONDAY. THE AIRMASS IS INITIALLY STILL QUITE COOL...AND
SUBSTANTIAL WARM ADVECTION WILL NOT BE SEEN AT LOW LEVELS UNTIL
LATER IN THE WEEK. BUT OUR AIRMASS WILL MODERATE IN PLACE AS EARLY
MAY SUNSHINE FINALLY GETS A CHANCE TO DO SOMETHING. SO SUNNIER AND
MILDER WX IS IN STORE EVENTUALLY...THOUGH THE NIGHTS WILL STILL BE
SEASONABLY COOL.
SUNDAY...ANOTHER SHOT OF COLD ADVECTION WILL BE UNDERWAY AT THE
START OF THE DAY...BEHIND A COLD FRONT ADVANCING INTO SOUTHERN LOWER
MI. A FAIRLY POTENT 500MB VORT RIBBON WILL EXTEND FROM ISLE ROYALE
TO CENTRAL LAKE HURON IN THE MORNING. IT/S PROGRESS EASTWARD WILL
SET US UP FOR SUBSTANTIAL NVA AND DEEP DESCENT BY MID/LATE
AFTERNOON. BUT UNTIL THEN...WE/LL BE FIGHTING OFF A SHOWER THREAT
FOR A FEW MORE HOURS. BEST CHANCE FOR PRECIP SHOULD BE BENEATH AND
NORTH OF THE VORT RIBBON. SOME DPVA DYNAMICS WILL BE FOUND BENEATH
THE RIBBON. TO THE NORTH...WE WILL SEE THE COLDEST TEMPS ALOFT (-32C
AT 500MB OVER EASTERN UPPER AT 12Z) AND CORRESPONDING STEEP LAPSE
RATES (700-500MB LAPSE RATES 7.5-7.75C/KM). SOME POTENTIAL FOR MIXED
PRECIP OVER EASTERN UPPER AND ESPECIALLY THE HIGH TERRAIN OF
NORTHERN LOWER MI...WHERE THE MELTING LAYER LOWERS TO AROUND 1K FT
THICK. WILL CUT OFF PRECIP AT 16Z...THOUGH COLD-AIR CUMULUS WILL
MAINTAIN PARTLY TO MOSTLY CLOUDY SKIES. THE CHILLY AIRMASS (850MB
TEMPS -3 TO -4C) AND LIMITED SUNSHINE WILL KEEP MAX TEMPS IN THE
UPPER 40S TO LOWER 50S...PERHAPS A BIT WARMER IN THE FAR SE.
SUN NIGHT/MONDAY...WITH LOSS OF HEATING...CU FIELD SHOULD DIMINISH
WITH TIME SUNDAY EVENING IN NORTHERN LOWER. SOME SIGNS OF MSLP
TROFFING AND ASSOCIATED 1000-850MB CONVERGENCE HANGING AROUND
EASTERN UPPER FOR MUCH OF THE NIGHT. THAT WOULD HELP SOME RESIDUAL
STRATOCU LINGER FOR MUCH OF THE NIGHT OVER FAR NORTHERN LOWER AND
POINTS NORTH. THE ARRIVAL OF BUBBLE HIGH PRESSURE SHOULD DIMINISH
THE LOW CLOUD PRESENCE ON MONDAY. HOWEVER...THE LEFTOVER FRONT FROM
THE OHIO VALLEY INTO THE DAKOTAS WILL BECOME MORE ACTIVE...WITH SOME
ASSOCIATED HIGH CLOUD DEBRIS ENTERING THE REGION FROM THE WEST.
STILL...THINGS LOOKS PARTLY SUNNY AT WORST.
MIN TEMPS IN THE UPPER 20S TO LOWER 30S...THOUGH SOME OF THE USUAL
COLD SPOTS WILL DIP A LITTLE LOWER. MAX TEMPS 50 TO 60F.
REST OF THE FORECAST...UPSTREAM 500MB RIDGE AXIS WILL AMPLIFY A BIT
BY THE TIME IT MOVES OVERHEAD EARLY THURSDAY. AN UPPER LOW STALLED
OVER THE CANADIAN PRAIRIE WILL EVENTUALLY HELP PUSH THE RIDGE EAST
AND/OR SUPPRESS IT TOWARD NEXT...THOUGH THE MANNER IN WHICH THIS
HAPPENS IS STILL UNCERTAIN. REGARDLESS...THIS IS A MUCH WARMER
PATTERN...AND TEMPS WILL CLIMB AS WE PROGRESS THRU THE WORK WEEK.
HOWEVER...THE EXTENDED MODELS ARE IN GOOD AGREEMENT IN PUSHING MCS/S
INTO THE RIDGE AXIS BEGINNING AS SOON AS WED NIGHT. THIS HAS CLEAR
POTENTIAL TO MESS UP OTHERWISE WARM WX...AND WILL NOT GO WILD WITH
MAX TEMPS LATE IN THE WEEK AT THIS TIME.
AS FOR PRECIP...INITIAL SURGE OF WARM ADVECTION COULD PRODUCE SOME
SHRA ON WED (THOUGH WILL LEAVE OUT THUNDER). THINGS GRADUALLY GET
STORMIER INTO THURSDAY/THU NIGHT. FRIDAY LOOKS HIGHLY UNCERTAIN AS
THIS TIME...DEPENDING ON TIMING WE MAY TRY TO DRY OUT BEHIND A WEAK
COLD FRONT (ECMWF) OR NOT SEE FROPA UNTIL FRIDAY NIGHT (GFS). SO
CHANCY POPS STILL IN ORDER THAT FAR OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 248 PM EDT SAT MAY 3 2014
MVFR CONDITIONS WILL PREVAIL FOR THE BALANCE OF THE AFTERNOON WITH
SHOWERS AT TVC/PLN/APN. SHOWER ACTIVITY FADES THIS EVENING AND
CONDITIONS SHOULD IMPROVE TO VFR FOR A TIME. HOWEVER...GIVEN THE
RAINFALL AND WEAKENING WINDS...THERE IS THE POTENTIAL FOR FOG
LATER THIS EVENING ALTHOUGH SFC WINDS MAY STAY JUST STRONG ENOUGH
TO CURTAIL THAT THREAT. THEN...ANOTHER BOUT OF LIGHT SHOWERS
OVERNIGHT AS MID LEVEL SHORT WAVE SLIPS DOWN THROUGH NRN MICHIGAN...
ALTHOUGH THINK CIGS REMAIN VFR. BUT ON SUNDAY...MVFR CONDITIONS
RETURN DUE TO DAYTIME HEATING.
&&
.MARINE...
ISSUED AT 331 AM EDT SAT MAY 3 2014
WINDS TODAY WILL BEGIN TO VEER IN THE AFTERNOON AS THE FRONT MOVES
THROUGH THE REGION, AND ONCE WINDS ARE OUT OF THE NW THEY SHOULD
INCREASE A BIT TONIGHT. HOWEVER, THE PRESSURE GRADIENT BEGINS TO
TIGHTEN AND THE FAVORED COASTAL CONVERGENCE AREA, FROM THE MACKINAC
BRIDGE TO PRESQUE ISLE LIGHT WILL PROBABLY SEE SMALL CRAFT GUSTS AND
POSSIBLY WAVES EARLY ON SUNDAY, THEN AS THE HIGH BUILDS INTO THE
UPPER GREAT LAKES IN THE AFTERNOON AND NIGHT, THE WINDS WILL
DIMINISH.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...ADAM
SYNOPSIS...JZ
SHORT TERM...JL
LONG TERM...JZ
AVIATION...ADAM
MARINE...JL
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
207 PM EDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT SAT MAY 3 2014
WV IMAGERY AND RUC ANALYSIS SHOW AN UPPER TROUGH SITUATED OVER THE
GREAT LAKES REGION...WHILE AN UPPER RIDGE IS LOCATED OVER THE
WESTERN CONUS. THERE ARE A COUPLE EMBEDDED SHORTWAVES WITHIN THIS
UPPER TROUGH THAT WILL BE AFFECTING THE AREA OVER THE NEXT 24
HOURS. THE FIRST WAVE...WHICH IS CURRENTLY MOVING SOUTHEAST OUT OF
WESTERN LAKE SUPERIOR WAS PRODUCING SCATTERED/NUMEROUS SHOWERS OVER
NORTHWEST ONTARIO AND NORTHEAST MINNESOTA THIS PAST EVENING
AND IS NOW PUSHING A NORTH/SOUTH LINE OF SHOWERS ACROSS
WESTERN UPPER MICHIGAN. MODELS HAVE A GOOD AGREEMENT ON THE
EASTWARD MOVEMENT OF THESE SHOWERS AS THE FORCING FROM THE
SHORTWAVE...LEFT FRONT OF THE UPPER JET...MID LEVEL Q-VECTOR
CONVERGENCE...AND THE SURFACE TROUGH STRETCHING SOUTHWEST FROM
THE LOW CENTERED IN SOUTHERN HUDSON BAY MOVE TO THE EAST-SOUTHEAST.
