Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/25/13

AREA FORECAST DISCUSSION

NWS EUREKA CA

950 AM PDT TUE APR 23 2013

.UPDATE...HAVE ADJUSTED MAX TEMPS UP QUITE A BIT AT COASTAL
LOCATIONS. TEMPS AT THE COAST HAVE ALREADY REACHED YESTERDAY`S MAX
VALUES AND JUST INLAND FROM THE COAST ARE SEVERAL DEGREES ABOVE
YESTERDAY`S VALUES. LIGHT OFFSHORE FLOW IS DOWNSLOPING...CAUSING
RH VALUES ALONG THE COAST TO CRASH AS WELL. BOTH RUC AND GFS
INDICATE 1000-700MB THICKNESSES RISING A BIT MORE TODAY BEFORE
COMING DOWN TONIGHT AND WED. EXPECT MAX TEMPS TO REACH AT LEAST
THE MID 70S AT KACV BEFORE ONSHORE FLOW KICKS IN THIS AFTERNOON.
WILL CONTINUE TO MONITOR FOR ADDITIONAL UPDATES. /SEC

.PREV DISCUSSION... /ISSUED 438 AM PDT TUE APR 23 2013/

SYNOPSIS...HIGH PRESSURE AND OFFSHORE FLOW IS BRINGING MOSTLY
CLEAR SKIES AND WARM TEMPERATURES TO THE AREA TODAY. HIGH
PRESSURE WILL PERSIST THROUGH THE WEEK BUT COASTAL STRATUS WILL
MOVE UP THE COAST FROM THE SOUTH REACHING THE MENDOCINO COAST BY
LATE THIS AFTERNOON AND TO THE REDWOOD COAST BY WEDNESDAY. A WEAK
SYSTEM WILL BRING SOME CLOUDS AND COOLER TEMPERATURES LATE IN THE
WEEK.

SHORT TERM...HIGH PRESSURE AND STRONG OFFSHORE FLOW IS KEEPING
THE AREA CLEAR THIS MORNING. AREAS ALONG THE COAST WITH WIND HAVE
BEEN WARMING OVERNIGHT WITH LOW 60S REPORTED IN SOME AREAS WHILE
NEARLY CALM LOCATIONS CONTINUE TO SHOW MID 40S. CURRENTLY NEAREST
CLOUDS ARE DOWN BY BODEGA BAY AND MOVING NORTH UP THE COAST.
EXPECT THEY WILL MOVE INTO POINT ARENA LATE THIS
AFTERNOON...ALTHOUGH IT COULD BE A BIT EARLIER. LOCAL WRF BACKS
THIS UP SHOWING SOME SOUTHERLY WINDS SPREADING NORTH THIS
AFTERNOON AS WELL. NORTHERLIES ARE STILL FAIRLY STRONG SO EXPECT
IT WILL TAKE A BIT FOR THE STRATUS TO MAKE IT AROUND CAPE
MENDOCINO. TEMPERATURES TODAY SHOULD BE FAIRLY SIMILAR TO
YESTERDAY...EXCEPT IN AREAS OF MENDOCINO COUNTY WHERE THE MARINE
LAYER WILL KEEP THINGS A BIT COOLER. KEPT SKIES CLEAR NORTH OF
CAPE MENDOCINO TONIGHT WITH STRONG OFFSHORE FLOW REMAINING IN
PLACE.

WEDNESDAY IT LOOKS LIKE THE STRATUS WILL MAKE IT AROUND CAPE
MENDOCINO IN THE MORNING AND PUSH INLAND TO THE REDWOOD COAST
BY AFTERNOON. NAM IS STILL STRUGGLING WITH THIS...LOOKS TO BE
ABOUT 24 HOURS TOO SLOW IN BRINGING THEM IN. INITIALIZATION WAS
QUITE POOR...IT WAS NOT EVEN SHOWING THE CLOUDS DOWN BY THE SFO
BAY AREA. THE RIDGE BEGINS TO WEAKEN ON WEDNESDAY SO THIS SHOULD
KEEP TEMPERATURES INLAND A FEW DEGREES COOLER AS WELL. IF THE
MARINE LAYER DOES MAKE IT AROUND THE CAPE ON WEDNESDAY
TEMPERATURES NEAR THE COAST WILL BE MUCH COOLER THAN ON TUESDAY.

WEDNESDAY NIGHT INTO THURSDAY MORNING EXPECT WIDESPREAD CLOUDS
AND SOME FOG ALONG THE COASTAL AREAS. THESE SHOULD PUSH BACK TO
THE COAST AND THERE MAY BE SOME PARTIAL CLEARING AT THE COAST
THURSDAY AFTERNOON. TEMPERATURES INLAND WILL COOL A FEW DEGREES ON
THURSDAY AS THE RIDGE CONTINUES TO WEAKEN AND TEMPERATURES ALOFT
DROP A DEGREE OR TWO. MKK

LONG TERM...MODEL SOLUTIONS BEGINS TO DIVERGE ON FRIDAY. THE 06Z
GFS RUN HAS A WEAKER SYSTEM MOVING THROUGH MORE QUICKLY ON
SATURDAY WITH A RIDGE BUILDING BACK IN BEHIND IT ON SUNDAY AND
MONDAY. THE 00Z ECMWF KEEPS THE RIDGE IN PLACE THROUGH EARLY
SUNDAY BEFORE BRINGING A DEEPER TROUGH THROUGH ON MONDAY AND
TUESDAY. THIS ECMWF SOLUTION IS A LOT SLOWER ON MOVING THE TROUGH
THROUGH THAN PREVIOUS RUNS. EITHER SOLUTION BRING LITTLE TO NO
RAINFALL TO THE AREA THROUGH THE NEXT WEEK. SO CONFIDENCE IS
LOWER THAN AVERAGE THROUGH THE EXTENDED. MKK

AVIATION...FOG SATELLITE SHOWS CLEAR SKIES ACROSS NORTHWEST
CALIFORNIA, MAINLY DUE TO OFFSHORE FLOW. EXPECT VFR TO PREVAIL.
GUSTY NORTHERLY WINDS WILL DEVELOP ALONG THE COAST THIS AFTERNOON AS
HIGH PRESSURE OFFSHORE INTERACTS WITH A THERMAL TROUGH INLAND. WINDS
SHOULD BE LESS BREEZY INLAND.

MARINE...NO MAJOR CHANGES MADE TO THE MARINE FORECAST. NORTHERLY
WINDS WILL CONTINUE AS HIGH PRESSURE OFFSHORE INTERACTS WITH A
THERMAL TROUGH INLAND TO MAINTAIN A STRONG PRESSURE GRADIENT.
NEARSHORE BUOYS SHOW LIGHT TO MODERATE WINDS WHILE THE 04Z ASCAT
PASS SHOWED WINDS OF ABOUT 25-30 KT ACROSS ZONE 470 (WHICH MATCHES A
SHIP REPORT THERE OF ABOUT 30 KT) AND 20-25 KT ACROSS ZONE 475. WAVE
OBSERVATIONS SEEM TO MATCH THE LATEST SWAN RUN. LEFT ALL OF THE
HEADLINES UNCHANGED. WINDS/SEAS WILL MAINTAIN THIS MORNING AND THEN
INCREASE/BUILD THIS AFTERNOON AS THE GRADIENT STRENGTHENS. GALE
CONDITIONS WILL CONTINUE FOR ZONE 470 THIS AFTERNOON THROUGH TONIGHT
WHERE GUSTS TO 40 KT ARE EXPECTED. VERY STEEP 12 TO 15 FT FRESH
SWELL GENERATED HERE WILL PROPAGATE INTO ZONE 475 WHERE THE
HAZARDOUS SEAS WARNING IS UP. GUSTS TO GALE FORCE ARE EXPECTED
ACROSS THE NORTHWEST PORTION OF THIS ZONE. EXPECT ELEVATED WINDS AND
SEAS ACROSS ZONE 450 THROUGH TONIGHT. MODELS ARE IN GOOD AGREEMENT
SHOWING THE GRADIENT WEAKENING LATE TONIGHT INTO WEDNESDAY WITH THE
WAVES SUBSIDING AT THE SAME TIME. THERE MAY BE SOME STRONGER WINDS
ACROSS THE EXTREME NORTHWEST PORTION OF ZONE 470 WHERE THE GRADIENT
MIGHT REMAIN STRONGER FOR A LITTLE BIT LONGER, THROUGH POSSIBLY
THURSDAY. REGARDLESS, EXPECT LIGHT TO MODERATE WINDS AND LOW SEAS
THURSDAY AND FRIDAY.

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 3 AM PDT WEDNESDAY PZZ450.

GALE WARNING UNTIL 3 AM PDT WEDNESDAY PZZ470.

SMALL CRAFT ADVISORY UNTIL 8 PM PDT WEDNESDAY PZZ475.

HAZARDOUS SEAS WARNING UNTIL 3 AM PDT WEDNESDAY PZZ475.

VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA

FOLLOW US ON FACEBOOK AND TWITTER AT:
HTTP://WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.EUREKA.GOV
HTTP://WWW.TWITTER.COM/NWSEUREKA

AREA FORECAST DISCUSSION

NWS TAUNTON MA

421 PM EDT TUE APR 23 2013

.SYNOPSIS...
A COASTAL STORM TRACKING SOUTHEAST OF NANTUCKET WILL BRING A
CHILLY RAIN TO SOUTHEAST NEW ENGLAND THROUGH TONIGHT. DRIER AND
MILD WEATHER ARRIVES WED. A QUICK MOVING COLD FRONT WILL PASS
THROUGH WEDNESDAY NIGHT INTO THURSDAY. MAINLY DRY AND SEASONABLY
COOL WEATHER RETURNS FRIDAY INTO EARLY NEXT WEEK THANKS TO STRONG
HIGH PRESSURE ANCHORED ACROSS THE REGION.

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
3 PM UPDATE...

WESTERN EDGE OF RAIN SHIELD OVER CAPE COD AND ISLANDS HAVING HARD
TIME MAKING PROGRESS INLAND. HIGHER RESOLUTION RAP HAS A VERY GOOD
HANDLE ON RADAR TRENDS AND ONLY BRINGS MEASURABLE RAINFALL INTO RI
AND EASTERN MA THROUGH THIS EVENING...BUT ONLY A FEW HUNDREDTHS AT
THAT. HEAVIEST RAINFALL WILL CONTINUE TO BE FOCUSED ON CAPE COD
AND ISLANDS. STILL HAVE POTENTIAL FOR ISOLATED THUNDER NEAR S
COAST AS UPPER TROUGH SWINGS THROUGH FROM MIDNIGHT TO DAYBREAK WED
AND AIRMASS DESTABILIZES ALOFT.

OTHERWISE CLOUDY SKIES EXPECTED THROUGHOUT REGION WITH SPOTTY
DRIZZLE AS FAR INLAND AS WORCESTER HILLS AND NW RI. USED A BLEND
OF GFS/NAM MOS FOR LOWS WHICH RANGE FROM MID 30S FAR NW TO MID 40S
SE.

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
SYSTEM WILL HEAD TO MARITIMES WED. MODELS DIFFER ON TIMING OF
ARRIVAL OF DRIER AIR WITH NAM A BIT SLOWER THAN OTHER MODELS...BUT
ALL SHOW ENOUGH DRYING BY MIDDAY TO ALLOW FOR AT LEAST PARTIAL
CLEARING...EVEN ALONG COAST. WE INDICATED CLEARING NEAR CT RIVER
VALLEY FIRST THING IN MORNING...AND BY MID TO LATE MORNING FARTHER
E. IT MAY TAKE UNTIL MIDDAY AROUND CAPE COD AND ISLANDS.

SOME QUESTION AS TO WHETHER OR NOT SEA BREEZES WILL DEVELOP WED.
IT DOES APPEAR GRADIENT WEAKENS ENOUGH IN AFTERNOON TO SUPPORT
THEIR DEVELOPMENT...BUT IT MAY TAKE UNTIL MID AFTERNOON FOR THAT
TO OCCUR. ANY SEA BREEZES SHOULD BE SHORT LIVED AS INCREASING SW
FLOW TAKES OVER TOWARD EVENING.

FORECAST HIGHS ARE A CHALLENGE AS NAM KEEPS MORE
CLOUDINESS/ONSHORE FLOW THAN GFS AND THEREFORE HAS COOLER
TEMPERATURES NEAR COAST. FAVORED WARMER GFS MOS WHICH YIELDS HIGHS
IN 60S COAST/70S INLAND.

NEXT FRONT IS ALREADY ON OUR DOORSTEP WED EVENING AND IS EXPECTED
TO CROSS SOUTHERN NEW ENGLAND OVERNIGHT. ALTHOUGH INSTABILITY IS
LIMITED...FAIRLY IMPRESSIVE JET DYNAMICS COULD COMPENSATE ENOUGH
TO PRODUCE ISOLATED THUNDER AS FRONT MOVES THROUGH. LIMITING
FACTOR IS DIMINISHING LOW LEVEL CONVERGENCE ALONG FRONT AS IT
REACHES NEW ENGLAND...SO ONLY INCLUDED CHANCE POPS AND MENTION OF
ISOLATED THUNDER FOR NOW.

SW FLOW SHOULD PREVENT TEMPERATURES FROM DROPPING MUCH WED NIGHT.
USED BLEND OF GFS/NAM MOS WHICH YIELDS LOWS IN 40S TO AROUND 50.

.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGHLIGHTS...

* COLD FRONT MOVES OFFSHORE THURSDAY
* WEAK WAVE PASSES N OF THE REGION FRIDAY
* STRONG HIGH PRESSURE TAKES OVER INTO EARLY NEXT WEEK

OVERVIEW AND MODEL PREFERENCES...
APPEARS THAT THE MEDIUM RANGE MODELS IN RATHER GOOD AGREEMENT AT
THE SURFACE AND ALOFT THROUGH MOST OF THIS PERIOD WITH ONLY MINOR
TIMING DIFFERENCES ACROSS THE EASTERN U.S...WHILE RATHER LARGE
DIFFERENCES WORK IN ACROSS THE WEST AND EASTERN PACIFIC MAINLY
INTO NEXT WEEKEND AND BEYOND. ACROSS THE LOWER 48...IT APPEARS
THAT ONCE THE H5 TROUGH TRAVERSES OUT OF THE GREAT LAKES INTO
NORTHERN NEW ENGLAND AND QUEBEC THU-FRI...THE OVERALL UPPER FLOW
TENDS TO FLATTEN OUT FROM THE PLAINS TO EASTERN SEABOARD. IT DOES
REMAIN SPLIT...WITH A WEAK SHORT WAVE MOVING ACROSS THE SOUTHERN
STREAM FRI-SUN.

OVER THE NORTHERN TIER STATES...THE UPPER PATTERN REMAINS FLAT WHILE
AT THE SURFACE...HIGH PRES WILL TAKE OVER ACROSS MOST OF THE EASTERN
U.S. BEGINNING LATE FRI-SAT THROUGH THE REMAINDER OF THE LONG TERM
PERIOD AND BEYOND. WHILE DRY AND SEASONABLE WEATHER IS EXPECTED...
MAY SEE TEMPS BEGIN TO RISE A BIT LATE IN THE PERIOD THOUGH TIMING
IS UNCERTAIN.

WITH MODEL SUITE AND ASSOCIATED ENSEMBLES IN RATHER GOOD AGREEMENT
ACROSS THIS REGION...LEANED THIS FORECAST TOWARD A BLEND OF THE 12Z
GFS/UKMET AND 00Z ECMWF WITH THE ECENS.

DETAILS...

THURSDAY...COLD FRONT WILL WORK OFFSHORE DURING THE MORNING WITH SCT
SHOWERS LINGERING ACROSS SE MA/S COASTAL RI. EXPECT THESE TO PUSH
OFFSHORE THOUGH CLOUDS MAY LINGER INTO THE AFTERNOON. HIGH PRES WILL
THEN BUILD INTO NORTHERN NEW ENGLAND DURING THE AFTERNOON...SO
EXPECT W-NW WINDS TO BRING DRIER AIR TO THE REGION.

ANOTHER SHORT WAVE WORKS E IN THE FAST UPPER FLOW OUT OF THE GREAT
LAKES. MAY SEE SOME CLOUDS WORK INTO S NH/N MA DURING THU NIGHT.

FRIDAY...AS THE SHORT WAVE WORKS ACROSS NORTHERN NEW ENGLAND...MOST
OF THE ENERGY AND MOISTURE WILL REMAIN WELL N OF THE REGION. MAY GET
CLIPPED WITH A LITTLE BIT OF THE SOUTHERN EXTENT OF THE PRECIP AREA.
HOWEVER...DRY AIR IN PLACE ALOFT WITH FAST W FLOW...SO NOT A LOT OF
PRECIP EXPECTED. HAVE SLIGHT CHANCE POPS MENTIONED DURING THE DAY
ACROSS S NH AND EXTREME N MA MAINLY N OF ROUTE 2. EXPECT HIGH PRES
TO BUILD ACROSS QUEBEC AND THE NORTHEAST BY FRI NIGHT.

SATURDAY-TUESDAY...LARGE HIGH PRES ANCHORS FROM NEWFOUNDLAND DOWN TO
THE MID ATLC COAST BY SAT...WHICH WILL KEEP DRY AND SEASONABLE
CONDITIONS IN PLACE FOR MOST OF THIS PERIOD. HIGH MAY START TO MOVE
OFFSHORE MON...WHICH MAY BRING MILDER TEMPS TOWARD THE END OF THE
PERIOD THOUGH TIMING IS STILL UNCERTAIN. HAVE KEPT SEASONABLY COOL
TEMPS GOING FOR NOW.

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...
MODERATE CONFIDENCE. NOT MUCH CHANGE IN CONDITIONS THROUGH EARLY
TONIGHT WITH MVFR CIGS ACROSS WESTERN NEW ENGLAND AND IFR CLOSER
TO COAST. STEADIER RAIN NOT EXPECTED TO GET MUCH FARTHER INLAND
THAN BOS-PVD LINE...THOUGH PATCHY DRIZZLE POSSIBLE AS FAR AS ORH.
E/NE WINDS GUST TO 25KT MAINLY NEAR COAST.

CONDITIONS SHOULD LOWER TO IFR/LIFR OVERNIGHT...AGAIN ESPECIALLY NEAR
COAST. POSSIBILITY OF ISOLD THUNDER AROUND CAPE COD AND ISLANDS
FROM MIDNIGHT UNTIL 8 AM WED.

EXPECT RAPID IMPROVEMENT TO VFR WED MORNING...POSSIBLY NOT UNTIL
MIDDAY ALONG IMMEDIATE COAST. SHOULD HAVE SEA BREEZES DEVELOP
EARLY TO MID AFTERNOON...A LITTLE LATER THAN USUAL.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. COULD SEE LOWER
CIGS/VSBYS THAN FCST THIS EVENING.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY...MODERATE CONFIDENCE EARLY...THEN HIGH CONFIDENCE. EXPECT
VFR ACROSS CENTRAL AND WESTERN AREAS. FOR S COASTAL RI/SE MA...
AREAS OF MVFR-IFR CIGS/VSBYS THROUGH MID MORNING...THEN SHOULD
IMPROVE TO VFR BY MIDDAY EXCEPT FOR SE MA...CAPE COD AND THE
ISLANDS WHERE LOCAL MVFR MAY LINGER INTO THE AFTERNOON. THU
NIGHT...VFR.

FRIDAY-SUNDAY...HIGH CONFIDENCE. VFR THROUGH PERIOD. MAY SEE BRIEF
LOCAL MVFR IN ANY WIDELY SCT SHOWERS FRIDAY ACROSS S NH/N MA
MAINLY N OF ROUTE 2.

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...HIGH CONFIDENCE THROUGH WEDNESDAY NIGHT.

SCA REMAINS POSTED THROUGH MOST OF TONIGHT DUE TO 25KT WINDS AND
ROUGH SEAS...AND EXTENDED THEM INTO WED NIGHT FOR OUTER WATERS
WHERE SEAS WILL TAKE LONGER TO SUBSIDE.

RAIN/DRIZZLE CONTINUES THROUGH TONIGHT AS LOW PRESSURE HEADS SE OF
NANTUCKET. MOST OF RAIN AND LOWER VSBYS WILL BE FOCUSED AROUND
CAPE COD AND ISLANDS...WHERE ISOLATED THUNDER IS ALSO POSSIBLE
BETWEEN MIDNIGHT AND DAYBREAK WED.

WINDS AND SEAS DIMINISH WED. GRADIENT SHOULD BE WEAK ENOUGH FOR
LOCAL SEA BREEZES TO DEVELOP WED AFTERNOON...BEFORE SW FLOW
INCREASES AHEAD OF NEXT COLD FRONT LATER IN DAY. WINDS MAY REACH
25KT WED NIGHT BUT WITH MILDER AIR FLOWING OVER COOLER WATERS
CONFIDENCE IS LOW. EXPECT SCATTERED SHOWERS/ISOLATED THUNDER WITH
PASSAGE OF COLD FRONT WED NIGHT.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY...MODERATE CONFIDENCE. SMALL CRAFT WILL BE NEEDED. FRONT
MOVES OFFSHORE WITH WIND SHIFT TO W. MAY SEE GUSTS UP TO 25 KT
EARLY...THEN WILL DIMINISH. SCT SHOWERS/ISOLATED THUNDER MAINLY ON
THE OUTER WATERS. SEAS AOA 5 FT...SUBSIDING ON THE NEAR SHORE
WATERS THU NIGHT.

FRIDAY THROUGH SUNDAY...HIGH CONFIDENCE FRI-SAT...MODERATE
CONFIDENCE SUNDAY. HIGH PRES BUILDS IN WITH DRY WEATHER AND GOOD
VSBY. LEFTOVER 5 FT SEAS DURING FRI ON THE OUTER WATERS SHOULD
SUBSIDE FRI NIGHT.

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR ANZ230-
232>234-236.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ231-235-
237-250-251-254>256.

$$
SYNOPSIS...EVT/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...EVT
AVIATION...EVT/JWD
MARINE...EVT/JWD

AREA FORECAST DISCUSSION

NWS TAUNTON MA

301 PM EDT TUE APR 23 2013

.SYNOPSIS...
A COASTAL STORM TRACKING SOUTHEAST OF NANTUCKET WILL BRING A
CHILLY RAIN TO SOUTHEAST NEW ENGLAND THROUGH TONIGHT. DRIER AND
MILD WEATHER ARRIVES WED. A QUICK MOVING COLD FRONT WILL PASS
THROUGH WED NIGHT INTO THURSDAY. MAINLY DRY AND SEASONABLY COOL
WEATHER RETURNS FRIDAY AND INTO THE WEEKEND THANKS TO A STRONG
HIGH PRESSURE SYSTEM.

.NEAR TERM /THROUGH TONIGHT/...
3 PM UPDATE...

WESTERN EDGE OF RAIN SHIELD OVER CAPE COD AND ISLANDS HAVING HARD
TIME MAKING PROGRESS INLAND. HIGHER RESOLUTION RAP HAS A VERY GOOD
HANDLE ON RADAR TRENDS AND ONLY BRINGS MEASURABLE RAINFALL INTO RI
AND EASTERN MA THROUGH THIS EVENING...BUT ONLY A FEW HUNDRETHS AT
THAT. HEAVIEST RAINFALL WILL CONTINUE TO BE FOCUSED ON CAPE COD
AND ISLANDS. STILL HAVE POTENTIAL FOR ISOLATED THUNDER NEAR S
COAST AS UPPER TROUGH SWINGS THROUGH FROM MIDNIGHT TO DAYBREAK WED
AND AIRMASS DESTABILIZES ALOFT.

