Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/17/14
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
435 PM PDT FRI MAY 16 2014
.SYNOPSIS...A COOLING TREND WILL CONTINUE THROUGH THE WEEKEND INTO
EARLY NEXT WEEK AS A STORM SYSTEM BRUSHES NORTHERN CA.
DRY CONDITIONS WILL PREVAIL THROUGH THE FORECAST AS ANY RAIN
CHANCES REMAIN TO THE NORTH AND EAST OF THE AREA.
&&
.DISCUSSION...AS OF 02:12 PM PDT FRIDAY...AN UPPER LOW CONTINUES
TO MOVE EAST TOWARD THE PAC NW COASTLINE THIS AFTERNOON...BRINGING
A COOLER AIRMASS TO THE REGION. 850 MB TEMPERATURES FELL BETWEEN 1
AND 2 DEGREES C THIS AFTERNOON COMPARED TO YESTERDAY AFTERNOON.
THIS IN COMBINATION WITH MUCH STRONGER ONSHORE FLOW RESULTED IN
SURFACE TEMPERATURES BETWEEN 6 AND 17 DEGREES COOLER COMPARED TO
YESTERDAY. TEMPERATURES WERE GENERALLY IN THE 60S ALONG THE
COAST...TO THE 70S TO MID 80S INLAND.
DIFFICULT STRATUS FORECAST FOR THE OVERNIGHT HOURS...AS THE WRF
AND HRRR INDICATE PATCHY LOW CLOUDS ALONG THE COASTLINE...BY NO
MEANS A SOLID STRATUS FIELD. LOW CLOUDS MAY IMPACT THE COASTLINE
AS WELL AS A FEW AREAS INLAND EARLY TOMORROW MORNING. IF ANY LOW
CLOUDS DO DEVELOP...EXPECT AN EARLY DISSIPATION ON SATURDAY
MORNING. FORECASTER CONFIDENCE LOW ON LOW CLOUD TIMING AND
FORMATION. OTHERWISE...TEMPERATURES BY EARLY SATURDAY MORNING WILL
RANGE FROM THE UPPER 40S TO MID 50S...SIMILAR TO TEMPERATURE
READINGS FROM THIS MORNING AND NEAR NORMAL FOR THE MIDDLE OF MAY.
THE COOLING TREND WILL CONTINUE INTO THE WEEKEND AND THE BEGINNING
OF NEXT WEEK AS THE UPPER LOW MOVES SOUTHEAST INTO OREGON.
TEMPERATURES OVER THE WEEKEND WILL RANGE FROM THE UPPER 50S TO 60S
ALONG THE COAST...TO THE 70S TO LOW 80S INLAND. MONDAY LOOKS LIKE
THE COOLEST DAY OF THE FORECAST WITH THE UPPER LOW MOVING INTO
NORTHERN CA...TEMPERATURES WILL DROP INTO THE LOW TO MID 70S
INLAND.
THE FORECAST MODELS ARE IN GOOD AGREEMENT WITH THE TIMING AND
LOCATION OF THE UPPER LOW...WITH RAIN CHANCES REMAINING TO THE
NORTH AND EAST OF THE AREA. THERE IS AN OFF CHANCE THAT WE COULD
SEE A FEW SPRINKLES IN THE NORTH BAY ON MONDAY AFTERNOON...HOWEVER
FORECASTER CONFIDENCE IS SO LOW THAT IT WAS NOT ADDED TO THE
FORECAST.
850 MB TEMPERATURES BEGIN TO SLOWLY RECOVER TUESDAY INTO THE END
OF NEXT WEEK...WITH A WARMING TREND IN STORE FOR THE SECOND HALF
OF THE WEEK. BY FRIDAY...TEMPERATURES SHOULD BE BACK TO SLIGHTLY
ABOVE NORMAL VALUES...WITH MOST INLAND LOCATIONS WARMING INTO THE
UPPER 70S TO MID 80S.
&&
.AVIATION...AS OF 4:35 PM PDT FRIDAY...CLEAR SKIES ARE BEING
REPORTED ACROSS THE FORECAST AREA THIS AFTERNOON. 24 HOUR CHANGES
IN TEMPERATURE AND HUMIDITY SHOW 8F TO 12F DEGREES OF COOLING AT
THE TERMINALS AND THE DEW POINT RISING AROUND 4F DEGREES. THE
ONSHORE SURFACE PRESSURE GRADIENT HAS ALSO INCREASED OVER THE PAST
24 HOURS. THE COMBINATION OF THESE FACTORS SUGGEST THAT A MARINE
AIRMASS HAS BEGUN TO REPLACE THE HOT DRY MASS THAT HAS BEEN
IN PLACE ALL WEEK. THEREFORE WE CAN EXPECTED STRATUS TO RETURN TO
THE TERMINALS OVERNIGHT.
VICINITY OF KSFO...GUSTY WEST WINDS 20KT GUSTING TO 25KT WILL
PERSIST THROUGH MIDNIGHT. WEST WINDS WILL 15KT WITH GUSTS TO 20 KT
ARE EXPECTED TO PERSIST OVERNIGHT. STRATUS BKN- OVC012 WILL ARRIVE
BY 1000Z.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...WEST WINDS 10 TO 15 KT WITH PERSIST
THROUGH EARLY EVENING. STRATUS BKN-OVC010-015 WILL ARRIVE SHORTLY
AFTER MIDNIGHT.
&&
.MARINE...AS OF 02:12 PM PDT FRIDAY...GUSTY NORTHWEST WINDS WILL
PERSIST THROUGH THE WEEKEND AS HIGH PRESSURE BUILDS OVER THE
EASTERN PACIFIC. THE MODERATE WINDS WILL RESULT IN STEEP FRESH
SWELL.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 3 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 3 AM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PT ARENA TO PT REYES 10-60 NM
SCA...PT REYES TO PIGEON PT 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 10-60 NM
SCA...SF BAY SOUTH OF THE BAY BRIDGE UNTIL 10 PM
SCA...MONTEREY BAY UNTIL 10 PM
SCA...PIGEON PT TO PT PINOS 10-60 NM UNTIL 10 PM
&&
$$
PUBLIC FORECAST: RILEY
AVIATION: LARRY
MARINE: SIMS
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AREA FORECAST DISCUSSION
NWS NEW YORK NY
804 PM EDT FRI MAY 16 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL PUSH THROUGH THE REGION TONIGHT.
HIGH PRESSURE BUILDS IN GRADUALLY FROM THE WEST IN THE WAKE OF THE
FRONT INTO NEXT WEEK AS LOW PRESSURE MEANDERS OVER THE WESTERN
ATLANTIC THROUGH TUESDAY NIGHT. HIGH PRESSURE BUILDS OVER THE AREA
ON WEDNESDAY...AND THEN SLIDES TO THE EAST ON THURSDAY AS A WARM
FRONT APPROACHES FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
COLD FRONT IS RIGHT ON OUR WESTERN DOORSTEP AND WILL MAKE ITS WAY
THROUGH ORANGE COUNTY OVER THE NEXT HOUR OR SO.
LOWERED PRECIP AMOUNTS AS MODELS ARE BACKING OFF A BIT ON THE
STORM TOTALS. WILL KEEP THE FLASH FLOOD WATCH UP AS THERE IS AN
AREA OF MODERATE TO LOCALLY HEAVY RAINFALL JUST OFFSHORE OF LONG
ISLAND MAKING ITS WAY ONSHORE CURRENTLY.
ALSO...TOOK OUT MENTION OF THUNDER AS THERE HAS BEEN NO THUNDER
OBSERVED WITH ANY OF THE SHOWERS THUS FAR AS WELL AS ANY OF THE
SHOWERS UPSTREAM.
OTHERWISE...MINOR CHANGES MADE TO REFLECT CURRENT OBS.
WET NIGHT IN STORE FOR THE TRI STATE AREA AS A COLD FRONT SLOWLY
APPROACHES FROM THE WEST...WITH PERSISTENT TRAIN OF PCPN PUSHING
NORTH OUT AHEAD OF THE FRONT. ALOFT...DEEP TROUGH EXTENDING WELL
INTO THE SE US SLOWLY MOVES EAST...WITH A SLIGHT NEGATIVE TILT
ASSOCIATED WITH IT AS SEEN VIA THE LATEST WATER VAPOR IMAGERY. 19Z
RADAR IMAGERY INDICATING BATCH OF HEAVIER PCPN TREKKING ALONG THE
NEW JERSEY COAST...WITH THE EXPECTATION OF PUSHING INTO THE NYC
METRO AREA BETWEEN 20-22Z. HRRR BEEN CAPTURING THE PCPN
TODAY...AND BACKS UP THE TRACK OF THIS PCPN...AND LOOK TO MAINTAIN
PCPN IN THE AREA THEN THROUGH 00Z...SO WILL GO CATEGORICAL POPS
FOR THIS TIME PERIOD...WITH THE POTENTIAL OF EMBEDDED HEAVIER RAIN
SHOWERS. THUNDER HAS BEEN MINIMAL DURING THE DAY WITH THE
PCPN...BUT WITH SOME WEAK INSTABILITY STILL IN PLACE AND DECENT
SHEAR...WILL CONTINUE TO MENTION ISO TSTM THROUGH THIS EVENING.
FOR FLOODING CONCERNS...PLEASE REFER TO HYDROLOGY SECTION.
QUESTION THEN BECOMES HOW LONG THE HEAVIER PCPN PERSISTS INTO THIS
EVENING. MESO MODELS SUGGEST AN ACTUAL BREAK POSSIBLY AROUND 00Z
AS THE FIRST BULK OF HEAVIER PCPN PUSHES NORTH...AND A SECOND AREA
BEGINS TO DEVELOP AS THE COLD FRONT SLOWLY MOVES INTO EASTERN NJ
AND NY. AT THE SURFACE...THIS IS BACKED WITH THE DEVELOPMENT OF A
WEAK WAVE OF LOW PRESSURE ALONG THE FRONT AS WELL AS A
STRENGTHENING LLJ PUSHING TO THE EAST. THINKING IS WE SEE ANOTHER
ROUND OF HEAVIER PCPN...THOUGH WITH THE AXIS A BIT FURTHER TO THE
EAST...MORE ALIGNING OVER WESTERN CT AND LONG ISLAND...GENERALLY
OCCURRING AFTER 01Z. THE LINE OF HEAVIER PCPN PROGRESSES EAST THEN
AS THE FRONT PUSHES EAST...HITTING EASTERN LONG ISLAND AND CT AFTER
06Z. DESPITE CONTINUAL STRONGER SHEAR..INSTABILITY VALUES REALLY
BEGIN TO TAPER OFF...SO THINKING ISO TSTM THREAT DIMINISHES BY
06Z. AREAS OF THE NYC METRO DRY OUT BY 07Z...WITH AREAS OF EASTERN
CT/LI SEEING PCPN THROUGH 12Z.
STRONG SOUTHEASTERLY TO SOUTHERLY FLOW WILL CONTINUE INTO THIS
EVENING...WITH GUSTS UP TO 30-35 MPH PSBL THROUGH 00Z...AND GUSTS
BETWEEN 25 AND 30 MPH THROUGH 06Z. AS THE FRONT PUSHES
THROUGH...WINDS DRASTICALLY DROP OFF WHILE SHIFTING TO THE WEST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE STRETCHED ACROSS FAR EASTERN CT/LI BY 12Z
SATURDAY...THEN PUSHING OFF TO THE EAST DURING THE DAY. SURFACE
HIGH BEGINS TO BUILD WELL TO THE WEST...AND WILL BE SLOW TO PUSH
INTO THE NORTHEAST. LINGERING LIGHT RAIN SHOWERS PSBL EARLY SAT
MORNING OVER EASTERN AREAS...WITH CONDITIONS DRYING OUT ACROSS THE
AREA FOR THE DAY. WEAK TROUGHING SPLITTING CENTRAL NY COMBINED
WITH STRONG SHORTWAVE PASSING ALONG THE UPPER LEVEL TROUGH COULD
TRIGGER A LIGHT RAIN SHOWER SAT AFTERNOON...BUT WITH DRIER AIR
MOVING IN BEHIND THE FRONT...NOT CONFIDENT IN ANYTHING DEVELOPING
AS FAR SOUTH AS SOUTHEASTERN NY AND THUS WILL CARRY DRY WEATHER
SAT THROUGH SAT NIGHT.
THE COOLER AIR IS SLOW TO SEEP INTO THE AREA...AND WITH CLEARING
SKIES...AND DOWNSLOPING WINDS BY SAT AFTERNOON...SHOULD SEE TEMPS
PUSH TO NEAR NORMAL. NEAR NORMAL TEMPS PERSIST SAT NIGHT WITH
INCREASING CLOUD COVER WITH THE PASSAGE OF MULTIPLE WEAK SHORTWAVES
ROUNDING THE BASE OF THE UPPER LEVEL TROUGH.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
THE LONG TERM WILL BE DOMINATED BY AN OMEGA BLOCK FOR MUCH OF THE
PERIOD...WITH UPPER LEVEL TROUGHINESS FOR THE WEST AND EAST COASTS
AND UPPER LEVEL RIDGING IN BETWEEN...WHICH MEANS THINGS WILL MOVE
SLOWLY...WITH UNSETTLED AND COOL CONDITIONS.
LOW PRESSURE WILL REMAIN OFF THE EAST COAST THROUGH TUESDAY
NIGHT...AND BECOME STACKED BY AN UPPER LEVEL LOW MONDAY NIGHT. UPPER
LEVEL TROUGH IN ASSOCIATION WITH THIS LOW WILL SLOWLY MOVE THROUGH
THE REGION. WITH THIS TROUGH WILL BE A COLD POOL ALOFT THAT WILL
HELP TO DESTABILIZE THE ATMOSPHERE AS A SURFACE SHORT WAVE MOVES
THROUGH SUNDAY AFTERNOON. WEAK FORCING ASSOCIATED WITH THIS
TROUGH...SO ONLY SLIGHT CHANCE EXPECTED DURING THE AFTERNOON HOURS
ON SUNDAY MAINLY ACROSS CT.
ANOTHER SURFACE SHORT WAVE MOVES THROUGH MONDAY EVENING INTO MONDAY
NIGHT. SO AGAIN...SLIGHT CHANCE FOR SHOWERS THROUGH TUESDAY MORNING.
LOW PRESSURE OFF THE EAST COAST LOOKS TO RETROGRADE A BIT MONDAY
NIGHT INTO TUESDAY...PRODUCING SOME SHOWERS FOR CT AND EASTERN LONG
ISLAND TUE AFTERNOON.
JUST AS THE LOW OFF THE EAST COAST STARTS TO EXIT THE AREA ON
WEDNESDAY...A WARM FRONT WILL APPROACH WITH AN ASSOCIATED SURFACE LOW
POSITIONED OVER THE EASTERN GREAT LAKES BY THURSDAY MORNING. CHANCES
FOR PRECIP WILL INCREASE FROM WEDNESDAY THROUGH THURSDAY AFTERNOON.
THIS LOW IS FORECAST TO THEN TRACK SOUTHEAST...PASSING WELL SOUTH
AND EAST OF THE AREA BY FRIDAY MORNING. DO NOTE SOME MINOR SURFACE
BASED CAPE DURING THE DAY WEDNESDAY AND THURSDAY...SO AN ISOLATED
THUNDERSTORM IS POSSIBLE.
WITH THE PERSISTENT TROUGHINESS...TEMPERATURES WILL AVERAGE NEAR
NORMAL TO SLIGHTLY BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
A COLD FRONT MOVES THROUGH AROUND MIDNIGHT.
GENERALLY SE WINDS 15-20KT G25-30KT THRU MIDNIGHT BEFORE WINDS
DIMINISH AND SHIFT SW.
MOSTLY IFR IN RAIN BEFORE AROUND MIDNIGHT. IMPROVEMENT TO VFR WITHIN
A COUPLE OF HOURS AFTER THE RAIN STOPS/WIND SHIFT TO SW.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: SUSTAINED WINDS MIGHT PREVAIL BELOW 10 KT
THROUGH MIDNIGHT. SOUTH WINDS AROUND 45KT AT 2000FT UNTIL AROUND
01-02Z.
KJFK FCSTER COMMENTS: SOUTH WINDS AROUND 45KT AT 2000FT UNTIL
AROUND 02Z. OCCASIONAL GUSTS AROUND 35KT POSSIBLE UNTIL 01-02Z.
KLGA FCSTER COMMENTS: SOUTH WINDS AROUND 45KT AT 2000FT UNTIL
AROUND 02Z. OCCASIONAL GUSTS AROUND 35KT POSSIBLE UNTIL 01-02Z.
KTEB FCSTER COMMENTS: SOUTH WINDS AROUND 45KT AT 2000FT UNTIL
AROUND 01-02Z.
KHPN FCSTER COMMENTS: SOUTH WINDS AROUND 45KT AT 2000FT UNTIL
AROUND 02Z.
KISP FCSTER COMMENTS: SOUTH WINDS AROUND 45KT AT 2000FT FROM
APPROX 02Z-05Z.
.OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...
.SATURDAY NIGHT...VFR.
.SUNDAY-SUNDAY NIGHT...VFR.
.MONDAY-WEDNESDAY...MAINLY VFR.
&&
.MARINE...
WEB CAMS AT THE SHORES AROUND LONG ISLAND INDICATE THAT DENSE FOG
HAS REFORMED ON THE WATERS. WITH THE COLD FRONT MOVING SLOWLY
ACROSS THE WATERS TONIGHT...IT WILL TAKE A WHILE FOR DRIER AIR TO
WORK IN BEHIND IT. THEREFORE...HAVE ISSUED A DENSE FOG ADVSY FOR
ALL WATERS THROUGH TONIGHT. WESTERN MARINE ZONES MAY IMPROVE
BEFORE 10Z AND ADVSY COULD BE CANCELLED EARLY.
OTHERWISE...A STRONG SOUTHEASTERLY TO SOUTHERLY FLOW AHEAD OF THE
APPROACHING COLD FRONT WILL KEEP THE POTENTIAL FOR GUSTS 25 TO 30
KTS THROUGH THIS EVENING...WITH SEAS BUILDING ON THE OCEAN TO 6 TO
8 FT. THUS WILL MAINTAIN THE SCA IN EFFECT FOR ALL WATERS THROUGH
EARLY SAT MORNING. AS THE COLD FRONT PUSHES EAST...WINDS TAPER
OFF...SO STILL EXPECTING WESTERN WATERS TO DROP BELOW SCA EARLY
SAT MORNING...WITH EASTERN WATERS BY LATER SAT MORNING. SEAS WILL
LINGER ABOVE 5 FT ON THE OCEAN THROUGH SATURDAY SO WILL KEEP THE
SCA GOING ON THE OCEAN DURING THE DAY. ALL WATERS EXPECTED TO DROP
BELOW SCA CRITERIA FOR SAT NIGHT.
WINDS AND WAVES THEN REMAIN BELOW SCA CRITERIA THROUGH THE COMING WEEK.
&&
.HYDROLOGY...
WIDESPREAD MODERATE TO LOCALLY HEAVY RAIN MOVING OVER NJ AND LOWER
HUDSON RIVER VALLEY COUNTIES...AND WILL SPREAD EAST INTO THIS
EVENING. RAIN EXPECTED TO END BY SATURDAY MORNING. CURRENTLY
EXPECTING 1 TO 2 INCHES BASIN AVG QPF...WITH LOCALLY HIGHER
AMOUNTS POSSIBLE IN HEAVIER CONVECTION. FLASH FLOOD WATCH
CONTINUES FOR ENTIRE TRI STATE AREA MINUS SUFFOLK COUNTY.
NO SIGNIFICANT RAINFALL IS EXPECTED IN THE LONG TERM.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE RUNNING RELATIVELY HIGH WITH THE FULL MOON
THAT OCCURRED ON WEDNESDAY.
HAVE ISSUED A COASTAL FLOOD STATEMENT FOR SOUTHWESTERN SHORES OF
LONG ISLAND AND THR SHORES OF WESTERN LONG ISLAND SOUND FOR THE TIMES
OF HIGH TIDE TONIGHT. TIDES ARE EXPECTED TO BE ABOUT 1 FT HIGHER
THAN THE ASTRONOMICAL TIDE AT THE TIME OF HIGH TIDE. THUS...THE
HIGHER TIDES COMBINED WITH POTENTIALLY HEAVY RAINFALL COULD LEAD TO
LOCALIZED MINOR COASTAL FLOODING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR CTZ009.
FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR CTZ005>008-
010>012.
NY...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR NYZ067-069>075-
176>179.
FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR NYZ068.
NJ...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR NJZ002-004-006-
103>108.
MARINE...DENSE FOG ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ330-335-338-
340-345-350-353-355.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ335-338-
345.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ330-340.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ353-355.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR ANZ350.
&&
$$
SYNOPSIS...JP/SEARS
NEAR TERM...JP/SEARS
SHORT TERM...SEARS
LONG TERM...JP
AVIATION...JC
MARINE...JP/SEARS
HYDROLOGY...JP/SEARS
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
748 PM EDT FRI MAY 16 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL PUSH THROUGH THE REGION TONIGHT.
HIGH PRESSURE BUILDS IN GRADUALLY FROM THE WEST IN THE WAKE OF THE
FRONT INTO NEXT WEEK AS LOW PRESSURE MEANDERS OVER THE WESTERN
ATLANTIC THROUGH TUESDAY NIGHT. HIGH PRESSURE BUILDS OVER THE AREA
ON WEDNESDAY...AND THEN SLIDES TO THE EAST ON THURSDAY AS A WARM
FRONT APPROACHES FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
COLD FRONT IS RIGHT ON OUR WESTERN DOORSTEP AND WILL MAKE ITS WAY
THROUGH ORANGE COUNTY OVER THE NEXT HOUR OR SO.
LOWERED PRECIP AMOUNTS AS MODELS ARE BACKING OFF A BIT ON THE
STORM TOTALS. WILL KEEP THE FLASH FLOOD WATCH UP AS THERE IS AN
AREA OF MODERATE TO LOCALLY HEAVY RAINFALL JUST OFFSHORE OF LONG
ISLAND MAKING ITS WAY ONSHORE CURRENTLY.
ALSO...TOOK OUT MENTION OF THUNDER AS THERE HAS BEEN NO THUNDER
OBSERVED WITH ANY OF THE SHOWERS THUS FAR AS WELL AS ANY OF THE
SHOWERS UPSTREAM.
OTHERWISE...MINOR CHANGES MADE TO REFLECT CURRENT OBS.
WET NIGHT IN STORE FOR THE TRI STATE AREA AS A COLD FRONT SLOWLY
APPROACHES FROM THE WEST...WITH PERSISTENT TRAIN OF PCPN PUSHING
NORTH OUT AHEAD OF THE FRONT. ALOFT...DEEP TROUGH EXTENDING WELL
INTO THE SE US SLOWLY MOVES EAST...WITH A SLIGHT NEGATIVE TILT
ASSOCIATED WITH IT AS SEEN VIA THE LATEST WATER VAPOR IMAGERY. 19Z
RADAR IMAGERY INDICATING BATCH OF HEAVIER PCPN TREKKING ALONG THE
NEW JERSEY COAST...WITH THE EXPECTATION OF PUSHING INTO THE NYC
METRO AREA BETWEEN 20-22Z. HRRR BEEN CAPTURING THE PCPN
TODAY...AND BACKS UP THE TRACK OF THIS PCPN...AND LOOK TO MAINTAIN
PCPN IN THE AREA THEN THROUGH 00Z...SO WILL GO CATEGORICAL POPS
FOR THIS TIME PERIOD...WITH THE POTENTIAL OF EMBEDDED HEAVIER RAIN
SHOWERS. THUNDER HAS BEEN MINIMAL DURING THE DAY WITH THE
PCPN...BUT WITH SOME WEAK INSTABILITY STILL IN PLACE AND DECENT
SHEAR...WILL CONTINUE TO MENTION ISO TSTM THROUGH THIS EVENING.
FOR FLOODING CONCERNS...PLEASE REFER TO HYDROLOGY SECTION.
QUESTION THEN BECOMES HOW LONG THE HEAVIER PCPN PERSISTS INTO THIS
EVENING. MESO MODELS SUGGEST AN ACTUAL BREAK POSSIBLY AROUND 00Z
AS THE FIRST BULK OF HEAVIER PCPN PUSHES NORTH...AND A SECOND AREA
BEGINS TO DEVELOP AS THE COLD FRONT SLOWLY MOVES INTO EASTERN NJ
AND NY. AT THE SURFACE...THIS IS BACKED WITH THE DEVELOPMENT OF A
WEAK WAVE OF LOW PRESSURE ALONG THE FRONT AS WELL AS A
STRENGTHENING LLJ PUSHING TO THE EAST. THINKING IS WE SEE ANOTHER
ROUND OF HEAVIER PCPN...THOUGH WITH THE AXIS A BIT FURTHER TO THE
EAST...MORE ALIGNING OVER WESTERN CT AND LONG ISLAND...GENERALLY
OCCURRING AFTER 01Z. THE LINE OF HEAVIER PCPN PROGRESSES EAST THEN
AS THE FRONT PUSHES EAST...HITTING EASTERN LONG ISLAND AND CT AFTER
06Z. DESPITE CONTINUAL STRONGER SHEAR..INSTABILITY VALUES REALLY
BEGIN TO TAPER OFF...SO THINKING ISO TSTM THREAT DIMINISHES BY
06Z. AREAS OF THE NYC METRO DRY OUT BY 07Z...WITH AREAS OF EASTERN
CT/LI SEEING PCPN THROUGH 12Z.
STRONG SOUTHEASTERLY TO SOUTHERLY FLOW WILL CONTINUE INTO THIS
EVENING...WITH GUSTS UP TO 30-35 MPH PSBL THROUGH 00Z...AND GUSTS
BETWEEN 25 AND 30 MPH THROUGH 06Z. AS THE FRONT PUSHES
THROUGH...WINDS DRASTICALLY DROP OFF WHILE SHIFTING TO THE WEST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE STRETCHED ACROSS FAR EASTERN CT/LI BY 12Z
SATURDAY...THEN PUSHING OFF TO THE EAST DURING THE DAY. SURFACE
HIGH BEGINS TO BUILD WELL TO THE WEST...AND WILL BE SLOW TO PUSH
INTO THE NORTHEAST. LINGERING LIGHT RAIN SHOWERS PSBL EARLY SAT
MORNING OVER EASTERN AREAS...WITH CONDITIONS DRYING OUT ACROSS THE
AREA FOR THE DAY. WEAK TROUGHING SPLITTING CENTRAL NY COMBINED
WITH STRONG SHORTWAVE PASSING ALONG THE UPPER LEVEL TROUGH COULD
TRIGGER A LIGHT RAIN SHOWER SAT AFTERNOON...BUT WITH DRIER AIR
MOVING IN BEHIND THE FRONT...NOT CONFIDENT IN ANYTHING DEVELOPING
AS FAR SOUTH AS SOUTHEASTERN NY AND THUS WILL CARRY DRY WEATHER
SAT THROUGH SAT NIGHT.
THE COOLER AIR IS SLOW TO SEEP INTO THE AREA...AND WITH CLEARING
SKIES...AND DOWNSLOPING WINDS BY SAT AFTERNOON...SHOULD SEE TEMPS
PUSH TO NEAR NORMAL. NEAR NORMAL TEMPS PERSIST SAT NIGHT WITH
INCREASING CLOUD COVER WITH THE PASSAGE OF MULTIPLE WEAK SHORTWAVES
ROUNDING THE BASE OF THE UPPER LEVEL TROUGH.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
THE LONG TERM WILL BE DOMINATED BY AN OMEGA BLOCK FOR MUCH OF THE
PERIOD...WITH UPPER LEVEL TROUGHINESS FOR THE WEST AND EAST COASTS
AND UPPER LEVEL RIDGING IN BETWEEN...WHICH MEANS THINGS WILL MOVE
SLOWLY...WITH UNSETTLED AND COOL CONDITIONS.
LOW PRESSURE WILL REMAIN OFF THE EAST COAST THROUGH TUESDAY
NIGHT...AND BECOME STACKED BY AN UPPER LEVEL LOW MONDAY NIGHT. UPPER
LEVEL TROUGH IN ASSOCIATION WITH THIS LOW WILL SLOWLY MOVE THROUGH
THE REGION. WITH THIS TROUGH WILL BE A COLD POOL ALOFT THAT WILL
HELP TO DESTABILIZE THE ATMOSPHERE AS A SURFACE SHORT WAVE MOVES
THROUGH SUNDAY AFTERNOON. WEAK FORCING ASSOCIATED WITH THIS
TROUGH...SO ONLY SLIGHT CHANCE EXPECTED DURING THE AFTERNOON HOURS
ON SUNDAY MAINLY ACROSS CT.
ANOTHER SURFACE SHORT WAVE MOVES THROUGH MONDAY EVENING INTO MONDAY
NIGHT. SO AGAIN...SLIGHT CHANCE FOR SHOWERS THROUGH TUESDAY MORNING.
LOW PRESSURE OFF THE EAST COAST LOOKS TO RETROGRADE A BIT MONDAY
NIGHT INTO TUESDAY...PRODUCING SOME SHOWERS FOR CT AND EASTERN LONG
ISLAND TUE AFTERNOON.
JUST AS THE LOW OFF THE EAST COAST STARTS TO EXIT THE AREA ON
WEDNESDAY...A WARM FRONT WILL APPROACH WITH AN ASSOCIATED SURFACE LOW
POSITIONED OVER THE EASTERN GREAT LAKES BY THURSDAY MORNING. CHANCES
FOR PRECIP WILL INCREASE FROM WEDNESDAY THROUGH THURSDAY AFTERNOON.
THIS LOW IS FORECAST TO THEN TRACK SOUTHEAST...PASSING WELL SOUTH
AND EAST OF THE AREA BY FRIDAY MORNING. DO NOTE SOME MINOR SURFACE
BASED CAPE DURING THE DAY WEDNESDAY AND THURSDAY...SO AN ISOLATED
THUNDERSTORM IS POSSIBLE.
WITH THE PERSISTENT TROUGHINESS...TEMPERATURES WILL AVERAGE NEAR
NORMAL TO SLIGHTLY BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
A COLD FRONT WILL MOVE THROUGH LATE TONIGHT WITH HIGH PRESSURE
BUILDING WEST OF THE AREA THEREAFTER. IFR THROUGH MUCH OF TONIGHT
WITH LOCALIZED LIFR IN A MODERATE TO OCCASIONALLY HEAVY RAIN AND
SOME FOG. SOME LOCALIZED MVFR WILL BE SEEN BUT EXPECTING A
DETERIORATION OF CONDITIONS TO LOWER CATEGORIES BY LATE AFTERNOON.
WINDS OUT OF THE SE AROUND 20 KT GUSTING TO AROUND 30 KT. LOCALLY AT
TIMES...GUSTS COULD BE A FEW KTS HIGHER THAN FORECAST ESPECIALLY IN
ANY HEAVIER RAIN. LLWS CONTINUES WITH S WINDS AROUND 50 KT AT 2KFT.
ANY THUNDERSTORMS WILL BE SPARSE IN COVERAGE LATE THIS AFTERNOON
THROUGH THE EVENING. TOO MUCH UNCERTAINTY IN TIMING/LOCATION TO
PINPOINT THUNDERSTORMS SO LEFT OUT OF TAFS FOR TIME BEING.
A GRADUAL IMPROVEMENT TO CIGS/VSBY EXPECTED OVERNIGHT INTO SATURDAY
MORNING FROM WEST TO EAST WITH A MORE WESTERLY FLOW DEVELOPING
AROUND 10 KT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: CIGS COULD POSSIBLY DROP TO LIFR THROUGH THE
EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR OR TWO. WIND
DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST LATER TONIGHT
WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE TO SW-W FLOW.
KJFK FCSTER COMMENTS: CIGS MAY BRIEFLY FLUCTUATE BETWEEN LIFR AND IFR
THROUGH THE EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR OR
TWO. WIND DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST LATER
TONIGHT WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE TO
SW-W FLOW.
KLGA FCSTER COMMENTS: CIGS MAY BRIEFLY FLUCTUATE BETWEEN IFR AND MVFR
THROUGH THE EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR OR
TWO. WIND DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST LATER
TONIGHT WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE TO
SW-W FLOW.
KTEB FCSTER COMMENTS: CIGS MAY BRIEFLY FLUCTUATE BETWEEN IFR AND MVFR
THROUGH THE EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR OR
TWO. WIND DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST LATER
TONIGHT WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE TO
SW-W FLOW.
KHPN FCSTER COMMENTS: CIGS MAY BRIEFLY FLUCTUATE BETWEEN IFR AND
MVFR THROUGH THE EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR
OR TWO. WIND DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST
LATER TONIGHT WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE
TO SW-W FLOW.
KISP FCSTER COMMENTS: CIGS MAY BRIEFLY FLUCTUATE BETWEEN LIFR AND IFR
THROUGH THE EARLY EVENING. TIMING OF +RA MAY BE OFF BY AN HOUR OR
TWO. WIND DIRECTION COULD DIFFER SIGNIFICANTLY FROM FORECAST LATER
TONIGHT WITH UNCERTAINTY ON TIMING OF WINDS SWITCHING FROM SE TO
SW-W FLOW.
.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
.SATURDAY AFTERNOON-SATURDAY NIGHT...VFR. W-SW GUSTS AROUND 15 KT.
.SUNDAY-SUNDAY NIGHT...VFR.
.MONDAY-WEDNESDAY...MAINLY VFR.
&&
.MARINE...
WEB CAMS AT THE SHORES AROUND LONG ISLAND INDICATE THAT DENSE FOG
HAS REFORMED ON THE WATERS. WITH THE COLD FRONT MOVING SLOWLY
ACROSS THE WATERS TONIGHT...IT WILL TAKE A WHILE FOR DRIER AIR TO
WORK IN BEHIND IT. THEREFORE...HAVE ISSUED A DENSE FOG ADVSY FOR
ALL WATERS THROUGH TONIGHT. WESTERN MARINE ZONES MAY IMPROVE
BEFORE 10Z AND ADVSY COULD BE CANCELLED EARLY.
OTHERWISE...A STRONG SOUTHEASTERLY TO SOUTHERLY FLOW AHEAD OF THE
APPROACHING COLD FRONT WILL KEEP THE POTENTIAL FOR GUSTS 25 TO 30
KTS THROUGH THIS EVENING...WITH SEAS BUILDING ON THE OCEAN TO 6 TO
8 FT. THUS WILL MAINTAIN THE SCA IN EFFECT FOR ALL WATERS THROUGH
EARLY SAT MORNING. AS THE COLD FRONT PUSHES EAST...WINDS TAPER
OFF...SO STILL EXPECTING WESTERN WATERS TO DROP BELOW SCA EARLY
SAT MORNING...WITH EASTERN WATERS BY LATER SAT MORNING. SEAS WILL
LINGER ABOVE 5 FT ON THE OCEAN THROUGH SATURDAY SO WILL KEEP THE
SCA GOING ON THE OCEAN DURING THE DAY. ALL WATERS EXPECTED TO DROP
BELOW SCA CRITERIA FOR SAT NIGHT.
WINDS AND WAVES THEN REMAIN BELOW SCA CRITERIA THROUGH THE COMING WEEK.
&&
.HYDROLOGY...
WIDESPREAD MODERATE TO LOCALLY HEAVY RAIN MOVING OVER NJ AND LOWER
HUDSON RIVER VALLEY COUNTIES...AND WILL SPREAD EAST INTO THIS
EVENING. RAIN EXPECTED TO END BY SATURDAY MORNING. CURRENTLY
EXPECTING 1 TO 2 INCHES BASIN AVG QPF...WITH LOCALLY HIGHER
AMOUNTS POSSIBLE IN HEAVIER CONVECTION. FLASH FLOOD WATCH
CONTINUES FOR ENTIRE TRI STATE AREA MINUS SUFFOLK COUNTY.
NO SIGNIFICANT RAINFALL IS EXPECTED IN THE LONG TERM.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES ARE RUNNING RELATIVELY HIGH WITH THE FULL MOON
THAT OCCURRED ON WEDNESDAY.
HAVE ISSUED A COASTAL FLOOD STATEMENT FOR SOUTHWESTERN SHORES OF
LONG ISLAND AND THR SHORES OF WESTERN LONG ISLAND SOUND FOR THE TIMES
OF HIGH TIDE TONIGHT. TIDES ARE EXPECTED TO BE ABOUT 1 FT HIGHER
THAN THE ASTRONOMICAL TIDE AT THE TIME OF HIGH TIDE. THUS...THE
HIGHER TIDES COMBINED WITH POTENTIALLY HEAVY RAINFALL COULD LEAD TO
LOCALIZED MINOR COASTAL FLOODING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR CTZ009.
FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR CTZ005>008-
010>012.
NY...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR NYZ067-069>075-
176>179.
FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR NYZ068.
NJ...FLASH FLOOD WATCH UNTIL 6 AM EDT SATURDAY FOR NJZ002-004-006-
103>108.
MARINE...DENSE FOG ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ330-335-338-
340-345-350-353-355.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ335-338-
345.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ330-340.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ353-355.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR ANZ350.
&&
$$
SYNOPSIS...JP/SEARS
NEAR TERM...JP/SEARS
SHORT TERM...SEARS
LONG TERM...JP
AVIATION...JM
MARINE...JP/SEARS
HYDROLOGY...JP/SEARS
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
656 AM EDT THU MAY 15 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT ACROSS THE REGION EARLY TODAY...ALLOWING
FOR WARMER AND MORE HUMID CONDITIONS TO DEVELOP. WINDY AND WARM
FRIDAY AHEAD OF AN APPROACHING COLD FRONT ALONG WITH ISOLATED
SHOWERS. LOCALLY HEAVY DOWNPOURS AND SCATTERED THUNDERSTORMS WILL
MOVE ACROSS THE REGION FRIDAY NIGHT AND SATURDAY AHEAD OF A SLOW
MOVING COLD FRONT. SEASONABLY COOL UNSTABLE AIR WILL THEN MOVE
IN...GENERATING CLOUDS AND SCATTERED SHOWERS THROUGH MIDWEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7AM UPDATE...
SHOWERS DEVELOPED BETWEEN 4 AND 5 AM OVER NORTHERN NEW
JERSEY...THESE ARE MOVING NORTH UP THE HUDSON VALLEY. HRRR MODEL
SHOWS THESE SHOWERS TRENDING NORTHEAST INTO THE BERKS AND
LITCHFIELD HILLS THIS MORNING. WE HAVE ADJUSTED POPS TO BRING A
CHANCE OF SHOWERS INTO THE AREA WEST OF THE CT RIVER BY 10 AM.
ALSO MINOR CHANGES TO TEMPS/DEWPTS/SKY BASED ON OBSERVATIONS.
PREVIOUS DISCUSSION...
11-3.9 IR CHANNEL SHOWS A BROAD AREA OF STRATUS CONTINUES TO
BUILD INTO PORTIONS OF NRN NEW ENGLAND THIS MORNING...ALTHOUGH
THE BACK EDGE IS BEGINNING TO SHOW SIGNS OF LIFTING OUT AT ACK
WITH SLIGHT NE PUSH OF WARM FRONT. OTHERWISE...ONLY A FEW SPOTS OF
FOG/DZ ACROSS THE REGION THIS MORNING AS THE BULK OF THIS INITIAL
ROUND OF MOISTURE IS MAINLY TRAPPED IN THE H95-H8 LAYER AND NOT
IMMEDIATELY AT THE SFC.
THIS SFC WARM FRONT SHOULD FINALLY BEGIN TO MOVE N AS INITIAL COLD
FRONTAL WAVE WELL TO THE W WILL MOVE INTO CANADA ALONG WITH ITS
SHORTWAVE...ALLOWING WINDS ALOFT ACROSS NEW ENGLAND TO SHIFT TO
THE S. THIS COMBINED DIURNAL TEMP INCREASES AFTER SUNRISE SHOULD
BE ENOUGH TO FINALLY GET IT MOVING. THE FRONT IS LIKELY ONLY TO
FULLY MANIFEST ITSELF AS AN INCREASE IN LOW LVL DWPTS...ALLOWING
THEM TO SHIFT INTO THE LOW 60S FOR MUCH OF THE DAY.
IN SPITE OF THIS WARM FRONTAL PASSAGE...UPPER LVL RIDGE AND SFC
HIGH PRES RIDGE TO THE E REMAIN IN CONTROL SOMEWHAT...TRAPPING THE
MOIST LAYER /AND STRATUS/ BENEATH SUBSIDENCE INVERSION.
THEREFORE...DO NOT EXPECT TEMP INCREASES TO BE AS HIGH AS THEY
COULD WITH H85 TEMPS IN AVERAGING AROUND 12C BY 18Z.
THEREFORE...WILL CAP MOST TEMPS IN THE LOW-MID 70S AWAY FROM THE S
COAST...WHERE ONSHORE SLY FLOW WILL KEEP THINGS COOLER. SHOULD THE
STRATUS DISSIPATE FROM S TO N...OR EVEN A BIT IN THE E THANKS TO
STRONGER SUBSIDENCE...HIGHS MAY NEED TO BE RAISED SOMEWHAT FROM
CURRENT FORECAST.
THE KEY WITH ANY PRECIP WILL BE IN WHAT...IF ANY OF THE MODEST
INSTABILITY IS ABLE TO BE TAPPED. THE COMBINATION OF THE
INCREASING DWPTS AND WARMING SFC TEMPS MAY ALLOW FOR MODEST SB
CAPE VALUES GENERALLY 200J/KG OR LESS...BUT SHOULD THE STRATUS
HOLD LONGER IT WOULD LIKELY TO BE LESS. WITH THE WARM FRONT MOVING
INTO NRN NEW ENGLAND...MOST OF THE AVAILABLE FORCING IS WELL W
ALSO...SO WILL REALLY NEED TO WATCH THE AREAS IN NY/PA FOR ANY
CONVECTIVE DEVELOPMENT WHICH MAY SPILL INTO THE WRN REACHES OF SRN
NEW ENGLAND. HAVE CAPPED POPS AT CHANCE MAINLY FROM ABOUT THE CT
VALLEY INTO THE BORDER WITH ALY. GIVEN THE MODEST INSTABILITY
CONTINUE TO KEEP TS OUT OF THE WX...BUT AS MENTIONED
ABOVE...SHOULD MORE BREAKS OF SUN OCCUR...DESTABILIZATION MAY BE
UNDERESTIMATED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
TONIGHT...
ANY CONVECTION OR -SHRA ACTIVITY SHOULD DIMINISH WITH LOSS OF
DIURNAL HEATING GIVEN THE MODEST INSTABILITY AVAILABLE.
OTHERWISE...SIMILAR SETUP TO WED NIGHT AS SLY FLOW SHOULD ALLOW
FOR ANOTHER ROUND OF STRATUS TO DEVELOP AND BUILD N ESPECIALLY
ACROSS INTERIOR SRN NEW ENGLAND. A LOOK AT MODEL SOUNDINGS SUGGEST
A BIT MORE NEAR SFC MOISTURE HOWEVER...SUGGESTING THE POSSIBILITY
OF A LITTLE MORE LOCALIZED FOG DEVELOPMENT. DON/T CURRENTLY HAVE
ENOUGH CONFIDENCE IN ANY DENSE FOG GIVEN THE DAYTIME MIXING MAY
ACTUALLY KEEP OVERNIGHT DWPTS IN THE UPPER 50S...BUT THIS MAY NEED
TO BE WATCHED. WILL KEEP ANOTHER ROUND OF LOW CLOUDS...FOG AND DZ
THANKS TO THE TRAPPED MOISTURE. MINS ARE LIKELY TO REMAIN
MILD...ONLY FALLING BACK INTO THE UPPER 50S AND LOW 60S.
FRI...
A SECONDARY FRONTAL WAVE WILL BE SLIDING ALONG A SLOW MOVING
FRONTAL BOUNDARY TO THE W. THIS SHOULD ALLOW FOR ONE MORE SHOT OF
MESOSCALE RIDGING WITHIN THE WARM SECTOR ACROSS THE AREA FOR THE
EARLY HALF OF THE DAY ON FRI. THEREFORE...THE PRIMARY ISSUE WILL
BE DEALING WITH LEFTOVER FOG/STRATUS TO START THE DAY...WHICH WILL
LIKELY KEEP HIGHS A BIT LOWER THAN THEIR POTENTIAL ONCE
AGAIN...MAINLY IN THE UPPER 60S AND LOW 70S. BY AFTERNOON...MAY
START TO SEE ENOUGH SUNNY BREAKS TO YIELD MODEST INSTABILITY AHEAD
OF THE APPROACHING FRONT. SO WILL GRADUALLY INCREASE POPS FROM W
TO E AND INTRODUCE SOME TS /MAINLY ISOLATED FOR NOW/. MAIN ISSUE
WOULD BE SOME BRIEF HEAVY RAIN GIVEN HIGH PWATS OF 1.5+ INCHES
/NEARLY 3 STD DEV FROM NORMAL/. HOWEVER...THE MAIN BULK OF THE
PRECIP WILL LIKELY HOLD OFF UNTIL LATE EVENING HOURS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
BIG PICTURE...
DEEP TROUGH CENTERED OVER THE GREAT LAKES WILL DOMINATE THE
EASTERN USA THIS WEEKEND. ANOTHER TROUGH MOVES ASHORE OVER THE
WESTERN USA AND NUDGES THE WEATHER SYSTEMS EAST A LITTLE. BUT AS
THE EASTERN TROUGH MOVES TO NEW ENGLAND IT WILL DRAW A CLOSED LOW
WEST FROM THE ATLANTIC OCEAN...WITH THE TWO SYSTEMS MERGING INTO A
CLOSED LOW OVER SOUTHERN NEW ENGLAND THAT LINGERS OVERHEAD MONDAY
THROUGH WEDNESDAY. COLD AIR ALOFT /COLD POOL/ WILL MOVE IN WITH
THE UPPER LOW AND REMAIN OVERHEAD THROUGH MIDWEEK. THE APPROACH OF
THE TROUGH PROMISES A PERIOD OF SHOWERS FRIDAY-SATURDAY WITH MILD
TEMPS. THE SUBSEQUENT UPPER LOW OVERHEAD WILL MEAN INSTABILITY
CLOUDS/SHOWERS AND COOLER TEMPS EARLY NEXT WEEK.
THE DAILIES...
FRIDAY NIGHT AND SATURDAY...UPPER FLOW IS SOUTH TO NORTH AND SO IT
WILL OPPOSE ANY FAST MOVEMENT OF WEATHER FEATURES TOWARD THE EAST.
STRONGEST LOW LEVEL JET WINDS /40 TO 50 KNOTS/ MOVE OVER NEW ENGLAND
DURING THIS PERIOD WITH THE SURFACE COLD FRONT REACHING THE HUDSON
VALLEY AROUND MIDNIGHT AND SLOWLY CROSSING SOUTHERN NEW ENGLAND
DURING SATURDAY/SAT NIGHT. THE STRONG LOW LEVEL JET ADVECTS 1.5 INCH
PCPBL WATER VALUES...2 STD DEV ABOVE NORMAL...AND GENERATES
ISENTROPIC LIFT. THIS WILL BE JOINED WITH THE RIGHT-ENTRANCE REGION
OF THE UPPER JET DURING THIS PERIOD. STRONG LIFT AND ABUNDANT
MOISTURE POINT TO THIS AS BEING THE PERIOD OF HEAVIEST
RAINFALL...WITH OVERALL AMOUNTS OF 1.0 TO 1.5 INCHES COMMON AND
LOCALLY HIGHER AMOUNTS AT OR ABOVE 2 INCHES LIKELY. HEAVIEST AMOUNTS
ARE FAVORED IN WESTERN NEW ENGLAND...THE PCPN IS LONGEST IN DURATION
THERE AND THAT AREA IS CLOSEST TO THE RIGHT ENTRANCE REGION/UPPER
VENTING. IN ADDITION...THERE WILL BE MARGINAL AND ELEVATED
INSTABILITY WITH TOTALS IN THE MID TO UPPER 40S. THIS WILL
CONTRIBUTE A POTENTIAL FOR SOME WIDELY SCATTERED THUNDER.
SUNDAY THROUGH WEDNESDAY... THE FRONT MOVES OFF...SLOWLY...BUT THE
DEVELOPING CLOSED UPPER LOW WILL MOVE OVER NEW ENGLAND AND TAKE UP
RESIDENCE FOR A FEW DAYS. IT WILL DRAW IN COLDER AIR AT MID
LEVELS...ESPECIALLY MONDAY THROUGH WEDNESDAY. COLD ADVECTION
ALOFT WILL CREATE 850-500 MB LAPSE RATES EITHER SIDE OF 7C/KM AND
TOTALS OF 50-55 ESPECIALLY ON MONDAY-TUESDAY-WEDNESDAY. COLD POOL
CLOUDS WILL DOMINATE EACH DAY WITH SUFFICIENT INSTABILITY FOR
SCATTERED SHOWERS/TSTMS.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
TODAY...HIGH CONFIDENCE IN TRENDS BUT LOWER CONFIDENCE IN
TIMING. THE MORNING STARTS WITH VFR OVER THE CAPE AND
ISLANDS...3000-3500 FOOT CIGS OVER RI AND SOUTHEAST
MASS...2000-3000 FOOT CIGS BOSTON METRO NORTH AND WEST...IFR OR
LOW-END MVFR CIGS MHT-ORH-IJD AND POINTS WEST. EXPECT AN IMPROVING
TREND THROUGH THE MORNING WITH VFR EAST OF WORCESTER AND MVFR CIGS
WEST. LOW PROBABILITY OF AN AFTERNOON/EVENING -SHRA IN THE WEST.
A FEW S WIND GUSTS TO 20 KT DURING THE DAY...ESPECIALLY IF THE SUN
BREAKS OUT.
TONIGHT INTO FRI...MODERATE CONFIDENCE.
ANY AREAS NOT ALREADY MVFR ARE EXPECTED TO ONCE AGAIN DETERIORATE
TO MVFR IN LOW CIGS AND MORE WIDESPREAD FOG. SOME IFR ALSO
POSSIBLE. DURING THE DAY FRI...SOME IMPROVEMENT TO VFR POSSIBLE
ESPECIALLY ERN MA AND RI...BUT LOW CLOUDS AND FOG MAY LINGER IN
THE INTERIOR. OTHERWISE...TOWARD EVENING EXPECT A RETURN TO
MVFR/IFR EVERYWHERE IN LOW CIGS...RAIN AND FOG...ESPECIALLY BY FRI
NIGHT. SOME SOUTHERLY WIND GUSTS UP TO 25 KT POSSIBLE.
KBOS TERMINAL...HIGH CONFIDENCE IN OVERALL TRENDS...LOWER
CONFIDENCE IN TIMING OF MID MORNING IMPROVEMENT. CIGS MAY BOUNCE
BETWEEN MVFR AND LOW-END VFR DURING MID MORNING.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS...LOWER CONFIDENCE
IN EXACT TIMING.
OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE.
FRIDAY NIGHT THROUGH SATURDAY...WIDESPREAD IFR IN SHOWERS AND FOG.
SCATTERED TSTMS AND LOCALLY HEAVY DOWNPOURS. HEAVIEST PCPN IN THE CT
VALLEY WILL BE ROUGHLY MIDNIGHT TO DAWN/IN THE CENTRAL HILLS 3 AM TO
MID MORNING/COASTAL PLAIN DAWN TO MIDDAY. STRONG SOUTH TO SOUTHEAST
WINDS AT 2000 FEET AGL WITH SPEEDS 40 TO 50 KNOTS. THIS WILL MEAN
LOW LEVEL WIND SHEAR.
SUNDAY-MONDAY... VFR WITH MVFR CIGS/VSBYS IN SCATTERED SHOWERS AND
ISOLATED TSTMS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY NIGHT/...HIGH CONFIDENCE.
TODAY... MAINLY QUIET BOATING WEATHER TODAY AS HIGH PRES
CONTINUES SLOW MOVEMENT OFFSHORE. ANY REMAINING SE WINDS SHOULD
SHIFT TO THE S THIS MORNING.
TONIGHT INTO FRI...
WITH PERSISTENT SOUTHERLY WINDS...EXPECT A S SWELL TO DEVELOP
ACROSS THE SRN WATERS TONIGHT...BUILDING INTO FRI. SMALL CRAFT
ADVISORIES HAVE BEEN ISSUED FOR TONIGHT ACROSS THE S...AND ARE
LIKELY TO BE EXPANDED INTO THE E FOR FRI. WINDS MAY COME CLOSE TO
BREAK 25 KT NEAR SHORE DURING THE DAY ON FRI...BUT THE STRONGEST
WINDS ARE LIKELY TO HOLD OFF ACROSS THE WATERS UNTIL FRI NIGHT.
WILL NEED TO WATCH FOR MORE FOG AND LOW VSBYS OVERNIGHT TONIGHT.
OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE
FRIDAY NIGHT AND SATURDAY...COLD FRONT APPROACHES FROM NEW YORK WITH
STRONG WINDS ABOVE THE OCEAN SURFACE...ENOUGH TO SUPPORT 25-30 KNOT
WINDS AT THE SURFACE. SEAS CONTINUE TO BUILD WITH HEIGHTS 5 FEET OR
HIGHER ON ALL EXPOSED WATERS. REDUCED VSBYS IN SCATTERED TSTMS AND
HEAVY DOWNPOURS. WINDS AND SEAS WILL DIMINISH SATURDAY EVENING AND
NIGHT. SMALL CRAFT HEADLINES WILL CONTINUE ON MOST WATERS. THERE IS
A LOW CHANCE OF SOUTH GALES.
SUNDAY-MONDAY.. WINDS AND SEAS CONTINUE TO DIMINISH BOTH DAYS. WINDS
WILL BE EAST TO NORTHEAST ON THE WATERS EAST OF MASS...AND NORTHWEST
ON THE WATERS SOUTH OF NEW ENGLAND. SPEEDS WILL BE AT OR BELOW 15
KNOTS. SEAS ON THE OUTER WATERS WILL BE 5-6 FEET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 8 PM EDT FRIDAY
FOR ANZ255-256.
SMALL CRAFT ADVISORY FROM 6 AM TO 8 PM EDT FRIDAY FOR ANZ235-
237.
&&
$$
SYNOPSIS...WTB/DOODY
NEAR TERM...WTB/DOODY
SHORT TERM...DOODY
LONG TERM...WTB
AVIATION...WTB/DOODY
MARINE...WTB/DOODY
AREA FORECAST DISCUSSION
NWS MIAMI FL
752 AM EDT THU MAY 15 2014
.AVIATION...
CURRENTLY MOST OF THE SHOWER ACTIVITY IS OVER THE ATLANTIC WATERS
WITH NO LIGHTNING NOTED. THE COMBINATION OF EXTENSIVE CLOUD COVER
CURRENTLY ACROSS THE REGION AND UNFAVORABLE ATMOSPHERIC DYNAMICS
WILL TEND TO INHIBIT THUNDERSTORMS THIS MORNING. HOWEVER...GIVEN
SOME UNCERTAINTY VCTS ASSIGNED ALL TERMINALS AROUND 17Z ALTHOUGH
CONFIDENCE IS LOW WITH MAINLY SHOWER ACTIVITY AND ISOLATED
THUNDERSTORMS EXPECTED THIS AFTERNOON. THERE COULD BE BRIEF
PERIODS OF IFR CONDITIONS WITH THE OCCURRENCE OF SHOWERS OR
THUNDERSTORMS AND WILL AMEND AS NEEDED.
60
&&
.PREV DISCUSSION... /ISSUED 305 AM EDT THU MAY 15 2014/
SHORT TERM (TODAY-SATURDAY)...
THE WEAK MID LEVEL TROUGH THAT MOVED CLOSE TO SOUTH FLORIDA
YESTERDAY BECAME ABSORBED WITH THE VERY IMPRESSIVE TROUGH
DEEPENING ACROSS EASTERN NORTH AMERICA. THIS ENDED UP NOT COOLING
THE UPPER LEVELS MUCH WITH DAYTIME CONVECTION AT A MINIMUM. THE
UPSTREAM TROUGH WILL BE SHIFTING EAST TODAY IN RESPONSE TO A LARGE
RIDGE AMPLIFLYING OFF THE COAST OF CALIFORNIA. AS THE TROUGH MOVES
EAST, A BAND OF DEEP LAYER MOISTURE WILL MOVE ACROSS THE FLORIDA
PENINSULA AND FORECAST SOUNDINGS SHOW PWAT INCREASING TO NEAR TWO
INCHES BY MIDDAY TODAY. HOWEVER, MID LEVEL LAPSE RATES ARE NOT
LOOKING VERY FAVORABLE FOR STRONG UPDRAFTS DEVELOPING WITH CAPE AT
GENERALLY LESS THAN 1000 J/KG SO ONLY ISOLATED THUNDERSTORMS ARE
EXPECTED. THE SURFACE RIDGE WILL ALSO SHIFT TO THE SOUTH AS A COLD
FRONT ASSOCIATED WITH THE UPSTREAM TROUGH MOVES INTO NORTH FLORIDA
THIS MORNING. A DEEP SOUTHWEST FLOW WILL THEN ENSUE ACROSS SOUTH
FLORIDA SO THE HIGHEST POPS WILL BE ALONG THE EASTERN HALF OF THE
REGION. DUE TO THE DEEPNESS OF THE UPPER TROUGH, THE COLD FRONT
WILL NOT BE A FAST MOVER BUT WILL BE APPROACHING THE WEST COAST BY
THIS AFTERNOON. THE GREATEST POTENTIAL FOR THUNDERSTORMS WILL
LIKELY BE LATE THIS AFTERNOON NEAR THE EAST COAST AS CONVECTION
BEGINS TO DEVELOP OVER THE INTERIOR AND MOVES TOWARDS THE EAST.
THE GLOBAL MODELS ARE ALL IN GOOD AGREEMENT THAT THE SURFACE WIND
WILL REMAIN SOUTH SOUTHEAST THROUGH MUCH OF THE DAY ALONG THE EAST
COAST AND THIS COULD AID IN SOME VERTICAL DEVELOPMENT. HOWEVER,
WITH THE WEAK MID LEVEL LAPSE RATES THE CONVECTION WILL STILL LACK
ROBUST UPLIFT BUT THE STRONGER STORMS WILL BE CAPABLE OF PRODUCING
SOME GUSTY WINDS. THE LOCALLY RUN HIGH RESOLUTION WRF SHOWS THIS
SCENARIO WITH CONVECTION MOVING OFF THE SOUTHEAST COAST EARLY THIS
EVENING AND THEN SCATTERED SHOWERS AHEAD OF THE FRONT THROUGH THE
NIGHT. THE HRRR AS OF THIS WRITING ONLY GOES OUT TO 19Z BUT ALSO SHOWS
NUMEROUS SHOWERS DEVELOPING ACROSS THE INTERIOR AFTER 17Z AND
MOVING TOWARDS THE EAST.
THE NAM, GFS AND ECMWF ARE NOW SHOWING THE COLD FRONT MOVING OFF
THE SOUTHEAST COAST BY 12Z FRIDAY WITH SOME LINGERING MOISTURE
BEHIND THE FRONT UNTIL LATE IN THE AFTERNOON. A MUCH DRIER AIRMASS
WILL THEN FILTER DOWN THE PENINSULA BEHIND THE FRONT WITH SURFACE
HIGH PRESSURE BUILDING ACROSS NORTH FLORIDA. FORECAST SOUNDINGS
FROM ALL OF THE GLOBAL MODELS ARE SHOWING PWAT DROPPING TO AROUND
ONE-HALF INCH AND IF THIS VERIFIES WOULD BE SOME OF THE DRIEST
AIR FOR MAY IN SOUTH FLORIDA SINCE 1948. THE WEEKEND WILL BE DRY
WITH MINIMUM TEMPERATURES SATURDAY MORNING RANGING FROM THE UPPER
50S WEST OF LAKE OKEECHOBEE TO THE MID AND UPPER 60S ALONG BOTH
COASTS WHICH ARE FIVE TO TEN DEGREES BELOW THE AVERAGE. THE LOWS
SUNDAY MORNING WILL ONLY BE A COUPLE OF DEGREES WARMER.
LONG TERM (SUNDAY-WEDNESDAY)...
THE EXTENDED PERIOD WILL REMAIN DRY WITH A LARGE AMPLIFIED MID LEVEL
RIDGE DEVELOPING OVER THE GULF OF MEXICO KEEPING SOUTH FLORIDA UNDER
THE INFLUENCE OF A DRY NORTHWESTERLY FLOW ALOFT. THIS PATTERN WILL
PERSIST THROUGH THE MIDDLE OF NEXT WEEK.
MARINE...
A MODERATE SOUTH SOUTHEAST WIND IS EXPECTED TODAY SLOWLY VEERING
TO THE SOUTHWEST THIS AFTERNOON AND THEN SHIFTING TO THE
NORTHWEST TO NORTH ON FRIDAY BEHIND THE LATE SEASON COLD FRONT.
THE WIND WILL ALSO INCREASE FRIDAY INTO SATURDAY AS THE PRESSURE
GRADIENT TIGHTENS WITH THE STRONG HIGH PRESSURE BUILDING OVER
NORTH FLORIDA AND THE ATLANTIC. AS A RESULT, SEAS WILL BUILD OVER
THE OFFSHORE GULF WATERS AND THE GULF STREAM IN THE ATLANTIC TO
POSSIBLE SCA CRITERIA. WIND AND SEAS WILL SLOWLY SUBSIDE LATER
THIS WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 85 72 81 68 / 70 50 20 10
FORT LAUDERDALE 86 74 83 69 / 70 60 30 10
MIAMI 85 73 83 68 / 70 50 30 10
NAPLES 85 71 82 64 / 60 40 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....23/SK
AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
305 AM EDT THU MAY 15 2014
.SHORT TERM (TODAY-SATURDAY)...
THE WEAK MID LEVEL TROUGH THAT MOVED CLOSE TO SOUTH FLORIDA
YESTERDAY BECAME ABSORBED WITH THE VERY IMPRESSIVE TROUGH
DEEPENING ACROSS EASTERN NORTH AMERICA. THIS ENDED UP NOT COOLING
THE UPPER LEVELS MUCH WITH DAYTIME CONVECTION AT A MINIMUM. THE
UPSTREAM TROUGH WILL BE SHIFTING EAST TODAY IN RESPONSE TO A LARGE
RIDGE AMPLIFLYING OFF THE COAST OF CALIFORNIA. AS THE TROUGH MOVES
EAST, A BAND OF DEEP LAYER MOISTURE WILL MOVE ACROSS THE FLORIDA
PENINSULA AND FORECAST SOUNDINGS SHOW PWAT INCREASING TO NEAR TWO
INCHES BY MIDDAY TODAY. HOWEVER, MID LEVEL LAPSE RATES ARE NOT
LOOKING VERY FAVORABLE FOR STRONG UPDRAFTS DEVELOPING WITH CAPE AT
GENERALLY LESS THAN 1000 J/KG SO ONLY ISOLATED THUNDERSTORMS ARE
EXPECTED. THE SURFACE RIDGE WILL ALSO SHIFT TO THE SOUTH AS A COLD
FRONT ASSOCIATED WITH THE UPSTREAM TROUGH MOVES INTO NORTH FLORIDA
THIS MORNING. A DEEP SOUTHWEST FLOW WILL THEN ENSUE ACROSS SOUTH
FLORIDA SO THE HIGHEST POPS WILL BE ALONG THE EASTERN HALF OF THE
REGION. DUE TO THE DEEPNESS OF THE UPPER TROUGH, THE COLD FRONT
WILL NOT BE A FAST MOVER BUT WILL BE APPROACHING THE WEST COAST BY
THIS AFTERNOON. THE GREATEST POTENTIAL FOR THUNDERSTORMS WILL
LIKELY BE LATE THIS AFTERNOON NEAR THE EAST COAST AS CONVECTION
BEGINS TO DEVELOP OVER THE INTERIOR AND MOVES TOWARDS THE EAST.
THE GLOBAL MODELS ARE ALL IN GOOD AGREEMENT THAT THE SURFACE WIND
WILL REMAIN SOUTH SOUTHEAST THROUGH MUCH OF THE DAY ALONG THE EAST
COAST AND THIS COULD AID IN SOME VERTICAL DEVELOPMENT. HOWEVER,
WITH THE WEAK MID LEVEL LAPSE RATES THE CONVECTION WILL STILL LACK
ROBUST UPLIFT BUT THE STRONGER STORMS WILL BE CAPABLE OF PRODUCING
SOME GUSTY WINDS. THE LOCALLY RUN HIGH RESOLUTION WRF SHOWS THIS
SCENARIO WITH CONVECTION MOVING OFF THE SOUTHEAST COAST EARLY THIS
EVENING AND THEN SCATTERED SHOWERS AHEAD OF THE FRONT THROUGH THE
NIGHT. THE HRRR AS OF THIS WRITING ONLY GOES OUT TO 19Z BUT ALSO SHOWS
NUMEROUS SHOWERS DEVELOPING ACROSS THE INTERIOR AFTER 17Z AND
MOVING TOWARDS THE EAST.
THE NAM, GFS AND ECMWF ARE NOW SHOWING THE COLD FRONT MOVING OFF
THE SOUTHEAST COAST BY 12Z FRIDAY WITH SOME LINGERING MOISTURE
BEHIND THE FRONT UNTIL LATE IN THE AFTERNOON. A MUCH DRIER AIRMASS
WILL THEN FILTER DOWN THE PENINSULA BEHIND THE FRONT WITH SURFACE
HIGH PRESSURE BUILDING ACROSS NORTH FLORIDA. FORECAST SOUNDINGS
FROM ALL OF THE GLOBAL MODELS ARE SHOWING PWAT DROPPING TO AROUND
ONE-HALF INCH AND IF THIS VERIFIES WOULD BE SOME OF THE DRIEST
AIR FOR MAY IN SOUTH FLORIDA SINCE 1948. THE WEEKEND WILL BE DRY
WITH MINIMUM TEMPERATURES SATURDAY MORNING RANGING FROM THE UPPER
50S WEST OF LAKE OKEECHOBEE TO THE MID AND UPPER 60S ALONG BOTH
COASTS WHICH ARE FIVE TO TEN DEGREES BELOW THE AVERAGE. THE LOWS
SUNDAY MORNING WILL ONLY BE A COUPLE OF DEGREES WARMER.
.LONG TERM (SUNDAY-WEDNESDAY)...
THE EXTENDED PERIOD WILL REMAIN DRY WITH A LARGE AMPLIFIED MID LEVEL
RIDGE DEVELOPING OVER THE GULF OF MEXICO KEEPING SOUTH FLORIDA UNDER
THE INFLUENCE OF A DRY NORTHWESTERLY FLOW ALOFT. THIS PATTERN WILL
PERSIST THROUGH THE MIDDLE OF NEXT WEEK.
&&
.MARINE...
A MODERATE SOUTH SOUTHEAST WIND IS EXPECTED TODAY SLOWLY VEERING
TO THE SOUTHWEST THIS AFTERNOON AND THEN SHIFTING TO THE
NORTHWEST TO NORTH ON FRIDAY BEHIND THE LATE SEASON COLD FRONT.
THE WIND WILL ALSO INCREASE FRIDAY INTO SATURDAY AS THE PRESSURE
GRADIENT TIGHTENS WITH THE STRONG HIGH PRESSURE BUILDING OVER
NORTH FLORIDA AND THE ATLANTIC. AS A RESULT, SEAS WILL BUILD OVER
THE OFFSHORE GULF WATERS AND THE GULF STREAM IN THE ATLANTIC TO
POSSIBLE SCA CRITERIA. WIND AND SEAS WILL SLOWLY SUBSIDE LATER
THIS WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 85 72 81 68 / 70 50 20 10
FORT LAUDERDALE 86 74 83 69 / 70 60 30 10
MIAMI 85 73 83 68 / 70 50 30 10
NAPLES 85 71 82 64 / 60 40 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....30/KOB
AREA FORECAST DISCUSSION
NWS MIAMI FL
141 AM EDT THU MAY 15 2014
.AVIATION...