RAINFALL AMOUNTS SHOULDN/T BE MUCH MORE THAN 0.05 TO 0.15 WITHIN
THE HEAVIEST PART OF THESE SHOWERS...WHICH IS SIMILAR TO THE 0.13
INCH RECEIVED AT IRONWOOD AWOS.
BEHIND THE WAVE...SOME MID LEVEL DRYING SEEN UPSTREAM (ASSOCIATED
WITH Q-VECTOR DIVERGENCE) MAY LEAD TO SOME BREAKS IN THE CLOUDS OVER
THE WESTERN CWA (ESPECIALLY NEAR THE WISCONSIN BORDER) AND HAVE
TRENDED TOWARDS A MUCH DRIER FORECAST THAN PREVIOUSLY SHOWN DURING
THE AFTERNOON. THAT IDEA FOLLOWS QPF OUTPUT BY THE MODELS FOR
WESTERN UPPER MICHIGAN...BEFORE THE NEXT WAVE APPROACHES AND BRINGS
INCREASING MID LEVEL MOISTURE FOR TONIGHT. IR SATELLITE AND SURFACE
OBS INDICATE A POCKET OF LOW LEVEL MOISTURE OVER NORTHEAST MINNESOTA
AND NORTHWEST ONTARIO THAT IS PRODUCING CEILINGS AT OR BELOW 1KFT.
THIS COMPLICATES THE SKY COVER FORECAST...AS MODELS INDICATE THIS
LOW CLOUD DECK WILL MOVE INTO THE WESTERN U.P. OVER THE NEXT COUPLE
OF HOURS (STARTING TO SEE HINTS OF IT AT KIWD AT 4AM). WILL
CONTINUE TO HAVE THOSE CLOUDS THROUGH MOST OF THE MORNING BEFORE
THE MODELS SHIFT THE MOISTURE NORTHEAST AND INCREASED MIXING
DEVELOPS. EXPECT THIS NORTHEAST MOVEMENT TO PRODUCE SOME PARTLY
CLOUDY SKIES OVER PORTIONS OF SOUTHWEST UPPER MICHIGAN...ESPECIALLY
ALONG THE WISCONSIN BORDER. THE INCREASE IN MIXING TODAY WILL
PRODUCE SOME GUSTY WEST-NORTHWEST WINDS OVER THE WESTERN 2/3RDS OF
THE CWA BEHIND THE TROUGH. TRENDED WINDS UP IN THOSE AREAS DUE TO
BETTER MIXING SHOWN ON 00Z MODEL RUNS. EXPECT SUSTAINED WINDS IN THE
10-15MPH RANGE WITH GUSTS OF 20-25MPH TO MAYBE EVEN 30MPH OVER THE
KEWEENAW PENINSULA. THESE INCREASED WINDS AND SLIGHTLY DRYER LOW
LEVEL AIR SHOULD HELP TO SCOUR OUT ANY REMAINING FOG OVER THE
EASTERN U.P. THIS MORNING. DID LINGER SOME FOG OVER CENTRAL/EASTERN
PORTIONS OF LAKE SUPERIOR...BUT SHOWED A DIMINISHING TREND WITH THE
DRIER WESTERLY FLOW. FINALLY...HIGHS TODAY LOOK TO BE IN THE UPPER
40S TO LOW/MID 50S...WITH THE HIGHEST VALUES NEAR THE WISCONSIN
BORDER UNDER THE EXPECTATIONS OF SOME SUNSHINE IN THE AFTERNOON.
THE SECOND WAVE...CURRENTLY NORTH OF LAKE WINNIPEG...IS EXPECTED
TO IMPACT THE AREA LATE THIS AFTERNOON AND INTO TONIGHT. WITH THE
TRACK OF THE WAVE AND ITS MERGING WITH ENERGY ROUNDING THE UPPER
RIDGE...THERE IS THE POTENTIAL FOR A FEW SHOWERS ALONG THE
WISCONSIN BORDER LATE THIS AFTERNOON AND THROUGH THE EVENING HOURS.
CONFIDENCE IS LOW ON THE RAIN POTENTIAL...DUE TO MID LEVEL Q-VECTOR
DIVERGENCE...AND WITH LIMITED MODEL QPF AMOUNTS...OPTED TO STICK
WITH SLIGHT AND LOW CHANCE POPS. THE OTHER OPPORTUNITY FOR
PRECIPITATION WILL COME LATE TONIGHT AND INTO SUNDAY MORNING. THE
TROUGH THAT SLIDES THROUGH THE AREA THIS MORNING AND EARLY AFTERNOON
WILL BECOME A CLOSED LOW OVER SOUTHEAST ONTARIO AND SWEEP A
SECONDARY TROUGH ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT. BEST
FORCING/MOISTURE OVER NORTHEAST HALF TO THIRD OF THE CWA...CLOSER TO
THE SECONDARY SURFACE TROUGH...SO WILL KEEP CHANCE POPS OVER
NORTHEAST LAKE SUPERIOR AND LIMIT POPS OVER THE LAND AREAS NEAR
LAKE SUPERIOR TO SLIGHT CHANCES. THE LATEST TRENDS IN THE 00Z
MODELS SEEM TO DELAY THE PRECIP TOWARDS SUNDAY MORNING. IF SHOWERS
HAPPEN...DRY LOWER LEVEL AIR WILL LEAD TO COOLING OF THE COLUMN TO
THE WETBULB TEMP. WITH THE WETBULB0 VALUES AROUND
1600-3000FT THIS EVENING BEFORE FALLING TO THE SURFACE FROM
WEST TO EAST OVERNIGHT...EXPECT THE PRECIP TO BE RAIN
INITIALLY...BEFORE TRANSITIONING TO A RAIN/SNOW MIX AND EVENTUALLY
ALL SNOW (AS COLDER AIR ALOFT SLIDES SOUTHEAST OVER THE AREA). A
TIGHTENING GRADIENT AHEAD OF THE SECONDARY TROUGH WILL KEEP A STEADY
WEST TO EVENTUALLY NORTHWEST WIND GOING THROUGH THE NIGHT...WITH THE
STRONGEST WINDS NEAR LAKE SUPERIOR AND OVER THE KEWEENAW PENINSULA
TOWARDS DAYBREAK (GUSTS TO 20-25MPH). LOWS TONIGHT LOOK TO BE IN
THE LOWER 30S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 409 AM EDT SAT MAY 3 2014
NAM SHOWS A BROAD 500 MB RIDGE ACROSS THE PLAINS 12Z SUN WITH A
TROUGH IN THE UPPER GREAT LAKES AND ANOTHER IN THE PACIFIC NW. THE
RIDGE AMPLIFIES WITH TIME SUN INTO MON NIGHT ACROSS THE PLAINS AS
THE TROUGH IN THE PACIFIC NW DIGS INTO THE WESTERN U.S.
LOOKS PRETTY QUIET THIS FORECAST PERIOD WITH RAIN AND SNOW SHOWERS
MOVING OUT ON SUNDAY AND WILL GO DRY SUNDAY NIGHT THROUGH MONDAY
NIGHT. DID LOWER TEMPERATURES A BIT FOR SUNDAY NIGHT WITH RIDGING
ACROSS THE AREA AND CLEAR SKIES AND LIGHT WINDS WOULD ALLOW FOR
IDEAL RADIATIONAL COOLING CONDITIONS TO SET UP. MADE A FEW TWEAKS TO
TEMPERATURES ALONG THE LAKESHORES TO ACCOUNT FOR COOLER LAKE BREEZES
COMING IN OFF THE WATER/ICE AREAS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE ACROSS THE
PLAINS WITH A TROUGH IN THE WESTERN U.S. 12Z TUE. THE RIDGE GETS
AMPLIFIED AS IT MOVES INTO THE UPPER GREAT LAKES 12Z WED WHILE THE
TROUGH DIGS INTO THE ROCKIES WITH FURTHER AMPLIFICATION OF THE
PATTERN FOR 12Z THU AS THE TROUGH MOVES SLOWLY EASTWARD. THE TROUGH
MOVES INTO THE UPPER GREAT LAKES 12Z FRI. AS THE RIDGE POKES UP INTO
THE AREA...TEMPERATURES WILL BEGIN A WARMING TREND THIS FORECAST
PERIOD. GFS AND ECMWF SHOW 850 MB TEMPERATURES UP TO 13C ON THU AND
IF WE WOULD MIX THAT DOWN TO THE SFC...WOULD GET UP INTO THE MID
70S. ONLY PROBLEM IS WARM FRONT IS TO THE SOUTH AND THERE WILL BE
PLENTY OF CLOUDS AROUND SO THOSE TEMPERATURES WILL NOT BE REALIZED.