OTHERWISE CLOUDY SKIES EXPECTED THROUGHOUT REGION WITH SPOTTY
DRIZZLE AS FAR INLAND AS WORCESTER HILLS AND NW RI. USED A BLEND
OF GFS/NAM MOS FOR LOWS WHICH RANGE FROM MID 30S FAR NW TO MID 40S
SE.

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
SYSTEM WILL HEAD TO MARITIMES WED. MODELS DIFFER ON TIMING OF
ARRIVAL OF DRIER AIR WITH NAM A BIT SLOWER THAN OTHER MODELS...BUT
ALL SHOW ENOUGH DRYING BY MIDDAY TO ALLOW FOR AT LEAST PARTIAL
CLEARING...EVEN ALONG COAST. WE INDICATED CLEARING NEAR CT RIVER
VALLEY FIRST THING IN MORNING...AND BY MID TO LATE MORNING FARTHER
E. IT MAY TAKE UNTIL MIDDAY AROUND CAPE COD AND ISLANDS.

FORECAST HIGHS ARE A CHALLENGE AS NAM KEEPS MORE
CLOUDINESS/ONSHORE FLOW THAN GFS AND THEREFORE HAS COOLER
TEMPERATURES NEAR COAST. FAVORED WARMER GFS MOS WHICH YIELDS HIGHS
IN 60S COAST/70S INLAND.

SW FLOW SHOULD PREVENT TEMPERATURES FROM DROPPING MUCH WED NIGHT.
USED BLEND OF GFS/NAM MOS WHICH YIELDS LOWS IN 40S TO AROUND 50.

.LONG TERM /THURSDAY THROUGH MONDAY/...
HIGHLIGHTS...

* COLD FRONT WILL PUSH THROUGH WED NIGHT INTO THURS
* WEAK WAVE ON FRIDAY
* STRONG HIGH PRESSURE FOR THE WEEKEND

CONFIDENCE LEVEL/MODEL GUIDANCE...
HIGH CONFIDENCE IN FORECAST THROUGH THE WEEKEND. 00Z MODEL
GUIDANCE IS IN FAIRLY GOOD AGREEMENT ON PRECIPITATION TIMING AND
FRONTAL PASSAGES. HIGH CONFIDENCE THAT A COLD FRONT WILL PUSH
ACROSS SNE BY WED NIGHT INTO THURSDAY...MODERATE CONFIDENCE ON
PRECIPITATION AMOUNTS. UPPER LEVEL LOW ON FRIDAY WILL PUSH A WEAK
WAVE OVER THE NORTH HALF OF THE REGION. HIGH CONFIDENCE ON
BUILDING HIGH PRESSURE FROM FRIDAY EVENING INTO EARLY MONDAY
MORNING THANKS TO SURFACE HEIGHTS APPROX 2-3 STANDARD DEVIATIONS
IN BOTH THE GFS AND EC ENSEMBLES.

DETAILS...

WED NIGHT INTO FRIDAY...
STRONG UPPER LEVEL TROUGH WILL BRING TWO WAVES OF ENERGY THROUGH
SNE. THE FIRST WILL OCCUR WED NIGHT INTO THURS DEVELOPING A
SURFACE LOW NORTH OF VT/NH AND PUSHING IT NORTHEASTWARD. THIS WILL
DRAG A COLD FRONT ACROSS SNE WED NIGHT. THIS FRONT HOWEVER REALLY
LOSES ITS MOISTURE AS IT MOVES THROUGH THE INTERIOR. BELIEVE THE
BEST AREA TO SEE ACCUMULATING AMOUNTS WILL BE OUT WEST...WITH SCT
SHOWERS ACROSS THE CENTRAL PART OF THE CWA. AS WE GET CLOSER TO
THE EAST COAST...DEWPOINTS ARE A TAD HIGHER AND WITH SOUTHWESTERN
FLOW...MORE MOISTURE IS ADVECTING INTO THE MID-LEVELS...SO EXPECT
PRECIP TO BE MORE ABUNDANT ACROSS THE EAST COAST BY EARLY THURS
MORNING. EXPECTING LESS THAN A 0.25 INCHES OF PRECIP AS THIS FRONT
WILL BE MOVING QUITE QUICKLY. THERE IS A CHANCE FOR SOME ISOLATED
THUNDER WITH THIS SYSTEM...YET THE POSSIBILITY OF STRONG STORMS IS
QUITE LOW.

THE SECOND WAVE THAT ROUNDS THE TROUGH WILL MOVE THROUGH SNE BY
THURS NIGHT INTO FRIDAY MORNING. THIS SYSTEM AM LESS CONFIDENCE
ABOUT AS THERE IS PLENTY OF DRY AIR ALOFT AND HIGH PRESSURE IS
QUICKLY BUILDING BEHIND IT...PUSHING IT MORE NORTHWARD TOWARDS
NORTHERN NEW ENGLAND. BELIEVE THAT PERHAPS SCT SHOWERS ARE
POSSIBLE...BUT MORE LIKE SPRINKLES IN AREAS NORTH OF THE MASS PIKE.

THE WEEKEND...
AS THE TROUGH MOVES OFFSHORE...HIGH PRESSURE WILL BUILD IN FOR
THE WEEKEND. ZONAL FLOW ALOFT WILL TRY TO PUSH A FEW WAVES THROUGH
SNE...BUT BELIEVE THE AREA WILL BE TO DRY SO PERHAPS JUST PASSING
CLOUDS. THIS HIGH PRESSURE SEEMS TO BUILD OVER SNE FOR SOME TIME
AND MODELS ARE HAVING A HARD TIME ON WHEN TO PUSH IT OUT OF THE
REGION FOR EARLY NEXT WEEK. REGARDLESS...EXPECT MOST CLEAR SKIES
AND TEMPS IN THE MID TO UPPER 60S.

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

CONDITIONS SHOULD LOWER TO IFR/LIFR OVERNIGHT...AGAIN ESPECIALLY NEAR
COAST. POSSIBILITY OF ISOLD THUNDER AROUND CAPE COD AND ISLANDS
FROM MIDNIGHT UNTIL 8 AM WED.

EXPECT RAPID IMPROVEMENT TO VFR WED MORNING...POSSIBLY NOT UNTIL
MIDDAY ALONG IMMEDIATE COAST. SHOULD HAVE SEA BREEZES DEVELOP
EARLY TO MID AFTERNOON...A LITTLE LATER THAN USUAL.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. COULD SEE LOWER
CIGS/VSBYS THAN FCST THIS EVENING.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY...MODERATE CONFIDENCE. VFR FOR THE MAJORITY...QUICK
MOVING COLD FRONT MAY LEAD TO MVFR/IFR IN SHOWERS. LOW PROB FOR
ISO TSRA. THE THREAT FOR MVFR/IFR LINGERS...ESPECIALLY EASTERN
HALF OF THE AREA INTO THURSDAY.

FRIDAY INTO SUNDAY...HIGH CONFIDENCE FOR VFR.

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...HIGH CONFIDENCE THROUGH WEDNESDAY NIGHT.

SCA REMAINS POSTED THROUGH MOST OF TONIGHT DUE TO 25KT WINDS AND
ROUGH SEAS...AND EXTENDED THEM INTO WED NIGHT FOR OUTER WATERS
WHERE SEAS WILL TAKE LONGER TO SUBSIDE.

OUTLOOK...THURSDAY THROUGH SUNDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

THU...SCA WILL BE NEEDED. FRONTAL PASSAGE WITH WIND SHIFT FROM SW
TO NW. WINDS MAY GUST UP TO 30KTS AHEAD OF FRONT. THERE IS A
CHANCE OF SHOWERS WITH LOW PROB FOR ISO THUNDER. SEAS ABOVE 5 FT
WILL LINGER THROUGH THURSDAY AND INTO EARLY FRI.

FRI INTO SUNDAY...HIGH PRES BUILDS IN WITH DRY WEATHER AND GOOD VSBY.

$$
SYNOPSIS...EVT/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...DUNTEN
AVIATION...EVT/JWD
MARINE...EVT/JWD

AREA FORECAST DISCUSSION

NWS TAUNTON MA

116 PM EDT TUE APR 23 2013

.SYNOPSIS...
A COASTAL STORM TRACKING SOUTHEAST OF NANTUCKET WILL BRING A
CHILLY RAIN TO EASTERN NEW ENGLAND TODAY AND INTO TONIGHT. DRIER
AND MILD WEATHER ARRIVES WED. A QUICK MOVING COLD FRONT WILL PASS
THROUGH WED NIGHT INTO THURSDAY. MAINLY DRY AND SEASONABLY COOL
WEATHER RETURNS FRIDAY AND INTO THE WEEKEND THANKS TO A STRONG
HIGH PRESSURE SYSTEM.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
115 PM UPDATE...

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
ALL MODELS SHOW COASTAL LOW PRESSURE MOVING UP THROUGH 40N/70W AND
CONTINUING RAIN OVER OUR EASTERN AREAS. STABILITY
INDICES...ESPECIALLY THE TOTALS AND LI...SHOW POTENTIAL FOR
THUNDER OVER THE CAPE/ISLANDS AFTER MIDNIGHT AND EXTENDING OVER
EASTERN MASS/RI BY MORNING. SUCH CONVECTION WOULD INCREASE HOURLY
PCPN RATES AND INCREASE POOR DRAINAGE FLOODING POTENTIAL.

MODEL QPF CONTINUES TO FOCUS MOST OF THE PCPN OVER RI/EASTERN
MASS/MERRIMACK VALLEY OF NH. THIS CONSENSUS AND GEOGRAPHY...THE
WORCESTER HILLS...SUGGESTS A SHARP MOISTURE GRADIENT ON THE
WESTERN EDGE OF THE RAIN SHIELD.

THE LOW MOVES NORTHEAST TO THE MARITIMES LATE TUESDAY
NIGHT/WEDNESDAY. THE ECMWF AND GGEM ARE SLOWER IN DOING THIS THAN
ARE THE NAM AND GFS...BUT ALL SUGGEST A PERIOD OF DRYING AND
PARTIAL CLEARING ON WEDNESDAY. EQUIVALENT MIXING TEMPS OF 6-8C
WOULD SUPPORT MAX TEMPS IN THE UPPER 60S AND LOWER 70S.

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...

* COLD FRONT WILL PUSH THROUGH WED NIGHT INTO THURS
* WEAK WAVE ON FRIDAY
* STRONG HIGH PRESSURE FOR THE WEEKEND

DETAILS...

.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

CONDITIONS SHOULD LOWER TO IFR/LIFR OVERNIGHT...AGAIN ESPECIALLYNEAR
COAST. POSSIBILITY OF ISOLD THUNDER AROUND CAPE COD AND ISLANDS
FROM MIDNIGHT UNTIL 8 AM WED.

EXPECT RAPID IMPROVEMENT TO VFR WED MORNING...POSSIBLY NOT UNTIL
MIDDAY ALONG IMMEDIATE COAST. SHOULD HAVE SEA BREEZES DEVELOP
EARLY TO MID AFTERNOON...A LITTLE LATER THAN USUAL.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. COULD SEE LOWER
CIGS/VSBYS THAN FCST THIS EVENING.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...THURSDAY THROUGH SUNDAY...

FRIDAY INTO SUNDAY...HIGH CONFIDENCE FOR VFR.

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

OVERVIEW...MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY.

SMALL CRAFT ADVISORIES WILL CONTINUE INTO TONIGHT WITH EAST GUSTS
TO 30 KNOTS. THERE IS A LOW PROBABILITY OF GUSTS TO 35 KNOTS...BUT
NOT ENOUGH TO GO WITH GALES AT THIS TIME.

COASTAL LOW PRESSURE OFF THE CAROLINAS WILL MOVE UP THE COAST
TODAY AND TONIGHT. PERIODS OF HEAVY RAIN WILL REDUCE VSBYS ON THE
WATERS. WINDS SHIFT FROM EAST THROUGH NORTH TO WEST AS THE COASTAL
LOW PASSES OFFSHORE LATER TONIGHT AND WEDNESDAY. SMALL CRAFTS
LINGER ON THE SOUTHERN AND OUTER WATERS THROUGH WEDNESDAY EVENING.

BUILDING SEAS TODAY WITH ROUGH SEAS CONTINUING THROUGH WEDNESDAY.

OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

WED NIGHT INTO THU...SCA WILL BE NEEDED. FRONTAL PASSAGE WITH WIND
SHIFT FROM SW TO NW. WINDS MAY GUST UP TO 30KTS AHEAD OF FRONT.
THERE IS A CHANCE OF SHOWERS WITH LOW PROB FOR ISO THUNDER. SEAS
ABOVE 5 FT WILL LINGER THROUGH THURSDAY AND INTO EARLY FRI.

FRI INTO SUNDAY...HIGH PRES BUILDS IN WITH DRY WEATHER AND GOOD VSBY.

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR ANZ230-
232>234-236.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ231-251.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT THURSDAY FOR ANZ235-237-
250-254>256.

$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...JWD
SHORT TERM...WTB
LONG TERM...DUNTEN
AVIATION...JWD
MARINE...WTB/DUNTEN

AREA FORECAST DISCUSSION

NWS CHARLESTON SC

737 PM EDT WED APR 24 2013

.SYNOPSIS...
A WEAKENING COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY...WITH
HIGH PRESSURE BRIEFLY BUILDING IN ITS WAKE FRIDAY THROUGH
SATURDAY. UNSETTLED WEATHER IS LIKELY INTO THE MIDDLE OF NEXT WEEK.

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A COLD FRONT IS EXPECTED TO MOVE INTO THE FORECAST AREA AFTER MIDNIGHT.
REGIONAL RADARS INDICATING PRE-FRONTAL PATCHES OF LIGHT RAIN MOVING
INTO UPSTATE SOUTH CAROLINA WITH SPOTTY AND SHALLOW CONVECTIVE
RAINS BACK INTO SW GEORGIA AT SUNSET. AS THE FRONT APPROACHES...
WINDS BELOW 850 MB WILL VEER TO SOUTHWEST...ALIGNING THE FLOW
PARALLEL TO THE FRONT. THIS IN TURN WILL WEAKEN UPLIFT ALONG THE
LEADING EDGE OF THE FRONT...RESULTING IN A DIMINISHING PRECIP BAND
WITH THE BOUNDARY. A LOT OF THE GUIDANCE HAS CONTINUED WITH A
DRYING TREND...SOME OF THEM NOT REALLY SHOWING ANY MEASURABLE
PRECIP OVER OUR AREA TONIGHT. WE DID NOT DEVIATE FROM ONGOING
FORECAST OF ISOLATED SHOWERS AFTER MIDNIGHT...BUT RECENTLY UPDATED
OUR FORECAST TO ADD SLIGHT CHANCE POPS INTO OUR INLAND GEORGIA
ZONES LATE THIS EVENING PER LATEST RAP GUIDANCE AND RADAR TRENDS.
EXTENSIVE MID AND HIGH CLOUDS MOVING IN COMBINED WITH A FEW KNOTS
OF WIND OVERNIGHT WILL MODERATE LOW TEMPS...KEEPING THEM FROM
DROPPING BELOW THE UPPER 50S.

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...THE WEAKENING COLD FRONT WILL BE SINKING SOUTH/SOUTHEAST
THROUGH THE FORECAST AREA BY DAYBREAK...QUICKLY SHIFTING OFFSHORE AS
THE MORNING PROGRESSES. THE FRONT WILL HAVE OUTRUN UPPER LEVEL
TROUGHING THAT WILL BE DAMPENING UPON APPROACH TO THE EAST COAST BY
THE AFTERNOON HOURS. DELAYED SHORTWAVE ENERGY WILL BE CONSIDERABLY
WEAKER...AND DEEP MOISTURE WILL BE STEADILY DIMINISHING THROUGH THE
DAY. CONFIDENCE CONTINUES TO DECREASE IN THE COVERAGE AND DURATION
OF RAIN WITH THE FRONTAL PASSAGE...AS NUMERICAL MODEL SOLUTIONS
DOWNPLAY THE MOISTURE WITH THIS SYSTEM. WILL THUS CONTINUE TO CAP
RAIN CHANCES BELOW 30 PERCENT INTO THE AFTERNOON...BEFORE DECREASING
POPS BELOW 15 PERCENT BY SUNSET. INSTABILITY ALSO APPEARS QUITE
LIMITED TO NEARLY NON-EXISTENT DEPENDING ON MODEL SOLUTION...AND
HAVE CONFINED MENTION OF A SLIGHT CHANCE FOR THUNDER TO A FEW HOURS
IN THE EARLY TO MID AFTERNOON. CONSIDERING THICK CLOUD COVER
SUPPRESSING DIURNAL WARMING...THE RESULTING LOW INSTABILITY...AND
ONLY WEAK UPPER LEVEL SUPPORT WITHIN DAMPENING FEATURES
ALOFT...SUBSEQUENT FORECAST SHIFTS MAY CONSIDER REMOVING MENTION OF
THUNDER ALL TOGETHER PER MODEL TRENDS. AS SURFACE FLOW VEERS AROUND
TO THE NORTH/NORTHEAST LATE IN THE DAY...EXPECT HIGH TEMPERATURES TO
RANGE FROM THE MID 70S NORTH TO AROUND 80 DEGREES SOUTH AROUND THE
ALTAMAHA RIVER. CLEARING SKIES AND LIGHT NORTHEAST FLOW BEHIND THE
FRONT OVERNIGHT WILL SUPPORT NOTABLY COOLER LOW
TEMPERATURES...REACHING THE UPPER 40S INLAND TO THE LOWER 50S
ALONG THE COAST.

FRIDAY...SURFACE HIGH PRESSURE WILL RAPIDLY BUILD INTO THE
REGION...AS NEARLY ZONAL FLOW ALOFT TRANSITIONS INTO WEAK UPPER
RIDGING BY THE NIGHTTIME HOURS. THE DAYTIME HOURS WILL BE MOSTLY
SUNNY TO PARTLY CLOUDY AND RAIN FREE. HIGH TEMPERATURES WILL BE A
FEW DEGREES BELOW SEASONAL AVERAGES WITHIN CONTINUED NORTHEAST/EAST
FLOW...RANGING FROM THE MID 70S NORTH TO THE UPPER 70S SOUTH.
THERE DOES APPEAR TO BE SOME MODEL DISCREPANCY FRIDAY NIGHT IN THE
REPRESENTATION OF SHORTWAVE ENERGY TRACKING INTO THE REGION FROM
THE WEST. THE MORE AGGRESSIVE ECMWF SOLUTION INTRODUCES RAIN
ACROSS THE WESTERN FORECAST AREA BETWEEN MIDNIGHT AND DAYBREAK
SATURDAY...WHILE THE DRIER NAM AND GFS SOLUTIONS ACTUALLY INDICATE
NEGATIVE VORTICITY ADVECTION WITHIN THE WEAK RIDGE ALOFT. WILL
SHOW INCREASING CLOUD COVER OVERNIGHT...YET KEEP RAIN CHANCES AT
OR BELOW 10 PERCENT THROUGH FRIDAY DUE TO MODEL INCONSISTENCIES.

SATURDAY...A MORE UNSETTLED PATTERN BEGINS TO TAKE SHAPE BY THE
EARLY WEEKEND...AS SHORTWAVE ENERGY MOVES EASTWARD ALONG THE GULF
COAST STATES. DEEP MOISTURE WILL INCREASE OVER THE AREA
ACCORDINGLY...WHILE SURFACE HIGH PRESSURE STEADILY SLIPS OFF THE
EAST COAST. WILL INDICATE RAIN CHANCES INCREASING FROM WEST TO
EAST...WITH THE BEST COVERAGE LIKELY DELAYED UNTIL THE AFTERNOON
HOURS. LOW LEVEL INSTABILITY WILL BE NEGLIGIBLE ACROSS THE MAJORITY
OF THE FORECAST AREA...WITH ONLY THE ECMWF SHOWING WEAK INSTABILITY
DEVELOPING JUST SOUTH OF THE GEORGIA ZONES DURING THE AFTERNOON.
PREFER TO MAINTAIN JUST A SLIGHT CHANCE FOR THUNDER AS A RESULT.
THICK CLOUD COVER AND A PERSISTENT ONSHORE FLOW WILL SUPPRESS HIGH
TEMPERATURES IN THE LOW 70S SOUTH CAROLINA ZONES TO THE UPPER 70S
SOUTHEAST GEORGIA COUNTIES.

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
UNSETTLED WEATHER IS EXPECTED DURING THIS PERIOD. CONSIDERABLE
MODEL DIFFERENCES EXIST WHICH RESULTS IN LOWER THAN NORMAL FORECAST
CONFIDENCE WITH REGARD TO RAIN CHANCES AND HIGH TEMPERATURES. IT
DOES APPEAR QUITE LIKELY THAT THIS WILL BE AT THE LEAST A VERY
CLOUDY PERIOD.

.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
AS A COLD FRONT APPROACHES OVERNIGHT...CLOUDS WILL REMAIN MAINLY
ABOVE 4 KFT WITH LAYERED CLOUDS IN THE MID/UPPER LEVELS. POTENTIAL
FOR MVFR CEILINGS ASSOCIATED WITH THE FRONT WILL INCREASE NEARING
DAYBREAK ALONG WITH A RISK FOR ISOLATED SHOWERS...BUT CONFIDENCE
STILL REMAINS TOO LOW TO INCLUDE IN THE TAFS. ON THU...VFR
CONDITIONS EXPECTED TO PREVAIL WITH MOST OF THE MOISTURE AND
CLOUDS IN THE 3500 FT TO 7 KFT LAYER. SURFACE WINDS SHOULD VEER
MORE N ON THU AS THE FRONT SAGS TO THE S. CANNOT COMPLETELY RULE
OUT AN AFTERNOON SHOWER AS THE SEA BREEZE INTERACTS...HOWEVER
COVERAGE LOOKS TO BE EXTREMELY SPOTTY.

EXTENDED AVIATION OUTLOOK...MAINLY VFR THU NIGHT INTO FRI NIGHT.
A PERIOD OF POSSIBLE OR OCCASIONAL FLIGHT RESTRICTIONS WILL OCCUR
SATURDAY AFTERNOON/EVENING AND CONTINUE THROUGH SUNDAY.

.MARINE...
QUIET CONDITIONS TONIGHT WITH WINDS INCREASING OUT OF THE
SW...EVENTUALLY TURNING TO THE WEST AROUND DAYBREAK THURSDAY. A
WEAKENING FRONT IS EXPECTED TO MOVE THROUGH THE WATERS BY THURSDAY
AFTERNOON...WITH HIGH PRESSURE BUILDING BACK INTO THE REGION BY
FRIDAY. MARGINAL SMALL CRAFT ADVISORY CONDITIONS WITHIN A SLIGHT
NORTHEAST SURGE WILL BE POSSIBLE FRIDAY IN THE WAKE OF THE
FRONT...ESPECIALLY ACROSS THE WATERS 20 TO 60 NM OFF THE GEORGIA
COAST. EAST TO SOUTHEAST WINDS AT OR BELOW 15 KT...WITH SEAS AT OR
BELOW 5 FT...SHOULD PREVAIL SATURDAY THROUGH MONDAY.

RIP CURRENTS...SWELL ENERGY AROUND 2 TO EVEN 3 FT WITH A 9 TO 10
SECOND PERIOD WILL CONTINUE TO IMPACT THE BEACHES THROUGH
THURSDAY. WHEN CONSIDERING THE ADDITIONAL EFFECTS FROM THE
APPROACHING FULL MOON AND SOME ONSHORE FLOW AROUND 15 MPH...A
MODERATE RISK OF RIP CURRENTS WILL CONTINUE FOR ALL OF THE LOCAL
BEACHES THURSDAY.