AN ACTIVE TAF PERIOD IS IN STORE FOR SOUTH FLORIDA. ACTIVITY AHEAD
OF A COLD FRONT IS ALREADY PICKING UP WITH NUMEROUS SHOWERS AND A
FEW THUNDERSTORMS STREAMING INTO THE AREA FROM THE ATLANTIC AND
SOON THE GULF. THIS ACTIVITY MAY QUELL FOR A WHILE LATER THIS
MORNING, BUT HAVE JUST KEPT SHRA IN AS PREDOMINATE FOR THE TIME
BEING. THEN TOMORROW, AS THE FRONT GETS CLOSER, THERE IS A HIGH
PROBABILITY OF RAIN SHOWERS THROUGH MUCH OF THE DAY AND INTO THE
EVENING. THERE IS ALSO A CHANCE OF THUNDERSTORM ACTIVITY, THUS A
PROB 30 GROUP AT EACH SITE FROM 18Z THROUGH 00Z. WINDS ARE ALREADY
BEGINNING TO TURN MORE SOUTHERLY TONIGHT AND SHOULD NOT BE QUITE
AS STRONG AS THEY HAVE BEEN OVER THE LAST SEVERAL DAYS. OF COURSE,
THIS IS NOT INCLUDING GUSTY WINDS INVOF TS. THE FRONT WILL
APPROACH THE AREA THIS EVENING AND EVENTUALLY TURN THE WINDS NW
LATER TONIGHT, AS IT MOVES THROUGH.
&&
.PREV DISCUSSION... /ISSUED 822 PM EDT WED MAY 14 2014/
UPDATE 3...
A FEW SHOWERS HAVE DEVELOPED OVER THE SOUTH FLORIDA ATLANTIC
WATERS THIS EVENING. THE SHOWERS SHOULD CONTINUE TO DEVELOP ALONG
WITH A FEW THUNDERSTORMS THROUGH REST OF THE NIGHT AND PUSH
WESTWARD INTO SOUTH FLORIDA...AS THE MID TO UPPER LEVEL THROUGH
OF LOW PRESSURE MOVES THROUGH SOUTH FLORIDA. SO WILL CONTINUE TO
SHOW AN INCREASE IN POPS THROUGH THE NIGHT ACROSS SOUTH FLORIDA
WITH EVEN A SLIGHT CHANCE OF STORMS OVER THE EAST COAST METRO
AREAS. THEREFORE...NO CHANGES TO THE LAST UPDATE EARLIER THIS
EVENING.
UPDATE 3...54/BNB
PREV DISCUSSION... /ISSUED 537 PM EDT WED MAY 14 2014/
UPDATE 2...
THE SHOWERS AND THUNDERSTORMS HAVE DISSIPATED OVER THE EASTERN
AREAS OF SOUTH FLORIDA EARLY THIS EVENING...AS THE EAST COAST SEA
BREEZE HAS PUSHED INLAND. THE SHOWERS AND THUNDERSTORMS OVER THE
WESTERN AREAS OF SOUTH FLORIDA WILL ALSO SLOWLY DISSIPATE THROUGH
THE EVENING HOURS..AS THE HEATING OF THE DAY IS LOST. SO HAVE
LOWER THE POPS DOWN TO SLIGHT CHANCE OVER THE EASTERN AREAS OF
SOUTH FLORIDA AND LOW CHANCE CAT FOR THE WESTERN AREAS OF SOUTH
FLORIDA FOR THE EVENING HOURS.
THE SHORT RANGE MODELS CONTINUE TO SHOW THE MID TO UPPER LEVEL
TROUGH OF LOW PRESSURE OVER THE BAHAMA ISLANDS TO MOVE NORTHWEST
AND THROUGH SOUTH FLORIDA LATE TONIGHT INTO THURSDAY MORNING. THIS
WILL BRING BACK SOME DEEPER TROPICAL MOISTURE TO THE AREA STARTING
LATE TONIGHT. SO WILL SHOW A UP TREND IN POPS STARTING LATE
TONIGHT INTO THURSDAY MORNING OVER SOUTH FLORIDA.
THE COLD FRONT OVER THE THE SOUTHEASTERN UNITED STATES WILL ALSO
BE MOVING SOUTHWARD TOWARD SOUTH FLORIDA ON THURSDAY. THIS WILL
KEEP THE DEEP TROPICAL MOISTURE IN PLACE FOR THURSDAY AFTERNOON.
THEREFORE...THE LIKELY POPS WILL REMAIN IN PLACE OVER SOUTH
FLORIDA FOR THURSDAY AFTERNOON.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED.
UPDATE 2...54/BNB
PREV DISCUSSION... /ISSUED 410 PM EDT WED MAY 14 2014/
UPDATE...
A QUICK UPDATE TO REMOVE THE THUNDER WORDING FOR THE EAST COAST
METRO AREAS FOR FRIDAY...AS THE COLD FRONT WILL BE SOUTH OF THE
AREA PUSHING THE UNSTABLE AIRMASS TO THE SOUTH. REST OF THE
FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES ARE PLANNED.
UPDATE...54/BNB
PREV DISCUSSION... /ISSUED 253 PM EDT WED MAY 14 2014/
DISCUSSION...
THE GLOBAL MODELS CONTINUE TO INDICATE A SURGE OF MOISTURE
ENTERING THE REGION AND CONTINUING OVER NIGHT WITH RECENT
SATELLITE IMAGERY INDICATING THAT TREND ALREADY UNDERWAY WITH A
SURGE OF CLOUDINESS AND SHOWERS CURRENTLY ENTERING THE ATLANTIC
WATERS WITH WIDESPREAD SHOWERS AND ISOLATE THUNDERSTORMS OCCURRING
ACROSS THE ATLANTIC WATERS AND ACROSS PORTIONS OF THE SOUTH
FLORIDA PENINSULA.
BOTH THE EURO AND GFS MODELS INDICATE A SURGE OF MOISTURE ENTERING
THE REGION TONIGHT WITH PWAT`S FORECAST TO BE AROUND 2 INCHES BY
EARLY THURSDAY MORNING. COVERAGE OF SHOWERS IS FORECAST TO
INCREASE TONIGHT AND THURSDAY WITH MORE NUMEROUS ACTIVITY FORECAST
DURING THIS PERIOD. THE GLOBAL MODELS INDICATE A WEAK MID TO UPPER
LEVEL RIDGE OVER THE REGION TONIGHT WITH DYNAMICAL SUPPORT FOR
THUNDERSTORMS FORECAST TO BE LACKING ALTHOUGH ISOLATED ACTIVITY
IS FORECAST. CURIOUSLY THE HRRR MODEL DID NOT INDICATE INCREASING
CONVECTION WITH THIS DEVELOPING SCENARIO BUT IS CONSIDERED TO BE
THE OUTLIER. BY THURSDAY AFTERNOON DEEP LAYERED MOISTURE IS
FORECAST TO LINGER ACROSS THE REGION AHEAD OF A DEVELOPING COLD
FRONT FORECAST TO BE ENTERING THE EASTERN GULF. LIKELY SHOWERS ARE
INDICATED IN THE FORECAST WITH ONLY ISOLATED THUNDERSTORMS
FORECAST AS DYNAMIC SUPPORT IS FORECAST TO BE LACKING. THE COLD
FRONT IS FORECAST TO LINGER ACROSS THE AREA THURSDAY NIGHT INTO
FRIDAY AND BEGIN EXITING THE REGION ON FRIDAY AFTERNOON WITH A
COOLER AND DRIER AIR MASS FORECAST ACROSS THE AREA INTO THE
UPCOMING WEEKEND.
WITH REGIONAL WINDS IN THE 15 TO 20 KNOT RANGE ACROSS THE
ATLANTIC WATERS EXPECTED TO CONTINUE TONIGHT...A HIGH RISK OF RIP
CURRENTS IS EXPECTED TO CONTINUE ALONG THE ATLANTIC COAST BEACHES
TONIGHT.
MARINE...
A PRE-CAUTIONARY SMALL CRAFT STATEMENT WILL LIKELY CONTINUE FOR
THE LOCAL ATLANTIC WATERS OVER NIGHT WITH WINDS IN THE 15 TO 20
KNOT RANGE EXPECTED TO CONTINUE. WINDS ARE FORECAST TO BE MORE
SOUTHERLY ON THURSDAY AND THEN BECOME MORE WESTERLY THURSDAY
NIGHT INTO FRIDAY. SEAS ARE FORECAST TO APPROACH OR REACH ADVISORY
LEVELS FOR THE ATLANTIC AND GULF WATERS LATER ON FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 73 82 67 / 70 40 30 10
FORT LAUDERDALE 85 74 83 69 / 70 40 30 10
MIAMI 85 73 84 69 / 70 40 30 10
NAPLES 84 72 81 64 / 60 30 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....30/KOB
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
147 PM EDT THU MAY 15 2014
.SYNOPSIS...
ISSUED AT 1051 AM EDT THU MAY 15 2014
A LOW PRESSURE CENTER IN OHIO WILL BE LIFTING NORTHWARD TODAY AS
AN UPPER LEVEL TROUGH MOVES INTO THE REGION. THIS UPPER LEVEL
TROUGH WILL REMAIN IN THE AREA THROUGH SATURDAY KEEPING RAIN
CHANCES AROUND. HIGH TEMPERATURES WILL MAINLY BE IN THE 50S TODAY
WITH SOME OF NORTHWEST OHIO REACHING THE LOWER 60S. LOWS TONIGHT
WILL RANGE FROM THE MIDDLE 30S IN SOUTHERN MICHIGAN TO AROUND 40
NEAR THE OHIO RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EDT THU MAY 15 2014
DESPITE PWAT VALUES NEAR PLUS 2 STANDARD DEVIATIONS ACROSS EASTERN
CWA SEVERAL FACTORS PROVING DELETERIOUS FOR SIGNIFICANT/PERSISTENT
HEAVY RAINFALL EVENT. RELATIVE BREVITY OF MOISTURE PLUME/CONTINUED
DOWNSTREAM FOCUS PER DRY SLOT INTRUSION AS SYSTEM OCCLUSAL COMMENCES
WITH EAST CENTRAL ILLINOIS MID TROPOSPHERIC SHORTWAVE DECAYS IN
DEFERENCE TO ARDENT DIGGING OF NORTHERN MISSISSIPPI VALLEY WAVE.
FURTHERMORE WARM CLOUD DEPTH AOB 10KFT ALONG WITH USUALLY RAPID
VARIANCE AND/OR HIGH VELOCITY OF MESOBEATA ELEMENTS COUNTERING
PRECIPITATION EFFICIENCIES. WITH BEST LOW LEVEL LAPSE RATE PLUME
WELL EAST OF CWA HAVE DROPPED TSRA MENTION THIS MORNING AS FORCED
PARCEL ASCENT REMAINING QUITE ELEVATED ATOP STABILIZED BOUNDARY
LAYER WITH BEST DYNAMICS /STRONGEST 925-8H JET STREAK/ LIFTING
NORTHWARD THROUGH CNTL/ERN OH. DIFFICULT NON DIURNAL TEMPERATURE
TREND ESPECIALLY IN FAR ERN CWA WHERE WARM SECTOR PROXIMITY
REFLECTED THIS AM. FAVORED MODIFICATION OF 3 HOURLY TEMP CURVE
TOWARD HIGHER RES NEAR TERM BLEND TO EXTRACT HIGH/LOW IN NEAR TERM.
CYCLONIC 925 MB FLOW WITH THERMAL CORE ACROSS WRN HALF GREAT LAKES
FAVORS THICK CLOUD COVER AND SIDE MORE PESSIMISTICALLY THAN
NAM/ARW/SREF PROFILES WOULD SUGGEST AND NOTE THAT LATEST RAP BUFKIT
TRENDING TOWARDS MORE STUBBORN STRATOCU INTO LATE AFTERNOON.
UNDERCUTTING SHORTWAVE NEAR MN/IA/SD BORDER TO SLOWLY PROGRESS INTO
NRN IL OVERNIGHT AND INTO NWRN IN BY DAYBREAK WITH SMALL CHANCE SHRA
POPS GIVEN DEEP SURFACE REFLECTION AND CONTD MID TROPOSPHERIC HEIGHT
FALLS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT THU MAY 15 2014
UNSEASONABLY COOL AND SOMEWHAT UNSETTLED WX FRIDAY-SATURDAY WILL
GIVE WAY TO MODERATING TEMPERATURES AND DRY CONDITIONS SUNDAY INTO
EARLY NEXT WEEK...
SHEARING SHORTWAVE EMBEDDED IN SOUTHERN EXTENSION OF A HIGHLY
AMPLIFIED MEAN TROUGH AXIS WILL PIVOT EAST THROUGH THE NORTHERN OH
VALLEY FRIDAY INTO EARLY FRIDAY EVENING. ASSOCIATED LARGE SCALE
ASCENT PER 5-3H Q-VECTOR PROGS, DECENT LOW LEVEL RESPONSE/CONVERGENCE
INTO AT LEAST OUR FAR SOUTHWEST, AND STEEPENING LAPSE RATES THROUGH A
DEEP COLUMN SUPPORTS BUMPING UP POPS A BIT FOR SHOWERS...MAINLY LATE
MORNING-AFTERNOON IN THE SOUTH-SOUTHWEST CLOSER TO JET SUPPORT/WEAK
DEFORMATION WITH SHEARING MID LVL WAVE. OTHERWISE...850 MB TEMPS
NEAR/JUST BELOW FREEZING AND INCREASING CLOUD COVER SHOULD HOLD
HIGHS IN THE 50S FRIDAY (15-20F BELOW NORMAL). CONTINUED TO FAVOR
WARMER RAW GUIDANCE OVER MOS FOR FRIDAY NIGHT MINS GIVEN LINGERING
LOW LEVEL HEIGHT GRADIENT/CLOUDS.
UPPER TROUGH/BROAD CIRCULATION WILL BEGIN TO LIFT/OPEN INTO ONTARIO
AND NORTHERN LAKES BY SATURDAY. WEAK CYCLONIC FLOW ON THE SOUTHERN
FRINGE OF THIS FEATURE AND SOME REMNANT SFC MOISTURE MAY BE ENOUGH
TO TRIGGER A FEW DIURNALLY DRIVEN (AFTN) SHOWERS. OTHERWISE...DEEPER
MIXING/MORE INSOLATION SHOULD SUPPORT HIGHS A LITTLE WARMER INTO THE
UPPER 50S/NEAR 60 SATURDAY. SOME CONCERN FOR PATCHY FROST ACROSS
NORTHERN ZONES SUNDAY MORNING UNDER HIGH PRESSURE/CLEARING SKIES.
QUIET WX WITH TEMPS EVENTUALLY MODERATING BACK CLOSER TO NORMAL IS
EXPECTED SUNDAY INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS IN ON
THE LEADING EDGE OF AN EXPANDING CENTRAL CONUS MID/UPPER LEVEL
RIDGE. NEARING THETA-E RIDGE/INSTABILITY AXIS BRINGS LOW CHANCES FOR
SHOWERS/STORMS BACK INTO THE PICTURE BY MID WEEK AS CONVECTIVELY
INDUCED/ENHANCED WAVES RIDE OVER A PROGGED 588-590DAM LOWER MS
VALLEY 5H RIDGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 131 PM EDT THU MAY 15 2014
THE MAIN UPPER LOW WILL LIFT NORTH ACROSS LOWER MICH INTO UPPER
MICHIGAN TONIGHT AS SUBSIDENCE ASSOCIATED WITH A HIGH PRESSURE
AREA INCREASES OVER THE WESTERN GREAT LAKES REGION. THE AREA OF
RAIN THAT WAS JUST UPSTREAM OVER LAKE MICHIGAN INTO NE IL AND SE
WI HAS ALREADY DISSIPATED GIVEN INCREASE OF DOWNWARD MOTION. A
SECONDARY BUT MUCH WEAKER UPPER LEVEL TROF WILL MOVE ACROSS THE
AREA...AND HELP KEEP SOME VFR CIGS OVER THE AREA. CONDITIONS
SHOULD IMPROVE TO VFR AROUND 00Z...WITH WINDS BECOMING LIGHT AS
THE PRESSURE GRADIENT WEAKENS OVER THE AREA.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...LOTHAMER
SHORT TERM...MURPHY
LONG TERM...STEINWEDEL
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1057 AM EDT THU MAY 15 2014
.SYNOPSIS...
ISSUED AT 1051 AM EDT THU MAY 15 2014
A LOW PRESSURE CENTER IN OHIO WILL BE LIFTING NORTHWARD TODAY AS
AN UPPER LEVEL TROUGH MOVES INTO THE REGION. THIS UPPER LEVEL
TROUGH WILL REMAIN IN THE AREA THROUGH SATURDAY KEEPING RAIN
CHANCES AROUND. HIGH TEMPERATURES WILL MAINLY BE IN THE 50S TODAY
WITH SOME OF NORTHWEST OHIO REACHING THE LOWER 60S. LOWS TONIGHT
WILL RANGE FROM THE MIDDLE 30S IN SOUTHERN MICHIGAN TO AROUND 40
NEAR THE OHIO RIVER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EDT THU MAY 15 2014
DESPITE PWAT VALUES NEAR PLUS 2 STANDARD DEVIATIONS ACROSS EASTERN
CWA SEVERAL FACTORS PROVING DELETERIOUS FOR SIGNIFICANT/PERSISTENT
HEAVY RAINFALL EVENT. RELATIVE BREVITY OF MOISTURE PLUME/CONTINUED
DOWNSTREAM FOCUS PER DRY SLOT INTRUSION AS SYSTEM OCCLUSAL COMMENCES
WITH EAST CENTRAL ILLINOIS MID TROPOSPHERIC SHORTWAVE DECAYS IN
DEFERENCE TO ARDENT DIGGING OF NORTHERN MISSISSIPPI VALLEY WAVE.
FURTHERMORE WARM CLOUD DEPTH AOB 10KFT ALONG WITH USUALLY RAPID
VARIANCE AND/OR HIGH VELOCITY OF MESOBEATA ELEMENTS COUNTERING
PRECIPITATION EFFICIENCIES. WITH BEST LOW LEVEL LAPSE RATE PLUME
WELL EAST OF CWA HAVE DROPPED TSRA MENTION THIS MORNING AS FORCED
PARCEL ASCENT REMAINING QUITE ELEVATED ATOP STABILIZED BOUNDARY
LAYER WITH BEST DYNAMICS /STRONGEST 925-8H JET STREAK/ LIFTING
NORTHWARD THROUGH CNTL/ERN OH. DIFFICULT NON DIURNAL TEMPERATURE
TREND ESPECIALLY IN FAR ERN CWA WHERE WARM SECTOR PROXIMITY
REFLECTED THIS AM. FAVORED MODIFICATION OF 3 HOURLY TEMP CURVE
TOWARD HIGHER RES NEAR TERM BLEND TO EXTRACT HIGH/LOW IN NEAR TERM.
CYCLONIC 925 MB FLOW WITH THERMAL CORE ACROSS WRN HALF GREAT LAKES
FAVORS THICK CLOUD COVER AND SIDE MORE PESSIMISTICALLY THAN
NAM/ARW/SREF PROFILES WOULD SUGGEST AND NOTE THAT LATEST RAP BUFKIT
TRENDING TOWARDS MORE STUBBORN STRATOCU INTO LATE AFTERNOON.
UNDERCUTTING SHORTWAVE NEAR MN/IA/SD BORDER TO SLOWLY PROGRESS INTO
NRN IL OVERNIGHT AND INTO NWRN IN BY DAYBREAK WITH SMALL CHANCE SHRA
POPS GIVEN DEEP SURFACE REFLECTION AND CONTD MID TROPOSPHERIC HEIGHT
FALLS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT THU MAY 15 2014
UNSEASONABLY COOL AND SOMEWHAT UNSETTLED WX FRIDAY-SATURDAY WILL
GIVE WAY TO MODERATING TEMPERATURES AND DRY CONDITIONS SUNDAY INTO
EARLY NEXT WEEK...
SHEARING SHORTWAVE EMBEDDED IN SOUTHERN EXTENSION OF A HIGHLY
AMPLIFIED MEAN TROUGH AXIS WILL PIVOT EAST THROUGH THE NORTHERN OH
VALLEY FRIDAY INTO EARLY FRIDAY EVENING. ASSOCIATED LARGE SCALE
ASCENT PER 5-3H Q-VECTOR PROGS, DECENT LOW LEVEL RESPONSE/CONVERGENCE
INTO AT LEAST OUR FAR SOUTHWEST, AND STEEPENING LAPSE RATES THROUGH A
DEEP COLUMN SUPPORTS BUMPING UP POPS A BIT FOR SHOWERS...MAINLY LATE
MORNING-AFTERNOON IN THE SOUTH-SOUTHWEST CLOSER TO JET SUPPORT/WEAK
DEFORMATION WITH SHEARING MID LVL WAVE. OTHERWISE...850 MB TEMPS
NEAR/JUST BELOW FREEZING AND INCREASING CLOUD COVER SHOULD HOLD
HIGHS IN THE 50S FRIDAY (15-20F BELOW NORMAL). CONTINUED TO FAVOR
WARMER RAW GUIDANCE OVER MOS FOR FRIDAY NIGHT MINS GIVEN LINGERING
LOW LEVEL HEIGHT GRADIENT/CLOUDS.
UPPER TROUGH/BROAD CIRCULATION WILL BEGIN TO LIFT/OPEN INTO ONTARIO
AND NORTHERN LAKES BY SATURDAY. WEAK CYCLONIC FLOW ON THE SOUTHERN
FRINGE OF THIS FEATURE AND SOME REMNANT SFC MOISTURE MAY BE ENOUGH
TO TRIGGER A FEW DIURNALLY DRIVEN (AFTN) SHOWERS. OTHERWISE...DEEPER
MIXING/MORE INSOLATION SHOULD SUPPORT HIGHS A LITTLE WARMER INTO THE
UPPER 50S/NEAR 60 SATURDAY. SOME CONCERN FOR PATCHY FROST ACROSS
NORTHERN ZONES SUNDAY MORNING UNDER HIGH PRESSURE/CLEARING SKIES.
QUIET WX WITH TEMPS EVENTUALLY MODERATING BACK CLOSER TO NORMAL IS
EXPECTED SUNDAY INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS IN ON
THE LEADING EDGE OF AN EXPANDING CENTRAL CONUS MID/UPPER LEVEL
RIDGE. NEARING THETA-E RIDGE/INSTABILITY AXIS BRINGS LOW CHANCES FOR
SHOWERS/STORMS BACK INTO THE PICTURE BY MID WEEK AS CONVECTIVELY
INDUCED/ENHANCED WAVES RIDE OVER A PROGGED 588-590DAM LOWER MS
VALLEY 5H RIDGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 703 AM EDT THU MAY 15 2014
SURFACE LOW CENTER NEAR KDFI AT 11 UTC TO CONTINUE NORTH
NORTHEAST TRACK INTO SOUTHEAST LOWER MICHIGAN BY MID MORNING.
WHILE DRY SLOT HAS ALLOWED RAINFALL RATES TO TAPER...A WELL
MIXED/MOIST RESIDUAL BOUNDARY LAYER WILL CONTINUE WITH CIGS BELOW
FUEL/ALT REQUIREMENTS AND LIKELY INTO IFR RANGE LATER THIS AM.
LOWEST CIGS INVOF KSBN IN PROXIMITY TO WRAPPED MOISTURE AND
ADVANCING DEFORMATION ZONE. TRENDED SLOWER WITH GRADUAL SUBCLOUD
EROSION PER LATEST RAP/06 UTC NAM GUIDANCE...NOW EXPECTED BY LATE
DAY FOR SIG IMPROVEMENT/ABOVE FUELING/ALTERNATE REQUIREMENTS BY
EARLY EVENING AT KFWA AND EARLY TONIGHT AT KSBN.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...LOTHAMER
SHORT TERM...MURPHY
LONG TERM...STEINWEDEL
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
711 AM EDT THU MAY 15 2014
.SYNOPSIS...
ISSUED AT 134 AM EDT THU MAY 15 2014
RAIN WILL GRADUALLY GIVE WAY TO CLOUDY AND COOL TEMPERATURES BY
MID MORNING. A SLOW MOVING UPPER LEVEL LOW CENTER WILL PERSIST
ACROSS THE GREAT LAKES INTO THE WEEKEND. THIS SYSTEM WILL PROVIDE
AN OCCASIONAL LOW CHANCE OF RAIN SHOWERS ALONG WITH CONTINUED COOL
TEMPERATURES INTO THE WEEKEND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EDT THU MAY 15 2014
DESPITE PWAT VALUES NEAR PLUS 2 STANDARD DEVIATIONS ACROSS EASTERN
CWA SEVERAL FACTORS PROVING DELETERIOUS FOR SIGNIFICANT/PERSISTENT
HEAVY RAINFALL EVENT. RELATIVE BREVITY OF MOISTURE PLUME/CONTINUED
DOWNSTREAM FOCUS PER DRY SLOT INTRUSION AS SYSTEM OCCLUSAL COMMENCES
WITH EAST CENTRAL ILLINOIS MID TROPOSPHERIC SHORTWAVE DECAYS IN
DEFERENCE TO ARDENT DIGGING OF NORTHERN MISSISSIPPI VALLEY WAVE.
FURTHERMORE WARM CLOUD DEPTH AOB 10KFT ALONG WITH USUALLY RAPID
VARIANCE AND/OR HIGH VELOCITY OF MESOBEATA ELEMENTS COUNTERING
PRECIPITATION EFFICIENCIES. WITH BEST LOW LEVEL LAPSE RATE PLUME
WELL EAST OF CWA HAVE DROPPED TSRA MENTION THIS MORNING AS FORCED
PARCEL ASCENT REMAINING QUITE ELEVATED ATOP STABILIZED BOUNDARY
LAYER WITH BEST DYNAMICS /STRONGEST 925-8H JET STREAK/ LIFTING
NORTHWARD THROUGH CNTL/ERN OH. DIFFICULT NON DIURNAL TEMPERATURE
TREND ESPECIALLY IN FAR ERN CWA WHERE WARM SECTOR PROXIMITY
REFLECTED THIS AM. FAVORED MODIFICATION OF 3 HOURLY TEMP CURVE
TOWARD HIGHER RES NEAR TERM BLEND TO EXTRACT HIGH/LOW IN NEAR TERM.
CYCLONIC 925 MB FLOW WITH THERMAL CORE ACROSS WRN HALF GREAT LAKES
FAVORS THICK CLOUD COVER AND SIDE MORE PESSIMISTICALLY THAN
NAM/ARW/SREF PROFILES WOULD SUGGEST AND NOTE THAT LATEST RAP BUFKIT
TRENDING TOWARDS MORE STUBBORN STRATOCU INTO LATE AFTERNOON.
UNDERCUTTING SHORTWAVE NEAR MN/IA/SD BORDER TO SLOWLY PROGRESS INTO
NRN IL OVERNIGHT AND INTO NWRN IN BY DAYBREAK WITH SMALL CHANCE SHRA
POPS GIVEN DEEP SURFACE REFLECTION AND CONTD MID TROPOSPHERIC HEIGHT
FALLS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT THU MAY 15 2014
UNSEASONABLY COOL AND SOMEWHAT UNSETTLED WX FRIDAY-SATURDAY WILL
GIVE WAY TO MODERATING TEMPERATURES AND DRY CONDITIONS SUNDAY INTO
EARLY NEXT WEEK...
SHEARING SHORTWAVE EMBEDDED IN SOUTHERN EXTENSION OF A HIGHLY
AMPLIFIED MEAN TROUGH AXIS WILL PIVOT EAST THROUGH THE NORTHERN OH
VALLEY FRIDAY INTO EARLY FRIDAY EVENING. ASSOCIATED LARGE SCALE
ASCENT PER 5-3H Q-VECTOR PROGS, DECENT LOW LEVEL RESPONSE/CONVERGENCE
INTO AT LEAST OUR FAR SOUTHWEST, AND STEEPENING LAPSE RATES THROUGH A
DEEP COLUMN SUPPORTS BUMPING UP POPS A BIT FOR SHOWERS...MAINLY LATE
MORNING-AFTERNOON IN THE SOUTH-SOUTHWEST CLOSER TO JET SUPPORT/WEAK
DEFORMATION WITH SHEARING MID LVL WAVE. OTHERWISE...850 MB TEMPS
NEAR/JUST BELOW FREEZING AND INCREASING CLOUD COVER SHOULD HOLD
HIGHS IN THE 50S FRIDAY (15-20F BELOW NORMAL). CONTINUED TO FAVOR
WARMER RAW GUIDANCE OVER MOS FOR FRIDAY NIGHT MINS GIVEN LINGERING
LOW LEVEL HEIGHT GRADIENT/CLOUDS.
UPPER TROUGH/BROAD CIRCULATION WILL BEGIN TO LIFT/OPEN INTO ONTARIO
AND NORTHERN LAKES BY SATURDAY. WEAK CYCLONIC FLOW ON THE SOUTHERN
FRINGE OF THIS FEATURE AND SOME REMNANT SFC MOISTURE MAY BE ENOUGH
TO TRIGGER A FEW DIURNALLY DRIVEN (AFTN) SHOWERS. OTHERWISE...DEEPER
MIXING/MORE INSOLATION SHOULD SUPPORT HIGHS A LITTLE WARMER INTO THE
UPPER 50S/NEAR 60 SATURDAY. SOME CONCERN FOR PATCHY FROST ACROSS
NORTHERN ZONES SUNDAY MORNING UNDER HIGH PRESSURE/CLEARING SKIES.
QUIET WX WITH TEMPS EVENTUALLY MODERATING BACK CLOSER TO NORMAL IS
EXPECTED SUNDAY INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS IN ON
THE LEADING EDGE OF AN EXPANDING CENTRAL CONUS MID/UPPER LEVEL
RIDGE. NEARING THETA-E RIDGE/INSTABILITY AXIS BRINGS LOW CHANCES FOR
SHOWERS/STORMS BACK INTO THE PICTURE BY MID WEEK AS CONVECTIVELY
INDUCED/ENHANCED WAVES RIDE OVER A PROGGED 588-590DAM LOWER MS
VALLEY 5H RIDGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 703 AM EDT THU MAY 15 2014
SURFACE LOW CENTER NEAR KDFI AT 11 UTC TO CONTINUE NORTH
NORTHEAST TRACK INTO SOUTHEAST LOWER MICHIGAN BY MID MORNING.
WHILE DRY SLOT HAS ALLOWED RAINFALL RATES TO TAPER...A WELL
MIXED/MOIST RESIDUAL BOUNDARY LAYER WILL CONTINUE WITH CIGS BELOW
FUEL/ALT REQUIREMENTS AND LIKELY INTO IFR RANGE LATER THIS AM.
LOWEST CIGS INVOF KSBN IN PROXIMITY TO WRAPPED MOISTURE AND
ADVANCING DEFORMATION ZONE. TRENDED SLOWER WITH GRADUAL SUBCLOUD
EROSION PER LATEST RAP/06 UTC NAM GUIDANCE...NOW EXPECTED BY LATE
DAY FOR SIG IMPROVEMENT/ABOVE FUELING/ALTERNATE REQUIREMENTS BY
EARLY EVENING AT KFWA AND EARLY TONIGHT AT KSBN.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...MURPHY
SHORT TERM...MURPHY
LONG TERM...STEINWEDEL
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
409 AM EDT THU MAY 15 2014
.SYNOPSIS...
ISSUED AT 134 AM EDT THU MAY 15 2014
RAIN WILL GRADUALLY GIVE WAY TO CLOUDY AND COOL TEMPERATURES BY
MID MORNING. A SLOW MOVING UPPER LEVEL LOW CENTER WILL PERSIST
ACROSS THE GREAT LAKES INTO THE WEEKEND. THIS SYSTEM WILL PROVIDE
AN OCCASIONAL LOW CHANCE OF RAIN SHOWERS ALONG WITH CONTINUED COOL
TEMPERATURES INTO THE WEEKEND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM EDT THU MAY 15 2014
DESPITE PWAT VALUES NEAR PLUS 2 STANDARD DEVIATIONS ACROSS EASTERN
CWA SEVERAL FACTORS PROVING DELETERIOUS FOR SIGNIFICANT/PERSISTENT
HEAVY RAINFALL EVENT. RELATIVE BREVITY OF MOISTURE PLUME/CONTINUED
DOWNSTREAM FOCUS PER DRY SLOT INTRUSION AS SYSTEM OCCLUSAL COMMENCES
WITH EAST CENTRAL ILLINOIS MID TROPOSPHERIC SHORTWAVE DECAYS IN
DEFERENCE TO ARDENT DIGGING OF NORTHERN MISSISSIPPI VALLEY WAVE.
FURTHERMORE WARM CLOUD DEPTH AOB 10KFT ALONG WITH USUALLY RAPID
VARIANCE AND/OR HIGH VELOCITY OF MESOBEATA ELEMENTS COUNTERING
PRECIPITATION EFFICIENCIES. WITH BEST LOW LEVEL LAPSE RATE PLUME
WELL EAST OF CWA HAVE DROPPED TSRA MENTION THIS MORNING AS FORCED
PARCEL ASCENT REMAINING QUITE ELEVATED ATOP STABILIZED BOUNDARY
LAYER WITH BEST DYNAMICS /STRONGEST 925-8H JET STREAK/ LIFTING
NORTHWARD THROUGH CNTL/ERN OH. DIFFICULT NON DIURNAL TEMPERATURE
TREND ESPECIALLY IN FAR ERN CWA WHERE WARM SECTOR PROXIMITY
REFLECTED THIS AM. FAVORED MODIFICATION OF 3 HOURLY TEMP CURVE
TOWARD HIGHER RES NEAR TERM BLEND TO EXTRACT HIGH/LOW IN NEAR TERM.
CYCLONIC 925 MB FLOW WITH THERMAL CORE ACROSS WRN HALF GREAT LAKES
FAVORS THICK CLOUD COVER AND SIDE MORE PESSIMISTICALLY THAN
NAM/ARW/SREF PROFILES WOULD SUGGEST AND NOTE THAT LATEST RAP BUFKIT
TRENDING TOWARDS MORE STUBBORN STRATOCU INTO LATE AFTERNOON.
UNDERCUTTING SHORTWAVE NEAR MN/IA/SD BORDER TO SLOWLY PROGRESS INTO
NRN IL OVERNIGHT AND INTO NWRN IN BY DAYBREAK WITH SMALL CHANCE SHRA
POPS GIVEN DEEP SURFACE REFLECTION AND CONTD MID TROPOSPHERIC HEIGHT
FALLS.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT THU MAY 15 2014
UNSEASONABLY COOL AND SOMEWHAT UNSETTLED WX FRIDAY-SATURDAY WILL
GIVE WAY TO MODERATING TEMPERATURES AND DRY CONDITIONS SUNDAY INTO
EARLY NEXT WEEK...
SHEARING SHORTWAVE EMBEDDED IN SOUTHERN EXTENSION OF A HIGHLY
AMPLIFIED MEAN TROUGH AXIS WILL PIVOT EAST THROUGH THE NORTHERN OH
VALLEY FRIDAY INTO EARLY FRIDAY EVENING. ASSOCIATED LARGE SCALE
ASCENT PER 5-3H Q-VECTOR PROGS, DECENT LOW LEVEL RESPONSE/CONVERGENCE
INTO AT LEAST OUR FAR SOUTHWEST, AND STEEPENING LAPSE RATES THROUGH A
DEEP COLUMN SUPPORTS BUMPING UP POPS A BIT FOR SHOWERS...MAINLY LATE
MORNING-AFTERNOON IN THE SOUTH-SOUTHWEST CLOSER TO JET SUPPORT/WEAK
DEFORMATION WITH SHEARING MID LVL WAVE. OTHERWISE...850 MB TEMPS
NEAR/JUST BELOW FREEZING AND INCREASING CLOUD COVER SHOULD HOLD
HIGHS IN THE 50S FRIDAY (15-20F BELOW NORMAL). CONTINUED TO FAVOR
WARMER RAW GUIDANCE OVER MOS FOR FRIDAY NIGHT MINS GIVEN LINGERING
LOW LEVEL HEIGHT GRADIENT/CLOUDS.
UPPER TROUGH/BROAD CIRCULATION WILL BEGIN TO LIFT/OPEN INTO ONTARIO
AND NORTHERN LAKES BY SATURDAY. WEAK CYCLONIC FLOW ON THE SOUTHERN
FRINGE OF THIS FEATURE AND SOME REMNANT SFC MOISTURE MAY BE ENOUGH
TO TRIGGER A FEW DIURNALLY DRIVEN (AFTN) SHOWERS. OTHERWISE...DEEPER
MIXING/MORE INSOLATION SHOULD SUPPORT HIGHS A LITTLE WARMER INTO THE
UPPER 50S/NEAR 60 SATURDAY. SOME CONCERN FOR PATCHY FROST ACROSS
NORTHERN ZONES SUNDAY MORNING UNDER HIGH PRESSURE/CLEARING SKIES.
QUIET WX WITH TEMPS EVENTUALLY MODERATING BACK CLOSER TO NORMAL IS
EXPECTED SUNDAY INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS IN ON
THE LEADING EDGE OF AN EXPANDING CENTRAL CONUS MID/UPPER LEVEL
RIDGE. NEARING THETA-E RIDGE/INSTABILITY AXIS BRINGS LOW CHANCES FOR
SHOWERS/STORMS BACK INTO THE PICTURE BY MID WEEK AS CONVECTIVELY
INDUCED/ENHANCED WAVES RIDE OVER A PROGGED 588-590DAM LOWER MS
VALLEY 5H RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 128 AM EDT THU MAY 15 2014
SURFACE LOW CENTER NEAR KMIE AT 05 UTC TO MOVE NORTH NORTHEAST
INTO SOUTHEAST LOWER MICHIGAN BY 12 UTC. DRY SLOT ALLOWING
RAINFALL RATES TO QUICKLY TAPER. HOWEVER WELL MIXED/MOIST RESIDUAL
BOUNDARY LAYER TO FEATURE CIGS BELOW FUEL/ALT REQUIREMENTS AND
LIKELY SETTLING INTO IFR RANGE LATER THIS AM. GRADUAL SUBCLOUD
EROSION THROUGH THE DAY TO PROVIDE FOR SIG IMPROVEMENT BY EARLY
AFTERNOON.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...MURPHY
SHORT TERM...MURPHY
LONG TERM...STEINWEDEL
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS PADUCAH KY
247 PM CDT Thu May 15 2014
.SHORT TERM...(Tonight through Saturday night)
Issued at 247 PM CDT THU MAY 15 2014
Scattered showers are spreading through southeast Missouri as of
19Z. The mid-level cold pool will be overspreading that area
through the afternoon, so hail will be a concern. 12Z NAM and GFS
soundings do not indicate much instability, so not certain how
much large/severe hail there will be, but will be monitoring closely.
The main mid/upper-level trough will swing through the area
tonight, so showers and a few thunderstorms are likely to persist
through the evening and into the overnight hours. Figure that the
thunder concern will dwindle through the evening. By morning the
convection should be east of the area. However, as the upper low
pushes through Indiana, some scattered showers will be possible
mainly over the Evansville Tri State in the afternoon.
The 12Z NAM and GFS have come into agreement in bringing an band
of showers associated with a disturbance rotating through the base
of the main upper trough. The showers should dive southeast into
southeast Missouri Friday evening, and then eastward along the
Tennessee border overnight and into Saturday morning before
exiting the region. Now have a limited area of likely PoPs for
this event, with a sharp gradient to the north.
A similar scenario is advertised by the models Saturday night, but
this one should stay just south of our area.
Very dry air, dewpoints in the upper 20s, currently over
southeast Kansas, will slide eastward into our region tonight and
Friday. With clear skies and light winds expected across the
northern half of the area Friday night, there will be some
potential for frost formation. Lows in the upper 30s are not out
of the question along and north of Highway 13 and across the
Evansville Tri State. Guidance for KMVN would support middle 30s.
Anyway, will continue to monitor, but a Frost Advisory is
definitely in play Friday night.
As for temperatures, did not stray far from the consensus guidance.
.LONG TERM...(Sunday through Thursday)
Issued at 247 PM CDT THU MAY 15 2014
Models show an upper level ridge building northeast out of Texas
late in the weekend into the middle of next week. At the surface,
low pressure over the Central Plains will lift a warm front across
our region Monday night into Tuesday. GFS lifts the front across us
dry, while ECMWF does generate a few spits of QPF but is trending
drier. Will go for a dry forecast Sunday through Wednesday. ECMWF
tries to break down the upper level ridge late in the extended,
which would allow the front to drift back south, and brings some
light QPF into our northern counties Thursday. GFS keeps the front
well to our north, and thus keeps us dry. Will go with a dry
forecast for now due to the ECMWF trending toward the GFS.
Temperatures will continue to moderate toward seasonal readings
Sunday and Monday. With winds becoming southerly behind the front,
more significant warming is expected Tuesday through Thursday.
Readings will climb back to above seasonal values in the lower to
middle 80s.
&&
.AVIATION...
Issued at 1212 PM CDT THU MAY 15 2014
Latest HRRR guidance confines convection to the western half of
the area late this afternoon and into the evening. Not confident
enough in TS to mention it at any location, but may need to insert
it once the radar lights up. Decided to just TEMPO VFR shra for
now. Guidance does not bring convection to KEVV or KOWB until the
late evening into the overnight hours. Gave those sites a similar
treatment as the western sites. Winds will be generally from the
west aob 10kts this afternoon, and then light overnight. Some
gusts into the teens possible Friday morning.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...RST
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1213 PM CDT Thu May 15 2014
.UPDATE...
Issued at 1212 PM CDT THU MAY 15 2014
Little change to existing forecast planned. 12Z model soundings
not showing much instability, so not sure how much thunder there
will be this afternoon. However, the freezing level may be as low
as 5-6kft AGL, so hail is a good bet out of any storm that develops.
The AVIATION section has been updated for the 18Z TAF issuance.
&&
.SHORT TERM...(Today through Saturday night)
Issued at 255 AM CDT THU MAY 15 2014
Upper trof still to our west. Patches of light rain and drizzle
continue to move across the area. Fog imagery shows decreasing
clouds to our west. Expect a decreasing trend from west to east in
the light rain, drizzle activity through the morning.
Focus this afternoon will be on convective potential. A boundary
is evident in the models sfc/h8 over MO moving toward the area
this afternoon and evening as another lobe of energy rotates toward
the area within the large scale upper trof over the nation`s mid
section. Rather steep lapse rates push east this afternoon upon
< -24 deg C air at h5, causing mid level lapse rates to exceed 7
with total totals into the mid 50s. This coupled with MUCAPEs over
1000 and blayer li`s -2 to -4 should yield low top convection
(EL`s below 30k/ft). Throw in freezing levels below 7k/ft and
h10/h8 and h10/h7 lapse rates exceeding 8, could be some gusty
winds and hail with a few of the storms. Best chance will be SEMO
this afternoon and maybe into west KY and srn IL this evening
before instability diminishes. Chance of showers overnight shifts
to the east part of the CWFA.
Friday, the models spread a wedge of drier air across the CWFA
with better moisture to our NNE and SW. Cannot rule out a few
showers toward the I64 corridor through the day, and maybe into
southern parts of SEMO by afternoon Friday. Friday night through
Saturday, PoPs will be confined to areas mainly along the MO/AR
and TN/KY state lines and just north, as a quick moving wave
brings better rain chances to AR/TN and points south. No PoPs at
this time for Saturday night given ill-defined mid level support
and marginal moisture.
High and low temps will be a blend of the latest MOS and existing
forecast numbers.
.LONG TERM...(Sunday through Wednesday)
Issued at 255 AM CDT THU MAY 15 2014
The extended portion of this forecast issuance is dominated by the
building high pressure ridge aloft and increasing warm air advection
at the surface.
Minor shortwaves will continue to drift southeast along the
northeast edge of the ridge during a brief period on Tuesday, when
the ridge is briefly weakened with the passing shortwaves. However,
any precipitation chances will be limited to the extreme northeast
corner of the WFO PAH CWA and should be minimal in nature.
Given the uncertainty on the depth and coverage of the northwest
flow iteration with the surface ridge, any meaningful PoPs/Weather
have been dropped during the extended forecast period.
With the reduction/elimination of PoP`s, adjusted maximum and
minimum temperatures upward above guidance due to mixing and a sharp
gradient of warm air advection.
&&
.AVIATION...
Issued at 1212 PM CDT THU MAY 15 2014
Latest HRRR guidance confines convection to the western half of
the area late this afternoon and into the evening. Not confident
enough in TS to mention it at any location, but may need to insert
it once the radar lights up. Decided to just TEMPO VFR shra for
now. Guidance does not bring convection to KEVV or KOWB until the
late evening into the overnight hours. Gave those sites a similar
treatment as the western sites. Winds will be generally from the
west aob 10kts this afternoon, and then light overnight. Some
gusts into the teens possible Friday morning.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1142 PM EDT FRI MAY 16 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 323 PM EDT FRI MAY 16 2014
UNSEASONABLY COOL WEATHER WILL CONTINUE THROUGH SATURDAY WITH AREAS
OF FROST EXPECTED OVERNIGHT. SCATTERED RAIN SHOWERS ARE POSSIBLE
SATURDAY ESPECIALLY EAST OF US-131. FAIR WEATHER WILL RETURN SUNDAY
AND MONDAY AND TEMPERATURES WILL UNDERGO A GRADUAL MODERATING TREND
SUNDAY INTO NEXT WEEK. THE NEXT CHANCE FOR SHOWERS AND THUNDERSTORMS
WILL BEGIN TUESDAY NIGHT AND LAST INTO WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 323 PM EDT FRI MAY 16 2014
ISSUED A FROST ADVISORY FOR TONIGHT FOR THE ENTIRE COUNTY WARNING
AREA. THERE IS QUITE A BIT OF UNCERTAINTY TO THE SOUTHEAST WHERE
SOME SHORT RANGE GUIDANCE ADVERTISES LOW LEVEL MOISTURE AND CLOUDS
PERSISTING OVERNIGHT TOWARDS JACKSON. LIGHT RAIN MIGHT EVEN BE IN
PLAY EARLY TONIGHT OVER THIS AREA. HOWEVER...TEND TO FAVOR THE
HI-RES ARW WRF AND RECENT HRRR RUNS WHICH ARE FAIRLY QUICK TO EXIT
PRECIPITATION TO THE EAST WELL BEFORE MIDNIGHT.
DISCUSSED THIS WITH THE DETROIT OFFICE...AND WE AGREE THAT CHANCES
FOR FROST DECREASE AS ONE MOVES EAST TOWARDS THEIR AREA DUE TO
RESIDUAL RAIN/MOIST LOW LEVELS/WET SOIL CONDITIONS THERE. THANKS FOR
COORDINATION DETROIT AND NORTHERN INDIANA.
OTHERWISE...WE EXPECT A GRADUAL WARMUP TO COMMENCE SUNDAY WITH NO
IMPACT WEATHER EXPECTED.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 323 PM EDT FRI MAY 16 2014
A LARGE DOME OF SFC HIGH PRESSURE WILL GRADUALLY DRIFT EAST FROM THE
GREAT LAKES MONDAY AND BE REPLACED BY LOW PRESSURE OVER THE PLAINS.
THE LOW WILL PUSH A WARM FRONT THROUGH LOWER MICHIGAN TUESDAY. THE
TRANSITION TO THE WARM SECTOR WILL PROVIDE A DAY AND A HALF
OPPORTUNITY FOR THUNDERSTORM DEVELOPMENT. THE HIGHEST CHANCE FOR
TSRA DEVELOPMENT WILL COME TUESDAY AFTERNOON THROUGH TUESDAY EVENING
AS THE SFC LOW MAKES A MOVE TOWARD THE CWA. MUCAPES ARE PROGD TO
CLIMB TO AROUND 1K J/KG LATE TUESDAY. IT/S EARLY YET...BUT SHEAR
VALUES PROGD AROUND 50KTS SUGGEST THE POTENTIAL FOR STRONG TO SEVERE
STORMS LATE TUESDAY.
AS THE SFC LOW MOVES THROUGH THE FRONTAL BOUNDARY WILL MOVES SOUTH
AND CHANCES FOR SHOWERS WILL DIMINISH. AFTER MONDAY...HIGHS WILL BE
MOSTLY IN THE 70S NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM EDT FRI MAY 16 2014
VFR CONDITIONS ARE EXPECTED THROUGH SATURDAY NIGHT. MOSTLY LAYERED
MID CLOUDS SHOULD PREVAIL THROUGH SATURDAY AS THE UPPER TROUGH
MOVES THROUGH THE AREA. THERE COULD BE SOME LIGHT RAIN SHOWERS
INLAND OF US-131 SATURDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 323 PM EDT FRI MAY 16 2014
NO HEADLINES EXPECTED IN THE SHORT TERM. WINDS FROM THE SOUTHWEST
WILL RAISE WAVE HEIGHTS SLIGHTLY SATURDAY NIGHT...BUT WE DO NOT
EXPECT SMALL CRAFT ADVISORY CONDITIONS IN THE FORESEEABLE FUTURE.
&&
.HYDROLOGY...
ISSUED AT 323 PM EDT FRI MAY 16 2014
RIVER LEVELS REMAIN ELEVATED IN SOUTHWEST LOWER MICHIGAN... WITH
SYCAMORE CREEK AT HOLT AND THE RED CEDAR RIVER AT EAST LANSING IN
INGHAM COUNTY CURRENTLY ABOVE FLOOD STAGE. SYCAMORE CREEK SHOULD
FALL BELOW FLOOD STAGE THIS EVENING WHILE THE RED CEDAR RIVER SHOULD
DROP BELOW FLOOD STAGE SATURDAY NIGHT. NO OTHER SITES SHOULD REACH
FLOOD STAGE... THOUGH A COUPLE MAY COME CLOSE. LITTLE ADDITIONAL
RAINFALL IS EXPECTED THROUGH TUESDAY. PLEASE REPORT ANY FLOODING TO
THE NATIONAL WEATHER SERVICE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FROST ADVISORY UNTIL 8 AM EDT SATURDAY FOR MIZ037>040-043>046-
050>052-056>059-064>067-071>074.
LM...NONE.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...63
AVIATION...WDM
HYDROLOGY...63
MARINE...TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
654 PM EDT THU MAY 15 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 332 PM EDT THU MAY 15 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
ACRS THE UPR MIDWEST...WITH 00Z-12Z H3 FALLS UP TO 180M...BTWN HI
AMPLITUDE RDG OVER THE W AND ALONG THE E COAST. THERE ARE TWO
SHRTWVS OF SIGNIFICANCE WITHIN THIS TROF. THE FIRST IS LIFTING NNEWD
THRU ERN WI TOWARD CENTRAL UPR MI AND THE SECOND IS DIGGING SEWD
THRU IOWA. DESPITE THE IMPRESSIVE SHARPENING OF THE UPR TROF...WRN
EDGE OF THE DEEPER WARM CONVEYOR BELT MSTR OVER FAR ERN UPR MI HAS
BEEN PUSHING SLOWLY TO THE E AND AWAY FM THE CWA. IN FACT...STLT
IMAGERY SHOWS IMPRESSIVE DRY SLOTTING UP THE LENGTH OF LK MI UNDER
JET SURGE REGION OF SHRTWV NOW LIFTING INTO CENTRAL UPR MI.
THERE IS ANOTHER AREA OF ENHANCED...COLDER CLD TOPS OVER ECENTRAL WI
ON CYC SIDE OF THIS SHRTWV/ASSOCIATED H7 LO AND TO THE E OF THE
OTHER SHRTWV IN IOWA. DESPITE A FAIRLY MOIST LYR BTWN H9-5 SHOWN ON
THE 12Z GRB RAOB...RA UNDER THIS AREA OF ENHANCED CLD HAS BEEN LGT
AND SOMEWHAT SPOTTY. THE PROBLEM APPEARS TO BE DRY LLVL AIR SHOWN ON
THE 12Z MPX/INL RAOBS. SFC DEWPT DEPRESSIONS OVER THE W HALF OF UPR
MI ROSE AS HI AS 15-20F. THE FEED OF THIS LLVL DRY AIR LIMITED THE
EXPANSION OF PCPN TO THE W DESPITE RATHER IMPRESSIVE DEEP LYR QVECTOR
CNVGC ASSOCIATED WITH SHRTWV LIFTING INTO CENTRAL UPR MI.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS/PTYPE ASSOCIATED WITH
PAIR OF SHRTWVS NOTED ABOVE. LACK OF CLEAR PHASING BTWN THESE TWO
SEPARATE DISTURBANCES/AREAS OF DEEPER MSTR/IMPACT OF LLVL DRY AIR
APPEARS TO BE THE CHIEF LIMITING FACTOR ON PRECIP INTENSITY/
COVERAGE.
LATE THIS AFTN/TNGT...GIVEN THE UPR DRY SLOTTING BTWN WARM CONVEYOR
BELT MSTR/SOMEWHAT SHALLOWER MSTR SHOWN ON THE 12Z GRB RAOB AS WELL
AS THE LLVL DRY AIR IN PLACE OVER THE W HALF OF THE CWA/LATEST OBS
WV TRENDS TO THE S...PREFER THE DRIER LOOK OF THE 12Z LOCAL WRF-ARW
MODEL FOR POPS/QPF. THERE WL BE SOME EXPANSION OF THE PRECIP AREA
INTO THIS EVNG OVER THE CENTRAL AND E WITH PASSAGE OF H7 LO OVER
NEWBERRY AND ASSOCIATED BAND OF F85-7 FGEN JUST TO THE W UNDER AREA
OF DEEP LYR QVECTOR CNVGC. BUT PASSAGE OF AREA OF DEEP LYR QVECTOR
CNVGC TO THE N BY 03Z WL DIMINISH ANY HEAVIER MIXED PCPN. UPSLOPE N
WIND WL BRING MORE NMRS SHOWERS TO THE NCENTRAL...ESPECIALLY THE
HIER TERRAIN...BUT OVERALL DRYNESS OF THE LLVLS WL LIMIT AMOUNTS.
AFTER THE DEPARTURE OF THE DEEP LYR FORCING...THE MOST PERSISTENT
SCATTERED SHOWERS WILL LINGER OVER THE NCENTRAL UNDER AXIS OF
SOMEWHAT DEEPER MSTR/LOWER HGTS FORECAST BY ALL THE GUIDANCE.
PTYPE IS TRICKY. WHILE HIER SFC DEWPT DEPRESSIONS/LOWER WBZ HGT
FAVOR MAINLY SN...LIGHTER PCPN INTENSITY WL LIMIT THE IMPACT OF
EVAPORATIVE COOLING. EXCEPT OVER THE HIER TERRAIN OF THE NCENTRAL...
SUSPECT ANY PCPN THAT FALLS WL BE MAINLY RA THIS AFTN WITH SOME
DAYTIME HEATING. BUT LINGERING PCPN SHOULD TURN PRIMARILY TO SN
AFTER SUNSET. GIVEN THE DISCONNECT BTWN DYNAMIC FORCING/MSTR/
NOCTURNAL COOLING...SUSPECT ANY SN ACCUMS WL BE UNDER AN INCH AT
MOST PLACES...PERHAPS UP TO 2 INCHES ON GRASSY SFCS OVER THE HIER
TERRAIN OF THE NCNTRL. LINGERING CLD COVER THRU THE NGT SHOULD LIMIT
NOCTURNAL FALL OF TEMP DESPITE RATHER CHILLY AIRMASS WITH H85 TEMPS
FCST ARND -5C AT 12Z FRI.
FRI...UPR MI IS FCST TO REMAIN UNDER AXIS OF LOWER HGTS/MID LVL
MSTR/SLOWLY WEAKENING CYC FLOW ON SRN FLANK OF UPR LO SLOWLY
DEPARTING TO THE N FM CENTRAL LK SUP INTO ONTARIO. BUT ANY PCPN
SHOULD BE NOTHING MORE THAN ISOLD-SCT SHOWERS IN THE ABSENCE OF DEEP
LYR QVECTOR CNVGC. SUSPECT THESE SHOWERS WL SHIFT TO PRIMARILY OVER
THE INLAND AREAS DURING THE AFTN WITH DAYTIME HEATING FORCING
DESTABILIZATION THERE AWAY FM THE COOLING/STABILIZING INFLUENCE OF
THE LKS. WHILE ANY PCPN MAY BE MAINLY SN IN THE MRNG...THIS DAYTIME
HEATING THAT LIFTS TEMPS INTO THE 40S AWAY FM LK COOLING SHOULD CHG
ANY PCPN TO RA IN THE AFTN.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 429 PM EDT THU MAY 15 2014
THE PESKY 500MB LOW STRETCHED FROM N ONTARIO THROUGH UPPER MI AT
FRIDAY NIGHT WILL KEEP COOL AIR SITUATED OVER THE AREA. 850MB TEMPS
WILL STILL BE A COOL -2 TO -6C. FCST MODELS CONTINUE TO INDICATE THE
POTENTIAL FOR INLAND CENTRAL AND E AREAS SEEING SOME LIGHT PRECIP
FROM MID MORNING ON SATURDAY WITH THE LIGHT W FLOW AT THE SFC AS THE
TROUGH EXITS OVER E UPPER MI. EITHER WAY...HIGHS SATURDAY WILL BE
APPROX 10F WARMER THAN WHAT WE HAVE BEEN EXPERIENCING OVER THE PAST
COUPLE OF DAYS. GIVEN NEAR SFC TEMPS
KEPT PRECIP OUT OF THE FCST FOR SUNDAY AS THE NEXT WEAK WAVE SWINGS
IN ON THE NW FLOW ALOFT. HOWEVER...ANYTHING THAT DOES COME ABOUT
SHOULD BE VERY LIGHT. KEPT WITH ONLY A PARTLY CLOUDY TO MOSTLY CLEAR
SKY ACROSS UPPER MI DURING THE DAY. IF CLOUDS REMAIN MINIMAL EXPECT
HIGH TEMPS TO RETURN TO NEAR NORMAL VALUES.
EXPECT BETTER WAA FOR THE START OF THE WORK WEEK...IN ADVANCE OF THE
SFC LOW SET UP OVER THE W DAKOTAS AND E MT AT 12Z MONDAY. THE
ELONGATED SFC RIDGE OVER THE E HALF OF UPPER MI WILL SHIFT E INTO
QUEBEC AND THE LOWER GREAT LAKES MONDAY THROUGH TUESDAY...WITH 850MB
TEMPS RISING BACK TO NEAR 10C BY 00Z WEDNESDAY. HAVE RAIN SHOWERS
BEING SLOWLY INTRODUCED W TO E LATE MONDAY THROUGH TUESDAY. THERE
DOESN/T LOOK TO BE A LOT OF INTERACTION BETWEEN THE MAIN
SHORTWAVE/TROUGH SKIMMING N MN AT 00Z WEDNESDAY AND THE S
DISTURBANCE OVER IA /AT LEAST OFF THE 12Z ECMWF/. THERE ARE ENOUGH
DISCREPANCIES IN THE MODELS BEYOND 12Z TUESDAY TO JUST GO WITH A
GENERAL MODEL BLEND AT THAT POINT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 653 PM EDT THU MAY 15 2014
SOME LIGHT SNOW WILL FALL AT CMX THROUGH THE TAF PERIOD...WITH VFR
CONDITIONS EXPECTED TO CONTINUE. THERE COULD BE VERY BRIEF MVFR
CONDITIONS THIS EVENING THERE. DRY LLVL AIR WL DOMINATE IWD THIS
FCST PERIOD AND THEY WILL STAY VFR. SOME -SN WL FALL THIS EVNG AT
SAW...WHICH WL BE CLOSER TO THE TRACK OF THE SFC LO. WITH A FVRBL
UPSLOPE N WIND... EXPECT MVFR WX TO PREDOMINATE AT THIS SITE
TNGT...BUT IFR CONDITIONS WILL BE IN FOR THIS EVENING IN A HEAVIER
SNOW BAND THAT IS AFFECTING THE SITE. CONDITIONS WL IMPROVE ON FRI
WITH DEPARTURE OF LOW AND DAYTIME HEATING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT
431 PM EDT THU MAY 15 2014
WINDS LESS THAN 30KTS WILL BE THE RULE THROUGH THE PERIOD. LAKE
SUPERIOR WILL BE STUCK BETWEEN A RIDGE ACROSS MIN AND A LOW OVER NE
LAKE HURON. A TROUGH WILL LINGER ACROSS LAKE SUPERIOR THROUGH FRIDAY
MORNING WHILE THE RIDGE DISSIPATES OVER THE CENTRAL AND NORTHERN
PLAINS. THE MAIN LOW WILL PUSH UP INTO S HUDSON BAY BY
SATURDAY...WHILE A RIDGE SHIFTS FROM CENTRAL CANADA ACROSS THE W
GREAT LAKES AND TO THE OH VALLEY. THE RIDGE WILL REMAIN NEARLY
STATIONARY INTO MONDAY AS IT LINKS UP WITH ANOTHER AREA OF HIGH
PRESSURE BUILDING S OUT OF HUDSON BAY...BEFORE SLOWLY SHIFTING EAST.
EXPECT A LOW OVER THE W DAKOTAS MONDAY MORNING WILL PUSH ACROSS MN
ON TUESDAY.
&&
.HYDROLOGY...
ISSUED AT 1128 AM EDT THU MAY 15 2014
THERE ARE NO FCST POINTS ON AREA RIVERS IN FLOOD. ADVISORIES REMAIN
AT THE STURGEON RIVER AT CHASSELL AS WELL AS WITCH LAKE AND CRYSTAL
FALLS ON THE MICHIGAMME. THE STEADY TO SLOW DOWNWARD TREND TO RIVER
LEVELS WILL CONTINUE THANKS TO LITTLE TO NO ADDITIONAL RUNOFF AND
COOL TEMPERATURES. STILL...THOSE LIVING NEAR RIVERS...CREEKS...AND
STREAMS SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...07
MARINE...ROLFSON
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
432 PM EDT THU MAY 15 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 332 PM EDT THU MAY 15 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
ACRS THE UPR MIDWEST...WITH 00Z-12Z H3 FALLS UP TO 180M...BTWN HI
AMPLITUDE RDG OVER THE W AND ALONG THE E COAST. THERE ARE TWO
SHRTWVS OF SIGNIFICANCE WITHIN THIS TROF. THE FIRST IS LIFTING NNEWD
THRU ERN WI TOWARD CENTRAL UPR MI AND THE SECOND IS DIGGING SEWD
THRU IOWA. DESPITE THE IMPRESSIVE SHARPENING OF THE UPR TROF...WRN
EDGE OF THE DEEPER WARM CONVEYOR BELT MSTR OVER FAR ERN UPR MI HAS
BEEN PUSHING SLOWLY TO THE E AND AWAY FM THE CWA. IN FACT...STLT
IMAGERY SHOWS IMPRESSIVE DRY SLOTTING UP THE LENGTH OF LK MI UNDER
JET SURGE REGION OF SHRTWV NOW LIFTING INTO CENTRAL UPR MI.
THERE IS ANOTHER AREA OF ENHANCED...COLDER CLD TOPS OVER ECENTRAL WI
ON CYC SIDE OF THIS SHRTWV/ASSOCIATED H7 LO AND TO THE E OF THE
OTHER SHRTWV IN IOWA. DESPITE A FAIRLY MOIST LYR BTWN H9-5 SHOWN ON
THE 12Z GRB RAOB...RA UNDER THIS AREA OF ENHANCED CLD HAS BEEN LGT
AND SOMEWHAT SPOTTY. THE PROBLEM APPEARS TO BE DRY LLVL AIR SHOWN ON
THE 12Z MPX/INL RAOBS. SFC DEWPT DEPRESSIONS OVER THE W HALF OF UPR
MI ROSE AS HI AS 15-20F. THE FEED OF THIS LLVL DRY AIR LIMITED THE
EXPANSION OF PCPN TO THE W DESPITE RATHER IMPRESSIVE DEEP LYR QVECTOR
CNVGC ASSOCIATED WITH SHRTWV LIFTING INTO CENTRAL UPR MI.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS/PTYPE ASSOCIATED WITH
PAIR OF SHRTWVS NOTED ABOVE. LACK OF CLEAR PHASING BTWN THESE TWO
SEPARATE DISTURBANCES/AREAS OF DEEPER MSTR/IMPACT OF LLVL DRY AIR
APPEARS TO BE THE CHIEF LIMITING FACTOR ON PRECIP INTENSITY/
COVERAGE.
LATE THIS AFTN/TNGT...GIVEN THE UPR DRY SLOTTING BTWN WARM CONVEYOR
BELT MSTR/SOMEWHAT SHALLOWER MSTR SHOWN ON THE 12Z GRB RAOB AS WELL
AS THE LLVL DRY AIR IN PLACE OVER THE W HALF OF THE CWA/LATEST OBS
WV TRENDS TO THE S...PREFER THE DRIER LOOK OF THE 12Z LOCAL WRF-ARW
MODEL FOR POPS/QPF. THERE WL BE SOME EXPANSION OF THE PRECIP AREA
INTO THIS EVNG OVER THE CENTRAL AND E WITH PASSAGE OF H7 LO OVER
NEWBERRY AND ASSOCIATED BAND OF F85-7 FGEN JUST TO THE W UNDER AREA
OF DEEP LYR QVECTOR CNVGC. BUT PASSAGE OF AREA OF DEEP LYR QVECTOR
CNVGC TO THE N BY 03Z WL DIMINISH ANY HEAVIER MIXED PCPN. UPSLOPE N
WIND WL BRING MORE NMRS SHOWERS TO THE NCENTRAL...ESPECIALLY THE
HIER TERRAIN...BUT OVERALL DRYNESS OF THE LLVLS WL LIMIT AMOUNTS.
AFTER THE DEPARTURE OF THE DEEP LYR FORCING...THE MOST PERSISTENT
SCATTERED SHOWERS WILL LINGER OVER THE NCENTRAL UNDER AXIS OF
SOMEWHAT DEEPER MSTR/LOWER HGTS FORECAST BY ALL THE GUIDANCE.
PTYPE IS TRICKY. WHILE HIER SFC DEWPT DEPRESSIONS/LOWER WBZ HGT
FAVOR MAINLY SN...LIGHTER PCPN INTENSITY WL LIMIT THE IMPACT OF
EVAPORATIVE COOLING. EXCEPT OVER THE HIER TERRAIN OF THE NCENTRAL...
SUSPECT ANY PCPN THAT FALLS WL BE MAINLY RA THIS AFTN WITH SOME
DAYTIME HEATING. BUT LINGERING PCPN SHOULD TURN PRIMARILY TO SN
AFTER SUNSET. GIVEN THE DISCONNECT BTWN DYNAMIC FORCING/MSTR/
NOCTURNAL COOLING...SUSPECT ANY SN ACCUMS WL BE UNDER AN INCH AT
MOST PLACES...PERHAPS UP TO 2 INCHES ON GRASSY SFCS OVER THE HIER
TERRAIN OF THE NCNTRL. LINGERING CLD COVER THRU THE NGT SHOULD LIMIT
NOCTURNAL FALL OF TEMP DESPITE RATHER CHILLY AIRMASS WITH H85 TEMPS
FCST ARND -5C AT 12Z FRI.
FRI...UPR MI IS FCST TO REMAIN UNDER AXIS OF LOWER HGTS/MID LVL
MSTR/SLOWLY WEAKENING CYC FLOW ON SRN FLANK OF UPR LO SLOWLY
DEPARTING TO THE N FM CENTRAL LK SUP INTO ONTARIO. BUT ANY PCPN
SHOULD BE NOTHING MORE THAN ISOLD-SCT SHOWERS IN THE ABSENCE OF DEEP
LYR QVECTOR CNVGC. SUSPECT THESE SHOWERS WL SHIFT TO PRIMARILY OVER
THE INLAND AREAS DURING THE AFTN WITH DAYTIME HEATING FORCING
DESTABILIZATION THERE AWAY FM THE COOLING/STABILIZING INFLUENCE OF
THE LKS. WHILE ANY PCPN MAY BE MAINLY SN IN THE MRNG...THIS DAYTIME
HEATING THAT LIFTS TEMPS INTO THE 40S AWAY FM LK COOLING SHOULD CHG
ANY PCPN TO RA IN THE AFTN.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 429 PM EDT THU MAY 15 2014
THE PESKY 500MB LOW STRETCHED FROM N ONTARIO THROUGH UPPER MI AT
FRIDAY NIGHT WILL KEEP COOL AIR SITUATED OVER THE AREA. 850MB TEMPS
WILL STILL BE A COOL -2 TO -6C. FCST MODELS CONTINUE TO INDICATE THE
POTENTIAL FOR INLAND CENTRAL AND E AREAS SEEING SOME LIGHT PRECIP
FROM MID MORNING ON SATURDAY WITH THE LIGHT W FLOW AT THE SFC AS THE
TROUGH EXITS OVER E UPPER MI. EITHER WAY...HIGHS SATURDAY WILL BE
APPROX 10F WARMER THAN WHAT WE HAVE BEEN EXPERIENCING OVER THE PAST
COUPLE OF DAYS. GIVEN NEAR SFC TEMPS
KEPT PRECIP OUT OF THE FCST FOR SUNDAY AS THE NEXT WEAK WAVE SWINGS
IN ON THE NW FLOW ALOFT. HOWEVER...ANYTHING THAT DOES COME ABOUT
SHOULD BE VERY LIGHT. KEPT WITH ONLY A PARTLY CLOUDY TO MOSTLY CLEAR
SKY ACROSS UPPER MI DURING THE DAY. IF CLOUDS REMAIN MINIMAL EXPECT
HIGH TEMPS TO RETURN TO NEAR NORMAL VALUES.