WITH WARM SECTOR STAYING MOSTLY TO THE SOUTH...HAVING THUNDER IN
THERE FOR WED NIGHT THROUGH THU NIGHT STILL LOOKS GOOD. ALSO LOOKS
LIKE THERE COULD BE SOME HEAVY RAIN AS AREA IS NORTH OF THE WARM
FRONT ALLOWING PLENTY OF MOISTURE TO OVERRUN THE WARM FRONT AND GET
WRUNG OUT OVER THE AREA. TEMPERATURES WILL SLOWLY WARM TO NEAR
NORMAL TOWARDS THE END OF THE FORECAST PERIOD. DID GO WITH HIGHER
POPS FOR WED NIGHT THROUGH THU NIGHT WITH WARM FRONT ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 202 PM EDT SAT MAY 3 2014
BREEZY CONDITIONS WILL LINGER THROUGH THE REMAINDER OF THE AFTERNOON
HOURS. EXPECT THE NEXT DISTURBANCE WILL APPROACH THE AREA LATE THIS
AFTERNOON AND TONIGHT. KIWD HAS THE BEST OPPORTUNITY FOR SHOWERS.
THE PRECIPITATION WILL LIKELY START AS RAIN...BUT IF IT IS STILL
OCCURRING OVERNIGHT IT WILL CHANGE TO SNOW. VFR TO MVFR CEILINGS
WILL BE POSSIBLE...AT CMX AND SAW FROM AROUND 09Z-15Z SUNDAY THANKS
TO UPSLOPE ENHANCEMENT OF THE NW WINDS BECOMING MORE N THROUGH THE
MORNING /PARTICULARLY AT SAW/. OTHERWISE...VFR CEILING AND VIS
SHOULD RETURN BY MID-LATE MORNING AS GUSTS IN THE 15-20KT RANGE
RETURN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT SAT MAY 3 2014
A LOW PRESSURE TROUGH...STRETCHING SOUTHWEST FROM A PARENT LOW OVER
SOUTHERN HUDSON BAY...WILL SHIFT EAST ACROSS LAKE SUPERIOR THIS
MORNING THROUGH THE FIRST HALF OF THE AFTERNOON. AS THIS TROUGH
SHIFTS THROUGH...WINDS WILL VEER TO THE WEST AT 10-25KTS. AS THE
FIRST TROUGH CONTINUES EAST TONIGHT...A SECONDARY TROUGH WILL SLIDE
ACROSS EASTERN LAKE SUPERIOR LATE TONIGHT INTO SUNDAY
MORNING...TURNING WINDS TO THE NORTHWEST AND REMAINING IN THE
10-25KT RANGE. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE SOUTHEAST
OVER THE UPPER GREAT LAKES REGION SUNDAY AFTERNOON AND REMAIN
THROUGH TUESDAY...KEEPING WINDS BELOW 15KTS. A LOW PRESSURE SYSTEM
LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS ON WEDNESDAY WILL LEAD
TO INCREASING SOUTHEASTERLY WINDS...BUT THEY SHOULD REMAIN BELOW
25KTS.
&&
.HYDROLOGY...
ISSUED AT 427 AM EDT SAT MAY 3 2014
STREAMS AND RIVERS WILL CONTINUE TO EXPERIENCE HIGHER LEVELS.
LOCATIONS STILL NEAR OR ABOVE BANKFULL AT THIS TIME INCLUDE THE
STURGEON RIVER OVER HOUGHTON AND BARAGA COUNTIES...THE PAINT RIVER
NEAR CRYSTAL FALLS...THE STURGEON RIVER NEAR NAHMA JUNCTION AND
TAHQUAMENON RIVER NEAR PARADISE.
RIVERS OVER EASTERN UPPER MICHIGAN HAVE STARTED TO STEADY OUT
ON THEIR RISES OVER THE LAST 12 HOURS...SINCE THE HEAVIER
PRECIPITATION SEEN IN THAT AREA WEDNESDAY INTO THURSDAY HAS BEEN
WORKING THROUGH THE BASINS. WITH ONLY LIGHT RAIN EXPECTED TODAY
(GENERALLY UNDER 0.15INCH)...EXPECT THOSE RIVERS LEVELS TO BE STEADY
OR SLOWLY FALL TODAY AND INTO THE FIRST PART OF NEXT WEEK. ONE
INTERESTING ITEM TO NOTE IS THAT THE TAHQUAMENON RIVER NEAR
PARADISE IS CURRENTLY AT 9.57 FEET...WHICH IS THE 3RD HIGHEST LEVEL
ON RECORD /60 YEARS OF DATA/.
WITH A FEW INCHES OF SNOW WATER EQUIVALENT UPSTREAM OF THE STURGEON
RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK RIVER...THE
ONGOING SNOW MELT WILL CONTINUE TO FEED WATER INTO THEIR BASINS
EVEN WITH LIGHTER RAINFALL EXPECTED THROUGH SUNDAY MORNING. EXPECT
MULTIPLE DAYS WITH TEMPS IN THE 40S AND 50S THOUGH THE MIDDLE OF
NEXT WEEK TO MELT THE REMAINING SNOW. THE MELT WILL BE SLOWED DOWN
THOUGH AS NIGHTTIME TEMPS WILL STILL BE IN THE LOWER TO MIDDLE 30S.
AFTER THE RAIN THROUGH THE SUNDAY MORNING...THE NEXT CHANCE
OF WIDESPREAD RAINFALL WILL NOT OCCUR UNTIL NEXT WEDNESDAY OR
THURSDAY. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS SHOULD
CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KF
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
127 PM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SAT MAY 3 2014
WATER VAPOR IMAGERY OVERLAYED WITH A RAP H5 ANALYSIS SHOWS A
RATHER EXPANSIVE UPPER LOW SPINNING TO THE SW OF HUDSON BAY WITH
AN UPPER RIDGE OVER THE ROCKIES BEGINNING TO GET FLATTENED OUT BY
AN UPPER LOW APPROACHING THE WASHINGTON/BC COAST. OUR LOCATION
BETWEEN THE HUDSON UPPER LOW AND WESTERN RIDGE HAS PLACED STRONG
NORTHWEST MID AND UPPER LEVEL JETTING ACROSS THE UPPER MIDWEST.
THIS JETTING IS IN PLACE IN RESPONSE TO A STRONG MID LEVEL THERMAL
GRADIENT THAT IS IN PLACE BETWEEN THESE TWO FEATURES AS WELL. THIS
TYPE OF WEATHER PATTERN WILL SUPPLY US WITH PLENTY OF MID AND
UPPER LEVEL CLOUD COVER THROUGH THE DAY TODAY...THAT WILL START TO
CLEAR OUT FOR ALL BUT THE SOUTHWEST TONIGHT.
BIGGEST ISSUE FOR PRECIP THIS PERIOD WILL BE LACK OF LOW LEVEL
MOISTURE...HOWEVER THERE STILL LOOKS TO BE A COUPLE OF SHOTS FOR
PRECIP. THIS FIRST WILL COME THIS AFTERNOON AND IS ASSOCIATED WITH
CLOUD COVER AND SPRINKLES OVER NW MN. THE MPX AND SPC WRFS ALONG
WITH MEMBERS 1 AND 3 OF THE HOPWRF ALL SHOW THE ADDITION OF DAYTIME
HEATING LEADING TO THE DEVELOPMENT OF ISO-SCT SHOWERS ALONG AND
EAST OF THE MISSISSIPPI RIVER...SO PULLED THE EXISTING 20 POP WE
HAD SOUTHWEST TO JUST WEST/SOUTH OF THE MS RIVER. LOOKING AT MIXED
LAYER DEWPOINTS FROM THE GFS/NAM...A RIBBON OF HIGHER MOISTURE
LOOKS TO HANG BACK ALONG THIS AXIS...ALLOWING FOR THE DEVELOPMENT
OF DIURNAL SHOWERS.