.TIDES/COASTAL FLOODING...
HIGH TIDES ASSOCIATED WITH THE FULL MOON AND LUNAR PERIGEE
/PERIGEAN SPRING TIDES/ WILL BE HIGHER THAN PREDICTED/NORMAL FROM
LATE THURSDAY THROUGH MONDAY...AS A NORTHEAST AND EVENTUALLY EAST
WIND DEVELOPS. THERE IS A SMALL CHANCE THAT SHALLOW COASTAL FLOODING
COULD OCCUR WITH THE HIGHER OF THE DAILY HIGH TIDES...AND THUS
COASTAL FLOOD ADVISORIES ARE POSSIBLE.

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

SYNOPSIS...
NEAR TERM...
SHORT TERM...WMS
LONG TERM...MTE
AVIATION...
MARINE...JRL/WMS
TIDES/COASTAL FLOODING...

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

739 AM EDT TUE APR 23 2013

.SYNOPSIS...
A PRESSURE RIDGE WILL EXTEND THROUGH THE FORECAST AREA THROUGH
TONIGHT. A COLD FRONT WILL APPROACH FROM THE WEST WEDNESDAY. THE
WEAKENING FRONT WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT AND
EARLY THURSDAY.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO RIDGE INTO THE FORECAST AREA FROM
THE NORTH TODAY. CLOUDINESS ASSOCIATED WITH THE OFFSHORE FRONT
WAS AFFECTING MAINLY THE NORTHEAST PART OF THE FORECAST AREA
EARLY THIS MORNING. THE LATEST RAP SHOWS HIGH LOW-LEVEL MOISTURE
CONTINUING IN THE NORTHEAST PART THROUGH 15Z. EXPECT THIS
CLOUDINESS WILL DIMINISH LATER THIS MORNING OR EARLY THIS
AFTERNOON AS THE FRONT SHIFTS FARTHER OFFSHORE. HEATING AND MIXING
SHOULD ALSO RESULT IN LESS CLOUDINESS. THE TEMPERATURE GUIDANCE
WAS CLOSE. THE GUIDANCE MAY BE A LITTLE TOO WARM IN THE NORTHEAST
PART BECAUSE OF LINGERING CLOUDINESS.

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
THE RIDGE WILL REMAIN NEAR THE FORECAST AREA TROUGH TONIGHT.
EXPECT STRONG NET RADIATIONAL COOLING WHICH MAY LEAD TO AREAS OF
FOG DURING THE EARLY MORNING HOURS. WARMING WILL OCCUR AHEAD OF
THE APPROACHING COLD FRONT WEDNESDAY. THE WARM TEMPERATURE
GUIDANCE IS USUALLY BETTER JUST AHEAD OF A COLD FRONT. THE NAM
AND GFS AGREE KEEPING THE FORCING AND DEEPER MOISTURE WEST OF THE
FORECAST AREA AND EXPECT IT WILL REMAIN DRY WEDNESDAY. THE NAM AND
GFS SHOW THE FRONT MOVING INTO THE AREA WEDNESDAY NIGHT WITH
DIMINISHING MOISTURE. THE GUIDANCE CONSENSUS SUPPORTS CHANCE POPS.
THE NAM AND GFS INDICATE DRYING BEHIND THE FRONT THURSDAY.
HOWEVER...THE ECMWF HAD A SLOWER TIMING SO WE MAINTAINED A SMALL
POP THURSDAY. DRY RIDGING BEHIND THE FRONT SHOULD BE DOMINATE
THURSDAY NIGHT.

.LONG TERM /FRIDAY THROUGH MONDAY/...
THE DRY RIDGING SHOULD REMAIN IN CONTROL THROUGH FRIDAY. AN
ONSHORE FLOW AND ANOTHER FRONT IN THE AREA SUPPORTS A CHANCE OF
SHOWERS AND THUNDERSTORMS DURING THE REST OF THE MEDIUM-RANGE
PERIOD. THE GFS AND ECMWF MOS SUPPORT CHANCE POPS.

.AVIATION /12Z TUESDAY THROUGH SUNDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. LATEST SATELLITE LOOP INDICATING AN OVERCAST
LAYER OF CLOUDS THAT HAVE SPREAD IN FROM THE NORTHEAST OVERNIGHT.
THESE CLOUDS MAINLY AFFECTING THE TAF SITES OF CAE/CUB/DNL. EXPECT
HE MVFR CONDITIONS TO PERSIST FOR A COUPLE OF HOURS...WITH CLOUDS
BECOMING SCATTERED BY MID/LATE MORNING. SKIES SHOULD BECOME MOSTLY
CLEAR AFTER 00Z WEDNESDAY. OVERNIGHT...THE POTENTIAL EXIST FOR SOME
LIGHT FOG...HAVE NOT INCLUDED ANY AT THE TAF SITES AT THIS TIME DUE
TO LOW CONFIDENCE.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY NIGHT INTO EARLY THURSDAY WITH CIG/VSBY RESTRICTIONS
POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

640 AM EDT TUE APR 23 2013

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. LATEST SATELLITE LOOP INDICATING SOME MVFR CIGS
SPREADING ACROSS THE AREA EARLY THIS MORNING FROM THE EAST. MODELS
ALSO SUGGESTING SOME LOW LEVEL MOISTURE MOVING INTO THE REGION NEAR
EARLY THIS MORNING. WILL USE SOME MVFR CIGS IN TEMPOS WHERE
NECESSARY BEFORE SUNRISE. AFTER 12Z...VFR CONDITIONS ARE EXPECTED TO
CONTINUE WITH JUST SCATTERED CLOUDS AROUND 4 KFT. VBSYS EXPECTED TO
BE 7 MILES OR GREATER THE ENTIRE PERIOD WITH LOW LEVEL WINDS
EXPECTED TO KEEP LOWER LAYERS MIXED NOT ALLOWING FOR MUCH IF ANY FOG
TO DEVELOP NEAR SUNRISE THIS MORNING. SKIES SHOULD BECOME MOSTLY
CLEAR AFTER 00Z WEDNESDAY.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY WITH CIG/VSBY RESTRICTIONS POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

615 AM EDT TUE APR 23 2013

.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. LATEST SATELLITE LOOP INDICATING SOME MVFR CIGS
SPREADING ACROSS THE AREA EARLY THIS MORNING FROM THE EAST. MODELS
ALSO SUGGESTING SOME LOW LEVEL MOISTURE MOVING INTO THE REGION NEAR
EARLY THIS MORNING. WILL USE SOME MVFR CIGS IN TEMPOS WHERE
NECESSARY BEFORE SUNRISE. AFTER 12Z...VFR CONDITIONS ARE EXPECTED TO
CONTINUE WITH JUST SCATTERED CLOUDS AROUND 4 KFT. VBSYS EXPECTED TO
BE 7 MILES OR GREATER THE ENTIRE PERIOD WITH LOW LEVEL WINDS
EXPECTED TO KEEP LOWER LAYERS MIXED NOT ALLOWING FOR MUCH IF ANY FOG
TO DEVELOP NEAR SUNRISE THIS MORNING. SKIES SHOULD BECOME MOSTLY
CLEAR AFTER 00Z WEDNESDAY.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY WITH CIG/VSBY RESTRICTIONS POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

347 AM EDT TUE APR 23 2013

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO RIDGE INTO THE FORECAST AREA FROM
THE NORTH TODAY. CLOUDINESS ASSOCIATED WITH THE OFFSHORE FRONT
WAS AFFECTING THE NORTHEAST PART OF THE FORECAST AREA EARLY THIS
MORNING. THE LATEST RAP SHOWS HIGH LOW-LEVEL MOISTURE CONTINUING
IN THE NORTHEAST PART THROUGH 15Z. EXPECT THIS CLOUDINESS WILL
DIMINISH LATER THIS MORNING OR EARLY THIS AFTERNOON AS THE FRONT
SHIFTS FARTHER OFFSHORE. HEATING AND MIXING SHOULD ALSO RESULT IN
LESS CLOUDINESS. THE TEMPERATURE GUIDANCE WAS CLOSE. THE GUIDANCE
MAY BE A LITTLE TOO WARM IN THE NORTHEAST PART BECAUSE OF
LINGERING CLOUDINESS.

.AVIATION /08Z TUESDAY THROUGH SUNDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. LATEST SATELLITE LOOP INDICATING SOME MVFR CIGS
SPREADING ACROSS THE AREA EARLY THIS MORNING FROM THE EAST. MODELS
ALSO SUGGESTING SOME LOW LEVEL MOISTURE MOVING INTO THE REGION NEAR
EARLY THIS MORNING. WILL USE SOME MVFR CIGS IN TEMPOS WHERE
NECESSARY BEFORE SUNRISE. AFTER 12Z...VFR CONDITIONS ARE EXPECTED TO
CONTINUE WITH JUST SCATTERED CLOUDS AROUND 4 KFT. VBSYS EXPECTED TO
BE 7 MILES OR GREATER THE ENTIRE PERIOD WITH LOW LEVEL WINDS
EXPECTED TO KEEP LOWER LAYERS MIXED NOT ALLOWING FOR MUCH IF ANY FOG
TO DEVELOP NEAR SUNRISE THIS MORNING. SKIES SHOULD BECOME MOSTLY
CLEAR AFTER 00Z WEDNESDAY.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY WITH CIG/VSBY RESTRICTIONS POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

303 AM EDT TUE APR 23 2013

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO RIDGE INTO THE FORECAST AREA FROM
THE NORTH TODAY. CLOUDINESS ASSOCIATED WITH THE OFFSHORE FRONT
WAS AFFECTING THE NORTHEAST PART OF THE FORECAST AREA EARLY THIS
MORNING. THE LATEST RAP SHOWS HIGH LOW-LEVEL MOISTURE CONTINUING
IN THE NORTHEAST PART THROUGH 15Z. EXPECT THIS CLOUDINESS WILL
DIMINISH LATER THIS MORNING OR EARLY THIS AFTERNOON AS THE FRONT
SHIFTS FARTHER OFFSHORE. HEATING AND MIXING SHOULD ALSO RESULT IN
LESS CLOUDINESS. THE TEMPERATURE GUIDANCE WAS CLOSE. THE GUIDANCE
MAY BE A LITTLE TOO WARM IN THE NORTHEAST PART BECAUSE OF
LINGERING CLOUDINESS.

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. HOWEVER...MODELS SUGGEST SOME LOW LEVEL MOISTURE
MAY MOVE INTO THE REGION NEAR SUNRISE THIS MORNING. BOTH NAM AND
GFS3 FORECAST SOUNDINGS INDICATE SOME MOISTURE AROUND 2 KFT BUT DOES
NOT APPEAR ENOUGH FOR CEILINGS. MOISTURE APPEARS TO BE ADVECTED INTO
AREA ON NORTHEAST WINDS AT 20 KNOTS NEAR SUNRISE. NOT CONFIDENT
ENOUGH TO GO MVFR CEILINGS EARLY THIS MORNING...SO WILL GO JUST 2
KFT SCATTERED. LAMP METEOGRAMS TO SHOW A CEILING ABOUT 2 KFT BUT
STILL THINK SCATTERED CLOUDS WOULD BE A BETTER FORECAST. AFTER
12Z...VFR CONDITIONS ARE EXPECTED TO CONTINUE WITH JUST SCATTERED
CLOUDS AROUND 4 KFT. VBSYS EXPECTED TO BE 7 MILES OR GREATER THE
ENTIRE PERIOD WITH LOW LEVEL WINDS EXPECTED TO KEEP LOWER LAYERS
MIXED NOT ALLOWING FOR MUCH IF ANY FOG TO DEVELOP NEAR SUNRISE THIS
MORNING. SKIES SHOULD BECOME MOSTLY CLEAR AFTER 00Z WEDNESDAY.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY WITH CIG/VSBY RESTRICTIONS POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS COLUMBIA SC

141 AM EDT TUE APR 23 2013

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE WILL CONTINUE TO RIDGE INTO THE FORECAST AREA FROM
THE NORTH TODAY. CLOUDINESS ASSOCIATED WITH THE OFFSHORE FRONT
WAS AFFECTING THE NORTHEAST PART OF THE FORECAST AREA EARLY THIS
MORNING. THE LATEST RAP SHOWS HIGH LOW-LEVEL MOISTURE CONTINUING
IN THE NORTHEAST PART THROUGH 15Z. EXPECT THIS CLOUDINESS WILL
DIMINISH THIS AFTERNOON AS THE FRONT SHIFTS FARTHER OFFSHORE AND
MIXING CONTINUES. THE TEMPERATURE GUIDANCE WAS CLOSE. THE GUIDANCE
MAY BE A LITTLE TOO WARM IN THE NORTHEAST PART BECAUSE OF
LINGERING CLOUDINESS.

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
THE RIDGE WILL REMAIN NEAR THE FORECAST AREA TROUGH TONIGHT.
EXPECT STRONG NET RADIATIONAL COOLING WHICH MAY LEAD TO AREAS OF
FOG DURING THE EARLY MORNING HOURS. WARMING WILL OCCUR AHEAD OF
THE APPROACHING COLD FRONT WEDNESDAY. THE WARM TEMPERATURE
GUIDANCE IS USUALLY BETTER JUST AHEAD OF A FRONT. THE NAM AND GFS
AGREE KEEPING THE FORCING AND DEEPER MOISTURE WEST OF THE FORECAST
AREA AND EXPECT IT WILL REMAIN DRY WEDNESDAY. THE NAM AND GFS SHOW THE
FRONT MOVING INTO THE AREA WEDNESDAY NIGHT WITH DIMINISHING
MOISTURE. THE GUIDANCE CONSENSUS SUPPORTS CHANCE POPS. THE NAM AND
GFS INDICATE DRYING BEHIND THE FRONT THURSDAY. HOWEVER...THE ECMWF
HAD A SLOWER TIMING SO WE MAINTAINED A SMALL POP THURSDAY. DRY
RIDGING BEHIND THE FRONT SHOULD BE DOMINATE THURSDAY NIGHT.

.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTHWARD ACROSS
THE CAROLINAS TODAY INTO TONIGHT. MAINLY VFR CONDITIONS EXPECTED FOR
THE NEXT 24 HOURS. HOWEVER...MODELS SUGGEST SOME LOW LEVEL MOISTURE
MAY MOVE INTO THE REGION NEAR SUNRISE THIS MORNING. BOTH NAM AND
GFS3 FORECAST SOUNDINGS INDICATE SOME MOISTURE AROUND 2 KFT BUT DOES
NOT APPEAR ENOUGH FOR CEILINGS. MOISTURE APPEARS TO BE ADVECTED INTO
AREA ON NORTHEAST WINDS AT 20 KNOTS NEAR SUNRISE. NOT CONFIDENT
ENOUGH TO GO MVFR CEILINGS EARLY THIS MORNING...SO WILL GO JUST 2
KFT SCATTERED. LAMP METEOGRAMS TO SHOW A CEILING ABOUT 2 KFT BUT
STILL THINK SCATTERED CLOUDS WOULD BE A BETTER FORECAST. AFTER
12Z...VFR CONDITIONS ARE EXPECTED TO CONTINUE WITH JUST SCATTERED
CLOUDS AROUND 4 KFT. VBSYS EXPECTED TO BE 7 MILES OR GREATER THE
ENTIRE PERIOD WITH LOW LEVEL WINDS EXPECTED TO KEEP LOWER LAYERS
MIXED NOT ALLOWING FOR MUCH IF ANY FOG TO DEVELOP NEAR SUNRISE THIS
MORNING. SKIES SHOULD BECOME MOSTLY CLEAR AFTER 00Z WEDNESDAY.

EXTENDED AVIATION OUTLOOK...ANOTHER COLD FRONT WILL CROSS AREA LATE
WEDNESDAY WITH CIG/VSBY RESTRICTIONS POSSIBLE.

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1124 PM CDT MON APR 22 2013

.DISCUSSION...
ISSUED 842 PM CDT MON APR 22 2013

INITIAL BAND OF SHOWERS TO OUR WEST MAKING SLOW PROGRESS EAST INTO
EASTERN MISSOURI AND IOWA...BUT BASED ON OUR 00Z SOUNDING...MAY HAVE
A TOUGH TIME HOLDING TOGETHER AS IT MOVES INTO CENTRAL IL LATER THIS
EVENING. LEAD SHORTWAVE CLEARLY SEEN ON THE WATER VAPOR LOOP OUT OVER
THE MISSOURI RIVER BASIN AND WAS TRACKING STEADILY TO THE EAST. A
MUCH MORE POTENT UPPER WAVE WAS SEEN DIGGING SOUTHEAST INTO THE CENTRAL
ROCKIES AND THIS WAVE WILL BRING THE STEADIER RAINS INTO THE FORECAST
AREA ON TUESDAY/TUESDAY NIGHT. CURRENT SURFACE MAP SHOWING A BIT MORE
LOW LEVEL MOISTURE ACRS THE SOUTHERN PLAINS AHEAD OF THE STRONGER WAVE
AND THAT MOISTURE WILL CONTINUE TO STREAM NORTHEAST TOWARDS THE MIDWEST
ALONG AND JUST AHEAD OF A COLD FRONT...WHICH AT 00Z WAS LOCATED OVER
PARTS OF CENTRAL IOWA. QUITE A LARGE AREA OF SNOW ON THE BACKSIDE
OF THE SYSTEM AS LATE AFTERNOON AND EARLY EVENING TEMPERATURES STRUGGLE
THRU THE UPPER 20S TO LOWER 30S. CURRENT ZONE FORECAST HAS A VERY GOOD
HANDLE ON THE TRENDS THIS EVENING AND INTO THE OVERNIGHT HOURS...SO
OTHER THAN SOME MINOR ADJUSTMENTS TO THE HOURLY TEMP GRIDS...NO OTHER
CHANGES WILL BE NEEDED THAT WOULD WARRANT A ZFP UPDATE AT THIS TIME.

.AVIATION...
ISSUED 1115 PM CDT MON APR 22 2013

TIMING OF RAIN AND LOWER CIGS INTO THE FORECAST AREA THE MAIN
FORECAST CHALLENGE THIS PERIOD. SATELLITE AND OBSERVATIONAL DATA
OUT TO OUR WEST SUGGESTS A SLOWER TRANSITION TO MVFR CIGS ON
TUESDAY AS THE INITIAL WAVE THAT IS BRINGING THE LIGHT SHOWER
ACTIVITY INTO THE AREA LATE THIS EVENING IS ENCOUNTERING A RATHER
DRY AIR MASS. HOWEVER...WITH THE SECOND WAVE FORECAST TO PUSH INTO
THE AREA ON TUESDAY...WE SHOULD SEE DETERIORATING CONDITIONS PUSH
IN DURING THE DAYLIGHT HOURS WHEN CIGS SHOULD LOWER TO MVFR WITH
SOME TEMPO IFR CONDITIONS...ESP IN THE AFTERNOON AND EVENING AND
EVENING. WILL CONTINUE TO INCLUDE VCSH OVERNIGHT...WITH THE STEADIER
RAINS AND ISOLD TSRA MOVING IN BY LATE TOMORROW MORNING OR EARLY
AFTERNOON AS THE COLD FRONT TRACKS ACRS THE AREA. SFC WINDS AHEAD
OF THE FRONT WILL BE OUT OF A SOUTHERLY DIRECTION TONIGHT INTO
TUESDAY MORNING...BUT THEN SWITCH INTO THE NORTHWEST ONCE THE FRONT
MOVES THRU...WHICH LOOKS TO BE FROM 14-16Z AT PIA....15Z-17Z AT
SPI AND BMI...AND FINALLY BY 21Z OUT EAST AT CMI. LOOK FOR THE MVFR
WITH TEMPO IFR CIGS TO CONTINUE INTO THE EVENING HOURS WELL BEHIND
THE FRONT WITH THE RAIN GRADUALLY COMING TO AN END IN THE EVENING.

SMITH
&&

.PREV DISCUSSION...
ISSUED 259 PM CDT MON APR 22 2013

MAIN WEATHER STORY CONTINUES TO BE THE RAIN EVENT COMING INTO THE
PICTURE LATE TONIGHT THROUGH TUESDAY NIGHT.

19Z/2PM SURFACE MAP SHOWS HIGH PRESSURE EXTENDING FROM NEW ENGLAND
TO THE WESTERN GULF OF MEXICO. FURTHER NORTHWEST...LOW PRESSURE IS
CENTERED NEAR HUDSON BAY...WITH STRONG COLD FRONT TRAILING
SOUTHWESTWARD INTO THE CENTRAL PLAINS. ALOFT...LARGE RIDGE IS IN
PLACE OVER THE EASTERN PACIFIC...WHILE A VIGOROUS SHORT-WAVE
DROPPING INTO THE CENTRAL ROCKIES IS BEGINNING TO DIG A TROUGH
DOWNSTREAM ACROSS THE CENTRAL CONUS.

SHORT TERM...TONIGHT THROUGH THURSDAY

LEAD SHORT-WAVE CURRENTLY EVIDENT ON WATER VAPOR IMAGERY OVER
WESTERN NEBRASKA/KANSAS WILL TRACK EASTWARD THIS EVENING. CLUSTER
OF THUNDERSTORMS ASSOCIATED WITH THIS FEATURE WEST OF KANSAS CITY
WILL SHIFT EASTWARD AND WEAKEN WITH TIME AS IT ENCOUNTERS A MUCH
DRIER AIRMASS FURTHER EAST ACROSS ILLINOIS. 3KM HRRR SHOWS REMNANTS
OF THIS CONVECTION TRYING TO WORK ITS WAY INTO WEST-CENTRAL
ILLINOIS BETWEEN 00Z AND 03Z...HOWEVER QPF AMOUNTS ARE PALTRY.
BASED ON INITIALLY VERY DRY FORECAST SOUNDINGS...THINK THIS FIRST
WAVE WILL DO LITTLE MORE THAN TO MOISTEN THE AIRMASS FOR THE MAIN
WAVE ON TUESDAY. HAVE THEREFORE DOWNPLAYED RAIN CHANCES EARLY
TONIGHT...FEATURING ONLY LOW CHANCE POPS FOR SHOWERS WEST OF I-55
THROUGH MIDNIGHT. RAIN CHANCES BEGIN TO INCREASE OVERNIGHT...AS
MAIN WAVE AND ASSOCIATED COLD FRONT APPROACHES FROM THE WEST.
SOUNDINGS SHOW AT LEAST MODEST ELEVATED INSTABILITY...SO WILL
MENTION CHANCE FOR THUNDER AFTER MIDNIGHT.

FRONTAL BOUNDARY SLOWLY PUSHES EASTWARD THROUGH CENTRAL ILLINOIS
ON TUESDAY...WITH SURFACE LOW PRESSURE EXPECTED TO RIDE ALONG THE
BOUNDARY AS IT DOES SO. COMBINATION OF STRONG LOW-LEVEL FORCING
ALONG FRONT...VIGOROUS UPPER DYNAMICS COMING IN FROM THE WEST...AND
INCREASINGLY DEEP MOISTURE WITH PRECIPITABLE WATER VALUES
EXCEEDING 1 INCH...WILL LEAD TO THE DEVELOPMENT OF WIDESPREAD
SHOWERS AND THUNDERSTORMS ACROSS THE AREA. AM NOT ANTICIPATING
SEVERE WEATHER...HOWEVER A FEW STRONG THUNDERSTORMS WILL BE
POSSIBLE EAST OF I-55 DURING THE AFTERNOON. BEST INSTABILITY AND
SHEAR PARAMETERS WILL REMAIN FOCUSED A BIT FURTHER SOUTHWEST
ACROSS THE OZARKS AND LOWER OHIO RIVER VALLEY.