EXPECT BETTER WAA FOR THE START OF THE WORK WEEK...IN ADVANCE OF THE
SFC LOW SET UP OVER THE W DAKOTAS AND E MT AT 12Z MONDAY. THE
ELONGATED SFC RIDGE OVER THE E HALF OF UPPER MI WILL SHIFT E INTO
QUEBEC AND THE LOWER GREAT LAKES MONDAY THROUGH TUESDAY...WITH 850MB
TEMPS RISING BACK TO NEAR 10C BY 00Z WEDNESDAY. HAVE RAIN SHOWERS
BEING SLOWLY INTRODUCED W TO E LATE MONDAY THROUGH TUESDAY. THERE
DOESN/T LOOK TO BE A LOT OF INTERACTION BETWEEN THE MAIN
SHORTWAVE/TROUGH SKIMMING N MN AT 00Z WEDNESDAY AND THE S
DISTURBANCE OVER IA /AT LEAST OFF THE 12Z ECMWF/. THERE ARE ENOUGH
DISCREPANCIES IN THE MODELS BEYOND 12Z TUESDAY TO JUST GO WITH A
GENERAL MODEL BLEND AT THAT POINT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 121 PM EDT THU MAY 15 2014
GUSTY N WINDS THIS AFTN UNDER TIGHTER PRES GRADIENT ON THE WRN FLANK
OF LO PRES MOVING THRU THE CENTRAL LKS WL DIMINISH TNGT WITH THE
CLOSER APRCH OF HI PRES/WEAKER GRADIENT AND LOSS OF DAYTIME HEATING/
MIXING. OTRW...ALTHOUGH SOME FLURRIES MAY FALL AT CMX...VFR
CONDITIONS ASSOCIATED WITH DRY LLVL AIR WL DOMINATE CMX AND IWD THIS
FCST PERIOD. SOME -SN WL FALL THIS AFTN/EVNG AT SAW...WHICH WL BE
CLOSER TO THE TRACK OF THE SFC LO. WITH A FVRBL UPSLOPE N WIND...
EXPECT MVFR WX TO PREDOMINATE AT THIS SITE TNGT. CONDITIONS WL
IMPROVE ON FRI WITH DEPARTURE OF LO/DAYTIME HEATING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT
431 PM EDT THU MAY 15 2014
WINDS LESS THAN 30KTS WILL BE THE RULE THROUGH THE PERIOD. LAKE
SUPERIOR WILL BE STUCK BETWEEN A RIDGE ACROSS MIN AND A LOW OVER NE
LAKE HURON. A TROUGH WILL LINGER ACROSS LAKE SUPERIOR THROUGH FRIDAY
MORNING WHILE THE RIDGE DISSIPATES OVER THE CENTRAL AND NORTHERN
PLAINS. THE MAIN LOW WILL PUSH UP INTO S HUDSON BAY BY
SATURDAY...WHILE A RIDGE SHIFTS FROM CENTRAL CANADA ACROSS THE W
GREAT LAKES AND TO THE OH VALLEY. THE RIDGE WILL REMAIN NEARLY
STATIONARY INTO MONDAY AS IT LINKS UP WITH ANOTHER AREA OF HIGH
PRESSURE BUILDING S OUT OF HUDSON BAY...BEFORE SLOWLY SHIFTING EAST.
EXPECT A LOW OVER THE W DAKOTAS MONDAY MORNING WILL PUSH ACROSS MN
ON TUESDAY.
&&
.HYDROLOGY...
ISSUED AT 1128 AM EDT THU MAY 15 2014
THERE ARE NO FCST POINTS ON AREA RIVERS IN FLOOD. ADVISORIES REMAIN
AT THE STURGEON RIVER AT CHASSELL AS WELL AS WITCH LAKE AND CRYSTAL
FALLS ON THE MICHIGAMME. THE STEADY TO SLOW DOWNWARD TREND TO RIVER
LEVELS WILL CONTINUE THANKS TO LITTLE TO NO ADDITIONAL RUNOFF AND
COOL TEMPERATURES. STILL...THOSE LIVING NEAR RIVERS...CREEKS...AND
STREAMS SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...ROLFSON
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
333 PM EDT THU MAY 15 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 332 PM EDT THU MAY 15 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEPENING UPR TROF
ACRS THE UPR MIDWEST...WITH 00Z-12Z H3 FALLS UP TO 180M...BTWN HI
AMPLITUDE RDG OVER THE W AND ALONG THE E COAST. THERE ARE TWO
SHRTWVS OF SIGNIFICANCE WITHIN THIS TROF. THE FIRST IS LIFTING NNEWD
THRU ERN WI TOWARD CENTRAL UPR MI AND THE SECOND IS DIGGING SEWD
THRU IOWA. DESPITE THE IMPRESSIVE SHARPENING OF THE UPR TROF...WRN
EDGE OF THE DEEPER WARM CONVEYOR BELT MSTR OVER FAR ERN UPR MI HAS
BEEN PUSHING SLOWLY TO THE E AND AWAY FM THE CWA. IN FACT...STLT
IMAGERY SHOWS IMPRESSIVE DRY SLOTTING UP THE LENGTH OF LK MI UNDER
JET SURGE REGION OF SHRTWV NOW LIFTING INTO CENTRAL UPR MI.
THERE IS ANOTHER AREA OF ENHANCED...COLDER CLD TOPS OVER ECENTRAL WI
ON CYC SIDE OF THIS SHRTWV/ASSOCIATED H7 LO AND TO THE E OF THE
OTHER SHRTWV IN IOWA. DESPITE A FAIRLY MOIST LYR BTWN H9-5 SHOWN ON
THE 12Z GRB RAOB...RA UNDER THIS AREA OF ENHANCED CLD HAS BEEN LGT
AND SOMEWHAT SPOTTY. THE PROBLEM APPEARS TO BE DRY LLVL AIR SHOWN ON
THE 12Z MPX/INL RAOBS. SFC DEWPT DEPRESSIONS OVER THE W HALF OF UPR
MI ROSE AS HI AS 15-20F. THE FEED OF THIS LLVL DRY AIR LIMITED THE
EXPANSION OF PCPN TO THE W DESPITE RATHER IMPRESSIVE DEEP LYR QVECTOR
CNVGC ASSOCIATED WITH SHRTWV LIFTING INTO CENTRAL UPR MI.
MAIN FCST CONCERNS IN THE SHORT TERM ARE POPS/PTYPE ASSOCIATED WITH
PAIR OF SHRTWVS NOTED ABOVE. LACK OF CLEAR PHASING BTWN THESE TWO
SEPARATE DISTURBANCES/AREAS OF DEEPER MSTR/IMPACT OF LLVL DRY AIR
APPEARS TO BE THE CHIEF LIMITING FACTOR ON PRECIP INTENSITY/
COVERAGE.
LATE THIS AFTN/TNGT...GIVEN THE UPR DRY SLOTTING BTWN WARM CONVEYOR
BELT MSTR/SOMEWHAT SHALLOWER MSTR SHOWN ON THE 12Z GRB RAOB AS WELL
AS THE LLVL DRY AIR IN PLACE OVER THE W HALF OF THE CWA/LATEST OBS
WV TRENDS TO THE S...PREFER THE DRIER LOOK OF THE 12Z LOCAL WRF-ARW
MODEL FOR POPS/QPF. THERE WL BE SOME EXPANSION OF THE PRECIP AREA
INTO THIS EVNG OVER THE CENTRAL AND E WITH PASSAGE OF H7 LO OVER
NEWBERRY AND ASSOCIATED BAND OF F85-7 FGEN JUST TO THE W UNDER AREA
OF DEEP LYR QVECTOR CNVGC. BUT PASSAGE OF AREA OF DEEP LYR QVECTOR
CNVGC TO THE N BY 03Z WL DIMINISH ANY HEAVIER MIXED PCPN. UPSLOPE N
WIND WL BRING MORE NMRS SHOWERS TO THE NCENTRAL...ESPECIALLY THE
HIER TERRAIN...BUT OVERALL DRYNESS OF THE LLVLS WL LIMIT AMOUNTS.
AFTER THE DEPARTURE OF THE DEEP LYR FORCING...THE MOST PERSISTENT
SCATTERED SHOWERS WILL LINGER OVER THE NCENTRAL UNDER AXIS OF
SOMEWHAT DEEPER MSTR/LOWER HGTS FORECAST BY ALL THE GUIDANCE.
PTYPE IS TRICKY. WHILE HIER SFC DEWPT DEPRESSIONS/LOWER WBZ HGT
FAVOR MAINLY SN...LIGHTER PCPN INTENSITY WL LIMIT THE IMPACT OF
EVAPORATIVE COOLING. EXCEPT OVER THE HIER TERRAIN OF THE NCENTRAL...
SUSPECT ANY PCPN THAT FALLS WL BE MAINLY RA THIS AFTN WITH SOME
DAYTIME HEATING. BUT LINGERING PCPN SHOULD TURN PRIMARILY TO SN
AFTER SUNSET. GIVEN THE DISCONNECT BTWN DYNAMIC FORCING/MSTR/
NOCTURNAL COOLING...SUSPECT ANY SN ACCUMS WL BE UNDER AN INCH AT
MOST PLACES...PERHAPS UP TO 2 INCHES ON GRASSY SFCS OVER THE HIER
TERRAIN OF THE NCNTRL. LINGERING CLD COVER THRU THE NGT SHOULD LIMIT
NOCTURNAL FALL OF TEMP DESPITE RATHER CHILLY AIRMASS WITH H85 TEMPS
FCST ARND -5C AT 12Z FRI.
FRI...UPR MI IS FCST TO REMAIN UNDER AXIS OF LOWER HGTS/MID LVL
MSTR/SLOWLY WEAKENING CYC FLOW ON SRN FLANK OF UPR LO SLOWLY
DEPARTING TO THE N FM CENTRAL LK SUP INTO ONTARIO. BUT ANY PCPN
SHOULD BE NOTHING MORE THAN ISOLD-SCT SHOWERS IN THE ABSENCE OF DEEP
LYR QVECTOR CNVGC. SUSPECT THESE SHOWERS WL SHIFT TO PRIMARILY OVER
THE INLAND AREAS DURING THE AFTN WITH DAYTIME HEATING FORCING
DESTABILIZATION THERE AWAY FM THE COOLING/STABILIZING INFLUENCE OF
THE LKS. WHILE ANY PCPN MAY BE MAINLY SN IN THE MRNG...THIS DAYTIME
HEATING THAT LIFTS TEMPS INTO THE 40S AWAY FM LK COOLING SHOULD CHG
ANY PCPN TO RA IN THE AFTN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 531 AM EDT THU MAY 15 2014
ANOMALOUSLY DEEP TROF (500MB HEIGHT ANOMALIES PEAKING AROUND 3
STANDARD DEVIATIONS OVER THE LOWER MISSISSIPPI VALLEY) WITH AXIS
ALONG THE MISSISSIPPI RIVER TO START THE PERIOD WILL LIFT NE AND
WEAKEN OVER THE NEXT SEVERAL DAYS. EARLY NEXT WEEK...THE WEAKENED
TROF WILL EXTEND FROM HUDSON BAY TO NEW ENGLAND WHILE A MID/UPPER
LEVEL RIDGE BUILDS INTO THE WRN GREAT LAKES. RIDGE LOOKS TO REMAIN
IN PLACE FOR PERHAPS A FEW DAYS BEFORE IT IS SUPPRESSED BY ENERGY
ROUNDING RIDGE AND THEN HEADING INTO THE LINGERING NE TROF. AS A
RESULT OF THIS PATTERN EVOLUTION...UNSEASONABLY COLD AIR TO START
THE LONG TERM WILL MODERATE TOWARD NEAR NORMAL MID TO LATE MAY
CONDITIONS EARLY NEXT WEEK. LOOKING OUT FARTHER AHEAD...THERE ARE
STILL NO INDICATIONS OF SUSTAINED ABOVE NORMAL TEMPS SETTING UP IN
THE NEXT WEEK TO 14 DAYS. AFTER PCPN ASSOCIATED WITH THE DEEP TROF
EXITS THIS WEEKEND...SOME DRY DAYS SHOULD SET UP FOR EARLY NEXT
WEEK. HOW LONG THE DRY WEATHER LINGERS WILL DEPEND ON HOW
AGGRESSIVELY SHORTWAVES AND ASSOCIATED PCPN ENCROACH ON DRY AIR MASS
OVER THE GREAT LAKES ASSOCIATED WITH SFC HIGH PRES RIDGE EXTENDING S
FROM HUDSON BAY. IT MAY BE A CASE WHERE SHRA REACH WRN UPPER
MI...BUT THE E STAYS DRY.
BEGINNING FRI...DEEP MOISTURE AND CYCLONIC FLOW SHOULD SUPPORT LIGHT
PCPN (MOSTLY SNOW BASED ON FCST SOUNDINGS) IN THE MORNING...MAINLY
FROM THE KEWEENAW INTO NCNTRL UPPER MI WHERE CYCLONIC UPSLOPE NNW
LOW-LEVEL FLOW WILL AID THE PCPN. HOWEVER...WITH DEEP LAYER QVECTOR
DIVERGENCE SHOWN SWINGING N ACROSS THE AREA IN THE WAKE OF SHORTWAVE
LIFTING N THRU ERN UPPER MI TONIGHT WHICH ALSO LEADS TO BEST DEEP
MOISTURE ALSO SHIFTING N...PCPN WILL BE DIMINISHING...ESPECIALLY
AWAY FROM THE UPSLOPE FAVORED LOCATIONS. BY AFTN...PCPN WILL TURN TO
SCT SHOWERY AS STEADIER SYNOPTIC PCPN EXITS AND MID MAY DAYTIME
HEATING THRU CLOUD COVER GENERATES SOME INSTABILITY. DAYTIME HEATING
WILL ALSO WORK TO CHANGE PTYPE TO AT LEAST A MIX OF RAIN/SNOW. THERE
MAY BE SOME LIGHT ADDITIONAL SNOW ACCUM (UNDER AN INCH) OVER THE
HIGHER TERRAIN OF THE NCNTRL IN THE MORNING...BUT NO ADDITIONAL SNOW
ACCUM WILL OCCUR IN THE AFTN. IT WILL BE UNSEASONABLY COLD WITH
TEMPS NOT REACHING 40F IN SOME AREAS NEAR LAKE SUPERIOR...AND
STRUGGLING TO REACH 50F FAR SCNTRL.
FRI NIGHT...COVERAGE OF LINGERING -SHRA/-SHSN WILL DIMINISH AS THE
CLOSED LOW LIFTS SLOWLY TO THE N IN ONTARIO AND CYCLONIC FLOW
WEAKENS.
ON SAT...MID/UPPER LEVEL TROF AXIS WILL CONTINUE TO EXTEND S THRU
THE UPPER LAKES. UNDER TROF...COLD POOL ALOFT AND MID MAY INSOLATION
WILL CONSPIRE TO INCREASE COVERAGE OF SCT SHRA. THE SHOWERS SHOULD
BECOME CONFINED TO MAINLY THE INTERIOR DURING THE DAY WITH DAYTIME
HEATING PROMOTING DESTABILIZATION OVER THE LAND WHILE AREAS NEAR THE
LAKES COME UNDER THE INFLUENCE OF THE STABILIZING MARINE LAYER
BEHIND INLAND PUSHING LAKE BREEZES. BEST CHC OF SHRA WILL BE IN THE
INTERIOR CNTRL. WITH 850MB TEMPS AROUND -4C AT 12Z SAT...PCPN SHOULD
BE MIXED WITH SNOW IN THE MORNING. DAYTIME HEATING WILL THEN CAUSE
THE PTYPE TO BECOME ONLY LIQUID IN THE AFTN...BUT THERE COULD BE
SOME GRAUPEL OR SNOW IN THE AFTN IF MORE VIGOROUS CONVECTION
DEVELOPS.
SAT NIGHT INTO MON...AS UPPER TROF OVER THE GREAT LAKES LIFTS TO THE
NE AND WEAKENS...UPPER RIDGE AND SFC HIGH PRES ARE FCST TO BUILD
OVER THE AREA...BRINGING A PERIOD OF DRY WX. HOWEVER...IT IS NOTED
THAT MEDIUM RANGE GUIDANCE SHOWS A SHORTWAVE TRACKING SE THRU NRN
ONTARIO INTO THE DEPARTING TROF. ECMWF IS STRONGEST WITH FEATURE AND
HAS MORE WIDESPREAD SHRA DEVELOPING ALONG ASSOCIATED COLD FRONT
DROPPING S TOWARD LAKE SUPERIOR. AT THIS POINT...EXPECT STABLE AIR
OVER CHILLY LAKE SUPERIOR TO PREVENT ANY OF THESE SFC BASED -SHRA
FROM REACHING UPPER MI. WITH SOME SUNSHINE...FCST 850MB TEMPS AROUND
2C ON SUN AND 5C ON MON SHOULD ALLOW AFTN TEMPS TO REACH AROUND 60F
AND INTO THE 60S RESPECTIVELY AWAY FROM THE COOLING INFLUENCE OF THE
LAKES. EARLY SUN AND MON MORNING WILL BE CHILLY WITH LIGHT WINDS
NEAR THE SFC RIDGE AXIS ALLOWING TEMPS TO DIP INTO THE 30S AND
POSSIBLY EVEN THE 20S AT SOME OF THE TRADITIONAL INTERIOR COLD
SPOTS.
MON NIGHT THRU WED...MEDIUM RANGE MODELS SHOW SHORTWAVE RIDING OVER
MID/UPPER RIDGE CENTERED IN THE MISSISSIPPI RIVER VALLEY. TIMING OF
FEATURE AND HOW QUICKLY PCPN SPREADS INTO DRY AIR MASS EMANATING
FROM HIGH PRES RIDGE EXTENDING S FROM HUDSON BAY STILL NEED TO BE
WORKED OUT. FOR NOW...WILL CARRY MODEL CONSENSUS CHC POPS GRADUALLY
SPREADING E TO REFLECT THE PCPN POTENTIAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 121 PM EDT THU MAY 15 2014
GUSTY N WINDS THIS AFTN UNDER TIGHTER PRES GRADIENT ON THE WRN FLANK
OF LO PRES MOVING THRU THE CENTRAL LKS WL DIMINISH TNGT WITH THE
CLOSER APRCH OF HI PRES/WEAKER GRADIENT AND LOSS OF DAYTIME HEATING/
MIXING. OTRW...ALTHOUGH SOME FLURRIES MAY FALL AT CMX...VFR
CONDITIONS ASSOCIATED WITH DRY LLVL AIR WL DOMINATE CMX AND IWD THIS
FCST PERIOD. SOME -SN WL FALL THIS AFTN/EVNG AT SAW...WHICH WL BE
CLOSER TO THE TRACK OF THE SFC LO. WITH A FVRBL UPSLOPE N WIND...
EXPECT MVFR WX TO PREDOMINATE AT THIS SITE TNGT. CONDITIONS WL
IMPROVE ON FRI WITH DEPARTURE OF LO/DAYTIME HEATING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 AM EDT THU MAY 15 2014
LOW PRES WILL LIFT FROM NE INDIANA ACROSS LAKE HURON TODAY AND THEN
TO NEAR JAMES BAY BY FRI EVENING. AS A RESULT...EXPECT WINDS TO
INCREASE TO 20-25KT OVER THE E HALF OF LAKE SUPERIOR TODAY/TONIGHT.
WINDS WILL BE LIGHTER OVER THE W. WINDS WILL DIMINISH FRIDAY AS THE
LOW MOVES FARTHER AWAY. FRI NIGHT THRU THE WEEKEND...WINDS WILL BE
UNDER 20KT AND EVEN UNDER 10KT AT TIMES UNDER WEAKER PRES GRADIENT.
LOW PRES DEVELOPING OVER THE PLAINS EARLY NEXT WEEK WILL BRING SOME
INCREASE IN E TO SE WINDS. AS IS NORMALLY THE CASE IN THIS TYPE OF
PATTERN...WILL NEED TO WATCH FOR STRONGER WINDS TO DEVELOP OVER THE
WRN PART OF THE LAKE DUE TO COASTAL CONVERGENCE/FUNNELING.
&&
.HYDROLOGY...
ISSUED AT 1128 AM EDT THU MAY 15 2014
THERE ARE NO FCST POINTS ON AREA RIVERS IN FLOOD. ADVISORIES REMAIN
AT THE STURGEON RIVER AT CHASSELL AS WELL AS WITCH LAKE AND CRYSTAL
FALLS ON THE MICHIGAMME. THE STEADY TO SLOW DOWNWARD TREND TO RIVER
LEVELS WILL CONTINUE THANKS TO LITTLE TO NO ADDITIONAL RUNOFF AND
COOL TEMPERATURES. STILL...THOSE LIVING NEAR RIVERS...CREEKS...AND
STREAMS SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...KC
MARINE...ROLFSON
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
123 PM EDT THU MAY 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 531 AM EDT THU MAY 15 2014
WV LOOP AND ANALYSIS OF RAP H5 HEIGHTS INDICATE DEEP TROUGH FROM
PARENT UPPER LOW OVER EASTERN HUDSON BAY TO ONE SIGNIFICANT TROUGH
DROPPING SE OVER THE NORTHERN PLAINS/MINNESOTA AND ANOTHER LIFTING
NORTHEAST OVER ILLINOIS. PLUME OF DEEP MOISTURE WITH ORIGIN IN THE
EQUATORIAL EAST PACIFIC SURGING NORTH AHEAD OF UPPER TROUGH AND SFC
TROUGH IS SUPPORTING LARGE AREA OF SHOWERS AND SOME TSRA FM SE CONUS
TO CENTRAL GREAT LAKES. THUS FAR PRECIPITATION IS AS CLOSE AS EAST
CENTRAL WI AND FAR EASTERN UPR MICHIGAN. BAND OF RAIN IS ALONG AND
EAST OF H7 FRONTOGENESIS JUST AHEAD OF SHORTWAVE TAKING AIM ON LK
MICHIGAN. 00Z GRB SOUNDING SHOWED DRY AIR BLO H6...AND THIS IS SO FAR
RESTRICTING WESTWARD EXPANSION OF PRECIPITATION. OVER THE MQT CWA
THERE IS A THICK SHIELD OF MID CLOUDS WHICH HAS MAINLY HELD TEMPS UP
IN THE MID 30S TO LOWER 40S. ONLY EXCEPTION IS INTERIOR WEST WHERE
TEMPS HAVE LOCALLY DIPPED INTO THE UPPER 20S.
FOR TODAY...SHORTWAVE OVER ILLINOIS LIFTS ALMOST DUE NORTH TOWARD
CNTRL UPR MICHIGAN BY EARLY AFTN WHILE ADDITIONAL SHORTWAVES DIG
INTO THE TROUGH FARTHER WEST OVER MINNESOTA/UPPER MISSISSIPPI
RIVER VALLEY. EXPECT PRECIP TO THE SE SUPPORTED BY THE FRONT AT H7
TO TRY TO BACK WESTWARD INTO AT LEAST SOUTH CENTRAL AND EASTERN CWA
THROUGH THE MORNING. BASED ON RAP SOUNDINGS AND CURRENT SFC T/TD
COULD SEE MIX OF RAIN/SNOW ONCE PRECIP BEGINS JUST ABOUT ANYWHERE IN
THE EASTERN CWA. PRECIP SHOULD THEN EXPAND FOR ROUGHLY THE EAST HALF
OF CWA EARLY TO MID AFTN AS THE SHORTWAVE/H85-H5 Q-VECTOR CONVERGENCE
AND SWATH OF HIGHER H7-H85 RH ALONG AND WEST OF H85-H7 LOWS...
SHOWING UP AS ENHANCED CLOUD ON WV LOOP OVER IA AND WI..LIFT ACROSS
THE AREA AND AS MAIN SFC LOW LIFTS TOWARD LAKE HURON. NORTH WINDS ON
EDGE OF SFC-H85 LOWS MAY ALLOW FOR EXPANSION OF PRECIP AS FAR WEST
AS NCNTRL UPR MICHIGAN. FORECAST SOUNDINGS INDICATE THAT AS PRECIP
WOULD BEGIN TEMPS WILL FALL INTO THE MID 30S AND SNOW WOULD BE THE
MAIN PTYPE. SNOW ACCUMS WILL BE HELD DOWN BY WARMER GROUND TEMPS AND
SINCE THIS IS OCCURRING DURING THE DAY...BUT WILL NOT BE SURPRISED
TO SEE AN INCH OF SLUSHY SNOW ON GRASSY SURFACES BY EVENING OVER
EAST AS STRONGER LIFT/DYNAMIC COOLING MAY OUTWEIGH THESE OTHER
FACTORS.
MOVING INTO TONIGHT...WIDESPREAD PRECIP...MAINLY IN THE FORM OF
SNOW...WILL BE ONGOING OVER NORTH CENTRAL INTO EAST HALF OF UPR
MICHIGAN AS SHORTWAVE/LARGER SCALE ASCENT IS LIFTING THROUGH.
BEGINNING TO THINK WEST EDGE OF WIDESPREAD PRECIP MAY BE PULLED
FARTHER WEST...PERHAPS TO CMX-LNL LINE AS INITIAL SHORTWAVE MAY
BE NUDGED WEST WITH THE ADDITIONAL INCOMING SHORTWAVE ENERGY ON THE
BACK SIDE OF THE TROUGH. DOES NOT LOOK LIKE COMPLETE PHASING BTWN
THESE FEATURES...BUT IT WILL AFFECT PRECIP PATTERN SOMEWHAT. THINK
THAT THE EVENING TIME FRAME IS WHEN BEST CHANCE FOR ACCUMULATING
SNOW WILL BE FOR NCNTRL UPR MICHIGAN...ESPECIALLY THE HIGHER
TERRAIN AREAS AS THE NORTH WINDS PROVIDE ADDITIONAL UPSLOPE LIFTING.
SOUNDINGS POINT TO SLR/S STRUGGLING TO 10:1 BUT MORE LARGE SCALE
LIFT WILL HELP THIS OUT SOME. CURRENT FORECAST USED BLEND OF GFS AND
ECMWF WITH A BIT OF 00Z NAM TO PICK UP ON THE HIGHER TERRAIN AREAS
BETTER. THIS RESULTED IN 1-2 INCHES OF SNOW TONIGHT. AS HAS BEEN
CONSTANT THEME WITH THIS SYSTEM...THINGS LOOK TO BE CHANGING AGAIN.
BASED ON CURRENT TRENDS IN ENHANCED CLOUDS AND POSSIBLE FARTHER WEST
TRACK OF SYSTEM...THINK THAT THE 06Z NAM RUN WHICH SHOWS ROUGHLY
DOUBLE OF THE TOTAL QPF IT DID ON THE 00Z RUN COULD BE ON THE RIGHT
TRACK. MAY BE OVERPLAYING THINGS SOME THOUGH. IF THIS IDEA IS MORE
IN LINE...THEN AREAS FROM KEWEENAW TO DELTA COUNTY WOULD SEE AROUND
1 INCH OF SNOW TONIGHT...WHILE HIGHER TERRAIN OF NCNTRL IN BARAGA
AND MARQUETTE COUNTIES COULD END UP WITH 2 TO 3 INCHES...MAYBE 4
INCHES.
NO ADVISORY WAS ISSUED ATTM...BUT DAYSHIFT CAN TAKE A LOOK AT LATEST
DATA AND MAKE A CALL IF ONE IS NEEDED. GREATEST CHANCE THAT THE SNOW
WOULD IMPACT ROADS WOULD NOT BE UNTIL LATER TONIGHT AS BLYR
SUFFICIENTLY COOLS...BUT THEN THE QUESTION IS WILL THE SNOWFALL
RATES BE ALL THAT HEAVY OVERNIGHT TONIGHT. GIVEN THE
UNCERTAINTY...EVEN THOUGH IT IS PRETTY MUCH HERE...WILL CONTINUE TO
MENTION IN THE HAZARDOUS WEATHER OUTLOOK AND EHWO GRAPHICS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 531 AM EDT THU MAY 15 2014
ANOMALOUSLY DEEP TROF (500MB HEIGHT ANOMALIES PEAKING AROUND 3
STANDARD DEVIATIONS OVER THE LOWER MISSISSIPPI VALLEY) WITH AXIS
ALONG THE MISSISSIPPI RIVER TO START THE PERIOD WILL LIFT NE AND
WEAKEN OVER THE NEXT SEVERAL DAYS. EARLY NEXT WEEK...THE WEAKENED
TROF WILL EXTEND FROM HUDSON BAY TO NEW ENGLAND WHILE A MID/UPPER
LEVEL RIDGE BUILDS INTO THE WRN GREAT LAKES. RIDGE LOOKS TO REMAIN
IN PLACE FOR PERHAPS A FEW DAYS BEFORE IT IS SUPPRESSED BY ENERGY
ROUNDING RIDGE AND THEN HEADING INTO THE LINGERING NE TROF. AS A
RESULT OF THIS PATTERN EVOLUTION...UNSEASONABLY COLD AIR TO START
THE LONG TERM WILL MODERATE TOWARD NEAR NORMAL MID TO LATE MAY
CONDITIONS EARLY NEXT WEEK. LOOKING OUT FARTHER AHEAD...THERE ARE
STILL NO INDICATIONS OF SUSTAINED ABOVE NORMAL TEMPS SETTING UP IN
THE NEXT WEEK TO 14 DAYS. AFTER PCPN ASSOCIATED WITH THE DEEP TROF
EXITS THIS WEEKEND...SOME DRY DAYS SHOULD SET UP FOR EARLY NEXT
WEEK. HOW LONG THE DRY WEATHER LINGERS WILL DEPEND ON HOW
AGGRESSIVELY SHORTWAVES AND ASSOCIATED PCPN ENCROACH ON DRY AIR MASS
OVER THE GREAT LAKES ASSOCIATED WITH SFC HIGH PRES RIDGE EXTENDING S
FROM HUDSON BAY. IT MAY BE A CASE WHERE SHRA REACH WRN UPPER
MI...BUT THE E STAYS DRY.
BEGINNING FRI...DEEP MOISTURE AND CYCLONIC FLOW SHOULD SUPPORT LIGHT
PCPN (MOSTLY SNOW BASED ON FCST SOUNDINGS) IN THE MORNING...MAINLY
FROM THE KEWEENAW INTO NCNTRL UPPER MI WHERE CYCLONIC UPSLOPE NNW
LOW-LEVEL FLOW WILL AID THE PCPN. HOWEVER...WITH DEEP LAYER QVECTOR
DIVERGENCE SHOWN SWINGING N ACROSS THE AREA IN THE WAKE OF SHORTWAVE
LIFTING N THRU ERN UPPER MI TONIGHT WHICH ALSO LEADS TO BEST DEEP
MOISTURE ALSO SHIFTING N...PCPN WILL BE DIMINISHING...ESPECIALLY
AWAY FROM THE UPSLOPE FAVORED LOCATIONS. BY AFTN...PCPN WILL TURN TO
SCT SHOWERY AS STEADIER SYNOPTIC PCPN EXITS AND MID MAY DAYTIME
HEATING THRU CLOUD COVER GENERATES SOME INSTABILITY. DAYTIME HEATING
WILL ALSO WORK TO CHANGE PTYPE TO AT LEAST A MIX OF RAIN/SNOW. THERE
MAY BE SOME LIGHT ADDITIONAL SNOW ACCUM (UNDER AN INCH) OVER THE
HIGHER TERRAIN OF THE NCNTRL IN THE MORNING...BUT NO ADDITIONAL SNOW
ACCUM WILL OCCUR IN THE AFTN. IT WILL BE UNSEASONABLY COLD WITH
TEMPS NOT REACHING 40F IN SOME AREAS NEAR LAKE SUPERIOR...AND
STRUGGLING TO REACH 50F FAR SCNTRL.
FRI NIGHT...COVERAGE OF LINGERING -SHRA/-SHSN WILL DIMINISH AS THE
CLOSED LOW LIFTS SLOWLY TO THE N IN ONTARIO AND CYCLONIC FLOW
WEAKENS.
ON SAT...MID/UPPER LEVEL TROF AXIS WILL CONTINUE TO EXTEND S THRU
THE UPPER LAKES. UNDER TROF...COLD POOL ALOFT AND MID MAY INSOLATION
WILL CONSPIRE TO INCREASE COVERAGE OF SCT SHRA. THE SHOWERS SHOULD
BECOME CONFINED TO MAINLY THE INTERIOR DURING THE DAY WITH DAYTIME
HEATING PROMOTING DESTABILIZATION OVER THE LAND WHILE AREAS NEAR THE
LAKES COME UNDER THE INFLUENCE OF THE STABILIZING MARINE LAYER
BEHIND INLAND PUSHING LAKE BREEZES. BEST CHC OF SHRA WILL BE IN THE
INTERIOR CNTRL. WITH 850MB TEMPS AROUND -4C AT 12Z SAT...PCPN SHOULD
BE MIXED WITH SNOW IN THE MORNING. DAYTIME HEATING WILL THEN CAUSE
THE PTYPE TO BECOME ONLY LIQUID IN THE AFTN...BUT THERE COULD BE
SOME GRAUPEL OR SNOW IN THE AFTN IF MORE VIGOROUS CONVECTION
DEVELOPS.
SAT NIGHT INTO MON...AS UPPER TROF OVER THE GREAT LAKES LIFTS TO THE
NE AND WEAKENS...UPPER RIDGE AND SFC HIGH PRES ARE FCST TO BUILD
OVER THE AREA...BRINGING A PERIOD OF DRY WX. HOWEVER...IT IS NOTED
THAT MEDIUM RANGE GUIDANCE SHOWS A SHORTWAVE TRACKING SE THRU NRN
ONTARIO INTO THE DEPARTING TROF. ECMWF IS STRONGEST WITH FEATURE AND
HAS MORE WIDESPREAD SHRA DEVELOPING ALONG ASSOCIATED COLD FRONT
DROPPING S TOWARD LAKE SUPERIOR. AT THIS POINT...EXPECT STABLE AIR
OVER CHILLY LAKE SUPERIOR TO PREVENT ANY OF THESE SFC BASED -SHRA
FROM REACHING UPPER MI. WITH SOME SUNSHINE...FCST 850MB TEMPS AROUND
2C ON SUN AND 5C ON MON SHOULD ALLOW AFTN TEMPS TO REACH AROUND 60F
AND INTO THE 60S RESPECTIVELY AWAY FROM THE COOLING INFLUENCE OF THE
LAKES. EARLY SUN AND MON MORNING WILL BE CHILLY WITH LIGHT WINDS
NEAR THE SFC RIDGE AXIS ALLOWING TEMPS TO DIP INTO THE 30S AND
POSSIBLY EVEN THE 20S AT SOME OF THE TRADITIONAL INTERIOR COLD
SPOTS.
MON NIGHT THRU WED...MEDIUM RANGE MODELS SHOW SHORTWAVE RIDING OVER
MID/UPPER RIDGE CENTERED IN THE MISSISSIPPI RIVER VALLEY. TIMING OF
FEATURE AND HOW QUICKLY PCPN SPREADS INTO DRY AIR MASS EMANATING
FROM HIGH PRES RIDGE EXTENDING S FROM HUDSON BAY STILL NEED TO BE
WORKED OUT. FOR NOW...WILL CARRY MODEL CONSENSUS CHC POPS GRADUALLY
SPREADING E TO REFLECT THE PCPN POTENTIAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 121 PM EDT THU MAY 15 2014
GUSTY N WINDS THIS AFTN UNDER TIGHTER PRES GRADIENT ON THE WRN FLANK
OF LO PRES MOVING THRU THE CENTRAL LKS WL DIMINISH TNGT WITH THE
CLOSER APRCH OF HI PRES/WEAKER GRADIENT AND LOSS OF DAYTIME HEATING/
MIXING. OTRW...ALTHOUGH SOME FLURRIES MAY FALL AT CMX...VFR
CONDITIONS ASSOCIATED WITH DRY LLVL AIR WL DOMINATE CMX AND IWD THIS
FCST PERIOD. SOME -SN WL FALL THIS AFTN/EVNG AT SAW...WHICH WL BE
CLOSER TO THE TRACK OF THE SFC LO. WITH A FVRBL UPSLOPE N WIND...
EXPECT MVFR WX TO PREDOMINATE AT THIS SITE TNGT. CONDITIONS WL
IMPROVE ON FRI WITH DEPARTURE OF LO/DAYTIME HEATING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 AM EDT THU MAY 15 2014
LOW PRES WILL LIFT FROM NE INDIANA ACROSS LAKE HURON TODAY AND THEN
TO NEAR JAMES BAY BY FRI EVENING. AS A RESULT...EXPECT WINDS TO
INCREASE TO 20-25KT OVER THE E HALF OF LAKE SUPERIOR TODAY/TONIGHT.
WINDS WILL BE LIGHTER OVER THE W. WINDS WILL DIMINISH FRIDAY AS THE
LOW MOVES FARTHER AWAY. FRI NIGHT THRU THE WEEKEND...WINDS WILL BE
UNDER 20KT AND EVEN UNDER 10KT AT TIMES UNDER WEAKER PRES GRADIENT.
LOW PRES DEVELOPING OVER THE PLAINS EARLY NEXT WEEK WILL BRING SOME
INCREASE IN E TO SE WINDS. AS IS NORMALLY THE CASE IN THIS TYPE OF
PATTERN...WILL NEED TO WATCH FOR STRONGER WINDS TO DEVELOP OVER THE
WRN PART OF THE LAKE DUE TO COASTAL CONVERGENCE/FUNNELING.
&&
.HYDROLOGY...
ISSUED AT 1128 AM EDT THU MAY 15 2014
THERE ARE NO FCST POINTS ON AREA RIVERS IN FLOOD. ADVISORIES REMAIN
AT THE STURGEON RIVER AT CHASSELL AS WELL AS WITCH LAKE AND CRYSTAL
FALLS ON THE MICHIGAMME. THE STEADY TO SLOW DOWNWARD TREND TO RIVER
LEVELS WILL CONTINUE THANKS TO LITTLE TO NO ADDITIONAL RUNOFF AND
COOL TEMPERATURES. STILL...THOSE LIVING NEAR RIVERS...CREEKS...AND
STREAMS SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...KC
MARINE...ROLFSON
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1128 AM EDT THU MAY 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 531 AM EDT THU MAY 15 2014
WV LOOP AND ANALYSIS OF RAP H5 HEIGHTS INDICATE DEEP TROUGH FROM
PARENT UPPER LOW OVER EASTERN HUDSON BAY TO ONE SIGNIFICANT TROUGH
DROPPING SE OVER THE NORTHERN PLAINS/MINNESOTA AND ANOTHER LIFTING
NORTHEAST OVER ILLINOIS. PLUME OF DEEP MOISTURE WITH ORIGIN IN THE
EQUATORIAL EAST PACIFIC SURGING NORTH AHEAD OF UPPER TROUGH AND SFC
TROUGH IS SUPPORTING LARGE AREA OF SHOWERS AND SOME TSRA FM SE CONUS
TO CENTRAL GREAT LAKES. THUS FAR PRECIPITATION IS AS CLOSE AS EAST
CENTRAL WI AND FAR EASTERN UPR MICHIGAN. BAND OF RAIN IS ALONG AND
EAST OF H7 FRONTOGENESIS JUST AHEAD OF SHORTWAVE TAKING AIM ON LK
MICHIGAN. 00Z GRB SOUNDING SHOWED DRY AIR BLO H6...AND THIS IS SO FAR
RESTRICTING WESTWARD EXPANSION OF PRECIPITATION. OVER THE MQT CWA
THERE IS A THICK SHIELD OF MID CLOUDS WHICH HAS MAINLY HELD TEMPS UP
IN THE MID 30S TO LOWER 40S. ONLY EXCEPTION IS INTERIOR WEST WHERE
TEMPS HAVE LOCALLY DIPPED INTO THE UPPER 20S.
FOR TODAY...SHORTWAVE OVER ILLINOIS LIFTS ALMOST DUE NORTH TOWARD
CNTRL UPR MICHIGAN BY EARLY AFTN WHILE ADDITIONAL SHORTWAVES DIG
INTO THE TROUGH FARTHER WEST OVER MINNESOTA/UPPER MISSISSIPPI
RIVER VALLEY. EXPECT PRECIP TO THE SE SUPPORTED BY THE FRONT AT H7
TO TRY TO BACK WESTWARD INTO AT LEAST SOUTH CENTRAL AND EASTERN CWA
THROUGH THE MORNING. BASED ON RAP SOUNDINGS AND CURRENT SFC T/TD
COULD SEE MIX OF RAIN/SNOW ONCE PRECIP BEGINS JUST ABOUT ANYWHERE IN
THE EASTERN CWA. PRECIP SHOULD THEN EXPAND FOR ROUGHLY THE EAST HALF
OF CWA EARLY TO MID AFTN AS THE SHORTWAVE/H85-H5 Q-VECTOR CONVERGENCE
AND SWATH OF HIGHER H7-H85 RH ALONG AND WEST OF H85-H7 LOWS...
SHOWING UP AS ENHANCED CLOUD ON WV LOOP OVER IA AND WI..LIFT ACROSS
THE AREA AND AS MAIN SFC LOW LIFTS TOWARD LAKE HURON. NORTH WINDS ON
EDGE OF SFC-H85 LOWS MAY ALLOW FOR EXPANSION OF PRECIP AS FAR WEST
AS NCNTRL UPR MICHIGAN. FORECAST SOUNDINGS INDICATE THAT AS PRECIP
WOULD BEGIN TEMPS WILL FALL INTO THE MID 30S AND SNOW WOULD BE THE
MAIN PTYPE. SNOW ACCUMS WILL BE HELD DOWN BY WARMER GROUND TEMPS AND
SINCE THIS IS OCCURRING DURING THE DAY...BUT WILL NOT BE SURPRISED
TO SEE AN INCH OF SLUSHY SNOW ON GRASSY SURFACES BY EVENING OVER
EAST AS STRONGER LIFT/DYNAMIC COOLING MAY OUTWEIGH THESE OTHER
FACTORS.
MOVING INTO TONIGHT...WIDESPREAD PRECIP...MAINLY IN THE FORM OF
SNOW...WILL BE ONGOING OVER NORTH CENTRAL INTO EAST HALF OF UPR
MICHIGAN AS SHORTWAVE/LARGER SCALE ASCENT IS LIFTING THROUGH.
BEGINNING TO THINK WEST EDGE OF WIDESPREAD PRECIP MAY BE PULLED
FARTHER WEST...PERHAPS TO CMX-LNL LINE AS INITIAL SHORTWAVE MAY
BE NUDGED WEST WITH THE ADDITIONAL INCOMING SHORTWAVE ENERGY ON THE
BACK SIDE OF THE TROUGH. DOES NOT LOOK LIKE COMPLETE PHASING BTWN
THESE FEATURES...BUT IT WILL AFFECT PRECIP PATTERN SOMEWHAT. THINK
THAT THE EVENING TIME FRAME IS WHEN BEST CHANCE FOR ACCUMULATING
SNOW WILL BE FOR NCNTRL UPR MICHIGAN...ESPECIALLY THE HIGHER
TERRAIN AREAS AS THE NORTH WINDS PROVIDE ADDITIONAL UPSLOPE LIFTING.
SOUNDINGS POINT TO SLR/S STRUGGLING TO 10:1 BUT MORE LARGE SCALE
LIFT WILL HELP THIS OUT SOME. CURRENT FORECAST USED BLEND OF GFS AND
ECMWF WITH A BIT OF 00Z NAM TO PICK UP ON THE HIGHER TERRAIN AREAS
BETTER. THIS RESULTED IN 1-2 INCHES OF SNOW TONIGHT. AS HAS BEEN
CONSTANT THEME WITH THIS SYSTEM...THINGS LOOK TO BE CHANGING AGAIN.
BASED ON CURRENT TRENDS IN ENHANCED CLOUDS AND POSSIBLE FARTHER WEST
TRACK OF SYSTEM...THINK THAT THE 06Z NAM RUN WHICH SHOWS ROUGHLY
DOUBLE OF THE TOTAL QPF IT DID ON THE 00Z RUN COULD BE ON THE RIGHT
TRACK. MAY BE OVERPLAYING THINGS SOME THOUGH. IF THIS IDEA IS MORE
IN LINE...THEN AREAS FROM KEWEENAW TO DELTA COUNTY WOULD SEE AROUND
1 INCH OF SNOW TONIGHT...WHILE HIGHER TERRAIN OF NCNTRL IN BARAGA
AND MARQUETTE COUNTIES COULD END UP WITH 2 TO 3 INCHES...MAYBE 4
INCHES.
NO ADVISORY WAS ISSUED ATTM...BUT DAYSHIFT CAN TAKE A LOOK AT LATEST
DATA AND MAKE A CALL IF ONE IS NEEDED. GREATEST CHANCE THAT THE SNOW
WOULD IMPACT ROADS WOULD NOT BE UNTIL LATER TONIGHT AS BLYR
SUFFICIENTLY COOLS...BUT THEN THE QUESTION IS WILL THE SNOWFALL
RATES BE ALL THAT HEAVY OVERNIGHT TONIGHT. GIVEN THE
UNCERTAINTY...EVEN THOUGH IT IS PRETTY MUCH HERE...WILL CONTINUE TO
MENTION IN THE HAZARDOUS WEATHER OUTLOOK AND EHWO GRAPHICS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 531 AM EDT THU MAY 15 2014
ANOMALOUSLY DEEP TROF (500MB HEIGHT ANOMALIES PEAKING AROUND 3
STANDARD DEVIATIONS OVER THE LOWER MISSISSIPPI VALLEY) WITH AXIS
ALONG THE MISSISSIPPI RIVER TO START THE PERIOD WILL LIFT NE AND
WEAKEN OVER THE NEXT SEVERAL DAYS. EARLY NEXT WEEK...THE WEAKENED
TROF WILL EXTEND FROM HUDSON BAY TO NEW ENGLAND WHILE A MID/UPPER
LEVEL RIDGE BUILDS INTO THE WRN GREAT LAKES. RIDGE LOOKS TO REMAIN
IN PLACE FOR PERHAPS A FEW DAYS BEFORE IT IS SUPPRESSED BY ENERGY
ROUNDING RIDGE AND THEN HEADING INTO THE LINGERING NE TROF. AS A
RESULT OF THIS PATTERN EVOLUTION...UNSEASONABLY COLD AIR TO START
THE LONG TERM WILL MODERATE TOWARD NEAR NORMAL MID TO LATE MAY
CONDITIONS EARLY NEXT WEEK. LOOKING OUT FARTHER AHEAD...THERE ARE
STILL NO INDICATIONS OF SUSTAINED ABOVE NORMAL TEMPS SETTING UP IN
THE NEXT WEEK TO 14 DAYS. AFTER PCPN ASSOCIATED WITH THE DEEP TROF
EXITS THIS WEEKEND...SOME DRY DAYS SHOULD SET UP FOR EARLY NEXT
WEEK. HOW LONG THE DRY WEATHER LINGERS WILL DEPEND ON HOW
AGGRESSIVELY SHORTWAVES AND ASSOCIATED PCPN ENCROACH ON DRY AIR MASS
OVER THE GREAT LAKES ASSOCIATED WITH SFC HIGH PRES RIDGE EXTENDING S
FROM HUDSON BAY. IT MAY BE A CASE WHERE SHRA REACH WRN UPPER
MI...BUT THE E STAYS DRY.
BEGINNING FRI...DEEP MOISTURE AND CYCLONIC FLOW SHOULD SUPPORT LIGHT
PCPN (MOSTLY SNOW BASED ON FCST SOUNDINGS) IN THE MORNING...MAINLY
FROM THE KEWEENAW INTO NCNTRL UPPER MI WHERE CYCLONIC UPSLOPE NNW
LOW-LEVEL FLOW WILL AID THE PCPN. HOWEVER...WITH DEEP LAYER QVECTOR
DIVERGENCE SHOWN SWINGING N ACROSS THE AREA IN THE WAKE OF SHORTWAVE
LIFTING N THRU ERN UPPER MI TONIGHT WHICH ALSO LEADS TO BEST DEEP
MOISTURE ALSO SHIFTING N...PCPN WILL BE DIMINISHING...ESPECIALLY
AWAY FROM THE UPSLOPE FAVORED LOCATIONS. BY AFTN...PCPN WILL TURN TO
SCT SHOWERY AS STEADIER SYNOPTIC PCPN EXITS AND MID MAY DAYTIME
HEATING THRU CLOUD COVER GENERATES SOME INSTABILITY. DAYTIME HEATING
WILL ALSO WORK TO CHANGE PTYPE TO AT LEAST A MIX OF RAIN/SNOW. THERE
MAY BE SOME LIGHT ADDITIONAL SNOW ACCUM (UNDER AN INCH) OVER THE
HIGHER TERRAIN OF THE NCNTRL IN THE MORNING...BUT NO ADDITIONAL SNOW
ACCUM WILL OCCUR IN THE AFTN. IT WILL BE UNSEASONABLY COLD WITH
TEMPS NOT REACHING 40F IN SOME AREAS NEAR LAKE SUPERIOR...AND
STRUGGLING TO REACH 50F FAR SCNTRL.
FRI NIGHT...COVERAGE OF LINGERING -SHRA/-SHSN WILL DIMINISH AS THE
CLOSED LOW LIFTS SLOWLY TO THE N IN ONTARIO AND CYCLONIC FLOW
WEAKENS.
ON SAT...MID/UPPER LEVEL TROF AXIS WILL CONTINUE TO EXTEND S THRU
THE UPPER LAKES. UNDER TROF...COLD POOL ALOFT AND MID MAY INSOLATION
WILL CONSPIRE TO INCREASE COVERAGE OF SCT SHRA. THE SHOWERS SHOULD
BECOME CONFINED TO MAINLY THE INTERIOR DURING THE DAY WITH DAYTIME
HEATING PROMOTING DESTABILIZATION OVER THE LAND WHILE AREAS NEAR THE
LAKES COME UNDER THE INFLUENCE OF THE STABILIZING MARINE LAYER
BEHIND INLAND PUSHING LAKE BREEZES. BEST CHC OF SHRA WILL BE IN THE
INTERIOR CNTRL. WITH 850MB TEMPS AROUND -4C AT 12Z SAT...PCPN SHOULD
BE MIXED WITH SNOW IN THE MORNING. DAYTIME HEATING WILL THEN CAUSE
THE PTYPE TO BECOME ONLY LIQUID IN THE AFTN...BUT THERE COULD BE
SOME GRAUPEL OR SNOW IN THE AFTN IF MORE VIGOROUS CONVECTION
DEVELOPS.
SAT NIGHT INTO MON...AS UPPER TROF OVER THE GREAT LAKES LIFTS TO THE
NE AND WEAKENS...UPPER RIDGE AND SFC HIGH PRES ARE FCST TO BUILD
OVER THE AREA...BRINGING A PERIOD OF DRY WX. HOWEVER...IT IS NOTED
THAT MEDIUM RANGE GUIDANCE SHOWS A SHORTWAVE TRACKING SE THRU NRN
ONTARIO INTO THE DEPARTING TROF. ECMWF IS STRONGEST WITH FEATURE AND
HAS MORE WIDESPREAD SHRA DEVELOPING ALONG ASSOCIATED COLD FRONT
DROPPING S TOWARD LAKE SUPERIOR. AT THIS POINT...EXPECT STABLE AIR
OVER CHILLY LAKE SUPERIOR TO PREVENT ANY OF THESE SFC BASED -SHRA
FROM REACHING UPPER MI. WITH SOME SUNSHINE...FCST 850MB TEMPS AROUND
2C ON SUN AND 5C ON MON SHOULD ALLOW AFTN TEMPS TO REACH AROUND 60F
AND INTO THE 60S RESPECTIVELY AWAY FROM THE COOLING INFLUENCE OF THE
LAKES. EARLY SUN AND MON MORNING WILL BE CHILLY WITH LIGHT WINDS
NEAR THE SFC RIDGE AXIS ALLOWING TEMPS TO DIP INTO THE 30S AND
POSSIBLY EVEN THE 20S AT SOME OF THE TRADITIONAL INTERIOR COLD
SPOTS.
MON NIGHT THRU WED...MEDIUM RANGE MODELS SHOW SHORTWAVE RIDING OVER
MID/UPPER RIDGE CENTERED IN THE MISSISSIPPI RIVER VALLEY. TIMING OF
FEATURE AND HOW QUICKLY PCPN SPREADS INTO DRY AIR MASS EMANATING
FROM HIGH PRES RIDGE EXTENDING S FROM HUDSON BAY STILL NEED TO BE
WORKED OUT. FOR NOW...WILL CARRY MODEL CONSENSUS CHC POPS GRADUALLY
SPREADING E TO REFLECT THE PCPN POTENTIAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 744 AM EDT THU MAY 15 2014
WINDS WILL BE GUSTY FM THE NORTH AS PRESSURE GRADIENT TIGHTENS BTWN
LOW LIFTING ACROSS THE CENTRAL GREAT LAKES AND HIGH PRESSURE OVER
THE NORTHERN PLAINS. LIGHT RAIN/SNOW WILL BEGIN TO WORK INTO CNTRL
UPR MICHIGAN...INCLUDING KSAW...THIS AFTN. MAINLY SNOW IS EXPECTED
TONIGHT AND THIS WILL SPREAD TO KCMX LATER TONIGHT. KIWD SHOULD
REMAIN CLEAR OF ANY RAIN OR SNOW. CONDITIONS START OUT VFR AT ALL
TAF SITES TODAY. GENERALLY EXPECT VFR CONDITIONS TO REMAIN AT KIWD
WHILE MVFR DEVELOPS AT KCMX TONIGHT. LOWEST CONDITIONS AT KSAW...DOWN
TO IFR AT TIMES LATE TODAY/THIS EVENING. IMPROVING TREND WILL BEGIN
TO DEVELOP LATE TONIGHT THOUGH AS THE LOW PRESSURE SYSTEM PULLS AWAY
FM THE REGION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 AM EDT THU MAY 15 2014
LOW PRES WILL LIFT FROM NE INDIANA ACROSS LAKE HURON TODAY AND THEN
TO NEAR JAMES BAY BY FRI EVENING. AS A RESULT...EXPECT WINDS TO
INCREASE TO 20-25KT OVER THE E HALF OF LAKE SUPERIOR TODAY/TONIGHT.
WINDS WILL BE LIGHTER OVER THE W. WINDS WILL DIMINISH FRIDAY AS THE
LOW MOVES FARTHER AWAY. FRI NIGHT THRU THE WEEKEND...WINDS WILL BE
UNDER 20KT AND EVEN UNDER 10KT AT TIMES UNDER WEAKER PRES GRADIENT.
LOW PRES DEVELOPING OVER THE PLAINS EARLY NEXT WEEK WILL BRING SOME
INCREASE IN E TO SE WINDS. AS IS NORMALLY THE CASE IN THIS TYPE OF
PATTERN...WILL NEED TO WATCH FOR STRONGER WINDS TO DEVELOP OVER THE
WRN PART OF THE LAKE DUE TO COASTAL CONVERGENCE/FUNNELING.
&&
.HYDROLOGY...
ISSUED AT 1128 AM EDT THU MAY 15 2014
THERE ARE NO FCST POINTS ON AREA RIVERS IN FLOOD. ADVISORIES REMAIN
AT THE STURGEON RIVER AT CHASSELL AS WELL AS WITCH LAKE AND CRYSTAL
FALLS ON THE MICHIGAMME. THE STEADY TO SLOW DOWNWARD TREND TO RIVER
LEVELS WILL CONTINUE THANKS TO LITTLE TO NO ADDITIONAL RUNOFF AND
COOL TEMPERATURES. STILL...THOSE LIVING NEAR RIVERS...CREEKS...AND
STREAMS SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...JLA
MARINE...ROLFSON
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
747 AM EDT THU MAY 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 531 AM EDT THU MAY 15 2014
WV LOOP AND ANALYSIS OF RAP H5 HEIGHTS INDICATE DEEP TROUGH FROM
PARENT UPPER LOW OVER EASTERN HUDSON BAY TO ONE SIGNIFICANT TROUGH
DROPPING SE OVER THE NORTHERN PLAINS/MINNESOTA AND ANOTHER LIFTING
NORTHEAST OVER ILLINOIS. PLUME OF DEEP MOISTURE WITH ORIGIN IN THE
EQUATORIAL EAST PACIFIC SURGING NORTH AHEAD OF UPPER TROUGH AND SFC
TROUGH IS SUPPORTING LARGE AREA OF SHOWERS AND SOME TSRA FM SE CONUS
TO CENTRAL GREAT LAKES. THUS FAR PRECIPITATION IS AS CLOSE AS EAST
CENTRAL WI AND FAR EASTERN UPR MICHIGAN. BAND OF RAIN IS ALONG AND
EAST OF H7 FRONTOGENESIS JUST AHEAD OF SHORTWAVE TAKING AIM ON LK
MICHIGAN. 00Z GRB SOUNDING SHOWED DRY AIR BLO H6...AND THIS IS SO FAR
RESTRICTING WESTWARD EXPANSION OF PRECIPITATION. OVER THE MQT CWA
THERE IS A THICK SHIELD OF MID CLOUDS WHICH HAS MAINLY HELD TEMPS UP
IN THE MID 30S TO LOWER 40S. ONLY EXCEPTION IS INTERIOR WEST WHERE
TEMPS HAVE LOCALLY DIPPED INTO THE UPPER 20S.
FOR TODAY...SHORTWAVE OVER ILLINOIS LIFTS ALMOST DUE NORTH TOWARD
CNTRL UPR MICHIGAN BY EARLY AFTN WHILE ADDITIONAL SHORTWAVES DIG
INTO THE TROUGH FARTHER WEST OVER MINNESOTA/UPPER MISSISSIPPI
RIVER VALLEY. EXPECT PRECIP TO THE SE SUPPORTED BY THE FRONT AT H7
TO TRY TO BACK WESTWARD INTO AT LEAST SOUTH CENTRAL AND EASTERN CWA
THROUGH THE MORNING. BASED ON RAP SOUNDINGS AND CURRENT SFC T/TD
COULD SEE MIX OF RAIN/SNOW ONCE PRECIP BEGINS JUST ABOUT ANYWHERE IN
THE EASTERN CWA. PRECIP SHOULD THEN EXPAND FOR ROUGHLY THE EAST HALF
OF CWA EARLY TO MID AFTN AS THE SHORTWAVE/H85-H5 Q-VECTOR CONVERGENCE
AND SWATH OF HIGHER H7-H85 RH ALONG AND WEST OF H85-H7 LOWS...
SHOWING UP AS ENHANCED CLOUD ON WV LOOP OVER IA AND WI..LIFT ACROSS
THE AREA AND AS MAIN SFC LOW LIFTS TOWARD LAKE HURON. NORTH WINDS ON
EDGE OF SFC-H85 LOWS MAY ALLOW FOR EXPANSION OF PRECIP AS FAR WEST
AS NCNTRL UPR MICHIGAN. FORECAST SOUNDINGS INDICATE THAT AS PRECIP
WOULD BEGIN TEMPS WILL FALL INTO THE MID 30S AND SNOW WOULD BE THE
MAIN PTYPE. SNOW ACCUMS WILL BE HELD DOWN BY WARMER GROUND TEMPS AND
SINCE THIS IS OCCURRING DURING THE DAY...BUT WILL NOT BE SURPRISED
TO SEE AN INCH OF SLUSHY SNOW ON GRASSY SURFACES BY EVENING OVER
EAST AS STRONGER LIFT/DYNAMIC COOLING MAY OUTWEIGH THESE OTHER
FACTORS.
MOVING INTO TONIGHT...WIDESPREAD PRECIP...MAINLY IN THE FORM OF
SNOW...WILL BE ONGOING OVER NORTH CENTRAL INTO EAST HALF OF UPR
MICHIGAN AS SHORTWAVE/LARGER SCALE ASCENT IS LIFTING THROUGH.
BEGINNING TO THINK WEST EDGE OF WIDESPREAD PRECIP MAY BE PULLED
FARTHER WEST...PERHAPS TO CMX-LNL LINE AS INITIAL SHORTWAVE MAY
BE NUDGED WEST WITH THE ADDITIONAL INCOMING SHORTWAVE ENERGY ON THE
BACK SIDE OF THE TROUGH. DOES NOT LOOK LIKE COMPLETE PHASING BTWN
THESE FEATURES...BUT IT WILL AFFECT PRECIP PATTERN SOMEWHAT. THINK
THAT THE EVENING TIME FRAME IS WHEN BEST CHANCE FOR ACCUMULATING
SNOW WILL BE FOR NCNTRL UPR MICHIGAN...ESPECIALLY THE HIGHER
TERRAIN AREAS AS THE NORTH WINDS PROVIDE ADDITIONAL UPSLOPE LIFTING.
SOUNDINGS POINT TO SLR/S STRUGGLING TO 10:1 BUT MORE LARGE SCALE
LIFT WILL HELP THIS OUT SOME. CURRENT FORECAST USED BLEND OF GFS AND
ECMWF WITH A BIT OF 00Z NAM TO PICK UP ON THE HIGHER TERRAIN AREAS
BETTER. THIS RESULTED IN 1-2 INCHES OF SNOW TONIGHT. AS HAS BEEN
CONSTANT THEME WITH THIS SYSTEM...THINGS LOOK TO BE CHANGING AGAIN.
BASED ON CURRENT TRENDS IN ENHANCED CLOUDS AND POSSIBLE FARTHER WEST
TRACK OF SYSTEM...THINK THAT THE 06Z NAM RUN WHICH SHOWS ROUGHLY
DOUBLE OF THE TOTAL QPF IT DID ON THE 00Z RUN COULD BE ON THE RIGHT
TRACK. MAY BE OVERPLAYING THINGS SOME THOUGH. IF THIS IDEA IS MORE
IN LINE...THEN AREAS FROM KEWEENAW TO DELTA COUNTY WOULD SEE AROUND
1 INCH OF SNOW TONIGHT...WHILE HIGHER TERRAIN OF NCNTRL IN BARAGA
AND MARQUETTE COUNTIES COULD END UP WITH 2 TO 3 INCHES...MAYBE 4
INCHES.
NO ADVISORY WAS ISSUED ATTM...BUT DAYSHIFT CAN TAKE A LOOK AT LATEST
DATA AND MAKE A CALL IF ONE IS NEEDED. GREATEST CHANCE THAT THE SNOW
WOULD IMPACT ROADS WOULD NOT BE UNTIL LATER TONIGHT AS BLYR
SUFFICIENTLY COOLS...BUT THEN THE QUESTION IS WILL THE SNOWFALL
RATES BE ALL THAT HEAVY OVERNIGHT TONIGHT. GIVEN THE
UNCERTAINTY...EVEN THOUGH IT IS PRETTY MUCH HERE...WILL CONTINUE TO
MENTION IN THE HAZARDOUS WEATHER OUTLOOK AND EHWO GRAPHICS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 531 AM EDT THU MAY 15 2014
ANOMALOUSLY DEEP TROF (500MB HEIGHT ANOMALIES PEAKING AROUND 3
STANDARD DEVIATIONS OVER THE LOWER MISSISSIPPI VALLEY) WITH AXIS
ALONG THE MISSISSIPPI RIVER TO START THE PERIOD WILL LIFT NE AND
WEAKEN OVER THE NEXT SEVERAL DAYS. EARLY NEXT WEEK...THE WEAKENED
TROF WILL EXTEND FROM HUDSON BAY TO NEW ENGLAND WHILE A MID/UPPER
LEVEL RIDGE BUILDS INTO THE WRN GREAT LAKES. RIDGE LOOKS TO REMAIN
IN PLACE FOR PERHAPS A FEW DAYS BEFORE IT IS SUPPRESSED BY ENERGY
ROUNDING RIDGE AND THEN HEADING INTO THE LINGERING NE TROF. AS A
RESULT OF THIS PATTERN EVOLUTION...UNSEASONABLY COLD AIR TO START
THE LONG TERM WILL MODERATE TOWARD NEAR NORMAL MID TO LATE MAY
CONDITIONS EARLY NEXT WEEK. LOOKING OUT FARTHER AHEAD...THERE ARE
STILL NO INDICATIONS OF SUSTAINED ABOVE NORMAL TEMPS SETTING UP IN
THE NEXT WEEK TO 14 DAYS. AFTER PCPN ASSOCIATED WITH THE DEEP TROF
EXITS THIS WEEKEND...SOME DRY DAYS SHOULD SET UP FOR EARLY NEXT
WEEK. HOW LONG THE DRY WEATHER LINGERS WILL DEPEND ON HOW
AGGRESSIVELY SHORTWAVES AND ASSOCIATED PCPN ENCROACH ON DRY AIR MASS
OVER THE GREAT LAKES ASSOCIATED WITH SFC HIGH PRES RIDGE EXTENDING S
FROM HUDSON BAY. IT MAY BE A CASE WHERE SHRA REACH WRN UPPER
MI...BUT THE E STAYS DRY.
BEGINNING FRI...DEEP MOISTURE AND CYCLONIC FLOW SHOULD SUPPORT LIGHT
PCPN (MOSTLY SNOW BASED ON FCST SOUNDINGS) IN THE MORNING...MAINLY
FROM THE KEWEENAW INTO NCNTRL UPPER MI WHERE CYCLONIC UPSLOPE NNW
LOW-LEVEL FLOW WILL AID THE PCPN. HOWEVER...WITH DEEP LAYER QVECTOR
DIVERGENCE SHOWN SWINGING N ACROSS THE AREA IN THE WAKE OF SHORTWAVE
LIFTING N THRU ERN UPPER MI TONIGHT WHICH ALSO LEADS TO BEST DEEP
MOISTURE ALSO SHIFTING N...PCPN WILL BE DIMINISHING...ESPECIALLY
AWAY FROM THE UPSLOPE FAVORED LOCATIONS. BY AFTN...PCPN WILL TURN TO
SCT SHOWERY AS STEADIER SYNOPTIC PCPN EXITS AND MID MAY DAYTIME
HEATING THRU CLOUD COVER GENERATES SOME INSTABILITY. DAYTIME HEATING
WILL ALSO WORK TO CHANGE PTYPE TO AT LEAST A MIX OF RAIN/SNOW. THERE
MAY BE SOME LIGHT ADDITIONAL SNOW ACCUM (UNDER AN INCH) OVER THE
HIGHER TERRAIN OF THE NCNTRL IN THE MORNING...BUT NO ADDITIONAL SNOW
ACCUM WILL OCCUR IN THE AFTN. IT WILL BE UNSEASONABLY COLD WITH
TEMPS NOT REACHING 40F IN SOME AREAS NEAR LAKE SUPERIOR...AND
STRUGGLING TO REACH 50F FAR SCNTRL.
FRI NIGHT...COVERAGE OF LINGERING -SHRA/-SHSN WILL DIMINISH AS THE
CLOSED LOW LIFTS SLOWLY TO THE N IN ONTARIO AND CYCLONIC FLOW
WEAKENS.
ON SAT...MID/UPPER LEVEL TROF AXIS WILL CONTINUE TO EXTEND S THRU
THE UPPER LAKES. UNDER TROF...COLD POOL ALOFT AND MID MAY INSOLATION
WILL CONSPIRE TO INCREASE COVERAGE OF SCT SHRA. THE SHOWERS SHOULD
BECOME CONFINED TO MAINLY THE INTERIOR DURING THE DAY WITH DAYTIME
HEATING PROMOTING DESTABILIZATION OVER THE LAND WHILE AREAS NEAR THE
LAKES COME UNDER THE INFLUENCE OF THE STABILIZING MARINE LAYER
BEHIND INLAND PUSHING LAKE BREEZES. BEST CHC OF SHRA WILL BE IN THE
INTERIOR CNTRL. WITH 850MB TEMPS AROUND -4C AT 12Z SAT...PCPN SHOULD
BE MIXED WITH SNOW IN THE MORNING. DAYTIME HEATING WILL THEN CAUSE
THE PTYPE TO BECOME ONLY LIQUID IN THE AFTN...BUT THERE COULD BE
SOME GRAUPEL OR SNOW IN THE AFTN IF MORE VIGOROUS CONVECTION
DEVELOPS.