THE SECOND AND BETTER CHANCE OF PRECIP ARRIVES LATE TONIGHT AS A
ZONE OF STRONG FGEN IN THE H7-H6 LAYER ALONG WITH ISENTROPIC
UPGLIDE ON THE 305K SFC SENDS A BAND OF PRECIP FROM THE CENTRAL
ND/SD BORDER SOUTHEAST INTO NORTH CENTRAL IOWA. BY THE END OF THE
SHORT TERM...WE HAVE LIKELY POPS SHOWING UP SOUTH OF THE MN RIVER
IN ASSOCIATION WITH THIS FORCING. THE ONLY MODEL THAT DOES NOT
REALLY AGREE WITH THIS SCENARIO IS THE GFS. ALTHOUGH IT HAS THE
FGEN/ISENTROPIC FORCING...IT DOES NOT PRODUCE ANY QPF. QUICK LOOK
AT SOME RH TIME-HEIGHT CROSS SECTIONS SHOWS THE PROBLEM...THE GFS
NEVER SATURATES THE ATMO BELOW H8. GIVEN THE STRENGTH OF THE
FORCING...TEND TO BELIEVE PRECIP GENERATED WILL BE STRONG ENOUGH
TO OVERCOME THE DRY AIR SO FAVORED A NON-GFS FORECAST FOR THIS
PRECIP LATE TONIGHT.
TEMPERATURES TODAY WILL BE SIMILAR TO WHAT WAS SEEN FRIDAY AS WE
LOOK TO MIX UP TO AROUND 775 MB. ALSO SIMILAR TO YESTERDAY WILL BE
THE BREEZY CONDITIONS...THOUGH NORTHWEST WINDS WILL NOT BE QUITE
AS STRONG AS WHAT WE SAW FRIDAY OUT IN WESTERN MN. TONIGHT...
EXTENT OF CLOUD COVER WILL PLAY A LARGE ROLL IN WHERE TEMPERATURES
END UP SETTLING TO. IN THE SOUTHWEST...MAINLY CLOUDY SKIES WILL
HOLD TEMPS UP AROUND 40...BUT MOSTLY CLEAR SKIES IN THE NORTHEAST
CWA WILL ALLOW TEMPERATURES TO FALL BACK TO AROUND 30 WITH THE
PROBABILITY OF A FREEZE STEADILY INCREASING THE FARTHER NORTHEAST
YOU GET FROM I-94. AT THIS POINT...WE ARE STILL EARLY ENOUGH IN
THE GROWING SEASON NORTH OF I-94 THAT NO FROST/FREEZE PRODUCTS ARE
NECESSARY YET.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 345 AM CDT SAT MAY 3 2014
SUNDAY THROUGH TUESDAY...A FAIRLY BENIGN PATTERN WILL PERSIST FOR
THE EARLY PORTION OF THE UPCOMING WEEK DUE TO GENERALLY UPR LVL
RIDGING OVER THE CENTRAL CONUS WITH WEAK SFC PRES PATTERNS ACRS
THE REGION. SEVERAL WEAK UPR LVL DISTURBANCES WILL RIDE THE
PERIPHERY OF THE RIDGE THRU THE REGION...MAINLY LATE SUN MRNG AND
LATE SUN NIGHT...AND AFFECTING MAINLY W AND S MN WITH OCNL SHWRS
AND POSSIBLY AN ISOLD TSTM. NOT LOOKING FOR MUCH IN THE WAY OF QPF
SINCE DEEP MOISTURE IS FAIRLY CONFINED AND UPR LVL SUPPORT IS WEAK
AT BEST. DID SHOW POPS INTO THE UPR CHC AND LOW-END LIKELY RANGE
SUN MRNG DUE TO MODEL CONSISTENCY...BUT CONFIDENCE DROPS FOR SUN
NIGHT SO ONLY USED LOW-MID CHC RANGE. TEMPS WILL START A GRADUAL
WARMING TREND DURG THIS PERIOD...ESP BY TUE AS THE RIDGE IS FAIRLY
ESTABLISHED AND SLY WINDS BECOME MORE PROMINENT.
WEDNESDAY THROUGH FRIDAY...A MORE ACTIVE PATTERN IS EXPECTED AS A
LARGE UPR LVL TROF MOVING ONSHORE THE CALI COAST...SHIFTING SWD
FROM THE GULF OF ALASKA...INTERACTS WITH A DEVELOPING LOW PRES
CENTER OVER THE CO/KS REGION DURG THE DAY ON WED. AS THE LARGE
TROF DRAGS MOISTURE WITH IT FROM THE PACIFIC INTO THE CENTRAL
CONUS...AND HELPS INTENSIFY THE LOW PRES CENTER...THESE FEATURES
WILL ALL STREAM INTO THE MID-TO-UPR MISSISSIPPI RIVER VALLEY WED
INTO THU...PRODUCING PERIODS OF SCATTERED SHWRS/TSTMS FOR THE AREA
TUE NIGHT THRU THU NIGHT. THERE IS STILL MUCH UNCERTAINTY WITH
RESPECT TO THE TRACK OF THE SYSTEM AND HOW MUCH DRY AIR BECOMES
ENTRAINED INTO THE SYSTEM. THIS WILL AFFECT NOT ONLY QPF AMOUNTS
BUT ALSO THE POTENTIAL FOR ANY SEVERE WX SINCE INSTABILITY WILL BE
HIGHLY DEPENDENT ON HOW MUCH WARM-SECTORING CAN OCCUR AND IF
HIGHER LOW-LEVEL MOISTURE /DEWPOINTS/ ARE ADVECTED NWD ALONG WITH
WARMER AIR. HAVE MAINTAINED TSTM MENTION FOR THE ENTIRE CWFA.
TEMPS DO CONTINUE THEIR WARMING TREND MID-TO-LATE WEEK WITH THE
ENTIRE CWFA HAVING HIGHS CLIMB TO THE MID 60S...AND POSSIBLY INTO
THE LOWER 70S NEAR I-90.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1247 PM CDT SAT MAY 3 2014
CONSISTENT NORTHWEST FLOW TODAY WILL CONTINUE TO PRODUCE GUSTY
CONDITIONS ACROSS THE AREA THIS AFTERNOON. MODEL SOUNDINGS
INDICATE DEEP MIXING ABOVE 800MB WHICH IS MIXING DOWN THE STRONG
NORTHWEST FLOW. THE BREEZY CONDITIONS CAN BE EXPECTED TO CONTINUE
UNTIL WE CAN BEGIN TO COOL THE SURFACE AND DECOUPLE THE WINDS
ALOFT FROM THE SURFACE. SHORT RANGE HI RES MODELS INCLUDING THE
HRRR CONTINUE TO SHOW SCATTERED SHOWER DEVELOPMENT THIS AFTERNOON.
AS PREVIOUS FORECAST MENTIONED...THIS STILL APPEARS OVERDONE SO
DID NOT PUT RAIN AT ANY TAF SITES...BUT KEPT VCSH AT THE WISCONSIN
SITES AS THAT STILL LOOKS LIKE A POSSIBILITY. WINDS WILL BE MUCH
LIGHTER TOMORROW AND JUST MID CLOUD COVER IS POSSIBLE...SO VFR IS
EXPECTED THROUGH THE PERIOD AT ALL SITES. RAIN WILL DEVELOP ACROSS
FAR SOUTHWESTERN MINNESOTA SO WENT WITH A MENTION OF VCSH AFTER
13Z TOMORROW.
KMSP...AS MENTIONED ABOVE...DID NOT MENTION RAIN IN THE TAF...BUT
BE AWARE THERE MAY BE SOME SCATTERED SHOWERS THIS
AFTERNOON...ALTHOUGH LATEST RADAR TRENDS ARE VERY QUIET. OTHERWISE
VFR EXPECTED.
/OUTLOOK FOR KMSP/
SUN...VFR. WINDS NE 5 KTS.
MON...VFR. WINDS E 5-10 KTS.
TUE...VFR. WINDS ESE 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JPC
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
346 PM CDT SAT MAY 3 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 330 PM CDT SAT MAY 3 2014
THE MAIN FORECAST CONCERNS THROUGH THE SHORT TERM WILL BE
TEMPERATURES...THEN SMALL PRECIPITATION CHANCES TONIGHT AND EARLY
SUNDAY...LATE SUNDAY NIGHT AND ALSO TUESDAY.