ONCE SURFACE LOW LIFTS INTO THE GREAT LAKES...FRONT WILL GET
PULLED EASTWARD INTO INDIANA BY EARLY EVENING. ALL OPERATIONAL
MODELS SUGGEST PLENTY OF SHOWERS LINGERING BEHIND THE BOUNDARY AT
LEAST THROUGH MIDNIGHT. HAVE THEREFORE MAINTAINED HIGH POPS
THROUGH THE EVENING...WITH STEADILY DECREASING CHANCES AFTER
MIDNIGHT. MAY EVEN BE ENOUGH COLD AIR ADVECTING INTO THE AREA
BEHIND THE FRONT TO CHANGE THE RAIN SHOWERS TO A BRIEF PERIOD OF
SNOW SHOWERS ACROSS THE ILLINOIS RIVER VALLEY OVERNIGHT...HOWEVER
THINK MOST OF THE MOISTURE WILL DEPART BEFORE IT GETS COLD ENOUGH
FOR THAT TO HAPPEN. WILL HOWEVER MENTION JUST A SLIGHT CHANCE FOR
SNOW SHOWERS ACROSS THE FAR WESTERN KILX CWA IN CASE MOISTURE
LINGERS. TOTAL RAINFALL FROM THIS SYSTEM WILL GENERALLY BE BETWEEN
THREE QUARTERS AND ONE INCH...HOWEVER AMOUNTS IN EXCESS OF ONE
INCH WILL BE LIKELY EAST OF I-55 WHERE A FEW STRONGER STORMS MAY OCCUR.

MUCH COOLER/DRIER AIRMASS WILL ARRIVE ON WEDNESDAY AND
THURSDAY...WITH HIGHS DROPPING BACK INTO THE 50S AND OVERNIGHT
LOWS DIPPING INTO THE 30S. MODELS STILL SHOW A NORTHERN-STREAM
SHORT-WAVE TRACKING ACROSS THE UPPER MIDWEST AND GREAT LAKES
WEDNESDAY NIGHT...HOWEVER THINK MOISTURE WILL BE LACKING AND
STRONGEST LIFT WILL REMAIN WELL TO THE NORTH. HAVE THEREFORE ONLY
MENTIONED A CHANCE FOR SPRINKLES/FLURRIES FROM THE PEORIA AREA
NORTHWARD.

LONG TERM...FRIDAY THROUGH MONDAY

MODELS CONTINUE TO STRUGGLE WITH THE POTENTIAL SYSTEM AT THE END
OF THE WEEK. SYSTEM IN QUESTION IS A CUT-OFF LOW OFF THE COAST OF
SOUTHERN CALIFORNIA THAT WILL EVENTUALLY GET ABSORBED INTO THE
PREVAILING W/NW FLOW ACROSS THE CONUS AND GET EJECTED EASTWARD BY
FRIDAY/SATURDAY. GFS HAS CONSISTENTLY BEEN FASTER AND FURTHER
NORTH WITH ITS TRACK...SPREADING RAIN INTO CENTRAL ILLINOIS
FRIDAY/FRIDAY NIGHT. MEANWHILE...ECMWF HAS BEEN CONSISTENTLY
SLOWER AND FURTHER SOUTH...KEEPING MUCH OF THE RAIN ACROSS THE
TENNESSEE AND OHIO RIVER VALLEYS ON SATURDAY/SUNDAY. GEM SUPPORTS
THE SLOWER ECMWF...SO WILL TREND TOWARD THIS SOLUTION FOR THE
EXTENDED. AS A RESULT...HAVE OPTED TO KEEP FRIDAY DRY...WITH LOW
CHANCE POPS ARRIVING FRIDAY NIGHT. AFTER THAT...HAVE CONFINED RAIN
CHANCES TO MAINLY THE SOUTHERN CWA ON SATURDAY...WITH MAIN FOCUS
FOR MORE SIGNIFICANT RAINFALL REMAINING SOUTH OF THE AREA.

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS DES MOINES IA

652 PM CDT WED APR 24 2013

.SHORT TERM.../TONIGHT /...
ISSUED AT 419 PM CDT WED APR 24 2013

FORECAST CONCERN FOR LATE AFTERNOON AND TONIGHT WILL REVOLVE AROUND
PRECIPITATION CHANCES. APPROACHING COLD FRONT WITH STRONG PV
ANOMALY...CURRENTLY LEADING TO PRECIPITATION IN SOUTH DAKOTA...WILL
SPREAD SE INTO IOWA THIS EVENING. SYSTEM WILL BE QUICK MOVING...AND
ANTICIPATE BAND OF SHOWERS TO SWEEP QUICKLY ACROSS THE
AREA...SIMILAR TO HRRR TIMING/TREND. WITH SKIES REMAINING CLEAR
ACROSS CENTRAL IOWA...NO CU FIELD NOTED...AND HIGH DEW POINT
DEPRESSIONS...DO NOT ANTICIPATE DEVELOPMENT AHEAD OF LINE.
HOWEVER...SOME MU CAPE WILL LEAD TO ISOLATED THUNDER NEAR FRONT.
PRECIPITATION ENDS QUICKLY BEHIND FROPA WITH SUBSIDENCE. HAVE KEPT
TEMPERATURES COOLER ACROSS THE NORTH ESPECIALLY...DROPPING OFF
QUICKLY BEHIND FROPA...MAY SEE SOME LIGHT RN/SN MIX ACROSS THE NORTH
AFTER MIDNIGHT WITH ANY LINGERING PRECIPITATION.

.LONG TERM.../THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 419 PM CDT WED APR 24 2013

A FAIRLY QUIET...AND MUCH...MUCH WARMER WEATHER PATTERN IS SETTING
UP ACROSS THE MIDWEST FOR THE NEXT COUPLE OF DAYS. UNDER THE
INFLUENCE OF HIGH PRESSURE...THURSDAY AFTERNOON LOOKS TO BE VERY
SIMILAR TO WEDNESDAY...JUST A FEW DEGREES WARMER AND A FEW MORE
CLOUDS.

HEADING INTO FRIDAY...A NOTABLE THERMAL RIDGE WILL BEGIN TO BUILD
ALL THE WAY UP OVER THE DAKOTAS AND INTO CANADA. 850MB TEMPERATURES
LOOK TO MAKE IT UP TO AROUND 8C...SETTING UP THE POTENTIAL FOR SOME
OF THE WARMEST TEMPERATURES THUS FAR OF 2013 TO BE ADVECTED INTO THE
CWA...WHEN THE THERMAL RIDGE SHIFTS EASTWARD BEGINNING SATURDAY.
STICKING TO FRIDAY...A WEAK SURFACE TROUGH WILL PUSH THROUGH THE
MIDWEST. THE GFS AND NAM BOTH HINT AT CAPE VALUES MAKING IT TO
AROUND 300 J/KG...BUT WINDS ALOFT ARE QUITE WEAK...AND THE BOUNDARY
ITSELF IS FAIRLY WEAK...SO NOT MUCH PRESENT IN TERMS OF FOCUSING
MECHANISMS TO GENERATE ANY CONFIDENCE IN THUNDERSTORM DEVELOPMENT.

SATURDAY AND SUNDAY...BOTH DAYS SHOULD BE SIMILAR WEATHER WISE AS
THE AFOREMENTIONED THERMAL RIDGE SHIFTS EASTWARD. 850 MB TEMPS WILL
GO FROM AROUND 8C IN CENTRAL IOWA...TO AROUND 10C ON SATURDAY...TO
AROUND 14C ON SUNDAY. LOTS OF DRY AIR ALOFT WILL SUPPORT MAINLY
SUNNY SKIES ON BOTH SATURDAY AND SUNDAY.

THE WEATHER PATTERN CHANGES AS WE HEAD INTO MONDAY AND TUESDAY. WE
WILL BE WATCHING FOR THE POTENTIAL FOR AFTERNOON THUNDERSTORMS ON
BOTH DAYS. AS OF NOW...TUESDAY LOOKS LIKE THE BETTER OF THE TWO DAYS
FOR THUNDERSTORM DEVELOPMENT. AS A SIZABLE AREA OF LOW PRESSURE SETS
UP TO MOVE THROUGH THE DAKOTAS...MONDAY FEATURES A WARM FRONT
PASSING THROUGH IOWA TOWARDS WISCONSIN. THERE IS SOME INSTABILITY
EXPECTED AS WE WILL CERTAINLY BE UNDER THE WAA ADVECTION OF THE
THERMAL RIDGE...BUT AS OF NOW...IT APPEARS THE CAP WILL BE DIFFICULT
TO BREAK. FOR TUESDAY INTO WEDNESDAY...A COLD FRONT IS PROGGED TO
PASS THROUGH IOWA. THE GFS SEEMS TO BE A BIT FAST VERSUS THE REST OF
THE MODELS...SO ARE TRENDING THE PASSING OF THE FROPA BACK INTO
WEDNESDAY.

.AVIATION...25/00Z
ISSUED AT 649 PM CDT WED APR 24 2013

LINE OF SHOWERS AND ISOLATED THUNDERSTORMS MOVING ACROSS THE
STATE. WILL AFFECT THE NWRN TAFS IMMEDIATELY...PROGRESSING
SOUTHEAST ACROSS THE TAF SITES AND ENDING BEFORE 06Z IN KOTM.
SURFACE WIND GUSTS TO AROUND 45 KTS POSSIBLE WITH THE STORMS. SOME
MVFR STRATOCU WILL SPILL INTO THE NERN TAF SITES...OTHERWISE TAFS
WILL BE VFR THROUGH THE PERIOD. HIGH PRESSURE RIDGE WILL PASS OVER
THE STATE THU WITH WINDS BECOMING SOUTHWEST TO SOUTH LATE.

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...AWB
LONG TERM...KOTENBERG
AVIATION...MS APR 13

AREA FORECAST DISCUSSION

NWS GOODLAND KS

535 PM MDT WED APR 24 2013

.UPDATE...
ISSUED AT 340 PM MDT WED APR 24 2013

SURFACE OBSERVATIONS INDICATE A NARROW CORRIDOR OF LOWER DEW
POINTS FROM AROUND IMPERIAL SOUTHEAST TO HILL CITY. WITH NORTHWEST
WINDS GUSTING TO 30 MPH AS THE SURFACE TROUGH MOVES THROUGH AND
RELATIVE HUMIDITIES FALLING TO AROUND 15 PERCENT...AM THINKING THERE WILL
BE BRIEF PERIODS OF CRITICAL FIRE WEATHER CONDITIONS THIS
AFTERNOON. BEHIND THE SURFACE TROUGH OVER SOUTHWEST NEBRASKA
TEMPERATURES APPEAR TO BE COOLING SOME. THE INCREASING CLOUD
COVER MAY ALSO HELP THE WIND GUSTS TO DECREASE BELOW 30 MPH. WITH
ALL THIS IN MIND AND THAT CRITICAL FIRE WEATHER CONDITIONS ARE
JUST BEING REALIZED AT MID AFTERNOON...AM NOT CONFIDENT ENOUGH TO
ISSUE A FIRE WEATHER HIGHLITE FOR THE NORTHEAST PART OF THE AREA.
HOWEVER...SINCE THIS AREA DID NOT RECEIVE MUCH SNOW FROM THE
RECENT STORM...THE FUELS MAY BE DRY ENOUGH FOR CRITICAL FIRE
WEATHER CONDITIONS SO HAVE ISSUED AN SPS MENTIONING THE BRIEF
THREAT.

.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 101 PM MDT WED APR 24 2013

EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW BROAD TROUGH
CENTERED OVER GREAT LAKES REGION WITH W/NW FLOW ACROSS THE NORTHERN
AND CENTRAL PLAINS. A SHORTWAVE TROUGH IS CURRENTLY OVER EASTERN
WYOMING EXTENDING ACROSS THE GREAT BASIN.

THIS THIS FEATURE IS PROGGED TO SPLIT WITH THE MAIN ENERGY ALOFT
REMAINING NORTH OF OUR CWA. VERY STEEP LOW LEVEL LAPSE RATES AND
WEAK FORCING AHEAD OF THIS FEATURE HAVE PRODUCED HIGH BASED
VIRGA/LIGHT SHOWERS OVER PARTS OF NORTH CENTRAL NEBRASKA WITH A CU
FIELD EXTENDING SOUTH WHERE FURTHER DEVELOPMENT IS POSSIBLE. WHILE
I COULDNT RULE OUT A FEW SPRINKLES OR VIRGA THIS AFTERNOON/EARLY
EVENING CONFIDENCE IS LOW IN MEASURABLE.

SUBSIDENCE SHOULD OVERSPREAD THE REGION OVERNIGHT...WITH CLEARING
SKIES AND LIGHT AND VARIABLE WINDS. LEE TROUGH BUILDING OVER SE
COLORADO AND WESTERLY FLOW ALOFT WILL SUPPORT MODERATING AIR MASS
OVER OUR CWA BEGINNING TONIGHT. OVERNIGHT LOWS (WHILE BELOW NORMAL)
SHOULD BE WARMER THAN THE LAST FEW NIGHTS WITH VALUES IN THE UPPER
20S/LOW 30S (COLDEST IN PROXIMITY TO LINGERING SNOW PACK). TEMPS
ALOFT CONTINUE TO MODERATE THROUGH THE DAY THURSDAY. ITS HARD TO SAY
IF WE WILL STILL HAVE ANY EFFECT FROM SNOW PACK OR NOT (WHAT IS LEFT
AFTER MELTING THIS AFTERNOON). FOR NOW I STAYED IN LINE WITH
PREVIOUS FORECASTS WITH HIGHS IN THE LOW 60S WHERE SNOW PACK IS AND
UPPER 60S/LOW 70S ELSEWHERE.

A SHORTWAVE TROUGH IS PROGGED TO MOVE INTO THE SOUTHERN ROCKIES
THURSDAY AFTERNOON...WITH CLOUDS INCREASING FROM THE WEST/SOUTHWEST.
A FEW HIGH BASED SHOWERS/ISOLATED THUNDERSTORMS MAY DEVELOP OVER THE
HIGHER TERRAIN OF COLORADO...WHICH COULD SNEAK INTO WESTERN PORTIONS
OF OUR CWA DURING THE LATE AFTERNOON HOURS. CONFIDENCE IS GENERALLY
LOW ON MEASURABLE...HOWEVER WITH STEEP LAPSE RATES AND NAM/SREF
SHOWING LIGHT QPF I ADDED SLIGHT CHANCE POPS TO WESTERN KIT
CARSON/CHEYENNE COUNTIES IN COLORADO IN THE 21-00Z TIME FRAME.

OTHER CONCERN FOR THURSDAY AFTERNOON WILL BE WINDY CONDITIONS WITH
TIGHT UNIDIRECTIONAL GRADIENT OUT OF THE S/SW TO ABOUT H7. THERE
IS SOME SUPPORT OF NEAR ADVISORY CRITERIA DURING THE AFTERNOON
HOURS...HOWEVER DUE TO LOW CONFIDENCE IN DURATION...AND MARGINAL
CONDITIONS I DECIDED AGAINST ISSUANCE.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 115 PM MDT WED APR 24 2013

THURSDAY NIGHT-SATURDAY...UPPER LOW FORECAST TO BE OVER NORTHEAST
ARIZONA AROUND 00Z FRIDAY EXPECTED TO MOVE EAST/NORTHEAST INTO
SOUTHEAST COLORADO BY 12Z FRIDAY THEN SOUTHEAST KANSAS BY 06Z
SATURDAY AND EASTERN ILLINOIS AT 00Z SUNDAY. SHOWERS AND A FEW
THUNDERSTORMS ARE POSSIBLE AS THIS SYSTEM MOVES ACROSS OUR PART OF
THE COUNTRY THURSDAY NIGHT...OTHERWISE DRY THROUGH THE PERIOD.

SATURDAY NIGHT-MONDAY...DRY WITH LITTLE IN THE WAY OF CLOUDINESS.
ABOVE NORMAL TEMPERATURES WITH LOWS IN THE 40S SATURDAY NIGHT
WARMING INTO THE LOW 40S WEST TO LOW 50S EAST SUNDAY NIGHT. HIGHS
SUNDAY MID 70S TO AROUND 80 WEST...LOW 80S EAST. A TAD COOLER MONDAY
WITH MID 70S TO AROUND 80 ACROSS THE AREA...COOLEST WEST. PAST 5
DAYS OF 850 TEMPERATURES WOULD SUPPORT SLIGHTLY WARMER READINGS THEN
CURRENTLY ADVERTISED.

MONDAY NIGHT-WEDNESDAY...PRECIPITATION CHANCES INCREASE A BIT AS AN
UPPER TROUGH AND COLD FRONT MOVE ACROSS THE AREA. HIGH TEMPERATURES
TUESDAY UPPER 60S TO LOW 70S WITH 55-60 WEDNESDAY. LOWS MONDAY NIGHT
MID 40S TO MID 50S (WEST TO EAST)...LOW TO MID 40S (WEST TO EAST)
TUESDAY NIGHT. MAY SEE SOME BREEZY NORTH TO NORTHEAST WINDS
TUESDAY NIGHT THROUGH WEDNESDAY.

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 530 PM MDT WED APR 24 2013

VFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. THE WEST TO NORTHWEST
WINDS WILL DECLINE OVER THE NEXT HOUR OR SO THEN BECOME LIGHT
THROUGH THE NIGHT. THURSDAY A LOW LEVEL JET WILL DEVELOP OVER THE
AREA...WITH GUSTS MIXING DOWN TO THE SURFACE BY MID TO LATE
MORNING. THE GUSTS WILL PEAK BY MID AFTERNOON THEN DECLINE DURING
THE LATE AFTERNOON AS MIXING DISSIPATES WITH THE COOLER TEMPERATURES.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

UPDATE...JTL
SHORT TERM...DR
LONG TERM...99
AVIATION...JTL

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

220 PM CDT TUE APR 23 2013

...UPDATE TO LONG TERM...

.SYNOPSIS...
ISSUED AT 1210 AM CDT TUE APR 23 2013

AT 00Z TUESDAY A -30C TO -32C 500MB TROUGH EXTENDED FROM NORTH
DAKOTA INTO WESTERN WYOMING/EASTERN IDAHO. A +100KT 300MB JET WAS
LOCATED JUST SOUTH OF THIS UPPER TROUGH AND STRETCHED FROM
NORTHERN UTAH INTO NORTHWEST KANSAS. A 700MB TROUGH/BAROCLINIC
ZONE WAS LOCATED FROM SOUTHEAST COLORADO INTO SOUTH CENTRAL
NEBRASKA. AT 00Z TUESDAY AN 850MB COLD FRONT APPEARS TO EXTEND
FROM THE OKLAHOMA PANHANDLE INTO SOUTH CENTRAL KANSAS AND THEN
NORTHEAST INTO SOUTHWEST IOWA. 850MB AND 700MB DEWPOINTS THIS
MORNING INDICATING THE BETTER MOISTURE WAS LOCATED JUST NORTH OF
THIS 850MB FRONT AND SOUTHEAST OF THE 700MB BAROCLINIC ZONE/TROUGH
ACROSS SOUTHERN KANSAS.

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 203 AM CDT TUE APR 23 2013

STEADY SNOW CONTINUES TO FALL ACROSS NORTHWEST KANSAS EARLY AS OF
07Z. THIS RELATED WELL WITH THE MID LEVEL BAROCLINIC ZONE THAT
THE RAP KEEPS NEARLY STATIONARY THROUGH 09Z. THIS BAROCLINIC ZONE
WILL THEN BEGIN TO SLOWLY MOVE SOUTHEAST ACROSS NORTH CENTRAL
KANSAS FROM 09Z TO 15Z AND WILL THEREFORE KEEP CATEGORICAL
PRECIPITATION CHANCES GOING THROUGH LATE MORNING. SNOW
ACCUMULATIONS OF 2 TO NEAR 4 INCHES STILL POSSIBLE BEFORE THE
STEADIER SNOW TAPERS OFF. FURTHER SOUTH ISENTROPIC LIFT AND A
WEDGE OF WARMER AIR IN THE 850-700MB LEVEL WILL RESULT IN A WINTRY
MIX OF FREEZING RAIN, SLEET AND SNOW EARLY THIS MORNING. LATEST
I295 ISENTROPIC SURFACE DOES INDICATE THAT THIS ISENTROPIC LIFT
WILL GIVE WAY TO ISENTROPIC DOWNGLIDE AFTER 12Z SO THE WIDESPREAD
STEADY PRECIPITATION THAT WAS OCCURRING HERE EARLIER THIS MORNING
IN THIS AREA IS EXPECTED TO BECOME MORE WIDELY SCATTERED AND
LIGHTER.

BY THE EARLY AFTERNOON AN AREA OF HIGH PRESSURE AT THE SURFACE
WILL BEGIN TO BUILD INTO WESTERN KANSAS. THERE WILL BE A SLIGHT
CHANCE FOR SOME LIGHT SNOW AHEAD OF AN APPROACHING UPPER LEVEL
TROUGH, HOWEVER LITTLE OR NO ADDITIONAL ACCUMULATION IS EXPECTED.
MODEL SOUNDINGS FOR TODAY INDICATED A DEEP LAYER OF LOW LEVEL
MOISTURE WILL BE PRESENT SO CLOUDY CONDITIONS ARE EXPECTED. GIVEN
THE EXPECTED CLOUD COVER ALONG WITH THE COLD AIR ADVECTION TODAY
IN THE LOWER LEVELS WILL UNDERCUT ALL GUIDANCE FOR HIGHS. THE
PREVIOUS FORECAST STILL LOOKS ON TRACK WITH TEMPERATURES TODAY
MAINLY IN THE LOW TO MID 30S.

SUBSIDENCE DEVELOPING IN THE WAKE OF AN UPPER LEVEL TROUGH WHICH
WILL MOVE EAST OF WESTERN KANSAS EARLY TONIGHT SHOULD ALLOW
CLEARING SKIES TO DEVELOP. AT THE SURFACE AN AREA OF HIGH PRESSURE
WILL CROSS THE CENTRAL HIGH PLAINS DURING THE OVERNIGHT HOURS.
GIVEN CLEARING SKIES, A WEST/NORTHWEST WIND AT LESS THAN 10MPH,
AND SOME SNOW COVER NORTH OF HIGHWAY 50 HAVE DECIDED TO TREND
TOWARDS THE COLDER MET GUIDANCE FOR OVERNIGHT LOWS. TEMPERATURES
BY WEDNESDAY MORNING ARE EXPECTED TO RANGE FROM AROUND 20 TO NEAR
24 DEGREES. THIS CONTINUES TO SUPPORT THE HARD FREEZE WARNING
CURRENTLY IN EFFECT.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 220 PM CDT TUE APR 23 2013

MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL TROUGH PUSHING ASHORE
INTO THE DESERT SOUTHWEST THURSDAY, THEN LIFTING NORTHEAST ACROSS
THE SOUTHERN ROCKIES THURSDAY NIGHT BRINGING THE POSSIBILITY FOR
SHOWERS AND THUNDERSTORMS TO CENTRAL AND PORTIONS OF WESTERN KANSAS
LATE THURSDAY NIGHT INTO FRIDAY. AS THE UPPER LEVEL SHORTWAVE LIFTS
INTO THE SOUTHERN ROCKIES, SURFACE HIGH PRESSURE IS EXPECTED TO
SHIFT FROM THE CENTRAL PLAINS EASTWARD INTO THE MISSISSIPPI RIVER
VALLEY HELPING SET UP A RETURN FLOW ACROSS THE WESTERN HIGH PLAINS
OF KANSAS. MODEST LOW LEVEL MOISTURE WILL ADVECT BACK INTO WESTERN
KANSAS WITH H85 DEWPOINTS IN EXCESS OF 5C NUDGING NORTHWARD INTO
SOUTH CENTRAL AND SOUTHWEST KANSAS. ADDITIONALLY, SURFACE TROUGHING
IS PROJECTED TO DEVELOP ACROSS EASTERN COLORADO LATE THURSDAY, THEN
ADVANCE INTO WESTERN KANSAS AS THE UPPER LEVEL SHORTWAVE EJECTS OUT
OF THE ROCKIES EARLY FRIDAY. ALONG WITH SOME UPSLOPING, THIS WILL
PROVIDE INCREASED LIFT IN THE LOWER LEVELS. ALTHOUGH INSTABILITY
WILL BE SLOW TO INCREASE, DYNAMIC SUPPORT ALOFT WILL BE FAVORABLE
ENOUGH TO SUPPORT SHOWER AND THUNDERSTORM DEVELOPMENT FROM THE
SOUTH PLAINS NORTHWARD INTO PORTIONS OF CENTRAL AND WESTERN KANSAS.
HOWEVER, WIDESPREAD SEVERE WEATHER IS NOT EXPECTED DUE TO A LACK
OF INSTABILITY AS INDICATED BY GFS/ECMWF MODEL SOUNDINGS. DRIER
CONDITIONS ARE LIKELY THROUGH THE WEEKEND AS A MORE ZONAL FLOW
ALOFT SETS UP ACROSS THE WESTERN HIGH PLAINS.