SAT NIGHT INTO MON...AS UPPER TROF OVER THE GREAT LAKES LIFTS TO THE
NE AND WEAKENS...UPPER RIDGE AND SFC HIGH PRES ARE FCST TO BUILD
OVER THE AREA...BRINGING A PERIOD OF DRY WX. HOWEVER...IT IS NOTED
THAT MEDIUM RANGE GUIDANCE SHOWS A SHORTWAVE TRACKING SE THRU NRN
ONTARIO INTO THE DEPARTING TROF. ECMWF IS STRONGEST WITH FEATURE AND
HAS MORE WIDESPREAD SHRA DEVELOPING ALONG ASSOCIATED COLD FRONT
DROPPING S TOWARD LAKE SUPERIOR. AT THIS POINT...EXPECT STABLE AIR
OVER CHILLY LAKE SUPERIOR TO PREVENT ANY OF THESE SFC BASED -SHRA
FROM REACHING UPPER MI. WITH SOME SUNSHINE...FCST 850MB TEMPS AROUND
2C ON SUN AND 5C ON MON SHOULD ALLOW AFTN TEMPS TO REACH AROUND 60F
AND INTO THE 60S RESPECTIVELY AWAY FROM THE COOLING INFLUENCE OF THE
LAKES. EARLY SUN AND MON MORNING WILL BE CHILLY WITH LIGHT WINDS
NEAR THE SFC RIDGE AXIS ALLOWING TEMPS TO DIP INTO THE 30S AND
POSSIBLY EVEN THE 20S AT SOME OF THE TRADITIONAL INTERIOR COLD
SPOTS.
MON NIGHT THRU WED...MEDIUM RANGE MODELS SHOW SHORTWAVE RIDING OVER
MID/UPPER RIDGE CENTERED IN THE MISSISSIPPI RIVER VALLEY. TIMING OF
FEATURE AND HOW QUICKLY PCPN SPREADS INTO DRY AIR MASS EMANATING
FROM HIGH PRES RIDGE EXTENDING S FROM HUDSON BAY STILL NEED TO BE
WORKED OUT. FOR NOW...WILL CARRY MODEL CONSENSUS CHC POPS GRADUALLY
SPREADING E TO REFLECT THE PCPN POTENTIAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 744 AM EDT THU MAY 15 2014
WINDS WILL BE GUSTY FM THE NORTH AS PRESSURE GRADIENT TIGHTENS BTWN
LOW LIFTING ACROSS THE CENTRAL GREAT LAKES AND HIGH PRESSURE OVER
THE NORTHERN PLAINS. LIGHT RAIN/SNOW WILL BEGIN TO WORK INTO CNTRL
UPR MICHIGAN...INCLUDING KSAW...THIS AFTN. MAINLY SNOW IS EXPECTED
TONIGHT AND THIS WILL SPREAD TO KCMX LATER TONIGHT. KIWD SHOULD
REMAIN CLEAR OF ANY RAIN OR SNOW. CONDITIONS START OUT VFR AT ALL
TAF SITES TODAY. GENERALLY EXPECT VFR CONDITIONS TO REMAIN AT KIWD
WHILE MVFR DEVELOPS AT KCMX TONIGHT. LOWEST CONDITIONS AT KSAW...DOWN
TO IFR AT TIMES LATE TODAY/THIS EVENING. IMPROVING TREND WILL BEGIN
TO DEVELOP LATE TONIGHT THOUGH AS THE LOW PRESSURE SYSTEM PULLS AWAY
FM THE REGION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 AM EDT THU MAY 15 2014
LOW PRES WILL LIFT FROM NE INDIANA ACROSS LAKE HURON TODAY AND THEN
TO NEAR JAMES BAY BY FRI EVENING. AS A RESULT...EXPECT WINDS TO
INCREASE TO 20-25KT OVER THE E HALF OF LAKE SUPERIOR TODAY/TONIGHT.
WINDS WILL BE LIGHTER OVER THE W. WINDS WILL DIMINISH FRIDAY AS THE
LOW MOVES FARTHER AWAY. FRI NIGHT THRU THE WEEKEND...WINDS WILL BE
UNDER 20KT AND EVEN UNDER 10KT AT TIMES UNDER WEAKER PRES GRADIENT.
LOW PRES DEVELOPING OVER THE PLAINS EARLY NEXT WEEK WILL BRING SOME
INCREASE IN E TO SE WINDS. AS IS NORMALLY THE CASE IN THIS TYPE OF
PATTERN...WILL NEED TO WATCH FOR STRONGER WINDS TO DEVELOP OVER THE
WRN PART OF THE LAKE DUE TO COASTAL CONVERGENCE/FUNNELING.
&&
.HYDROLOGY...
ISSUED AT 531 AM EDT THU MAY 15 2014
THE MAIN RIVERS OF CONCERN CONTINUE TO BE OVER THE W HALF OF UPPER
MI. NO FLOOD WARNINGS ARE IN EFFECT. ONLY FLOOD ADVYS REMAIN FOR
STURGEON RIVER AT CHASSELL AND FOR THE MICHIGAMME RIVER AT WITCH
LAKE...REPUBLIC AND CRYSTAL FALLS.
FORTUNATELY...PCPN EXPECTED OVER THE NEXT FEW DAYS...OCCURRING
MOSTLY TODAY THRU FRI MORNING...WILL BE ON THE LIGHTER SIDE SO THAT
RIVERS SHOULD HAVE LITTLE OR NO RESPONSE. AS A RESULT...AN OVERALL
SLOW DOWNWARD TREND SHOULD BE THE RULE ON ALL RIVERS/STREAMS OVER
THE NEXT FEW DAYS. DRY WEATHER EARLY NEXT WEEK SHOULD FURTHER AID
THE DECLINE OF RIVER LEVELS.
THOSE LIVING NEAR RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO
MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...JLA
MARINE...ROLFSON
HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
532 AM EDT THU MAY 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 531 AM EDT THU MAY 15 2014
WV LOOP AND ANALYSIS OF RAP H5 HEIGHTS INDICATE DEEP TROUGH FROM
PARENT UPPER LOW OVER EASTERN HUDSON BAY TO ONE SIGNIFICANT TROUGH
DROPPING SE OVER THE NORTHERN PLAINS/MINNESOTA AND ANOTHER LIFTING
NORTHEAST OVER ILLINOIS. PLUME OF DEEP MOISTURE WITH ORIGIN IN THE
EQUATORIAL EAST PACIFIC SURGING NORTH AHEAD OF UPPER TROUGH AND SFC
TROUGH IS SUPPORTING LARGE AREA OF SHOWERS AND SOME TSRA FM SE CONUS
TO CENTRL GREAT LAKES. THUS FAR PRECIPITATION IS AS CLOSE AS EAST
CENTRAL WI AND FAR EASTERN UPR MICHIGAN. BAND OF RAIN IS ALONG AND
EAST OF H7 FRONTOGENESIS JUST AHEAD OF SHORTWAVE TAKING AIM ON LK
MICHIGAN. 00Z GRB SOUNDING SHOWED DRY AIR BLO H6...AND THIS IS SO
FAR RESTRICTING WESTWARD EXPANSION OF PRECIPITATION. OVER THE MQT
CWA THERE IS A THICK SHIELD OF MID CLOUDS WHICH HAS MAINLY HELD
TEMPS UP IN THE MID 30S TO LOWER 40S. ONLY EXCEPTION IS INTERIOR
WEST WHERE TEMPS HAVE LOCALLY DIPPED INTO THE UPPER 20S.
FOR TODAY...SHORTWAVE OVER ILLINOIS LIFTS ALMOST DUE NORTH TOWARD
CNTRL UPR MICHIGAN BY EARLY AFTN WHILE ADDITIONAL SHORTWAVES DIG
INTO THE TROUGH FARTHER WEST OVER MINNESOTA/UPPER MISSISSIPPI
RIVER VALLEY. EXPECT PRECIP TO THE SE SUPPORTED BY THE FRONT AT H7
TO TRY TO BACK WESTWARD INTO AT LEAST SOUTH CENTRAL AND EASTERN CWA
THROUGH THE MORNING. BASED ON RAP SOUNDINGS AND CURRENT SFC T/TD
COULD SEE MIX OF RAIN/SNOW ONCE PRECIP BEGINS JUST ABOUT ANYWHERE IN
THE EASTERN CWA. PRECIP SHOULD THEN EXPAND FOR ROUGHLY THE EAST HALF
OF CWA EARLY TO MID AFTN AS THE SHORTWAVE/H85-H5 Q-VECTOR CONVERGENCE
AND SWATH OF HIGHER H7-H85 RH ALONG AND WEST OF H85-H7 LOWS...
SHOWING UP AS ENHANCED CLOUD ON WV LOOP OVER IA AND WI..LIFT ACROSS
THE AREA AND AS MAIN SFC LOW LIFTS TOWARD LAKE HURON. NORTH WINDS ON
EDGE OF SFC-H85 LOWS MAY ALLOW FOR EXPANSION OF PRECIP AS FAR WEST
AS NCNTRL UPR MICHIGAN. FORECAST SOUNDINGS INDICATE THAT AS PRECIP
WOULD BEGIN TEMPS WILL FALL INTO THE MID 30S AND SNOW WOULD BE THE
MAIN PTYPE. SNOW ACCUMS WILL BE HELD DOWN BY WARMER GROUND TEMPS AND
SINCE THIS IS OCCURRING DURING THE DAY...BUT WILL NOT BE SURPRISED
TO SEE AN INCH OF SLUSHY SNOW ON GRASSY SURFACES BY EVENING OVER
EAST AS STRONGER LIFT/DYNAMIC COOLING MAY OUTWEIGH THESE OTHER
FACTORS.
MOVING INTO TONIGHT...WIDESPREAD PRECIP...MAINLY IN THE FORM OF
SNOW...WILL BE ONGOING OVER NORTH CENTRAL INTO EAST HALF OF UPR
MICHIGAN AS SHORTWAVE/LARGER SCALE ASCENT IS LIFTING THROUGH.
BEGINNING TO THINK WEST EDGE OF WIDESPREAD PRECIP MAY BE PULLED
FARTHER WEST...PERHAPS TO CMX-LNL LINE AS INITIAL SHORTWAVE MAY
BE NUDGED WEST WITH THE ADDITIONAL INCOMING SHORTWAVE ENERGY ON THE
BACK SIDE OF THE TROUGH. DOES NOT LOOK LIKE COMPLETE PHASING BTWN
THESE FEATURES...BUT IT WILL AFFECT PRECIP PATTERN SOMEWHAT. THINK
THAT THE EVENING TIME FRAME IS WHEN BEST CHANCE FOR ACCUMULATING
SNOW WILL BE FOR NCNTRL UPR MICHIGAN...ESPECIALLY THE HIGHER
TERRAIN AREAS AS THE NORTH WINDS PROVIDE ADDITIONAL UPSLOPE LIFTING.
SOUNDINGS POINT TO SLR/S STRUGGLING TO 10:1 BUT MORE LARGE SCALE
LIFT WILL HELP THIS OUT SOME. CURRENT FORECAST USED BLEND OF GFS AND
ECMWF WITH A BIT OF 00Z NAM TO PICK UP ON THE HIGHER TERRAIN AREAS
BETTER. THIS RESULTED IN 1-2 INCHES OF SNOW TONIGHT. AS HAS BEEN
CONSTANT THEME WITH THIS SYSTEM...THINGS LOOK TO BE CHANGING AGAIN.
BASED ON CURRENT TRENDS IN ENHANCED CLOUDS AND POSSIBLE FARTHER WEST
TRACK OF SYSTEM...THINK THAT THE 06Z NAM RUN WHICH SHOWS ROUGHLY
DOUBLE OF THE TOTAL QPF IT DID ON THE 00Z RUN COULD BE ON THE RIGHT
TRACK. MAY BE OVERPLAYING THINGS SOME THOUGH. IF THIS IDEA IS MORE
IN LINE...THEN AREAS FROM KEWEENAW TO DELTA COUNTY WOULD SEE AROUND
1 INCH OF SNOW TONIGHT...WHILE HIGHER TERRAIN OF NCNTRL IN BARAGA
AND MARQUETTE COUNTIES COULD END UP WITH 2 TO 3 INCHES...MAYBE 4
INCHES.
NO ADVISORY WAS ISSUED ATTM...BUT DAYSHIFT CAN TAKE A LOOK AT LATEST
DATA AND MAKE A CALL IF ONE IS NEEDED. GREATEST CHANCE THAT THE SNOW
WOULD IMPACT ROADS WOULD NOT BE UNTIL LATER TONIGHT AS BLYR
SUFFICIENTLY COOLS...BUT THEN THE QUESTION IS WILL THE SNOWFALL
RATES BE ALL THAT HEAVY OVERNIGHT TONIGHT. GIVEN THE
UNCERTAINTY...EVEN THOUGH IT IS PRETTY MUCH HERE...WILL CONTINUE TO
MENTION IN THE HAZARDOUS WEATHER OUTLOOK AND EHWO GRAPHICS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 531 AM EDT THU MAY 15 2014
ANOMALOUSLY DEEP TROF (500MB HEIGHT ANOMALIES PEAKING AROUND 3
STANDARD DEVIATIONS OVER THE LOWER MISSISSIPPI VALLEY) WITH AXIS
ALONG THE MISSISSIPPI RIVER TO START THE PERIOD WILL LIFT NE AND
WEAKEN OVER THE NEXT SEVERAL DAYS. EARLY NEXT WEEK...THE WEAKENED
TROF WILL EXTEND FROM HUDSON BAY TO NEW ENGLAND WHILE A MID/UPPER
LEVEL RIDGE BUILDS INTO THE WRN GREAT LAKES. RIDGE LOOKS TO REMAIN
IN PLACE FOR PERHAPS A FEW DAYS BEFORE IT IS SUPPRESSED BY ENERGY
ROUNDING RIDGE AND THEN HEADING INTO THE LINGERING NE TROF. AS A
RESULT OF THIS PATTERN EVOLUTION...UNSEASONABLY COLD AIR TO START
THE LONG TERM WILL MODERATE TOWARD NEAR NORMAL MID TO LATE MAY
CONDITIONS EARLY NEXT WEEK. LOOKING OUT FARTHER AHEAD...THERE ARE
STILL NO INDICATIONS OF SUSTAINED ABOVE NORMAL TEMPS SETTING UP IN
THE NEXT WEEK TO 14 DAYS. AFTER PCPN ASSOCIATED WITH THE DEEP TROF
EXITS THIS WEEKEND...SOME DRY DAYS SHOULD SET UP FOR EARLY NEXT
WEEK. HOW LONG THE DRY WEATHER LINGERS WILL DEPEND ON HOW
AGGRESSIVELY SHORTWAVES AND ASSOCIATED PCPN ENCROACH ON DRY AIR MASS
OVER THE GREAT LAKES ASSOCIATED WITH SFC HIGH PRES RIDGE EXTENDING S
FROM HUDSON BAY. IT MAY BE A CASE WHERE SHRA REACH WRN UPPER
MI...BUT THE E STAYS DRY.
BEGINNING FRI...DEEP MOISTURE AND CYCLONIC FLOW SHOULD SUPPORT LIGHT
PCPN (MOSTLY SNOW BASED ON FCST SOUNDINGS) IN THE MORNING...MAINLY
FROM THE KEWEENAW INTO NCNTRL UPPER MI WHERE CYCLONIC UPSLOPE NNW
LOW-LEVEL FLOW WILL AID THE PCPN. HOWEVER...WITH DEEP LAYER QVECTOR
DIVERGENCE SHOWN SWINGING N ACROSS THE AREA IN THE WAKE OF SHORTWAVE
LIFTING N THRU ERN UPPER MI TONIGHT WHICH ALSO LEADS TO BEST DEEP
MOISTURE ALSO SHIFTING N...PCPN WILL BE DIMINISHING...ESPECIALLY
AWAY FROM THE UPSLOPE FAVORED LOCATIONS. BY AFTN...PCPN WILL TURN TO
SCT SHOWERY AS STEADIER SYNOPTIC PCPN EXITS AND MID MAY DAYTIME
HEATING THRU CLOUD COVER GENERATES SOME INSTABILITY. DAYTIME HEATING
WILL ALSO WORK TO CHANGE PTYPE TO AT LEAST A MIX OF RAIN/SNOW. THERE
MAY BE SOME LIGHT ADDITIONAL SNOW ACCUM (UNDER AN INCH) OVER THE
HIGHER TERRAIN OF THE NCNTRL IN THE MORNING...BUT NO ADDITIONAL SNOW
ACCUM WILL OCCUR IN THE AFTN. IT WILL BE UNSEASONABLY COLD WITH
TEMPS NOT REACHING 40F IN SOME AREAS NEAR LAKE SUPERIOR...AND
STRUGGLING TO REACH 50F FAR SCNTRL.
FRI NIGHT...COVERAGE OF LINGERING -SHRA/-SHSN WILL DIMINISH AS THE
CLOSED LOW LIFTS SLOWLY TO THE N IN ONTARIO AND CYCLONIC FLOW
WEAKENS.
ON SAT...MID/UPPER LEVEL TROF AXIS WILL CONTINUE TO EXTEND S THRU
THE UPPER LAKES. UNDER TROF...COLD POOL ALOFT AND MID MAY INSOLATION
WILL CONSPIRE TO INCREASE COVERAGE OF SCT SHRA. THE SHOWERS SHOULD
BECOME CONFINED TO MAINLY THE INTERIOR DURING THE DAY WITH DAYTIME
HEATING PROMOTING DESTABILIZATION OVER THE LAND WHILE AREAS NEAR THE
LAKES COME UNDER THE INFLUENCE OF THE STABILIZING MARINE LAYER
BEHIND INLAND PUSHING LAKE BREEZES. BEST CHC OF SHRA WILL BE IN THE
INTERIOR CNTRL. WITH 850MB TEMPS AROUND -4C AT 12Z SAT...PCPN SHOULD
BE MIXED WITH SNOW IN THE MORNING. DAYTIME HEATING WILL THEN CAUSE
THE PTYPE TO BECOME ONLY LIQUID IN THE AFTN...BUT THERE COULD BE
SOME GRAUPEL OR SNOW IN THE AFTN IF MORE VIGOROUS CONVECTION
DEVELOPS.
SAT NIGHT INTO MON...AS UPPER TROF OVER THE GREAT LAKES LIFTS TO THE
NE AND WEAKENS...UPPER RIDGE AND SFC HIGH PRES ARE FCST TO BUILD
OVER THE AREA...BRINGING A PERIOD OF DRY WX. HOWEVER...IT IS NOTED
THAT MEDIUM RANGE GUIDANCE SHOWS A SHORTWAVE TRACKING SE THRU NRN
ONTARIO INTO THE DEPARTING TROF. ECMWF IS STRONGEST WITH FEATURE AND
HAS MORE WIDESPREAD SHRA DEVELOPING ALONG ASSOCIATED COLD FRONT
DROPPING S TOWARD LAKE SUPERIOR. AT THIS POINT...EXPECT STABLE AIR
OVER CHILLY LAKE SUPERIOR TO PREVENT ANY OF THESE SFC BASED -SHRA
FROM REACHING UPPER MI. WITH SOME SUNSHINE...FCST 850MB TEMPS AROUND
2C ON SUN AND 5C ON MON SHOULD ALLOW AFTN TEMPS TO REACH AROUND 60F
AND INTO THE 60S RESPECTIVELY AWAY FROM THE COOLING INFLUENCE OF THE
LAKES. EARLY SUN AND MON MORNING WILL BE CHILLY WITH LIGHT WINDS
NEAR THE SFC RIDGE AXIS ALLOWING TEMPS TO DIP INTO THE 30S AND
POSSIBLY EVEN THE 20S AT SOME OF THE TRADITIONAL INTERIOR COLD
SPOTS.
MON NIGHT THRU WED...MEDIUM RANGE MODELS SHOW SHORTWAVE RIDING OVER
MID/UPPER RIDGE CENTERED IN THE MISSISSIPPI RIVER VALLEY. TIMING OF
FEATURE AND HOW QUICKLY PCPN SPREADS INTO DRY AIR MASS EMANATING
FROM HIGH PRES RIDGE EXTENDING S FROM HUDSON BAY STILL NEED TO BE
WORKED OUT. FOR NOW...WILL CARRY MODEL CONSENSUS CHC POPS GRADUALLY
SPREADING E TO REFLECT THE PCPN POTENTIAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 130 AM EDT THU MAY 15 2014
WINDS WILL INCREASE AFTER 09Z TONIGHT /GUSTS NEARING 25KTS OUT OF
THE N AT SAW BY LATE MORNING/ IN RESPONSE TO THE INCREASING PRESSURE
GRADIENT BETWEEN A STRONG HIGH PRESSURE SYSTEM ACROSS THE
DAKOTAS/MN/ONTARIO...AND A LOW SLIDING FROM INDIANA AT DAYBREAK TO E
LOWER MI AND GREATER LAKE HURON BY 18Z THURSDAY. WITH THE ASSISTANCE
OF UPSLOPE N WINDS...SAW COULD GET SOME RAIN AND SNOW BY 19Z
THURSDAY. VFR CONDITIONS EXPECTED TO CONTINUE AT CMX AND IWD THIS
PERIOD WHILE RAIN AND SNOW AND MVFR CONDITIONS THAT MOVE INTO SAW BY
EARLY THU AFTERNOON REMAINING INTO THU EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 AM EDT THU MAY 15 2014
LOW PRES WILL LIFT FROM NE INDIANA ACROSS LAKE HURON TODAY AND THEN
TO NEAR JAMES BAY BY FRI EVENING. AS A RESULT...EXPECT WINDS TO
INCREASE TO 20-25KT OVER THE E HALF OF LAKE SUPERIOR TODAY/TONIGHT.
WINDS WILL BE LIGHTER OVER THE W. WINDS WILL DIMINISH FRIDAY AS THE
LOW MOVES FARTHER AWAY. FRI NIGHT THRU THE WEEKEND...WINDS WILL BE
UNDER 20KT AND EVEN UNDER 10KT AT TIMES UNDER WEAKER PRES GRADIENT.
LOW PRES DEVELOPING OVER THE PLAINS EARLY NEXT WEEK WILL BRING SOME
INCREASE IN E TO SE WINDS. AS IS NORMALLY THE CASE IN THIS TYPE OF
PATTERN...WILL NEED TO WATCH FOR STRONGER WINDS TO DEVELOP OVER THE
WRN PART OF THE LAKE DUE TO COASTAL CONVERGENCE/FUNNELING.
&&
.HYDROLOGY...
ISSUED AT 531 AM EDT THU MAY 15 2014
THE MAIN RIVERS OF CONCERN CONTINUE TO BE OVER THE W HALF OF UPPER
MI. NO FLOOD WARNINGS ARE IN EFFECT. ONLY FLOOD ADVYS REMAIN FOR
STURGEON RIVER AT CHASSELL AND FOR THE MICHIGAMME RIVER AT WITCH
LAKE...REPUBLIC AND CRYSTAL FALLS.
FORTUNATELY...PCPN EXPECTED OVER THE NEXT FEW DAYS...OCCURRING
MOSTLY TODAY THRU FRI MORNING...WILL BE ON THE LIGHTER SIDE SO THAT
RIVERS SHOULD HAVE LITTLE OR NO RESPONSE. AS A RESULT...AN OVERALL
SLOW DOWNWARD TREND SHOULD BE THE RULE ON ALL RIVERS/STREAMS OVER
THE NEXT FEW DAYS. DRY WEATHER EARLY NEXT WEEK SHOULD FURTHER AID
THE DECLINE OF RIVER LEVELS.
THOSE LIVING NEAR RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO
MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...07
MARINE...ROLFSON
HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
600 PM EDT THU MAY 15 2014
.SYNOPSIS...
A COLD FRONT WILL MARCH VERY SLOWLY EAST ACROSS THE AREA LATE
TONIGHT THROUGH FRIDAY ACCOMPANIED BY A WIDESPREAD SOAKING RAIN
AND PERHAPS A FEW RUMBLES OF THUNDER. THE RAIN COULD BE HEAVY AT
TIMES. BEHIND THE FRONT...COOLER WEATHER IS IN STORE FOR THE
WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
5 PM UPDATE...
SHOWERS AND A TSTORM HAVE DEVELOPED IN NE PA AND CATSKILLS. ADDED
POPS AND WX THERE AND EXTENDED IT NORTH INTO SRN TIER THIS
EVENING. INCREASED CLOUD COVER TO CLOUDY OR MOSTLY CLOUDY.
310 PM UPDATE...
LGT SHOWERS HV SPREAD INTO WRN NY IN AREA OF DEEP SRLY AND
ANONYMOUSLY MOIST FLOW COMING STRAIGHT OFF THE GOM. H5 LOW SPINNING
THRU IOWA WITH SFC RIDGE AXIS NOSING UP INTO THE CANADIAN MARITIMES.
CWA IS SQUASHED IN BTWN THESE TWO SYSTEMS WITH A STEADY FEED OF
MOISTURE FCST TO INCREASE DRG THE OVRNGT HRS.
CDFNT HAS MADE ITS WAY INTO ERN OH AND WITH FLOW FM THE SFC TO UPR
HEIGHTS PROGGED TO BE STRONG OUT OF THE SOUTH, EXPECT FRONT TO
PROPAGATE VRY SLOWLY ACRS THE CWA DRG THE OVRNGT AND INTO THE
DAYTIME TOMORROW.
EVIDENCE OF THIS IS SHOWERS ARE CURRENTLY GETTING INTO ALLEGANY
COUNTY AND LATEST HRRR DOES NOT BRING ANY PCPN INTO WRN STEUBEN
UNTIL CLOSE TO 21Z THIS AFTN. MAIN BRUNT OF SHOWERS DO NOT GET INTO
THE FINGER LKS UNTIL AFT 02Z TONIGHT. ALL MODELS ARE INDICATING A
VRY THIN RIBBON OF INSTABILITY AND WEAK MID-LVL LAPSE RATES
IMMEDIATELY AHD OF FRONTAL BNDRY. HV TRIED TO INDICATE THIN AREA OF
EMBEDDED THUNDER IN THE GRIDS TO COINCIDE WITH FROPA.
WL JUST MENTION LIGHT RAIN IN GRIDS UNTIL 06Z THEN A MENTION OF
MODERATE RAIN AND A CHC FOR HVY RAIN THEREAFTER AS UPPER LVL JET
STREAK SETS UP SHOP ACRS THE GREAT LKS WITH REGION IN RIGHT ENTRANCE
REGION. CURRENT THINKING IS THE HEAVIEST RAIN LOOKS TO FALL AFT 06Z
ACRS THE FINGER LKS AND THEN VRY SLOWLY APPCH THE I-81 CORRIDOR BTWN
12Z-15Z. MOST OF THE HVY RAIN WL FALL BHND THE FRONT WITH THUNDER
JUST OUT AHD OF BNDRY.
FOR THIS REASON HV EXTENDED THE FLASH FLOOD WATCH OVR THE ENTIRE CWA
WITH AREAS WEST OF I-81 VALID FM 03Z FRI - 00Z SAT AND EAST OF I-81
FROM 06Z FRI- 06Z SAT. SRLY H8 JET OF 50-60KTS KICKS IN AFT 00Z
TONIGHT WHICH IS A GOOD 4-5 STANDARD DEVIATIONS ABV NORMAL. THIS
COUPLED WITH PW VALUES OF 2-3 SD LEADS TO A POTENTIAL HVY RAIN EVENT
FOR THE ENTIRE CWA THRU THE DAY ON FRIDAY.
36-HR STORM TOTAL AMNTS LOOK TO RANGE FM 1.5-2.5 INCHES WITH LOCALLY
HIGHER AMNTS POSSIBLE IN ANY CONVECTION THAT CAN DVLP OVRNGT. IF
THESE AMNTS FALL IN LESS THAN A 6-HR PERIOD OF TIME THIS MAY CAUSE
FLASH FLOODING, HWVR IF THEY FALL OVR A 12-HR PERIOD OF TIME THESE
AMNTS MAY CAUSE JUST NUISANCE FLOODING. GIVEN THE UNCERTAINTY THAT
EXISTS FEEL IT PRUDENT TO ISSUE A FLASH FLOOD WATCH FOR ALL OF CNTRL
NY AND NEPA.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
310 PM UPDATE...
MODERATE TO HVY RAIN WL CONTINUE INTO A PORTION OF THE AFTN BUT RAIN
WL BEGIN TO TAPER OFF FM WEST TO EAST AFT 21Z AS AREA LOSES UPR LVL
DIVERGENCE AS UPR LVL JET SHIFTS EAST. HVY STRATIFORM RAIN WL OCCUR
THRU MOST OF THE DAY WITH TEMPS ACRS THE NWRN ZONES RMNG FAIRLY
STEADY IN THE M/U 50S WITH THE CNTRL SRN TIER FALLING DRG THE DAY
WITH HIGHS COMING MID-MRNG.
UPR LVL LOW WL PERSIST BACK TO THE WEST THRU THE END OF THE SHORT
TERM WITH TEMPS NEAR TO SLIGHTLY BELOW NORMAL VALUES. SAT NGT LOWS
WL BE APPCHG FROST ADVISORY CRITERIA AND MAY NEED TO CONSIDER
HEADLINES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
200 PM UPDATE...UPPER LEVEL TROF AXIS WILL BE IN THE PROCESS OF
MOVING EAST AND CUTTING OFF OVER THE ATLANTIC OCEAN SUNDAY NIGHT.
WHILE THE BEST SHOT FOR SHOWERS WILL BE EAST OF THE FORECAST AREA,
WE WILL BE CLOSE ENOUGH TO WARRANT A LOW CHANCE FOR SHOWERS
THROUGH MONDAY NIGHT ESPECIALLY EAST OF I-81. OUR AREA WILL BE IN
A RIDGE OF HIGH PRESSURE WILL NICE WEATHER TUESDAY AND WEDNESDAY
BEFORE THE DEVELOPING NORTHWEST FLOW SENDS ANOTHER UPPER LEVEL LOW
OUR WAY. TEMPS WILL BE NEAR NORMAL, OR UPPER 60S TO NEAR 70 DURING
THE PERIOD.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
MAINLY VFR THIS AFTERNOON WITH THE EXCEPTION OF KAVP WHERE MVFR
CIGS ARE POSSIBLE NOW AND THEN, THROUGH AT LEAST 21Z. MUCH LIKE
LAST NIGHT, A BRISK SOUTH TO SOUTHEAST FLOW WILL PULL LOW CLOUDS
CURRENTLY OVER EASTERN PA QUICKLY OVER THE SOUTHERN TERMINALS THIS
EVENING. EXPECT A RETURN TO MVFR CIGS, RANGING FROM 1500 FEET ON
THE HILLTOPS TO 2500 FEET IN THE VALLEYS BETWEEN 0Z AND 02Z. UP
NORTH A MUCH SLOWER ARRIVAL, CLOSER TO 08Z OR THEREAFTER.
A COLD FRONT WILL BRING RAIN SHOWERS TO THE TERMINALS PRIOR TO
DAYBREAK FRIDAY. MVFR CIGS IN PLACE WILL LOW TO LOW END MVFR.
WHILE IFR CAN`T BE RULED OUT, THESE CIGS ARE NOT LIKELY UNTIL
AFTER THE FRONTAL PASSAGE. MODEL GUIDANCE DIFFERS BY A LEAST A FEW
HOURS ON THIS PASSAGE, THUS WENT IN THE MIDDLE FOR NOW. THIS WOULD
BRING IFR CIGS INTO THE ELM/KSYR/KITH AREA AROUND 12Z. WITH A VERY
SLOW MOVEMENT TO THE FRONT IFR CIGS ARE NOT EXPECTED UNTIL AFTER
THE END OF THE TAF PERIOD AT THE REST OF THE TERMINALS, OR ROUGHLY
TOWARD 21Z TO 23Z.
OUTLOOK...
FRI NGT...RESTRICTIONS IN SHRA AS COLD FRONT SLOWLY TRUDGES
THROUGH REGION.
SAT...MVFR RESTRICTIONS POSSIBLE EARLY, BECOMING VFR DURING THE
AFTERNOON.
SUN/MON...MVFR RESTRICTIONS POSSIBLE IN ISOLATED SHOWERS BUT MAINLY
VFR.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLASH FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY
NIGHT FOR PAZ039-040-043-044-047-048-072.
FLASH FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH FRIDAY
EVENING FOR PAZ038.
NY...FLASH FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY
NIGHT FOR NYZ009-018-036-037-044>046-056-057-062.
FLASH FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH FRIDAY
EVENING FOR NYZ015>017-022>025-055.
&&
$$
SYNOPSIS...PVN/TAC
NEAR TERM...PVN/TAC
SHORT TERM...CMG/PVN
LONG TERM...HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
313 PM EDT THU MAY 15 2014
.SYNOPSIS...
A COLD FRONT WILL MARCH VERY SLOWLY EAST ACROSS THE AREA LATE
TONIGHT THROUGH FRIDAY ACCOMPANIED BY A WIDESPREAD SOAKING RAIN AND
PERHAPS A FEW RUMBLES OF THUNDER. THE RAIN COULD BE HEAVY AT
TIMES. BEHIND THE FRONT...COOLER WEATHER IS IN STORE FOR THE
WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
310 PM UPDATE...
LGT SHOWERS HV SPREAD INTO WRN NY IN AREA OF DEEP SRLY AND
ANONYMOUSLY MOIST FLOW COMING STRAIGHT OFF THE GOM. H5 LOW SPINNING
THRU IOWA WITH SFC RIDGE AXIS NOSING UP INTO THE CANADIAN MARITIMES.
CWA IS SQUASHED IN BTWN THESE TWO SYSTEMS WITH A STEADY FEED OF
MOISTURE FCST TO INCREASE DRG THE OVRNGT HRS.
CDFNT HAS MADE ITS WAY INTO ERN OH AND WITH FLOW FM THE SFC TO UPR
HEIGHTS PROGGED TO BE STRONG OUT OF THE SOUTH, EXPECT FRONT TO
PROPAGATE VRY SLOWLY ACRS THE CWA DRG THE OVRNGT AND INTO THE
DAYTIME TOMORROW.
EVIDENCE OF THIS IS SHOWERS ARE CURRENTLY GETTING INTO ALLEGANY
COUNTY AND LATEST HRRR DOES NOT BRING ANY PCPN INTO WRN STEUBEN
UNTIL CLOSE TO 21Z THIS AFTN. MAIN BRUNT OF SHOWERS DO NOT GET INTO
THE FINGER LKS UNTIL AFT 02Z TONIGHT. ALL MODELS ARE INDICATING A
VRY THIN RIBBON OF INSTABILITY AND WEAK MID-LVL LAPSE RATES
IMMEDIATELY AHD OF FRONTAL BNDRY. HV TRIED TO INDICATE THIN AREA OF
EMBEDDED THUNDER IN THE GRIDS TO COINCIDE WITH FROPA.
WL JUST MENTION LIGHT RAIN IN GRIDS UNTIL 06Z THEN A MENTION OF
MODERATE RAIN AND A CHC FOR HVY RAIN THEREAFTER AS UPPER LVL JET
STREAK SETS UP SHOP ACRS THE GREAT LKS WITH REGION IN RIGHT ENTRANCE
REGION. CURRENT THINKING IS THE HEAVIEST RAIN LOOKS TO FALL AFT 06Z
ACRS THE FINGER LKS AND THEN VRY SLOWLY APPCH THE I-81 CORRIDOR BTWN
12Z-15Z. MOST OF THE HVY RAIN WL FALL BHND THE FRONT WITH THUNDER
JUST OUT AHD OF BNDRY.
FOR THIS REASON HV EXTENDED THE FLASH FLOOD WATCH OVR THE ENTIRE CWA
WITH AREAS WEST OF I-81 VALID FM 03Z FRI - 00Z SAT AND EAST OF I-81
FROM 06Z FRI- 06Z SAT. SRLY H8 JET OF 50-60KTS KICKS IN AFT 00Z
TONIGHT WHICH IS A GOOD 4-5 STANDARD DEVIATIONS ABV NORMAL. THIS
COUPLED WITH PW VALUES OF 2-3 SD LEADS TO A POTENTIAL HVY RAIN EVENT
FOR THE ENTIRE CWA THRU THE DAY ON FRIDAY.
36-HR STORM TOTAL AMNTS LOOK TO RANGE FM 1.5-2.5 INCHES WITH LOCALLY
HIGHER AMNTS POSSIBLE IN ANY CONVECTION THAT CAN DVLP OVRNGT. IF
THESE AMNTS FALL IN LESS THAN A 6-HR PERIOD OF TIME THIS MAY CAUSE
FLASH FLOODING, HWVR IF THEY FALL OVR A 12-HR PERIOD OF TIME THESE
AMNTS MAY CAUSE JUST NUISANCE FLOODING. GIVEN THE UNCERTAINTY THAT
EXISTS FEEL IT PRUDENT TO ISSUE A FLASH FLOOD WATCH FOR ALL OF CNTRL
NY AND NEPA.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
310 PM UPDATE...
MODERATE TO HVY RAIN WL CONTINUE INTO A PORTION OF THE AFTN BUT RAIN
WL BEGIN TO TAPER OFF FM WEST TO EAST AFT 21Z AS AREA LOSES UPR LVL
DIVERGENCE AS UPR LVL JET SHIFTS EAST. HVY STRATIFORM RAIN WL OCCUR
THRU MOST OF THE DAY WITH TEMPS ACRS THE NWRN ZONES RMNG FAIRLY
STEADY IN THE M/U 50S WITH THE CNTRL SRN TIER FALLING DRG THE DAY
WITH HIGHS COMING MID-MRNG.
UPR LVL LOW WL PERSIST BACK TO THE WEST THRU THE END OF THE SHORT
TERM WITH TEMPS NEAR TO SLIGHTLY BELOW NORMAL VALUES. SAT NGT LOWS
WL BE APPCHG FROST ADVISORY CRITERIA AND MAY NEED TO CONSIDER
HEADLINES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
200 PM UPDATE...UPPER LEVEL TROF AXIS WILL BE IN THE PROCESS OF
MOVING EAST AND CUTTING OFF OVER THE ATLANTIC OCEAN SUNDAY NIGHT.
WHILE THE BEST SHOT FOR SHOWERS WILL BE EAST OF THE FORECAST AREA,
WE WILL BE CLOSE ENOUGH TO WARRANT A LOW CHANCE FOR SHOWERS
THROUGH MONDAY NIGHT ESPECIALLY EAST OF I-81. OUR AREA WILL BE IN
A RIDGE OF HIGH PRESSURE WILL NICE WEATHER TUESDAY AND WEDNESDAY
BEFORE THE DEVELOPING NORTHWEST FLOW SENDS ANOTHER UPPER LEVEL LOW
OUR WAY. TEMPS WILL BE NEAR NORMAL, OR UPPER 60S TO NEAR 70 DURING
THE PERIOD.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
MAINLY VFR THIS AFTERNOON WITH THE EXCEPTION OF KAVP WHERE MVFR
CIGS ARE POSSIBLE NOW AND THEN, THROUGH AT LEAST 21Z. MUCH LIKE
LAST NIGHT, A BRISK SOUTH TO SOUTHEAST FLOW WILL PULL LOW CLOUDS
CURRENTLY OVER EASTERN PA QUICKLY OVER THE SOUTHERN TERMINALS THIS
EVENING. EXPECT A RETURN TO MVFR CIGS, RANGING FROM 1500 FEET ON
THE HILLTOPS TO 2500 FEET IN THE VALLEYS BETWEEN 0Z AND 02Z. UP
NORTH A MUCH SLOWER ARRIVAL, CLOSER TO 08Z OR THEREAFTER.
A COLD FRONT WILL BRING RAIN SHOWERS TO THE TERMINALS PRIOR TO
DAYBREAK FRIDAY. MVFR CIGS IN PLACE WILL LOW TO LOW END MVFR.
WHILE IFR CAN`T BE RULED OUT, THESE CIGS ARE NOT LIKELY UNTIL
AFTER THE FRONTAL PASSAGE. MODEL GUIDANCE DIFFERS BY A LEAST A FEW
HOURS ON THIS PASSAGE, THUS WENT IN THE MIDDLE FOR NOW. THIS WOULD
BRING IFR CIGS INTO THE ELM/KSYR/KITH AREA AROUND 12Z. WITH A VERY
SLOW MOVEMENT TO THE FRONT IFR CIGS ARE NOT EXPECTED UNTIL AFTER
THE END OF THE TAF PERIOD AT THE REST OF THE TERMINALS, OR ROUGHLY
TOWARD 21Z TO 23Z.
OUTLOOK...
FRI NGT...RESTRICTIONS IN SHRA AS COLD FRONT SLOWLY TRUDGES
THROUGH REGION.
SAT...MVFR RESTRICTIONS POSSIBLE EARLY, BECOMING VFR DURING THE
AFTERNOON.
SUN/MON...MVFR RESTRICTIONS POSSIBLE IN ISOLATED SHOWERS BUT MAINLY
VFR.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...FLASH FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY
NIGHT FOR PAZ039-040-043-044-047-048-072.
FLASH FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH FRIDAY
EVENING FOR PAZ038.
NY...FLASH FLOOD WATCH FROM 2 AM EDT FRIDAY THROUGH LATE FRIDAY
NIGHT FOR NYZ009-018-036-037-044>046-056-057-062.
FLASH FLOOD WATCH FROM 11 PM EDT THIS EVENING THROUGH FRIDAY
EVENING FOR NYZ015>017-022>025-055.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...CMG/PVN
LONG TERM...HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
117 PM CDT THU MAY 15 2014
.UPDATE...
ISSUED AT 115 PM CDT THU MAY 15 2014
NO CHANGES PLANNED FOR THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
THE MAIN CHALLENGE WILL BE FREEZE POTENTIAL DURING THE OVERNIGHT
PERIODS. 00Z MODELS IN DECENT AGREEMENT.
SURFACE RIDGING IS CURRENTLY (08Z) POSITIONED ACROSS NORTH
DAKOTA...SLOWLY PROPAGATING TO THE EAST. CLOUDS REMAIN ALONG AND
EAST OF THE VALLEY. TEMPERATURES ARE IN THE UPPER 20S/LOW 30S
WHERE THE SKY IS CLEAR...AND IN THE MID 30S WHERE CLOUDS REMAIN.
THE LATEST RAP GUIDANCE INDICATES THESE CLOUDS WILL REMAIN AS IS
THROUGH THE REMAINDER OF THE NIGHT. WILL NEED TO CANCEL PART OF
THE FREEZE WARNING FOR THIS MORNING GIVEN THE LACK OF CLEARING
FROM THE WEST...ALTHOUGH WILL TAKE INTO ACCOUNT THE POSSIBILITY
FOR SOME CLEARING FROM THE WEST...AND ONLY CANCEL A PORTION OF
WEST CENTRAL MINNESOTA (FOR NOW).
TODAY...SINCE THE SFC HIGH SEEMS TO BE BUILDING IN A BIT SLOWER
THAN ANTICIPATED...WITH INCREASE SKY COVER...AND LOWER MAX TEMPS A
BIT. OTHERWISE...STILL ANTICIPATE CLEARING BY MID-LATE AFTERNOON
AS THE SFC HIGH OVERTAKES THE REGION.
TONIGHT...THE SFC HIGH WILL BE OVERHEAD THE ENTIRE NIGHT...AND
CLEAR SKY APPEARS VERY LIKELY. LOWERED THE MIN TEMPS TO VALUES
SIMILAR TO WHAT WE ARE EXPERIENCING CURRENTLY. ANTICIPATE ANOTHER
FREEZE WARNING BEING ISSUED BY THE DAY SHIFT.
FRIDAY..HIGH PRESSURE WILL LEAD TO MINIMAL MIXING...BUT AS THE
UPPER TROUGH GRADUALLY SHIFTS EAST CONVECTIVE TEMPS WILL BE
SLIGHTLY WARMER...LEADING TO LESS CU DEVELOPMENT AND SLIGHTLY
WARMER MAX TEMPS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
FRIDAY NIGHT-SATURDAY NIGHT...ONE LAST NIGHT WITH NEAR FREEZING
TEMPERATURES FRIDAY NIGHT...ALTHOUGH VALUES SHOULD BE SLIGHTLY
WARMER THAN PREVIOUS NIGHTS. WEAK RETURN FLOW DEVELOPS
SATURDAY/SATURDAY NIGHT AS THE NEXT UPPER WAVE CRASHES THE PAC NW.
UPPER RIDGING WILL KEEP THE WX DRY...WITH TEMPERATURES APPROACHING
60F ON SATURDAY...AND REMAINING IN THE UPPER 30S/LOW 40S SATURDAY
NIGHT.
SUNDAY-WEDNESDAY... HIGH AMPLITUDE LONG WAVE PATTERN BECOMES MORE
ZONAL THIS PERIOD. FLOW ALOFT BECOMES MORE SPLIT DURING THIS PERIOD.
THE ECMWF WAS A FASTER SOLUTION THAN THE GFS. WILL PREFER A BLEND OF
THE GFS AND ECMWF.
LITTLE CHANGE TO TEMPS DURING THE PERIOD. A LITTLE WARMER FOR TUE
AND WED COMPARED TO YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 115 PM CDT THU MAY 15 2014
CLOUDS WILL BE THE MAIN AVIATION CHALLENGE WITH AN EXTENSIVE CUMULUS
FIELD OUT THERE AGAIN. BY LATE AFTERNOON OR EARLY EVENING WITH LOSS
OF HEATING THINK MOST OF THE CUMULUS SHOULD FADE AWAY. AFTER THAT
LOOKING FOR CLEAR SKIES AND LIGHT WINDS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1109 AM CDT THU MAY 15 2014
.UPDATE...
ISSUED AT 1105 AM CDT THU MAY 15 2014
CLOUDS CONTINUE TO REMAIN ACROSS THE SOUTH AND EAST...AND CUMULUS
IS DEVELOPING ON THE NORTHERN EDGE WITH LOW CONVECTIVE TEMPS IN
THE LOW/MID 40S.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
THE MAIN CHALLENGE WILL BE FREEZE POTENTIAL DURING THE OVERNIGHT
PERIODS. 00Z MODELS IN DECENT AGREEMENT.
SURFACE RIDGING IS CURRENTLY (08Z) POSITIONED ACROSS NORTH
DAKOTA...SLOWLY PROPAGATING TO THE EAST. CLOUDS REMAIN ALONG AND
EAST OF THE VALLEY. TEMPERATURES ARE IN THE UPPER 20S/LOW 30S
WHERE THE SKY IS CLEAR...AND IN THE MID 30S WHERE CLOUDS REMAIN.
THE LATEST RAP GUIDANCE INDICATES THESE CLOUDS WILL REMAIN AS IS
THROUGH THE REMAINDER OF THE NIGHT. WILL NEED TO CANCEL PART OF
THE FREEZE WARNING FOR THIS MORNING GIVEN THE LACK OF CLEARING
FROM THE WEST...ALTHOUGH WILL TAKE INTO ACCOUNT THE POSSIBILITY
FOR SOME CLEARING FROM THE WEST...AND ONLY CANCEL A PORTION OF
WEST CENTRAL MINNESOTA (FOR NOW).
TODAY...SINCE THE SFC HIGH SEEMS TO BE BUILDING IN A BIT SLOWER
THAN ANTICIPATED...WITH INCREASE SKY COVER...AND LOWER MAX TEMPS A
BIT. OTHERWISE...STILL ANTICIPATE CLEARING BY MID-LATE AFTERNOON
AS THE SFC HIGH OVERTAKES THE REGION.
TONIGHT...THE SFC HIGH WILL BE OVERHEAD THE ENTIRE NIGHT...AND
CLEAR SKY APPEARS VERY LIKELY. LOWERED THE MIN TEMPS TO VALUES
SIMILAR TO WHAT WE ARE EXPERIENCING CURRENTLY. ANTICIPATE ANOTHER
FREEZE WARNING BEING ISSUED BY THE DAY SHIFT.
FRIDAY..HIGH PRESSURE WILL LEAD TO MINIMAL MIXING...BUT AS THE
UPPER TROUGH GRADUALLY SHIFTS EAST CONVECTIVE TEMPS WILL BE
SLIGHTLY WARMER...LEADING TO LESS CU DEVELOPMENT AND SLIGHTLY
WARMER MAX TEMPS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
FRIDAY NIGHT-SATURDAY NIGHT...ONE LAST NIGHT WITH NEAR FREEZING
TEMPERATURES FRIDAY NIGHT...ALTHOUGH VALUES SHOULD BE SLIGHTLY
WARMER THAN PREVIOUS NIGHTS. WEAK RETURN FLOW DEVELOPS
SATURDAY/SATURDAY NIGHT AS THE NEXT UPPER WAVE CRASHES THE PAC NW.
UPPER RIDGING WILL KEEP THE WX DRY...WITH TEMPERATURES APPROACHING
60F ON SATURDAY...AND REMAINING IN THE UPPER 30S/LOW 40S SATURDAY
NIGHT.
SUNDAY-WEDNESDAY... HIGH AMPLITUDE LONG WAVE PATTERN BECOMES MORE
ZONAL THIS PERIOD. FLOW ALOFT BECOMES MORE SPLIT DURING THIS PERIOD.
THE ECMWF WAS A FASTER SOLUTION THAN THE GFS. WILL PREFER A BLEND OF
THE GFS AND ECMWF.
LITTLE CHANGE TO TEMPS DURING THE PERIOD. A LITTLE WARMER FOR TUE
AND WED COMPARED TO YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 626 AM CDT THU MAY 15 2014
VFR CIGS (ALONG AND EAST OF THE RED RIVER VALLEY) WILL GRADUALLY
DISSIPATE AND/OR MOVE EASTWARD TODAY...WITH CLEAR SKY TONIGHT.
WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
830 AM CDT THU MAY 15 2014
.UPDATE...
ISSUED AT 830 AM CDT THU MAY 15 2014
THE FREEZE WARNING HAS BEEN CANCELLED SINCE TEMPS HAVE RISEN ABOVE
FREEZING. OTHERWISE...THE REST OF THE FORECAST IS IN GOOD SHAPE
FOR THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
THE MAIN CHALLENGE WILL BE FREEZE POTENTIAL DURING THE OVERNIGHT
PERIODS. 00Z MODELS IN DECENT AGREEMENT.
SURFACE RIDGING IS CURRENTLY (08Z) POSITIONED ACROSS NORTH
DAKOTA...SLOWLY PROPAGATING TO THE EAST. CLOUDS REMAIN ALONG AND
EAST OF THE VALLEY. TEMPERATURES ARE IN THE UPPER 20S/LOW 30S
WHERE THE SKY IS CLEAR...AND IN THE MID 30S WHERE CLOUDS REMAIN.
THE LATEST RAP GUIDANCE INDICATES THESE CLOUDS WILL REMAIN AS IS
THROUGH THE REMAINDER OF THE NIGHT. WILL NEED TO CANCEL PART OF
THE FREEZE WARNING FOR THIS MORNING GIVEN THE LACK OF CLEARING
FROM THE WEST...ALTHOUGH WILL TAKE INTO ACCOUNT THE POSSIBILITY
FOR SOME CLEARING FROM THE WEST...AND ONLY CANCEL A PORTION OF
WEST CENTRAL MINNESOTA (FOR NOW).
TODAY...SINCE THE SFC HIGH SEEMS TO BE BUILDING IN A BIT SLOWER
THAN ANTICIPATED...WITH INCREASE SKY COVER...AND LOWER MAX TEMPS A
BIT. OTHERWISE...STILL ANTICIPATE CLEARING BY MID-LATE AFTERNOON
AS THE SFC HIGH OVERTAKES THE REGION.
TONIGHT...THE SFC HIGH WILL BE OVERHEAD THE ENTIRE NIGHT...AND
CLEAR SKY APPEARS VERY LIKELY. LOWERED THE MIN TEMPS TO VALUES
SIMILAR TO WHAT WE ARE EXPERIENCING CURRENTLY. ANTICIPATE ANOTHER
FREEZE WARNING BEING ISSUED BY THE DAY SHIFT.
FRIDAY..HIGH PRESSURE WILL LEAD TO MINIMAL MIXING...BUT AS THE
UPPER TROUGH GRADUALLY SHIFTS EAST CONVECTIVE TEMPS WILL BE
SLIGHTLY WARMER...LEADING TO LESS CU DEVELOPMENT AND SLIGHTLY
WARMER MAX TEMPS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
FRIDAY NIGHT-SATURDAY NIGHT...ONE LAST NIGHT WITH NEAR FREEZING
TEMPERATURES FRIDAY NIGHT...ALTHOUGH VALUES SHOULD BE SLIGHTLY
WARMER THAN PREVIOUS NIGHTS. WEAK RETURN FLOW DEVELOPS
SATURDAY/SATURDAY NIGHT AS THE NEXT UPPER WAVE CRASHES THE PAC NW.
UPPER RIDGING WILL KEEP THE WX DRY...WITH TEMPERATURES APPROACHING
60F ON SATURDAY...AND REMAINING IN THE UPPER 30S/LOW 40S SATURDAY
NIGHT.
SUNDAY-WEDNESDAY... HIGH AMPLITUDE LONG WAVE PATTERN BECOMES MORE
ZONAL THIS PERIOD. FLOW ALOFT BECOMES MORE SPLIT DURING THIS PERIOD.
THE ECMWF WAS A FASTER SOLUTION THAN THE GFS. WILL PREFER A BLEND OF
THE GFS AND ECMWF.
LITTLE CHANGE TO TEMPS DURING THE PERIOD. A LITTLE WARMER FOR TUE
AND WED COMPARED TO YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 626 AM CDT THU MAY 15 2014
VFR CIGS (ALONG AND EAST OF THE RED RIVER VALLEY) WILL GRADUALLY
DISSIPATE AND/OR MOVE EASTWARD TODAY...WITH CLEAR SKY TONIGHT.
WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
626 AM CDT THU MAY 15 2014
.UPDATE...
ISSUED AT 626 AM CDT THU MAY 15 2014
THE CLOUDS HAVE NOT MOVED...AND HAVE ACTUALLY MOVED BACK WEST A
BIT. AT ANY RATE...WILL CANCEL THE FREEZE WARNING FOR AREAS THAT
ARE CURRENTLY (11Z) ABOVE FREEZING (WE ARE AFTER SUNRISE AND TEMPS
WILL NOW BEGIN TO RISE). AREAS UNDER CLEAR SKY WILL REMAIN BELOW
FREEZING FOR ANOTHER HOUR OR TWO AND WILL LEAVE HEADLINES AS IS
HERE. THE REMAINDER OF THE FORECAST IS IN GOOD SHAPE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
THE MAIN CHALLENGE WILL BE FREEZE POTENTIAL DURING THE OVERNIGHT
PERIODS. 00Z MODELS IN DECENT AGREEMENT.
SURFACE RIDGING IS CURRENTLY (08Z) POSITIONED ACROSS NORTH
DAKOTA...SLOWLY PROPAGATING TO THE EAST. CLOUDS REMAIN ALONG AND
EAST OF THE VALLEY. TEMPERATURES ARE IN THE UPPER 20S/LOW 30S
WHERE THE SKY IS CLEAR...AND IN THE MID 30S WHERE CLOUDS REMAIN.
THE LATEST RAP GUIDANCE INDICATES THESE CLOUDS WILL REMAIN AS IS
THROUGH THE REMAINDER OF THE NIGHT. WILL NEED TO CANCEL PART OF
THE FREEZE WARNING FOR THIS MORNING GIVEN THE LACK OF CLEARING
FROM THE WEST...ALTHOUGH WILL TAKE INTO ACCOUNT THE POSSIBILITY
FOR SOME CLEARING FROM THE WEST...AND ONLY CANCEL A PORTION OF
WEST CENTRAL MINNESOTA (FOR NOW).
TODAY...SINCE THE SFC HIGH SEEMS TO BE BUILDING IN A BIT SLOWER
THAN ANTICIPATED...WITH INCREASE SKY COVER...AND LOWER MAX TEMPS A
BIT. OTHERWISE...STILL ANTICIPATE CLEARING BY MID-LATE AFTERNOON
AS THE SFC HIGH OVERTAKES THE REGION.
TONIGHT...THE SFC HIGH WILL BE OVERHEAD THE ENTIRE NIGHT...AND
CLEAR SKY APPEARS VERY LIKELY. LOWERED THE MIN TEMPS TO VALUES
SIMILAR TO WHAT WE ARE EXPERIENCING CURRENTLY. ANTICIPATE ANOTHER
FREEZE WARNING BEING ISSUED BY THE DAY SHIFT.
FRIDAY..HIGH PRESSURE WILL LEAD TO MINIMAL MIXING...BUT AS THE
UPPER TROUGH GRADUALLY SHIFTS EAST CONVECTIVE TEMPS WILL BE
SLIGHTLY WARMER...LEADING TO LESS CU DEVELOPMENT AND SLIGHTLY
WARMER MAX TEMPS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
FRIDAY NIGHT-SATURDAY NIGHT...ONE LAST NIGHT WITH NEAR FREEZING
TEMPERATURES FRIDAY NIGHT...ALTHOUGH VALUES SHOULD BE SLIGHTLY
WARMER THAN PREVIOUS NIGHTS. WEAK RETURN FLOW DEVELOPS
SATURDAY/SATURDAY NIGHT AS THE NEXT UPPER WAVE CRASHES THE PAC NW.
UPPER RIDGING WILL KEEP THE WX DRY...WITH TEMPERATURES APPROACHING
60F ON SATURDAY...AND REMAINING IN THE UPPER 30S/LOW 40S SATURDAY
NIGHT.
SUNDAY-WEDNESDAY... HIGH AMPLITUDE LONG WAVE PATTERN BECOMES MORE
ZONAL THIS PERIOD. FLOW ALOFT BECOMES MORE SPLIT DURING THIS PERIOD.
THE ECMWF WAS A FASTER SOLUTION THAN THE GFS. WILL PREFER A BLEND OF
THE GFS AND ECMWF.
LITTLE CHANGE TO TEMPS DURING THE PERIOD. A LITTLE WARMER FOR TUE
AND WED COMPARED TO YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 626 AM CDT THU MAY 15 2014
VFR CIGS (ALONG AND EAST OF THE RED RIVER VALLEY) WILL GRADUALLY
DISSIPATE AND/OR MOVE EASTWARD TODAY...WITH CLEAR SKY TONIGHT.
WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR NDZ006>008-
014>016-024-026>030-038-039-049-052-054.
MN...FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR MNZ001-004-005-
007.
&&
$$
UPDATE...TG
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
350 AM CDT THU MAY 15 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
THE MAIN CHALLENGE WILL BE FREEZE POTENTIAL DURING THE OVERNIGHT
PERIODS. 00Z MODELS IN DECENT AGREEMENT.
SURFACE RIDGING IS CURRENTLY (08Z) POSITIONED ACROSS NORTH
DAKOTA...SLOWLY PROPAGATING TO THE EAST. CLOUDS REMAIN ALONG AND
EAST OF THE VALLEY. TEMPERATURES ARE IN THE UPPER 20S/LOW 30S
WHERE THE SKY IS CLEAR...AND IN THE MID 30S WHERE CLOUDS REMAIN.
THE LATEST RAP GUIDANCE INDICATES THESE CLOUDS WILL REMAIN AS IS
THROUGH THE REMAINDER OF THE NIGHT. WILL NEED TO CANCEL PART OF
THE FREEZE WARNING FOR THIS MORNING GIVEN THE LACK OF CLEARING
FROM THE WEST...ALTHOUGH WILL TAKE INTO ACCOUNT THE POSSIBILITY
FOR SOME CLEARING FROM THE WEST...AND ONLY CANCEL A PORTION OF
WEST CENTRAL MINNESOTA (FOR NOW).
TODAY...SINCE THE SFC HIGH SEEMS TO BE BUILDING IN A BIT SLOWER
THAN ANTICIPATED...WITH INCREASE SKY COVER...AND LOWER MAX TEMPS A
BIT. OTHERWISE...STILL ANTICIPATE CLEARING BY MID-LATE AFTERNOON
AS THE SFC HIGH OVERTAKES THE REGION.
TONIGHT...THE SFC HIGH WILL BE OVERHEAD THE ENTIRE NIGHT...AND
CLEAR SKY APPEARS VERY LIKELY. LOWERED THE MIN TEMPS TO VALUES
SIMILAR TO WHAT WE ARE EXPERIENCING CURRENTLY. ANTICIPATE ANOTHER
FREEZE WARNING BEING ISSUED BY THE DAY SHIFT.
FRIDAY..HIGH PRESSURE WILL LEAD TO MINIMAL MIXING...BUT AS THE
UPPER TROUGH GRADUALLY SHIFTS EAST CONVECTIVE TEMPS WILL BE
SLIGHTLY WARMER...LEADING TO LESS CU DEVELOPMENT AND SLIGHTLY
WARMER MAX TEMPS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT THU MAY 15 2014
FRIDAY NIGHT-SATURDAY NIGHT...ONE LAST NIGHT WITH NEAR FREEZING
TEMPERATURES FRIDAY NIGHT...ALTHOUGH VALUES SHOULD BE SLIGHTLY
WARMER THAN PREVIOUS NIGHTS. WEAK RETURN FLOW DEVELOPS
SATURDAY/SATURDAY NIGHT AS THE NEXT UPPER WAVE CRASHES THE PAC NW.
UPPER RIDGING WILL KEEP THE WX DRY...WITH TEMPERATURES APPROACHING
60F ON SATURDAY...AND REMAINING IN THE UPPER 30S/LOW 40S SATURDAY
NIGHT.
SUNDAY-WEDNESDAY... HIGH AMPLITUDE LONG WAVE PATTERN BECOMES MORE
ZONAL THIS PERIOD. FLOW ALOFT BECOMES MORE SPLIT DURING THIS PERIOD.
THE ECMWF WAS A FASTER SOLUTION THAN THE GFS. WILL PREFER A BLEND OF
THE GFS AND ECMWF.
LITTLE CHANGE TO TEMPS DURING THE PERIOD. A LITTLE WARMER FOR TUE
AND WED COMPARED TO YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1140 PM CDT WED MAY 14 2014
VFR CONDITIONS. CLEARING WILL WORK SOUTH AND EAST SLOWLY OVERNIGHT
WITH CLEARING GFK-TVF-FAR OVERNIGHT...BEMIDJI MIGHT SCATTER OUT
LATE TONIGHT. SUNSHINE TO START WILL WARM TEMPS AND THEN EXPECT A
SCT-BKN CU FIELD RRV INTO MINNESOTA THURSDAY AFTN. WINDS WILL BE
QUITE LIGHT FROM THE NORTH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
MN...FREEZE WARNING UNTIL 9 AM CDT THIS MORNING FOR MNZ001>009-
013>017-022-023-029.
&&
$$
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
228 AM EDT THU MAY 15 2014
.SYNOPSIS...
STRONG COLD FRONT CROSSES TODAY. HIGHEST THREAT OF FLOODING IS OVER
MOUNTAINOUS COUNTIES. MUCH COOLER IN ITS WAKE...INTO WEEKEND.
DISTURBANCES WITHIN MID/UPPER TROF PASSING FRIDAY AND SATURDAY.
&&
.NEAR TERM /THROUGH TODAY/...
MESOSCALE UPDATE
930 PM UPDATE...
CONVECTION HAS ALMOST CLEARED THE CWA. TORNADO WATCH EXPIRED. SCT
SHRA MOVING INTO PORTIONS OF NE KY. OTHERWISE MAINLY DRY UNTIL
AFTER MIDNIGHT WHEN BAND OF SLOW MOVING MOD SHRA MOVES IN FROM THE
W...AHEAD OF THE COLD FRONT.
PREVIOUS DISCUSSION BELOW...
ISOLATED TO SCATTERED STRONG/SVR CONVECTION ONGOING IN N REACHES
OF SE OH ZONES AND ALSO N WV LOWLANDS CLOSE TO OH RIVER. DECENT
SSE DOWNSLOPING FLOW EXTENDING UP ALL THE WAY INTO THE MID LEVELS
REALLY SERVING TO MITIGATE WIDESPREAD CONVECTION. THIS IS
ESPECIALLY TRUE FOR SW VA/S WV/NE KY WHERE THERE HAS BEEN NO
CONVECTION AS OF YET. HRRR SEEMS TO HAVE A GREAT HANDLE ON THINGS
AND RELIED HEAVILY ON IT FOR POPS. AS SUCH...NOT EXPECTING MUCH IN
THE WAY OF CONVECTION IN AFORMENTIONED LOCATIONS AS THE HRRR KEEPS
AREA MAINLY DRY THIS EVE AND EVEN UP INTO SE OH AND N WV ONCE
ONGOING CONVECTION MOVES OUT. THIS DOES MAKE SENSE GIVING STRONG
DEEP SSE DOWNSLOPING FLOW. HOWEVER...AFTER COORDINATION WITH
SPC...WILL HOLD ON TO THE WATCH TO BE ON SAFE SIDE. WILL WAIT FOR
ACTIVITY ACROSS W KY TO MOVE IN WELL AFTER MIDNIGHT AHEAD OF COLD
FRONT. EXPECT THIS TO BE MAINLY SHRA WITH PERHAPS SOME ELEVATED
CONVECTION.
PREVIOUS DISCUSSION BELOW...
AIRMASS BECOMING MORE UNSTABLE WITH HEATING THIS AFTERNOON. ANY
STORMS THAT DO DEVELOP COULD BECOME SEVERE AND POSSIBLY TORNADIC.
TOR WATCH IN EFFECT UNTIL 9PM TONIGHT. ALSO, ANY OF THESE STORMS
COULD PRODUCE RAINFALL UP TO AN INCH OR MORE PLUS SMALL HAIL.
CONVECTION SHOULD WAIN AFTER SUNSET AND SHOULD BE DONE BY MIDNIGHT
TONIGHT.
A STRONG COLD FRONT NOW STALLED OVER OH AND EXTENDS DOWN INTO KY
WILL MOVE EASTWARD AFTER A LOW PRESSURE WAVE MOVES UP AND ALONG
THE FRONT TONIGHT AND BE NORTH OF THE AREA BY 12Z THURSDAY.
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THIS FRONT SHOULD SHOULD
BE AFFECTING THE AREA SOMETIME AFTER 06Z TONIGHT. THE FRONT WILL
HAVE GOOD DYNAMICS AND PLENTY OF MOISTURE TO WORK WITH. RAIN AND
THUNDERSTORMS COULD PRODUCE UP TO 2+ INCHES OF RAIN BY FRIDAY
MORNING. SO HAVE ISSUED AN FFA UNTIL 12Z FRIDAY MORNING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
THE WEATHER TURNS PROGRESSIVELY COOLER THIS PERIOD AS A COUPLE OF
UPPER LEVEL DISTURBANCES DRIVE REINFORCING COLD FRONTS THROUGH.
ANY THUNDERSTORMS IN THE FAR NERN PORTION OF THE FCST AREA EARLY THU
EVENING WANE/EXIT QUICKLY...AS THE INITIAL COLD FRONT ROLLS ON
THROUGH. THIS WILL ALSO BRING THE RAIN TO AN END FROM W
TO E. WHILE THE MODELS WERE SIMILAR ON MOVING THE FRONT E OF THE
AREA EARLY FRI NT...NAM12/CMC WERE SLOWER WITH THE PRECIPITATION
WITH AN ANAFRONT LOOK TO IT. WENT WITH A COMPROMISE BUT A LITTLE
CLOSER TO THE SLOWER NAM/CMC CAMP. LOW CLOUDS LINGER INTO FRI.
TWO SIMILAR SYSTEMS THEN CROSS FRI AND SAT...MAINLY IN THE
AFTERNOON TO EARLY EVENING...BRINGING CLOUDS AND SOME SHOWERS.
THERE MAY STILL BE HINT OF INSTABILITY FRI SO INCLUDED THE SCHC FOR
THUNDER IN THE AFTERNOON AND EARLY EVENING. BY SAT...THE AIR MASS
IS TOO DRY AND STABLE FOR THUNDER.
BLENDED IN THE MET FOR HIGHS AND LOWS EARLY ON...WITH SOME HELP FROM
THE NAM THU NT...AS THE BAROCLINIC ZONE BEHIND THE FRONT MOVES
THROUGH. LOWS FRI NT LOOKED GOOD. BLENDED IN BIAS CORRECTED MEX
AND ECMWF FOR HIGHS SAT...BARELY ABOVE 60 OVER THE LOWLANDS BENEATH
H85 TEMPS NEAR 0 C. NOW HAVE SAT COOLER THAN FRI.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
USED THE ECMWF MEAN FOR THE PERIOD. THIS HAS AN UPPER LEVEL TROUGH
PROVIDING UNSEASONABLE COOL WEATHER FOR THE END OF THE WEEKEND. HIGH
PRESSURE THEN SLIDES OFF TO THE EAST FOR THE BEGINNING OF THE
WEEK...ALLOWING FOR SOME MODERATION IN TEMPERATURES. WARM FRONT
ARRIVES TUESDAY INTO WEDNESDAY...PROVIDING A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
BASING FORECAST ON THE FRONT PASSING THROUGH HTS TRI STATE AROUND
13Z...THEN REACHING NR A PKB-CRW-BKW LINE 16/17Z...THEN CKB/EKN
TOWARD 20/21Z.