THIS MORNING/S UPPER AIR MAPS SHOWED A CLOSED H5 LOW PRESSURE SYSTEM
APPROACHING THE PACIFIC NORTHWEST WITH 100M+ HT FALLS. A NARROW
RIDGE EXTENDED FROM WESTERN MONTANA TOWARD ARIZONA. CLOSED H5 LOW
PRESSURE WAS ALSO CENTERED OVER MANITOBA WITH IT/S TROF STRETCHING
SOUTHEAST INTO THE GREAT LAKES AND MID ATLANTIC STATES. THIS MID
LEVEL TROF HAS RESULTED IN A PUSH OF THE SURFACE FRONT TO SOUTH OF
MANHATTAN KS TOWARD EMPORIA AND SOUTH OF HAYS KS. THERE WAS
NORTHWEST FLOW ALOFT OVER THE PLAINS AND A RIBBON OF MOISTURE WAS
NOTED AT THE MID LEVELS AND ALSO AT H85 ACROSS WESTERN SD AND
WESTERN NEBRASKA. MID LEVEL WARM AIR ADVECTION AND FRONTOGENESIS
ALONG WITH STEEP LAPSE RATES RESULTED IN A SMALL AREA OF
SHOWERS/SPRINKLES FROM SD INTO NEBRASKA AND WESTERN IOWA.
THROUGH THE SHORT TERM...THERE WILL BE THESE SUBTLE FEATURES THAT
WILL BRING SOME PRECIP CHANCES TO THE AREA...HOWEVER ANY
WIDESPREAD PRECIPITATION LOOKS TO HOLD OFF UNTIL LATER IN THE
WEEK.
WARMER AIR WILL BE LIFTING NORTHWARD LATER THIS AFTERNOON
AND TONIGHT WITH STRENGTHENING H85 WINDS AND SOME MOISTURE ALONG
AND NORTH OF THE H85 WARM FRONT. MEANWHILE...FRONTOGENESIS
INCREASES AS WELL NEAR THE SD/NEBRASKA BORDERS. SOME OF THE SHORT
RANGE HIGH RES MODELS SHOW ECHOES ALOFT IN SOUTHEAST NEBRASKA AS
EARLY AS LATE THIS AFTERNOON. THE RAP AND 4KM WRF HAVE PRECIP
DEVELOPING IN NORTHEAST NEBRASKA AFTER 09Z...THE NAM BETWEEN 06Z-
09...AND THE GFS BETWEEN 06Z-12Z. ALTHOUGH THERE MAY BE SOME
SPRINKLES OR ISOLATED SHOWERS FARTHER SOUTH...HOWEVER DUE TO LOW
CONFIDENCE...HAVE ONLY MAINTAINED ISOLATED SHOWERS AND A POSSIBLE
RUMBLE OF THUNDER FOR NORTHEAST NEBRASKA BETWEEN 06Z AND 12Z. SOME
OF THESE SHOWERS MAY LINGER IN THE NORTHEAST SUNDAY MORNING.
SUNDAY...THE SURFACE FRONT WILL STILL BE TO THE SOUTH OF THE
FORECAST AREA WITH A BRISK EAST SURFACE FLOW. THIS SHOULD HOLD
TEMPERATURES IN THE 60S...WITH 70S FOR SOUTHEAST NEBRASKA.
TEMPERATURES NEAR THE KS BORDER WILL NEED TO BE MONITORED DUE TO
THE FRONT NEARBY. THERE IS SOME WEAK LIFT...HOWEVER MOISTURE
APPEARS LIMITED...THUS HAVE LEFT DRY. SUNDAY NIGHT...ANOTHER WEAK
SHORTWAVE PASS THROUGH THE NORTHWEST FLOW ALOFT AND AGAIN...THERE
MAY BE ISOLATED SHOWERS...HOWEVER THE COVERAGE IS TOO LOW TO
MENTION AT THIS TIME. THE FLOW ALOFT TRANSITIONS TO SOUTHWEST FLOW
AND A WEAK IMPULSE COULD BRING ISOLATED SHOWERS TUESDAY. WARM MID
LEVEL TEMPERATURES ARE IN PLACE AND THE CURRENT FORECAST IS
DRY...HOWEVER THIS WILL NEED TO BE WATCHED AS INSTABILITY
INCREASES.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 PM CDT SAT MAY 3 2014
STILL SOME SIGNIFICANT MODEL DIFFERENCES FOR TEMPERATURES WED.
TRENDED WITH THE EC THAT HAS THE HOTTER TEMPERATURES ACROSS THE
SOUTHERN PART OF THE FORECAST ARE COMPARED TO THE COOLER GFS.
SHOWER AND THUNDERSTORM CHANCES INCREASE FOR WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT WITH MUCH DEEPER MOISTURE RETURNING TO THE
REGION...A SURFACE FRONT IN THE AREA AND THE LONG WAVE TROF MOVING
TO THE PLAINS. NUDGED RAIN CHANCES UP FOR THURSDAY/THURSDAY NIGHT.SHEAR
AND INSTABILITY INCREASE...HOWEVER FRONTAL PLACEMENT FOR THURSDAY
WILL BE A KEY FACTOR FOR SEVERE WEATHER POTENTIAL
THURSDAY/THURSDAY NIGHT. SOME ENERGY MAY LAG AND MAY HAVE TO
INCLUDE PRECIP CHANCES INTO FRIDAY...BUT FOR NOW FRI/SAT ARE DRY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1255 PM CDT SAT MAY 3 2014
VFR CONDITIONS ARE FORECAST TO PREVAIL AT KOFK...KOMA...AND KLNK
THROUGHOUT THE FORECAST PERIOD. SOME LOW LEVEL WINDSHEAR POSSIBLE
AT KLNK AND KOMA AFTER 10Z SUNDAY DUE TO MODERATELY STRONG
SOUTHWEST WINDS ALOFT AND EASTERLY WINDS AT THE SURFACE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1235 PM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT SAT MAY 3 2014
A FEW SPRINKLES ARE ONGOING THIS MORNING AND THE RAP MODEL
INDICATES SOME VERY WEAK MIDLEVEL FRONTOGENESIS AT THE 700-500MB
LEVEL. THIS RAIN IS INDICATIVE OF MOISTURE POOLING IN THE
NORTHWEST FLOW ALOFT AND...FOR NOW...WILL BE DISCOUNTED AS
INSIGNIFICANT.
THE RAP AND OTHER MODELS SHOW K INDICES INCREASING TO 30 TO 35C
LATE THIS AFTERNOON AND THIS EVENING ACROSS WRN NEB. THE RAP EVEN
SHOWS SOME LIFT IN THIS MOISTURE POOL AT 00Z THIS EVENING. SO
FOLLOWING THE 00Z NAM...ISOLATED SHOWERS AND THUNDERSTORMS ARE IN
THE FORECAST THIS EVENING ACROSS THE PANHANDLE AND THE WRN
SANDHILLS. ANYTHING THAT FORMS SHOULD MOVE EAST AND DECAY AROUND
03Z-06Z.
THE MODEL CONSENSUS ALSO SHOWS ISOLATED SHOWERS AND THUNDERSTORMS
WORKING INTO THE NERN ZONES TONIGHT. THE NAM SHOWS STRONG
MIDLEVEL FRONTOGENESIS ALONG AND JUST NORTH OF THE MISSOURI RIVER
SUPPORTING THIS RAIN.
HIGHS TODAY...FROM NEAR 70 IN THE NORTHEAST TO LOWER 80S
SOUTHWEST IS BASED ON A MULTI-MODEL APPROACH. THE MODELS ARE
TIGHTLY CLUSTERED AROUND 80F AT NORTH PLATTE THIS AFTERNOON. LOWS
TONIGHT FALL INTO THE 40S. A STATIONARY FRONT WILL SETTLE INTO
THE NORTH PLATTE VALLEY AND THIS SHOULD KEEP THE ATMOSPHERE WELL
MIXED WITH LOWS IN THE UPPER 40S ACROSS SRN NEB.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 316 AM CDT SAT MAY 3 2014
LOW AMPLIFIED UPPER LEVEL RIDGE ACROSS THE SOUTHERN PLAINS WITH
NEARLY ZONAL FLOW FOR THE HIGH PLAINS ON SUNDAY. LEE SIDE TROUGH
ALONG THE FRONT RANGE WITH A COLD FRONT STALLING FROM THE HILLS
INTO N CENTRAL KS. DECENT TEMPERATURE SPREAD ACROSS THE CWA WITH
MID 60S ACROSS MUCH OF N CENTRAL NEB...WHILE FAR SW NEB WARMS
INTO THE UPPER 80S. MODELS ARE WAVERING SLIGHTLY WITH THE SW PUSH
OF THE COLD AIR...WITH SOME UNCERTAINTY TO TEMPS ACROSS THE CWA.