TEMPERATURES WILL REMAIN BELOW NORMAL THURSDAY EVEN AS A GRADUAL
WARMING TREND BEGINS EARLY IN THE PERIOD. AS MENTIONED BEFORE,
SURFACE HIGH PRESSURE IS PROJECTED TO DRIFT EAST OUT OF EASTERN
KANSAS INTO THE MISSISSIPPI RIVER VALLEY RETURNING A LOW LEVEL
SOUTHERLY FLOW TO WESTERN KANSAS. THIS WILL DRAW WARMER AIR
NORTHWARD INTO THE AREA WITH H85 TEMPERATURES RANGING FROM JUST
ABOVE 5C ACROSS CENTRAL KANSAS TO NEAR 15C ALONG THE COLORADO
BORDER. LOOK FOR HIGHS WELL UP INTO THE 60S(F) IN CENTRAL KANSAS TO
NEAR 70F IN EXTREME WESTERN KANSAS THURSDAY AFTERNOON. THE WARMING
TREND WILL CONTINUE INTO THE WEEKEND AS THE FLOW ALOFT BECOMES MORE
ZONAL. HIGHS IN THE 70S(F) ARE EXPECTED BY THIS WEEKEND WITH THE
LOWER TO MID 80S(F) NOT OUT OF THE QUESTION.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1157 AM CDT TUE APR 23 2013

BOTH THE GCK AND HYS TAF SITES WILL START OUT WITH MVFR CIGS IN
THE OVC050 RANGE. LOWER CLOUDS ARE STILL PERSISTING AT THE DDC
SITE, DOWN AT THE BKN015 LEVEL. THERE IS A SLIGHT CHANCE FOR CIGS
IN THE BKN-OVC015 RANGE TO FORM AT THE HYS AND GCK SITES, BUT JUST
WENT WITH A TEMPO GROUP AT BOTH OF THOSE SITES. THE LOW LEVEL FLOW
FROM THE NORTH IS BRINGING SOME LOW LEVEL MOISTURE ACROSS WESTERN
KANSAS. BUT, AT THE SAME TIME, HIGH PRESSURE IS BUILDING IN FROM
COLORADO. EXPECT ALL THREE TAF SITES TO BE IN VFR CONDITIONS BY
03Z TONIGHT. WINDS WILL ALSO SIGNIFICANTLY DROP TO THE NORTHWEST
AT 7 OR 8 KNOTS AFTER SUNSET. BY MIDNIGHT OR SO, CLOUDS WILL
DISSIPATE.

.PRELIMINARY POINT TEMPS/POPS...
DDC 21 57 34 68 / 10 0 0 0
GCK 18 57 33 69 / 0 0 0 0
EHA 24 59 37 69 / 10 0 0 0
LBL 24 59 36 70 / 10 0 0 0
HYS 17 51 31 66 / 10 0 0 0
P28 23 57 36 66 / 10 0 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING FROM 7 PM CDT /6 PM MDT/ THIS EVENING TO 8
AM CDT /7 AM MDT/ WEDNESDAY FOR KSZ030-031-043>046-061>066-
074>081-084>090.

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURKE

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1205 PM CDT TUE APR 23 2013

...UPDATED FOR THE 18Z TAFS AND AVIATION SECTION...

.SYNOPSIS...
ISSUED AT 1210 AM CDT TUE APR 23 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 203 AM CDT TUE APR 23 2013

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 243 AM CDT TUE APR 23 2013

AN UPPER LEVEL SHORTWAVE WILL BE MOVING ACROSS THE NORTHERN PLAINS
AND WESTERN GREAT LAKES REGION ON WEDNESDAY WITH AN 100+ KNOT 250 MB
JET EXTENDING FROM EASTERN COLORADO TO THE OHIO VALLEY. THIS WILL
PLACE WESTERN KANSAS IN A WEST TO NORTHWEST FLOW ALOFT. TOWARDS THE
SURFACE, A DOME OF HIGH PRESSURE WILL CONTINUE TO SLIDE SOUTHEAST
INTO THE SOUTHERN PLAINS ALLOWING WESTERLY WINDS TO BE FELT DURING
THE DAY THEN BECOME LIGHT AND VARIABLE WEDNESDAY NIGHT. SKIES
THROUGH THIS PERIOD WILL GENERALLY BE PARTLY CLOUDY WITH HIGHS IN
THE MID TO UPPER 50S WEDNESDAY AFTERNOON AND LOWS IN THE 30S
THURSDAY MORNING.

ANOTHER UPPER LEVEL SHORTWAVE IS THEN ANTICIPATED TO MOVE INTO THE
DESERT SOUTHWEST THURSDAY THEN LIFT NORTHEAST INTO THE SOUTHERN
ROCKIES THURSDAY NIGHT. HIGH CLOUDS WILL INCREASE IN COVERAGE AS
THIS FEATURE APPROACHES WITH LEE SIDE TROUGHING DEVELOPING ACROSS
EASTERN COLORADO. THIS WILL ALLOW WINDS TO SHIFT TO MORE OF A
SOUTHERLY DIRECTION AND BECOME BREEZY THURSDAY INTO THURSDAY NIGHT.
LOW TO MID LEVEL CLOUDS INCREASE IN COVERAGE THURSDAY NIGHT INTO
FRIDAY WITH THE POSSIBILITY FOR SHOWERS AND THUNDERSTORMS TO DEVELOP
ACROSS PORTIONS OF WESTERN KANSAS. HIGHS THURSDAY WILL GENERALLY BE
IN THE 60S WITH LOWS IN THE 40S FRIDAY MORNING. HIGHS FRIDAY WILL
GENERALLY BE IN THE LOWER 70S.

CLOUDS DECREASE IN COVERAGE FRIDAY NIGHT WITH PARTLY CLOUDY
SKIES AND DRY CONDITIONS ANTICIPATED INTO THE WEEKEND. MEDIUM RANGE
MODELS THEN SUGGEST ANOTHER UPPER LEVEL DISTURBANCE TO POSSIBLY MOVE
NORTH OF THE AREA DURING THE BEGINNING OF NEXT WEEK. THIS COULD
BRING A CHANCE FOR THUNDERSTORMS TO WESTERN KANSAS SUNDAY NIGHT INTO
MONDAY. OTHERWISE EXPECT PARTLY CLOUDY SKIES. THIS WEEKEND LOOK TO BE
IN THE 70S WITH LOWER 80S POSSIBLE ACROSS FAR SOUTHWESTERN KANSAS.
LOWS LOOK TO DIP INTO THE 40S SATURDAY MORNING WITH 50S FORECASTED
FOR SUNDAY AND MONDAY MORNINGS.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1157 AM CDT TUE APR 23 2013

.PRELIMINARY POINT TEMPS/POPS...
DDC 32 22 58 34 / 50 10 0 0
GCK 31 20 58 33 / 80 0 0 0
EHA 35 24 60 37 / 30 10 0 0
LBL 35 24 60 36 / 30 10 0 0
HYS 32 19 55 31 / 80 10 0 0
P28 36 23 58 36 / 60 10 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING FROM 7 PM CDT /6 PM MDT/ THIS EVENING TO 8
AM CDT /7 AM MDT/ WEDNESDAY FOR KSZ030-031-043>046-061>066-
074>081-084>090.

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURKE

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

645 AM CDT TUE APR 23 2013

...UPDATED AVIATION SECTION...

.SYNOPSIS...
ISSUED AT 1210 AM CDT TUE APR 23 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 203 AM CDT TUE APR 23 2013

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 243 AM CDT TUE APR 23 2013

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 642 AM CDT TUE APR 23 2013

LIGHT SNOW WILL CONTINUE THIS MORNING WITH MVFR TO IFR CONDITIONS
ACROSS THE TAF SITES. VISIBILITIES AND CEILINGS SHOULD INCREASE TO
VFR BY THIS AFTERNOON WITH HYS BEING THE ONLY TERMINAL WHERE
ADDITIONAL SNOW MAY BE OBSERVED. WINDS WILL GENERALLY BE FROM THE
NORTH AROUND 20 KNOTS GUSTING TO AROUND 30 KNOTS AT TIMES.

.PRELIMINARY POINT TEMPS/POPS...
DDC 32 22 58 34 / 50 10 0 0
GCK 31 20 58 33 / 80 0 0 0
EHA 35 24 60 37 / 30 10 0 0
LBL 35 24 60 36 / 30 10 0 0
HYS 32 19 55 31 / 80 10 0 0
P28 36 23 58 36 / 60 10 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING UNTIL 8 AM CDT /7 AM MDT/ WEDNESDAY FOR
KSZ030-031-043>046-061>066-074>081-084>090.

WINTER WEATHER ADVISORY UNTIL 10 AM CDT /9 AM MDT/ THIS MORNING
FOR KSZ030-031-043>046-061>066-077>079.

WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR KSZ074>076-080-
081-084>090.

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...HOVORKA_42

AREA FORECAST DISCUSSION

NWS GOODLAND KS

237 AM MDT TUE APR 23 2013

.UPDATE...
ISSUED AT 1109 PM MDT MON APR 22 2013

MODERATE TO HEAVY SNOW CONTINUES TO FALL AROUND THE GLD
AREA...WITH ANOTHER BAND DEVELOPING SOUTH OF YUMA TRACKING ALONG
SIMILAR PATH AS OTHER SNOW BANDS. SNOWFALL AMOUNTS HAVE VARIED
QUITE A BIT...WITH GLD AT 5 INCHES AND ST FRANCIS ONLY REPORTING A
HALF OF AN INCH SO FAR. WITH MUCAPE FIELDS SUPPORTING INSTABILITY
AXIS ALONG AN IDALIA TO RUSSEL SPRINGS LINE FOR THE NEXT FEW HOURS
BEFORE SHIFTING EAST AND STRONG FRONTOGENESIS ALSO FALLING A
SIMILAR PATTERN...THINK HEAVIER SNOW OBSERVED AT GLD WILL CONTINUE
TO MOVE EAST SOUTH EAST. WITH GLD ALREADY NEAR WARNING CRITERIA
AND DUE TO AFOREMENTIONED REASONS HAVE UPGRADED PART OF ADVISORY
TO A WARNING FOR THE REST OF THE NIGHT. CONSIDERED ADDING YUMA AND
CHEYENNE COUNTY KS TO WARNING AS SOUTHERN PART OF COUNTY WILL
LIKELY SEE 6 TO 8 INCHES...BUT STRONG NORTH-SOUTH SNOWFALL
GRADIENT WILL KEEP MUCH OF THESE AREAS BELOW WARNING CRITERIA.
MUCAPE AXIS EVENTUALLY MOVES INTO THE EASTERN CWA CENTERED AROUND
HLC HAVE CONCERNS HEAVY SNOW MAY MAKE IT THIS FAR EAST AS
WELL...BUT NEED TO MONITOR HOW PRECIP FIELDS BEHAVE A BIT LONGER
BEFORE MAKING THAT CALL.

UPDATE ISSUED AT 817 PM MDT MON APR 22 2013

01Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED TROUGH DIGGING INTO
NORTHERN UTAH AND NORTHWEST COLORADO WITH 100KT+ H3 JET STREAK
EXTENDING AHEAD OF THE TROUGH AND ACROSS CWA. 00Z RAOBS INDICATE
DEEP COLD AIR MASS EXTENDING AS HIGH AS 675MB AT DNR. AT THE
SFC...1032 MB SFC HIGH WAS BUILDING INTO THE REGION WITH COLD FRONT
AS FAR SOUTH AS THE TEXAS PANHANDLE.

WITH WINDS GRADUALLY DECREASING MAIN CONCERN WILL CENTER AROUND
SNOWFALL AMOUNTS THROUGH THE NIGHT. AM A LITTLE CONCERNED THAT BOTH
NAM AND RAP SUPPORT A PERIOD OF ELEVATED INSTABILITY NEAR GLD
THROUGH 7Z WITH MUCAPES AROUND 100 J/KG BRINGING THE POTENTIAL FOR
ENHANCED SNOWFALL RATES IN THIS AREA.

COMPOSITE REFLECTIVITY/SNOW OBSERVATIONS INDICATING MODERATE TO
HEAVY SNOW HAS BEEN OCCURRING WITH FAIRLY WIDESPREAD 2-3 INCHES
ALREADY OBSERVED FROM JUST EAST OF FLAGLER TO GOODLAND AND WITH
INSTABILITY PROFILES AND STRONG H65 FRONTOGENESIS ACROSS THIS AREA
THROUGH 6Z THINK HEAVIER PRECIPITATION WILL CONTINUE FROM A JOES TO
RUSSEL SPRINGS LINE...WITH MUCH LOWER AMOUNTS EXPECTED TO THE
SOUTHWEST OF THAT AREA. GIVEN POTENTIAL FOR ELEVATED CONVECTION...AM
CONCERNED THAT SOME LOCATIONS MAY GET TO THE 6-8 INCH RANGE BUT WITH
CONVECTIVE NATURE OF PRECIP AND FORCING GRADUALLY TRANSITIONING TO
THE SOUTH EAST...CONFIDENCE NOT QUITE HIGH ENOUGH FOR AN UPGRADE TO
A WARNING AT THIS POINT.

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 223 PM MDT MON APR 22 2013

A NEGATIVELY TILTED LONGWAVE H5 TROUGH WAS DIGGING ACROSS THE
WESTERN CONUS TODAY AND WILL MOVE THROUGH THE CENTRAL US TONIGHT
INTO TOMORROW. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM HAS
ALREADY MOVED THROUGH THE ENTIRE CWA BRINGING GUSTY NORTHERLY WINDS
AND COOLER TEMPS.

PRECIP SHOULD BEGIN AS SNOW AS TEMPS DECREASE RAPIDLY LATE THIS
AFTERNOON ACROSS THE REGION. MOST GUIDANCE WAS FAIRLY AGGRESSIVE
WITH QPF/SNOW AMOUNTS BUT GIVEN THE SATURATED COLUMN DID NOT GO TOO
MUCH LOWER WITH THE FORECAST...AMOUNTING TO A TOTAL OF 1 TO 3 INCHES
ACROSS THE CWA. BEST CHANCE FOR PRECIP LOOKS TO BE SOUTH OF I-70.
THINK LIGHT SNOW SHOWERS IN FAR SOUTH COUNTIES ARE NOT OUT OF THE
QUESTION TOMORROW AS TROUGH AXIS EXITS THE REGION...BUT MOST OF THE
SNOWFALL WILL OCCUR TONIGHT. TEMPS WILL REACH NEAR-RECORD LOWS
TONIGHT AND WILL STRUGGLE TO REACH THE UPPER 30S TOMORROW AFTERNOON.
WIND CHILLS TONIGHT WILL BE IN THE SINGLE DIGITS...QUITE FRIGID FOR
LATE APRIL.

.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 236 AM MDT TUE APR 23 2013

AN UPPER LEVEL SHORTWAVE WILL TRAVERSE THE AREA AT THE START OF THE
EXTENDED PERIOD. HAVE POPS RANGING FROM SLIGHT CHANCE MIDDLE FA TO
LOW CHANCE EAST ON FRIDAY. MODELS INDICATE BEST LOW LEVEL MOISTURE
TO BE OVER THE EASTERN PORTION OF THE CWA...HENCE HIGHER POPS THERE.
INCLUDED THUNDER GIVEN THAT MODEL FORECAST SOUNDINGS INDICATE AT
LEAST WEAK INSTABILITY. UPPER LEVEL RIDGING BUILDS INTO THE AREA
THIS WEEKEND AND TEMPERATURES WARM TO ABOVE NORMAL. ECMWF IS SLOWER
THAT THE GFS IN SHIFTING THE UPPER LEVEL RIDGE EASTWARD. HAVE
ACCEPTED CR INIT GRIDS FOR MONDAY WHICH SEEM TO BE WEIGHTED TO THE
GFS AND INCLUDE SLIGHT CHANCE POP. GIVEN DISAGREEMENT BETWEEN MODELS
CONFIDENCE IS LOW ON MONDAY AND ADJUSTMENTS WILL LIKELY BE NEEDED IN
LATER FORECASTS.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1134 PM MDT MON APR 22 2013

PERIOD OF MFVR OR LOWER FLIGHT CONDITIONS EXPECTED AT BOTH
TERMINALS THE REST OF THE NIGHT WITH THE HIGHEST IMPACT/LOWEST
FLIGHT CATEGORIES EXPECTED AT GLD AS AREA OF MODERATE TO HEAVY
SNOW WILL CONTINUE TO MOVE ACROSS THE AREA THROUGH 10Z. WINDS
WILL GRADUALLY WEAKEN THROUGH THE EVENING...ALTHOUGH WILL REMAIN
IN THE 15-22KT RANGE FOR MUCH OF THE PERIOD...BEFORE DECREASING
LATE THIS AFTERNOON. MCCOOK FOR THE MOST PART WILL REMAIN TO THE
NORTH OF HEAVIEST SNOWFALL AND EXPECT REDUCE FLIGHT CATEGORIES TO
BE MORE TRANSIENT IN THIS AREA.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 9 AM MDT /10 AM CDT/ THIS MORNING
FOR KSZ001>004-015-016-041-042.

WINTER STORM WARNING UNTIL 9 AM MDT /10 AM CDT/ THIS MORNING FOR
KSZ013-014-027>029.

CO...WINTER WEATHER ADVISORY UNTIL 9 AM MDT THIS MORNING FOR COZ090-
092.

WINTER STORM WARNING UNTIL 9 AM MDT THIS MORNING FOR COZ091.

NE...NONE.
&&

UPDATE...JRM
SHORT TERM...JJM
LONG TERM...FS/BRB
AVIATION...JRM

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

244 AM CDT TUE APR 23 2013

...UPDATED LONG TERM SECTION...

.SYNOPSIS...
ISSUED AT 1210 AM CDT TUE APR 23 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 203 AM CDT TUE APR 23 2013

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 243 AM CDT TUE APR 23 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1210 AM CDT TUE APR 23 2013

GUSTY NORTH WINDS AT AROUND 25KTS WILL GRADUALLY DECREASE AFTER
15Z TUESDAY AS A RIDGE OF HIGH PRESSURE AT THE SURFACE BEGINS
BUILD INTO WESTERN KANSAS. WIND SPEEDS OF AROUND 20KTS ARE
EXPECTED BY 15Z. BUFR SOUNDINGS KEEP THE LOWER LEVELS SATURATED
THROUGHOUT THE EARLY MORNING HOURS SO CIGS ARE EXPECTED TO STAY
AS IS OR FALL A FEW HUNDRED FEET INTO THE IFR/LOW MVFR CATEGORY
EARLY THIS MORNING. CIGS WILL BEGIN TO IMPROVE AS PRECIPITATION
ENDS AFTER 12Z. CLEARING SKIES DEVELOPING FROM WEST TO EAST AFTER
00Z WEDNESDAY. WINTRY MIX OF PRECIPITATION IS EXPECTED OVERNIGHT
BUT AFTER 15Z THE BETTER LIFT APPEARS TO START TO SHIFT EAST.

.PRELIMINARY POINT TEMPS/POPS...
DDC 32 22 58 34 / 50 10 0 0
GCK 31 20 58 33 / 80 0 0 0
EHA 35 24 60 37 / 30 10 0 0
LBL 35 24 60 36 / 30 10 0 0
HYS 32 19 55 31 / 80 10 0 0
P28 36 23 58 36 / 60 10 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING UNTIL 8 AM CDT /7 AM MDT/ WEDNESDAY FOR
KSZ030-031-043>046-061>066-074>081-084>090.

WINTER WEATHER ADVISORY UNTIL 10 AM CDT /9 AM MDT/ THIS MORNING
FOR KSZ030-031-043>046-061>066-077>079.

WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR KSZ074>076-080-
081-084>090.

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURGERT

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

210 AM CDT TUE APR 23 2013

...UPDATED SHORT TERM DISCUSSION...

.SYNOPSIS...
ISSUED AT 1210 AM CDT TUE APR 23 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 203 AM CDT TUE APR 23 2013

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 110 PM CDT MON APR 22 2013

MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH
SWINGING SOUTHEAST ACROSS THE NORTHERN PLAINS WEDNESDAY AND INTO THE
GREAT LAKES REGION WEDNESDAY NIGHT. ALTHOUGH AN ATTENDANT COLD FRONT
IS PROJECTED TO PUSH SOUTH JUST INTO WESTERN KANSAS LATE WEDNESDAY
BEFORE IT STALLS, LITTLE PRECIP IS EXPECTED ACROSS THE REGION WITH
LITTLE MOISTURE FOR THE SYSTEM TO WORK WITH. MEANWHILE, AN UPPER
LEVEL TROUGH NOW APPROACHING THE COAST OF SOUTHERN CALIFORNIA, WILL
PUSH ASHORE INTO THE DESERT SOUTHWEST THURSDAY THEN LIFT NORTHEAST
INTO THE SOUTHERN ROCKIES THURSDAY NIGHT BRINGING THE POSSIBILITY
FOR SHOWERS AND THUNDERSTORMS TO PORTIONS OF WESTERN KANSAS LATE
THIS WEEK. TIMING REMAINS AN ISSUE AS IT PERTAINS TO THE ARRIVAL OF
THE SYSTEM COMBINED WITH MOISTURE AVAILABILITY. REGARDLESS, THE
BETTER CHANCE FOR PRECIP LOOKS TO BE DURING THE THURSDAY NIGHT INTO
FRIDAY TIME FRAME.