HAVE WIDESPREAD SHOWERS ALONG FRONT WITH THE POSSIBILITY OF AN
EMBEDDED THUNDERSTORM DUE TO DYNAMICS. FURTHER NE...IN THE CKB TO
EKN VCNTY MAY BE ENOUGH TIME AHEAD OF THE FRONT...TO FORM A FEW
THUNDERSTORMS IN THE 15Z TO 19Z TIME FRAME.
CONDITIONS DETERIORATING FROM N TO S 08Z TO 14Z...WITH LOWEST
CONDITIONS ALONG AND IN THE WAKE OF THE FRONT...AS THE COOLER AIR
SQUEEZES OUT THE LOW LEVEL MOISTURE. HAVE WIDESPREAD IFR WITH
MOUNTAIN RIDGES OBSCURED.
CONDITIONS IMPROVING IN THE OHIO VALLEY DURING THE 20Z TO 23Z TIME
FRAME WITH LINGERING MVFR CEILINGS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF FRONT MAY VARY BY AN HOUR OR 2.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 05/15/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H M M M M M H H H
HTS CONSISTENCY H H H M M M M H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H M M M L
PKB CONSISTENCY H H H H H H M M M H H H
CKB CONSISTENCY H H H H H H H H M M M M
AFTER 06Z FRIDAY...
LINGERING IFR CEILINGS POSSIBLE IN WV CENTRAL MOUNTAINS 06Z TO 12Z
FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH THROUGH FRIDAY MORNING FOR WVZ005>011-013>020-
024>040-046-047.
OH...FLOOD WATCH THROUGH FRIDAY MORNING FOR OHZ066-067-075-076-
083>087.
KY...FLOOD WATCH THROUGH FRIDAY MORNING FOR KYZ101>103-105.
VA...FLOOD WATCH THROUGH FRIDAY MORNING FOR VAZ003-004.
&&
$$
SYNOPSIS...21/TRM/RPY
NEAR TERM...21/30
SHORT TERM...TRM
LONG TERM...RPY
AVIATION...KTB
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
339 PM CDT THU MAY 15 2014
.DISCUSSION...
.CURRENTLY...
SKIES ARE MOSTLY CLEAR ACROSS THE MID-SOUTH WITH TEMPERATURES
MAINLY IN THE MID 60S. SCATTERED SHOWERS AND THUNDERSTORMS ARE
JUST OFF TO OUR WEST AND APPROACHING NORTHEAST ARKANSAS RATHER
QUICKLY. LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW
ROTATING OVER THE UPPER MIDWEST WITH AN EMBEDDED SHORTWAVE IMPULSE
DIGGING INTO CENTRAL ARKANSAS. A FEW OF THESE STORMS HAVE ALREADY
REACHED SEVERE LIMITS FOR HAIL IN LITTLE ROCK`S CWA. AS THEY MOVE
EASTWARD INTO OUR AREA...SOME OF THESE STORMS MAY PRODUCE SMALL
HAIL AND POSSIBLY A FEW STRONG WIND GUSTS THIS AFTERNOON AND
EVENING. LOW AND MID LEVEL LAPSE RATES ARE QUITE HEALTHY AROUND 7
C/KM AND 8 C/KM RESPECTIVELY AND THE HAIL GROWTH ZONE IS RATHER
LOW DUE TO THE COLD CORE NATURE OF THE UPPER LEVEL SYSTEM.
.SHORT TERM...TONIGHT THROUGH THIS WEEKEND...
MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT ON THE OVERALL PATTERN
OVER THE NEXT 5 TO 7 DAYS. SHOWERS AND THUNDERSTORMS FROM THIS
AFTERNOON WILL DIMINISH IN COVERAGE AND WEAKEN AS THEY MOVE
THROUGH THE AREA INTO THE OVERNIGHT HOURS. THE AFOREMENTIONED
UPPER LEVEL LOW WILL REMAIN NEARLY STATIONARY OVER THE UPPER
MIDWEST THROUGH SATURDAY. AS A RESULT...THE MID-SOUTH WILL REMAIN
ON THE SOUTHERN PERIPHERY OF THIS SYSTEM AND A FEW SHORTWAVE WILL
MOVE THROUGH THE REGION. THIS WILL KEEP AT LEAST MENTIONABLE POPS
IN THE FORECAST THROUGH THE ENTIRE WEEKEND. THE BEST CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE LATE FRIDAY NIGHT INTO SATURDAY
MORNING AND AGAIN ON SATURDAY NIGHT INTO SUNDAY MORNING AS THE
STRONGEST WAVES MOVE THROUGH AT THAT TIME. TOTAL QPF VALUES WILL
MOST LIKELY REMAIN AROUND A HALF INCH OR BELOW. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL THROUGH THIS PERIOD AS COLD -25C
500MB TEMPERATURES REMAIN OVERHEAD. HIGHS WILL GENERALLY BE 10 TO
15 DEGREES BELOW NORMAL WITH HIGHS IN THE UPPER 60S TO LOWER 70S
AND OVERNIGHT LOWS IN THE UPPER 40S TO LOWER 50S.
.LONG TERM...MONDAY THROUGH NEXT WEEK...
UPPER LEVEL RIDGING WILL BEGIN ON MONDAY AND QUICKLY BECOME
AMPLIFIED BY MIDWEEK RESULTING IN MUCH WARMER TEMPERATURES AND DRY
CONDITIONS. HIGHS ON MONDAY WILL BE AROUND 80 AND TREND WARMER
EACH DAY WITH HIGHS NEAR 90 BY THURSDAY. IN ADDITION...HIGH
PRESSURE AT THE SURFACE WILL REMAIN ANCHORED OVER THE SOUTHEAST
SETTING UP MOIST RETURN FLOW OVER THE MID-SOUTH. THIS WILL RESULT
IN SUMMER-LIKE HOT AND HUMID CONDITIONS FOR THE LATTER PART OF THE
WEEK.
AC3
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE 24 HOUR TAF CYCLE. SHOWERS
WILL BEGIN TO DEVELOP THIS AFTERNOON BUT WILL REMAIN WIDESPREAD.
HAD ENOUGH CONFIDENCE IN HRRR GUIDANCE TO ADD VCSH TO KJBR AND
KMEM THROUGH 01/02 RESPECTIVELY. WINDS WILL BE LIGHT AND VARIABLE
TONIGHT BEFORE INCREASING FROM THE WEST BY NOON TOMORROW.
JPM3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
116 PM CDT THU MAY 15 2014
.UPDATE...
UPDATED FOR THE 18Z AVIATION DISCUSSION.
&&
UPDATE...MORNING UPDATE.
TEMPERATURES HAVE WARMED QUITE NICELY ACROSS THE MID-SOUTH AFTER A
CHILLY START. MOST AREAS ARE IN THE LOW TO MID 50S UNDER MOSTLY
SUNNY SKIES...EXCEPT NEAR THE TENNESSEE RIVER WHERE A LOW STRATUS
DECK IS KEEPING TEMPERATURES IN THE UPPER 40S. CLOUDS WILL
MOVE OUT WITHIN THE HOUR BEFORE MORE CLOUDS MOVE IN FROM THE WEST
BY THIS AFTERNOON AS A SHORTWAVE TROF ROTATES THROUGH. HIGHS WILL
RANGE FROM THE LOW TO MID 60S.
12Z HRRR MODEL RUN SUGGESTS THAT SCATTERED SHOWERS AND THUNDERSTORMS
WILL MOVE INTO NORTHEAST ARKANSAS AND WEST TENNESSEE BY THIS
AFTERNOON...AND EVENTUALLY INTO NORTH MISSISSIPPI BY EARLY
EVENING AS A SHORTWAVE MOVES THROUGH.
FORECAST IS ON TRACK AND NO CHANGES ARE NEEDED.
AC3
PREV DISCUSSION... /ISSUED 316 AM CDT THU MAY 15 2014/
.DISCUSSION...
LOW CLOUDS WITH SOME PATCHY DRIZZLE WILL CONTINUE TO HANG ON ACROSS
LOCATIONS GENERALLY EAST OF THE MISSISSIPPI RIVER THIS MORNING. THE
CLOUDS SHOULD CLEAR THE TENNESSEE RIVER AROUND MIDDAY.
MEANWHILE...ADDITIONAL CLOUDS WILL BEGIN TO MOVE IN FROM THE
NORTHWEST AS A SHORTWAVE MOVES INTO THE REGION. EXPECT ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE THIS
AFTERNOON. THE ACTIVITY WILL PUSH EAST THIS EVENING INTO THE
OVERNIGHT HOURS AS THE SHORTWAVE MOVES THROUGH. THE CLOUDS AND
CONVECTION WILL KEEP TEMPERATURES IN THE LOWER TO MID 60S FOR HIGHS.
LOWS TONIGHT WILL BE IN THE 40S.
A BROAD UPPER TROF WILL REMAIN LOCATED OVER THE MIDSOUTH THROUGH
THE END OF THE WEEK INTO THE WEEKEND. SEVERAL SHORTWAVES WILL
ROTATE AROUND THE BASE OF THE TROF AND WILL BRING OFF AND ON
CHANCES FOR SHOWERS. BEST CHANCES WILL OCCUR FRIDAY NIGHT INTO
SATURDAY. ANOTHER CHANCE WILL OCCUR LATE SATURDAY NIGHT INTO
SUNDAY AS A WARM FRONT TRIES TO LIFT NORTHWARD INTO THE CWA AS
ANOTHER SHORTWAVE MOVES IN. TEMPERATURES WILL REMAIN COOL WITH
HIGHS RANGING FROM THE MID 60S TO LOWER 70S. LOWS WILL BE IN THE
MID 40S TO MID 50S.
THE WARM FRONT WILL FINALLY LIFT NORTH ON MONDAY AS THE UPPER TROF
PUSHES EAST. AN UPPER RIDGE WILL QUICKLY BUILD INTO THE AREA BY
TUESDAY. A SUMMER TIME PATTERN WILL SET UP OVER THE MIDSOUTH BY
WEDNESDAY INTO THE END OF NEXT WEEK AS THE UPPER RIDGE BECOMES
CENTERED OVER THE AREA. TEMPERATURES WILL QUICKLY CLIMB AND EXPECT
HIGHS TO BE IN THE MID TO UPPER 80S BY TUESDAY AND WEDNESDAY. LOWS
WILL BE IN THE MID TO UPPER 60S.
KRM
.AVIATION...18Z TAF CYCLE
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE 24 HOUR TAF CYCLE. SHOWERS
WILL BEGIN TO DEVELOP THIS AFTERNOON BUT WILL REMAIN WIDESPREAD.
HAD ENOUGH CONFIDENCE IN HRRR GUIDANCE TO ADD VCSH TO KJBR AND
KMEM THROUGH 01/02 RESPECTIVELY. WINDS WILL BE LIGHT AND VARIABLE
TONIGHT BEFORE INCREASING FROM THE WEST BY NOON TOMORROW.
JPM3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1137 AM CDT THU MAY 15 2014
.DISCUSSION...
UPDATE FOR FORMATTING ISSUE.
&&
.PREV DISCUSSION... /ISSUED 952 AM CDT THU MAY 15 2014/
UPDATE...MORNING UPDATE.
TEMPERATURES HAVE WARMED QUITE NICELY ACROSS THE MID-SOUTH AFTER A
CHILLY START. MOST AREAS ARE IN THE LOW TO MID 50S UNDER MOSTLY
SUNNY SKIES...EXCEPT NEAR THE TENNESSEE RIVER WHERE A LOW STRATUS
DECK IS KEEPING TEMPERATURES IN THE UPPER 40S. CLOUDS WILL
MOVE OUT WITHIN THE HOUR BEFORE MORE CLOUDS MOVE IN FROM THE WEST
BY THIS AFTERNOON AS A SHORTWAVE TROF ROTATES THROUGH. HIGHS WILL
RANGE FROM THE LOW TO MID 60S.
12Z HRRR MODEL RUN SUGGESTS THAT SCATTERED SHOWERS AND THUNDERSTORMS
WILL MOVE INTO NORTHEAST ARKANSAS AND WEST TENNESSEE BY THIS
AFTERNOON...AND EVENTUALLY INTO NORTH MISSISSIPPI BY EARLY
EVENING AS A SHORTWAVE MOVES THROUGH.
FORECAST IS ON TRACK AND NO CHANGES ARE NEEDED.
AC3
&&
.PREV DISCUSSION... /ISSUED 316 AM CDT THU MAY 15 2014/
DISCUSSION...
LOW CLOUDS WITH SOME PATCHY DRIZZLE WILL CONTINUE TO HANG ON ACROSS
LOCATIONS GENERALLY EAST OF THE MISSISSIPPI RIVER THIS MORNING. THE
CLOUDS SHOULD CLEAR THE TENNESSEE RIVER AROUND MIDDAY.
MEANWHILE...ADDITIONAL CLOUDS WILL BEGIN TO MOVE IN FROM THE
NORTHWEST AS A SHORTWAVE MOVES INTO THE REGION. EXPECT ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE THIS
AFTERNOON. THE ACTIVITY WILL PUSH EAST THIS EVENING INTO THE
OVERNIGHT HOURS AS THE SHORTWAVE MOVES THROUGH. THE CLOUDS AND
CONVECTION WILL KEEP TEMPERATURES IN THE LOWER TO MID 60S FOR HIGHS.
LOWS TONIGHT WILL BE IN THE 40S.
A BROAD UPPER TROF WILL REMAIN LOCATED OVER THE MIDSOUTH THROUGH
THE END OF THE WEEK INTO THE WEEKEND. SEVERAL SHORTWAVES WILL
ROTATE AROUND THE BASE OF THE TROF AND WILL BRING OFF AND ON
CHANCES FOR SHOWERS. BEST CHANCES WILL OCCUR FRIDAY NIGHT INTO
SATURDAY. ANOTHER CHANCE WILL OCCUR LATE SATURDAY NIGHT INTO
SUNDAY AS A WARM FRONT TRIES TO LIFT NORTHWARD INTO THE CWA AS
ANOTHER SHORTWAVE MOVES IN. TEMPERATURES WILL REMAIN COOL WITH
HIGHS RANGING FROM THE MID 60S TO LOWER 70S. LOWS WILL BE IN THE
MID 40S TO MID 50S.
THE WARM FRONT WILL FINALLY LIFT NORTH ON MONDAY AS THE UPPER TROF
PUSHES EAST. AN UPPER RIDGE WILL QUICKLY BUILD INTO THE AREA BY
TUESDAY. A SUMMER TIME PATTERN WILL SET UP OVER THE MIDSOUTH BY
WEDNESDAY INTO THE END OF NEXT WEEK AS THE UPPER RIDGE BECOMES
CENTERED OVER THE AREA. TEMPERATURES WILL QUICKLY CLIMB AND EXPECT
HIGHS TO BE IN THE MID TO UPPER 80S BY TUESDAY AND WEDNESDAY. LOWS
WILL BE IN THE MID TO UPPER 60S.
KRM
&&
.AVIATION...12Z TAF CYCLE
CIGS HAVE ALREADY IMPROVED THIS MORNING AND FURTHER IMPROVEMENT IS
EXPECTED DURING THE DAY RESULTING IN VFR CONDITIONS FOR THE
MAJORITY OF THE TAF PERIOD. A FEW SHOWERS MAY DEVELOP THIS
AFTERNOON...BUT COVERAGE IS EXPECTED TO BE LIMITED. INCLUDED VCSH
AT JBR ONLY WHERE AFTERNOON COVERAGE MAY BE SLIGHTLY HIGHER. WINDS
WILL VARY BETWEEN WEST AND NORTHWEST GENERALLY 5-10KT.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
952 AM CDT THU MAY 15 2014
.UPDATE...MORNING UPDATE.
TEMPERATURES HAVE WARMED QUITE NICELY ACROSS THE MID-SOUTH AFTER A
CHILLY START. MOST AREAS ARE IN THE LOW TO MID 50S UNDER MOSTLY
SUNNY SKIES...EXCEPT NEAR THE TENNESSEE RIVER WHERE A LOW STRATUS
DECK IS KEEPING TEMPERATURES IN THE UPPER 40S. CLOUDS WILL
MOVE OUT WITHIN THE HOUR BEFORE MORE CLOUDS MOVE IN FROM THE WEST
BY THIS AFTERNOON AS A SHORTWAVE TROF ROTATES THROUGH. HIGHS WILL
RANGE FROM THE LOW TO MID 60S.
12Z HRRR MODEL RUN SUGGESTS THAT SCATTERED SHOWERS AND THUNDERSTORMS
WILL MOVE INTO NORTHEAST ARKANSAS AND WEST TENNESSEE BY THIS
AFTERNOON...AND EVENTUALLY INTO NORTH MISSISSIPPI BY EARLY
EVENING AS A SHORTWAVE MOVES THROUGH.
FORECAST IS ON TRACK AND NO CHANGES ARE NEEDED.
AC3
&&
PREV DISCUSSION... /ISSUED 316 AM CDT THU MAY 15 2014/
DISCUSSION...
LOW CLOUDS WITH SOME PATCHY DRIZZLE WILL CONTINUE TO HANG ON ACROSS
LOCATIONS GENERALLY EAST OF THE MISSISSIPPI RIVER THIS MORNING. THE
CLOUDS SHOULD CLEAR THE TENNESSEE RIVER AROUND MIDDAY.
MEANWHILE...ADDITIONAL CLOUDS WILL BEGIN TO MOVE IN FROM THE
NORTHWEST AS A SHORTWAVE MOVES INTO THE REGION. EXPECT ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE THIS
AFTERNOON. THE ACTIVITY WILL PUSH EAST THIS EVENING INTO THE
OVERNIGHT HOURS AS THE SHORTWAVE MOVES THROUGH. THE CLOUDS AND
CONVECTION WILL KEEP TEMPERATURES IN THE LOWER TO MID 60S FOR HIGHS.
LOWS TONIGHT WILL BE IN THE 40S.
A BROAD UPPER TROF WILL REMAIN LOCATED OVER THE MIDSOUTH THROUGH
THE END OF THE WEEK INTO THE WEEKEND. SEVERAL SHORTWAVES WILL
ROTATE AROUND THE BASE OF THE TROF AND WILL BRING OFF AND ON
CHANCES FOR SHOWERS. BEST CHANCES WILL OCCUR FRIDAY NIGHT INTO
SATURDAY. ANOTHER CHANCE WILL OCCUR LATE SATURDAY NIGHT INTO
SUNDAY AS A WARM FRONT TRIES TO LIFT NORTHWARD INTO THE CWA AS
ANOTHER SHORTWAVE MOVES IN. TEMPERATURES WILL REMAIN COOL WITH
HIGHS RANGING FROM THE MID 60S TO LOWER 70S. LOWS WILL BE IN THE
MID 40S TO MID 50S.
THE WARM FRONT WILL FINALLY LIFT NORTH ON MONDAY AS THE UPPER TROF
PUSHES EAST. AN UPPER RIDGE WILL QUICKLY BUILD INTO THE AREA BY
TUESDAY. A SUMMER TIME PATTERN WILL SET UP OVER THE MIDSOUTH BY
WEDNESDAY INTO THE END OF NEXT WEEK AS THE UPPER RIDGE BECOMES
CENTERED OVER THE AREA. TEMPERATURES WILL QUICKLY CLIMB AND EXPECT
HIGHS TO BE IN THE MID TO UPPER 80S BY TUESDAY AND WEDNESDAY. LOWS
WILL BE IN THE MID TO UPPER 60S.
KRM
&&
.AVIATION...12Z TAF CYCLE
CIGS HAVE ALREADY IMPROVED THIS MORNING AND FURTHER IMPROVEMENT IS
EXPECTED DURING THE DAY RESULTING IN VFR CONDITIONS FOR THE
MAJORITY OF THE TAF PERIOD. A FEW SHOWERS MAY DEVELOP THIS
AFTERNOON...BUT COVERAGE IS EXPECTED TO BE LIMITED. INCLUDED VCSH
AT JBR ONLY WHERE AFTERNOON COVERAGE MAY BE SLIGHTLY HIGHER. WINDS
WILL VARY BETWEEN WEST AND NORTHWEST GENERALLY 5-10KT.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1149 PM CDT WED MAY 14 2014
.UPDATE...
UPDATED FOR 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 705 PM CDT WED MAY 14 2014/
UPDATE...
UPDATED FOR 00Z AVIATION DISCUSSION
DISCUSSION...
PREV DISCUSSION... /ISSUED 636 PM CDT WED MAY 14 2014/
UPDATE...
A STRONG COLD FRONT HAS MOVED EAST OF THE MIDSOUTH WITH GUSTY
NORTHWEST WINDS PUSHING UNSEASONABLY COOL AIR INTO THE REGION.
ONLY PATCHY LIGHT RAIN AND DRIZZLE IS PRESENTLY OCCURRING ACROSS
PORTIONS OF THE FORECAST AREA. THE HRRR MODEL INDICATES SCATTERED
WRAP AROUND SHOWERS MOVING INTO MAINLY NORTHEAST AR...THE MO
BOOTHEEL AND WEST TN OVERNIGHT. UPDATED TO READJUST THE POPS FOR
TONIGHT AND MADE MINOR TWEAKS TO OTHER WEATHER ELEMENTS. UPDATED
ZONE FORECASTS AND GRIDS HAVE ALREADY BEEN SENT.
JCL
&&
.DISCUSSION... /ISSUED 238 PM CDT WED MAY 14 2014/
CURRENTLY...A 1012 MB SURFACE LOW WAS SITUATED NEAR CORINTH MS AT
18Z...TRACKING SLOWLY NNE...WITH A COLD FRONT EXTENDING THROUGH NE
MS. A LINE OF STRONG THUNDERSTORMS HAS DEVELOPED FROM NEAR THE
SURFACE LOW SOUTH ALONG THE COLD FRONT AND IS MOVING EAST. A
SEVERE THUNDERSTORM WATCH CONTINUES FOR EXTREME NE MS AND THE SE
PART OF WEST TN WHERE SBCAPES OF 500-1000 J/KG COMBINED WITH
INCREASING SHEAR MAY PRODUCE A FEW SEVERE THUNDERSTORMS WITH
DAMAGING WINDS OVER THE NEXT COUPLE OF HOURS. THE SURFACE LOW IS
BACKING THE LOW LEVEL WINDS SLIGHTLY SO A WEAK TORNADO CANNOT BE
RULED OUT.
TONIGHT...THE SURFACE LOW WILL MOVE INTO NRN MID TN THIS EVENING
WITH THE COLD FRONT PUSHING OUT OF THE AREA. THIS WILL END THE
SEVERE THREAT. THE PRECIP SHIELD ON THE NW SIDE OF THE SURFACE LOW
IS ALREADY LIFTING OUT SO WILL PROBABLY CANCEL THE FLASH FLOOD
WATCH OF EASTERN AR AND THE MO BOOTHEEL BY 4 PM. DROPPED POPS SOME
THIS EVENING AS PRECIP ASSOCD WITH SFC LOW LIFTS OUT A LITTLE
SOONER THOUGH KEPT AT LEAST SMALL CHANCES OVERNIGHT SINCE THE UPPER
TROF WILL BE PUSHING THROUGH. MUCH COOLER AIR WILL FLOOD THE
ENTIRE MIDSOUTH WITH LOWS IN THE 40S BY MORNING DESPITE PLENTIFUL
CLOUD COVER.
THURSDAY THROUGH FRIDAY...UPPER LOW WILL DROP INTO THE UPPER MS
VALLEY ON THURSDAY AND WOBBLE ON OVER TO THE GREAT LAKES ON
FRIDAY. DISTURBANCES WILL ROTATE AROUND THIS FEATURE BRINGING
PERIODS OF CLOUDS AND A FEW SHOWERS/ AFTN THUNDERSTORM TO THE
MIDSOUTH. TEMPS WILL BE MUCH COOLER THAN NORMAL WITH HIGHS IN THE
60S AND LOWS IN THE 40S THURSDAY NIGHT.
FRIDAY NIGHT INTO SUNDAY...AS THE UPPER LOW STARTS TO LIFT OUT A
WARM FRONT DEVELOPS OVER THE LOWER MS VALLEY DURING THIS PERIOD.
THIS FRONT WILL LIFT SLOWLY NORTH AND INTERACT WITH A COUPLE
UPPER LEVEL DISTURBANCES AND RESULT IN A CHANCE OF SHOWERS AND
MAYBE SOME ELEVATED THUNDER. MODELS ARE ALL IN PRETTY GOOD
AGREEMENT WITH A SWATH OF PRECIP LATE FRIDAY NIGHT INTO SATURDAY
MORNING ALONG AND NORTH OF THE TN/MS BORDER...TAPERING OFF
SATURDAY AFTN. ANOTHER ROUND IS POSSIBLE AGAIN SAT NIGHT INTO
SUNDAY MORNING. TEMPS WILL BE WARMING AS THE UPPER TROF LIFTS OUT
WITH HIGHS IN THE 70S BY SUNDAY.
MONDAY THROUGH WEDNESDAY...WARM FRONT LIFTS NORTH BY MONDAY AS
UPPER RIDGE BUILDS IN. WARM AND HUMID AIRMASS WILL SETTLE IN
THROUGH MIDWEEK WITH HIGHS WILL INTO THE 80S BY TUESDAY.
SJM
&&
.AVIATION...
06Z TAF CYCLE
IFR AND MVFR CIGS WILL PERSIST AT MEM...MKL AND TUP THROUGH THE
REMAINDER OF THE NIGHT...WHILE JBR WILL FLIRT BETWEEN VFR AND
MVFR. LIGHT DRIZZLE WILL ALSO BE PATCHY AT MEM AND MKL FOR A
COUPLE OF MORE HOURS. STILL EXPECTING IMPROVEMENT TO WIDESPREAD
VFR WEATHER BY MID MORNING. LATER IN THE PERIOD A WEAK DISTURBANCE
WILL BRING A THREAT FOR A LIGHT SHOWER AT JBR AND PERHAPS CLOSE TO MEM
AND MKL. A CRACK OF THUNDER MAY ALSO BE PRESENT...BUT WIDELY
SCATTERED IN COVERAGE. NORTHWEST WINDS AT 8-12 KTS WITH OCCASIONAL
GUSTS WILL BACK MORE SOUTHWEST TO WEST AND DIMINISH SOME LATE.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1233 PM EDT THU MAY 15 2014
.SYNOPSIS...
A SLOW MOVING FRONT ENTERS THE AREA TODAY WITH HEAVY RAIN
EXPECTED. THE FRONT WILL EXIT EAST OF THE PIEDMONT LATE TONIGHT.
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL KEEP US COOL INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1220 PM EDT THURSDAY...
RADAR TRENDS INDICATE THE LINE OF SHOWERS/ISOLATED THUNDERSTORMS
STRENGTHENING AS IT MOVES INTO A MORE UNSTABLE ATMOSPHERE EAST OF
THE BLUE RIDGE...WITH LIGHTNING STARTING TO INCREASE WITHIN THE
CONVECTION. LATEST MESO ANALYSIS SHOWS CAPE INCREASING ACROSS THE
COASTAL PLAIN INTO THE EASTERN PORTION OF OUR FORECAST AREA...AND
CONCERNED THAT A FEW CELLS DEVELOPING ALONG THE LINE WILL BECOME
CAPABLE OF PRODUCING LOCALLY STRONG TO DAMAGING WINDS. AS
SUCH...HAVE ISSUED A SEVERE THUNDERSTORM WATCH FOR OUR COUNTIES
AND INDEPENDENT CITIES ALONG AND EAST OF A LINE FROM CASWELLCOUNTY
IN NORTH CAROLINA TO ROCKBRIDGE COUNTY IN VIRGINIA.
AS OF 1000 AM EDT THURSDAY...
LATEST TRENDS INDICATE THAT THE MAIN LINE OF SHOWERS IS ADVANCING
FASTER THAN MODELS EARLIER INDICATED. LEADING LINE OF THE MAIN
SHOWER ACTIVITY...CURRENTLY STRETCHING NORTH TO SOUTH FROM THE
ALLEGHANY HIGHLANDS THROUGH THE NORTH CAROLINA PIEDMONT...IS
PRODUCING RAINFALL AMOUNTS RANGING GENERALLY FROM 0.6 TO 0.8
INCHES...WITH LOCALLY HEAVIER AMOUNTS. COLD FRONT IS CURRENTLY
MAKING ITS WAY ACROSS EASTERN KENTUCKY.
THE BACK EDGE OF HEAVIER PRECIPITATION IS GETTING READY TO ENTER
THE MOUNTAIN EMPIRE AND THE NORTH CAROLINA MOUNTAINS. HOWEVER...
MODELS STILL CALLING FOR A WAVE TO DEVELOP ALONG FRONT TO BRING A
RENEWED ROUND OF HEAVY RAIN TO THE AREA FROM THE NEW RIVER
EASTWARD DURING EARLY/MID AFTERNOON. THE BAND OF DEVELOPING
CONVECTION OVER NORTHERN GEORGIA AND EXTREME WESTERN SOUTH
CAROLINA MAY BE ASSOCIATED WITH THIS WAVE. AT ANY RATE...HAVE
ADJUSTED RAINFALL AMOUNTS FOR THIS AFTERNOON AND EVENING BASED ON
CURRENT RADAR TRENDS AS WELL AS THE RAPID UPDATE FORECAST MODELS.
SEE NO NEED TO MAKE CHANGES TO THE COVERAGE OF THE FLASH FLOOD
WATCH. ALSO ADJUSTED TEMPERATURES FOR TODAY...BASICALLY INDICATING
THAT TODAYS HIGHS WILL BE THE TEMPERATURE AT THE TIME WHEN THE
MAIN BAND OF SHOWERS ENTERS A GIVEN LOCATION.
PREVIOUS DISCUSSION AT 4 AM...
EXPANDED FLASH FLOOD WATCH EAST TO COVER REST OF THE PIEDMONT...PER
LATEST MODEL TRENDS AND GUIDANCE FROM WPC...AS WELL AS COLLABORATING
WITH NEIGHBORING OFFICES.
WILL SEE RAINFALL INCREASE OVER THE MOUNTAINS BY DAWN. ALREADY
GETTING MODERATE TO HEAVY RAIN SHOWERS INTO THE NC MTNS AND
FOOTHILLS. ALREADY SEEING ONE HALF TO TWO THIRDS OF AN INCH OF RAIN
ACROSS PORTIONS OF WATAUGA AND WILKES.
WV LOOP AND PWATS INDICATED STRONG MOISTURE TRANSPORT FROM THE GULF
AHEAD OF THE UPPER TROUGH AND FRONT. THERE IS ANOTHER CONNECTION
FROM THE SOUTHEAST ATLANTIC COAST AS WELL.
THESE TWO PLUMES OF MOISTURE WILL ENHANCE RAINFALL OVER THE REGION
THRU THIS EVENING.
IT LOOKS MORE LIKE A FLASH FLOOD SCENARIO GIVEN SE TO SOUTH FLOW
INTO THE MOUNTAINS WITH TRAINING ELEMENTS OF CONVECTION. POTENTIAL
ALSO EXISTS FOR RIVER FLOODING LATER TONIGHT-FRIDAY GIVEN SLOW
NATURE.
WOULD NOT BE SURPRISED TO SEE 4-5" AMOUNTS OVER PORTIONS OF THE BLUE
RIDGE FROM BOONE TO FLOYD AND PERHAPS UP TOWARD APPLE ORCHARD MTN.
ANOTHER ISSUE TODAY WILL BE SVR THREAT. THE WIND ENERGY WILL BE
THERE AS WELL AS HIGHER HUMIDITY. LIMITING FACTOR IS LACK OF
HEATING. STILL HIGH-RES MODELS SHOWING POTENTIAL FOR DISCRETE CELLS
AHEAD OF MAIN LINE THIS AFTERNOON EAST OF THE BLUE RIDGE...THEN THE
LINE ITSELF COULD HAVE EMBEDDED HIGH WIND THREAT. THIS IN CONCERT
WITH SPC/S SLIGHT RISK THREAT.
FORECAST HIGHS TODAY WILL BE TRICKY TO SAY THE LEAST GIVEN ONSET OF
RAIN EARLY WHICH MAY KEEP TEMPS FROM RISING MUCH IN THE WEST. LACK
OF SUNSHINE IN THE EAST BEFORE THE RAIN MAY ALLOW TEMPS TO RISE 10
DEGREES FROM THE UPPER 60S EARLY THIS MORNING TO NEAR 80.
MEANWHILE...THINK THE MOUNTAINS OF NC INTO SE WV WILL ONLY STAY
STEADY OR FALL ONCE THE RAIN MOVES IN. BLF CURRENTLY 68...SO HIGH
MAY ACTUALLY OCCUR AT DAYBREAK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
AS OF 230 AM EDT THURSDAY...
AXIS OF VERY HEAVY RAIN INCLUDING EMBEDDED CONVECTION WILL PUSH EAST
ACROSS MUCH OF THE REGION THIS EVENING BEFORE EXITING THE
PIEDMONT BY EARLY FRIDAY. WITH THE 85H BOUNDARY SLOW TO EXIT
THE MOUNTAINS AND ANOTHER WEAK WAVE RIDING UP THE FRONT...EXPECT THE
BAND TO STALL FOR A BIT AND TRAIN UP ALONG THE BLUE RIDGE FROM SOUTH
TO NORTH ESPCLY DURING THE EARLY EVENING AS WEAK IMPULSES SHEAR
THROUGH THE PLUME OF VERY HIGH PWATS ALONG/EAST OF THE MOUNTAINS.
THIS SHOULD BE THE PERIOD OF HEAVIEST RAIN WITH ADDED AMOUNTS OF 1-
2+ INCHES WEST OF THE BLUE RIDGE ROUGHLY BEFORE MIDNIGHT...AND OUT
EAST MIDNIGHT THROUGH DAWN FRIDAY PENDING HOW FAST THE BAND
SHIFTS EAST LATE AT NIGHT UNDER THE PARALLEL UPPER FLOW. LATEST
GUIDANCE IS A BIT FASTER NOW IN SLIDING THE BAND EAST ONCE THE
SURFACE WAVE DEVELOPS TO THE SOUTH AND HEADS NE SO SPED UP MOVEMENT
OF THE HEAVY RAIN AFTER MIDNIGHT AND REDUCED TOTALS A BIT ACROSS THE
WEST LATE. HOWEVER LOCALLY HIGHER TOTALS ALSO LIKELY AS EARLY SE
UPSLOPE INTERACTS WITH THE STRONG LIFT ALONG THE SOUTHERN BLUE RIDGE
BEFORE THE FLOW VEERS OVERNIGHT. INCREASING 85H JET ALONG WITH
STRONG SHEAR COULD ALSO SUPPORT SOME EMBEDDED SEVERE POTENTIAL
ESPCLY DURING THU EVENING BUT IFFY LIKELY GIVEN SUCH A DEFINED AXIS
OF HEAVY RAINFALL AND LACK OF DEEP INSTABILITY AFTER THE LEADING
EDGE PUSHES ACROSS. THUS CONTINUED WITH CAT POPS THIS EVENING WITH A
FASTER EASTWARD SHIFT DURING THE OVERNIGHT WITH MOST HIGH POPS
CONFINED EAST OF THE BLUE RIDGE SHORTLY AFTER MIDNIGHT...AND
BASICALLY LOW CHANCES FAR EAST BY DAWN FRIDAY.
SURFACE FRONT FINALLY SHIFTS TO THE EAST FRIDAY AS WEAK LOW PRESSURE
HEADS TOWARD DELMARVA BY AFTERNOON. HOWEVER THE UPPER COLD POOL LAGS
BACK WITH THE COMBO OF SW FLOW ALOFT AND COOLING LIKELY ALLOWING FOR
A FEW ADDED -SHRA BANDS TO DEVELOP MAINLY WEST FRIDAY INTO FRIDAY
EVENING WITH WEAK DOWNSLOPE DRYING IN THE EAST. YET ANOTHER
SHORTWAVE WILL ROTATE UNDER THE 5H TROUGH BY SATURDAY WITH PERHAPS
ANOTHER UPSLOPE AIDED ROUND OF MOUNTAIN SHOWERS POSSIBLE INTO SAT
NIGHT SO KEPT IN LOW CHANCE POPS WEST.
OTRW THE PASSING FRONT TO START THE ONSET OF COOL ADVECTION LATER
TONIGHT WITH THE BRUNT OF THE 85H COOLING TAKING PLACE EARLY IN THE
WEEKEND. THIS LIKELY TO KEEP MOUNTAIN HIGHS IN THE 60S BOTH FRIDAY
AND SATURDAY WITH LOWS IN THE 40S AND PERHAPS SOME 30S DEEPER
VALLEYS LATE FRIDAY NIGHT AS SURFACE HIGH PRESSURE SETTLES
OVER THE WEST. EASTERN SECTIONS SHOULD BE ABLE TO SCRAPE IN THE
LOW/MID 70S FOR HIGHS BUT PERHAPS ONLY THAT WARM IN THE PIEDMONT BY
SATURDAY AFTERNOON.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1205 PM EDT WEDNESDAY...
CENTER OF THE STRONG UPPER TROUGH FOR MID/LATE MAY WILL PASS ACROSS
THE REGION SUNDAY AND THEN BEGIN TO SLOWLY LIFT OUT TO THE NE INTO
EARLY AND MID WEEK. THIS WILL RESULT IN AN EXTENDED PERIOD OF BELOW
NORMAL TEMPS THROUGH MUCH OF THE PERIOD...WITH CHILLY OVERNIGHT LOWS
ESPCLY IN THE MOUNTAIN VALLEYS EARLY NEXT WEEK WHEN SURFACE HIGH
PRESSURE SHOULD BE OVERHEAD. WITH THE COLD POOL ACROSS THE REGION
SUNDAY...MAY BE ENOUGH RESIDUAL MOISTURE TO HELP POP ISOLATED
AFTERNOON -SHRA MAINLY OVER THE NW SO KEPT IN A LOW POP THERE. OTRW
MODELS SHOW A PROLONGED PERIOD OF NW FLOW ALOFT ON THE BACK OF THE
DEPARTING 5H TROUGH WHILE UNDERCUTTING WITH WEAK HIGH PRESSURE IN
THE WAKE OF THIS SYSTEM. THIS SUPPORTS DRIER LOW LEVELS MONDAY INTO
TUESDAY WITH ANY IMPULSES ALOFT ONLY RESULTING IN AFTERNOON CU AND
ISOLATED -SHRA AT BEST. WARM ADVECTION PATTERN STARTS TO SHIFT EAST
BY MID WEEK WITH MODELS SHOWING A MORE DISTINCT WAVE SLIDING SE IN
ADVANCE OF A WARM FRONT ACROSS THE MIDWEST. EARLIER EC MOST
AGGRESSIVE WITH THIS FEATURE WITH POSSIBLE MCS BUT WAY TOO EARLY TO
TIME THIS ESPCLY GIVEN GUIDANCE DIFFERENCES. THUS INCLUDING A BIT
HIGHER POP ON DAY7 FOR NOW.
OTRW MAINLY PC WITH COMFORTABLE HIGHS IN THE 60S TO LOW 70S EARLY
ON...REBOUNDING TO MOSTLY 70S BY WED. LOWS MOSTLY IN THE 40S WITH
PERHAPS COLD ENOUGH 30S FOR SOME PATCHY DEEP VALLEY FROST
SUNDAY/MONDAY MORNINGS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 740 AM EDT THURSDAY...
AVIATION FORECAST TO FOLLOW LATEST RAP AND NEAR TERM RADAR/SAT
TRENDS. WILL SEE A PERIOD OF MODERATE TO HEAVY RAIN OVER BCB AT
12Z...ENDING BY 13Z. STILL THINKING THE CIGS/VSBYS WILL STAY MVFR
OR LOWER TODAY WITH PERIODS OF MODERATE TO HEAVY SHOWERS WITH
EMBEDDED TSRA. MODELS FAVOR SLOW DOWN BUT LATEST TRENDS THIS
MORNING PER RADAR/SAT INDICATE THAT BLF COULD DRY OUT FASTER. WILL
HANG ONTO THE PREVIOUS FORECAST FROM 06Z BUT SPEED THINGS UP ABOUT
1-2 HRS. OVERNIGHT...THE EAST WILL STAY WITH SHOWERS WHILE WEST
WINDS DRY THINGS ACROSS THE WEST...ALTHOUGH LOW LVL MOISTURE WILL
LINGER INTO THE END OF THE TAF PERIOD.
STILL LOOKS LIKE POOR AVIATION CONDITIONS THRU MUCH OF THE TAF
PERIOD...WITH STRONG/SVR CONVECTION ALSO POSSIBLE ESPECIALLY EAST
OF THE MOUNTAINS THIS AFTERNOON.
EXTENDED AVIATION DISCUSSION...
EXPECT CONDITIONS TO IMPROVE AT ROA/LYH/DAN BY 12Z FRIDAY TO
VFR...AND THE MOUNTAINS SHOULD START TO SCOUR OUT DURING THE DAY
FRIDAY...BUT WITH UPPER LOW MOVING IN SOME SCT SHOWERS AND MVFR
CIGS POSSIBLE.
THIS LARGE UPPER LOW PRESSURE AREA WILL BECOME ANCHORED ACROSS
THE GREAT LAKES REGION THROUGH THE WEEKEND AND POSSIBLY INTO EARLY
NEXT WEEK. THIS WILL KEEP AN UNSTABLE/UNSETTLED WEATHER PATTERN IN
PLACE WITH BKN MVFR CIGS REMAINING POSSIBLE AT TIMES ALONG WITH
SCT -SHRA...ESPECIALLY ACROSS THE MOUNTAINS...IMPACTING
LWB/BLF/BCB THE MOST THROUGH THE WEEKEND.
&&
.HYDROLOGY...
AS OF 405 AM EDT THURSDAY...
FLASH FLOOD WATCH EXPANDED EAST TO COVER REST OF THE PIEDMONT.
STILL LOOKS LIKE 1-3 INCHES LIKELY FOR AREAL AVERAGE. AREAS ALONG
THE BLUE RIDGE ARE MORE THAN LIKELY GOING TO SEE ISOLATED AMOUNTS
OF 4-5" WITH RAINFALL RATES EXCEEDING 1.5" IN THUNDERSTORMS ALONG
WITH TRAINING OF ECHOES.
ALSO...GIVEN THIS AMOUNT OF RAINFALL...DO NOT BE SURPRISED TO SEE
A FEW MAIN STEM RIVER POINTS HEAD TOWARD MINOR FLOODING DEPENDING
ON HOW THE RAINFALL TOTALS PAN OUT AND WHICH BASINS GET THE MOST.
GEFS AND NAEFS RIVER ENSEMBLE FORECASTS STILL FAVORING THE
GREENBRIER TO GET HIT THE HARDEST POTENTIALLY GETTING TO MODERATE
FLOOD AT ALDERSON. MEANWHILE...THREAT OF MINOR FLOODING EXISTS
ALONG THE LOWER DAN AND ROANOKE RIVERS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR VAZ010>020-022>024-
032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ001>006-018>020.
WV...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR WVZ042>045.
&&
$$
SYNOPSIS...WP
NEAR TERM...NF/WP
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/RAB/WP
HYDROLOGY...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1016 AM EDT THU MAY 15 2014
.SYNOPSIS...
A SLOW MOVING FRONT ENTERS THE AREA TODAY WITH HEAVY RAIN
EXPECTED. THE FRONT WILL EXIT EAST OF THE PIEDMONT LATE TONIGHT.
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL KEEP US COOL INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1000 AM EDT THURSDAY...
LATEST TRENDS INDICATE THAT THE MAIN LINE OF SHOWERS IS ADVANCING
FASTER THAN MODELS EARLIER INDICATED. LEADING LINE OF THE MAIN
SHOWER ACTIVITY...CURRENTLY STRETCHING NORTH TO SOUTH FROM THE
ALLEGHANY HIGHLANDS THROUGH THE NORTH CAROLINA PIEDMONT...IS
PRODUCING RAINFALL AMOUNTS RANGING GENERALLY FROM 0.6 TO 0.8
INCHES...WITH LOCALLY HEAVIER AMOUNTS. COLD FRONT IS CURRENTLY
MAKING ITS WAY ACROSS EASTERN KENTUCKY.
THE BACK EDGE OF HEAVIER PRECIPITATION IS GETTING READY TO ENTER
THE MOUNTAIN EMPIRE AND THE NORTH CAROLINA MOUNTAINS. HOWEVER...
MODELS STILL CALLING FOR A WAVE TO DEVELOP ALONG FRONT TO BRING A
RENEWED ROUND OF HEAVY RAIN TO THE AREA FROM THE NEW RIVER
EASTWARD DURING EARLY/MID AFTERNOON. THE BAND OF DEVELOPING
CONVECTION OVER NORTHERN GEORGIA AND EXTREME WESTERN SOUTH
CAROLINA MAY BE ASSOCIATED WITH THIS WAVE. AT ANY RATE...HAVE
ADJUSTED RAINFALL AMOUNTS FOR THIS AFTERNOON AND EVENING BASED ON
CURRENT RADAR TRENDS AS WELL AS THE RAPID UPDATE FORECAST MODELS.
SEE NO NEED TO MAKE CHANGES TO THE COVERAGE OF THE FLASH FLOOD
WATCH. ALSO ADJUSTED TEMPERATURES FOR TODAY...BASICALLY INDICATING
THAT TODAYS HIGHS WILL BE THE TEMPERATURE AT THE TIME WHEN THE
MAIN BAND OF SHOWERS ENTERS A GIVEN LOCATION.
PREVIOUS DISCUSSION AT 4 AM...
EXPANDED FLASH FLOOD WATCH EAST TO COVER REST OF THE PIEDMONT...PER
LATEST MODEL TRENDS AND GUIDANCE FROM WPC...AS WELL AS COLLABORATING
WITH NEIGHBORING OFFICES.
WILL SEE RAINFALL INCREASE OVER THE MOUNTAINS BY DAWN. ALREADY
GETTING MODERATE TO HEAVY RAIN SHOWERS INTO THE NC MTNS AND
FOOTHILLS. ALREADY SEEING ONE HALF TO TWO THIRDS OF AN INCH OF RAIN
ACROSS PORTIONS OF WATAUGA AND WILKES.
WV LOOP AND PWATS INDICATED STRONG MOISTURE TRANSPORT FROM THE GULF
AHEAD OF THE UPPER TROUGH AND FRONT. THERE IS ANOTHER CONNECTION
FROM THE SOUTHEAST ATLANTIC COAST AS WELL.
THESE TWO PLUMES OF MOISTURE WILL ENHANCE RAINFALL OVER THE REGION
THRU THIS EVENING.
IT LOOKS MORE LIKE A FLASH FLOOD SCENARIO GIVEN SE TO SOUTH FLOW
INTO THE MOUNTAINS WITH TRAINING ELEMENTS OF CONVECTION. POTENTIAL
ALSO EXISTS FOR RIVER FLOODING LATER TONIGHT-FRIDAY GIVEN SLOW
NATURE.
WOULD NOT BE SURPRISED TO SEE 4-5" AMOUNTS OVER PORTIONS OF THE BLUE
RIDGE FROM BOONE TO FLOYD AND PERHAPS UP TOWARD APPLE ORCHARD MTN.
ANOTHER ISSUE TODAY WILL BE SVR THREAT. THE WIND ENERGY WILL BE
THERE AS WELL AS HIGHER HUMIDITY. LIMITING FACTOR IS LACK OF
HEATING. STILL HIGH-RES MODELS SHOWING POTENTIAL FOR DISCRETE CELLS
AHEAD OF MAIN LINE THIS AFTERNOON EAST OF THE BLUE RIDGE...THEN THE
LINE ITSELF COULD HAVE EMBEDDED HIGH WIND THREAT. THIS IN CONCERT
WITH SPC/S SLIGHT RISK THREAT.
FORECAST HIGHS TODAY WILL BE TRICKY TO SAY THE LEAST GIVEN ONSET OF
RAIN EARLY WHICH MAY KEEP TEMPS FROM RISING MUCH IN THE WEST. LACK
OF SUNSHINE IN THE EAST BEFORE THE RAIN MAY ALLOW TEMPS TO RISE 10
DEGREES FROM THE UPPER 60S EARLY THIS MORNING TO NEAR 80.
MEANWHILE...THINK THE MOUNTAINS OF NC INTO SE WV WILL ONLY STAY
STEADY OR FALL ONCE THE RAIN MOVES IN. BLF CURRENTLY 68...SO HIGH
MAY ACTUALLY OCCUR AT DAYBREAK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
AS OF 230 AM EDT THURSDAY...
AXIS OF VERY HEAVY RAIN INCLUDING EMBEDDED CONVECTION WILL PUSH EAST
ACROSS MUCH OF THE REGION THIS EVENING BEFORE EXITING THE
PIEDMONT BY EARLY FRIDAY. WITH THE 85H BOUNDARY SLOW TO EXIT
THE MOUNTAINS AND ANOTHER WEAK WAVE RIDING UP THE FRONT...EXPECT THE
BAND TO STALL FOR A BIT AND TRAIN UP ALONG THE BLUE RIDGE FROM SOUTH
TO NORTH ESPCLY DURING THE EARLY EVENING AS WEAK IMPULSES SHEAR
THROUGH THE PLUME OF VERY HIGH PWATS ALONG/EAST OF THE MOUNTAINS.
THIS SHOULD BE THE PERIOD OF HEAVIEST RAIN WITH ADDED AMOUNTS OF 1-
2+ INCHES WEST OF THE BLUE RIDGE ROUGHLY BEFORE MIDNIGHT...AND OUT
EAST MIDNIGHT THROUGH DAWN FRIDAY PENDING HOW FAST THE BAND
SHIFTS EAST LATE AT NIGHT UNDER THE PARALLEL UPPER FLOW. LATEST
GUIDANCE IS A BIT FASTER NOW IN SLIDING THE BAND EAST ONCE THE
SURFACE WAVE DEVELOPS TO THE SOUTH AND HEADS NE SO SPED UP MOVEMENT
OF THE HEAVY RAIN AFTER MIDNIGHT AND REDUCED TOTALS A BIT ACROSS THE
WEST LATE. HOWEVER LOCALLY HIGHER TOTALS ALSO LIKELY AS EARLY SE
UPSLOPE INTERACTS WITH THE STRONG LIFT ALONG THE SOUTHERN BLUE RIDGE
BEFORE THE FLOW VEERS OVERNIGHT. INCREASING 85H JET ALONG WITH
STRONG SHEAR COULD ALSO SUPPORT SOME EMBEDDED SEVERE POTENTIAL
ESPCLY DURING THU EVENING BUT IFFY LIKELY GIVEN SUCH A DEFINED AXIS
OF HEAVY RAINFALL AND LACK OF DEEP INSTABILITY AFTER THE LEADING
EDGE PUSHES ACROSS. THUS CONTINUED WITH CAT POPS THIS EVENING WITH A
FASTER EASTWARD SHIFT DURING THE OVERNIGHT WITH MOST HIGH POPS
CONFINED EAST OF THE BLUE RIDGE SHORTLY AFTER MIDNIGHT...AND
BASICALLY LOW CHANCES FAR EAST BY DAWN FRIDAY.
SURFACE FRONT FINALLY SHIFTS TO THE EAST FRIDAY AS WEAK LOW PRESSURE
HEADS TOWARD DELMARVA BY AFTERNOON. HOWEVER THE UPPER COLD POOL LAGS
BACK WITH THE COMBO OF SW FLOW ALOFT AND COOLING LIKELY ALLOWING FOR
A FEW ADDED -SHRA BANDS TO DEVELOP MAINLY WEST FRIDAY INTO FRIDAY
EVENING WITH WEAK DOWNSLOPE DRYING IN THE EAST. YET ANOTHER
SHORTWAVE WILL ROTATE UNDER THE 5H TROUGH BY SATURDAY WITH PERHAPS
ANOTHER UPSLOPE AIDED ROUND OF MOUNTAIN SHOWERS POSSIBLE INTO SAT
NIGHT SO KEPT IN LOW CHANCE POPS WEST.
OTRW THE PASSING FRONT TO START THE ONSET OF COOL ADVECTION LATER
TONIGHT WITH THE BRUNT OF THE 85H COOLING TAKING PLACE EARLY IN THE
WEEKEND. THIS LIKELY TO KEEP MOUNTAIN HIGHS IN THE 60S BOTH FRIDAY
AND SATURDAY WITH LOWS IN THE 40S AND PERHAPS SOME 30S DEEPER
VALLEYS LATE FRIDAY NIGHT AS SURFACE HIGH PRESSURE SETTLES
OVER THE WEST. EASTERN SECTIONS SHOULD BE ABLE TO SCRAPE IN THE
LOW/MID 70S FOR HIGHS BUT PERHAPS ONLY THAT WARM IN THE PIEDMONT BY
SATURDAY AFTERNOON.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1205 PM EDT WEDNESDAY...
CENTER OF THE STRONG UPPER TROUGH FOR MID/LATE MAY WILL PASS ACROSS
THE REGION SUNDAY AND THEN BEGIN TO SLOWLY LIFT OUT TO THE NE INTO
EARLY AND MID WEEK. THIS WILL RESULT IN AN EXTENDED PERIOD OF BELOW
NORMAL TEMPS THROUGH MUCH OF THE PERIOD...WITH CHILLY OVERNIGHT LOWS
ESPCLY IN THE MOUNTAIN VALLEYS EARLY NEXT WEEK WHEN SURFACE HIGH
PRESSURE SHOULD BE OVERHEAD. WITH THE COLD POOL ACROSS THE REGION
SUNDAY...MAY BE ENOUGH RESIDUAL MOISTURE TO HELP POP ISOLATED
AFTERNOON -SHRA MAINLY OVER THE NW SO KEPT IN A LOW POP THERE. OTRW
MODELS SHOW A PROLONGED PERIOD OF NW FLOW ALOFT ON THE BACK OF THE
DEPARTING 5H TROUGH WHILE UNDERCUTTING WITH WEAK HIGH PRESSURE IN
THE WAKE OF THIS SYSTEM. THIS SUPPORTS DRIER LOW LEVELS MONDAY INTO
TUESDAY WITH ANY IMPULSES ALOFT ONLY RESULTING IN AFTERNOON CU AND
ISOLATED -SHRA AT BEST. WARM ADVECTION PATTERN STARTS TO SHIFT EAST
BY MID WEEK WITH MODELS SHOWING A MORE DISTINCT WAVE SLIDING SE IN
ADVANCE OF A WARM FRONT ACROSS THE MIDWEST. EARLIER EC MOST
AGGRESSIVE WITH THIS FEATURE WITH POSSIBLE MCS BUT WAY TOO EARLY TO
TIME THIS ESPCLY GIVEN GUIDANCE DIFFERENCES. THUS INCLUDING A BIT
HIGHER POP ON DAY7 FOR NOW.
OTRW MAINLY PC WITH COMFORTABLE HIGHS IN THE 60S TO LOW 70S EARLY
ON...REBOUNDING TO MOSTLY 70S BY WED. LOWS MOSTLY IN THE 40S WITH
PERHAPS COLD ENOUGH 30S FOR SOME PATCHY DEEP VALLEY FROST
SUNDAY/MONDAY MORNINGS.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
AS OF 740 AM EDT THURSDAY...
AVIATION FORECAST TO FOLLOW LATEST RAP AND NEAR TERM RADAR/SAT
TRENDS. WILL SEE A PERIOD OF MODERATE TO HEAVY RAIN OVER BCB AT
12Z...ENDING BY 13Z. STILL THINKING THE CIGS/VSBYS WILL STAY MVFR
OR LOWER TODAY WITH PERIODS OF MODERATE TO HEAVY SHOWERS WITH
EMBEDDED TSRA. MODELS FAVOR SLOW DOWN BUT LATEST TRENDS THIS
MORNING PER RADAR/SAT INDICATE THAT BLF COULD DRY OUT FASTER. WILL
HANG ONTO THE PREVIOUS FORECAST FROM 06Z BUT SPEED THINGS UP ABOUT
1-2 HRS. OVERNIGHT...THE EAST WILL STAY WITH SHOWERS WHILE WEST
WINDS DRY THINGS ACROSS THE WEST...ALTHOUGH LOW LVL MOISTURE WILL
LINGER INTO THE END OF THE TAF PERIOD.
STILL LOOKS LIKE POOR AVIATION CONDITIONS THRU MUCH OF THE TAF
PERIOD...WITH STRONG/SVR CONVECTION ALSO POSSIBLE ESPECIALLY EAST
OF THE MOUNTAINS THIS AFTERNOON.
EXTENDED AVIATION DISCUSSION...
EXPECT CONDITIONS TO IMPROVE AT ROA/LYH/DAN BY 12Z FRIDAY TO
VFR...AND THE MOUNTAINS SHOULD START TO SCOUR OUT DURING THE DAY
FRIDAY...BUT WITH UPPER LOW MOVING IN SOME SCT SHOWERS AND MVFR
CIGS POSSIBLE.
THIS LARGE UPPER LOW PRESSURE AREA WILL BECOME ANCHORED ACROSS
THE GREAT LAKES REGION THROUGH THE WEEKEND AND POSSIBLY INTO EARLY
NEXT WEEK. THIS WILL KEEP AN UNSTABLE/UNSETTLED WEATHER PATTERN IN
PLACE WITH BKN MVFR CIGS REMAINING POSSIBLE AT TIMES ALONG WITH
SCT -SHRA...ESPECIALLY ACROSS THE MOUNTAINS...IMPACTING
LWB/BLF/BCB THE MOST THROUGH THE WEEKEND.
&&
.HYDROLOGY...
AS OF 405 AM EDT THURSDAY...
FLASH FLOOD WATCH EXPANDED EAST TO COVER REST OF THE PIEDMONT.
STILL LOOKS LIKE 1-3 INCHES LIKELY FOR AREAL AVERAGE. AREAS ALONG
THE BLUE RIDGE ARE MORE THAN LIKELY GOING TO SEE ISOLATED AMOUNTS
OF 4-5" WITH RAINFALL RATES EXCEEDING 1.5" IN THUNDERSTORMS ALONG
WITH TRAINING OF ECHOES.
ALSO...GIVEN THIS AMOUNT OF RAINFALL...DO NOT BE SURPRISED TO SEE
A FEW MAIN STEM RIVER POINTS HEAD TOWARD MINOR FLOODING DEPENDING
ON HOW THE RAINFALL TOTALS PAN OUT AND WHICH BASINS GET THE MOST.
GEFS AND NAEFS RIVER ENSEMBLE FORECASTS STILL FAVORING THE
GREENBRIER TO GET HIT THE HARDEST POTENTIALLY GETTING TO MODERATE
FLOOD AT ALDERSON. MEANWHILE...THREAT OF MINOR FLOODING EXISTS
ALONG THE LOWER DAN AND ROANOKE RIVERS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR VAZ010>020-022>024-
032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ001>006-018>020.
WV...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR WVZ042>045.
&&
$$
SYNOPSIS...WP
NEAR TERM...NF/WP
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/RAB/WP
HYDROLOGY...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
753 AM EDT THU MAY 15 2014
.SYNOPSIS...
A SLOW MOVING FRONT ENTERS THE AREA TODAY WITH HEAVY RAIN
EXPECTED. THE FRONT WILL EXIT EAST OF THE PIEDMONT LATE TONIGHT.
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL KEEP US COOL INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 745 AM EDT THURSDAY...
LINE OF SHOWERS ADVANCING FASTER TO THE NORTHEAST THAN EARLIER
FORECAST. ADJUSTED POPS ACCORDING TO LATEST RADAR TRENDS WHICH
FAVORS THE LATER RAP13. MODELS SHOWING THAT THIS LINE SHOULD
BEGIN TO SLOW DOWN AS ANOTHER WAVE FORMS ALONG THE FRONT TO THE
SOUTH. HOWEVER...CONCERN IS THAT DRY AIR OVER MID TN TO GA/AL LINE
MAY SLIDE INTO THE SRN APPALACHIANS SOONER CUTTING DOWN ON PRECIP
AMOUNTS. THIS WILL BE A BLESSING AS FOLKS IN THE NC MTNS HAVE
ALREADY GOTTEN UP TO 2". HOWEVER...LEANED TOWARD LATEST MODEL RUNS
STILL SHOWING MAX AMOUNTS ACROSS THE BLUE RIDGE ESPECIALLY FROM
FLOYD NORTH TO THE SRN SHENANDOAH VLY THIS AFTERNOON...SO NOT
CHANGING WATCH AT THIS TIME.
PREVIOUS DISCUSSION AT 4 AM...
EXPANDED FLASH FLOOD WATCH EAST TO COVER REST OF THE PIEDMONT...PER
LATEST MODEL TRENDS AND GUIDANCE FROM WPC...AS WELL AS COLLABORATING
WITH NEIGHBORING OFFICES.
WILL SEE RAINFALL INCREASE OVER THE MOUNTAINS BY DAWN. ALREADY
GETTING MODERATE TO HEAVY RAIN SHOWERS INTO THE NC MTNS AND
FOOTHILLS. ALREADY SEEING ONE HALF TO TWO THIRDS OF AN INCH OF RAIN
ACROSS PORTIONS OF WATAUGA AND WILKES.
WV LOOP AND PWATS INDICATED STRONG MOISTURE TRANSPORT FROM THE GULF
AHEAD OF THE UPPER TROUGH AND FRONT. THERE IS ANOTHER CONNECTION
FROM THE SOUTHEAST ATLANTIC COAST AS WELL.
THESE TWO PLUMES OF MOISTURE WILL ENHANCE RAINFALL OVER THE REGION
THRU THIS EVENING.
IT LOOKS MORE LIKE A FLASH FLOOD SCENARIO GIVEN SE TO SOUTH FLOW
INTO THE MOUNTAINS WITH TRAINING ELEMENTS OF CONVECTION. POTENTIAL
ALSO EXISTS FOR RIVER FLOODING LATER TONIGHT-FRIDAY GIVEN SLOW
NATURE.
WOULD NOT BE SURPRISED TO SEE 4-5" AMOUNTS OVER PORTIONS OF THE BLUE
RIDGE FROM BOONE TO FLOYD AND PERHAPS UP TOWARD APPLE ORCHARD MTN.
ANOTHER ISSUE TODAY WILL BE SVR THREAT. THE WIND ENERGY WILL BE
THERE AS WELL AS HIGHER HUMIDITY. LIMITING FACTOR IS LACK OF
HEATING. STILL HIGH-RES MODELS SHOWING POTENTIAL FOR DISCRETE CELLS
AHEAD OF MAIN LINE THIS AFTERNOON EAST OF THE BLUE RIDGE...THEN THE
LINE ITSELF COULD HAVE EMBEDDED HIGH WIND THREAT. THIS IN CONCERT
WITH SPC/S SLIGHT RISK THREAT.
FORECAST HIGHS TODAY WILL BE TRICKY TO SAY THE LEAST GIVEN ONSET OF
RAIN EARLY WHICH MAY KEEP TEMPS FROM RISING MUCH IN THE WEST. LACK
OF SUNSHINE IN THE EAST BEFORE THE RAIN MAY ALLOW TEMPS TO RISE 10
DEGREES FROM THE UPPER 60S EARLY THIS MORNING TO NEAR 80.
MEANWHILE...THINK THE MOUNTAINS OF NC INTO SE WV WILL ONLY STAY
STEADY OR FALL ONCE THE RAIN MOVES IN. BLF CURRENTLY 68...SO HIGH
MAY ACTUALLY OCCUR AT DAYBREAK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
AS OF 230 AM EDT THURSDAY...
AXIS OF VERY HEAVY RAIN INCLUDING EMBEDDED CONVECTION WILL PUSH EAST
ACROSS MUCH OF THE REGION THIS EVENING BEFORE EXITING THE
PIEDMONT BY EARLY FRIDAY. WITH THE 85H BOUNDARY SLOW TO EXIT
THE MOUNTAINS AND ANOTHER WEAK WAVE RIDING UP THE FRONT...EXPECT THE
BAND TO STALL FOR A BIT AND TRAIN UP ALONG THE BLUE RIDGE FROM SOUTH
TO NORTH ESPCLY DURING THE EARLY EVENING AS WEAK IMPULSES SHEAR
THROUGH THE PLUME OF VERY HIGH PWATS ALONG/EAST OF THE MOUNTAINS.
THIS SHOULD BE THE PERIOD OF HEAVIEST RAIN WITH ADDED AMOUNTS OF 1-
2+ INCHES WEST OF THE BLUE RIDGE ROUGHLY BEFORE MIDNIGHT...AND OUT
EAST MIDNIGHT THROUGH DAWN FRIDAY PENDING HOW FAST THE BAND
SHIFTS EAST LATE AT NIGHT UNDER THE PARALLEL UPPER FLOW. LATEST
GUIDANCE IS A BIT FASTER NOW IN SLIDING THE BAND EAST ONCE THE
SURFACE WAVE DEVELOPS TO THE SOUTH AND HEADS NE SO SPED UP MOVEMENT
OF THE HEAVY RAIN AFTER MIDNIGHT AND REDUCED TOTALS A BIT ACROSS THE
WEST LATE. HOWEVER LOCALLY HIGHER TOTALS ALSO LIKELY AS EARLY SE
UPSLOPE INTERACTS WITH THE STRONG LIFT ALONG THE SOUTHERN BLUE RIDGE
BEFORE THE FLOW VEERS OVERNIGHT. INCREASING 85H JET ALONG WITH
STRONG SHEAR COULD ALSO SUPPORT SOME EMBEDDED SEVERE POTENTIAL
ESPCLY DURING THU EVENING BUT IFFY LIKELY GIVEN SUCH A DEFINED AXIS
OF HEAVY RAINFALL AND LACK OF DEEP INSTABILITY AFTER THE LEADING
EDGE PUSHES ACROSS. THUS CONTINUED WITH CAT POPS THIS EVENING WITH A
FASTER EASTWARD SHIFT DURING THE OVERNIGHT WITH MOST HIGH POPS
CONFINED EAST OF THE BLUE RIDGE SHORTLY AFTER MIDNIGHT...AND
BASICALLY LOW CHANCES FAR EAST BY DAWN FRIDAY.
SURFACE FRONT FINALLY SHIFTS TO THE EAST FRIDAY AS WEAK LOW PRESSURE
HEADS TOWARD DELMARVA BY AFTERNOON. HOWEVER THE UPPER COLD POOL LAGS
BACK WITH THE COMBO OF SW FLOW ALOFT AND COOLING LIKELY ALLOWING FOR
A FEW ADDED -SHRA BANDS TO DEVELOP MAINLY WEST FRIDAY INTO FRIDAY
EVENING WITH WEAK DOWNSLOPE DRYING IN THE EAST. YET ANOTHER
SHORTWAVE WILL ROTATE UNDER THE 5H TROUGH BY SATURDAY WITH PERHAPS
ANOTHER UPSLOPE AIDED ROUND OF MOUNTAIN SHOWERS POSSIBLE INTO SAT
NIGHT SO KEPT IN LOW CHANCE POPS WEST.
OTRW THE PASSING FRONT TO START THE ONSET OF COOL ADVECTION LATER
TONIGHT WITH THE BRUNT OF THE 85H COOLING TAKING PLACE EARLY IN THE
WEEKEND. THIS LIKELY TO KEEP MOUNTAIN HIGHS IN THE 60S BOTH FRIDAY
AND SATURDAY WITH LOWS IN THE 40S AND PERHAPS SOME 30S DEEPER
VALLEYS LATE FRIDAY NIGHT AS SURFACE HIGH PRESSURE SETTLES
OVER THE WEST. EASTERN SECTIONS SHOULD BE ABLE TO SCRAPE IN THE
LOW/MID 70S FOR HIGHS BUT PERHAPS ONLY THAT WARM IN THE PIEDMONT BY
SATURDAY AFTERNOON.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1205 PM EDT WEDNESDAY...