A LIGHT MOVEMENT EITHER WAY COULD CAUSE A 10 PLUS DIFFERENCE IN
TEMPS. ONE THING WITH HIGHER CONFIDENCE IS THE DRY AIR IN PLACE
AND PARTLY TO MOSTLY SUNNY SKIES.
BY MONDAY PACIFIC LOW WILL PUSH ONSHORE...INTO THE PACIFIC NW.
THE QUASI-STATIONARY SFC FRONT WILL STILL BE ACROSS THE AREA.
SUNNY TO MOSTLY SUNNY SKIES WILL HELP TO WARM N CENTRAL TO OR A
FEW DEGREES WARMER THAN SUNDAY. THE RIDGE AXIS IS SLIGHTLY
FURTHER EAST SO DID NOT TAKE HIGHS QUITE AS WARM IN THE SW. BY
MONDAY EVENING A WEAK DISTURBANCE WILL DRIFT EAST ACROSS S DAKOTA
AND MAY TAP PORTIONS OF NORTHERN NEB. FOR NOW HAVE LOW POPS IN
THE HIGHER TERRAIN WHERE CLOUD BASES A LITTLE LOWER AND A BETTER
CHANCE FOR ANY DEVELOPMENT TO MAKE IT THROUGH THE DRY BL.
TUESDAY WILL BE THE START OF A MORE ACTIVE PERIOD. THE PACIFIC NW
TROUGH WILL SLOWLY DIG TOWARDS THE 4 CORNERS BY THURSDAY. A
COUPLE OF MID LEVEL SHORT WAVES EJECT OVER THE AREA AHEAD OF THE
MAIN LOW. EACH WAVE WILL BRING THE CHANCE FOR STORMS. STRONG CAP
WITH LIMITED MOISTURE SO SOME CONCERNS TO HOW WIDESPREAD ANY
ACTIVITY WILL BE AND KEPT POPS AT OR LESS THAN 50 PERCENT.
MEANWHILE THE RIDGE AXIS SHIFTS EAST WITH TEMPS COOLING FROM THE
NW.
THEN FOR WED AND THURS...WITH A BETTER CHANCE FOR PRECIP EXPECTED
AND AT LEAST MORE CLOUDINESS...HAVE HIGHS IN THE UPPER 50 TO
LOWER 70S...WARMEST IN THE SOUTH. MOISTURE IS STILL A CONCERN AS
BEST MOISTURE GETS TURNED TO THE NE BEFORE MAKING IT TO THE CWA.
MODELS ARE IN BETTER AGREEMENT WITH TROUGH AXIS TO QUICKLY EJECT
ACROSS THE PLAINS ON FRIDAY AND FRIDAY NIGHT. DRY SLOT MAY PLAY
INTO THE AREA PENDING THE EXACT TRACK OF THE LOW...WHICH IS STILL
UP IN THE AIR. CURRENT THOUGH IS MORE DRY SLOT THAN NOT AND
SHOULD SEE HIGHS BACK INTO THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1233 PM CDT SAT MAY 3 2014
A PARTLY TO MOSTLY CLEAR SKY WILL REMAIN SATURDAY FOR WESTERN
NEBRASKA. AN AREA OF LOW PRESSURE IN EASTERN COLORADO WILL BRING
SOUTHEASTERLY TO EASTERLY WINDS THROUGH THE TAF FORECAST PERIOD. THE
WIND WILL PICK UP A BIT SUNDAY MORNING...MAINLY FOR KVTN. OTHER THAN
SOME GUSTY WINDS...THERE ARE NO OTHER CONCERNS AS VFR CONDITIONS
CONTINUE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...DS/TAYLOR
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1050 AM PDT SAT MAY 3 2014
.DISCUSSION...A LARGE UPPER LOW WILL BRING HIGH AND MID LEVEL
CLOUDS FOR MOST INLAND LOCATIONS AND A LOWER DECK WILL PERSIST AT
THE COAST. THE 12Z NAM AND RAP KEEP MOST PRECIPITATION TODAY
CONFINED TO THE NORTH COAST, EVEN THEN IT`S PROBABLY NOT GOING TO
AMOUNT TO MUCH IF ANYTHING. ELSEWHERE IT WILL BE DRY AND COOLER
COMPARED TO YESTERDAY. GUSTY WINDS ARE EXPECTED EAST OF THE
CASCADES, BUT THEY ARE NOT EXPECTED TO REACH ADVISORY CRITERIA.
-PETRUCELLI
&&
.AVIATION...BASED ON THE 03/18Z TAF CYCLE. VFR CONDITIONS ARE
EXPECTED TO BE THE PREDOMINATE CONDITION TODAY. HOWEVER BRIEF MVFR
CIGS ARE POSSIBLE ALONG THE COAST THIS MORNING. THE MAIN CONCERN
WILL BE GUSTY WINDS EAST OF THE CASCADES LATE THIS MORNING THROUGH
THE AFTERNOON. CIGS WILL LOWER TO MVFR WEST OF THE CASCADES TONIGHT
AS A COLD FRONT MOVES INLAND. VFR CONDITIONS WILL CONTINUE EAST OF
THE CASCADES THROUGH TONIGHT. -SVEN
&&
.MARINE...UPDATED 03/1030 PDT...CONDITIONS WILL BE HAZARDOUS TO
SMALL CRAFT THIS THROUGH SUNDAY. A COLD FRONT OFFSHORE WILL ALLOW
SOUTH WINDS TO INCREASE TO 15 TO 30 KT TODAY. WESTERLY SWELL WILL
ALSO INCREASE AND COMBINE WITH STEEP WIND GENERATED WAVES. SEAS PEAK
AT 12 TO 15 FEET ACROSS THE NORTH TONIGHT, WITH SLIGHTLY LOWER SEA
HEIGHTS IN THE SOUTH. MODERATE RAIN WILL ACCOMPANY THE FRONTAL
PASSAGE TONIGHT, THEN BECOME MORE SHOWERY SUNDAY AND MONDAY. SEAS
WILL EVENTUALLY EASE BELOW 10 FEET SUNDAY NIGHT AND LOWER FURTHER
EARLY NEXT WEEK. ANOTHER FRONT MAY BRING A BRIEF PERIOD OF SIMILARLY
STRONG SOUTH WINDS TO THE NORTHERN PORTION OF THE WATERS ON
THURSDAY.
&&
.PREV DISCUSSION... /ISSUED 522 AM PDT SAT MAY 3 2014/
DISCUSSION...A LARGE UPPER LOW CONTINUES TO CHURN OFFSHORE
BETWEEN 130W AND 140W THIS MORNING. IT IS CLOSE ENOUGH TO HAVE
PRODUCED A DECENT MARINE PUSH WITH AT LEAST A BROKEN DECK OF LOW
AND MID CLOUD ALL THE WAY TO THE CASCADES NOW, BUT NOT CLOSE
ENOUGH TO BE MUCH OF A THREAT FOR PRECIPITATION. AT LEAST FOR
TODAY, THE CHANCE FOR RAIN IS MAINLY ALONG THE COAST AND OVER THE
WATERS, AND EVEN THAT IS JUST A SLIGHT CHANCE. INLAND, WE`LL SEE
ANOTHER DRY DAY WITH CLOUDS BREAKING UP LATER THIS MORNING.
TEMPERATURES WILL BE QUITE A BIT COOLER THAN WE`VE SEEN THE LAST
FEW DAYS WITH HIGHS ONLY 60S AND LOW 70S.
THE CENTER OF THE TROUGH WILL MOVE TOWARD NW OREGON AND WASHINGTON
ON SUNDAY, BUT ENOUGH ENERGY WILL MOVE THROUGH THE BASE TO PUSH A
COLD FRONT INTO SW OREGON. THE ENTIRE WEST SIDE AND MOUNTAINS WILL
LIKELY SEE RAINFALL AT SOME POINT WITH THE FRONT, BUT AS USUAL IT
WILL TAKE SOME TIME TO GET INTO THE ROGUE VALLEY. RAINFALL WILL BE
MUCH SPOTTIER ON THE EAST SIDE AND IN NORTHERN CALIFORNIA ON
SUNDAY, BUT IT DOES LOOK RATHER BREEZY IN THE AFTERNOON IN THE
USUAL SPOTS.