TEMPERATURES WILL BE WELL BELOW NORMAL WEDNESDAY AS A COLD AIR MASS
IS SLOW TO ERODE OUT OF WESTERN KANSAS. SURFACE HIGH PRESSURE IS
PROJECTED TO DRIFT EAST INTO EASTERN KANSAS RESULTING IN FAIRLY
LIGHT AND VARIABLE WIND CONDITIONS ACROSS CENTRAL AND MUCH OF
SOUTHWEST KANSAS ALLOWING THE COLDER AIR TO LINGER. THE NAM, GFS,
AND ECMWF SHOW H85 TEMPERATURES RANGING AROUND TO JUST ABOVE 5C
ACROSS CENTRAL AND SOUTHWEST KANSAS WEDNESDAY AFTERNOON. EVEN WITH
EXPECTED DECREASING CLOUDS, LOOK FOR HIGHS GENERALLY UP INTO THE
50S(F) WITH A FEW 40S(F) STILL POSSIBLE ACROSS CENTRAL KANSAS. FOR
THURSDAY, BROAD SURFACE HIGH PRESSURE ACROSS THE MISSISSIPPI RIVER
VALLEY REGION WILL HELP TO INFLUENCE A LOW LEVEL SOUTHERLY FLOW INTO
WESTERN KANSAS. THIS WILL DRAW WARMER AIR NORTHWARD INTO THE AREA
WITH H85 TEMPERATURES JUST ABOVE 5C ACROSS CENTRAL KANSAS TO NEAR
15C IN FAR WESTERN KANSAS ALONG THE COLORADO BORDER. SHOULD SEE
60S(F) IN CENTRAL KANSAS TO NEAR 70F IN EXTREME WESTERN KANSAS FOR
HIGHS THURSDAY AFTERNOON. THE WARMING TREND WILL CONTINUE INTO THE
WEEKEND AS THE FLOW ALOFT BECOMES MORE ZONAL.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1210 AM CDT TUE APR 23 2013

.PRELIMINARY POINT TEMPS/POPS...
DDC 32 22 58 34 / 50 10 0 0
GCK 31 20 58 33 / 80 0 0 0
EHA 35 24 60 37 / 30 10 0 0
LBL 35 24 60 36 / 30 10 0 0
HYS 32 19 55 31 / 80 10 0 0
P28 36 23 58 36 / 60 10 0 0

.DDC WATCHES/WARNINGS/ADVISORIES...
HARD FREEZE WARNING UNTIL 8 AM CDT /7 AM MDT/ WEDNESDAY FOR
KSZ030-031-043>046-061>066-074>081-084>090.

WINTER WEATHER ADVISORY UNTIL 10 AM CDT /9 AM MDT/ THIS MORNING
FOR KSZ030-031-043>046-061>066-077>079.

WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR KSZ074>076-080-
081-084>090.

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1137 PM MDT MON APR 22 2013

.UPDATE...
ISSUED AT 1109 PM MDT MON APR 22 2013

UPDATE ISSUED AT 817 PM MDT MON APR 22 2013

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 223 PM MDT MON APR 22 2013

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 223 PM MDT MON APR 22 2013

RELATIVELY QUIET WEATHER WILL SET IN FOR THE TRI-STATE AREA
THROUGHOUT THE EXTENDED FORECAST. A WARMING TREND IS ALSO
EXPECTED...WITH A RETURN TO NEAR AND ABOVE NORMAL TEMPERATURES
FORECAST BY THURSDAY. ABOVE NORMAL TEMPERATURES ARE LIKELY THROUGH
THE WEEKEND AND INTO THE BEGINNING OF NEXT WEEK.

AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE PLAINS ON WEDNESDAY.
MODELS HAVE TRENDED FURTHER NORTH WITH THIS SYSTEM SO HAVE CONTINUED
A DRY FORECAST. NORTHWEST WINDS SHOULD PICK UP AHEAD THE DISTURBANCE
ON WEDNESDAY AFTERNOON. HIGH TEMPERATURES ON WEDNESDAY SHOULD CLIMB
INTO THE MID 50S.

THE NEXT UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THURSDAY NIGHT
AND INTO FRIDAY. WITH WARMER TEMPERATURES...SOME INSTABILITY
FORECAST BY MODELS AS WELL AS DECENT LAPSE RATES AND A POSSIBLE
DRYLINE IN THE AREA...THERE COULD BE A CHANCE FOR SOME
THUNDERSTORMS. MODELS PROJECT THE SHORTWAVE WILL PASS THROUGH DURING
THE OVERNIGHT HOURS THURSDAY...WHICH WOULD LIMIT THE CHANCES FOR
STRONG TO SEVERE THUNDERSTORMS. IF THE SHORTWAVE SLOWS DOWN AND PASS
THROUGH LATER IN THE DAY ON FRIDAY...THERE WILL BE A BETTER CHANCE FOR
SOME STRONG THUNDERSTORMS.

THE COMING WEEKEND LOOKS VERY NICE WITH LITTLE CHANCE OF
PRECIPITATION AND TEMPERATURES IN THE 70S...NEARING OR EXCEEDING 80
IN SOME LOCATIONS. WITH DRIER AIR TO THE WEST...FIRE WEATHER COULD
BECOME A CONCERN BUT WINDS ARE PROJECTED TO BE FAIRLY LIGHT AT THE
PRESENT TIME.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1134 PM MDT MON APR 22 2013

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 9 AM MDT /10 AM CDT/ TUESDAY FOR
KSZ001>004-015-016-041-042.

WINTER STORM WARNING UNTIL 9 AM MDT /10 AM CDT/ TUESDAY FOR
KSZ013-014-027>029.

CO...WINTER WEATHER ADVISORY UNTIL 9 AM MDT TUESDAY FOR COZ090-092.

WINTER STORM WARNING UNTIL 9 AM MDT TUESDAY FOR COZ091.

NE...NONE.
&&

UPDATE...JRM
SHORT TERM...JJM
LONG TERM...RRH
AVIATION...JRM

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1119 PM MDT MON APR 22 2013

.UPDATE...
ISSUED AT 1109 PM MDT MON APR 22 2013

UPDATE ISSUED AT 817 PM MDT MON APR 22 2013

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 223 PM MDT MON APR 22 2013

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 223 PM MDT MON APR 22 2013

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 519 PM MDT MON APR 22 2013

PERIOD OF MFVR OR LOWER FLIGHT CONDITIONS EXPECTED AT BOTH
TERMINALS TONIGHT WITH THE HIGHEST IMPACT/LOWEST FLIGHT CATEGORIES
EXPECTED AT GLD AS AREA OF MODERATE TO HEAVY SNOW WILL CONTINUE TO
MOVE ACROSS THE AREA FOR THE NEXT FEW HOURS. LOOKING AT VERTICAL
STABILITY PROFILES...HAVE CONCERN THAT AT LEAST MODERATE SNOW WILL
CONTINUE THROUGH 8Z...BUT WANT TO SEE HOW THINGS DEVELOP THROUGH
THE NEXT FEW HOURS BEFORE COMMITTING TO WIDESPREAD PERSISTENT LIFR
CONDITIONS. WINDS WILL GRADUALLY WEAKEN THROUGH THE
EVENING...ALTHOUGH WILL REMAIN IN THE 15-22KT RANGE FOR MUCH OF
THE PERIOD.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 9 AM MDT /10 AM CDT/ TUESDAY FOR
KSZ001>004-015-016-041-042.

WINTER STORM WARNING UNTIL 9 AM MDT /10 AM CDT/ TUESDAY FOR
KSZ013-014-027>029.

CO...WINTER WEATHER ADVISORY UNTIL 9 AM MDT TUESDAY FOR COZ090-092.

WINTER STORM WARNING UNTIL 9 AM MDT TUESDAY FOR COZ091.

NE...NONE.
&&

UPDATE...JRM
SHORT TERM...JJM
LONG TERM...RRH
AVIATION...JRM

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1003 PM EDT WED APR 24 2013

.UPDATE...
ISSUED AT 1002 PM EDT WED APR 24 2013

LATEST STLT IMAGERY AND RUC ANALYSIS SHOW A PAIR OF SHRTWVS ROTATING
THRU UPR TROF CENTERED FM HUDSON BAY INTO THE GREAT LKS. A BAND OF
SHRASN IS EVIDENT STRETCHING FM THE WRN CWA SWWD THRU NW WI INTO SE
MN RIGHT AHEAD OF THE FIRST DISTURBANCE. A MORE POTENT SHRTWV/70KT
H3 JET MAX ARE DIGGING SSEWD INTO WRN MN RIGHT BEHIND THE FIRST
SHRTWV. AS A RESULT...THE SRN END OF THE PCPN BAND IS TENDING TO
INTENSIFY AND TAKING ON A BOW ECHO APPEARANCE UNDER THE SHARPER
DPVA/H7-3 QVECTOR CNVGC ACCOMPANYING THE MORE POTENT SHRTWV. WIND
GUSTS IN THE WAKE OF THE PASSAGE OF THIS LINE OF SHRA/EMBEDDED TS
REACHED 42 KTS AT ROCHESTER MN. AT THE SAME TIME...CLD TOP TEMPS
OVER THE N END OF THE BAND ARE RISING...AND RADAR ECHOES ARE TENDING
TO DIMINISH OVER WRN UPR MI. THE LATEST RUC/HRRR MODELS APPEAR TO
HAVE THE BEST HANDLE ON THESE TRENDS...SO USED THEIR OUTPUT FOR FCST
UPDATE. THESE MODELS HINT THE MORE SGNFT PCPN...THE REMNANTS OF THE
LINE OF SHRA MOVING INTO WRN WI...WL IMPACT THE SCNTRL CWA AFT 06Z
CLOSER TO THE STRONGER DYNAMICS ASSOCIATED WITH THE SHRTWV FCST TO
DIG INTO THE UPR MIDWEST. SO TENDED TO CUT POPS/QPF/FCST SN AMOUNTS
A BIT OVER THE NW CWA WHILE DOING THE OPPOSITE OVER THE SCNTRL. DID
RETAIN HI LIKELY POPS AND UP TO 2 INCHES OF SN FOR THE NW CLOSER TO
BAND OF SHARPER H85-7 FGEN FCST BY SEVERAL MODELS OVER THIS AREA IN
THE PRESENCE OF FAIRLY UNSTABLE LAPSE RATES.

REMOVED MENTION OF -FZRA FM FCST EARLIER TO REFLECT UNSTABLE LLVL
LAPSE RATES SHOWN ON FCST/OBSVD 00Z RAOBS AND ABSENCE OF ELEVATED
WARM LYR IN FCST SDNGS.
&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 527 PM EDT WED APR 24 2013

A SHORTWAVE UPPER AND ASSOCIATED SFC TROUGH AREA OVER NW MN THIS
AFTERNOON...WITH PRECIP OUT AHEAD OF THE TROUGH MOVING INTO FAR WRN
LAKE SUPERIOR. AS THE SYSTEM MOVES ACROSS THE CWA TONIGHT INTO THU
MORNING...IT WILL DEEPEN AND CLOSE OFF...POSSIBLY LEADING TO AN FGEN
BAND OF SNOW OVER THE KEWEENAW/NW UP TONIGHT ALONG WITH THE REST OF
THE SYNOPTIC PRECIP OVER MUCH OF THE REST OF THE CWA. VERY UNCERTAIN
AS TO THE EXACT TRACK/INTENSITY OF THE THIN FGEN BAND...IF IT
DEVELOPS...SO WILL NOT ISSUE ANY HEADLINES FOR THAT RIGHT NOW...EVEN
THROUGH A NARROW BAND OF ADVISORY LEVEL SNOWFALL OF UP TO 4 INCHES
IS POSSIBLE WITH THE BAND. ELSEWHERE...PRECIP WILL BE MOSTLY
SNOW...EXCEPT OVER THE CENTRAL AND ERN CWA WHERE MORE RAIN AND SOME
FREEZING RAIN WILL BE POSSIBLE. TEMPS WILL NOT BE AS COLD TONIGHT AS
LAST NIGHT DUE TO THE PRECIP AND CLOUD COVER.

THU WILL SEE THE SYSTEM MOVING OUT IN THE MORNING...WITH DECREASING
CLOUDS THROUGHOUT THE DAY. EXPECT HIGHS IN THE 40S TO AROUND
50...COOLER NEAR LAKE SUPERIOR WITH ANY LAKE BREEZES THAT DEVELOP.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 527 PM EDT WED APR 24 2013

SPRING WARMUP LOOKS TO BE JUST AROUND THE CORNER AS A MAJOR PATTERN
CHANGE IS EXPECTED FOR LATE THIS WEEK INTO EARLY NEXT WEEK. THE
CNTRL TO ERN CONUS TROF THAT HAS MAINTAINED THE PERSISTENT COLDER
TEMPS OVER THE UPPER LAKES WILL QUICKLY RETREAT INTO NE CANADA AS
THE RIDGE ALONG THE W COAST BEGINS TO FLATTEN...ALLOWING WARMER
PACIFIC FLOW TO SPREAD ACROSS THE NRN CONUS. BY EARLY NEXT
WEEK...TROF WILL SHIFT INTO THE WRN CONUS...LEADING TO STRONG
RIDGING OVER THE E. THE SW FLOW BTWN THESE FEATURES WILL LEAD TO A
MAJOR WARMUP FOR THE UPPER LAKES AT LEAST FOR THE EARLY PORTION OF
NEXT WEEK. GIVEN THE RECORD DEEP LATE SEASON SPRING SNOWPACK AND
ASSOC HIGH SNOW WATER EQUIVALENTS (GENERALLY 5-11 INCHES) FOR
WESTERN AND NORTHERN PORTIONS OF THE CWA...THE ABOVE NORMAL TEMPS
WILL LEAD TO SIGNIFICANT/PERSISTENT MELTING...AND THE POTENTIAL FOR
FLOODING OF SOME RIVERS AND STREAMS NEXT WEEK. FORTUNATELY...IT
APPEARS THAT RAINFALL SHOULD GENERALLY BE ON THE LIGHT SIDE AT LEAST
THROUGH SUNDAY.

MAJOR PATTERN CHANGE BEGINS FRIDAY AS PACIFIC FLOW BEGINS TO SURGE
ACROSS THE NRN CONUS...FORCING TROFFING TO THE E AND NE. 850MB TEMPS
WILL REBOUND FROM -3/-5C THU EVENING TO 4/6C BY FRI EVENING.
STRONGEST WAA/ISENTROPIC ASCENT MOST EVIDENT ON 290K SFC SWINGS
ACROSS THE UPPER LAKES FRI...AND IT SHOULD BE SUFFICIENT TO GENERATE
SOME AN AREA OF -RA ACROSS MAINLY THE CENTRAL AND ERN FCST AREA.
GIVEN INITIAL DRYNESS OF AIRMASS...ONLY CHC POPS WARRANTED. PCPN MAY
BEGIN LATE THU NIGHT AS -RA/-SN OVER THE FAR W. EVEN WITH
CLOUDS...TEMPS SHOULD STILL BE ABLE TO RISE WELL INTO THE 50S
FRI...PERHAPS EVEN LOWER 60S OVER THE INTERIOR WEST WHERE SOME
AFTERNOON SUNSHINE IS POSSIBLE. HOWEVER...WITH BRISK S WINDS UP LAKE
MICHIGAN...TEMPS WILL BE HELD TO THE 40S OVER THE EAST HALF.

SATURDAY LOOKS DRY AND EVEN WARMER WITH A FAIR AMOUNT OF SUNSHINE.
850MB TEMPS OF 6-8C SHOULD YIELD MAX TEMPS IN THE LOWER TO MID 60S
OVER THE WEST HALF. AGAIN SOUTHERLY WINDS WILL KEEP THE EAST HALF
COOLER...ESPECIALLY NEAR THE SHORELINE AREAS WHERE HIGH TEMPS WILL
STRUGGLE TO REACH THE MID 40S.

AS ERN RIDGING BUILDS EARLY NEXT WEEK...THE UPPER LAKES MAY BE
BRUSHED BY A COUPLE OF SHORTWAVES LIFTING MAINLY W AND N OF THE AREA
SUN/MON. AS FIRST SHORTWAVE MOVES LATE SAT NIGHT INTO SUNDAY...ASSOC
FORCING IS PRETTY WEAK AS EVIDENCED BY Q-VECT CONV SO ONLY SLIGHT
CHC POPS WARRANTED OVER THE WRN COUNTIES LATE SAT NIGHT AND THEN
OVER THE NRN TIER ON SUNDAY. THERE SHOULD A BE A BETTER CHC OF RAIN
SHOWERS LATE SUN NIGHT INTO MONDAY AS SECOND SHORTWAVE LIFTING TO
THE NORTH PUSHES A WEAK COLD FRONT/TROUGH INTO THE AREA. FORCING
WITH THIS SECOND SHORTWAVE COULD BE AIDED BY UPR DIVERGENCE IN RIGHT
ENTRANCE REGION OF 80 KT 3K JET MAX LIFTING NORTH OF LAKE SUPERIOR.
HAVE INCLUDED HIGHER CHC 40-50 PCT POPS FOR RAIN SHOWERS AS FRONTAL
BOUNDARY SLOWLY WORKS ITS WAY ACROSS THE CWA LATE SUN NIGHT INTO
MONDAY. BOTH GFS AND ECMWF SHOW POTENTIAL FOR UP TO QUARTER INCH OF
RAINFALL. MODELS INDICATE FRONTAL BOUNDARY COULD STALL OUT OVER EAST
AND SCNTRL PORTIONS OF CWA LATE MONDAY AND THEN LIFT NORTH AS A WARM
FRONT ON MONDAY NIGHT. WL KEEP CHC POPS IN FOR POSSIBLE SCT SHOWERS
MON NIGHT AS WARM FRONT LIFTS NORTH.

TUESDAY LOOKS MAINLY DRY AND POTENTIALLY QUITE WARM AS 5H RIDGE HGTS
AMPLIFY ACROSS THE UPPER GREAT LAKES. STRONG SRLY FLOW SETS UP OVER
THE AREA AHEAD OF NEXT APPROACHING SHORTWAVE AND ASSOC FRONTAL
SYSTEM OVER THE NRN PLAINS. ECMWF AND GFS SHOWS 8H THERMAL RIDGE
WITH 12C TEMPS OR WARMER MOVING ACROSS THE AREA. DEPENDING ON THE
DEGREE OF CLOUD COVER/SUNSHINE...MAX TEMPS INTO THE 70S ARE
DEFINITELY POSSIBLE OVER THE WRN HALF OF THE CWA. AS THE NEXT
FRONTAL SYSTEM MOVES THROUGH TUE NIGHT INTO WED...PER
GFS/ECMWF...CHC POPS HAVE BEEN INTRODUCED. COULD SEE THE POTENTIAL
FOR HEAVIER RAINFALL WITH THIS SYSTEM AS MODELS HINT THAT THE FRONT
COULD STALL OUT JUST SOUTH AND EAST OF OUR FCST AREA LATE WED INTO
WED NIGHT. SHORTWAVES RIDING ALONG THE FRONT COULD BRING THE
POTENTIAL FOR MORE SIGNIFICANT RAINFALL LATE NEXT WEEK AS DEEPER
GULF MOISTURE COULD WORK ITS WAY INTO THE GREAT LAKES REGION. THIS
RAINFALL POTENTIAL WILL NEED TO BE CLOSELY MONITORED ON FUTURE MODEL
RUNS ESPECIALLY GIVEN INCREASING FLOOD POTENTIAL DUE TO SNOWMELT
RUNOFF.
&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 729 PM EDT WED APR 24 2013

EXPECT A PERIOD OF MVFR CONDITIONS ASSOCIATED WITH AREA OF PCPN...
WHICH WL BE MAINLY IN THE FORM OF SN...ACCOMPANYING INCOMING LO PRES
TROF FM MN TO ARRIVE W-E AT ALL 3 TAFS SITES TNGT. SOME GUIDANCE
INDICATES SOME HEAVIER SHSN WL FALL AND BRING IFR CONDITIONS. THIS
SCENARIO IS MOST LIKELY AT IWD THIS EVNG AND AT CMX IN THE HRS
AROUND 06Z. ALTHOUGH MVFR CIGS ARE LIKELY TO LINGER THRU SUNRISE
EVEN AFTER THE DISTURBANCE PASSES TO THE E AND DRYING ALF DIMINISHES
THE PCPN...THE ONSET OF DAYTIME HEATING WL BRING VFR CONDITIONS BY
THE AFTN.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 527 PM EDT WED APR 24 2013

OTHER THAN AN INCREASE IN SRLY WINDS TO 25 KTS OVER THE ERN HALF OF
LAKE SUPERIOR LATE SUNDAY INTO SUNDAY EVENING AHEAD OF APPROACHING
COLD FRONTAL SYSTEM...WINDS ARE EXPECTED TO STAY AT OR BELOW 20 KTS
THROUGH THE FCST PD.
&&

.HYDROLOGY...
ISSUED AT 527 PM EDT WED APR 24 2013

UPCOMING MAJOR PATTERN CHANGE WILL BRING A DRAMATIC WARMUP TO THE
UPPER GREAT LAKES LATE THIS WEEK THRU THE FIRST HALF OF NEXT WEEK.
TEMPS WILL SWING TO ABOVE/WELL ABOVE NORMAL...BEGINNING FRI WHEN
TEMPS WILL RISE WELL INTO THE 50S WEST HALF...PERHAPS EVEN LOWER
60S. HIGHS WILL REACH WELL INTO THE 60S OVER THE WEEKEND INTO EARLY
NEXT WEEK WITH HIGHS AROUND 70F POSSIBLE SUN-TUE FOR SOME WRN
LOCATIONS. SNOW MELT SHOULD CONTINUE FOR THE NIGHTTIME HRS AS
TEMPERATURES ARE EXPECTED TO STAY ABOVE FREEZING.

THE WARM AIR WILL LEAD TO A SIGNIFICANT MELT OF THE UNUSUALLY DEEP
LATE SPRING SEASON SNOW PACK ACROSS THE SNOWBELTS OF WRN AND NRN
UPPER MI...AND RIVER LEVELS WILL BEGIN RISING EARLY THIS WEEKEND.
BASED ON THE EXISTING SNOW WATER EQUIVALENT...THE MOST SIGNIFICANT
ISSUES ARE EXPECTED OVER THE WESTERN HALF OF UPPER MICHIGAN...WHERE
SOME RIVERS WILL LIKELY REACH FLOOD STAGE. FOR FURTHER DETAILS...SEE
THE HYDROLOGIC OUTLOOK /ESF/.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...KC
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...KC
MARINE...VOSS
HYDROLOGY...VOSS

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

155 PM EDT TUE APR 23 2013

.SYNOPSIS...
ISSUED AT 400 AM EDT TUE APR 23 2013

STEADY RAINS WILL ARRIVE THIS AFTERNOON AND LINGER INTO THIS
EVENING. MOST AREAS WILL SEE BETWEEN A HALF AN INCH AND AN INCH OF
RAIN. THIS SHOULD NOT RESULT IN RISING RIVER LEVELS...BUT IT WILL
DELAY THEIR FALL. COOLER AIR MOVES IN BEHIND THE COLD FRONT THAT
WILL PRODUCE THIS RAIN. DAYTIME TEMPERATURES FOR BOTH WEDNESDAY AND
THURSDAY WILL ONLY BE IN THE 40S. ANOTHER PERIOD OF LIGHTER RAIN IS
EXPECTED WEDNESDAY NIGHT INTO THURSDAY MORNING. THERE SHOULD ALSO
BE SOME SNOW THAT MIXES IN WITH THE RAIN. PORTIONS OF CENTRAL LOWER
MICHIGAN COULD SEE A LIGHT DUSTING OF ACCUMULATION BY THURSDAY
MORNING.

WEATHER CONDITIONS SHOULD IMPROVE FOR THE LATTER PORTION OF THE WEEK
INTO THE WEEKEND. MAINLY DRY CONDITIONS ARE EXPECTED ALONG WITH
WARMING TEMPERATURES. BY SUNDAY AND MONDAY MID TO UPPER 60S SHOULD
BE SEEN.