CENTER OF THE STRONG UPPER TROUGH FOR MID/LATE MAY WILL PASS ACROSS
THE REGION SUNDAY AND THEN BEGIN TO SLOWLY LIFT OUT TO THE NE INTO
EARLY AND MID WEEK. THIS WILL RESULT IN AN EXTENDED PERIOD OF BELOW
NORMAL TEMPS THROUGH MUCH OF THE PERIOD...WITH CHILLY OVERNIGHT LOWS
ESPCLY IN THE MOUNTAIN VALLEYS EARLY NEXT WEEK WHEN SURFACE HIGH
PRESSURE SHOULD BE OVERHEAD. WITH THE COLD POOL ACROSS THE REGION
SUNDAY...MAY BE ENOUGH RESIDUAL MOISTURE TO HELP POP ISOLATED
AFTERNOON -SHRA MAINLY OVER THE NW SO KEPT IN A LOW POP THERE. OTRW
MODELS SHOW A PROLONGED PERIOD OF NW FLOW ALOFT ON THE BACK OF THE
DEPARTING 5H TROUGH WHILE UNDERCUTTING WITH WEAK HIGH PRESSURE IN
THE WAKE OF THIS SYSTEM. THIS SUPPORTS DRIER LOW LEVELS MONDAY INTO
TUESDAY WITH ANY IMPULSES ALOFT ONLY RESULTING IN AFTERNOON CU AND
ISOLATED -SHRA AT BEST. WARM ADVECTION PATTERN STARTS TO SHIFT EAST
BY MID WEEK WITH MODELS SHOWING A MORE DISTINCT WAVE SLIDING SE IN
ADVANCE OF A WARM FRONT ACROSS THE MIDWEST. EARLIER EC MOST
AGGRESSIVE WITH THIS FEATURE WITH POSSIBLE MCS BUT WAY TOO EARLY TO
TIME THIS ESPCLY GIVEN GUIDANCE DIFFERENCES. THUS INCLUDING A BIT
HIGHER POP ON DAY7 FOR NOW.
OTRW MAINLY PC WITH COMFORTABLE HIGHS IN THE 60S TO LOW 70S EARLY
ON...REBOUNDING TO MOSTLY 70S BY WED. LOWS MOSTLY IN THE 40S WITH
PERHAPS COLD ENOUGH 30S FOR SOME PATCHY DEEP VALLEY FROST
SUNDAY/MONDAY MORNINGS.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 740 AM EDT THURSDAY...
AVIATION FORECAST TO FOLLOW LATEST RAP AND NEAR TERM RADAR/SAT
TRENDS. WILL SEE A PERIOD OF MODERATE TO HEAVY RAIN OVER BCB AT
12Z...ENDING BY 13Z. STILL THINKING THE CIGS/VSBYS WILL STAY MVFR
OR LOWER TODAY WITH PERIODS OF MODERATE TO HEAVY SHOWERS WITH
EMBEDDED TSRA. MODELS FAVOR SLOW DOWN BUT LATEST TRENDS THIS
MORNING PER RADAR/SAT INDICATE THAT BLF COULD DRY OUT FASTER. WILL
HANG ONTO THE PREVIOUS FORECAST FROM 06Z BUT SPEED THINGS UP ABOUT
1-2 HRS. OVERNIGHT...THE EAST WILL STAY WITH SHOWERS WHILE WEST
WINDS DRY THINGS ACROSS THE WEST...ALTHOUGH LOW LVL MOISTURE WILL
LINGER INTO THE END OF THE TAF PERIOD.
STILL LOOKS LIKE POOR AVIATION CONDITIONS THRU MUCH OF THE TAF
PERIOD...WITH STRONG/SVR CONVECTION ALSO POSSIBLE ESPECIALLY EAST
OF THE MOUNTAINS THIS AFTERNOON.
EXTENDED AVIATION DISCUSSION...
EXPECT CONDITIONS TO IMPROVE AT ROA/LYH/DAN BY 12Z FRIDAY TO
VFR...AND THE MOUNTAINS SHOULD START TO SCOUR OUT DURING THE DAY
FRIDAY...BUT WITH UPPER LOW MOVING IN SOME SCT SHOWERS AND MVFR
CIGS POSSIBLE.
THIS LARGE UPPER LOW PRESSURE AREA WILL BECOME ANCHORED ACROSS
THE GREAT LAKES REGION THROUGH THE WEEKEND AND POSSIBLY INTO EARLY
NEXT WEEK. THIS WILL KEEP AN UNSTABLE/UNSETTLED WEATHER PATTERN IN
PLACE WITH BKN MVFR CIGS REMAINING POSSIBLE AT TIMES ALONG WITH
SCT -SHRA...ESPECIALLY ACROSS THE MOUNTAINS...IMPACTING
LWB/BLF/BCB THE MOST THROUGH THE WEEKEND.
&&
.HYDROLOGY...
AS OF 405 AM EDT THURSDAY...
FLASH FLOOD WATCH EXPANDED EAST TO COVER REST OF THE PIEDMONT.
STILL LOOKS LIKE 1-3 INCHES LIKELY FOR AREAL AVERAGE. AREAS ALONG
THE BLUE RIDGE ARE MORE THAN LIKELY GOING TO SEE ISOLATED AMOUNTS
OF 4-5" WITH RAINFALL RATES EXCEEDING 1.5" IN THUNDERSTORMS ALONG
WITH TRAINING OF ECHOES.
ALSO...GIVEN THIS AMOUNT OF RAINFALL...DO NOT BE SURPRISED TO SEE
A FEW MAIN STEM RIVER POINTS HEAD TOWARD MINOR FLOODING DEPENDING
ON HOW THE RAINFALL TOTALS PAN OUT AND WHICH BASINS GET THE MOST.
GEFS AND NAEFS RIVER ENSEMBLE FORECASTS STILL FAVORING THE
GREENBRIER TO GET HIT THE HARDEST POTENTIALLY GETTING TO MODERATE
FLOOD AT ALDERSON. MEANWHILE...THREAT OF MINOR FLOODING EXISTS
ALONG THE LOWER DAN AND ROANOKE RIVERS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR VAZ010>020-022>024-
032>035-043>047-058-059.
NC...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ001>006-018>020.
WV...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR WVZ042>045.
&&
$$
SYNOPSIS...WP
NEAR TERM...WP
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/RAB/WP
HYDROLOGY...WP
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
332 AM CDT SAT MAY 17 2014
.DISCUSSION...
331 AM CDT
AFTER THE INCREDIBLY LATE TASTE OF WINTER FOR PARTS OF THE AREA ON
FRIDAY...A FAIRLY QUIET WEATHER PATTERN IS SHAPING UP ALONG WITH A
NICE WARMING TREND INTO NEXT WEEK. THERE ARE NO SIGNIFICANT FORECAST
CONCERNS AFTER A WEEK AND A HALF OR SO OF ACTIVE WEATHER...THOUGH
THERE ARE SOME PERIODIC CHANCES FOR TSRA IN THE EXTENDED FORECAST
PERIOD. ADDITIONAL MINOR CONCERN IS WHICH DAYS ARE MOST FAVORED FOR
LAKE COOLING.
SHORT TERM...TODAY THROUGH MONDAY NIGHT
W/V IMAGERY THIS MORNING SHOWS ANOMALOUSLY DEEP UPPER TROUGH OVER
EASTERN NOAM. AGAIN SOME INCREDIBLY COLD 500 MB AND 850 MB TEMPS ON
THE 00Z RAOBS FOR THIS TIME OF YEAR...WITH -29C AT H5 AT KGRB AND
KILN AND -2C AT DVN AT H85. AT THE SURFACE...WEAK PRESSURE GRADIENT
ACROSS THE REGION AND SURFACE HIGH CENTERED OVER THE CENTRAL PLAINS.
TODAY AND TONIGHT...IT WILL BE A CHILLY START TO THE DAY WITH PARTLY
CLOUDY SKIES AND PATCHY TO AREAS OF FROST AND PATCHY GROUND FOG. THE
VERY COLD MIDLEVEL TEMPERATURES OVER THE AREA WILL SUPPORT A RAPID
BLOSSOMING OF FAIRLY HIGH-BASED STRATOCUMULUS BY MID TO LATE MORNING
OVER MUCH OF THE AREA AS LAPSE RATES STEEPEN. SOUNDINGS SHOW SOME
AVAILABLE CAPE DUE TO STEEP MIDLEVEL LAPSE RATES BUT LARGE T/TD
SPREADS AND OVERALL FORCING BEING FOCUSED MAINLY EAST OF THE AREA
THROW SOME DOUBT IN MUCH MORE THAN ISOLATED SHRA COVERAGE FROM BKN
STRATOCU DECK. THUS LOWERED POPS SOME INTO THE SLIGHT CHANCE RANGE.
WEAK WAA ALOFT DURING AFTN SUPPORTS HIGHS MOST AREAS REACHING NEAR
OR AROUND 60 DEGREES BASED ON 850/925 MB CLIMO. A WEAK LAKE BREEZE
MAY MAKE IT ONSHORE INTO CHICAGO AND PARTS OF NW IN SHORE DURING
AFTN AND KEEP THINGS SLIGHTLY COOLER THERE. DIURNALLY DRIVEN
STRATOCU SHOULD SCATTER OUT BY EARLY THIS EVENING...SETTING THE
STAGE FOR ANOTHER CHILLY NIGHT WITH LOWS IN UPPER 30S AND LOW 40S
OUTSIDE OF CHICAGO. SURFACE HIGH WILL BE SETTLING OVER EASTERN OH
VALLEY BY SUNDAY MORNING BUT WEAK GRADIENT WILL PREVENT SOUTHERLY
WINDS FROM INCREASING AND KEEPING TEMPS WARMER.
SUNDAY...SHAPING UP TO BE A GREAT DAY FOR OUTDOOR ACTIVITIES. OTHER
THAN SOME CIRRUS AND FAIR WEATHER CU...EXPECT PLENTY OF SUNSHINE AND
HIGHS JUST BELOW NORMAL INTO THE UPPER 60S. BUMPED UP TEMPERATURES
SLIGHTLY FROM PREVIOUS FORECAST ACCOUNTING FOR DRY AIR MASS BEING
CONDUCIVE TO MAXIMIZE HEATING BY SUN AS WELL AS CLOSER TO 925 MB
CLIMO. A WEAK LAKE BREEZE COULD PUSH ONTO PORTION OF SHORE BY LATE
AFTERNOON BUT LIKELY TOO LATE TO IMPACT HIGH TEMPERATURES.
MONDAY AND MONDAY NIGHT...WARM ADVECTION WILL CONTINUE TO INCREASE
DUE TO MIDLEVEL HEIGHT RISES. A FAIRLY DEEP UPPER TROUGH NEAR THE
WEST COAST WILL FORCE DOWNSTREAM RIDGING ACROSS THE MIDWEST. MID AND
HIGH CLOUDS ARE EXPECTED TO INCREASE FROM THE WEST DURING THE
AFTERNOON IN THE WARM ADVECTION PATTERN...BUT ACTUAL SHOWER ACTIVITY
LIKELY TO REMAIN WEST OF THE CWA. TEMPERATURES WILL WARM A FEW MORE
DEGREES TO AROUND 70/LOW 70S. THE EXCEPTION WILL BE THE IL LAKEFRONT
BASICALLY FROM DOWNTOWN CHICAGO AND NORTH WHICH WILL BE KEPT COOLER
IN THE LOWER 60S BY PERSISTENT SOUTHEAST COMPONENT TO THE WINDS.
GUIDANCE IS CONSISTENT ON A STRONG LOW LEVEL JET DEVELOPING MONDAY
NIGHT IN ADVANCE OF SURFACE LOW PRESSURE ACROSS THE PLAINS. NOSE OF
THE JET AND BEST CONVERGENCE SHOULD BE MAINLY NORTH OF CWA...BUT
CANNOT RULE OUT SOME SHRA DEVELOPMENT FOR NORTHERN 2/3 OF CWA. STEEP
LAPSE RATES FROM EML BEING ADVECTED OVER REGION...SO MENTIONED
SLIGHT CHANCE FOR TSRA.
LONG TERM...TUESDAY THROUGH FRIDAY...TO BE ISSUED SHORTLY.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SLIGHT CHANCE OF -SHRA THIS AFTERNOON.
//DISCUSSION...UPDATED 06Z...
THE DEEP UPPER TROUGH IS BEGINNING TO SHIFT EAST FROM THE
AREA...HOWEVER THE COLD AIR ALOFT WILL REMAIN INTO TODAY. THIS
LIKELY WILL SUPPORT BROKEN CUMULUS/STRATOCUMULUS THIS AFTERNOON
AND THE OUTSIDE POSSIBILITY OF A SHOWER. WINDS WILL BECOME MORE
WESTERLY BY LATE MORNING AND INCREASE IN SPEED TOWARD 10 KT. GARY
MAY EXPERIENCE A BRIEF SHIFT TO A NORTHEAST WIND THIS
AFTERNOON...BUT AT THIS TIME THAT LOOKS UNLIKELY. CLOUDS SHOULD
SCATTER LATE THIS AFTERNOON/THIS EVE.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH THAT IF ANY -SHRA OCCURS AT THE AIRFIELD IT WILL BE BRIEF.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY THROUGH MONDAY...VFR.
MONDAY THROUGH THURSDAY...GENERALLY VFR THOUGH SLIGHT CHANCE OF A
PERIOD OR TWO OF SHRA/TSRA DURING THE PERIOD.
MTF/IZZI
&&
.MARINE...
212 AM CDT
WEAK LOW PRESSURE WILL MOVE EASTWARD JUST NORTH OF THE GREAT
LAKES TODAY WHICH WILL ACT TO TIGHTEN THE PRESSURE
GRADIENT...NAMELY OVER THE NORTHERN TWO-THIRDS OR SO. DID END UP
INCREASING SPEEDS/GUSTS A FEW KNOTS BASED ON THIS. THE LOW
BASICALLY WASHES OUT THOUGH THE PRESSURE GRADIENT ACROSS THE LAKE
LOOKS TO HOLD ITS OWN THROUGH THE WEEKEND...AS HIGH PRESSURE
BECOMES STATIONARY OVER THE OHIO RIVER VALLEY AND LOW PRESSURE
DEVELOPS ACROSS THE HIGH PLAINS. THIS WILL SPELL CONTINUED
SOUTHERLY FLOW FOR THE LAKE ON MONDAY AND TUESDAY. THE LOW
PRESSURE ORIGINATING IN THE PLAINS LOOKS TO MOVE ACROSS THE
NORTHERN LAKES ON LATE TUESDAY OR EARLY WEDNESDAY AT THIS
TIME...WHICH WOULD FAVOR A COOL FRONT PASSAGE NEAR THAT
TIME...TURNING WINDS WESTERLY AND THEN NORTHWEST OR NORTH DURING
THE LATTER HALF OF THE WEEK. THIS WOULD LOOK TO RESULT IN AT LEAST
CLOSE TO SMALL CRAFT ADVISORY WAVE CONDITIONS FOR THE INDIANA AND
POSSIBLY ILLINOIS NEARSHORE AREAS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FROST ADVISORY...ILZ003-ILZ004-ILZ005-ILZ008-ILZ010-ILZ011-
ILZ012 UNTIL 7 AM SATURDAY.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
314 AM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 314 AM CDT Sat May 17 2014
SHORT TERM...Today through Monday
Upper low that has plagued the Great Lakes/Midwest for the past
several days will begin to lose its influence on the weather
today as it slowly lifts northeastward into Canada. Still plenty
of cold air aloft and weak cyclonic flow, so am expecting a robust
diurnal CU field and perhaps a few showers. HRRR is most
aggressive with developing precip furthest west into central
Illinois, while the NAM/GFS/ECMWF all tend to limit QPF to just
the far NE KILX CWA. Will follow the consensus here, keeping low
chance POPs for showers confined mainly along and northeast of a
Bloomington to Paris line in closer proximity to exiting upper
low. Given rising heights and increased sunshine, temps will be
quite a bit warmer than yesterday, with NAM forecast soundings
suggesting highs in the lower 60s.
After a clear/chilly night tonight with lows in the upper 30s and
lower 40s, ample sunshine will boost highs well into the 60s on
Sunday. Warming trend will continue into Monday, as upper wave
digs southward west of the Rockies, producing downstream ridging
across the central and eastern CONUS. As surface high pressure
shifts off to the east and low-level flow becomes more southerly,
high temps will return to near normal for this time of year in the
lower to middle 70s by Monday.
LONG TERM...Tuesday through Friday
A warmer and more unsettled pattern will develop in the extended.
A piece of energy from the western CONUS upper low will eject
eastward along the US/Canadian border, gradually flattening the
ridge across the Midwest. This will push a weak cold front
southward into central Illinois by the middle of next week. Model
solutions still vary on how far south this front will drop, but
with both the GFS and ECMWF advertising a strong 598dm 500mb high
developing along the Gulf Coast, do not think boundary will make
it too far south. As such, expect front to sag southward into
central Illinois on Wednesday, then become nearly stationary
through the end of the week. Given high heights and southerly
flow, high temperatures will reach the 80s on both Tuesday and
Wednesday, then will settle back into the 70s for Thursday and
Friday as the front tends to sink a bit further south toward the
Ohio River. Scattered showers and thunderstorms will develop in
the vicinity of the boundary beginning on Wednesday and persisting
through at least Thursday night. Latest runs of both the GFS and
ECMWF would suggest precip chances may need to be extended into
next weekend as front makes little or no southward progress.
Barnes
&&
.AVIATION...
ISSUED 1151 PM CDT Fri May 16 2014
VFR cigs prevail across most of central Illinois late this
evening, but the skies are tending to scatter out not too far
upstream. This clearing may combine with the light winds tonight
to allow fog to develop (which it very recently has at KPIA).
Model guidance does not really hit the fog potential at all, but
seeing as KPIA wend from 10SM to 1 3/4SM very rapidly, fog appears
to be a major concern anywhere clearing lasts for any significant
period of time. SC/CU should re-fire Saturday with diurnal heating,
but cigs only appear likely at KCMI and possibly KBMI & KDEC which
remain closer to the departing cold pool aloft. Expect winds to
remain rather light through the 06Z TAF valid period.
Bak
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY until 7 AM CDT this morning FOR ILZ027>031-036-
037-040>042-047>051.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
148 AM EDT SAT MAY 17 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY THROUGH THE FORECAST AREA TODAY.
THIS FRONT WILL THEN BECOME STATIONARY IN EASTERN MAINE. UPPER
LEVEL LOW PRESSURE WILL THEN MOVE OVERHEAD BY MONDAY AND REMAIN
NEAR THE AREA THROUGH THE WEEK RESULTING IN AN UNSETTLED WEATHER.
&&
.NEAR TERM /THROUGH TODAY/...
SHOWERS CONTINUE TO FORM AND RACE INTO MAINE OFF THE GULF OF MAINE
DURING THE EARLY MORNING HOURS. LARGER BAND OF CONVECTION WITH THE
ASSOCIATED COLD FRONT WILL MOVE EAST THIS MORNING...REACHING THE
PORTLAND AREA BY AROUND 09Z AND CLEARING THIS SAME REGION AROUND
14Z PER LATEST HRRR MODEL PROJECTS.
THEREFORE...THE HIGHEST POPS WILL BE IN DURING THE EARL TO MID
MORNING HOURS. NO SIGNIFICANT WIND SHIFT TIL LATER IN THE DAY...SO
CLEARING WILL BE CONFINED TO NEW HAMPSHIRE AND FAR WESTERN MAINE
LATER TODAY.
USED BLEND OF MESO MODEL DATA FOR AFTERNOON HIGH TEMPS.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM SUNDAY/...
CLEARING CONTINUES FROM WEST TO EAST TONIGHT INTO SUNDAY...WITH
THE MOST CLOUDINESS HANGING TOUGH IN THE UPSLOPE TERRAIN OF THE
WESTERN MOUNTAINS OF MAINE AND NORTHERN NEW HAMPSHIRE.
OTHERWISE...DESPITE PRESENCE OF UPPER LEVEL TROUGH ON
SUNDAY...FAVORABLE NORTHWEST WINDS WILL ALLOW FOR SOME SUNSHINE
AND MILD TEMPERATURES. THERE WILL BE A SLIGHT CHANCE FOR A SHOWER
WHERE MOISTURE WILL ACCOMPANY LIMITED DYNAMICS OVER EASTERNMOST
PORTIONS OF THE FORECAST AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AN UPPER CYCLONIC FLOW EARLY IN THE WEEK WILL ALLOW DIURNAL SCT
SHWRS TO DEVELOP EACH AFTN AS HEATING OCCURS. A WEAK RIDGE TRIES TO
BUILD OVER THE REGION BRIEFLY LATE TUE AND WED BUT STILL WITH A
CHC OF SHWRS. ANOTHER UPPER LOW WITH ITS CYCLONIC FLOW AND
INSTBLTY WILL ONCE AGAIN GET CARVED OUT OVER THE NORTHEAST LATER
IN THE WEEK ALLOWING MORE INSTBLTY SHWRS. TEMPS WILL BE NEAR
SEASONAL LEVELS THROUGH THE WEEK.
USED THE SUPERBLEND FOR POPS AND TEMPS.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...AREAS OF IFR AND LIFR CONDITIONS THIS
MORNING...FOLLOWED BY IMPROVING CONDITIONS TO VFR.
LONG TERM...MAINLY VFR CONDS BUT LOWERING TO MVFR IN SCT SHWRS.
&&
.MARINE...
SHORT TERM...SCA TO REMAIN IN PLACE FOR SEAS.
LONG TERM...WINDS/SEAS TO REMAIN BLO SCA CRITERIA.
&&
.FIRE WEATHER...RAIN AND WETTING CONDITIONS WILL KEEP FUELS MOIST.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
310 AM CDT SAT MAY 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CDT SAT MAY 17 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...NORTHWEST FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
REGION WITH EMBEDDED ENERGY STRETCHING FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS. WEAK HIGH PRESSURE ACROSS THE STATE
RESULTING IN LIGHT AND VARIABLE WINDS EARLY THIS MORNING. SCT-
BKN MID LEVEL CLOUDS NEAR THE MID LEVEL PVA FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS WITH MOSTLY CLEAR CONDITIONS CENTRAL
AND EAST.
WINDS WILL TAKE ON A MORE SOUTHERLY/WESTERLY COMPONENT ACROSS WEST
AND CENTRAL ND AS THE MORNING PROGRESSES WITH HIGH PRESSURE
DRIFTING TO OUR SOUTH. SFC RIDGE WILL REMAIN STRETCHED FROM
EASTERN SD BACK NORTHWEST ACROSS MY AREA THROUGH TODAY.
WHILE SOME MODELS TRY TO GENERATE QPF TODAY...HR MODELS SUCH AS
THE NESTED NAM AND RAP KEEP THINGS DRY. WITH THE SFC RIDGE IN
PLACE...LACK OF GOOD MID LEVEL ENERGY...AND THE UPPER JET PUSHING
OFF TO OUR SOUTH...DO NOT ANTICIPATE ANY PRECIPITATION SO WILL
REMAIN DRY. ALSO...CLOUD DECKS NEAR 8-10K FT AGL SHOULD PREVENT
ANY MEASURABLE PRECIPITATION OVER THE NEXT 24-36 HOURS EVEN IF A
MID LEVEL SHOWER DEVELOPS THIS SAT AFTERNOON/EVENING AS SOME OF
THE MODELS SUGGEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT SAT MAY 17 2014
SUNDAY SHOULD START DRY...BUT RAIN CHANCES WILL INCREASE ACROSS
WESTERN NORTH DAKOTA BY AFTERNOON AS A SURFACE TROUGH STRENGTHENS
ACROSS EASTERN MONTANA / WYOMING. IT APPEARS MUCH OF THE INITIAL
RAIN CHANCES WILL BE IN MONTANA AND WYOMING CLOSER TO THE SURFACE
FEATURE....BUT THE CHANCES SPREAD EAST LATE IN THE AFTERNOON AS
THE FIRST IN A SERIES OF UPPER WAVES MOVES INTO THE REGION.
INSTABILITY INCREASES SUNDAY AFTERNOON / EVENING IN WESTERN NORTH
DAKOTA WITH SBCAPE APPROACHING 1000 J/KG. DEEP LAYER SHEAR
APPROACHES 40-45 KTS...SO THINK AT LEAST A FEW STRONG STORMS ARE
POSSIBLE AND INCLUDED THE MENTION IN THE HAZARDOUS WEATHER
OUTLOOK. THIS ALSO LINES UP WELL WITH THE SPC DAY 2 COMBINED
SEVERE OUTLOOK PROBABILITIES.
THE THUNDERSTORM CHANCES SPREAD ACROSS WESTERN AND CENTRAL NORTH
DAKOTA SUNDAY NIGHT AS A 50 KT LOW LEVEL JET LIFTS INTO THE
REGION. THE MODELS ARE IN GOOD AGREEMENT REGARDING THE RAIN
CHANCES SUNDAY NIGHT...SO WILL KEEP POPS IN THE LIKELY CATEGORY.
MODEL UNCERTAINTY INCREASES ON MONDAY WITH DIFFERING SOLUTIONS
REGARDING THE PROGRESSION OF THE SURFACE LOW. OVERALL...IT APPEARS
THE MODELS ARE FAVORING LESS NEW SHOWER/THUNDERSTORM DEVELOPMENT
MONDAY AFTERNOON...AND CONFINE THE BEST CHANCES TO THE EASTERN
PORTION OF THE FORECAST AREA AS THE LOW MOVES THROUGH.
THE REMAINDER OF THE EXTENDED PERIOD WILL FEATURE PERIODIC WAVES
MOVING THROUGH WEAK RIDGING ACROSS THE NORTHERN PLAINS. THE LATEST
GFS AND ECMWF SHOW A BIT MORE INSTABILITY AVAILABLE THROUGH THE
WEEK...SO HAVE ADDED THUNDERSTORM CHANCES WHERE APPROPRIATE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 309 AM CDT SAT MAY 17 2014
VFR CONDITIONS ARE FORECAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA FOR THE 06Z TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NH
LONG TERM...CK
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
106 AM CDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 106 AM CDT SAT MAY 17 2014
WEAK SURFACE BOUNDARY REMAINS ACROSS WEST INTO SOUTH CENTRAL NORTH
DAKOTA. OVERALL WINDS LIGHT TO VARIABLE EARLY THIS MORNING.
EMBEDDED ENERGY MOVING FROM EASTERN MONTANA THROUGH THE WESTERN
DAKOTAS CONTINUES TO GENERATE MID LEVEL CLOUDS WEST. MOSTLY CLEAR
CONDITIONS EAST.
MAIN UPDATE WAS TO BEEF UP CLOUD COVER ACROSS THE WEST...AND
ADJUST TEMPERATURES BASED ON LATEST OBSERVATIONS.
WHILE SOME MODELS GENERATE QPF TODAY...HR MODELS SUCH AS THE
NESTED NAM AND RAP KEEP THINGS DRY. HARD TO DISAGREE AS THE SAME
MODELS (GFS/NAM/ECMWF) THAT ARE GENERATING QPF FOR SATURDAY ARE
ALSO SAYING THERE SHOULD BE PRECIPITATION OVER MY WESTERN COUNTIES
RIGHT NOW (THERE IS NOT). THUS REMOVED ALL WEATHER MENTION FOR
SATURDAY WITH NO CLEAR SFC BOUNDARY IN PLACE...LACK OF GOOD MID
LEVEL ENERGY...AND THE UPPER JET PUSHING OFF TO OUR SOUTH. CLOUD
DECKS NEAR 8-10K FT AGL SHOULD PREVENT ANY MEASURABLE
PRECIPITATION OVER THE NEXT 24-36 HOURS EVEN IF A MID LEVEL SHOWER
DEVELOPS SAT AFTERNOON/EVENING AS SOME OF THE MODELS SUGGEST.
UPDATE ISSUED AT 947 PM CDT FRI MAY 16 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. PER
COORDINATION WITH WFO GRAND FORKS AND ABERDEEN...DID NOT ISSUE A
FROST ADVISORY FOR THE CENTRAL TONIGHT. DESPITE CLEAR
SKIES...LIGHT WINDS AND DEW POINTS IN THE 20S THIS EVENING...THE
OVERALL AIRMASS IS SLIGHTLY WARMER COMPARED TO LAST NIGHT...AND
RESIDENCE TIME IN TEMPERATURES BETWEEN 33 AND 36 WILL BE BRIEF.
DID MAINTAIN THE PATCHY FROST MENTION AND INCLUDED IN THE HWO.
UPDATE ISSUED AT 555 PM CDT FRI MAY 16 2014
QUICK UPDATE TO EXPAND THE PATCHY FROST MENTION FURTHER WEST INTO
THE HIGHWAY 83 CORRIDOR WITH DEWPOINTS IN THE 20S LATE THIS
AFTERNOON...AND CLEAR SKIES AND LIGHT WINDS FORECAST THROUGH THE
NIGHT. WILL MONITOR HOW QUICKLY TEMPERATURES FALL NEARING TO
SHORTLY AFTER SUNSET SHOULD A FROST ADVISORY BECOME NECESSARY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 254 PM CDT FRI MAY 16 2014
THE MAIN FORECAST ISSUES IN THE SHORT TERM PERIOD ARE RAIN
CHANCES/COVERAGE THROUGH THIS EVENING AND AGAIN SATURDAY...AS WELL
AS TEMPERATURES/FROST POTENTIAL TONIGHT.
LATEST RADAR TRENDS INDICATE A FEW SHOWERS STARTING TO DEVELOP
ACROSS THE NORTHWEST NEAR TIOGA...AND IN THE SOUTH CENTRAL OVER
PARTS OF HETTINGER/GRANT COUNTIES. OVERALL COVERAGE OF SHOWERS AND
POSSIBLY AN ISOLATED THUNDERSTORM SHOULD REMAIN RELATIVELY LIMITED
THROUGH EARLY EVENING. OVERNIGHT...THE MOST FAVORABLE COOLING
CONDITIONS WILL EXIST FROM THE JAMES RIVER VALLEY INTO THE TURTLE
MOUNTAINS AREA...WHERE PATCHY FROST IS EXPECTED WITH LOWS IN THE
MID 30S. WILL MENTION FROST IN FORECAST GRIDS...BUT HOLD OFF
ISSUING HEADLINES DUE TO THE RATHER LIMITED AREAL COVERAGE AND DURATION.
ON SATURDAY...EXPECT THE WARMING TREND TO CONTINUE. A WEAK SHORT
WAVE TROUGH IS FORECAST TO OVER TOP THE UPPER RIDGE AND MOVE THROUGH
THE REGION. MORE SCATTERED SHOWERS ARE POSSIBLE...ESPECIALLY
CENTRAL THROUGH SOUTHWEST. LIMITED ELEVATED INSTABILITY SHOULD BE
IN PLACE ACROSS THE FAR SOUTHWEST IN THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM CDT FRI MAY 16 2014
MUCH OF EXTENDED PERIOD WILL SEE A LONGWAVE TROUGH PERSIST ACROSS
WESTERN CONUS LEAVING NORTHERN PLAINS UNDER WEAK RIDGING OR
SOUTHWEST FLOW. MODELS IN GOOD AGREEMENT DEPICTING SHORTWAVE IN
SOUTHWEST FLOW APPROACH THE NORTHERN PLAINS ON SUNDAY. HEIGHT
FALLS AHEAD OF THIS SHORTWAVE ALONG WITH INCREASING MID-LEVEL
LAPSE RATES AND CAPE AROUND 500 J/KG ACROSS SOUTHWEST ND WILL
SUPPORT INCREASING CHANCES OF THUNDERSTORMS. SPC HAS HIGHLIGHTED
THE AREA JUST SOUTHWEST OF THE STATE WITH A 5% SEVERE RISK SUNDAY.
PRECIP SHOULD SPREAD WEST TO EAST SUNDAY AFTERNOON AND NIGHT AS
SURFACE LOW REACHES CENTRAL ND BY 12Z MON. CONVECTIVE THREAT WILL
CONTINUE MONDAY WITH STRONG/SEVERE STORMS POSSIBLE...MAINLY
ACROSS THE EASTERN HALF OF THE STATE AHEAD OF THE COLD FRONT WHERE
GFS CAPE VALUES APPROACH 1000 J/KG ALONG WITH 0-6KM SHEAR VALUES
NEAR 40KTS. QPF AMOUNTS FROM THIS SYSTEM WILL RANGE FROM .25
INCHES MOST AREAS TO AROUND .50 INCHES WEST. THE REMAINDER OF THE
WEEK SHOULD BE RELATIVELY QUIET WITH LOW CHANCES OF PRECIPITATION
CONTINUING AS REGION SITS UNDER WEAK RIDGE. TEMPS WILL RUN CLOSE
TO NORMAL...WITH HIGHS IN THE 60S AND LOW 70S WITH NIGHTTIME TEMPS
DROPPING INTO THE 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 106 AM CDT SAT MAY 17 2014
VFR CONDITIONS ARE FORECAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA FOR THE 06Z TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
LONG TERM...JNS
AVIATION...NH
Area Forecast Discussion
National Weather Service Lincoln IL
1048 AM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sat May 17 2014
A little bit of a cyclonic turn to the winds still as the upper
trof slowly moves out of the Midwest. But between that and plenty
of moisture at llvls, cu field filling in on sat imagery this
morning. Some of those cu starting to get a bit heavy and showing
up on radar. There is a moderate amount of dry air to help cut
down overall precip accumulations, but activity is likely to be
very isolated anyway. Have expanded the iso mention, but no large
scale updates are anticipated at this time.
HJS
&&
.AVIATION...
ISSUED 640 AM CDT Sat May 17 2014
Residual moisture from the rain last evening and heavy dew/patchy
frost was creating shallow ground fog in spots early this morning,
especially at KPIA where the visibility has varied between 1/2 and
10 SM. Will go with MIFG at KPIA until 14z before plenty of sun will
eventually warm up the ground and help dissipate the fog. KCMI
could be similar, although it appears that MVFR visibility will
prevail there.
From mid-morning and beyond, the moisture profiles on the RAP and
the cloud base forecasts on the HRRR indicate the development of
additional high based CU around 5-7 kft ahead of another in a
series of shortwave troughs rotating toward the base of the upper
trough axis in Indiana.
There could be just enough instability for a few showers to
develop in east central IL, but the coverage and probability of
occurrence precludes a mention of VCSH in the TAFs for KBMI and
KCMI.
High pressure and rapidly increasing stability this evening will
give us a clear sky and very light wind from just before sunset
through daybreak Sunday.
Miller
&&
.PREV DISCUSSION...
ISSUED 314 AM CDT Sat May 17 2014
SHORT TERM...Today through Monday
Upper low that has plagued the Great Lakes/Midwest for the past
several days will begin to lose its influence on the weather
today as it slowly lifts northeastward into Canada. Still plenty
of cold air aloft and weak cyclonic flow, so am expecting a robust
diurnal CU field and perhaps a few showers. HRRR is most
aggressive with developing precip furthest west into central
Illinois, while the NAM/GFS/ECMWF all tend to limit QPF to just
the far NE KILX CWA. Will follow the consensus here, keeping low
chance POPs for showers confined mainly along and northeast of a
Bloomington to Paris line in closer proximity to exiting upper
low. Given rising heights and increased sunshine, temps will be
quite a bit warmer than yesterday, with NAM forecast soundings
suggesting highs in the lower 60s.
After a clear/chilly night tonight with lows in the upper 30s and
lower 40s, ample sunshine will boost highs well into the 60s on
Sunday. Warming trend will continue into Monday, as upper wave
digs southward west of the Rockies, producing downstream ridging
across the central and eastern CONUS. As surface high pressure
shifts off to the east and low-level flow becomes more southerly,
high temps will return to near normal for this time of year in the
lower to middle 70s by Monday.
LONG TERM...Tuesday through Friday
A warmer and more unsettled pattern will develop in the extended.
A piece of energy from the western CONUS upper low will eject
eastward along the US/Canadian border, gradually flattening the
ridge across the Midwest. This will push a weak cold front
southward into central Illinois by the middle of next week. Model
solutions still vary on how far south this front will drop, but
with both the GFS and ECMWF advertising a strong 598dm 500mb high
developing along the Gulf Coast, do not think boundary will make
it too far south. As such, expect front to sag southward into
central Illinois on Wednesday, then become nearly stationary
through the end of the week. Given high heights and southerly
flow, high temperatures will reach the 80s on both Tuesday and
Wednesday, then will settle back into the 70s for Thursday and
Friday as the front tends to sink a bit further south toward the
Ohio River. Scattered showers and thunderstorms will develop in
the vicinity of the boundary beginning on Wednesday and persisting
through at least Thursday night. Latest runs of both the GFS and
ECMWF would suggest precip chances may need to be extended into
next weekend as front makes little or no southward progress.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
904 AM CDT SAT MAY 17 2014
.DISCUSSION...
331 AM CDT
AFTER THE INCREDIBLY LATE TASTE OF WINTER FOR PARTS OF THE AREA ON
FRIDAY...A FAIRLY QUIET WEATHER PATTERN IS SHAPING UP ALONG WITH A
NICE WARMING TREND INTO NEXT WEEK. THERE ARE NO SIGNIFICANT FORECAST
CONCERNS AFTER A WEEK AND A HALF OR SO OF ACTIVE WEATHER...THOUGH
THERE ARE SOME PERIODIC CHANCES FOR TSRA IN THE EXTENDED FORECAST
PERIOD. ADDITIONAL MINOR CONCERN IS WHICH DAYS ARE MOST FAVORED FOR
LAKE COOLING.
SHORT TERM...TODAY THROUGH MONDAY NIGHT
W/V IMAGERY THIS MORNING SHOWS ANOMALOUSLY DEEP UPPER TROUGH OVER
EASTERN NOAM. AGAIN SOME INCREDIBLY COLD 500 MB AND 850 MB TEMPS ON
THE 00Z RAOBS FOR THIS TIME OF YEAR...WITH -29C AT H5 AT KGRB AND
KILN AND -2C AT DVN AT H85. AT THE SURFACE...WEAK PRESSURE GRADIENT
ACROSS THE REGION AND SURFACE HIGH CENTERED OVER THE CENTRAL PLAINS.
TODAY AND TONIGHT...IT WILL BE A CHILLY START TO THE DAY WITH PARTLY
CLOUDY SKIES AND PATCHY TO AREAS OF FROST AND PATCHY GROUND FOG. THE
VERY COLD MIDLEVEL TEMPERATURES OVER THE AREA WILL SUPPORT A RAPID
BLOSSOMING OF FAIRLY HIGH-BASED STRATOCUMULUS BY MID TO LATE MORNING
OVER MUCH OF THE AREA AS LAPSE RATES STEEPEN. SOUNDINGS SHOW SOME
AVAILABLE CAPE DUE TO STEEP MIDLEVEL LAPSE RATES BUT LARGE T/TD
SPREADS AND OVERALL FORCING BEING FOCUSED MAINLY EAST OF THE AREA
THROW SOME DOUBT IN MUCH MORE THAN ISOLATED SHRA COVERAGE FROM BKN
STRATOCU DECK. THUS LOWERED POPS SOME INTO THE SLIGHT CHANCE RANGE.
WEAK WAA ALOFT DURING AFTN SUPPORTS HIGHS MOST AREAS REACHING NEAR
OR AROUND 60 DEGREES BASED ON 850/925 MB CLIMO. A WEAK LAKE BREEZE
MAY MAKE IT ONSHORE INTO CHICAGO AND PARTS OF NW IN SHORE DURING
AFTN AND KEEP THINGS SLIGHTLY COOLER THERE. DIURNALLY DRIVEN
STRATOCU SHOULD SCATTER OUT BY EARLY THIS EVENING...SETTING THE
STAGE FOR ANOTHER CHILLY NIGHT WITH LOWS IN UPPER 30S AND LOW 40S
OUTSIDE OF CHICAGO. SURFACE HIGH WILL BE SETTLING OVER EASTERN OH
VALLEY BY SUNDAY MORNING BUT WEAK GRADIENT WILL PREVENT SOUTHERLY
WINDS FROM INCREASING AND KEEPING TEMPS WARMER.
SUNDAY...SHAPING UP TO BE A GREAT DAY FOR OUTDOOR ACTIVITIES. OTHER
THAN SOME CIRRUS AND FAIR WEATHER CU...EXPECT PLENTY OF SUNSHINE AND
HIGHS JUST BELOW NORMAL INTO THE UPPER 60S. BUMPED UP TEMPERATURES
SLIGHTLY FROM PREVIOUS FORECAST ACCOUNTING FOR DRY AIR MASS BEING
CONDUCIVE TO MAXIMIZE HEATING BY SUN AS WELL AS CLOSER TO 925 MB
CLIMO. A WEAK LAKE BREEZE COULD PUSH ONTO PORTION OF SHORE BY LATE
AFTERNOON BUT LIKELY TOO LATE TO IMPACT HIGH TEMPERATURES.
MONDAY AND MONDAY NIGHT...WARM ADVECTION WILL CONTINUE TO INCREASE
DUE TO MIDLEVEL HEIGHT RISES. A FAIRLY DEEP UPPER TROUGH NEAR THE
WEST COAST WILL FORCE DOWNSTREAM RIDGING ACROSS THE MIDWEST. MID AND
HIGH CLOUDS ARE EXPECTED TO INCREASE FROM THE WEST DURING THE
AFTERNOON IN THE WARM ADVECTION PATTERN...BUT ACTUAL SHOWER ACTIVITY
LIKELY TO REMAIN WEST OF THE CWA. TEMPERATURES WILL WARM A FEW MORE
DEGREES TO AROUND 70/LOW 70S. THE EXCEPTION WILL BE THE IL LAKEFRONT
BASICALLY FROM DOWNTOWN CHICAGO AND NORTH WHICH WILL BE KEPT COOLER
IN THE LOWER 60S BY PERSISTENT SOUTHEAST COMPONENT TO THE WINDS.
GUIDANCE IS CONSISTENT ON A STRONG LOW LEVEL JET DEVELOPING MONDAY
NIGHT IN ADVANCE OF SURFACE LOW PRESSURE ACROSS THE PLAINS. NOSE OF
THE JET AND BEST CONVERGENCE SHOULD BE MAINLY NORTH OF CWA...BUT
CANNOT RULE OUT SOME SHRA DEVELOPMENT FOR NORTHERN 2/3 OF CWA. STEEP
LAPSE RATES FROM EML BEING ADVECTED OVER REGION...SO MENTIONED
SLIGHT CHANCE FOR TSRA.
LONG TERM...TUESDAY THROUGH FRIDAY...
850/925 MB TEMPS ARE PROGGED TO SOAR INTO THE MID TO HIGH TEENS
ON TUESDAY...SO MANY AREAS HAVE A GOOD SHOT TO REACH OR EXCEED 80
BY A FEW DEGREES EVEN WITH POTENTIAL FOR ONLY PARTIAL SUNSHINE.
FAR NORTHEAST IL COULD STILL BE KEPT COOLER BY SLIGHT SOUTHEAST
COMPONENT TO WIND THERE. FORECAST SOUNDINGS SHOW THAT ATMOSPHERE
COULD REMAIN LARGELY CAPPED TO CONVECTION UNLESS A MIDLEVEL WAVE
IS STRONG ENOUGH TO BREAK CAP. HOWEVER FOR NOW MAINTAINED GUIDANCE
BLEND SLIGHT TO LOW CHANCE POPS.
BETTER CHANCE FOR CONVECTION OVER NORTHERN HALF OF CWA WILL COME
WITH APPROACH OF SURFACE COLD FRONT TUESDAY EVENING NIGHT. GUIDANCE
IN DECENT AGREEMENT IN FRONTAL BOUNDARY ONLY SLOWLY PROGRESSING
SOUTH WEDNESDAY AND THURSDAY AND ELEVATED FRONT LAGGING EVEN MORE.
THUS THERE COULD BE SOME CONVECTIVE ACTIVITY INTO SOUTHERN HALF TO
THIRD OF CWA DURING THAT PERIOD...WITH BETTER CHANCE IN FAR SOUTH
CLOSER TO FRONTAL BOUNDARY. WEDNESDAY WILL BE ANOTHER WARM DAY FOR
MOST OF THE AREA WITH HIGHS IN UPPER 70S TO LOW 80S INLAND. THIS IS
DESPITE THE COLD FRONT LIKELY TO HAVE PUSHED INTO SOUTHERN CWA.
THE EXCEPTION TO THE WARMTH WILL BE THE LAKEFRONT AS A LAKE BREEZE
WILL DEVELOP EARLY AND KEEP TEMPERATURES 10 OR MORE DEGREES
COOLER. THURSDAY WILL BE SIMILAR BUT LIKELY NOT QUITE AS WARM
INLAND. NEXT FRIDAY IT APPEARS THAT SURFACE HIGH WILL BE OVER
WESTERN LAKES...WHICH SHOULD FAVOR DRY FORECAST. TEMPERATURES
SHOULD BE NEAR TO SLIGHTLY BELOW SEASONABLE INLAND BUT AGAIN
SEVERAL DEGREES COOLER NEAR THE LAKE.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SLIGHT CHANCE OF -SHRA THIS AFTERNOON.
//DISCUSSION...UPDATED 12Z...
WHILE THE UPPER LOW THAT BROUGHT SNOW TO SOME OF THE AREA
AIRPORTS YESTERDAY HAS NOW SHIFTED EAST...COLD TEMPERATURES ALOFT
WILL SUPPORT THE BLOSSOMING OF CUMULUS/STRATOCUMULUS LATE THIS
MORNING INTO AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE...BUT
COVERAGE SHOULD BE MUCH LESS THAN FRIDAY AFTERNOON. LIGHT
SOUTHWEST WINDS WILL INCREASE IN SPEED AS MIXING ENSUES AND SHOULD
BE ENOUGH TO PREVENT A LAKE BREEZE FROM REACHING MOST OF THE
CHICAGOLAND TAF SITES. THE EXCEPTION WOULD BE GARY WHERE WINDS MAY
BRIEFLY TURN NORTH/NORTHEAST DURING THE AFTERNOON HOURS. WINDS
WILL LIGHTEN SOME TONIGHT BEFORE INCREASING SUNDAY MORNING FROM
THE SOUTHWEST. ALL IN ALL...NO IMPACTS TO AVIATION EXPECTED.
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH THAT IF ANY -SHRA OCCURS AT THE AIRFIELD IT WILL BE BRIEF.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA DURING THE NIGHT.
TUESDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA.
WEDNESDAY...EAST FLOW.
THURSDAY...EAST FLOW. SLIGHT CHANCE OF TSRA DURING THE NIGHT.
FRIDAY...EAST FLOW.
MTF
&&
.MARINE...
212 AM CDT
WEAK LOW PRESSURE WILL MOVE EASTWARD JUST NORTH OF THE GREAT
LAKES TODAY WHICH WILL ACT TO TIGHTEN THE PRESSURE
GRADIENT...NAMELY OVER THE NORTHERN TWO-THIRDS OR SO. DID END UP
INCREASING SPEEDS/GUSTS A FEW KNOTS BASED ON THIS. THE LOW
BASICALLY WASHES OUT THOUGH THE PRESSURE GRADIENT ACROSS THE LAKE
LOOKS TO HOLD ITS OWN THROUGH THE WEEKEND...AS HIGH PRESSURE
BECOMES STATIONARY OVER THE OHIO RIVER VALLEY AND LOW PRESSURE
DEVELOPS ACROSS THE HIGH PLAINS. THIS WILL SPELL CONTINUED
SOUTHERLY FLOW FOR THE LAKE ON MONDAY AND TUESDAY. THE LOW
PRESSURE ORIGINATING IN THE PLAINS LOOKS TO MOVE ACROSS THE
NORTHERN LAKES ON LATE TUESDAY OR EARLY WEDNESDAY...WHICH WOULD
FAVOR A COOL FRONT PASSAGE NEAR THAT TIME...TURNING WINDS WESTERLY
AND THEN NORTHWEST OR NORTH DURING THE LATTER HALF OF THE WEEK.
THIS WOULD LOOK TO RESULT IN AT LEAST CLOSE TO SMALL CRAFT
ADVISORY WAVE CONDITIONS FOR THE INDIANA AND POSSIBLY ILLINOIS
NEARSHORE AREAS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
640 AM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 314 AM CDT Sat May 17 2014
SHORT TERM...Today through Monday
Upper low that has plagued the Great Lakes/Midwest for the past
several days will begin to lose its influence on the weather
today as it slowly lifts northeastward into Canada. Still plenty
of cold air aloft and weak cyclonic flow, so am expecting a robust
diurnal CU field and perhaps a few showers. HRRR is most
aggressive with developing precip furthest west into central
Illinois, while the NAM/GFS/ECMWF all tend to limit QPF to just
the far NE KILX CWA. Will follow the consensus here, keeping low
chance POPs for showers confined mainly along and northeast of a
Bloomington to Paris line in closer proximity to exiting upper
low. Given rising heights and increased sunshine, temps will be
quite a bit warmer than yesterday, with NAM forecast soundings
suggesting highs in the lower 60s.
After a clear/chilly night tonight with lows in the upper 30s and
lower 40s, ample sunshine will boost highs well into the 60s on
Sunday. Warming trend will continue into Monday, as upper wave
digs southward west of the Rockies, producing downstream ridging
across the central and eastern CONUS. As surface high pressure
shifts off to the east and low-level flow becomes more southerly,
high temps will return to near normal for this time of year in the
lower to middle 70s by Monday.
LONG TERM...Tuesday through Friday
A warmer and more unsettled pattern will develop in the extended.
A piece of energy from the western CONUS upper low will eject
eastward along the US/Canadian border, gradually flattening the
ridge across the Midwest. This will push a weak cold front
southward into central Illinois by the middle of next week. Model
solutions still vary on how far south this front will drop, but
with both the GFS and ECMWF advertising a strong 598dm 500mb high
developing along the Gulf Coast, do not think boundary will make
it too far south. As such, expect front to sag southward into
central Illinois on Wednesday, then become nearly stationary
through the end of the week. Given high heights and southerly
flow, high temperatures will reach the 80s on both Tuesday and
Wednesday, then will settle back into the 70s for Thursday and
Friday as the front tends to sink a bit further south toward the
Ohio River. Scattered showers and thunderstorms will develop in
the vicinity of the boundary beginning on Wednesday and persisting
through at least Thursday night. Latest runs of both the GFS and
ECMWF would suggest precip chances may need to be extended into
next weekend as front makes little or no southward progress.
&&
.AVIATION...
ISSUED 640 AM CDT Sat May 17 2014
Residual moisture from the rain last evening and heavy dew/patchy
frost was creating shallow ground fog in spots early this morning,
especially at KPIA where the visibility has varied between 1/2 and
10 SM. Will go with MIFG at KPIA until 14z before plenty of sun will
eventually warm up the ground and help dissipate the fog. KCMI
could be similar, although it appears that MVFR visibility will
prevail there.
From mid-morning and beyond, the moisture profiles on the RAP and
the cloud base forecasts on the HRRR indicate the development of
additional high based CU around 5-7 kft ahead of another in a
series of shortwave troughs rotating toward the base of the upper
trough axis in Indiana.
There could be just enough instability for a few showers to
develop in east central IL, but the coverage and probability of
occurrence precludes a mention of VCSH in the TAFs for KBMI and
KCMI.
High pressure and rapidly increasing stability this evening will
give us a clear sky and very light wind from just before sunset
through daybreak Sunday.
Miller
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY until 7 AM CDT this morning FOR ILZ027>031-036-
037-040>042-047>051.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
1017 AM EDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 1017 AM EDT SAT MAY 17 2014
UPDATED NDFD AND ASSOCIATED FORECAST PRODUCTS BASED ON LATEST
ANALYSIS AND TRENDS. WILL CONTINUE TO CARRY ISOLATED SHOWERS IN THE
FAR SOUTH THIS AFTERNOON AS STILL SEEING SOME RADAR RETURNS OVER FAR
SOUTH CENTRAL KY. THERE HAS BEEN 0.01 INCH AT THE TODD COUNTY
MESONET SITE THIS MORNING...SO VERY LOW END MEASURABLE RAIN IS
POSSIBLE. HAVE ALSO ADDED ISOLATED SHOWERS OVER THE FAR NORTHERN
PART OF THE FORECAST AREA...MAINLY JUST FLEMING COUNTY. MORNING SOUNDINGS
SHOW COLDEST MID LEVEL TEMPERATURES OVER OH INTO FAR NORTHERN
KY...AND ENOUGH INSTABILITY EXISTS FOR SHOWERS. SCATTERED SHOWERS
ALREADY ON RADAR OVER SOUTHERN OH...AND IT IS POSSIBLE THAT SOME
SHOWERS MAY CLIP OUR FORECAST AREA. THIS IDEA IS SUPPORTED BY THE
LATEST HRRR GUIDANCE. OTHER UPDATED ELEMENTS INCLUDED SKY COVER...AS
THE CLOUD COVER WILL HOLD LONGER IN THE SOUTH...AND MAY BE A LITTLE
MORE EXTENSIVE IN THE NORTH WHERE IT WILL BE MORE CONVECTIVE IN
NATURE. THE CENTRAL PART OF THE FORECAST AREA SHOULD HAVE THE MOST
SUNSHINE THIS AFTERNOON. FINALLY MADE SOME MINOR ADJUSTMENTS TO
TEMPERATURES DUE TO THE SKY COVER ADJUSTMENTS.
UPDATE ISSUED AT 752 AM EDT SAT MAY 17 2014
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND SKY COVER
ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS. THICKER MID-LEVEL
CLOUD COVER HAS EDGED A BIT MORE NORTH EARLY THIS MORNING...ALTHOUGH
THE NORTHERN PERIPHERY OF THE SHIELD SHOULD BURN OFF SOMEWHAT LATER
THIS MORNING. OTHERWISE...THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 335 AM EDT SAT MAY 17 2014
THE LATEST SURFACE MAP FEATURES BROAD HIGH PRESSURE SPRAWLED ACROSS
THE CENTRAL PLAINS...WITH ANOTHER HIGH CENTERED ACROSS THE DEEP
SOUTH. LOW PRESSURE REMAINS POISED ACROSS NM/TX...WITH AN INVERTED
TROUGH NOSING IN THROUGH THE TENNESSEE VALLEY...SEPARATING THE
AFOREMENTIONED TWO HIGH PRESSURE AREAS. ALOFT...AN UPPER LEVEL LOW
IS SPIRALING ACROSS ONTARIO...LEAVING THE OHIO VALLEY AND GREAT
LAKES REGIONS IN AN UNSEASONABLY COOL AIR MASS. TEMPERATURES ACROSS
EASTERN KENTUCKY ARE CURRENTLY RANGING FROM 36 TO 41 DEGREES...WITH
AREAS OF DENSE VALLEY FOG SHOWING UP NICELY ON SATELLITE.
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH
CYCLONIC FLOW GRADUALLY EASING UP ACROSS THE OHIO AND TENNESSEE
VALLEYS...AS THE CANADIAN UPPER LOW FILLS AND THE ASSOCIATED TROUGH
SHIFTS EAST...WITH UPPER LEVEL RIDGING WORKING IN FROM THE WEST.
A SHORT WAVE TROUGH CURRENTLY MOVING THROUGH MISSOURI WILL MOVE INTO
THE TENNESSEE VALLEY TODAY...PROVIDING A FOCUS FOR SOME SHOWER
ACTIVITY GENERALLY SOUTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80
CORRIDORS. THIS WAVE IS MUCH TAMER COMPARED TO FRIDAY...SO ONLY
ISOLATED COVERAGE IS EXPECTED. FURTHER NORTH...EXPECTING MAINLY JUST
A GOOD CUMULUS FIELD TO BUILD IN...WITH PERHAPS A STRAY SPRINKLE OR
LIGHT SHOWER POSSIBLE DURING PEAK HEATING. HIGHS WILL AVERAGE A GOOD
15 DEGREES BELOW NORMAL...GENERALLY AROUND THE 60 DEGREE MARK.
SKIES WILL BE SLOW TO CLEAR IN THE SOUTH TONIGHT...LIKELY KEEPING THE
PATCHY FROST POTENTIAL IN CHECK. FURTHER NORTH THERE WILL BE BETTER
POTENTIAL FOR SOME PATCHY FROST...AS TEMPERATURES LOOK TO DROP INTO
THE MID 30S IN THE COLDEST SPOTS ONCE AGAIN...WITH MORE SUSTAINED
CLEARING TAKING PLACE. FOG WILL ALSO BE PREVALENT ONCE AGAIN AS WELL.
SUNDAY WILL BE DRY WITH MORE SUNSHINE...AS THE TROUGH SHIFTS FURTHER
EAST. HIGHS WILL REBOUND INTO THE MID AND UPPER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT MAY 17 2014
OVERALL MEAN FLOW WILL CONTINUE TO EVOLVE INTO A BLOCKING PATTERN
WITH A DEEP TROUGH OVER THE SOUTHWEST U.S...RIDGING OVER THE SOUTH
CENTRAL TO SOUTHEAST PART OF THE COUNTRY AND TROUGHING OVER THE
NORTHEAST. THE FROST POTENTIAL WILL CONTINUE SUNDAY NIGHT FOR VALLEY
LOCATIONS AND OTHER TYPICALLY COOL SPOTS...WITH SURFACE HIGH
PRESSURE OVER THE UPPER OH VALLEY...AND MOSTLY CLEAR SKIES AND LIGHT
WINDS. SOME VALLEY LOCATIONS COULD DROP INTO THE UPPER 30S BY MONDAY
MORNING. WE WILL SEE A WARMING TREND EARLY NEXT WEEK AS UPPER LEVEL
RIDGING BEGINS TO BUILD INTO THE SOUTH CENTRAL U.S. AND HEIGHTS RISE
ACROSS THE OHIO VALLEY. MONDAY WILL MARK THE START OF THE WARM UP IN
THE EXTENDED...AS HIGHS ARE EXPECTED TO RISE TO AROUND 70 DEGREES
ACROSS THE AREA. DAYTIME MAXIMUM TEMPERATURES WILL TOP OUT IN THE
UPPER 70S AND LOWER 80S THE REST OF THE WEEK AS THE RIDGE
STRENGTHENS. EASTERN KENTUCKY WILL REMAIN ON THE NORTHEAST PERIPHERY
OF THE UPPER LEVEL RIDGE...AND REMAIN SUSCEPTIBLE TO PERIODS OF
SHOWERS AND STORMS FROM MIDWEEK ON. A SURFACE BOUNDARY MAY ALSO
BECOME NEARLY STATIONARY ACROSS THE AREA BY LATE IN THE WEEK FURTHER
ENHANCING PRECIPITATION CHANCES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 752 AM EDT SAT MAY 17 2014
IFR OR WORSE FOG WILL BURN OFF THROUGH 14Z. AN UPPER LEVEL
DISTURBANCE WILL PASS THROUGH THE TENNESSEE VALLEY DURING THE
DAY...ALLOWING FOR ISOLATED SHOWER DEVELOPMENT ACROSS PORTIONS OF THE
CUMBERLAND VALLEY. IT WILL REMAIN DRY ELSEWHERE...BESIDES A FEW
STAY SPRINKLES OR VERY LIGHT RAIN SHOWERS. CLOUDS WILL LOWER DURING
THE DAY...BUT WILL REMAIN MAINLY VFR. SKIES WILL CLEAR OUT TOWARDS
DUSK. WSW WINDS OF 5 TO 10 KTS WILL ENGAGE DURING DAY...BEFORE
BECOMING LIGHT TOWARDS SUNSET.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GEOGERIAN
LONG TERM...SBH/AR
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS GRAY ME
936 AM EDT SAT MAY 17 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY THROUGH THE FORECAST AREA TODAY.
THIS FRONT WILL THEN BECOME STATIONARY IN EASTERN MAINE. UPPER
LEVEL LOW PRESSURE WILL THEN MOVE OVERHEAD BY MONDAY AND REMAIN
NEAR THE AREA THROUGH THE WEEK RESULTING IN AN UNSETTLED WEATHER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...HAVE UPDATE FORECAST POPS AND TEMPS. PRECIPITATION ENDING
FROM SOUTHWEST TO NORTHEAST AND CLOUDS CLEARING ALSO IN SW NEW HAMPSHIRE.
HAVE ISSUED A FLOOD WARNING FOR THE PEMIGEWASSET RIVER AT
WOODSTOCK.
PREV DISC...
SHOWERS CONTINUE TO FORM AND RACE INTO MAINE OFF THE GULF OF
MAINE DURING THE EARLY MORNING HOURS. LARGER BAND OF CONVECTION
WITH THE ASSOCIATED COLD FRONT WILL MOVE EAST THIS
MORNING...REACHING THE PORTLAND AREA BY AROUND 09Z AND CLEARING
THIS SAME REGION AROUND 14Z PER LATEST HRRR MODEL PROJECTS.
THEREFORE...THE HIGHEST POPS WILL BE IN DURING THE EARL TO MID
MORNING HOURS. NO SIGNIFICANT WIND SHIFT TIL LATER IN THE DAY...SO
CLEARING WILL BE CONFINED TO NEW HAMPSHIRE AND FAR WESTERN MAINE
LATER TODAY.
USED BLEND OF MESO MODEL DATA FOR AFTERNOON HIGH TEMPS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
CLEARING CONTINUES FROM WEST TO EAST TONIGHT INTO SUNDAY...WITH
THE MOST CLOUDINESS HANGING TOUGH IN THE UPSLOPE TERRAIN OF THE
WESTERN MOUNTAINS OF MAINE AND NORTHERN NEW HAMPSHIRE.
OTHERWISE...DESPITE PRESENCE OF UPPER LEVEL TROUGH ON
SUNDAY...FAVORABLE NORTHWEST WINDS WILL ALLOW FOR SOME SUNSHINE
AND MILD TEMPERATURES. THERE WILL BE A SLIGHT CHANCE FOR A SHOWER
WHERE MOISTURE WILL ACCOMPANY LIMITED DYNAMICS OVER EASTERNMOST
PORTIONS OF THE FORECAST AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
AN UPPER CYCLONIC FLOW EARLY IN THE WEEK WILL ALLOW DIURNAL SCT
SHWRS TO DEVELOP EACH AFTN AS HEATING OCCURS. A WEAK RIDGE TRIES TO
BUILD OVER THE REGION BRIEFLY LATE TUE AND WED BUT STILL WITH A
CHC OF SHWRS. ANOTHER UPPER LOW WITH ITS CYCLONIC FLOW AND
INSTBLTY WILL ONCE AGAIN GET CARVED OUT OVER THE NORTHEAST LATER
IN THE WEEK ALLOWING MORE INSTBLTY SHWRS. TEMPS WILL BE NEAR
SEASONAL LEVELS THROUGH THE WEEK.
USED THE SUPERBLEND FOR POPS AND TEMPS.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...AREAS OF IFR AND LIFR CONDITIONS THIS
MORNING...FOLLOWED BY IMPROVING CONDITIONS TO VFR.
LONG TERM...MAINLY VFR CONDS BUT LOWERING TO MVFR IN SCT SHWRS.
&&
.MARINE...
SHORT TERM...SCA TO REMAIN IN PLACE FOR SEAS.
LONG TERM...WINDS/SEAS TO REMAIN BLO SCA CRITERIA.
&&
.FIRE WEATHER...
RAIN AND WETTING CONDITIONS WILL KEEP FUELS MOIST.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ150>154.
&&
$$
TFH
AREA FORECAST DISCUSSION
NWS GRAY ME
651 AM EDT SAT MAY 17 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY THROUGH THE FORECAST AREA TODAY.
THIS FRONT WILL THEN BECOME STATIONARY IN EASTERN MAINE. UPPER
LEVEL LOW PRESSURE WILL THEN MOVE OVERHEAD BY MONDAY AND REMAIN
NEAR THE AREA THROUGH THE WEEK RESULTING IN AN UNSETTLED WEATHER.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...HAVE UPDATED THE GRIDS BASED ON MESOSCALE MODELS AND
TIMING OF THE FRONTAL BAND OF HEAVY PRECIPITATION THIS MORNING.
RIVERS ARE RESPONDING...ESPECIALLY THE SWIFT RIVER IN MAINE AND
PRECIP BROKE OUT AHEAD OF THE MAIN LINE WITH STRONG UPSLOPE
SIGNATURES THE PAST FEW HOURS.
HYDRO...HAVE ISSUED A FLOOD ADVISORY FOR THE UPSLOPE TERRAIN AND A FLOOD
WARNING FOR THE SWIFT RIVER AT ROXBURY.
PREV DISC...
SHOWERS CONTINUE TO FORM AND RACE INTO MAINE OFF THE GULF OF
MAINE DURING THE EARLY MORNING HOURS. LARGER BAND OF CONVECTION
WITH THE ASSOCIATED COLD FRONT WILL MOVE EAST THIS
MORNING...REACHING THE PORTLAND AREA BY AROUND 09Z AND CLEARING
THIS SAME REGION AROUND 14Z PER LATEST HRRR MODEL PROJECTS.
THEREFORE...THE HIGHEST POPS WILL BE IN DURING THE EARL TO MID
MORNING HOURS. NO SIGNIFICANT WIND SHIFT TIL LATER IN THE DAY...SO
CLEARING WILL BE CONFINED TO NEW HAMPSHIRE AND FAR WESTERN MAINE
LATER TODAY.
USED BLEND OF MESO MODEL DATA FOR AFTERNOON HIGH TEMPS.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
CLEARING CONTINUES FROM WEST TO EAST TONIGHT INTO SUNDAY...WITH
THE MOST CLOUDINESS HANGING TOUGH IN THE UPSLOPE TERRAIN OF THE
WESTERN MOUNTAINS OF MAINE AND NORTHERN NEW HAMPSHIRE.
OTHERWISE...DESPITE PRESENCE OF UPPER LEVEL TROUGH ON
SUNDAY...FAVORABLE NORTHWEST WINDS WILL ALLOW FOR SOME SUNSHINE
AND MILD TEMPERATURES. THERE WILL BE A SLIGHT CHANCE FOR A SHOWER
WHERE MOISTURE WILL ACCOMPANY LIMITED DYNAMICS OVER EASTERNMOST
PORTIONS OF THE FORECAST AREA.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AN UPPER CYCLONIC FLOW EARLY IN THE WEEK WILL ALLOW DIURNAL SCT
SHWRS TO DEVELOP EACH AFTN AS HEATING OCCURS. A WEAK RIDGE TRIES TO
BUILD OVER THE REGION BRIEFLY LATE TUE AND WED BUT STILL WITH A
CHC OF SHWRS. ANOTHER UPPER LOW WITH ITS CYCLONIC FLOW AND
INSTBLTY WILL ONCE AGAIN GET CARVED OUT OVER THE NORTHEAST LATER
IN THE WEEK ALLOWING MORE INSTBLTY SHWRS. TEMPS WILL BE NEAR
SEASONAL LEVELS THROUGH THE WEEK.
USED THE SUPERBLEND FOR POPS AND TEMPS.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...AREAS OF IFR AND LIFR CONDITIONS THIS
MORNING...FOLLOWED BY IMPROVING CONDITIONS TO VFR.
LONG TERM...MAINLY VFR CONDS BUT LOWERING TO MVFR IN SCT SHWRS.
&&
.MARINE...
SHORT TERM...SCA TO REMAIN IN PLACE FOR SEAS.
LONG TERM...WINDS/SEAS TO REMAIN BLO SCA CRITERIA.
&&
.FIRE WEATHER...
RAIN AND WETTING CONDITIONS WILL KEEP FUELS MOIST.
&&
.COASTAL SPLASH-OVER...
WILL MONITOR TO SEE IF SWELLS CONTINUE TONIGHT. THE COAST FLOOD
NOMOGRAM IS SHOWING SPLASH-OVER FOR SACO AND POSSIBLY OTHER
COMMUNITIES IN COASTAL YORK AND ROCKINGHAM COUNTIES. ASTRONOMICAL
TIDES WILL BE VERY HIGH AS WELL...WITH 11.1 FEET EXPECTED IN
PORTLAND HARBOR.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ150>154.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1006 AM EDT SAT MAY 17 2014
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL PERSIST OVER THE EASTERN STATES
THROUGH SUNDAY WHILE SURFACE HIGH PRESSURE BUILDS OVER THE REGION.
HIGH PRESSURE REMAINS OVERHEAD THROUGH MONDAY BEFORE MOVING OFF
THE COAST TUESDAY. A COLD FRONT WILL APPROACH THE REGION WEDNESDAY
BEFORE PASSING THROUGH WEDNESDAY NIGHT INTO THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN UPPER LEVEL TROUGH IS LOCATED ACROSS THE GREAT LAKES THIS
MORNING. MULTIPLE DISTURBANCES ARE ROTATING AROUND THE BASE OF THE
TROUGH AND WILL APPROACH THE REGION TODAY AND TONIGHT. HIGH
PRESSURE WILL APPROACH THE REGION FROM THE MIDWEST TODAY.