THE UPPER TROUGH AXIS THEN SWINGS THROUGH MONDAY AND TUESDAY AND
THIS WILL BE A SHOWERY, COOL PERIOD OVER OUR ENTIRE AREA. THERE IS
ENOUGH INSTABILITY WITH THE COLD POOL MONDAY EVENING, THAT WE
COULD SEE SOME LIGHTNING AS WELL.
NO CHANGES WERE MADE TO THE EXTENDED FORECAST THIS MORNING. A WEAK
RIDGE WILL BUILD OFF THE COAST MID NEXT WEEK AND THIS WOULD BE A
DRY PATTERN. HOWEVER, THE MODELS DO HINT AT CLOUDS AND RAIN
SPILLING OVER THE RIDGE INTO THE PACNW. TO WHAT DEGREE THIS
AFFECTS US WILL BE A FUNCTION OF THE STRENGTH OF THE RIDGE. WE`VE
GOT SLIGHT CHANCE POPS GOING AND I SEE NO REASON TO MEDDLE WITH
IT. BY THE END OF THE WEEK AND NEXT WEEK, ALL THE MODELS SUGGEST
THAT THE RIDGE BREAKS DOWN OR AT LEAST WEAKENS ENOUGH TO ALLOW
RAINFALL BACK INTO THE REGION. THIS WOULD, OF COURSE, BE FOCUSED
ON THE WEST SIDE, AND THAT IS WHERE THE HIGHEST POPS CURRENTLY
RESIDE IN OUR FORECAST. -WRIGHT
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 2 PM
THIS AFTERNOON TO 5 PM PDT SUNDAY FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT SUNDAY
FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT MONDAY
FOR PZZ350-370.
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 AM CDT SAT MAY 3 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 235 AM CDT SAT MAY 3 2014
CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A DEEP UPPER LOW JUST OFF THE PACIFIC NORTHWEST COAST...
RIDGING ENCOMPASSING MUCH OF THE WESTERN U.S....AN UPPER LOW OVER
LAKE WINNIPEG AND A SHORTWAVE TROUGH IN EASTERN WI. SUBSIDENCE
AND DRYING IN THE WAKE OF THIS SHORTWAVE TROUGH...AS SEEN FROM 00Z
MPX AND ABR SOUNDINGS AS WELL AS 11-3.9UM IMAGERY AND SURFACE
OBSERVATIONS...HAS RESULTED IN CLEARING SKIES ACROSS THE FORECAST
AREA. HAVE SEEN SOME SPOTTY FOG FORM ACROSS WI AS A RESULT OF THE
RECENT RAIN...CLEARING AND LIGHT WINDS. WEST OF THE MS RIVER
PLENTY OF MIXING EXISTS TO KEEP FOG FROM FORMING. UPSTREAM...MORE
CLOUDS WERE SPREADING OUT OF THE NORTHERN PLAINS AND MANITOBA INTO
MINNESOTA...AHEAD OF THE LAKE WINNIPEG UPPER LOW. NO PRECIPITATION
WAS FALLING OUT OF THESE...THOUGH. DESPITE THE PASSAGE OF A COLD
FRONT LAST EVENING...AIRMASS CONTINUES TO GRADUALLY MODIFY ACROSS
THE UPPER MIDWEST. 925MB TEMPS AT 00Z RANGED FROM 8-10C ACROSS THE
FORECAST AREA TO 10-13C OVER THE NORTHERN PLAINS.
ATTENTION FOR THE SHORT TERM IS MOSTLY ON THE LAKE WINNIPEG UPPER
LOW...AND A 110 KT UPPER JET STREAK ON ITS SOUTHWEST SIDE. MODELS
ARE IN GOOD AGREEMENT TRACKING THE UPPER LOW ACROSS LAKE SUPERIOR
TONIGHT...WHICH MEANS THE UPPER JET STREAK TRAVELS ACROSS NORTHERN
PORTIONS OF MN AND WI. THROUGH ABOUT 06Z SUNDAY...MUCH OF THE
FORECAST AREA ENDS UP IN THE RIGHT EXIT REGION...MAINTAINING
SUBSIDENCE. DESPITE BEING IN THE RIGHT EXIT REGION TODAY...THE
03.00Z GFS PRODUCES LIGHT QPF ACROSS MUCH OF WISCONSIN...WHILE THE
03.00Z SPCWRF-NMM PRODUCES SHOWER ACTIVITY ACROSS MUCH OF THE
FORECAST AREA LATE THIS AFTERNOON INTO THIS EVENING. 03.00Z GFS/NAM
AND LATEST RAP MODEL SOUNDINGS ALL DEPICT LESS THAN 100 J/KG OF CAPE
DEVELOPING THIS AFTERNOON BELOW THE SUBSIDENCE PRODUCED BY THE RIGHT
EXIT REGION...WITH A COLD FRONT COMING THROUGH TO AID IN DEVELOPMENT
OF SHOWERS. THERE ARE ALSO SUGGESTIONS OF A WEAK MID-LEVEL
FRONTOGENETIC ZONE ACROSS SOUTHERN MN...NORTHERN IA AND FAR
SOUTHWEST WISCONSIN AT 00Z TO AID IN SHOWER DEVELOPMENT. BASED ON
THE ABOVE...HAVE DECIDED TO EXPAND THE MENTION OF SHOWERS THROUGH
MUCH OF THE AREA THIS AFTERNOON INTO EARLY THIS EVENING. LOSS OF
DIURNAL HEATING SHOULD CAUSE SHOWERS TO WEAKEN LATE IN THE EVENING.
AS WE APPROACH 12Z SUNDAY...MUCH OF THE FORECAST AREA ENDS UP IN THE
RIGHT ENTRANCE REGION...ALONG WITH STRENGTHENING LOW TO MID LEVEL
FRONTOGENESIS. THESE FORCING FEATURES SHOULD ALLOW FOR A BAND OF
RAIN TO DEVELOP OVER SOUTHERN MN AND NORTHERN IA. FOR SOME REASON
THE 03.00Z GFS IS THE ONLY MODEL NOT PRODUCING QPF OR MUCH
LIFT...DESPITE HAVE A DECENT FRONTOGENETIC SIGNAL. MEANWHILE...THE
REGIONAL CANADIAN...NAM AND ECMWF ALL DEPICT A BAND OF RAIN ALONG
THE MN/IA BORDER 09-12Z SUNDAY. HAVE DISCOUNTED THE GFS IDEA AND
BOOSTED PRECIPITATION CHANCES TOWARDS 50 IN THE MITCHELL IOWA
COUNTY VICINITY.
DESPITE AN INFLUX OF SOME CLOUDS TODAY...THERE SHOULD BE ENOUGH SUN
AROUND TO COMBINE WITH 925MB TEMPS OF 7-10C AT 18Z TO BOOST HIGHS
INTO THE MID 50S TO LOW 60S. LOOKS BREEZY AS WELL WITH 925MB WINDS
BLOWING AT 20-25 KT. PASSAGE OF COLD FRONT WITH ALLOW COLDER LOW
LEVEL CANADIAN AIR TO INFILTRATE THE REGION. 925MB TEMPS FALL TO
0-4C BY 12Z SUNDAY. CLOUDS FROM THE F-GEN AND A BREEZE TURNING
NORTHERLY WILL HELP WITH MIXING AND TO KEEP TEMPERATURES UP
SOME...BUT ANTICIPATE LOWS IN THE 30S IN MOST LOCATIONS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 235 AM CDT SAT MAY 3 2014
STARTING OFF WITH SUNDAY...MUCH OF THE FORECAST AREA LIES IN THE
RIGHT ENTRANCE REGION WITH A LOW TO MID-LEVEL FRONTOGENESIS ZONE
ACROSS LOCATIONS SOUTHWEST OF I-94. SIMILAR TO LATE TONIGHT...THE
03.00Z GFS DEPICTS VERY LITTLE PRECIPITATION WITH THIS
FORCING...WHEREAS THE 03.00Z NAM/REGIONAL CANADIAN/ECMWF ALL HAVE A
BAND OF RAIN OVER SOUTHERN MINNESOTA...NORTHEAST IOWA AND FAR
SOUTHWEST WI. HAVE FOLLOWED THE MAJORITY AND KEPT PRECIPITATION
CHANCES HIGH...60-70 PERCENT...OVER THIS ZONE. THIS BAND OF RAIN
LOOKS TO BE MOSTLY A MORNING IMPACT AS THE RIGHT ENTRANCE REGION
SHIFTS QUICKLY OFF TO THE EAST AND THE FRONTOGENESIS ZONE WEAKENS.