.UPDATE...
ISSUED AT 859 AM EDT TUE APR 23 2013

BASED ON THE LATEST RAP MODEL RUN (10Z)...THE 00Z NSSL WAF AND
HOW NICELY THE CURRENT RADAR MOSAICS AND OBSERVATIONS MATCH THOSE
MODELS... I HAVE SIGNIFICANTLY LOWERED THE POPS FOR THE REST OF
THE MORNING INTO THE EARLY AFTERNOON. NEARLY ALL THE RAIN THAT
WILL HAPPEN TODAY WILL BE RELATED TO THE SOUTHERN STREAM WAVE.
THAT WILL MOVE IN FROM THE SOUTHWEST EARLY TO MID AFTERNOON AND
OVERSPREAD THE REST OF THE CWA DURING THE LATE AFTERNOON INTO THE
EARLY EVENING. STILL LOOKS LIKE IT WOULD END AS SOME LIGHT SNOW
BUT NOT MUCH ACCUMULATION IS EXPECTED.

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT TUE APR 23 2013

ANOTHER WET PERIOD IS IN STORE FOR THIS AFTERNOON AND EVENING. THE
GOOD NEWS HOWEVER IS THAT THE MODELS HAVE BACKED OFF ON THE
INTENSITY OF THE MID LEVEL FGEN...WHICH COULD HAVE PUT DOWN POCKETS
OF HEAVIER RAIN. WE WILL STILL SEE FGEN FORCING...BUT IT APPEARS
LESS INTENSE AND IS OVER THE AREA FOR A SHORTER TIME...MAINLY
BETWEEN 22Z AND 06Z. AS A RESULT BELIEVE THE RAINFALL WILL BE
FAIRLY UNIFORM RATHER THAN SEEING POCKETS OF FGEN HEAVIER BULLS
EYE.

A SECONDARY WAVE RIDES UP THE FRONT LATE TONIGHT INTO WEDNESDAY
WHICH MAY EXTEND THE RAIN A BIT LONGER INTO WED OVER THE SE CWA.
HAVE INCREASED POPS THERE. WITH THIS SECOND WAVE BELIEVE NOW THAT
THE HEAVIEST RAINS WILL OCCUR OVER THE SOUTHERN HALF OF THE
CWA...WHERE FEWER HYDRO CONCERNS EXIST. EXPECT THE NORTHERN CWA
WILL SEE BETWEEN A HALF INCH AND THREE QUARTERS OF AN INCH...WHILE
AREAS ALONG AND SOUTH OF I-96 SHOULD GET THREE QUARTERS TO AN INCH
OF RAIN.

IT ALSO BECOMES COLD ENOUGH FOR SOME SNOW ON THE BACKSIDE OF THE
COLD FRONT. WE WILL HAVE TO WATCH THE SECOND WAVE LATE TONIGHT INTO
WED MORN. IF THIS SYSTEM COMES A BIT CLOSER ACCUMS WOULD BE MORE
LIKELY...HOWEVER AT THIS POINT ONLY EXPECT A FEW NORTHERN AREAS
PICKING UP A LIGHT DUSTING.

NOT MUCH OF A BREAK BETWEEN SYSTEMS...AS THE NEXT NORTHERN STREAM
SHORT WAVE ARRIVES WEDNESDAY NIGHT. THIS SYSTEM WILL NOT HAVE DEEP
MOISTURE SINCE IT DOES NOT TAP THE GULF. STILL...THE SHORT WAVE
DEEPENS AS IT MOVES IN AND LIKELY POPS LOOK WARRANTED. ONCE AGAIN
MANY AREAS WILL PROBABLY SEE A RAIN SNOW MIX BY LATE WED NIGHT INTO
THU MORNING...BUT ACCUMS IN THE NORTH SHOULD ONLY BE A DUSTING.

.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 AM EDT TUE APR 23 2013

UPPER PATTERN BECOMES ZONAL AT THE START OF THE LONG TERM IN A SPLIT
FLOW REGIME WITH LOWER MICHIGAN SITUATED IN BETWEEN THE TWO BRANCHES
OF THE JET. THIS WILL PROVIDE FAIRLY BENIGN WEATHER TOWARD THE END
OF THE WEEK AND INTO EARLY PORTIONS OF THE WEEKEND.

MAIN FORECAST ISSUE WAS THE UPPER LOW THAT THE ECMWF WAS DRIFTING
INTO THE GREAT LAKES SUNDAY INTO MONDAY. THE NEW RUN OF THE ECMWF
HAS BACKED OFF ON THIS IDEA KEEPING THE LOW FURTHER SOUTH. AT THIS
TIME HAVE A DRY FORECAST FROM THURSDAY NIGHT THROUGH SUNDAY AS THERE
IS LITTLE IN THE WAY OF DEEP MOISTURE OF LIFT.

HAVE SMALL CHANCES FOR RAIN SHOWERS IN THE FORECAST FOR SUNDAY NIGHT
INTO MONDAY AS THE ECMWF BRINGS SOME MOISTURE NORTH INTO THE AREA IN
SOUTHERLY FLOW. STILL...NOT OVERLY IMPRESSED AND THE LONG TERM LOOKS
MAINLY DRY. TEMPERATURES FRIDAY THROUGH MONDAY LOOK TO BE ABOVE
NORMAL WITH HIGHS WELL INTO THE 60S OVER THE WEEKEND.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 155 PM EDT TUE APR 23 2013

MAIN FOCUS OF THE 18Z FCSTS IS THE RAINFALL MOVING INTO THE AREA
AND THE TREND IN CONDITIONS WITH THE RAIN.

RAINFALL IS EXPANDING AND MOVING IN FROM THE SW THIS AFTERNOON. WE
EXPECT IT WILL HAVE SPREAD OVER ALL OF THE TERMINALS BY 21Z-22Z.
CONDITIONS UPSTREAM UNDER THE RAIN START OUT VFR...AND THEN DROP
DOWN INTO THE IFR CATEGORY UNDER THE CORE. WITH THIS IN MIND...WE
HAVE CONTINUED WITH SOME IFR CONDITIONS AT ALL LOCATIONS SPREADING
WEST TO EAST BEGINNING AROUND 21Z.

RAIN SHOULD THEN GRADUALLY END AFTER MIDNIGHT FROM W/SW TO E/NE.
MOST OF THE PCPN SHOULD REMAIN MAINLY RAIN BEFORE ENDING...HOWEVER
WE CAN NOT RULE OUT SOME SNOWFLAKES MIXING IN RIGHT AT THE END.
VSBYS SHOULD IMPROVE ONCE THE PCPN ENDS OVERNIGHT...BUT LOWER CIGS
IN MVFR CATEGORY WILL LIKELY HOLD ON UNTIL WED MORNING/EARLY
AFTERNOON.

.MARINE...
ISSUED AT 400 AM EDT TUE APR 23 2013

WILL GO AHEAD A ISSUE A SCA FOR TONIGHT INTO WED. COLD ADVECTION
AND BRISK NW WINDS BEHIND THE COLD FRONT WILL CAUSE ROUGH CONDITIONS.

.HYDROLOGY...
ISSUED AT 400 AM EDT TUE APR 23 2013

SMALLER STREAMS AND CREEKS WILL SEE RISES WITH THIS AFTERNOON/S AND
EVENING RAINS. THE LARGER RIVER WILL SEE THEIR FALL SLOWED BY THIS
RAIN...BUT MUCH OF ANY RISE ARE NOT EXPECTED.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT WEDNESDAY
FOR LMZ844>849.

UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...NJJ
HYDROLOGY...JK
MARINE...JK

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

859 AM EDT TUE APR 23 2013

.SYNOPSIS...
ISSUED AT 400 AM EDT TUE APR 23 2013

.UPDATE...
ISSUED AT 859 AM EDT TUE APR 23 2013

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT TUE APR 23 2013

.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 AM EDT TUE APR 23 2013

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 741 AM EDT TUE APR 23 2013

CONDITIONS WILL DETERIORATE THROUGH DAY AS A COLD FRONT APPROACHES
FROM THE WEST. CLOUDS WILL LOWER AND THICKEN WITH WIDESPREAD
SHOWERS BREAKING OUT THIS AFTERNOON. CONDITIONS SHOULD BE VFR THIS
MORNING...WITH MVFR TAKING HOLD THIS AFTERNOON. A PERIOD OF IFR IS
EXPECTED LATE THIS AFTERNOON AND EARLY EVENING AS A BAND OF
HEAVIER RAIN PUSHES THROUGH. THERE IS THE CHANCE FOR A FEW
THUNDERSTORMS BETWEEN 400 PM AND MIDNIGHT...BUT GIVEN LOW
POTENTIAL DID NOT INCLUDE IN THE TAFS. THE BAND OF RAIN WILL MOVE
GRADUALLY TO THE EAST TONIGHT WITH CONDITIONS IMPROVING FROM WEST
TO EAST OVERNIGHT.

.MARINE...
ISSUED AT 400 AM EDT TUE APR 23 2013

WILL GO AHEAD A ISSUE A SCA FOR TONIGHT INTO WED. COLD ADVECTION
AND BRISK NW WINDS BEHIND THE COLD FRONT WILL CAUSE ROUGH CONDITIONS.

.HYDROLOGY...
ISSUED AT 400 AM EDT TUE APR 23 2013

SMALLER STREAMS AND CREEKS WILL SEE RISES WITH THIS AFTERNOON/S AND
EVENING RAINS. THE LARGER RIVER WILL SEE THEIR FALL SLOWED BY THIS
RAIN...BUT MUCH OF ANY RISE ARE NOT EXPECTED.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM EDT WEDNESDAY
FOR LMZ844>849.

UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JK
MARINE...JK

AREA FORECAST DISCUSSION

NWS KANSAS CITY/PLEASANT HILL MO

550 AM CDT Tue Apr 23 2013

.SHORT TERM...(Today and Tonight)
Issued at 412 AM CDT TUE APR 23 2013

A very challenging forecast this morning with several concerns
through the upcoming 24 hours. Early this morning, an initial wave of
warm advection showers and embedded thunderstorms continue to slowly
lift northeast into the CWA. Rainfall amounts haven`t been overly
impressive through the night, but those numbers should steadily
increase through daybreak as this wave of rain moves across the
southern half of the CWA.

The big story today will be with a very late season snowfall
potential over the northwestern third of the CWA. Colder air has
surged southward into the CWA this morning, a little bit more
aggressive than models indicated. By daybreak, several pieces of
guidance indicated that a weak 700 mb vort max will track eastward
out of NW Kansas and into the northwestern corner of the CWA.
Impressive 700:600 mb frontogenesis already producing light to
moderate snowfall accumulations in northwestern Kansas will begin to
re-orientate itself as the aforementioned shortwave tracks east.
RAP/NAM guidance indicate this area of lift is expected to narrow
it`s axis as it moves into the CWA. Cross sections through this axis
reveal layered -EPV just above this area of frontogenesis suggesting
that there will be the potential for a very narrow band of moderate
snow.

As always, many variables come into play to address just how much
snow could accumulate, surface temperatures, snowfall rate, wet bulb
temperatures. There will likely be a very defined cutoff on the
southern edge of potential accumulations given warm air in place and
warm ground, but given the forcing see the potential for 1-2" of
snow and wouldn`t be surprised if the precip band really gets
organized to see a few isolated higher amounts along a line from St.
Joseph to Maryville and Bethany.

This band of frontogenesis will quickly begin to diminish late in
the morning and HRRR/RAP guidance indicates that the introduction of
dry air aloft should shut off any moderate precipitation. However,
soundings do suggest the potential for lingering flurries, sprinkles
or sleet into early afternoon.

Tonight: The second part of the story will be with overnight low
temperatures. An already cold day will lead to an even colder night
as clouds slowly clear from NW to SE. Current projections indicate
that readings will fall below 30 in many areas, with the exception
perhaps in the far SE where cloud cover may linger longer. Will go
ahead and issue a freeze warning for areas which will fall at or
below 30 degrees for a sustained amount of time. Interestingly
enough, the record low for Kansas City is 32 degrees set back in
1893. For St. Joseph, the record low is 30 degrees set back in 1996.

.LONG TERM...(Wednesday through Monday)
Issued at 412 AM CDT TUE APR 23 2013

Wednesday night-Thursday morning:

A fast moving clipper type system will swing through the Upper MS
Valley with the southern extension of the system grazing northern MO
as a cold front drops south through the CWA. Could see scattered
light showers on the southern end of the trough skirt northern MO
during the evening hours.

Cool high pressure will slide into eastern KS/western MO. The
combination of clear skies, light winds and temperatures/dewpoints
near the freezing mark provide a favorable setting for some frost
towards sunrise Thursday.

Thursday night-Friday:

With minor differences this far out the medium range models continue
to show decent run-to-run continuity with respect to a compact
vorticity max/shortwave ejecting out of the desert southwest and
tracking through KS/OK. As the system moves out into the Southern
and Central Plains it will interact with an increasing
south-southwesterly low level jet that will be pulling up a better
supply of low-level moisture. The ensuing isentropic ascent combined
with the upper dynamics will likely result in scattered convection
spreading across KS/MO. Best bet for rain in our CWA will be south
of I-70. Favored the slower ECMWF/NAM solutions and the 00Z. GFS is
now trending that way as well so slowed down arrival of
precipitation.

Saturday-Monday:

Will finally get an extended taste of seasonal temperatures as
significant warming through h8 spreads across the central U.S.
Progged soundings support highs into the upper 60s-middle 70s.

While the weekend should remain dry for the most part there are
considerable differences between the GFS and ECMWF/GEM. The GFS drops
a moderately strong upper trough through the Northern
Rockies/Northern Plains Sunday/Sunday night while the latter two
models are more muted, slower and depict an upper ridge over the
Central Plains and Mid MO Valley. So, have low confidence on
precipitation forecast Sunday night-Monday and side with climatology
this far out.

.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 545 AM CDT TUE APR 23 2013

Regional radar reflectivity indicates that the widespread initial
area of rain will move east of the terminals within the upcoming
hour. Short range guidance from the HRRR handles this setup well,
lifting visibilities through 13-14Z before additional precipitation in
central Kansas arrives. For the KC terminals, appears a rain/snow
mixture may be possible as this secondary wave of precip moves
through, with MVFR to periodic IFR ceilings through the morning.
Further north, St. Joseph stands the highest probability of seeing a
complete transition to light snow.

Precipitation may dwindle to drizzle by early in the afternoon before
ending by 20z. Ceilings will slowly rise this afternoon and the
clearing line should approach the terminals after midnight tonight.

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FREEZE WARNING from 1 AM to 8 AM CDT Wednesday FOR KSZ025-057-
060-102>105.

MO...FREEZE WARNING from 1 AM to 8 AM CDT Wednesday FOR MOZ001>008-
011>017-020>024-028>031-037-038-043-053.

SHORT TERM...31
LONG TERM...MJ
AVIATION...31

AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

1138 AM CDT TUE APR 23 2013

.UPDATE...

UPDATED TO LOWER TEMPERATURES AND CURRENT PRECIP TRENDS

.DISCUSSION...

VISIBLE SATELLITE IMAGERY THIS MORNING INDICATES A GOOD SNOW PACK
OVER THE NORTHWEST CWA AND THIS...ALONG WITH LOW LEVEL CAA...IS
EXPECTED TO REALLY LIMIT TEMPERATURES THIS AFTERNOON. WE HAVE
LOWERED HIGHS SEVERAL CATEGORIES INTO THE LOWER 30S IN THIS
AREA...AND THIS MAY NOT BE COLD ENOUGH. LOOKS LIKE A RECORD MIN
MAX IS LIKELY AT BOTH OMA/OFK TODAY. WE ALSO LOWERED HIGHS A TOUCH
IN THE SOUTHERN CWA WHERE THE CLOUDS/PRECIP ARE LIKELY TO HANG ON
A BIT LONGER. AS FAR AS PRECIP...RADAR TRENDS INDICATE A GENERAL
DECREASE IN THE HIGHER RETURNS IN THE SOUTH AND THIS TREND SHOULD
CONT THROUGH THE AFTERNOON. THE SOUTHERN CWA DOES REMAIN IN THE
RIGHT REAR ENTRANCE REGION OF THE AN UPPER LEVEL JET...AND THIS
FAVORABLE LARGE-SCALE FORCING FOR ASCENT MAY KEEP SOME SPRINKLES
OR FLURRIES GOING THROUGH THE AFTERNOON...THE ACCUMULATING
SNOWFALL IS OVER FOR THIS AREA.

NEW GRIDS/ZFP UPDATES HAVE ALREADY BEEN SENT.

.AVIATION...
18Z TAFS FOR KOMA...KOFK...KLNK

MVFR CIGS CONT TO HANG ON AT LNK BUT VFR CONDS HAVE RETURN TO
OMA/OFK...AND THIS SHOULD BE THE GENERAL TREND THROUGH THE TAF
PERIOD AS WELL. GUSTY NORTHWEST WINDS WILL CONTINUE INTO THE EARLY
AFTERNOON BEFORE THE GUSTS DIMINISH...WITH SUSTAINED WINDS BELOW
12 KT BY EARLY THIS EVENING THROUGH THE END OF THE TAF PERIOD.

PREV DISCUSSION... /ISSUED 351 AM CDT TUE APR 23 2013/

DISCUSSION...
FORECAST CONCERNS TODAY WILL BE LIGHT SNOW POTENTIAL FOR SOUTHERN
PARTS OF CWA.

THE SURFACE COLD FRONT HAS PUSHED WELL TO THE SOUTH INTO SOUTHEAST
KANSAS AND NORTHWEST MISSOURI WITH SURFACE HIGH PRESSURE BUILDING
INTO THE REGION. AT H3...THE 120KT JET WAS OVERHEAD AND THE H5 TROF
FROM MONTANA TO NEVADA/UTAH STILL HAD 40DM HT FALLS WITH IT. THE
H3 JET WILL RE-CURVE SLIGHTLY NORTHEAST AS THE H5 TROF SWINGS
THROUGH THE PLAINS TODAY. THIS WILL STRENGTHEN THE MID LEVEL
FRONTOGENETIC FORCING IN NORTHEAST KANSAS AND H7 WARM AIR
ADVECTION BEFORE PUSHING EASTWARD THIS AFTERNOON. DRY LOW LEVELS
WILL BE UNDERCUTTING THE MOIST MID LEVELS...HOWEVER SOUTHEAST
NEBRASKA AND FAR SOUTHERN IOWA LOOKED TO BE CLIPPED WITH
PRECIPITATION WITH THIS STRONGER MID LEVEL FORCING. THE LATEST
WSR-88D MOSAIC HAS THE CONVECTION CLOSER TO THE FRONT OVER
SOUTHERN KANSAS WITH A BAND OF RAIN AND SNOW TRACKING NORTHEAST
ACROSS NORTHERN KANSAS. THE 03Z RAP/01Z HRRR AND LATEST 06Z
HRRR/07Z RAP HAVE BEEN CONSISTENT IN LIFTING SOME LIGHT SNOW INTO
SOUTHEAST NEBRASKA THIS MORNING AND SHIFT IT OUT OF THE AREA BY
18Z. WILL MAINTAIN HIGH PROB OF PRECIPITATION FOR FAR SOUTHEAST
NEBRASKA AND FAR SOUTHERN IOWA. FNB HAS BEEN REPORTING LIGHT RAIN
AND COLD AIR SHOULD CONTINUE TO DECREASE TEMPERATURES FOR A
CHANGEOVER TO SNOW. DID MENTION SOME LIGHT ACCUMULATIONS BEATRICE
TO CLARINDA SOUTHWARD WITH A DUSTING TO AN INCH OR SO AT
FNB...REDUCING THE CHANCES SIGNIFICANTLY AFT 18Z. BREEZY TO WINDY
NORTH WINDS AND COLD AIR ADVECTION TODAY WILL HOLD MOST LOCATIONS
TO THE UPPER 30S AND LOWER 40S.

SURFACE HIGH PRESSURE BUILDS IN TONIGHT WITH MOSTLY CLEAR...COLD
CONDITIONS AND DIMINISHING WINDS. TEMPERATURES WILL DROP INTO THE
20S FOR MOST SPOTS.

WEDNESDAY...THERE WILL BE SOME WARM AIR ADVECTION AHEAD OF A COLD
FRONTAL PASSAGE AND ANOTHER SHORTWAVE TROF DROPPING SOUTH IN THE
FLOW ALOFT. FORECAST SOUNDINGS IMPLY INSTABILITY SHOWERS ARE
POSSIBLE WITH HIGHS IN THE 40S AND 50S. MID LEVEL RIDGING AND
WARMER H85 TEMPERATURES RETURN FOR THURSDAY AHEAD OF A SURFACE
TROF WITH HIGHS IN THE 60S. DEEPER MOISTURE RETURNS AS THE LOW
LEVEL JET STRENGTHENS THURSDAY NIGHT AND FRIDAY. AS A SHORTWAVE
PASSES THROUGH...SOME OF THE THUNDERSTORMS ACROSS KANSAS COULD
SPREAD INTO FAR SOUTHERN NEBRASKA AND SOUTHWEST IOWA.

THE MODELS ARE IN GOOD AGREEMENT THROUGH SATURDAY. HIGH SATURDAY
AND SUNDAY SHOULD WARM TO AT OR ABOVE NORMAL IN THE LOWER 70S.
THERE IS A SUBTLE WAVE THAT COULD BRING SOME ISOLATED SHOWERS AND
THUNDERSTORMS. THE MODELS DO NOT AGREE ON MUCH MOISTURE WILL BE
AVAILABLE...BUT DO SHOW SOME INSTABILITY WITH THE WEAK WAVE. MAY
NEED TO ADD SOME CHANCE OF PRECIP FOR THIS. SUNDAY AND
BEYOND...THERE ARE SOME TIMING ISSUES WITH THE NEXT SHORTWAVE
TROF. GFS IS FASTER...WITH THE EC SLOWER. DO HAVE SOME LOW POPS
SUNDAY NIGHT AND MONDAY...BUT THESE COULD HOLD OFF UNTIL LATER IN
THE WEEK.

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

616 AM CDT TUE APR 23 2013

.AVIATION...12Z TAFS FOR KOMA...KLNK AND KOFK. BAND OF LIGHT SNOW
MOVING THROUGH SOUTHEAST NEBRASKA THIS MORNING...AND BELIEVE THAT
KLNK COULD BE JUST ON THE EDGE. MVFR CLOUDS THAT HAD EXISTED HAVE
SCATTERED OUT TEMPORARILY AT KLNK/KOMA...BUT STILL CAN`T RULE OUT
AN MVFR CEILING YET THIS MORNING. ALSO THINK THAT KLNK COULD STILL
SEE AN OCCASIONAL FLURRY THIS MORNING IF MVFR CEILINGS CAN
REDEVELOP FROM 14 TO 18Z. OTHERWISE...NO OTHER SIGNIFICANT
AVIATION ISSUES THROUGH THE PERIOD.

.PREV DISCUSSION... /ISSUED 351 AM CDT TUE APR 23 2013/

DISCUSSION...
FORECAST CONCERNS TODAY WILL BE LIGHT SNOW POTENTIAL FOR SOUTHERN
PARTS OF CWA.

SURFACE HIGH PRESSURE BUILDS IN TONIGHT WITH MOSTLY CLEAR...COLD
CONDITIONS AND DIMINISHING WINDS. TEMPERATURES WILL DROP INTO THE
20S FOR MOST SPOTS.

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

351 AM CDT TUE APR 23 2013

.DISCUSSION...
FORECAST CONCERNS TODAY WILL BE LIGHT SNOW POTENTIAL FOR SOUTHERN
PARTS OF CWA.