SUNSHINE WILL CONTINUE THIS MORNING BEFORE CLOUDS INCREASE FROM
THE WEST THIS AFTERNOON. A DISTURBANCE WILL CROSS THE REGION THIS
MORNING FROM THE TN VALLEY WHILE ANOTHER DISTURBANCE CROSSES WV
AND PA THIS AFTERNOON. A CU FIELD WILL DEVELOP ACROSS THE AREA AS
DAYTIME HEATING CONTINUES AND MIXING TO 80-75MB IS EXPECTED. NAM
AND RAP FCST SOUNDINGS HAVE ABOUT 30-50 J/KG BELOW THE CAPPING
INVERSION THIS AFTERNOON. A FEW SHOWERS MAY FORM ACROSS NRN
MD..NOVA AND THE BALTIMORE METRO CLOSER TO THE UPPER LEVEL
DISTURBANCE TO THE NORTH AND WEST. DRY CONDITIONS AT THE SFC WILL
LEAD TO SPRINKLES AND VIRGA TO OCCUR HENCE KEEPING THE FCST DRY
THIS AFTERNOON.
PREVIOUS FORECAST...
HIGH PRESSURE WILL BUILD OVERHEAD TONIGHT...BRINGING DRY AND COOL
CONDITIONS. AN UPPER-LEVEL DISTURBANCE ROTATING AROUND THE TROUGH
MAY BRING SOME MID-LEVEL CLOUDS. MIN TEMPS WILL RANGE FROM THE MID
30S IN SOME OF THE COLDER SPOTS OF THE ALLEGHENY AND POTOMAC
HIGHLANDS TO THE LOWER AND MIDDLE 50S IN DOWNTOWN WASHINGTON AND
BALTIMORE. PATCHY FROST MAY DEVELOP OVER PORTIONS OF THE ALLEGHENY
AND POTOMAC HIGHLANDS. NOT CONFIDENT ENOUGH FOR AN ADVISORY AT
THIS TIME DUE TO A LIGHT GRADIENT WIND AND A POSSIBLE BKN STRATOCU
DECK ALONG AND WEST OF THE ALLEGHENY FRONT.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH SUNDAY
NIGHT WHILE AN UPPER-LEVEL TROUGH REMAINS OVERHEAD. LIMITED
INSTABILITY WILL RESULT IN ANOTHER BKN CU DECK SUNDAY WITH PERHAPS
A FEW SPRINKLES ACROSS THE NORTHERN AND WESTERN PORTIONS OF THE
CWA. HOWEVER...MOST AREAS WILL TURN OUT DRY DUE TO A DOWNSLOPING
NORTHWEST FLOW AND PLENTY OF LOW-LEVEL DRY AIR. MAX TEMPS SUNDAY
WILL REMAIN A FEW DEGREES BELOW CLIMO...RANGING FROM UPPER 50S
AND LOWER 60S IN THE MOUNTAINS TO THE LOWER 70S IN DOWNTOWN
WASHINGTON AND BALTIMORE.
RADIATIONAL COOLING IS EXPECTED SUNDAY NIGHT WITH HIGH PRESSURE
OVERHEAD ALONG WITH LIGHT WINDS...MAINLY CLEAR SKIES AND DRY AIR
IN PLACE. MIN TEMPS WILL RANGE FROM THE LOWER AND MIDDLE 30S IN
SOME OF THE COLDER LOCATIONS OF THE POTOMAC HIGHLANDS AND WESTERN
MARYLAND...TO THE LOWER 50S IN DOWNTOWN WASHINGTON AND BALTIMORE.
A FROST ADVISORY MAY BE NEEDED FOR PORTIONS OF THE POTOMAC
HIGHLANDS AND WESTERN MARYLAND.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THE UPPER-LEVEL TROUGH WILL SHIFT EAST MONDAY WHILE SURFACE HIGH
PRESSURE REMAINS OVERHEAD. MORE DRY CONDITIONS ARE EXPECTED ALONG
WITH SUNSHINE AND LOW RELATIVE HUMIDITY. MAX TEMPS WILL BE FEW
DEGREES WARMER COMPARED TO THE WEEKEND...CLOSER TO CLIMO.
THE SURFACE HIGH WILL MOVE OFF THE COAST TUESDAY AND A RETURN
SOUTHERLY FLOW WILL CAUSE MAX TEMPS TO BE A FEW DEGREES WARMER
ALONG WITH SOME SUNSHINE.
AN UPPER-LEVEL RIDGE WILL BUILD OVER THE SOUTHERN CONUS DURING THE
MIDDLE AND LATTER PORTIONS OF NEXT WEEK WHILE ANOTHER UPPER-LEVEL
LOW DEVELOPS OVER THE GREAT LAKES AND SHIFTS TOWARD NEW ENGLAND. A
NORTHWEST FLOW ALOFT WILL DEVELOP OVER OUR REGION IN BETWEEN THESE
SYSTEMS. THE COLD FRONT ASSOCIATED WITH THE UPPER-LEVEL LOW WILL
APPROACH OUR REGION WEDNESDAY INTO WEDNESDAY NIGHT BEFORE PASSING
THROUGH THURSDAY. THE NORTHWEST FLOW ALOFT ALONG WITH WARM AND
HUMID CONDITIONS AHEAD OF THE COLD FRONT WILL INCREASE THE CHANCE
FOR SHOWERS AND THUNDERSTORMS WEDNESDAY AND THURSDAY. THE FRONT
SHOULD STALL TO OUR SOUTH LATE NEXT WEEK ALLOWING FOR DRIER AND
LESS HUMID CONDITIONS TO RETURN.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. NORTHWEST WINDS WILL
GUST AROUND 15 KNOTS TODAY. A BKN CU DECK IS EXPECTED WITH CIGS
AROUND 5KFT THIS AFTERNOON. WINDS WILL BE LIGHT TONIGHT.
VFR CONDITIONS WILL CONTINUE THROUGH EARLY NEXT WEEK. AN
APPROACHING COLD FRONT MAY TRIGGER SOME SHOWERS AND THUNDERSTORMS
WEDNESDAY.
&&
.MARINE...
A WEAK PRESSURE SURGE IS EXPECTED THIS MORNING BEHIND A COLD
FRONT. A FEW ISOLATED GUSTS UP TO 20KTS ARE POSSIBLE THIS MORNING
ACROSS THE LOWER TIDAL POTOMAC AND MD CHESAPEAKE BAY SOUTH OF
SANDY POINT. THE PRESSURE SURGE IS WEAK AND IS ONLY EXPECTED THIS
MORNING AND THEREFORE SCA IS NOT IN EFFECT. NORTHWEST WINDS WILL
CONTINUE THIS AFTERNOON. ANOTHER WEAK PRESSURE SURGE WILL PASS
THROUGH THE WATERS TONIGHT AND NORTHWEST WINDS WILL BE CLOSE TO
SCA CRITERIA LATE TONIGHT INTO SUNDAY MORNING. GUSTS HAVE BEEN
CAPPED AROUND 15 KNOTS FOR NOW.
HIGH PRESSURE WILL BUILD OVER THE WATERS EARLY NEXT WEEK BEFORE
MOVING OFF THE COAST TUESDAY. A RETURN SOUTHERLY FLOW WILL DEVELOP
DURING THE MIDDLE PORTION OF NEXT WEEK.
&&
.HYDROLOGY...
AREAL FLOOD WARNINGS FOR CREEKS AND STREAMS CONTINUE TO DIMINISH AS
WATER FLOWS INTO THE MAIN STEM RIVERS. THESE WARNINGS WILL LIKELY
BE ALLOWED TO EXPIRE THIS MORNING.
RIVER FLOOD WARNINGS ARE IN EFFECT FOR MANY POINTS ALONG THE
SHENANDOAH...RAPPAHANNOCK... RAPIDAN AND POTOMAC...AND OTHER
TRIBUTARY RIVER BASINS. FLOODING WILL CONTINUE ON THE POTOMAC
UNTIL SUNDAY EVENING. PLEASE SEE LATEST FLOOD WARNINGS FOR FURTHER
DETAILS.
&&
.TIDES/COASTAL FLOODING...
A COASTAL FLOOD WARNING IS IN EFFECT FOR WASHINGTON DC AND
ALEXANDRIA ALONG THE UPPER TIDAL POTOMAC RIVER. FRESHWATER FLOW
WILL CONTINUE TO INCREASE FROM THE POTOMAC RIVER. THIS WILL CAUSE
MODERATE FLOODING AT ALEXANDRIA...AND GEORGETOWN. MODERATE FLOODING
IS EXPECTED AT GEORGETOWN AROUND HIGH TIDE TONIGHT.
MODERATE FLOODING WILL CONTINUE SUNDAY AND PERHAPS SUNDAY NIGHT.
SEE THE COASTAL FLOOD WARNING...WBCCFWLWX FOR FURTHER DETAILS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD WARNING UNTIL 6 AM EDT MONDAY FOR DCZ001.
MD...NONE.
VA...COASTAL FLOOD WARNING UNTIL 6 AM EDT MONDAY FOR VAZ054.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BJL
NEAR TERM...BJL/HAS
SHORT TERM...BJL
LONG TERM...BJL
AVIATION...BJL
MARINE...BJL
HYDROLOGY...HAS
TIDES/COASTAL FLOODING...HAS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1025 AM EDT SAT MAY 17 2014
.SYNOPSIS...
UNSEASONABLY COOL WEATHER WILL LAST THROUGH THE WEEKEND WITH
TEMPERATURES RUNNING ABOUT 10 DEGREES BELOW AVERAGE. A FEW SCATTERED
SHOWERS WILL DEVELOP EACH DAY ESPECIALLY ACROSS THE HIGHER TERRAIN
AWAY FROM THE GREAT LAKES...BUT MOST OF THE TIME WILL BE RAIN FREE.
A SLOW WARMING TREND WILL BEGIN NEXT WEEK WITH THE NEXT CHANCE OF
MORE ORGANIZED RAIN ARRIVING BY THE MIDDLE OF THE WEEK WHEN A WARM
FRONT MOVES INTO THE LOWER GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
FOR TODAY THE AXIS OF THE DEEP MID LEVEL TROUGH WILL SHIFT VERY
SLOWLY EAST ACROSS THE CENTRAL GREAT LAKES...WITH SEVERAL
VORTICITY MAXIMA ON ITS EASTERN FLANK MOVING ACROSS WESTERN NY.
THESE FEATURES WILL PROVIDE SOME LIMITED LARGE SCALE ASCENT AND
MOISTURE. MORE IMPORTANT TO SHOWER POTENTIAL WILL BE DIURNAL
INSTABILITY...WITH LIMITED SURFACE HEATING COMBINING WITH VERY
CHILLY TEMPERATURES ALOFT TO PRODUCE STEEP LOW LEVEL LAPSE RATES.
AHEAD OF THIS WILL BE SOME SUNSHINE LATE THIS MORNING INTO THE
AFTERNOON...HOWEVER THIS WILL FILL IN THIS AFTERNOON WITH
INSTABILITY CUMULUS. SCATTERED RAIN SHOWERS WILL DEVELOP...
MAINLY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND WESTERN
FINGER LAKES. A NARROW BAND OF SHOWERS MAY ALSO DEVELOP THIS
AFTERNOON ALONG A CONVERGENCE ZONE ACROSS THE NIAGARA FRONTIER
DRIVEN BY CHANNELING OF WINDS OVER LAKE ERIE AND ONTARIO. THIS
TYPICALLY SETS UP FROM JUST NORTH OF BUFFALO AND NIAGARA COUNTY
EAST TO NEAR ROCHESTER. WITH RADAR SHOWING A FAIRLY SOLID AREA OF
SHOWERS ACROSS CENTRAL LAKE ERIE AND THE HRRR BRINGING THIS
FEATURE ACROSS THE SOUTHERN TIER DURING THE AFTERNOON HOURS...FEEL
LIKELY POPS ARE JUSTIFIED FOR A PORTION OF THE SOUTHERN TIER. WITH
850M TEMPS AROUND -2C ON THE 12Z BUF SOUNDING...EXPECT HIGHS TO BE
IN THE LOWER 50S ACROSS HIGHER TERRAIN AND ALONG THE IMMEDIATE
LAKESHORE...WITH MID TO UPPER 50S INLAND BUT ACROSS LOWER TERRAIN.
SCATTERED SHOWERS WILL LINGER INTO THE EVENING FROM THE FINGER LAKES
WESTWARD WITH WEAK SYNOPTIC SCALE ASCENT YIELDING SOME SUPPORT TO
THE FADING DIURNAL PROCESSES. THE SHOWERS SHOULD END BY LATE
EVENING...BUT MODEL POINT SOUNDINGS AND RH PLOTS SUGGEST A DECENT
AMOUNT OF CLOUD COVER WILL LINGER OVERNIGHT ACROSS MUCH OF THE
REGION WITH PATCHES OF ENHANCED RH WITHIN THE LONGWAVE TROUGH SLOWLY
MOVING INTO THE AREA. THIS POTENTIAL FOR CLOUD COVER WILL MAKE THE
LOW TEMPERATURE FORECAST TRICKY AND ALSO INFLUENCE THE POTENTIAL FOR
ANY FROST. THE GFS...CANADIAN GEM...AND NAM ALL SHOW A DECENT AMOUNT
OF LOW LEVEL RH REMAINING OVERNIGHT...AND GIVEN THE POSITION OF THE
MID LEVEL TROUGH HAVE OPTED TO INCREASE CLOUD COVER. THIS WILL KEEP
LOW TEMPERATURES IN THE UPPER 30S TO LOWER 40S ON THE LAKE
PLAINS...WITH MID 30S IN THE COOLER INTERIOR SECTIONS. GIVEN THE
EXPECTED CLOUD COVER HAVE LEFT FROST OUT OF THE FORECAST FOR NOW. IF
MORE CLEARING APPEARS LIKELY TONIGHT...FROST WILL BE A DISTINCT
POSSIBILITY AND LATER SHIFTS WILL CONTINUE TO MONITOR TRENDS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
SFC HIGH PRESSURE WILL GENERALLY SUPPORT DRY WX FOR THE BULK OF THE
LOWER GREAT LAKES ON SUNDAY. ALTHOUGH...A FEW NUISANCE SHOWERS CAN`T
BE RULED OUT AS THE UPPER LEVEL TROUGH AXIS SWINGS ACROSS THE REGION
W/IT`S COLD POOL (H85 TEMPS NEAR 0C)WHICH WILL INDUCE DIURNALLY
DRIVEN SHOWERS IN THE FAVORED NW`LY FLOW. THE GREATEST CHANCE FOR
THESE SHOWERS WILL OCCUR OVER THE HIGHER TERRAIN OF THE WESTERN SRN
TIER AND THE FINGER LAKES REGION. OTHERWISE...EXPECT A MIX OF CLOUDS
AND SUNSHINE W/COOL CONDITIONS ELSEWHERE AS HIGH WILL LIKELY MAX OUT
ONLY IN THE UPPER 50S TO LOWER 60S.
LEFTOVER DIURNALLY DRIVEN SHOWERS WILL QUICKLY DISSIPATE ALONG WITH
ITS ASSOCIATED CLOUD COVER SUNDAY EVENING. WITH THE LOSS OF CLOUD
COVER...THERE WILL BE SOME RISK OF PATCHY FROST DEVELOPING ACROSS
THE WESTERN SRN TIER AND PORTIONS OF THE GENESEE VALLEY WHERE IT IS
EXPECTED TO REMAIN MAINLY CLOUD FREE W/LIGHT WINDS OVERNIGHT. ALL
OTHER AREAS WILL LIKELY EXPERIENCE LOWS IN THE LOWER 40S.
THE UPPER LEVEL TROUGH WILL SLOWLY MIGRATE TO THE EAST ALLOWING A WK
SHORT WAVE EMBEDDED WITHIN THE NW`LY FLOW ALOFT TO BRING A SLGT CHANCE
OF SHOWERS ACROSS THE REGION ON MONDAY. FOLLOWING ITS PASSAGE HIGH
PRESSURE ALOFT AND AT THE SFC WILL BUILD INTO THE LOWER GREAT LAKES
MONDAY NIGHT W/DRY WX AND OVERNIGHT LOWS GENERALLY IN THE 40S FOR
MOST LOCATIONS. AGAIN THE LONE EXCEPTION WILL BE ACROSS THE WESTERN
SRN TIER WHERE CLEARING SKIES WILL ALLOW TEMPS TO DIP INTO THE 30S
W/SOME PATCHY FROST.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HIGH PRESSURE ALOFT AND AT THE SFC WILL MAINTAIN PRIMARILY DRY WX
FOR THE MAJORITY OF THE REGION ON TUESDAY. A ROBUST SHORTWAVE OVER
THE CANADIAN PRAIRIES WILL BRING SEVERAL DAYS OF UNSETTLE WX TO THE
LOWER GREAT LAKES STARTING LATE TUESDAY AS IT TRACKS EAST ACROSS
CANADA. THE UPPER LEVEL TROUGH AND SFC LOW WILL REMAIN OVER THE REGION
KEEPING A THREAT OF SHOWERS EACH DAY THROUGH FRIDAY. TEMPERATURES
DURING THIS PERIOD WILL AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL
BEFORE COOLER WX BEGINS TO DEVELOP LATE IN THE WEEK.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
CLOUDS WILL INCREASE FROM SOUTHWEST TO NORTHEAST THIS MORNING AS A
MID LEVEL DISTURBANCE CROSSES THE REGION. EXPECT CIGS TO BE MAINLY
VFR...WITH A FEW PATCHES OF MVFR CIGS LIKELY TO LIFT BETWEEN 15Z
AND 18Z. SCATTERED SHOWERS WILL DEVELOP BY MIDDAY WITH DAYTIME
HEATING...MAINLY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER
AND WESTERN FINGER LAKES. A FEW SHOWERS MAY ALSO DEVELOP ALONG A
LAKE BREEZE BOUNDARY FROM KIAG TO KROC LATER IN THE DAY.
THE SHOWERS WILL DIMINISH DURING THE EVENING WITH THE LOSS OF
DAYTIME HEATING. CLOUDS MAY LINGER MUCH OF THE NIGHT WITH CIGS
MAINLY VFR...ALTHOUGH SOME MVFR IS POSSIBLE ACROSS THE HIGHER
TERRAIN OF THE SOUTHERN TIER AND FINGER LAKES.
OUTLOOK...
SUNDAY AND MONDAY...MAINLY VFR WITH SCATTERED SHOWERS.
TUESDAY...VFR.
WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS
WITH ASSOCIATED BRIEF MVFR.
&&
.MARINE...
MODERATE WESTERLIES WILL DEVELOP TODAY ON THE EAST HALF OF LAKE
ONTARIO WITH CHOPPY WAVE CONDITIONS...BUT SHOULD REMAIN JUST BELOW
SMALL CRAFT ADVISORY CRITERIA. WINDS AND WAVES WILL BE LOWER ON LAKE
ERIE. WEAK HIGH PRESSURE WILL BUILD OVER THE LOWER LAKES TONIGHT AND
SUNDAY WITH A RETURN OF LIGHT WINDS AND FLAT WAVE ACTION. RELATIVELY
LIGHT WINDS WILL THEN LAST THROUGH THE FIRST HALF OF NEXT WEEK AS A
WEAK PRESSURE GRADIENT REMAINS IN PLACE ACROSS THE LOWER LAKES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...AR
LONG TERM...AR
AVIATION...HITCHCOCK/APFFEL
MARINE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
956 AM CDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 936 AM CDT SAT MAY 17 2014
MORNING UPDATE TO ADD A LOW AFTERNOON POP ACROSS THE FAR NORTH.
HIGH RESOLUTION MODELS ARE SUGGESTING SOME POTENTIAL FOR A FEW
SHOWERS LATE. OTHER THAN A SMALL PATCH OF LINGERING LIGHT
FOG/STRATUS NEAR WILLISTON...EARLY MORNING FOG HAS DISSIPATED.
UPDATE ISSUED AT 619 AM CDT SAT MAY 17 2014
CLEAR SKIES AND LIGHT WINDS HAVE ALLOWED FOG TO DEVELOP ACROSS
PARTS OF NORTHWEST NORTH DAKOTA EARLY THIS MORNING. THE LATEST
HRRR CAPTURES THIS WELL...AND SHOWS THE FOG LIFTING QUICKLY THIS
MORNING. WILL ADD PATCHY FOG IN THE NORTHWEST FOR A COUPLE
HOURS...WITH MAINLY CLEAR SKIES ELSEWHERE. THE REMAINDER OF THE
FORECAST IS ON TRACK...AND MADE ONLY MINOR CHANGES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CDT SAT MAY 17 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...NORTHWEST FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
REGION WITH EMBEDDED ENERGY STRETCHING FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS. WEAK HIGH PRESSURE ACROSS THE STATE
RESULTING IN LIGHT AND VARIABLE WINDS EARLY THIS MORNING. SCT-
BKN MID LEVEL CLOUDS NEAR THE MID LEVEL PVA FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS WITH MOSTLY CLEAR CONDITIONS CENTRAL
AND EAST.
WINDS WILL TAKE ON A MORE SOUTHERLY/WESTERLY COMPONENT ACROSS WEST
AND CENTRAL ND AS THE MORNING PROGRESSES WITH HIGH PRESSURE
DRIFTING TO OUR SOUTH. SFC RIDGE WILL REMAIN STRETCHED FROM
EASTERN SD BACK NORTHWEST ACROSS MY AREA THROUGH TODAY.
WHILE SOME MODELS TRY TO GENERATE QPF TODAY...HR MODELS SUCH AS
THE NESTED NAM AND RAP KEEP THINGS DRY. WITH THE SFC RIDGE IN
PLACE...LACK OF GOOD MID LEVEL ENERGY...AND THE UPPER JET PUSHING
OFF TO OUR SOUTH...DO NOT ANTICIPATE ANY PRECIPITATION SO WILL
REMAIN DRY. ALSO...CLOUD DECKS NEAR 8-10K FT AGL SHOULD PREVENT
ANY MEASURABLE PRECIPITATION OVER THE NEXT 24-36 HOURS EVEN IF A
MID LEVEL SHOWER DEVELOPS THIS SAT AFTERNOON/EVENING AS SOME OF
THE MODELS SUGGEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT SAT MAY 17 2014
SUNDAY SHOULD START DRY...BUT RAIN CHANCES WILL INCREASE ACROSS
WESTERN NORTH DAKOTA BY AFTERNOON AS A SURFACE TROUGH STRENGTHENS
ACROSS EASTERN MONTANA / WYOMING. IT APPEARS MUCH OF THE INITIAL
RAIN CHANCES WILL BE IN MONTANA AND WYOMING CLOSER TO THE SURFACE
FEATURE....BUT THE CHANCES SPREAD EAST LATE IN THE AFTERNOON AS
THE FIRST IN A SERIES OF UPPER WAVES MOVES INTO THE REGION.
INSTABILITY INCREASES SUNDAY AFTERNOON / EVENING IN WESTERN NORTH
DAKOTA WITH SBCAPE APPROACHING 1000 J/KG. DEEP LAYER SHEAR
APPROACHES 40-45 KTS...SO THINK AT LEAST A FEW STRONG STORMS ARE
POSSIBLE AND INCLUDED THE MENTION IN THE HAZARDOUS WEATHER
OUTLOOK. THIS ALSO LINES UP WELL WITH THE SPC DAY 2 COMBINED
SEVERE OUTLOOK PROBABILITIES.
THE THUNDERSTORM CHANCES SPREAD ACROSS WESTERN AND CENTRAL NORTH
DAKOTA SUNDAY NIGHT AS A 50 KT LOW LEVEL JET LIFTS INTO THE
REGION. THE MODELS ARE IN GOOD AGREEMENT REGARDING THE RAIN
CHANCES SUNDAY NIGHT...SO WILL KEEP POPS IN THE LIKELY CATEGORY.
MODEL UNCERTAINTY INCREASES ON MONDAY WITH DIFFERING SOLUTIONS
REGARDING THE PROGRESSION OF THE SURFACE LOW. OVERALL...IT APPEARS
THE MODELS ARE FAVORING LESS NEW SHOWER/THUNDERSTORM DEVELOPMENT
MONDAY AFTERNOON...AND CONFINE THE BEST CHANCES TO THE EASTERN
PORTION OF THE FORECAST AREA AS THE LOW MOVES THROUGH.
THE REMAINDER OF THE EXTENDED PERIOD WILL FEATURE PERIODIC WAVES
MOVING THROUGH WEAK RIDGING ACROSS THE NORTHERN PLAINS. THE LATEST
GFS AND ECMWF SHOW A BIT MORE INSTABILITY AVAILABLE THROUGH THE
WEEK...SO HAVE ADDED THUNDERSTORM CHANCES WHERE APPROPRIATE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 936 AM CDT SAT MAY 17 2014
LOW STRATUS/FOG CONTINUES TO LIFT AT KISN THIS MORNING.
OTHERWISE...EXPECT VFR CONDITIONS WITH LIGHT W/SW WINDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...NH
LONG TERM...CK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
620 AM CDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 619 AM CDT SAT MAY 17 2014
CLEAR SKIES AND LIGHT WINDS HAVE ALLOWED FOG TO DEVELOP ACROSS
PARTS OF NORTHWEST NORTH DAKOTA EARLY THIS MORNING. THE LATEST
HRRR CAPTURES THIS WELL...AND SHOWS THE FOG LIFTING QUICKLY THIS
MORNING. WILL ADD PATCHY FOG IN THE NORTHWEST FOR A COUPLE
HOURS...WITH MAINLY CLEAR SKIES ELSEWHERE. THE REMAINDER OF THE
FORECAST IS ON TRACK...AND MADE ONLY MINOR CHANGES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CDT SAT MAY 17 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...NORTHWEST FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
REGION WITH EMBEDDED ENERGY STRETCHING FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS. WEAK HIGH PRESSURE ACROSS THE STATE
RESULTING IN LIGHT AND VARIABLE WINDS EARLY THIS MORNING. SCT-
BKN MID LEVEL CLOUDS NEAR THE MID LEVEL PVA FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS WITH MOSTLY CLEAR CONDITIONS CENTRAL
AND EAST.
WINDS WILL TAKE ON A MORE SOUTHERLY/WESTERLY COMPONENT ACROSS WEST
AND CENTRAL ND AS THE MORNING PROGRESSES WITH HIGH PRESSURE
DRIFTING TO OUR SOUTH. SFC RIDGE WILL REMAIN STRETCHED FROM
EASTERN SD BACK NORTHWEST ACROSS MY AREA THROUGH TODAY.
WHILE SOME MODELS TRY TO GENERATE QPF TODAY...HR MODELS SUCH AS
THE NESTED NAM AND RAP KEEP THINGS DRY. WITH THE SFC RIDGE IN
PLACE...LACK OF GOOD MID LEVEL ENERGY...AND THE UPPER JET PUSHING
OFF TO OUR SOUTH...DO NOT ANTICIPATE ANY PRECIPITATION SO WILL
REMAIN DRY. ALSO...CLOUD DECKS NEAR 8-10K FT AGL SHOULD PREVENT
ANY MEASURABLE PRECIPITATION OVER THE NEXT 24-36 HOURS EVEN IF A
MID LEVEL SHOWER DEVELOPS THIS SAT AFTERNOON/EVENING AS SOME OF
THE MODELS SUGGEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT SAT MAY 17 2014
SUNDAY SHOULD START DRY...BUT RAIN CHANCES WILL INCREASE ACROSS
WESTERN NORTH DAKOTA BY AFTERNOON AS A SURFACE TROUGH STRENGTHENS
ACROSS EASTERN MONTANA / WYOMING. IT APPEARS MUCH OF THE INITIAL
RAIN CHANCES WILL BE IN MONTANA AND WYOMING CLOSER TO THE SURFACE
FEATURE....BUT THE CHANCES SPREAD EAST LATE IN THE AFTERNOON AS
THE FIRST IN A SERIES OF UPPER WAVES MOVES INTO THE REGION.
INSTABILITY INCREASES SUNDAY AFTERNOON / EVENING IN WESTERN NORTH
DAKOTA WITH SBCAPE APPROACHING 1000 J/KG. DEEP LAYER SHEAR
APPROACHES 40-45 KTS...SO THINK AT LEAST A FEW STRONG STORMS ARE
POSSIBLE AND INCLUDED THE MENTION IN THE HAZARDOUS WEATHER
OUTLOOK. THIS ALSO LINES UP WELL WITH THE SPC DAY 2 COMBINED
SEVERE OUTLOOK PROBABILITIES.
THE THUNDERSTORM CHANCES SPREAD ACROSS WESTERN AND CENTRAL NORTH
DAKOTA SUNDAY NIGHT AS A 50 KT LOW LEVEL JET LIFTS INTO THE
REGION. THE MODELS ARE IN GOOD AGREEMENT REGARDING THE RAIN
CHANCES SUNDAY NIGHT...SO WILL KEEP POPS IN THE LIKELY CATEGORY.
MODEL UNCERTAINTY INCREASES ON MONDAY WITH DIFFERING SOLUTIONS
REGARDING THE PROGRESSION OF THE SURFACE LOW. OVERALL...IT APPEARS
THE MODELS ARE FAVORING LESS NEW SHOWER/THUNDERSTORM DEVELOPMENT
MONDAY AFTERNOON...AND CONFINE THE BEST CHANCES TO THE EASTERN
PORTION OF THE FORECAST AREA AS THE LOW MOVES THROUGH.
THE REMAINDER OF THE EXTENDED PERIOD WILL FEATURE PERIODIC WAVES
MOVING THROUGH WEAK RIDGING ACROSS THE NORTHERN PLAINS. THE LATEST
GFS AND ECMWF SHOW A BIT MORE INSTABILITY AVAILABLE THROUGH THE
WEEK...SO HAVE ADDED THUNDERSTORM CHANCES WHERE APPROPRIATE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 619 AM CDT SAT MAY 17 2014
PATCHY FOG ACROSS PARTS OF NORTHWEST NORTH DAKOTA EARLY THIS
MORNING MAY BRIEFLY AFFECT VISIBILITIES AT KISN. OTHERWISE...VFR
CONDITIONS ARE EXPECTED AT ALL AERODROMES FOR THE 12Z TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...NH
LONG TERM...CK
AVIATION...NH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
645 AM CDT SAT MAY 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CDT SAT MAY 17 2014
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING UPPER LEVEL TROUGH OVER
THE UPPER GREAT LAKES REGION WITH SEVERAL VORTICES WRAPPING AROUND
THE UPPER LEVEL TROUGH. LATEST FOG SATELLITE SHOWING SKIES BEGIN
TO CLEAR ACROSS THE FORECAST AREA.
MAIN FORECAST CONCERNS TODAY ARE SMALL PRECIPITATION CHANCES ACROSS
EASTERN PARTS OF FORECAST AREA. 17.00Z GFS/NAM CONTINUE TO SHOW
STEEPENING LOW LEVEL LAPSE RATES AND WEAK INSTABILITY IN THE 800MB-
650MB LAYER PER BUFKIT SOUNDINGS OVER CENTRAL WISCONSIN BY 18Z
SATURDAY. WILL CONTINUE WITH SMALL CHANCES OF SHOWERS OVER THE FAR
EASTERN AREAS OF THE FORECAST AREA.
TONIGHT...UPPER LEVEL TROUGH PULLS AWAY FROM THE AREA AND RIDGING
ALOFT BUILDS INTO THE FORECAST AREA. SKIES WILL BE MAINLY ACROSS THE
REGION...HOWEVER...WITH WARMER AIR ADVECTING INTO THE UPPER
MIDWEST...925MB TEMPS WARMING TO AROUND PLUS 10 DEGREES CELSIUS
ACROSS FORECAST AREA...AND SLIGHTLY TIGHTER PRESSURE GRADIENT ACROSS
FORECAST AREA. MINIMUM TEMPERATURES WILL BE A FEW DEGREES WARMER
THAN THIS MORNING LOWS. DO NOT ANTICIPATE ANY WIDESPREAD FROST
AND ANY FROST WOULD BE CONTAINED TO THE FAR NORTHERN FORECAST
AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 310 AM CDT SAT MAY 17 2014
UPPER LEVEL RIDGE ENTRENCHED OVER FORECAST AREA SUNDAY AND REGION
UNDER WARM AIR ADVECTION WILL PRODUCE HIGH TEMPERATURES IN THE 60S
TO AROUND 70.
FOCUS TURNS TO PRECIPITATION CHANCES MONDAY INTO MONDAY NIGHT.
SHORTWAVE TROUGH FLATTENS UPPER LEVEL TROUGH AND TRACKS ACROSS
NORTHERN HALF OF FORECAST AREA. THE 17.00Z GFS/NAM/ECMWF ARE
TRENDING FASTER AND MORE PROGRESSIVE WITH SHORTWAVE TROUGH. THE
MODELS INDICATE DECENT MOISTURE TRANSPORT AND CONVERGENCE AND FOCUS
THIS OVER THE NORTHERN HALF OF THE FORECAST AREA BY 18Z MONDAY. THE
17.00Z GFS/NAM SHOW DECENT 0-3KM SHEAR AROUND 30 KNOTS IN
ASSOCIATION WITH SHORTWAVE TROUGH. THE 17.00Z NAM INDICATES 200-400
J/KG 0-6KM MOST UNSTABLE CAPE WITH ALL THE MODELS SHOWING NO SURFACE
BASE CAPE. THUNDERSTORM DEVELOPMENT SHOULD REMAIN ELEVATED OVER
FORECAST AREA MONDAY INTO MONDAY NIGHT. AT THIS TIME...NOT EXPECTING
ANY WIDESPREAD SEVERE...HOWEVER CANNOT RULE OUT ISOLATED SEVERE
POTENTIAL...GIVEN THE STRONG SHEAR. CONFIDENCE TOO LOW FOR SEVERE
POTENTIAL TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK.
TUESDAY THROUGH FRIDAY...THE COMBINATION OF SHORTWAVE TROUGH AND
ASSOCIATED LOW PRESSURE/SURFACE FRONT MOVING EAST AND SOUTH OF
FORECAST AREA AND SURFACE RIDGE BUILDING INTO NORTHERN HALF OF
MINNESOTA AND WISCONSIN WILL SHIFT FOCUS OF SHOWERS AND THUNDERSTORM
DEVELOPMENT TO THE SOUTH OF FORECAST AREA. THIS SHOULD ALLOW
FORECAST TO BE MAINLY DRY THROUGH PERIOD. TEMPERATURES TUESDAY
THROUGH FRIDAY SHOULD BE NEAR NORMAL WITH HIGHS CLIMBING INTO THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 645 AM CDT SAT MAY 17 2014
A SHORT WAVE TROUGH OVER WESTERN ONTARIO WILL MOVE SOUTH ACROSS
WESTERN WISCONSIN TODAY. THIS SYSTEM WILL BRING WITH IT A BROKEN 8
TO 10K DECK OF CLOUDS INTO THE AREA FOR TODAY. SOUTHWEST WINDS IN
THE 6 TO 10 KNOT RANGE WILL SHIFT TO WEST BY 17.15Z.
FOR TONIGHT...THE MODELS ARE DIFFERING ON WHEN THE LOW CLOUDS MAY
EXIT THE THE AREA. BOTH THE NAM AND RAP KEEP THE 8 TO 10K BROKEN
DECK OF CLOUDS IN THE AREA. MEANWHILE...THE GFS SCATTERS THEM
OUT. WITH THEIR APPEARING TO BE SUBSIDENCE IN THE WAKE OF THIS
WAVE...DECIDED TO FOLLOW THE GFS.
&&
.HYDROLOGY...
ISSUED AT 310 AM CDT SAT MAY 17 2014
WATER LEVELS ALONG THE MISSISSIPPI RIVER WILL CONTINUE TO RUN HIGH
THROUGH THE WEEKEND AND INTO NEXT WEEK. SOME MINOR FLOODING IS
ALREADY OCCURRING OR EXPECTED TO OCCUR INTO NEXT WEEK.
FOR MORE DETAILED INFORMATION...LOOK ON OUR INTERNET PAGE AT
WWW.WEATHER.GOV/LACROSSE. CLICK ON THE NEWS STORY AT THE TOP OF
THE PAGE PERTAINING TO THE MISSISSIPPI RIVER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY UNTIL 7 AM CDT THIS MORNING FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...FROST ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MNZ079-086>088-
094>096.
IA...FROST ADVISORY UNTIL 7 AM CDT THIS MORNING FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...BOYNE
HYDROLOGY...DTJ
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
252 PM CDT SAT MAY 17 2014
.DISCUSSION...
331 AM CDT
AFTER THE INCREDIBLY LATE TASTE OF WINTER FOR PARTS OF THE AREA ON
FRIDAY...A FAIRLY QUIET WEATHER PATTERN IS SHAPING UP ALONG WITH A
NICE WARMING TREND INTO NEXT WEEK. THERE ARE NO SIGNIFICANT FORECAST
CONCERNS AFTER A WEEK AND A HALF OR SO OF ACTIVE WEATHER...THOUGH
THERE ARE SOME PERIODIC CHANCES FOR TSRA IN THE EXTENDED FORECAST
PERIOD. ADDITIONAL MINOR CONCERN IS WHICH DAYS ARE MOST FAVORED FOR
LAKE COOLING.
SHORT TERM...TODAY THROUGH MONDAY NIGHT
W/V IMAGERY THIS MORNING SHOWS ANOMALOUSLY DEEP UPPER TROUGH OVER
EASTERN NOAM. AGAIN SOME INCREDIBLY COLD 500 MB AND 850 MB TEMPS ON
THE 00Z RAOBS FOR THIS TIME OF YEAR...WITH -29C AT H5 AT KGRB AND
KILN AND -2C AT DVN AT H85. AT THE SURFACE...WEAK PRESSURE GRADIENT
ACROSS THE REGION AND SURFACE HIGH CENTERED OVER THE CENTRAL PLAINS.
TODAY AND TONIGHT...IT WILL BE A CHILLY START TO THE DAY WITH PARTLY
CLOUDY SKIES AND PATCHY TO AREAS OF FROST AND PATCHY GROUND FOG. THE
VERY COLD MIDLEVEL TEMPERATURES OVER THE AREA WILL SUPPORT A RAPID
BLOSSOMING OF FAIRLY HIGH-BASED STRATOCUMULUS BY MID TO LATE MORNING
OVER MUCH OF THE AREA AS LAPSE RATES STEEPEN. SOUNDINGS SHOW SOME
AVAILABLE CAPE DUE TO STEEP MIDLEVEL LAPSE RATES BUT LARGE T/TD
SPREADS AND OVERALL FORCING BEING FOCUSED MAINLY EAST OF THE AREA
THROW SOME DOUBT IN MUCH MORE THAN ISOLATED SHRA COVERAGE FROM BKN
STRATOCU DECK. THUS LOWERED POPS SOME INTO THE SLIGHT CHANCE RANGE.
WEAK WAA ALOFT DURING AFTN SUPPORTS HIGHS MOST AREAS REACHING NEAR
OR AROUND 60 DEGREES BASED ON 850/925 MB CLIMO. A WEAK LAKE BREEZE
MAY MAKE IT ONSHORE INTO CHICAGO AND PARTS OF NW IN SHORE DURING
AFTN AND KEEP THINGS SLIGHTLY COOLER THERE. DIURNALLY DRIVEN
STRATOCU SHOULD SCATTER OUT BY EARLY THIS EVENING...SETTING THE
STAGE FOR ANOTHER CHILLY NIGHT WITH LOWS IN UPPER 30S AND LOW 40S
OUTSIDE OF CHICAGO. SURFACE HIGH WILL BE SETTLING OVER EASTERN OH
VALLEY BY SUNDAY MORNING BUT WEAK GRADIENT WILL PREVENT SOUTHERLY
WINDS FROM INCREASING AND KEEPING TEMPS WARMER.
SUNDAY...SHAPING UP TO BE A GREAT DAY FOR OUTDOOR ACTIVITIES. OTHER
THAN SOME CIRRUS AND FAIR WEATHER CU...EXPECT PLENTY OF SUNSHINE AND
HIGHS JUST BELOW NORMAL INTO THE UPPER 60S. BUMPED UP TEMPERATURES
SLIGHTLY FROM PREVIOUS FORECAST ACCOUNTING FOR DRY AIR MASS BEING
CONDUCIVE TO MAXIMIZE HEATING BY SUN AS WELL AS CLOSER TO 925 MB
CLIMO. A WEAK LAKE BREEZE COULD PUSH ONTO PORTION OF SHORE BY LATE
AFTERNOON BUT LIKELY TOO LATE TO IMPACT HIGH TEMPERATURES.
MONDAY AND MONDAY NIGHT...WARM ADVECTION WILL CONTINUE TO INCREASE
DUE TO MIDLEVEL HEIGHT RISES. A FAIRLY DEEP UPPER TROUGH NEAR THE
WEST COAST WILL FORCE DOWNSTREAM RIDGING ACROSS THE MIDWEST. MID AND
HIGH CLOUDS ARE EXPECTED TO INCREASE FROM THE WEST DURING THE
AFTERNOON IN THE WARM ADVECTION PATTERN...BUT ACTUAL SHOWER ACTIVITY
LIKELY TO REMAIN WEST OF THE CWA. TEMPERATURES WILL WARM A FEW MORE
DEGREES TO AROUND 70/LOW 70S. THE EXCEPTION WILL BE THE IL LAKEFRONT
BASICALLY FROM DOWNTOWN CHICAGO AND NORTH WHICH WILL BE KEPT COOLER
IN THE LOWER 60S BY PERSISTENT SOUTHEAST COMPONENT TO THE WINDS.
GUIDANCE IS CONSISTENT ON A STRONG LOW LEVEL JET DEVELOPING MONDAY
NIGHT IN ADVANCE OF SURFACE LOW PRESSURE ACROSS THE PLAINS. NOSE OF
THE JET AND BEST CONVERGENCE SHOULD BE MAINLY NORTH OF CWA...BUT
CANNOT RULE OUT SOME SHRA DEVELOPMENT FOR NORTHERN 2/3 OF CWA. STEEP
LAPSE RATES FROM EML BEING ADVECTED OVER REGION...SO MENTIONED
SLIGHT CHANCE FOR TSRA.
LONG TERM...TUESDAY THROUGH FRIDAY...
850/925 MB TEMPS ARE PROGGED TO SOAR INTO THE MID TO HIGH TEENS
ON TUESDAY...SO MANY AREAS HAVE A GOOD SHOT TO REACH OR EXCEED 80
BY A FEW DEGREES EVEN WITH POTENTIAL FOR ONLY PARTIAL SUNSHINE.
FAR NORTHEAST IL COULD STILL BE KEPT COOLER BY SLIGHT SOUTHEAST
COMPONENT TO WIND THERE. FORECAST SOUNDINGS SHOW THAT ATMOSPHERE
COULD REMAIN LARGELY CAPPED TO CONVECTION UNLESS A MIDLEVEL WAVE
IS STRONG ENOUGH TO BREAK CAP. HOWEVER FOR NOW MAINTAINED GUIDANCE
BLEND SLIGHT TO LOW CHANCE POPS.
BETTER CHANCE FOR CONVECTION OVER NORTHERN HALF OF CWA WILL COME
WITH APPROACH OF SURFACE COLD FRONT TUESDAY EVENING NIGHT. GUIDANCE
IN DECENT AGREEMENT IN FRONTAL BOUNDARY ONLY SLOWLY PROGRESSING
SOUTH WEDNESDAY AND THURSDAY AND ELEVATED FRONT LAGGING EVEN MORE.
THUS THERE COULD BE SOME CONVECTIVE ACTIVITY INTO SOUTHERN HALF TO
THIRD OF CWA DURING THAT PERIOD...WITH BETTER CHANCE IN FAR SOUTH
CLOSER TO FRONTAL BOUNDARY. WEDNESDAY WILL BE ANOTHER WARM DAY FOR
MOST OF THE AREA WITH HIGHS IN UPPER 70S TO LOW 80S INLAND. THIS IS
DESPITE THE COLD FRONT LIKELY TO HAVE PUSHED INTO SOUTHERN CWA.
THE EXCEPTION TO THE WARMTH WILL BE THE LAKEFRONT AS A LAKE BREEZE
WILL DEVELOP EARLY AND KEEP TEMPERATURES 10 OR MORE DEGREES
COOLER. THURSDAY WILL BE SIMILAR BUT LIKELY NOT QUITE AS WARM
INLAND. NEXT FRIDAY IT APPEARS THAT SURFACE HIGH WILL BE OVER
WESTERN LAKES...WHICH SHOULD FAVOR DRY FORECAST. TEMPERATURES
SHOULD BE NEAR TO SLIGHTLY BELOW SEASONABLE INLAND BUT AGAIN
SEVERAL DEGREES COOLER NEAR THE LAKE.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* A FEW SPRINKLES THIS AFTERNOON.
RATZER
//DISCUSSION...UPDATED 18Z...
WEAK MID-LEVEL DISTURBANCE PASSING OVER THE AREA EARLY THIS
AFTERNOON WITH COLD TEMPS ALOFT LEADING TO VFR BROKEN
STRATOCUMULUS DECK. BEST CHANCES FOR SOME SCATTERED SHOWERS
APPEARS TO BE OFF TO THE EAST/SOUTHEAST OF THE CHICAGO TERMINALS
AHEAD OF THIS DISTURBANCE...WHERE VISIBILE SATELLITE IMAGERY
DEPICTS DEEPER CU FIELD. WHILE A FEW WEAK RADAR RETURNS ACROSS
SOUTHERN WI AND NORTHERN IL SUGGEST A SPRINKLE OR TWO POSSIBLE...
PRECIP IS NOT EXPECTED TO HAVE A SIGNIFICANT IMPACT ON THE
TERMINALS.
OTHERWISE...WESTERLY WINDS BETWEEN 250-290 DEGREES EXPECTED THIS
AFTERNOON WITH SPEEDS AROUND 10 KT AND OCCASIONAL GUSTS 13-16 KT
OR SO. SURFACE HIGH PRESSURE OVER OHIO VALLEY DRIFTS EAST SUNDAY
ALLOWING MORE OF A SOUTHWEST WIND. BOTH TODAY AND SUNDAY THERE
SHOULD BE ENOUGH WESTERLY COMPONENT TO KEEP LAKE BREEZE EAST OF
ORD/MDW.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE ALL ELEMENTS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA DURING THE NIGHT.
TUESDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA.
WEDNESDAY...EAST FLOW.
THURSDAY...EAST FLOW. SLIGHT CHANCE OF TSRA DURING THE NIGHT.
FRIDAY...EAST FLOW.
MTF
&&
.MARINE...
212 AM CDT
WEAK LOW PRESSURE WILL MOVE EASTWARD JUST NORTH OF THE GREAT
LAKES TODAY WHICH WILL ACT TO TIGHTEN THE PRESSURE
GRADIENT...NAMELY OVER THE NORTHERN TWO-THIRDS OR SO. DID END UP
INCREASING SPEEDS/GUSTS A FEW KNOTS BASED ON THIS. THE LOW
BASICALLY WASHES OUT THOUGH THE PRESSURE GRADIENT ACROSS THE LAKE
LOOKS TO HOLD ITS OWN THROUGH THE WEEKEND...AS HIGH PRESSURE
BECOMES STATIONARY OVER THE OHIO RIVER VALLEY AND LOW PRESSURE
DEVELOPS ACROSS THE HIGH PLAINS. THIS WILL SPELL CONTINUED
SOUTHERLY FLOW FOR THE LAKE ON MONDAY AND TUESDAY. THE LOW
PRESSURE ORIGINATING IN THE PLAINS LOOKS TO MOVE ACROSS THE
NORTHERN LAKES ON LATE TUESDAY OR EARLY WEDNESDAY...WHICH WOULD
FAVOR A COOL FRONT PASSAGE NEAR THAT TIME...TURNING WINDS WESTERLY
AND THEN NORTHWEST OR NORTH DURING THE LATTER HALF OF THE WEEK.
THIS WOULD LOOK TO RESULT IN AT LEAST CLOSE TO SMALL CRAFT
ADVISORY WAVE CONDITIONS FOR THE INDIANA AND POSSIBLY ILLINOIS
NEARSHORE AREAS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
228 PM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 220 PM CDT Sat May 17 2014
SHORT TERM...Tonight through Tuesday
Warming trend slated for the first part of the new work week with
shower and thunderstorm chances increasing on Wednesday and Thu as
a frontal boundary settles south into our area.
Large cold upper low that has been with us for several days is
finally moving away from our area over the next 24 to 36 hours
bringing a rather quiet weather scene to the region through Tuesday.
Models are in good agreement with respect to the placement of the
surface ridge over the Midwest into early next week bringing
pleasantly mild days and comfortably cool nights. Speaking of cool
nights, it looks like another one tonight as winds become nearly
calm under a mostly clear sky, leading to chilly early morning
lows, although not as cool as early this morning. Will go at or a
few degrees below guidance tonight. The high will shift well to
our east by late Sunday into Monday allowing a return southerly
flow to develop across our west Monday.
A shortwave trof and attendant cold front will track east and
southeast across the upper Midwest on Tuesday with strong low level
warm advection in advance of the system which will help push afternoon
temperatures above normal for a change. Main question will be coverage
of warm advection/nocturnal convection Monday night into Tuesday
morning ahead of the upper wave. Forecast models suggest the higher
POPs will remain just to our north where the more favorable low-mid
level flow and instability will be co-located with low chance POPs
slipping south into our far northern areas Tuesday night as the
frontal boundary edges south into north-central Illinois.
LONG TERM...Wednesday through Saturday
As the upper trof amplifies somewhat over the eastern Great Lakes late
Wednesday into Wednesday night, our POPs will start to increase from
north to south. Models indicating the surface front will shift south
of the Ohio Valley by Friday morning as surface high pressure over
southern Canada builds south into the Great Lakes. At the same time,
an upper low over the southwest U.S. is expected to track slowly
east with several shortwaves embedded in the southwest flow ahead
of the upper wave. These low amplitude waves will interact with the
stalled frontal boundary to our south late Friday into the holiday
weekend setting up what to looks to be an unsettled weather pattern
over the Midwest. Above normal temperatures to start the period off
with will transition into normal or slightly below normal levels
towards the weekend with chances for showers and thunderstorms,
especially late Friday night through Saturday.
Smith
&&
.AVIATION...
ISSUED 1250 PM CDT Sat May 17 2014
Extensive cu field out there this morning and although the upper
low should move more to the east, cu rule still placing some cu
over Central Illinois tomorrow. High pressure ridge is weak and
keeping the cu scattered. Model soundings have moisture at about
5kft. Cu and Altocu in the short term should clear up after
sunset as winds become variable and light. Tomorrow morning the
winds will pick up an increasingly southerly component. VFR
throughout.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
228 PM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 220 PM CDT Sat May 17 2014
SHORT TERM...Tonight through Tuesday
Warming trend slated for the first part of the new work week with
shower and thunderstorm chances increasing on Wednesday and Thu as
a frontal boundary settles south into our area.
Large cold upper low that has been with us for several days is
finally moving away from our area over the next 24 to 36 hours
bringing a rather quiet weather scene to the region through Tuesday.
Models are in good agreement with respect to the placement of the
surface ridge over the Midwest into early next week bringing
pleasantly mild days and comfortably cool nights. Speaking of cool
nights, it looks like another one tonight as winds become nearly
calm under a mostly clear sky, leading to chilly early morning
lows, although not as cool as early this morning. Will go at or a
few degrees below guidance tonight. The high will shift well to
our east by late Sunday into Monday allowing a return southerly
flow to develop across our west Monday.
A shortwave trof and attendant cold front will track east and
southeast across the upper Midwest on Tuesday with strong low level
warm advection in advance of the system which will help push afternoon
temperatures above normal for a change. Main question will be coverage
of warm advection/nocturnal convection Monday night into Tuesday
morning ahead of the upper wave. Forecast models suggest the higher
POPs will remain just to our north where the more favorable low-mid
level flow and instability will be co-located with low chance POPs
slipping south into our far northern areas Tuesday night as the
frontal boundary edges south into north-central Illinois.
LONG TERM...Wednesday through Saturday
As the upper trof amplifies somewhat over the eastern Great Lakes late
Wednesday into Wednesday night, our POPs will start to increase from
north to south. Models indicating the surface front will shift south
of the Ohio Valley by Friday morning as surface high pressure over
southern Canada builds south into the Great Lakes. At the same time,
an upper low over the southwest U.S. is expected to track slowly
east with several shortwaves embedded in the southwest flow ahead
of the upper wave. These low amplitude waves will interact with the
stalled frontal boundary to our south late Friday into the holiday
weekend setting up what to looks to be an unsettled weather pattern
over the Midwest. Above normal temperatures to start the period off
with will transition into normal or slightly below normal levels
towards the weekend with chances for showers and thunderstorms,
especially late Friday night through Saturday.
Smith
&&
.AVIATION...
ISSUED 1250 PM CDT Sat May 17 2014
Extensive cu field out there this morning and although the upper
low should move more to the east, cu rule still placing some cu
over Central Illinois tomorrow. High pressure ridge is weak and
keeping the cu scattered. Model soundings have moisture at about
5kft. Cu and Altocu in the short term should clear up after
sunset as winds become variable and light. Tomorrow morning the
winds will pick up an increasingly southerly component. VFR
throughout.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
228 PM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 220 PM CDT Sat May 17 2014
SHORT TERM...Tonight through Tuesday
Warming trend slated for the first part of the new work week with
shower and thunderstorm chances increasing on Wednesday and Thu as
a frontal boundary settles south into our area.
Large cold upper low that has been with us for several days is
finally moving away from our area over the next 24 to 36 hours
bringing a rather quiet weather scene to the region through Tuesday.
Models are in good agreement with respect to the placement of the
surface ridge over the Midwest into early next week bringing
pleasantly mild days and comfortably cool nights. Speaking of cool
nights, it looks like another one tonight as winds become nearly
calm under a mostly clear sky, leading to chilly early morning
lows, although not as cool as early this morning. Will go at or a
few degrees below guidance tonight. The high will shift well to
our east by late Sunday into Monday allowing a return southerly
flow to develop across our west Monday.
A shortwave trof and attendant cold front will track east and
southeast across the upper Midwest on Tuesday with strong low level
warm advection in advance of the system which will help push afternoon
temperatures above normal for a change. Main question will be coverage
of warm advection/nocturnal convection Monday night into Tuesday
morning ahead of the upper wave. Forecast models suggest the higher
POPs will remain just to our north where the more favorable low-mid
level flow and instability will be co-located with low chance POPs
slipping south into our far northern areas Tuesday night as the
frontal boundary edges south into north-central Illinois.
LONG TERM...Wednesday through Saturday
As the upper trof amplifies somewhat over the eastern Great Lakes late
Wednesday into Wednesday night, our POPs will start to increase from
north to south. Models indicating the surface front will shift south
of the Ohio Valley by Friday morning as surface high pressure over
southern Canada builds south into the Great Lakes. At the same time,
an upper low over the southwest U.S. is expected to track slowly
east with several shortwaves embedded in the southwest flow ahead
of the upper wave. These low amplitude waves will interact with the
stalled frontal boundary to our south late Friday into the holiday
weekend setting up what to looks to be an unsettled weather pattern
over the Midwest. Above normal temperatures to start the period off
with will transition into normal or slightly below normal levels
towards the weekend with chances for showers and thunderstorms,
especially late Friday night through Saturday.
Smith
&&
.AVIATION...
ISSUED 1250 PM CDT Sat May 17 2014
Extensive cu field out there this morning and although the upper
low should move more to the east, cu rule still placing some cu
over Central Illinois tomorrow. High pressure ridge is weak and
keeping the cu scattered. Model soundings have moisture at about
5kft. Cu and Altocu in the short term should clear up after
sunset as winds become variable and light. Tomorrow morning the
winds will pick up an increasingly southerly component. VFR
throughout.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
228 PM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 220 PM CDT Sat May 17 2014
SHORT TERM...Tonight through Tuesday
Warming trend slated for the first part of the new work week with
shower and thunderstorm chances increasing on Wednesday and Thu as
a frontal boundary settles south into our area.
Large cold upper low that has been with us for several days is
finally moving away from our area over the next 24 to 36 hours
bringing a rather quiet weather scene to the region through Tuesday.
Models are in good agreement with respect to the placement of the
surface ridge over the Midwest into early next week bringing
pleasantly mild days and comfortably cool nights. Speaking of cool
nights, it looks like another one tonight as winds become nearly
calm under a mostly clear sky, leading to chilly early morning
lows, although not as cool as early this morning. Will go at or a
few degrees below guidance tonight. The high will shift well to
our east by late Sunday into Monday allowing a return southerly
flow to develop across our west Monday.
A shortwave trof and attendant cold front will track east and
southeast across the upper Midwest on Tuesday with strong low level
warm advection in advance of the system which will help push afternoon
temperatures above normal for a change. Main question will be coverage
of warm advection/nocturnal convection Monday night into Tuesday
morning ahead of the upper wave. Forecast models suggest the higher
POPs will remain just to our north where the more favorable low-mid
level flow and instability will be co-located with low chance POPs
slipping south into our far northern areas Tuesday night as the
frontal boundary edges south into north-central Illinois.
LONG TERM...Wednesday through Saturday
As the upper trof amplifies somewhat over the eastern Great Lakes late
Wednesday into Wednesday night, our POPs will start to increase from
north to south. Models indicating the surface front will shift south
of the Ohio Valley by Friday morning as surface high pressure over
southern Canada builds south into the Great Lakes. At the same time,
an upper low over the southwest U.S. is expected to track slowly
east with several shortwaves embedded in the southwest flow ahead
of the upper wave. These low amplitude waves will interact with the
stalled frontal boundary to our south late Friday into the holiday
weekend setting up what to looks to be an unsettled weather pattern
over the Midwest. Above normal temperatures to start the period off
with will transition into normal or slightly below normal levels
towards the weekend with chances for showers and thunderstorms,
especially late Friday night through Saturday.
Smith
&&
.AVIATION...
ISSUED 1250 PM CDT Sat May 17 2014
Extensive cu field out there this morning and although the upper
low should move more to the east, cu rule still placing some cu
over Central Illinois tomorrow. High pressure ridge is weak and
keeping the cu scattered. Model soundings have moisture at about
5kft. Cu and Altocu in the short term should clear up after
sunset as winds become variable and light. Tomorrow morning the
winds will pick up an increasingly southerly component. VFR
throughout.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
1254 PM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sat May 17 2014
A little bit of a cyclonic turn to the winds still as the upper
trof slowly moves out of the Midwest. But between that and plenty
of moisture at llvls, cu field filling in on sat imagery this
morning. Some of those cu starting to get a bit heavy and showing
up on radar. There is a moderate amount of dry air to help cut
down overall precip accumulations, but activity is likely to be
very isolated anyway. Have expanded the iso mention, but no large
scale updates are anticipated at this time.
&&
.AVIATION...
ISSUED 1250 PM CDT Sat May 17 2014
Extensive cu field out there this morning and although the upper
low should move more to the east, cu rule still placing some cu
over Central Illinois tomorrow. High pressure ridge is weak and
keeping the cu scattered. Model soundings have moisture at about
5kft. Cu and Altocu in the short term should clear up after
sunset as winds become variable and light. Tomorrow morning the
winds will pick up an increasingly southerly component. VFR
throughout.
HJS
&&
.PREV DISCUSSION...
ISSUED 314 AM CDT Sat May 17 2014
SHORT TERM...Today through Monday
Upper low that has plagued the Great Lakes/Midwest for the past
several days will begin to lose its influence on the weather
today as it slowly lifts northeastward into Canada. Still plenty
of cold air aloft and weak cyclonic flow, so am expecting a robust
diurnal CU field and perhaps a few showers. HRRR is most
aggressive with developing precip furthest west into central
Illinois, while the NAM/GFS/ECMWF all tend to limit QPF to just
the far NE KILX CWA. Will follow the consensus here, keeping low
chance POPs for showers confined mainly along and northeast of a
Bloomington to Paris line in closer proximity to exiting upper
low. Given rising heights and increased sunshine, temps will be
quite a bit warmer than yesterday, with NAM forecast soundings
suggesting highs in the lower 60s.
After a clear/chilly night tonight with lows in the upper 30s and
lower 40s, ample sunshine will boost highs well into the 60s on
Sunday. Warming trend will continue into Monday, as upper wave
digs southward west of the Rockies, producing downstream ridging
across the central and eastern CONUS. As surface high pressure
shifts off to the east and low-level flow becomes more southerly,
high temps will return to near normal for this time of year in the
lower to middle 70s by Monday.
LONG TERM...Tuesday through Friday
A warmer and more unsettled pattern will develop in the extended.
A piece of energy from the western CONUS upper low will eject
eastward along the US/Canadian border, gradually flattening the
ridge across the Midwest. This will push a weak cold front
southward into central Illinois by the middle of next week. Model
solutions still vary on how far south this front will drop, but
with both the GFS and ECMWF advertising a strong 598dm 500mb high
developing along the Gulf Coast, do not think boundary will make
it too far south. As such, expect front to sag southward into
central Illinois on Wednesday, then become nearly stationary
through the end of the week. Given high heights and southerly
flow, high temperatures will reach the 80s on both Tuesday and
Wednesday, then will settle back into the 70s for Thursday and
Friday as the front tends to sink a bit further south toward the
Ohio River. Scattered showers and thunderstorms will develop in
the vicinity of the boundary beginning on Wednesday and persisting
through at least Thursday night. Latest runs of both the GFS and
ECMWF would suggest precip chances may need to be extended into
next weekend as front makes little or no southward progress.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1101 AM CDT SAT MAY 17 2014
.DISCUSSION...
331 AM CDT
AFTER THE INCREDIBLY LATE TASTE OF WINTER FOR PARTS OF THE AREA ON
FRIDAY...A FAIRLY QUIET WEATHER PATTERN IS SHAPING UP ALONG WITH A
NICE WARMING TREND INTO NEXT WEEK. THERE ARE NO SIGNIFICANT FORECAST
CONCERNS AFTER A WEEK AND A HALF OR SO OF ACTIVE WEATHER...THOUGH
THERE ARE SOME PERIODIC CHANCES FOR TSRA IN THE EXTENDED FORECAST
PERIOD. ADDITIONAL MINOR CONCERN IS WHICH DAYS ARE MOST FAVORED FOR
LAKE COOLING.
SHORT TERM...TODAY THROUGH MONDAY NIGHT
W/V IMAGERY THIS MORNING SHOWS ANOMALOUSLY DEEP UPPER TROUGH OVER
EASTERN NOAM. AGAIN SOME INCREDIBLY COLD 500 MB AND 850 MB TEMPS ON
THE 00Z RAOBS FOR THIS TIME OF YEAR...WITH -29C AT H5 AT KGRB AND
KILN AND -2C AT DVN AT H85. AT THE SURFACE...WEAK PRESSURE GRADIENT
ACROSS THE REGION AND SURFACE HIGH CENTERED OVER THE CENTRAL PLAINS.
TODAY AND TONIGHT...IT WILL BE A CHILLY START TO THE DAY WITH PARTLY
CLOUDY SKIES AND PATCHY TO AREAS OF FROST AND PATCHY GROUND FOG. THE
VERY COLD MIDLEVEL TEMPERATURES OVER THE AREA WILL SUPPORT A RAPID
BLOSSOMING OF FAIRLY HIGH-BASED STRATOCUMULUS BY MID TO LATE MORNING
OVER MUCH OF THE AREA AS LAPSE RATES STEEPEN. SOUNDINGS SHOW SOME
AVAILABLE CAPE DUE TO STEEP MIDLEVEL LAPSE RATES BUT LARGE T/TD
SPREADS AND OVERALL FORCING BEING FOCUSED MAINLY EAST OF THE AREA
THROW SOME DOUBT IN MUCH MORE THAN ISOLATED SHRA COVERAGE FROM BKN
STRATOCU DECK. THUS LOWERED POPS SOME INTO THE SLIGHT CHANCE RANGE.
WEAK WAA ALOFT DURING AFTN SUPPORTS HIGHS MOST AREAS REACHING NEAR
OR AROUND 60 DEGREES BASED ON 850/925 MB CLIMO. A WEAK LAKE BREEZE
MAY MAKE IT ONSHORE INTO CHICAGO AND PARTS OF NW IN SHORE DURING
AFTN AND KEEP THINGS SLIGHTLY COOLER THERE. DIURNALLY DRIVEN
STRATOCU SHOULD SCATTER OUT BY EARLY THIS EVENING...SETTING THE
STAGE FOR ANOTHER CHILLY NIGHT WITH LOWS IN UPPER 30S AND LOW 40S
OUTSIDE OF CHICAGO. SURFACE HIGH WILL BE SETTLING OVER EASTERN OH
VALLEY BY SUNDAY MORNING BUT WEAK GRADIENT WILL PREVENT SOUTHERLY
WINDS FROM INCREASING AND KEEPING TEMPS WARMER.
SUNDAY...SHAPING UP TO BE A GREAT DAY FOR OUTDOOR ACTIVITIES. OTHER
THAN SOME CIRRUS AND FAIR WEATHER CU...EXPECT PLENTY OF SUNSHINE AND
HIGHS JUST BELOW NORMAL INTO THE UPPER 60S. BUMPED UP TEMPERATURES
SLIGHTLY FROM PREVIOUS FORECAST ACCOUNTING FOR DRY AIR MASS BEING
CONDUCIVE TO MAXIMIZE HEATING BY SUN AS WELL AS CLOSER TO 925 MB
CLIMO. A WEAK LAKE BREEZE COULD PUSH ONTO PORTION OF SHORE BY LATE
AFTERNOON BUT LIKELY TOO LATE TO IMPACT HIGH TEMPERATURES.
MONDAY AND MONDAY NIGHT...WARM ADVECTION WILL CONTINUE TO INCREASE
DUE TO MIDLEVEL HEIGHT RISES. A FAIRLY DEEP UPPER TROUGH NEAR THE
WEST COAST WILL FORCE DOWNSTREAM RIDGING ACROSS THE MIDWEST. MID AND
HIGH CLOUDS ARE EXPECTED TO INCREASE FROM THE WEST DURING THE
AFTERNOON IN THE WARM ADVECTION PATTERN...BUT ACTUAL SHOWER ACTIVITY
LIKELY TO REMAIN WEST OF THE CWA. TEMPERATURES WILL WARM A FEW MORE
DEGREES TO AROUND 70/LOW 70S. THE EXCEPTION WILL BE THE IL LAKEFRONT
BASICALLY FROM DOWNTOWN CHICAGO AND NORTH WHICH WILL BE KEPT COOLER
IN THE LOWER 60S BY PERSISTENT SOUTHEAST COMPONENT TO THE WINDS.
GUIDANCE IS CONSISTENT ON A STRONG LOW LEVEL JET DEVELOPING MONDAY
NIGHT IN ADVANCE OF SURFACE LOW PRESSURE ACROSS THE PLAINS. NOSE OF
THE JET AND BEST CONVERGENCE SHOULD BE MAINLY NORTH OF CWA...BUT
CANNOT RULE OUT SOME SHRA DEVELOPMENT FOR NORTHERN 2/3 OF CWA. STEEP
LAPSE RATES FROM EML BEING ADVECTED OVER REGION...SO MENTIONED
SLIGHT CHANCE FOR TSRA.
LONG TERM...TUESDAY THROUGH FRIDAY...
850/925 MB TEMPS ARE PROGGED TO SOAR INTO THE MID TO HIGH TEENS
ON TUESDAY...SO MANY AREAS HAVE A GOOD SHOT TO REACH OR EXCEED 80
BY A FEW DEGREES EVEN WITH POTENTIAL FOR ONLY PARTIAL SUNSHINE.
FAR NORTHEAST IL COULD STILL BE KEPT COOLER BY SLIGHT SOUTHEAST
COMPONENT TO WIND THERE. FORECAST SOUNDINGS SHOW THAT ATMOSPHERE
COULD REMAIN LARGELY CAPPED TO CONVECTION UNLESS A MIDLEVEL WAVE
IS STRONG ENOUGH TO BREAK CAP. HOWEVER FOR NOW MAINTAINED GUIDANCE
BLEND SLIGHT TO LOW CHANCE POPS.
BETTER CHANCE FOR CONVECTION OVER NORTHERN HALF OF CWA WILL COME
WITH APPROACH OF SURFACE COLD FRONT TUESDAY EVENING NIGHT. GUIDANCE
IN DECENT AGREEMENT IN FRONTAL BOUNDARY ONLY SLOWLY PROGRESSING
SOUTH WEDNESDAY AND THURSDAY AND ELEVATED FRONT LAGGING EVEN MORE.
THUS THERE COULD BE SOME CONVECTIVE ACTIVITY INTO SOUTHERN HALF TO
THIRD OF CWA DURING THAT PERIOD...WITH BETTER CHANCE IN FAR SOUTH
CLOSER TO FRONTAL BOUNDARY. WEDNESDAY WILL BE ANOTHER WARM DAY FOR
MOST OF THE AREA WITH HIGHS IN UPPER 70S TO LOW 80S INLAND. THIS IS
DESPITE THE COLD FRONT LIKELY TO HAVE PUSHED INTO SOUTHERN CWA.