AFTER 18Z SUNDAY...THE FORECAST AREA SHOULD BE DRY. TEMPERATURES ARE
LIKELY TO BE QUITE A BIT COOLER...ESPECIALLY WHERE IT RAINS...
COMPARED TO SATURDAY.
UPPER RIDGING THAT HAS BEEN STUCK OVER THE WESTERN U.S. IS THEN
PROGGED TO START PUSHING EAST TOWARDS THE REGION...FORCED BY A DEEP
TROUGH DEVELOPING ALONG THE WEST COAST BY TUESDAY MORNING. MODEL
CONSENSUS IS TO HAVE THE RIDGE AXIS OVER THE FORECAST AREA AT 00Z
WEDNESDAY. UNTIL THEN...THE AREA WILL LIE ON THE SUBSIDENT SIDE
FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THERE WERE INDICATIONS
OF POSSIBLE RAIN FROM A WEAK MID-LEVEL FRONTOGENESIS ZONE OVER THE
AREA ON MONDAY IN PAST MODEL RUNS. HOWEVER...THE 03.00Z GFS AND NAM
ARE NOW DRY. THE 03.00Z CANADIAN STILL DEPICTS A LITTLE LIGHT QPF.
HAVE DECIDED TO KEEP A 20 PERCENT CHANCE GOING...BUT IF MODEL TRENDS
CONTINUE...THESE CHANCES COULD BE REMOVED. DRY CONDITIONS SHOULD BE
THE RULE OTHERWISE FROM SUNDAY NIGHT THROUGH TUESDAY. BEING UNDER
THE INFLUENCE OF CANADIAN HIGH PRESSURE SITTING OVER UPPER
MICHIGAN...EXPECTING TEMPERATURES TO REMAIN BELOW NORMAL WITH
GRADUAL MODIFICATION EACH DAY. MONDAY NIGHT COULD GET RELATIVELY
SPEAKING CHILLY ACROSS CENTRAL WI WITH DRY AIR AND A LIGHT GRADIENT
IN PLACE.
FOR TUESDAY NIGHT AND BEYOND THROUGH THE END OF NEXT WEEK...THE
WEATHER GETS MORE ACTIVE. MUCH OF THIS IS IN RESPONSE TO THE WEST
COAST TROUGH MOVING EASTWARD...PUTTING THE AREA INTO A WARM AND
MOIST AIR ADVECTION REGIME. MODELS OVERALL ARE IN SURPRISINGLY GOOD
AGREEMENT ON THE WEST COAST TROUGH PROGRESSION...AS WELL AS THE
SURFACE LOW PRESSURE SYSTEM THAT ACCOMPANIES THE WEST COAST
TROUGH. GENERAL CONSENSUS IS FOR ELEVATED SHOWERS AND
THUNDERSTORMS TO DEVELOP OVER THE AREA TUESDAY NIGHT AS 850MB
MOISTURE TRANSPORT INCREASES AT US. 850MB COMPUTED CAPE FROM THE
03.00Z ECMWF FAIRLY IMPRESSIVE OVER IA AT 12Z WED...BETWEEN
1500-2000 J/KG. WILL NEED TO KEEP A CLOSE EYE ON LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING FOR POSSIBLE SEVERE WEATHER...WITH
LARGE HAIL THE MOST LIKELY CONCERN. ELEVATED CONVECTION PUSHES
EAST AND DIMINISHES ON WEDNESDAY... FOLLOWED BY POTENTIALLY MORE
ELEVATED CONVECTION WEDNESDAY NIGHT. POSITION OF THIS ROUND MORE
UNCERTAIN AS THE 03.00Z ECMWF IS MUCH FARTHER NORTH THAN THE
03.00Z GFS... SUGGESTING IN UPPER MI VERSUS ALONG I-90. SHOULD THE
FARTHER NORTH ECMWF OCCUR...BOTH WEDNESDAY NIGHT AND THURSDAY LOOK
QUITE WARM GIVEN HOW THE WEATHER HAS BEEN. ECMWF PUSHES LOW 80S
ACROSS MUCH OF WI FOR HIGHS ON THURSDAY. MEX GUIDANCE ACTUALLY NOT
TOO FAR OFF EITHER. COLD FRONT CROSSES SOMETIME EITHER THURSDAY OR
THURSDAY NIGHT AND THIS TIMING WILL BE CRITICAL TO SEE IF ANY
SURFACE BASED CONVECTION IMPACTS THE AREA. 03.00Z ECMWF SAYS THIS
CONVECTION FIRES EAST OF THE FORECAST AREA WHEREAS THE GFS IS MUCH
SLOWER AND MOST OF THE AREA SEES CONVECTION THURSDAY NIGHT.
NEEDLESS TO SAY 30-40 PERCENT CONSENSUS CHANCES SEEM WARRANTED.
BOTH SOLUTIONS ARE TRENDING TOWARDS COOLER AND DRIER WEATHER FOR
FRIDAY SO ONLY HAVE 20 PERCENT CHANCES THEN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1130 AM CDT SAT MAY 3 2014
UPPER LEVEL SHORTWAVE COUPLED WITH A SFC TROUGH WILL MOVE ACROSS
NORTHERN PORTIONS OF THE REGION THIS AFTERNOON/EVENING. WEAK MID
LEVEL INSTABILITY TO PLAY WITH...PER BUFKIT SOUNDINGS...WHICH
RESULTS IN SCATTERED -SHRA. DECENT AGREEMENT IN THE MESO MODELS WITH
KEEPING THE BULK OF THE SHOWERS ALONG AND NORTH OF I-94.
HOWEVER...WEAK LOW LEVEL FRONTOGENETIC LIFT STILL INDICATED SOUTH OF
THERE FOR LATE AFTERNOON/EARLY EVENING. COULD RESULT IN ISOLD
ACTIVITY...BUT NOT ENOUGH CONFIDENCE TO ADD TO THE FORECAST AT THIS
TIME.
CLOUDS ARE GOING TO BE VARIABLE TODAY THROUGH TONIGHT...WITH PERIODS
OF SCT TO BKN. CIG HEIGHTS WILL STAY VFR.
ANOTHER UPPER LEVEL SHORTWAVE IS SLATED TO SPIN SOUTHEAST FROM THE
PLAINS TO ACROSS IA ON SUNDAY. MODELS ALL FAVOR A RELATIVELY THIN
BAND OF -SHRA WITH THE FEATURE...TRENDING IT SOUTH OF THE TAF SITES.
CLOSE ENOUGH TO KRST TO WARRANT A VCSH FOR NOW THOUGH.
FOR WINDS...GOOD MIXING THIS AFTERNOON AND DRY SUB CLOUD LAYER WILL
RESULT IN WIND GUSTS. MOMENTUM TRANSFER VIA BUFKIT SOUNDINGS ISN/T
THAT MUCH OVER THE EXPECTED GRADIENT WINDS HOWEVER. THIS WILL SETTLE
DOWN WITH THE LOSS OF DAYTIME HEATING THIS EVENING.
&&
.HYDROLOGY...
ISSUED AT 235 AM CDT SAT MAY 3 2014
RUNOFF CONTINUES TO FILTER THROUGH THE TRIBUTARIES AND INTO THE
MISSISSIPPI RIVER. BLACK RIVER AT GALESVILLE CURRENTLY THE ONLY
TRIBUTARY SITE IN FLOOD...BUT THE STAGE IS FALLING AND SHOULD BE
BELOW FLOOD STAGE LATER THIS MORNING. ALONG THE MISSISSIPPI
RIVER...MOST LOCATIONS ARE STILL RISING. PRESENTLY WABASHA THE
ONLY SITE ABOVE FLOOD STAGE...BUT WINONA...LA CROSSE...MCGREGOR AND
GUTTENBERG DAM 10 WILL FOLLOW OVER THE NEXT FEW DAYS. STILL NO MAJOR
RAINFALL ANTICIPATED THROUGH TUESDAY...WHICH WILL HELP GET THE
TRIBUTARIES DOWN BEFORE POSSIBLY HEAVIER RAIN ASSOCIATED WITH STORMS
COMES IN TUESDAY NIGHT AND WEDNESDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK
HYDROLOGY....AJ