THE EXCEPTION TO THE WARMTH WILL BE THE LAKEFRONT AS A LAKE BREEZE
WILL DEVELOP EARLY AND KEEP TEMPERATURES 10 OR MORE DEGREES
COOLER. THURSDAY WILL BE SIMILAR BUT LIKELY NOT QUITE AS WARM
INLAND. NEXT FRIDAY IT APPEARS THAT SURFACE HIGH WILL BE OVER
WESTERN LAKES...WHICH SHOULD FAVOR DRY FORECAST. TEMPERATURES
SHOULD BE NEAR TO SLIGHTLY BELOW SEASONABLE INLAND BUT AGAIN
SEVERAL DEGREES COOLER NEAR THE LAKE.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SLIGHT CHANCE OF -SHRA THIS AFTERNOON.
//DISCUSSION...UPDATED 12Z...
WHILE THE UPPER LOW THAT BROUGHT SNOW TO SOME OF THE AREA
AIRPORTS YESTERDAY HAS NOW SHIFTED EAST...COLD TEMPERATURES ALOFT
WILL SUPPORT THE BLOSSOMING OF CUMULUS/STRATOCUMULUS LATE THIS
MORNING INTO AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE...BUT
COVERAGE SHOULD BE MUCH LESS THAN FRIDAY AFTERNOON. LIGHT
SOUTHWEST WINDS WILL INCREASE IN SPEED AS MIXING ENSUES AND SHOULD
BE ENOUGH TO PREVENT A LAKE BREEZE FROM REACHING MOST OF THE
CHICAGOLAND TAF SITES. THE EXCEPTION WOULD BE GARY WHERE WINDS MAY
BRIEFLY TURN NORTH/NORTHEAST DURING THE AFTERNOON HOURS. WINDS
WILL LIGHTEN SOME TONIGHT BEFORE INCREASING SUNDAY MORNING FROM
THE SOUTHWEST. ALL IN ALL...NO IMPACTS TO AVIATION EXPECTED.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH THAT IF ANY -SHRA OCCURS AT THE AIRFIELD IT WILL BE BRIEF.
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR.
MONDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA DURING THE NIGHT.
TUESDAY...EAST FLOW POSSIBLE. CHANCE OF TSRA.
WEDNESDAY...EAST FLOW.
THURSDAY...EAST FLOW. SLIGHT CHANCE OF TSRA DURING THE NIGHT.
FRIDAY...EAST FLOW.
MTF
&&
.MARINE...
212 AM CDT
WEAK LOW PRESSURE WILL MOVE EASTWARD JUST NORTH OF THE GREAT
LAKES TODAY WHICH WILL ACT TO TIGHTEN THE PRESSURE
GRADIENT...NAMELY OVER THE NORTHERN TWO-THIRDS OR SO. DID END UP
INCREASING SPEEDS/GUSTS A FEW KNOTS BASED ON THIS. THE LOW
BASICALLY WASHES OUT THOUGH THE PRESSURE GRADIENT ACROSS THE LAKE
LOOKS TO HOLD ITS OWN THROUGH THE WEEKEND...AS HIGH PRESSURE
BECOMES STATIONARY OVER THE OHIO RIVER VALLEY AND LOW PRESSURE
DEVELOPS ACROSS THE HIGH PLAINS. THIS WILL SPELL CONTINUED
SOUTHERLY FLOW FOR THE LAKE ON MONDAY AND TUESDAY. THE LOW
PRESSURE ORIGINATING IN THE PLAINS LOOKS TO MOVE ACROSS THE
NORTHERN LAKES ON LATE TUESDAY OR EARLY WEDNESDAY...WHICH WOULD
FAVOR A COOL FRONT PASSAGE NEAR THAT TIME...TURNING WINDS WESTERLY
AND THEN NORTHWEST OR NORTH DURING THE LATTER HALF OF THE WEEK.
THIS WOULD LOOK TO RESULT IN AT LEAST CLOSE TO SMALL CRAFT
ADVISORY WAVE CONDITIONS FOR THE INDIANA AND POSSIBLY ILLINOIS
NEARSHORE AREAS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1048 AM CDT Sat May 17 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sat May 17 2014
A little bit of a cyclonic turn to the winds still as the upper
trof slowly moves out of the Midwest. But between that and plenty
of moisture at llvls, cu field filling in on sat imagery this
morning. Some of those cu starting to get a bit heavy and showing
up on radar. There is a moderate amount of dry air to help cut
down overall precip accumulations, but activity is likely to be
very isolated anyway. Have expanded the iso mention, but no large
scale updates are anticipated at this time.
HJS
&&
.AVIATION...
ISSUED 640 AM CDT Sat May 17 2014
Residual moisture from the rain last evening and heavy dew/patchy
frost was creating shallow ground fog in spots early this morning,
especially at KPIA where the visibility has varied between 1/2 and
10 SM. Will go with MIFG at KPIA until 14z before plenty of sun will
eventually warm up the ground and help dissipate the fog. KCMI
could be similar, although it appears that MVFR visibility will
prevail there.
From mid-morning and beyond, the moisture profiles on the RAP and
the cloud base forecasts on the HRRR indicate the development of
additional high based CU around 5-7 kft ahead of another in a
series of shortwave troughs rotating toward the base of the upper
trough axis in Indiana.
There could be just enough instability for a few showers to
develop in east central IL, but the coverage and probability of
occurrence precludes a mention of VCSH in the TAFs for KBMI and
KCMI.
High pressure and rapidly increasing stability this evening will
give us a clear sky and very light wind from just before sunset
through daybreak Sunday.
Miller
&&
.PREV DISCUSSION...
ISSUED 314 AM CDT Sat May 17 2014
SHORT TERM...Today through Monday
Upper low that has plagued the Great Lakes/Midwest for the past
several days will begin to lose its influence on the weather
today as it slowly lifts northeastward into Canada. Still plenty
of cold air aloft and weak cyclonic flow, so am expecting a robust
diurnal CU field and perhaps a few showers. HRRR is most
aggressive with developing precip furthest west into central
Illinois, while the NAM/GFS/ECMWF all tend to limit QPF to just
the far NE KILX CWA. Will follow the consensus here, keeping low
chance POPs for showers confined mainly along and northeast of a
Bloomington to Paris line in closer proximity to exiting upper
low. Given rising heights and increased sunshine, temps will be
quite a bit warmer than yesterday, with NAM forecast soundings
suggesting highs in the lower 60s.
After a clear/chilly night tonight with lows in the upper 30s and
lower 40s, ample sunshine will boost highs well into the 60s on
Sunday. Warming trend will continue into Monday, as upper wave
digs southward west of the Rockies, producing downstream ridging
across the central and eastern CONUS. As surface high pressure
shifts off to the east and low-level flow becomes more southerly,
high temps will return to near normal for this time of year in the
lower to middle 70s by Monday.
LONG TERM...Tuesday through Friday
A warmer and more unsettled pattern will develop in the extended.
A piece of energy from the western CONUS upper low will eject
eastward along the US/Canadian border, gradually flattening the
ridge across the Midwest. This will push a weak cold front
southward into central Illinois by the middle of next week. Model
solutions still vary on how far south this front will drop, but
with both the GFS and ECMWF advertising a strong 598dm 500mb high
developing along the Gulf Coast, do not think boundary will make
it too far south. As such, expect front to sag southward into
central Illinois on Wednesday, then become nearly stationary
through the end of the week. Given high heights and southerly
flow, high temperatures will reach the 80s on both Tuesday and
Wednesday, then will settle back into the 70s for Thursday and
Friday as the front tends to sink a bit further south toward the
Ohio River. Scattered showers and thunderstorms will develop in
the vicinity of the boundary beginning on Wednesday and persisting
through at least Thursday night. Latest runs of both the GFS and
ECMWF would suggest precip chances may need to be extended into
next weekend as front makes little or no southward progress.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
115 PM EDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 115 PM EDT SAT MAY 17 2014
OTHER THAN SOME MINOR TWEAKS TO ACCOUNT FOR LATEST OBSERVATIONAL
TRENDS WILL MAKE FEW CHANGES TO THE FORECAST VALID FOR THE REMAINDER
OF THE AFTERNOON. SOMERSET REPORTED SOME BRIEF LIGHT RAIN AND WILL
CONTINUE WITH THE ISOLATED SHOWER THREAT FOR THE REST OF THE DAY IN
THE SOUTH. WILL ALSO CONTINUE WITH THE ISOLATED SHOWER THREAT IN THE
EXTREME NORTH AS ISOLATED SHOWERS CONTINUE IN FAR NORTHERN KY...SE
INDIANA AND SOUTHERN OH.
UPDATE ISSUED AT 1017 AM EDT SAT MAY 17 2014
UPDATED NDFD AND ASSOCIATED FORECAST PRODUCTS BASED ON LATEST
ANALYSIS AND TRENDS. WILL CONTINUE TO CARRY ISOLATED SHOWERS IN THE
FAR SOUTH THIS AFTERNOON AS STILL SEEING SOME RADAR RETURNS OVER FAR
SOUTH CENTRAL KY. THERE HAS BEEN 0.01 INCH AT THE TODD COUNTY
MESONET SITE THIS MORNING...SO VERY LOW END MEASURABLE RAIN IS
POSSIBLE. HAVE ALSO ADDED ISOLATED SHOWERS OVER THE FAR NORTHERN
PART OF THE FORECAST AREA...MAINLY JUST FLEMING COUNTY. MORNING SOUNDINGS
SHOW COLDEST MID LEVEL TEMPERATURES OVER OH INTO FAR NORTHERN
KY...AND ENOUGH INSTABILITY EXISTS FOR SHOWERS. SCATTERED SHOWERS
ALREADY ON RADAR OVER SOUTHERN OH...AND IT IS POSSIBLE THAT SOME
SHOWERS MAY CLIP OUR FORECAST AREA. THIS IDEA IS SUPPORTED BY THE
LATEST HRRR GUIDANCE. OTHER UPDATED ELEMENTS INCLUDED SKY COVER...AS
THE CLOUD COVER WILL HOLD LONGER IN THE SOUTH...AND MAY BE A LITTLE
MORE EXTENSIVE IN THE NORTH WHERE IT WILL BE MORE CONVECTIVE IN
NATURE. THE CENTRAL PART OF THE FORECAST AREA SHOULD HAVE THE MOST
SUNSHINE THIS AFTERNOON. FINALLY MADE SOME MINOR ADJUSTMENTS TO
TEMPERATURES DUE TO THE SKY COVER ADJUSTMENTS.
UPDATE ISSUED AT 752 AM EDT SAT MAY 17 2014
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND SKY COVER
ACCORDING TO THE LATEST TRENDS IN OBSERVATIONS. THICKER MID-LEVEL
CLOUD COVER HAS EDGED A BIT MORE NORTH EARLY THIS MORNING...ALTHOUGH
THE NORTHERN PERIPHERY OF THE SHIELD SHOULD BURN OFF SOMEWHAT LATER
THIS MORNING. OTHERWISE...THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 335 AM EDT SAT MAY 17 2014
THE LATEST SURFACE MAP FEATURES BROAD HIGH PRESSURE SPRAWLED ACROSS
THE CENTRAL PLAINS...WITH ANOTHER HIGH CENTERED ACROSS THE DEEP
SOUTH. LOW PRESSURE REMAINS POISED ACROSS NM/TX...WITH AN INVERTED
TROUGH NOSING IN THROUGH THE TENNESSEE VALLEY...SEPARATING THE
AFOREMENTIONED TWO HIGH PRESSURE AREAS. ALOFT...AN UPPER LEVEL LOW
IS SPIRALING ACROSS ONTARIO...LEAVING THE OHIO VALLEY AND GREAT
LAKES REGIONS IN AN UNSEASONABLY COOL AIR MASS. TEMPERATURES ACROSS
EASTERN KENTUCKY ARE CURRENTLY RANGING FROM 36 TO 41 DEGREES...WITH
AREAS OF DENSE VALLEY FOG SHOWING UP NICELY ON SATELLITE.
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH
CYCLONIC FLOW GRADUALLY EASING UP ACROSS THE OHIO AND TENNESSEE
VALLEYS...AS THE CANADIAN UPPER LOW FILLS AND THE ASSOCIATED TROUGH
SHIFTS EAST...WITH UPPER LEVEL RIDGING WORKING IN FROM THE WEST.
A SHORT WAVE TROUGH CURRENTLY MOVING THROUGH MISSOURI WILL MOVE INTO
THE TENNESSEE VALLEY TODAY...PROVIDING A FOCUS FOR SOME SHOWER
ACTIVITY GENERALLY SOUTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80
CORRIDORS. THIS WAVE IS MUCH TAMER COMPARED TO FRIDAY...SO ONLY
ISOLATED COVERAGE IS EXPECTED. FURTHER NORTH...EXPECTING MAINLY JUST
A GOOD CUMULUS FIELD TO BUILD IN...WITH PERHAPS A STRAY SPRINKLE OR
LIGHT SHOWER POSSIBLE DURING PEAK HEATING. HIGHS WILL AVERAGE A GOOD
15 DEGREES BELOW NORMAL...GENERALLY AROUND THE 60 DEGREE MARK.
SKIES WILL BE SLOW TO CLEAR IN THE SOUTH TONIGHT...LIKELY KEEPING THE
PATCHY FROST POTENTIAL IN CHECK. FURTHER NORTH THERE WILL BE BETTER
POTENTIAL FOR SOME PATCHY FROST...AS TEMPERATURES LOOK TO DROP INTO
THE MID 30S IN THE COLDEST SPOTS ONCE AGAIN...WITH MORE SUSTAINED
CLEARING TAKING PLACE. FOG WILL ALSO BE PREVALENT ONCE AGAIN AS WELL.
SUNDAY WILL BE DRY WITH MORE SUNSHINE...AS THE TROUGH SHIFTS FURTHER
EAST. HIGHS WILL REBOUND INTO THE MID AND UPPER 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM EDT SAT MAY 17 2014
OVERALL MEAN FLOW WILL CONTINUE TO EVOLVE INTO A BLOCKING PATTERN
WITH A DEEP TROUGH OVER THE SOUTHWEST U.S...RIDGING OVER THE SOUTH
CENTRAL TO SOUTHEAST PART OF THE COUNTRY AND TROUGHING OVER THE
NORTHEAST. THE FROST POTENTIAL WILL CONTINUE SUNDAY NIGHT FOR VALLEY
LOCATIONS AND OTHER TYPICALLY COOL SPOTS...WITH SURFACE HIGH
PRESSURE OVER THE UPPER OH VALLEY...AND MOSTLY CLEAR SKIES AND LIGHT
WINDS. SOME VALLEY LOCATIONS COULD DROP INTO THE UPPER 30S BY MONDAY
MORNING. WE WILL SEE A WARMING TREND EARLY NEXT WEEK AS UPPER LEVEL
RIDGING BEGINS TO BUILD INTO THE SOUTH CENTRAL U.S. AND HEIGHTS RISE
ACROSS THE OHIO VALLEY. MONDAY WILL MARK THE START OF THE WARM UP IN
THE EXTENDED...AS HIGHS ARE EXPECTED TO RISE TO AROUND 70 DEGREES
ACROSS THE AREA. DAYTIME MAXIMUM TEMPERATURES WILL TOP OUT IN THE
UPPER 70S AND LOWER 80S THE REST OF THE WEEK AS THE RIDGE
STRENGTHENS. EASTERN KENTUCKY WILL REMAIN ON THE NORTHEAST PERIPHERY
OF THE UPPER LEVEL RIDGE...AND REMAIN SUSCEPTIBLE TO PERIODS OF
SHOWERS AND STORMS FROM MIDWEEK ON. A SURFACE BOUNDARY MAY ALSO
BECOME NEARLY STATIONARY ACROSS THE AREA BY LATE IN THE WEEK FURTHER
ENHANCING PRECIPITATION CHANCES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 115 PM EDT SAT MAY 17 2014
VFR CONDITIONS WILL PREVAIL AT THE TAF SITES THROUGH THE FORECAST
PERIOD. FOR THE REMAINDER OF THIS AFTERNOON CEILINGS OF 5K TO 7K
FEET WILL PREVAIL ACROSS THE AREA...WITH OVC CEILINGS IN THE
SOUTH...AND BKN CEILINGS IN THE CENTRAL AND NORTH. ISOLATED MVFR
CEILINGS WILL BE POSSIBLE IN THE FAR NORTHERN PART OF THE FORECAST
AREA CLOSER TO THE OH RIVER AND WELL NORTH OF THE TAF SITES.
CLOUDS WILL DECREASE IN COVERAGE THIS EVENING BUT SHOULD INCREASE
AGAIN IN THE SOUTH AS ANOTHER UPPER LEVEL DISTURBANCE MOVES ACROSS TN.
CLOUDS SHOULD LIMIT FOG FORMATION IN THE SOUTH TONIGHT...WITH FOG
FORMATION ELSEWHERE MAINLY LIMITED TO RIVER AND CREEK VALLEYS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...GEOGERIAN
LONG TERM...SBH/AR
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS GRAY ME
1241 PM EDT SAT MAY 17 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY THROUGH THE FORECAST AREA TODAY.
THIS FRONT WILL THEN BECOME STATIONARY IN EASTERN MAINE. UPPER
LEVEL LOW PRESSURE WILL THEN MOVE OVERHEAD BY MONDAY AND REMAIN
NEAR THE AREA THROUGH THE WEEK RESULTING IN AN UNSETTLED WEATHER.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE 2...WILL ADJUST POPS, SKY COVER, AND TEMPS AS CLEARING
CONTINUE TO MOVE IN FROM THE SOUTHWEST AND RAIN IS GOING TO EXIT
THE FORECAST AREA IN THE NEXT 1 TO 2 HOURS. FLOOD WARNINGS ARE NOW
IN EFFECT FOR THE SWIFT RIVER WHICH IS CRESTING NOW AND THE PEMI
AT WOODSTOCK AND PLYMOUTH.
UPDATE...HAVE UPDATE FORECAST POPS AND TEMPS. PRECIPITATION ENDING
FROM SOUTHWEST TO NORTHEAST AND CLOUDS CLEARING ALSO IN SW NEW HAMPSHIRE.
HAVE ISSUED A FLOOD WARNING FOR THE PEMIGEWASSET RIVER AT
WOODSTOCK.
PREV DISC...
SHOWERS CONTINUE TO FORM AND RACE INTO MAINE OFF THE GULF OF
MAINE DURING THE EARLY MORNING HOURS. LARGER BAND OF CONVECTION
WITH THE ASSOCIATED COLD FRONT WILL MOVE EAST THIS
MORNING...REACHING THE PORTLAND AREA BY AROUND 09Z AND CLEARING
THIS SAME REGION AROUND 14Z PER LATEST HRRR MODEL PROJECTS.
THEREFORE...THE HIGHEST POPS WILL BE IN DURING THE EARL TO MID
MORNING HOURS. NO SIGNIFICANT WIND SHIFT TIL LATER IN THE DAY...SO
CLEARING WILL BE CONFINED TO NEW HAMPSHIRE AND FAR WESTERN MAINE
LATER TODAY.
USED BLEND OF MESO MODEL DATA FOR AFTERNOON HIGH TEMPS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
CLEARING CONTINUES FROM WEST TO EAST TONIGHT INTO SUNDAY...WITH
THE MOST CLOUDINESS HANGING TOUGH IN THE UPSLOPE TERRAIN OF THE
WESTERN MOUNTAINS OF MAINE AND NORTHERN NEW HAMPSHIRE.
OTHERWISE...DESPITE PRESENCE OF UPPER LEVEL TROUGH ON
SUNDAY...FAVORABLE NORTHWEST WINDS WILL ALLOW FOR SOME SUNSHINE
AND MILD TEMPERATURES. THERE WILL BE A SLIGHT CHANCE FOR A SHOWER
WHERE MOISTURE WILL ACCOMPANY LIMITED DYNAMICS OVER EASTERNMOST
PORTIONS OF THE FORECAST AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
AN UPPER CYCLONIC FLOW EARLY IN THE WEEK WILL ALLOW DIURNAL SCT
SHWRS TO DEVELOP EACH AFTN AS HEATING OCCURS. A WEAK RIDGE TRIES TO
BUILD OVER THE REGION BRIEFLY LATE TUE AND WED BUT STILL WITH A
CHC OF SHWRS. ANOTHER UPPER LOW WITH ITS CYCLONIC FLOW AND
INSTBLTY WILL ONCE AGAIN GET CARVED OUT OVER THE NORTHEAST LATER
IN THE WEEK ALLOWING MORE INSTBLTY SHWRS. TEMPS WILL BE NEAR
SEASONAL LEVELS THROUGH THE WEEK.
USED THE SUPERBLEND FOR POPS AND TEMPS.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...AREAS OF IFR AND LIFR CONDITIONS THIS
MORNING...FOLLOWED BY IMPROVING CONDITIONS TO VFR.
LONG TERM...MAINLY VFR CONDS BUT LOWERING TO MVFR IN SCT SHWRS.
&&
.MARINE...
SHORT TERM...SCA TO REMAIN IN PLACE FOR SEAS.
LONG TERM...WINDS/SEAS TO REMAIN BLO SCA CRITERIA.
&&
.FIRE WEATHER...
RAIN AND WETTING CONDITIONS WILL KEEP FUELS MOIST.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ150>154.
&&
$$
TFH
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
135 PM EDT SAT MAY 17 2014
.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL PERSIST OVER THE EASTERN STATES
THROUGH SUNDAY WHILE SURFACE HIGH PRESSURE BUILDS OVER THE REGION.
HIGH PRESSURE REMAINS OVERHEAD THROUGH MONDAY BEFORE MOVING OFF
THE COAST TUESDAY. A COLD FRONT WILL APPROACH THE REGION WEDNESDAY
BEFORE PASSING THROUGH WEDNESDAY NIGHT INTO THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A FROST ADVISORY IS IN EFFECT FOR PORTIONS OF THE ALLEGHENY FRONT
AND CENTRAL FOOTHILLS LATE TONIGHT. PARTIAL CLEARING AND CALM
WINDS WILL LEAD TO TEMPERATURES DROPPING TO THE MID 30S IN THIS
AREA AND FROST MAY FORM IN THESE CONDITIONS.
AN UPPER LEVEL TROUGH IS LOCATED ACROSS THE GREAT LAKES THIS
MORNING. MULTIPLE DISTURBANCES ARE ROTATING AROUND THE BASE OF THE
TROUGH AND WILL APPROACH THE REGION TODAY AND TONIGHT. HIGH
PRESSURE WILL APPROACH THE REGION FROM THE MIDWEST TODAY.
SUNSHINE WILL CONTINUE THIS MORNING BEFORE CLOUDS INCREASE FROM
THE WEST THIS AFTERNOON. A DISTURBANCE WILL CROSS THE REGION THIS
MORNING FROM THE TN VALLEY WHILE ANOTHER DISTURBANCE CROSSES WV
AND PA THIS AFTERNOON. A CU FIELD WILL DEVELOP ACROSS THE AREA AS
DAYTIME HEATING CONTINUES AND MIXING TO 80-75MB IS EXPECTED. NAM
AND RAP FCST SOUNDINGS HAVE ABOUT 30-50 J/KG BELOW THE CAPPING
INVERSION THIS AFTERNOON. A FEW SHOWERS MAY FORM ACROSS NRN
MD..NOVA AND THE BALTIMORE METRO CLOSER TO THE UPPER LEVEL
DISTURBANCE TO THE NORTH AND WEST. DRY CONDITIONS AT THE SFC WILL
LEAD TO SPRINKLES AND VIRGA TO OCCUR HENCE KEEPING THE FCST DRY
THIS AFTERNOON.
PREVIOUS FORECAST...
HIGH PRESSURE WILL BUILD OVERHEAD TONIGHT...BRINGING DRY AND COOL
CONDITIONS. AN UPPER-LEVEL DISTURBANCE ROTATING AROUND THE TROUGH
MAY BRING SOME MID-LEVEL CLOUDS. MIN TEMPS WILL RANGE FROM THE MID
30S IN SOME OF THE COLDER SPOTS OF THE ALLEGHENY AND POTOMAC
HIGHLANDS TO THE LOWER AND MIDDLE 50S IN DOWNTOWN WASHINGTON AND
BALTIMORE. PATCHY FROST MAY DEVELOP OVER PORTIONS OF THE ALLEGHENY
AND POTOMAC HIGHLANDS. NOT CONFIDENT ENOUGH FOR AN ADVISORY AT
THIS TIME DUE TO A LIGHT GRADIENT WIND AND A POSSIBLE BKN STRATOCU
DECK ALONG AND WEST OF THE ALLEGHENY FRONT.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH SUNDAY
NIGHT WHILE AN UPPER-LEVEL TROUGH REMAINS OVERHEAD. LIMITED
INSTABILITY WILL RESULT IN ANOTHER BKN CU DECK SUNDAY WITH PERHAPS
A FEW SPRINKLES ACROSS THE NORTHERN AND WESTERN PORTIONS OF THE
CWA. HOWEVER...MOST AREAS WILL TURN OUT DRY DUE TO A DOWNSLOPING
NORTHWEST FLOW AND PLENTY OF LOW-LEVEL DRY AIR. MAX TEMPS SUNDAY
WILL REMAIN A FEW DEGREES BELOW CLIMO...RANGING FROM UPPER 50S
AND LOWER 60S IN THE MOUNTAINS TO THE LOWER 70S IN DOWNTOWN
WASHINGTON AND BALTIMORE.
RADIATIONAL COOLING IS EXPECTED SUNDAY NIGHT WITH HIGH PRESSURE
OVERHEAD ALONG WITH LIGHT WINDS...MAINLY CLEAR SKIES AND DRY AIR
IN PLACE. MIN TEMPS WILL RANGE FROM THE LOWER AND MIDDLE 30S IN
SOME OF THE COLDER LOCATIONS OF THE POTOMAC HIGHLANDS AND WESTERN
MARYLAND...TO THE LOWER 50S IN DOWNTOWN WASHINGTON AND BALTIMORE.
A FROST ADVISORY MAY BE NEEDED FOR PORTIONS OF THE POTOMAC
HIGHLANDS AND WESTERN MARYLAND.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THE UPPER-LEVEL TROUGH WILL SHIFT EAST MONDAY WHILE SURFACE HIGH
PRESSURE REMAINS OVERHEAD. MORE DRY CONDITIONS ARE EXPECTED ALONG
WITH SUNSHINE AND LOW RELATIVE HUMIDITY. MAX TEMPS WILL BE FEW
DEGREES WARMER COMPARED TO THE WEEKEND...CLOSER TO CLIMO.
THE SURFACE HIGH WILL MOVE OFF THE COAST TUESDAY AND A RETURN
SOUTHERLY FLOW WILL CAUSE MAX TEMPS TO BE A FEW DEGREES WARMER
ALONG WITH SOME SUNSHINE.
AN UPPER-LEVEL RIDGE WILL BUILD OVER THE SOUTHERN CONUS DURING THE
MIDDLE AND LATTER PORTIONS OF NEXT WEEK WHILE ANOTHER UPPER-LEVEL
LOW DEVELOPS OVER THE GREAT LAKES AND SHIFTS TOWARD NEW ENGLAND. A
NORTHWEST FLOW ALOFT WILL DEVELOP OVER OUR REGION IN BETWEEN THESE
SYSTEMS. THE COLD FRONT ASSOCIATED WITH THE UPPER-LEVEL LOW WILL
APPROACH OUR REGION WEDNESDAY INTO WEDNESDAY NIGHT BEFORE PASSING
THROUGH THURSDAY. THE NORTHWEST FLOW ALOFT ALONG WITH WARM AND
HUMID CONDITIONS AHEAD OF THE COLD FRONT WILL INCREASE THE CHANCE
FOR SHOWERS AND THUNDERSTORMS WEDNESDAY AND THURSDAY. THE FRONT
SHOULD STALL TO OUR SOUTH LATE NEXT WEEK ALLOWING FOR DRIER AND
LESS HUMID CONDITIONS TO RETURN.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. NORTHWEST WINDS WILL
GUST AROUND 15 KNOTS TODAY. A BKN CU DECK IS EXPECTED WITH CIGS
AROUND 5KFT THIS AFTERNOON. WINDS WILL BE LIGHT TONIGHT.
VFR CONDITIONS WILL CONTINUE THROUGH EARLY NEXT WEEK. AN
APPROACHING COLD FRONT MAY TRIGGER SOME SHOWERS AND THUNDERSTORMS
WEDNESDAY.
&&
.MARINE...
A WEAK PRESSURE SURGE IS EXPECTED THIS MORNING BEHIND A COLD
FRONT. A FEW ISOLATED GUSTS UP TO 20KTS ARE POSSIBLE THIS MORNING
ACROSS THE LOWER TIDAL POTOMAC AND MD CHESAPEAKE BAY SOUTH OF
SANDY POINT. THE PRESSURE SURGE IS WEAK AND IS ONLY EXPECTED THIS
MORNING AND THEREFORE SCA IS NOT IN EFFECT. NORTHWEST WINDS WILL
CONTINUE THIS AFTERNOON. ANOTHER WEAK PRESSURE SURGE WILL PASS
THROUGH THE WATERS TONIGHT AND NORTHWEST WINDS WILL BE CLOSE TO
SCA CRITERIA LATE TONIGHT INTO SUNDAY MORNING. GUSTS HAVE BEEN
CAPPED AROUND 15 KNOTS FOR NOW.
HIGH PRESSURE WILL BUILD OVER THE WATERS EARLY NEXT WEEK BEFORE
MOVING OFF THE COAST TUESDAY. A RETURN SOUTHERLY FLOW WILL DEVELOP
DURING THE MIDDLE PORTION OF NEXT WEEK.
&&
.HYDROLOGY...
AREAL FLOOD WARNINGS FOR CREEKS AND STREAMS CONTINUE TO DIMINISH AS
WATER FLOWS INTO THE MAIN STEM RIVERS. THESE WARNINGS WILL LIKELY
BE ALLOWED TO EXPIRE THIS MORNING.
RIVER FLOOD WARNINGS ARE IN EFFECT FOR MANY POINTS ALONG THE
SHENANDOAH...RAPPAHANNOCK... RAPIDAN AND POTOMAC...AND OTHER
TRIBUTARY RIVER BASINS. FLOODING WILL CONTINUE ON THE POTOMAC
UNTIL SUNDAY EVENING. PLEASE SEE LATEST FLOOD WARNINGS FOR FURTHER
DETAILS.
&&
.TIDES/COASTAL FLOODING...
A COASTAL FLOOD WARNING IS IN EFFECT FOR WASHINGTON DC AND
ALEXANDRIA ALONG THE UPPER TIDAL POTOMAC RIVER. FRESHWATER FLOW
WILL CONTINUE TO INCREASE FROM THE POTOMAC RIVER. THIS WILL CAUSE
MODERATE FLOODING AT ALEXANDRIA...AND GEORGETOWN. MODERATE FLOODING
IS EXPECTED AT GEORGETOWN AROUND HIGH TIDE TONIGHT.
MODERATE FLOODING WILL CONTINUE SUNDAY AND PERHAPS SUNDAY NIGHT.
SEE THE COASTAL FLOOD WARNING...WBCCFWLWX FOR FURTHER DETAILS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD WARNING UNTIL 6 AM EDT MONDAY FOR DCZ001.
MD...NONE.
VA...FROST ADVISORY FROM 4 AM TO 9 AM EDT SUNDAY FOR VAZ503-504.
COASTAL FLOOD WARNING UNTIL 6 AM EDT MONDAY FOR VAZ054.
WV...FROST ADVISORY FROM 4 AM TO 9 AM EDT SUNDAY FOR WVZ501-505-506.
MARINE...NONE.
&&
$$
SYNOPSIS...BJL
NEAR TERM...BJL/HAS
SHORT TERM...BJL
LONG TERM...BJL
AVIATION...BJL
MARINE...BJL
HYDROLOGY...
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 PM CDT SAT MAY 17 2014
.UPDATE...
ISSUED AT 1215 PM CDT SAT MAY 17 2014
UPDATE TO ADD LOW POPS SOUTHWEST...CENTRAL...AND NORTH CENTRAL
THIS AFTERNOON. ISOLATED SHOWERS HAVE POPPED UP THIS
AFTERNOON...WITH A LIGHTNING STRIKE NOTED IN TOWNER COUNTY. THE
COVERAGE OF ANY SHOWERS/BRIEF STORMS SHOULD REMAIN LOW AND NO
SEVERE WEATHER IS EXPECTED.
UPDATE ISSUED AT 936 AM CDT SAT MAY 17 2014
MORNING UPDATE TO ADD A LOW AFTERNOON POP ACROSS THE FAR NORTH.
HIGH RESOLUTION MODELS ARE SUGGESTING SOME POTENTIAL FOR A FEW
SHOWERS LATE. OTHER THAN A SMALL PATCH OF LINGERING LIGHT
FOG/STRATUS NEAR WILLISTON...EARLY MORNING FOG HAS DISSIPATED.
UPDATE ISSUED AT 619 AM CDT SAT MAY 17 2014
CLEAR SKIES AND LIGHT WINDS HAVE ALLOWED FOG TO DEVELOP ACROSS
PARTS OF NORTHWEST NORTH DAKOTA EARLY THIS MORNING. THE LATEST
HRRR CAPTURES THIS WELL...AND SHOWS THE FOG LIFTING QUICKLY THIS
MORNING. WILL ADD PATCHY FOG IN THE NORTHWEST FOR A COUPLE
HOURS...WITH MAINLY CLEAR SKIES ELSEWHERE. THE REMAINDER OF THE
FORECAST IS ON TRACK...AND MADE ONLY MINOR CHANGES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 309 AM CDT SAT MAY 17 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...NORTHWEST FLOW ALOFT REMAINS OVER THE NORTHERN PLAINS
REGION WITH EMBEDDED ENERGY STRETCHING FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS. WEAK HIGH PRESSURE ACROSS THE STATE
RESULTING IN LIGHT AND VARIABLE WINDS EARLY THIS MORNING. SCT-
BKN MID LEVEL CLOUDS NEAR THE MID LEVEL PVA FROM EASTERN MONTANA
THROUGH THE WESTERN DAKOTAS WITH MOSTLY CLEAR CONDITIONS CENTRAL
AND EAST.
WINDS WILL TAKE ON A MORE SOUTHERLY/WESTERLY COMPONENT ACROSS WEST
AND CENTRAL ND AS THE MORNING PROGRESSES WITH HIGH PRESSURE
DRIFTING TO OUR SOUTH. SFC RIDGE WILL REMAIN STRETCHED FROM
EASTERN SD BACK NORTHWEST ACROSS MY AREA THROUGH TODAY.
WHILE SOME MODELS TRY TO GENERATE QPF TODAY...HR MODELS SUCH AS
THE NESTED NAM AND RAP KEEP THINGS DRY. WITH THE SFC RIDGE IN
PLACE...LACK OF GOOD MID LEVEL ENERGY...AND THE UPPER JET PUSHING
OFF TO OUR SOUTH...DO NOT ANTICIPATE ANY PRECIPITATION SO WILL
REMAIN DRY. ALSO...CLOUD DECKS NEAR 8-10K FT AGL SHOULD PREVENT
ANY MEASURABLE PRECIPITATION OVER THE NEXT 24-36 HOURS EVEN IF A
MID LEVEL SHOWER DEVELOPS THIS SAT AFTERNOON/EVENING AS SOME OF
THE MODELS SUGGEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT SAT MAY 17 2014
SUNDAY SHOULD START DRY...BUT RAIN CHANCES WILL INCREASE ACROSS
WESTERN NORTH DAKOTA BY AFTERNOON AS A SURFACE TROUGH STRENGTHENS
ACROSS EASTERN MONTANA / WYOMING. IT APPEARS MUCH OF THE INITIAL
RAIN CHANCES WILL BE IN MONTANA AND WYOMING CLOSER TO THE SURFACE
FEATURE....BUT THE CHANCES SPREAD EAST LATE IN THE AFTERNOON AS
THE FIRST IN A SERIES OF UPPER WAVES MOVES INTO THE REGION.
INSTABILITY INCREASES SUNDAY AFTERNOON / EVENING IN WESTERN NORTH
DAKOTA WITH SBCAPE APPROACHING 1000 J/KG. DEEP LAYER SHEAR
APPROACHES 40-45 KTS...SO THINK AT LEAST A FEW STRONG STORMS ARE
POSSIBLE AND INCLUDED THE MENTION IN THE HAZARDOUS WEATHER
OUTLOOK. THIS ALSO LINES UP WELL WITH THE SPC DAY 2 COMBINED
SEVERE OUTLOOK PROBABILITIES.
THE THUNDERSTORM CHANCES SPREAD ACROSS WESTERN AND CENTRAL NORTH
DAKOTA SUNDAY NIGHT AS A 50 KT LOW LEVEL JET LIFTS INTO THE
REGION. THE MODELS ARE IN GOOD AGREEMENT REGARDING THE RAIN
CHANCES SUNDAY NIGHT...SO WILL KEEP POPS IN THE LIKELY CATEGORY.
MODEL UNCERTAINTY INCREASES ON MONDAY WITH DIFFERING SOLUTIONS
REGARDING THE PROGRESSION OF THE SURFACE LOW. OVERALL...IT APPEARS
THE MODELS ARE FAVORING LESS NEW SHOWER/THUNDERSTORM DEVELOPMENT
MONDAY AFTERNOON...AND CONFINE THE BEST CHANCES TO THE EASTERN
PORTION OF THE FORECAST AREA AS THE LOW MOVES THROUGH.
THE REMAINDER OF THE EXTENDED PERIOD WILL FEATURE PERIODIC WAVES
MOVING THROUGH WEAK RIDGING ACROSS THE NORTHERN PLAINS. THE LATEST
GFS AND ECMWF SHOW A BIT MORE INSTABILITY AVAILABLE THROUGH THE
WEEK...SO HAVE ADDED THUNDERSTORM CHANCES WHERE APPROPRIATE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1215 PM CDT SAT MAY 17 2014
A FEW SHOWERS...AND POSSIBLY AN ISOLATED THUNDERSTORM...ARE
EXPECTED THIS AFTERNOON. THE CHANCE OF ANY IMPACTS AT A PARTICULAR
AERODROME ARE LOW...AND HAVE LEFT PRECIP OUT OF THE 18Z TAFS.
OTHERWISE...EXPECT VFR CONDITIONS WITH LIGHT W/SW WINDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...NH
LONG TERM...CK
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
[top]
Area Forecast Discussion
National Weather Service Spokane WA
221 PM PDT SAT MAY 17 2014
.SYNOPSIS...
High pressure will continue to break down through tonight, while
low pressure migrates Inland for Sunday and early next week.
The weather will remain unsettled from this evening through the
first part of next week, with showers and a threat of
thunderstorms accompanying cooler temperatures. The shower threat
wanes and temperatures moderate towards the middle of next week.
&&
.DISCUSSION...
Tonight and tomorrow...A large area of low pressure continues to
influence the forecast area into tomorrow. Shortwave disturbance
rotating along the edges of this large upper level low have the
capability to eject northward in a negative tilt and utilize the
cool conditionally unstable airmass contained in the low to kick
off showers and possibly a thunderstorm or two primarily in the
afternoon and evening hours. Overnight hours could see a shower or
two if a strong enough shortwaves passes through but the most
current HRRR models are not too keen on it happening in any big
way. Otherwise as the center of the low drifts closer to the
region forecast temperatures will continue do show a slight
cooling trend which is most apparent in the forecast high
temperatures. /Pelatti
Sunday Nt through Tuesday: Sunday Nt and Monday will be similar
synoptic-wise as Ern Wa and N Idaho remain under a
shearing/weakening upper trough axis with tough to nail down
nearly mesoscale vort maxes embedded within the trough. This
regime still leads to a chance of showers and isolated
thunder...especially each afternoon. For Monday Nt and Tuesday...
short-wave ridging/rising heights aloft begin a stabilizing trend
across the zones near the Canadian border of Wa. However...most
guidance is also bringing a weak vort max south through the Idaho
Panhandle Monday Nt and Tues. Because of this, we continued the
threat of showers into Tues for all but the Upper Columbia Basin.
The CAPE/deep lyr shear profiles don`t look sufficient to produce
strong thunderstorms in this mostly diurnally-driven convection
pattern. bz
Tuesday night through Saturday...A westerly zonal flow pattern
will dominate the middle to end of the week. A flat ridge
Wednesday and Thursday should result in dry conditions except for
a slight chance of a few lingering showers over the Idaho
Panhandle mountains on Wednesday. For Friday and Saturday there is
good model agreement of a short wave tracking through the region
on Friday followed by possibly another one for Saturday. However
precise strength of these features are in question with not a lot
of model consistency. The ECMWF has been the stronger solution
over the past couple runs which would support higher
precipitation chances while the GFS would favor a chance for
mainly mountain showers. Given the uncertainty forecast favors
climatological chances for rain showers (ie 15-30% for most
areas). JW
&&
.AVIATION...
18z TAFS: Low pressure moving in from off the coast will continue
to influence the aviation area by streaming in not only middle
and high clouds but also advecting in some lower level moisture
and keeping the atmosphere somewhat unstable to allow for
convective showers and thunderstorms during late morning and into
the early evening. Regardless VFR conditions should prevail except
for perhaps brief MVFR ceilings and visibilities near and below
the more intense showers and thunderstorms. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 44 64 43 64 43 70 / 20 50 50 50 20 20
Coeur d`Alene 43 63 40 63 40 69 / 20 60 60 50 30 20
Pullman 43 62 41 64 40 67 / 20 60 50 40 20 20
Lewiston 48 68 46 71 44 72 / 20 50 40 30 20 20
Colville 42 68 41 67 41 76 / 40 60 60 50 30 20
Sandpoint 41 62 41 62 38 69 / 30 50 60 60 40 20
Kellogg 42 61 41 62 41 68 / 30 60 60 50 40 20
Moses Lake 46 72 46 72 46 77 / 10 20 20 30 10 0
Wenatchee 50 71 48 71 50 77 / 10 20 20 20 10 0
Omak 43 70 42 70 42 77 / 30 30 30 20 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
213 PM PDT SAT MAY 17 2014
.SYNOPSIS...AN UPPER LEVEL LOW WILL SLOWLY DRIFT CLOSER TO THE COAST
THIS WEEKEND FOR CONTINUED COOLER AND UNSETTLED WEATHER. THE CHANCE
OF SHOWERS WILL SLOWLY RISE THROUGH THE WEEKEND...WITH THE BEST
CHANCE OF SHOWERS FROM TONIGHT INTO MONDAY AS THE LOW MOVES CLOSER
AND THEN MOVES THROUGH THE FORECAST AREA. ISOLATED THUNDER IS
POSSIBLE DURING THIS PERIOD...ESPECIALLY SUNDAY AND MONDAY
AFTERNOONS. DRY AND MILDER WEATHER RETURNS IN THE MIDDLE OF NEXT WEEK
AS AN UPPER RIDGE MOVES INTO THE PACIFIC NORTHWEST.
&&
.SHORT TERM...AN UPPER LEVEL LOW IS LOCATED OVER THE NORTHEAST
PACIFIC THIS AFTERNOON...WITH A ITS CENTER WEST OF 130W. ONE WEAK
SHORT WAVE DISTURBANCE MOVED THROUGH THE PACIFIC NORTHWEST THIS
MORNING WITH SOME SPOTTY LIGHT PRECIPITATION. WE ARE IN BETWEEN
DISTURBANCES THIS AFTERNOON WITH PLENTY OF ONSHORE FLOW
CONTINUING...MAINTAINING A FAIR AMOUNT OF CLOUD COVER. THERE ARE SOME
BREAKS IN THE CLOUDS WITH A BIT OF SUNSHINE PEAKING THROUGH THAT MAY
ALLOW TEMPS TO REACH THE 65 TO 70 RANGE TODAY INLAND. CANNOT RULE OUT
A FEW SHOWERS DEVELOPING IN THE AFTERNOON FROM THE DAYTIME
HEATING...BUT RIGHT NOW THE MOST ARE IN THE NORTHWEST CORNER OF OUR
FORECAST AREA. WILL MONITOR ANY CHANCES OF SEEING THUNDER LATER TODAY
OR THIS EVENING BUT WILL CONTINUE TO LEAVE OUT FOR NOW.
THE NEXT DECENT SHORT WAVE DISTURBANCE HAS CROSSED INSIDE OF 130W
THIS AFTERNOON. THIS DISTURBANCE WILL SPREAD ONSHORE THIS EVENING AND
MOVE ACROSS OUR FORECAST AREA TONIGHT INTO EARLY SUNDAY. THIS FEATURE
WILL MORE SIGNIFICANTLY INCREASE THE SHOWERS OVER SOUTHWEST
WASHINGTON AND NORTHWEST OREGON OVERNIGHT TONIGHT WITH A DECENT SLUG
OF QPF. THIS FEATURE WILL MOVE EAST EARLY SUNDAY. HOWEVER...THE
COMMA CLOUD BAND AROUND THE LOW CENTER ITSELF THAT IS NOW BETWEEN
130W AND 135W IS FORECAST TO SWING ONSHORE INTO SOUTHWEST WASHINGTON
AND NORTHWEST OREGON DURING THE DAY SUNDAY AS THE LOW CENTER DRIFTS
INSIDE 130W AND CLOSER TO THE COAST. WE SHOULD SEE TEMPS ALOFT AT
500 MB FALL TO MINUS 22 TO MINUS 23 DEG C ON SUNDAY...AND THUS
EXPECT MORE SHOWERS FROM THIS FEATURE...WITH EVEN A SMALL CHANCE OF
THUNDER OVER OUR AREA SUNDAY AFTERNOON AND EVENING. THE CHANCE OF
ANY THUNDER WILL DEPEND ON HOW WARM IT GETS SUNDAY AND HOW SOLID THE
CLOUDS ARE. RIGHT NOW IT MAY BE PRETTY CLOUDY AND IT WILL PROBABLY
BE THE COOLEST DAY OF THIS STRETCH...BUT WILL STAY WITH A SLIGHT
CHANCE OF THUNDER.
THE LOW WILL STILL LINGER JUST OFF THE COAST THROUGH EARLY MONDAY
THEN DRIFT SOUTH TOWARD CALIFORNIA. THIS MAY ALLOW MORE SUN BREAKS TO
DEVELOP MONDAY AFTERNOON AND EVENING...WHILE STILL BEING UNDER THE
CYCLONIC CIRCULATION TO THE NORTH OF THE LOW. THIS COULD LEAD TO THE
BEST CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS FROM THIS
LOW.
THE LOW IS WELL SOUTH OF OUR AREA ON TUESDAY...WITH NORTHWEST
ONSHORE FLOW CONTINUING. THE THREAT OF SHOWERS SHOULD BE
WANING...THOUGH WE MIGHT SEE A FEW POP UP OVER THE HIGHER TERRAIN IN
THE AFTERNOON AND EVENING. TEMPS INLAND MAY PUSH UP INTO THE LOWER
70S AGAIN.
SNOW LEVELS WILL REMAIN ABOVE THE CASCADE PASSES DURING THE ENTIRE
SHORT TERM PERIOD...BUT THE HIGHER MOUNTAINS IN THE CASCADES WILL SEE
SOME SNOW ESPECIALLY THROUGH MONDAY. TOLLESON
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...THE CLOSED UPPER LEVEL
LOW MOVING THROUGH THE PAC NW THIS WEEKEND AND EARLY NEXT WEEK IS
EXPECTED TO PUSH SOUTH INTO CALIFORNIA ON TUE...AND WILL LIKELY BE IN
THE U.S. SOUTHWEST BY TUE NIGHT. MODEL AGREEMENT IS GOOD THAT AN
UPPER LEVEL RIDGE WILL THEN BUILD OVER THE PAC NW FROM TUE NIGHT INTO
THU. THIS SHOULD BRING A COUPLE OF DAYS OF WARMER AND DRIER WEATHER
ON WED AND THU. IT APPEARS THAT AN UPPER LEVEL TROF OVER THE GULF OF
ALASKA WILL TRY TO SWING A COUPLE OF SHORTWAVES TOWARD THE REGION FRI
AND SAT. THERE IS SOME UNCERTAINTY IN HOW MUCH IMPACT THERE WILL BE
FROM THESE WAVES. THE 12Z ECMWF RUN MOVES THE UPPER RIDGE OFF TO THE
EAST AND BRINGS ORGANIZED PRECIPITATION INTO THE REGION...WHILE THE
12Z GFS KEEPS THE RIDGE MORE OR LESS IN PLACE AND KEEPS THINGS MAINLY
DRY. FOR NOW...WILL CONTINUE TO KEEP LOW CHANCE POPS IN THE FCST FOR
FRI AND SAT. PYLE
&&
.AVIATION...GENERALLY VFR ACROSS THE REGION THIS AFTERNOON WITH A
BROKEN TO OVERCAST DECK AROUND 5000-6000 FT. THE EXCEPTION IS SW
WASHINGTON/N OREGON COAST WHERE FLOW IS MORE ONSHORE AND LOWER CLOUDS
HAVE DEVELOPED. EXPECT LOWERING CIGS AND RAIN TONIGHT AS FRONTAL
SYSTEM APPROACHES. MVFR CIGS LIKELY AFTER 05Z AT THE COAST...AND 08Z
ACROSS THE INTERIOR AS FRONT PROGRESSES. A MIX OF HIGH-END IFR AND
MVFR CONDITIONS POSSIBLE AT THE COAST OVERNIGHT SUN...WHILE MVFR/VFR
ACROSS THE INTERIOR THROUGH SUN WITH RAIN CONTINUING AND A SLIGHT
CHANCE OF THUNDERSTORMS SUN AFTERNOON.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH AT LEAST 06Z SUN. MVFR
CIGS LIKELY ARRIVE AROUND 08Z SUN AS FRONT ARRIVES. RAIN CONTINUES
THROUGH SUN BUT WITH SOME IMPROVEMENT TO HIGH END MVFR TO LOWER VFR
CONDITIONS LIKELY. SLIGHT CHANCE OF THUNDERSTORMS SUN AFTERNOON.
CULLEN
&&
.MARINE...WEAK HIGH PRES LOCATED NEAR THE COAST CONTINUES TO SHIFT E
TODAY. THE LOW PRES SYSTEM OFFSHORE OF VANCOUVER ISLAND WILL MOVE S
AND PASS THROUGH THE COASTAL WATERS TONIGHT AND SUN...AND BE LOCATED
OFFSHORE NEAR THE CALIFORNIA/OREGON BORDER BY LATE SUN NIGHT. A WEAK
FRONT ASSOCIATED WITH THE LOW WILL MOVE ACROSS THE COASTAL WATERS
TONIGHT. GUSTY S WINDS TO 20 KT POSSIBLE OFF THE CENTRAL OREGON COAST
SUN EVENING AS THE LOW PRES MOVES THROUGH...ALONG WITH A SLIGHT
POSSIBILITY OF THUNDERSTORMS OVER THE WATERS. HIGH PRES REBUILDS
OFFSHORE LATER MON...AND N WINDS WILL INCREASE BY MIDWEEK WITH GUSTY
25 KT WINDS POSSIBLE. SEAS WILL REMAIN 3 TO 6 FT THROUGH MOST OF NEXT
WEEK...BUT WIND DOMINATED AND CHOPPY AT TIMES. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
1039 AM PDT SAT MAY 17 2014
.SYNOPSIS...
High pressure will continue to break down through Saturday, while
low pressure migrates Inland for Sunday and early next week.
Disturbances rounding the low will bring shower and thunderstorm
chances to northern Washington and the Northern Panhandle of Idaho
through Saturday. The weather will remain unsettled through the
first part of next week, with showers and a threat of
thunderstorms, and cooler temperatures. The shower threat wanes
and temperatures moderate towards the middle of next week.
&&
.DISCUSSION...
Updates this morning have included some updating of the hydrologic
products in effect for the area this morning. Additionally some
cloud and pop grid updates have taken places as well. Forecast
temperatures seem reasonable but may make a tweak to them here and
there but nothing that would make too big of an impact. HRRR runs
over the past few hours continue to suggest convection up north
this afternoon sharing some similarity to yesterday but with a bit
more coverage. /Pelatti
&&
.AVIATION...
18z TAFS: Low pressure moving in from off the coast will continue
to influence the aviation area by streaming in not only middle
and high clouds but also advecting in some lower level moisture
and keeping the atmosphere somewhat unstable to allow for
convective showers and thunderstorms during late morning and into
the early evening. Regardless VFR conditions should prevail except
for perhaps brief MVFR ceilings and visibilities near and below
the more intense showers and thunderstorms. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 68 44 64 43 64 45 / 20 20 50 50 50 20
Coeur d`Alene 67 43 63 40 63 42 / 20 20 60 60 50 30
Pullman 66 43 62 41 63 41 / 10 20 60 50 40 20
Lewiston 74 48 68 45 69 47 / 10 20 50 40 30 20
Colville 70 42 68 41 69 43 / 50 40 60 60 50 30
Sandpoint 66 41 62 40 62 39 / 30 30 50 60 60 40
Kellogg 66 42 61 39 62 42 / 20 30 60 60 50 40
Moses Lake 76 46 72 46 73 46 / 10 10 20 20 30 10
Wenatchee 75 50 71 48 71 51 / 10 10 20 20 20 10
Omak 73 43 70 42 71 43 / 30 30 30 30 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
337 PM CDT SAT MAY 17 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 337 PM CDT SAT MAY 17 2014
LATEST WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS SHOWED AN UPPER
LEVEL TROUGH EXTENDING FROM NEAR HUDSON BAY SOUTH INTO THE EASTERN
GREAT LAKES. THE TROUGH WAS MAKING PROGRESS TO THE EAST AS RIDGING WAS
BUILDING INTO THE ROCKIES. THE POSITION OF THESE TWO FEATURES
PLACES THE UPPER MISSISSIPPI RIVER VALLEY IN NORTHWEST FLOW ALOFT
WITH WEAK EMBEDDED SHORTWAVES NOTED. THE COMBINATION OF THE
SHORTWAVES AND DEEP MIXING HAS ALLOWED FOR THE DEVELOPMENT OF
SCATTERED TO BROKEN CUMULUS THIS AFTERNOON WITH A FEW RETURNS
NOTED ON RADAR OVER PORTIONS OF SOUTH CENTRAL MINNESOTA WHERE
ENHANCE CUMULUS MAY PRODUCE A FEW LIGHT SPRINKLES. SOME OF THESE
LIGHT SPRINKLES MAY MAKE IT INTO PORTIONS OF SOUTHEAST MINNESOTA
AND NORTHEAST IOWA BUT THEY WILL QUICKLY DIE OFF LATE THIS
AFTERNOON WITH THE LOSS OF DAYTIME HEATING. WITH SLIGHTLY WARMER
AIR OVER THE REGION THIS EVENING AND A SLIGHTLY TIGHTER PRESSURE
GRADIENT WE SHOULDN/T HAVE FROST CONCERNS TONIGHT WITH
TEMPERATURES BOTTOMING OUT IN THE UPPER 30S OVER NORTH CENTRAL
WISCONSIN TO THE LOWER 40S ACROSS NORTHEAST IOWA. WILL HAVE TO
KEEP A CLOSE EYE ON EASTERN TAYLOR COUNTY WHERE TEMPERATURES COULD
FALL INTO THE MID 30S AND FROST WOULD BE POSSIBLE IN THESE AREAS.
ON SUNDAY...UPPER RIDGING WILL BUILD INTO THE REGION WITH PARTLY TO
MOSTLY SUNNY SKIES EXPECTED. THE PRESSURE GRADIENT WILL CONTINUE
TO TIGHTEN OVER THE UPPER MISSISSIPPI RIVER VALLEY ON SUNDAY AS
SURFACE HIGH PRESSURE SLIDES OVER THE OHIO RIVER VALLEY AND LOW
PRESSURE DEEPENS OVER THE HIGH PLAINS/BLACK HILLS AREA. PLAN ON
SOUTHWEST WINDS OF 10 TO 17 MPH WITH GUSTS APPROACHING 28 MPH
DURING THE AFTERNOON HOURS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 337 PM CDT SAT MAY 17 2014
THE UPPER RIDGE WILL FLATTEN AND SLIDE EAST ON MONDAY AS A
SHORTWAVE TROUGH LIFTS NORTHEAST ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY. THE BEST 925-850 MB MOISTURE TRANSPORT LOOKS TO PUSH
INTO THE REGION MONDAY AFTERNOON INTO MONDAY EVENING LEADING TO
SHOWERS AND THUNDERSTORMS. THE BULK OF THIS ACTIVITY SHOULD OCCUR
NORTH F THE INTERSTATE 90 CORRIDOR WITH AN ELEVATED MIXED
LAYER...CENTERED AROUND 700 MB...HELPING TO EFFECTIVELY CAP
CONVECTIVE ACTIVITY. THE BULK OF THE ENERGY FROM THIS SYSTEM
PASSES NORTH OF THE FORECAST AREA AS LOW PRESSURE DEEPENS OVER
SOUTHERN MANITOBA INTO SOUTHWEST ONTARIO. THE LOW THEN SLIDES OVER
FAR NORTHERN LAKE SUPERIOR/SOUTHERN ONTARIO ON TUESDAY AS A BOUNDARY
SAGS SOUTH ACROSS THE FORECAST AREA. WE DO BUILD SOME SURFACE
BASED CAPE ON TUESDAY AS TEMPERATURES CLIMB INTO THE MID TO
POSSIBLY UPPER 70S. FORECAST SOUNDINGS SUGGEST SURFACE BASED CAPE
VALUES COULD APPROACH 1300 J/KG. CANNOT RULE OUT SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOPING OVER NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN TUESDAY AFTERNOON INTO TUESDAY EVENING BUT THERE ISN/T
MUCH UPPER LEVEL SUPPORT...WITH WEAK SUBSIDENCE OVER THE REGION.
THERE IS A SUBTLE SHORTWAVE THAT MOVES OVER THESE AREAS LATE
TUESDAY AFTERNOON INTO TUESDAY EVENING SO THIS MAY PROVIDE JUST
ENOUGH SUPPORT TO SPARK A FEW SHOWERS AND STORMS. BEYOND
TUESDAY...HIGH PRESSURE APPEARS TO BE THE DOMINANT WEATHER
FEATURE THROUGH THE END OF THE WORK WEEK WITH MAINLY DRY AND QUIET
WEATHER EXPECTED. HIGH TEMPERATURES WILL BE VERY PLEASANT RANGING
FROM THE UPPER 60S TO LOWER 70S. THIS TREND COULD CONTINUE RIGHT
INTO THE MEMORIAL DAY WEEKEND. EXTENDED FORECAST MODELS SUGGEST
THERE COULD BE SOME LOW CHANCES FOR SHOWERS AND STORMS SATURDAY
INTO SUNDAY. LEANED TOWARD A MODEL CONSENSUS BLEND ON SATURDAY BUT
WE WILL HAVE TO SEE HOW THE RIDGE EVOLVES THE NEXT FEW MODEL RUNS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1232 PM CDT SAT MAY 17 2014
VFR CONDITIONS TO OCCUR THROUGH TOMORROW MORNING WITH A DRY AIR
MASS IN PLACE ACROSS THE REGION. WESTERLY WINDS HAVE BECOME GUSTY
AT RST TO AROUND 20KTS. WITH A CU DECK FORMING ACROSS THE
REGION...THERE ARE SOME INDICATIONS THAT A FEW SHOWERS MAY DEVELOP
OVER SOUTHWEST MINNESOTA AND TRACK EAST INTO THE REGION. EVEN IF A
SHOWER DOES HIT RST OR LSE...CONDITIONS SHOULD STAY VFR DUE TO HOW
HIGH BASED THE CLOUDS ARE AT 8-10KFT. WINDS WILL DIMINISH THIS
EVENING BEFORE PICKING BACK UP TOMORROW MORNING.
&&
.HYDROLOGY...
ISSUED AT 337 PM CDT SAT MAY 17 2014
WATER LEVELS ALONG THE MISSISSIPPI RIVER WILL CONTINUE TO RUN HIGH
THROUGH THE WEEKEND AND INTO NEXT WEEK. SOME MINOR FLOODING IS
ALREADY OCCURRING OR EXPECTED TO OCCUR INTO NEXT WEEK.
FOR MORE DETAILED INFORMATION...LOOK ON OUR INTERNET PAGE AT
WWW.WEATHER.GOV/LACROSSE. CLICK ON THE NEWS STORY AT THE TOP OF
THE PAGE PERTAINING TO THE MISSISSIPPI RIVER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...HALBACH
HYDROLOGY...WETENKAMP
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
318 PM CDT SAT MAY 17 2014
.SHORT TERM...
.TONIGHT AND SUNDAY...FORECAST CONFIDENCE HIGH.
THE BROAD MID LEVEL TROUGH OVER THE GREAT LAKES REGION WILL MAKE
VERY LITTLE PROGRESS TO THE EAST UNTIL SUNDAY AFTERNOON. WEAK
SHORTWAVES CONTINUE TO ROTATE THROUGH THIS UPPER TROUGH. WEAK LOW
LEVEL WARM AIR ADVECTION IS ALSO ONGOING OVER SOUTHERN MN. THE CLOUD
LAYER OVER THE REGION IS THIN PER RAP SOUNDINGS...INSTABILITY IS
WEAK...AND THE AIR BELOW 7000 FEET IS VERY DRY. SCATTERED SPRINKLES
ARE APPARENT ON RADAR OVER PORTIONS OF SOUTHEAST WI AND
CENTRAL/SOUTHERN MN. THE MN CLOUDS AND SPRINKLES WILL SWING THROUGH
SOUTHERN WI THIS EVENING.
EXPECT SKIES TO BECOME MOSTLY CLEAR LATE TONIGHT. WITH 925MB AND
850MB TEMPS GRADUALLY WARMING...OVERNIGHT LOWS WILL ONLY DIP INTO
THE LOWER 40S AND NO FROST IS EXPECTED ACROSS THE MKX FORECAST AREA.
WITH THE UPPER TROUGH STILL OVERHEAD...EXPECT CLOUDS TO DEVELOP
ACROSS SOUTHERN WI ONCE AGAIN BY LATE SUNDAY MORNING. THERE COULD
EVEN BE A FEW SPRINKLES AGAIN BUT NOTHING MORE. WINDS WILL BE A
LITTLE BREEZY OUT OF THE SOUTHWEST DUE TO THE DRY LOW LEVEL AIR AND
MIXING. TEMPERATURES WILL BE WARMER WITH HIGHS IN THE MID 60S.
CLOUDS WILL THIN OUT FROM WEST TO EAST DURING THE LATE AFTERNOON AS
MID LEVEL RIDGING STARTS TO MOVE IN.
.SUNDAY NIGHT AND MONDAY...FORECAST CONFIDENCE...HIGH.
THE MID/UPPER LEVEL RIDGE BUILDS ACROSS THE UPPER MISSISSIPPI
VALLEY SUNDAY NIGHT AND INTO WISCONSIN ON MONDAY. MODERATE UPPER
LEVEL DIVERGENCE OCCURS MONDAY...ALONG WITH DEVELOPING WEAK
UPWARD 700 MB MOTION. THE 700 MB LAYER IS DRY SUNDAY NIGHT...BUT
INCREASES EARLY MONDAY MORNING...WITH A BAND OF MOISTURE
CONVERGENCE AS THE 700 MB LAYER SATURATES AS IT MOVES ACROSS
SOUTH CENTRAL WISCONSIN...REACHING THE SOUTHEAST DURING THE
AFTERNOON. THE 850 MB LAYER STAYS RELATIVELY DRY SUNDAY NIGHT AND
MONDAY...INCREASING ONLY THE THE WEST LATE MONDAY AFTERNOON...EVEN
THOUGH THE 850 MB FLOW INCREASES TO 35 KNOTS MONDAY
AFTERNOON. THE MAIN 850 MB LOW LEVEL JET IS ACROSS MISSOURI TO
MINNESOTA. THERE IS NO ZERO TO 1 KM CAPE OVER SOUTHERN WISCONSIN.
THE SURFACE HIGH IS STILL CENTERED OVER THE EASTERN GREAT LAKES
WITH THE SOUTH LOW LEVEL FLOW AND 850/700 MB WARM AIR ADVECTION
CONTINUING. SOME LIGHT PRECIPITATION AFFECTS SOUTH CENTRAL AND
SOUTHEAST WISCONSIN ON THE 00Z ECMWF AND 12Z GFS...BUT THE 12Z NAM
IS DRY...EXCEPT WEST OF MADISON DURING THE AFTERNOON. EXPECT A
SOUTHEAST FLOW OFF LAKE MICHIGAN...SO AREAS NEAR LAKE MICHIGAN
WILL BE RATHER COOL.
.MONDAY NIGHT AND TUESDAY...FORECAST CONFIDENCE...HIGH.
THE UPPER RIDGE MOVES OFF TO THE EAST WITH A MAINLY WEST/SOUTHWEST
UPPER FLOW. WISCONSIN WILL BE IN THE EXIT REGION OF THE
APPROACHING UPPER JET ON TUESDAY...WITH SOME WEAK TO MODERATE
UPPER DIVERGENCE.
WEAK TO MODERATE 700 MB UPWARD MOTION MONDAY NIGHT AND AGAIN
TUESDAY AROUND NOON. 700 MB RH IS SATURATED MAINLY ACROSS THE
NORTH AREAS MONDAY NIGHT. THE SOUTH 35 TO 40 KNOT 850 MB LOW
LEVEL JET MOVES ACROSS THE AREA MONDAY NIGHT...WITH WEAK SOUTHWEST
FLOW TUESDAY. 700 MB TEMPERATURES RISE TO 8 TO 10 CELSIUS MONDAY
NIGHT BUT COOL ON TUESDAY AS THE THERMAL RIDGE SAGS SOUTH ACROSS
ILLINOIS.
THE NAM DOES GENERATE 650 TO 1100 JOULES/KG OF CAPE TUESDAY
AFTERNOON.
THE APPROACHING WEAK LOW PRESSURE TROUGH MOVES PUSHES INTO THE
MID/UPPER MISSISSIPPI VALLEY TUESDAY....WITH A WARM FRONT ACROSS
THE WISCONSIN ILLINOIS BORDER REGION. AGAIN EXPECT A SOUTHEAST
FLOW OFF LAKE MICHIGAN...SO AREAS NEAR LAKE MICHIGAN WILL BE
RATHER COOL.
.LONG TERM...
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE HIGH.
THE UPPER RIDGE EXITS TO THE EAST OF THE EASTERN GREAT LAKES AS A
SHORTWAVE MOVES ACROSS THE U.S./CANADA BORDER REGION IN THE ZONAL
FLOW OVER THE NORTHERN TIER OF THE U.S.
WEAK LOW PRESSURE MOVES ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT
WITH A RIDGE BUILDING INTO THE UPPER MISSISSIPPI VALLEY
WEDNESDAY...PUSHING THE SURFACE BOUNDARY SOUTH INTO THE UPPER OHIO VALLEY.
.THURSDAY AND FRIDAY....FORECAST CONFIDENCE HIGH.
THE MID/UPPER LEVEL FLOW BECOMES MORE WEST NORTHWEST BEFORE A
RIDGE MOVES INTO WISCONSIN LATER FRIDAY.
WEAK HIGH PRESSURE BUILDS INTO THE UPPER GREAT LAKES AND
WISCONSIN THURSDAY AND FRIDAY.
.SATURDAY...FORECAST CONFIDENCE MEDIUM.
THE MID/UPPER LEVEL RIDGE REMAINS OVER WISCONSIN SATURDAY AS A
WEAK SHORTWAVE PUSHES INTO IT FROM THE NORTHERN PLAINS AND
WEAKENS.
THE SURFACE HIGH REMAINS OVER THE GREAT LAKES...WITH JUST A
HUNDRETH OR SO OF PRECIPITATION ON THE 00Z ECMWF. THE 12Z GFS AND
06Z DGEX REMAIN DRY WHICH IS PREFERRED.
&&
.AVIATION/00Z TAFS/...
VFR THROUGH THE PERIOD. A BROAD UPPER LEVEL LOW PRESSURE SITTING
OVER THE GREAT LAKES REGION WILL KEEP CLOUDS OVERHEAD THROUGH THIS
EVENING AND AGAIN FROM LATE SUNDAY MORNING THROUGH THE AFTERNOON.
SOME SPRINKLES ARE POSSIBLE.
LOW LEVEL WIND SHEAR IS LIKELY OVERNIGHT WITH SOUTHWEST WINDS UP TO
35 KNOTS BETWEEN 1000 AND 3000 FEET AGL.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...MRC
SUNDAY NIGHT THROUGH SATURDAY...HENTZ