THE SURFACE COLD FRONT HAS PUSHED WELL TO THE SOUTH INTO SOUTHEAST
KANSAS AND NORTHWEST MISSOURI WITH SURFACE HIGH PRESSURE BUILDING
INTO THE REGION. AT H3...THE 120KT JET WAS OVERHEAD AND THE H5 TROF
FROM MONTANA TO NEVADA/UTAH STILL HAD 40DM HT FALLS WITH IT. THE
H3 JET WILL RE-CURVE SLIGHTLY NORTHEAST AS THE H5 TROF SWINGS
THROUGH THE PLAINS TODAY. THIS WILL STRENGTHEN THE MID LEVEL
FRONTOGENETIC FORCING IN NORTHEAST KANSAS AND H7 WARM AIR
ADVECTION BEFORE PUSHING EASTWARD THIS AFTERNOON. DRY LOW LEVELS
WILL BE UNDERCUTTING THE MOIST MID LEVELS...HOWEVER SOUTHEAST
NEBRASKA AND FAR SOUTHERN IOWA LOOKED TO BE CLIPPED WITH
PRECIPITATION WITH THIS STRONGER MID LEVEL FORCING. THE LATEST
WSR-88D MOSAIC HAS THE CONVECTION CLOSER TO THE FRONT OVER
SOUTHERN KANSAS WITH A BAND OF RAIN AND SNOW TRACKING NORTHEAST
ACROSS NORTHERN KANSAS. THE 03Z RAP/01Z HRRR AND LATEST 06Z
HHRR/07Z RAP HAVE BEEN CONSISTENT IN LIFTING SOME LIGHT SNOW INTO
SOUTHEAST NEBRASKA THIS MORNING AND SHIFT IT OUT OF THE AREA BY
18Z. WILL MAINTAIN HIGH PROB OF PRECIPITATION FOR FAR SOUTHEAST
NEBRASKA AND FAR SOUTHERN IOWA. FNB HAS BEEN REPORTING LIGHT RAIN
AND COLD AIR SHOULD CONTINUE TO DECREASE TEMPERATURES FOR A
CHANGEOVER TO SNOW. DID MENTION SOME LIGHT ACCUMULATIONS BEATRICE
TO CLARINDA SOUTHWARD WITH A DUSTING TO AN INCH OR SO AT
FNB...REDUCING THE CHANCES SIGNIFICANTLY AFT 18Z. BREEZY TO WINDY
NORTH WINDS AND COLD AIR ADVECTION TODAY WILL HOLD MOST LOCATIONS
TO THE UPPER 30S AND LOWER 40S.

SURFACE HIGH PRESSURE BUILDS IN TONIGHT WITH MOSTLY CLEAR...COLD
CONDITIONS AND DIMINISHING WINDS. TEMPERATURES WILL DROP INTO THE
20S FOR MOST SPOTS.

.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.

STRONG NORTHERLY SURFACE FLOW WILL CONTINUE THROUGH 18Z THEN
GRADUALLY DIMINISH 18Z-00Z AS HIGH PRESSURE BUILDS INTO THE AREA.
MVFR CIGS LIKELY THROUGH 18Z BECOMING VFR THEREAFTER. SPEED MAX
ACROSS KANSAS IS EXPECTED TO SPREAD LIGHT SNOW ALONG THE SOUTHERN
BORDER WITH SOME LIGHT SNOW POSSIBLE AS FAR NORTH AS KLNK THROUGH
12Z.

FOBERT

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

ZAPOTOCNY

AREA FORECAST DISCUSSION

NWS RALEIGH NC

310 AM EDT TUE APR 23 2013

.SYNOPSIS...
AN AREA OF HIGH PRESSURE WILL PERSIST OVER CENTRAL NORTH CAROLINA
THROUGH WEDNESDAY WHILE AN AREA OF LOW PRESSURE TRACKS SLOWLY
NORTHEAST OFF THE MID ATLANTIC AND NEW ENGLAND COAST THROUGH
TONIGHT. A COLD FRONT WILL CROSS THE REGION WEDNESDAY NIGHT.

.NEAR TERM /THROUGH TUESDAY NIGHT/...
AS OF 942 PM MONDAY...

TONIGHT...
SURFACE HIGH PRESSURE WILL CONTINUE TO EXTEND OVER CENTRAL NC FROM
THE CENTER LOCATED NE OF NOVA SCOTIA TONIGHT. MEANWHILE...SHOWERS ON
THE NORTHWEST SIDE OF A LOW PRESSURE SYSTEM DEVELOPING OFF THE NC
COAST HAVE PUSHED WESTWARD THIS EVENING. ALTHOUGH THE LIFT IS NOT
ALL THAT IMPRESSIVE IN THE MID LEVELS...THE NAM SHOWS AN AREA OF QG
FRONTOGENESIS AND SOME MID LEVEL DIVERGENCE OVER THE AREA WHERE
SHOWERS HAVE DEVELOPED. AS SUCH...THE NAM AND HRRR APPEAR TO HAVE
THE BEST HANDLE ON THE RAIN...SO HAVE INCREASED CHANCES ACCORDINGLY
TONIGHT. SCATTERED SHOWERS EXPECTED TO SPREAD WEST TOWARD THE TRIAD
THROUGH 12Z. STILL EXPECT WINDS TO STAY GUSTY OVERNIGHT AS THE
PRESSURE GRADIENT INCREASES OVER THE AREA. CLOUDS ALREADY EXTEND
ACROSS MOST OF THE FORECAST AREA...WITH TEMPS CURRENTLY HOLDING IN
THE 50S. STILL ANTICIPATE LOWS IN THE LOW TO MID 40S OVERNIGHT. -KC

TUESDAY AND TUESDAY NIGHT...
WITH THE SURFACE LOW MOVING NORTHEAST AWAY FROM THE AREA ON
TUESDAY...GUIDANCE INDICATES CLEARING FROM WEST TO EAST THROUGHOUT
THE DAY. GIVEN THE SHALLOW DEPTH OF SATURATION IN THE WEST...EXPECT
BREAKS IN CLOUD COVER WILL BE ABLE TO DEVELOP IN THE MORNING.
FURTHER EAST...FORECAST SOUNDINGS SHOW ABOUT A 3000FT LATER OF
STRATUS...WHICH WILL TAKE LONGER TO SCOUR VIA DRYING FROM ALOFT AND
HEATING. HOWEVER...MOST AREAS SHOULD BE PARTLY CLOUDY TO MOSTLY
SUNNY BY EARLY AFTERNOON....AND HIGHS WILL ACCORDINGLY BE WARMEST IN
THE SOUTH AND WEST IN THE MID TO UPPER 60S. THE RIDGE AXIS WILL THEN
SHIFT EAST ACROSS CENTRAL NC TUESDAY NIGHT...ALLOWING WINDS TO DIE
OFF AND FAVOR AT LEAST PATCHY FOG. LOWS IN THE UPPER 40S. -SMITH

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 230 AM TUESDAY...

WEDNESDAY AND WEDNESDAY NIGHT TO FOLLOW SHORTLY.

THURSDAY AND THURSDAY NIGHT:
EXPECT THE SURFACE FRONT WILL BE TO THE SOUTH OF THE AREA BY 12Z
THURSDAY. HOWEVER... THE 850 MB FRONT WILL LIKELY LAG BEHIND A
BIT... HELPING TO SUPPORT CONTINUED CHANCES FOR SOME SHOWERS AT
LEAST DURING THE MORNING HOURS... BEFORE IT IS PUSHED TO THE SOUTH
AND EAST OF THE AREA DURING THE AFTERNOON AS A SECONDARY S/W CROSSES
THE CENTRAL NC. WRT THE TIMING OF THE PRECIP... THE 00Z GFS AND
CANADIAN APPEAR TO ON THE FAST SIDE OF THE OPERATIONAL GUIDANCE...
WITH THE 00Z NAM JUST A BIT SLOWER... WHILE THE 12Z ECMWF IS MUCH
SLOWER. GIVEN SOME OF THE GFS ENSEMBLE MEMBERS ARE SHOWING THE
POTENTIAL TO SLOW THE DEPART OF THE PRECIP... WILL TREND THE
FORECAST CLOSER TO A BLEND OF THE 00Z NAM AND 12Z ECMWF. THIS YIELDS
PRECIP CHANCES ENDING ACROSS EASTERN PORTIONS OF THE AREA BY MID
AFTERNOON OR SO... WITH PARTLY TO MOSTLY CLOUDY SKIES POSSIBLY
LINGERING THROUGH THE AFTERNOON ACROSS OUR FAR EASTERN COUNTIES.
THUS... HAVE TRENDED HIGH TEMPS CLOSER TO THE MET GUIDANCE... WHICH
SHOWS HIGHS RANGING FROM THE MID 60S (POSSIBLY EVEN LOWER 60S)
ACROSS OUR FAR EASTERN COUNTIES... TO THE UPPER 60S TO EVEN 70
DEGREES ELSEWHERE... WHERE A WESTERLY DOWNSLOPE FLOW SHOULD HELP
PROMOTE CLEARING SKIES DURING THE AFTERNOON HOURS WITH LOCATIONS
ACROSS THE WESTERN PIEDMONT MOSTLY SUNNY BY AT LEAST MID AFTERNOON
(WHERE TEMPS MAY BE THE WARMEST).

HIGH PRESSURE WILL BUILD INTO THE AREA THURSDAY NIGHT/FRIDAY
MORNING... WITH A GENERAL WEST-NORTHWEST DRY FLOW ALOFT. THIS SHOULD
YIELD CLEAR SKIES... WITH A GENERAL LIGHT NORTHERLY BREEZE. THUS...
EXPECT LOW TEMPS WILL AGAIN RETURN TO BELOW NORMAL FOR THIS TIME OF
YEAR. EXPECT LOWS FRIDAY MORNING RANGING FROM THE LOWER 40S TO THE
UPPER 40S... WITH PERHAPS A FEW OF THE USUAL RURAL COLD LOCATIONS
DROPPING TO AROUND 40 OR SO.

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 305 AM TUESDAY...

ERY BRIEF WEAK S/W RIDGING WILL BUILD ACROSS THE AREA FRIDAY/FRIDAY
NIGHT... BEFORE THE NEXT DISTURBANCE APPROACHES THE AREA FROM THE
SW. THIS DISTURBANCE IS CURRENTLY LOCATED WELL OFF THE SOUTHWEST
U.S. COAST AROUND 30N AND 130W. THUS... MEDIUM RANGE MODELS CONTINUE
TO STRUGGLE WITH HOW THE SYSTEM EVOLVES AS IT MOVES ACROSS SOUTHERN
U.S. AND INTO OUR REGION BY THIS WEEKEND. THE GFS REALLY SHEARS THE
SYSTEM OUT AS IT MOVES TOWARDS OUR AREA... WHILE THE ECMWF INITIALLY
DOES... BEFORE IT CUTS OFF INTO A CLOSED LOW JUST TO OUR WEST
ALLOWING FOR GOOD MOISTURE TRANSPORT INTO OUR REGION FOR AT LEAST
THE SECOND HALF OF THE WEEKEND. HOW MUCH PRECIP ALONG WITH THE
TIMING IS STILL A BIT IN QUESTION. HOWEVER... IT STILL APPEARS WE
WILL HAVE RATHER UNSETTLED WEATHER ACROSS CENTRAL NC FROM LATE
SATURDAY INTO SUNDAY... WITH AT LEAST LOTS OF CLOUD AND SPOTTY
PRECIP LINGERING INTO NEXT WEEK.

TEMPS OUTSIDE OF FRIDAY WILL BE A CHALLENGE... AS THE AFOREMENTIONED
SURFACE HIGH (WHICH BUILDS INTO THE AREA BEHIND THE FRONT ON
THURSDAY) IS EXPECTED TO SHIFT OFFSHORE AND AND LINGER OFF THE
NORTHEAST U.S. COAST INTO EARLY NEXT WEEK.. THUS... ONCE WE START TO
GET PRECIP FALLING INTO THE DRY SURFACE RIDGE EXPECT WE WILL LIKELY
SEE AT LEAST SOME FORM OF DAMMING AIRMASS DEVELOP ACROSS PORTIONS OF
THE PIEDMONT. EXPECT HIGH TEMPS ON FRIDAY WILL BE IN THE UPPER 60S
TO LOWER 70S... WITH LOWS SATURDAY MORNING IN THE MID TO UPPER 40S
TO AROUND 50 ACROSS THE SOUTH AND SOUTHWEST... WITH MID AND HIGH
CLOUDS ALREADY STARTING TO STREAM BACK INTO THE AREA. TEMPS DURING
THE REMAINDER OF THE PERIOD WILL BE DRIVE LARGELY BY THE PRECIP AND
POSITIONING OF THE SURFACE HIGH. THUS... FOR NOW HAVE LOWERED TEMPS
IN THE DAMMING REGION FROM LATE SATURDAY INTO SUNDAY (WHEN THE BEST
CHANCE OF PRECIP WILL BE)... WITH A SLIGHT INDICATION OF THIS FOR
MONDAY. THIS YIELDS HIGH TEMPS GENERALLY BELOW NORMAL IN THE FAVORED
DAMMING REGION OF THE NORTHWEST PIEDMONT... TO SLIGHT BELOW TO NEAR
NORMAL ACROSS THE SOUTHEAST.

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 140 AM TUESDAY...

A MOIST LOW LEVEL E-NE FLOW WILL CONTINUE TO ADVECT ATLANTIC
MOISTURE INTO CENTRAL NC OVERNIGHT...MAINTAINING CURRENT MVFR
CEILINGS OR LOW END VFR CEILINGS THROUGH DAYBREAK. POCKETS OF IFR
CEILINGS HIGHLY LIKELY FROM KRDU EASTWARD INCLUDING KRWI AND
KFAY...WITH THE FREQUENCY OF IFR CEILINGS MORE LIKELY EAST AND NORTH
OF KRWI.

LATER THIS MORNING...AN AREA OF LOW PRESSURE WILL BEGIN TO PULL AWAY
FROM THE NC COAST. AS THIS WEATHER SYSTEM LIFTS N-NE...THE LOW LEVEL
FLOW WILL BECOME MORE NLY...ENDING THE MOISTURE ADVECTION. THIS WILL
LEAD TO A LIFTING/DISSIPATION OF THE MVFR CEILINGS...BEGINNING BY
9-10 AM IN THE PIEDMONT AND SANDHILLS...AND THE COASTAL PLAIN BY 10
AM-11 AM. THE BULK OF CENTRAL NC WILL EXPERIENCE VFR CONDITIONS BY
EARLY AFTERNOON.

SFC WINDS...CURRENTLY NE SUSTAINED 10KTS WITH GUSTS 16-19KTS WILL
SUBSIDE AND BECOME NLY BY DAYBREAK. BY LATE LATE MORNING INTO THE
AFTERNOON...SFC WINDS WILL BECOME LIGHT AND VARIABLE.

TONIGHT...MAY SEE AN EPISODE OF MVFR-IFR VISIBILITY DUE TO
FOG...ESPECIALLY ACROSS THE SANDHILLS...COASTAL PLAIN...AND EASTERN
PIEDMONT. THIS FOG MAY IMPACT OPERATIONS AT KRDU/KRWI/KFAY. ANY FOG
AND LOW CLOUDS THAT DEVELOP WILL BURN OFF BY 9-10 AM WEDNESDAY
MORNING.

VFR CONDITIONS ANTICIPATED FOR WEDNESDAY. A SURFACE COLD FRONT WILL
CROSS THE REGION WEDNESDAY NIGHT AND EXIT THE REGION THURSDAY
MORNING. THIS WEATHER SYSTEM WILL CAUSE A PERIOD OF MVFR CEILINGS
ALONG WITH AREAS OF RAIN SHOWERS AND MAYBE A THUNDERSTORM OR TWO.

VFR CONDITIONS WILL RETURN TO CENTRAL NC THURSDAY AFTERNOON AND
PERSIST THROUGH EARLY SATURDAY. MAY SEE A BRIEF PERIOD OF SUB VFR
VISIBILITY SATURDAY MORNING. THE NEXT LOW PRESSURE SYSTEM MAY BRING
MVFR CEILINGS TO THE WESTERN PIEDMONT INCLUDING THE TRIAD REGION BY
LATE SATURDAY.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...WSS
NEAR TERM...KC/SMITH
SHORT TERM...WSS/BSD
LONG TERM...BSD
AVIATION...WSS

AREA FORECAST DISCUSSION

NWS RALEIGH NC

140 AM EDT TUE APR 23 2013

.NEAR TERM /THROUGH TUESDAY NIGHT/...
AS OF 942 PM MONDAY...

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 PM MONDAY...

FOR WEDNESDAY: RISING SURFACE DEW POINTS WITHIN FAIRLY STABLE LOW
LEVELS... A DEPARTING SURFACE RIDGE... VERY LIGHT SURFACE FLOW FROM
THE SOUTHWEST... AND A LACK OF CLOUDS ALL SUPPORT AT LEAST PATCHY
FOG HOLDING INTO MID MORNING... ALTHOUGH WITH A BIT MORE MOISTURE
AND STRONGER LOW LEVEL FLOW IN THE TRIAD REGION... STRATUS MAY
DOMINATE HERE. AS THE WEAK SURFACE HIGH SHIFTS OFF THE SOUTHEAST
COAST WEDNESDAY... SOUTHWESTERLY FLOW FLOW WILL STRENGTHEN OVER
CENTRAL NC AHEAD OF THE COLD FRONT PROJECTED TO PUSH INTO WRN NC
EARLY-MID AFTERNOON. WE WILL STILL BE DOMINATED BY THE MID LEVEL
RIDGING AND DRY AIR HOWEVER... WITH A PROMINENT WARM NOSE AT 800-700
MB... SO INSTABILITY WILL BE LOW TO ABSENT AND MUCH OF THE DAY WILL
REMAIN DRY. THE EXCEPTION WILL BE THE TRIAD... WHICH SHOULD SEE A
FEW SHOWERS/STORMS MOVING IN VERY LATE IN THE AFTERNOON...
ACCOMPANYING THE RISING MID LEVEL LAPSE RATES TO OVER 6 C/KM AND THE
INCREASING LOW LEVEL MOISTURE TRANSPORT. BUT WITH THE MID LEVEL
VORTICITY SHEARING OFF QUICKLY NE ALONG THE APPALACHIANS ALONG WITH
THE MEAGER LOW LEVEL JET (JUST 20-25 KTS)... ANY PRECIP SHOULD BE
VERY LIGHT AND PATCHY. SREF PROBABILITIES OF MEASURABLE RAIN SUPPORT
THIS WITH ONLY LOW CHANCES GETTING INTO THE NW CWA TOWARD EVENING.
ABOVE-NORMAL THICKNESSES (PROJECTED TO CLIMB ABOVE 1380 METERS)
TEMPERED BY INCREASING HIGH CLOUDS THROUGH THE DAY AND SCATTERED
FLAT CUMULUS IN THE AFTERNOON SUPPORT HIGHS OF 74-80... VALUES ALSO
INDICATED BY THE DRY ADIABATIC LOW LEVEL THERMAL STRUCTURE.

FOR WEDNESDAY NIGHT/THURSDAY: AS THE MID LEVEL FLOW OVER OUR REGION
BECOMES ROUGHLY PARALLEL TO THE SURFACE FRONT... BETWEEN THE FIRST
SHORTWAVE TROUGH THAT SHEARS TO THE NORTHEAST TOWARD SE CANADA AND
THE SECOND SHOT OF SHORTWAVE ENERGY WHICH CROSSES THE UPPER MIDWEST
AND GREAT LAKES...THE SURFACE FRONT IS LIKELY TO MAKE ONLY A VERY
SLOW SOUTHEASTWARD PROGRESSION ACROSS NC WEDNESDAY NIGHT INTO EARLY
THURSDAY. GIVEN THE ANAFRONTAL STRUCTURE TO THIS SYSTEM... WE SHOULD
SEE RAIN AND A FEW STORMS SPREADING SLOWLY EAST WEDNESDAY NIGHT JUST
BEHIND THE FRONT. THE MID LEVEL VORTICITY AND LOW LEVEL JET BOTH
SHEARING OFF TO OUR NORTHEAST... ALONG WITH THE UPPER DIVERGENCE
MAX... WILL RESULT IN WANING DYNAMIC FORCING FOR ASCENT. BUT
STEEPENING MID LEVEL LAPSE RATES (TO OVER 6.25 C/KM) AND THE
POTENTIAL FOR ELEVATED CONVECTION (MUCAPE OF 100-200 J/KG) SHOULD
OFFSET THIS ENOUGH FOR CHANCE POPS... GIVEN THE ANTICIPATED CLIMB IN
PRECIP WATER VALUES TO AROUND 1.25 IN. WILL FOCUS THE HIGHEST POPS
LATE WEDNESDAY EVENING THROUGH EARLY THURSDAY MORNING OVER THE WRN
AND NRN PIEDMONT... BUT WILL LIMIT POPS TO JUST CHANCE. SREF
PROBABILITIES OF MEASURABLE RAIN START OFF NEAR 50% OVER THE
MOUNTAINS WEDNESDAY EVENING BUT FALL OFF QUICKLY WEDNESDAY NIGHT AS
THE FRONT SWEEPS EASTWARD... FURTHER SUPPORTING KEEPING POPS AND
AMOUNTS ON THE LOW END. PRECIP SHOULD TAPER OFF TO PATCHY DRIZZLE
LATE WEDNESDAY NIGHT (IN NW) THROUGH THURSDAY MORNING AS THE MID
LEVEL DRY OUT A BIT. AS THE MID LEVEL TROUGH MOVES THROUGH THE GREAT
LAKES INTO THE ST LAWRENCE VALLEY AND HELPS KICK THE SURFACE-850 MB
FRONTAL ZONE TO OUR SE THURSDAY AFTERNOON... MODEL FORECAST
SOUNDINGS SHOW ENOUGH DRYING JUST OFF THE SURFACE WITH AN INCREASING
DOWNSLOPE COMPONENT FOR SLOWLY CLEARING SKIES WEST-TO-EAST IN THE
AFTERNOON. HOWEVER.. CONFIDENCE IN SUCH CLEARING IS USUALLY REDUCED
IN THESE SITUATIONS WITH A MESOHIGH BEHIND AN ANAFRONT... AS THE
FLOW IS TYPICALLY TOO LIGHT AND VERTICAL MOTIONS TOO WEAK TO
DISPERSE THE RESIDUAL LOW LEVEL MOISTURE. AS A RESULT WILL BE MORE
PESSIMISTIC WITH CLOUD COVER THURSDAY... AND WILL HOLD ONTO THE
EARLIER FORECAST OF BELOW NORMAL TEMPS... ALTHOUGH A GREATER
DURATION OF LOW LEVEL DOWNSLOPE COMPONENT FLOW SHOULD YIELD SOME
AFTERNOON RECOVERY IN THE WRN FORECAST AREA... PLUS THE BRUNT OF THE
COOLER POST-FRONTAL AIR WILL BE SLOWED BY THE MOUNTAINS. MORNING
LOWS 50-58. HIGHS 64-72. -GIH

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 245 PM MONDAY...

FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT: THE MID LEVEL TROUGH AXIS
WILL PUSH TO OUR EAST THURSDAY NIGHT WITH THE COLD FRONT SLIPPING TO
OUR SOUTHEAST... AS A LARGE HIGH PRESSURE AREA BUILDS IN FROM THE
MISS VALLEY. EXPECT GRADUALLY CLEARING SKIES OVERNIGHT... ALTHOUGH
FORECAST SOUNDINGS SUGGEST THAT SHALLOW FOG BANKS ARE POSSIBLE.
PLEASANT AND DRY WEATHER AND SLIGHTLY BELOW-NORMAL TEMPS SHOULD
FOLLOW ON FRIDAY AS THE SURFACE HIGH RIDGES INTO NC WHILE ITS CENTER
CROSSES THE OHIO VALLEY HEADING TOWARD THE MIDATLANTIC REGION.
MODELS SHOW THE HIGH SHIFTING NE OFF THE MIDATLANTIC COAST TO NEW
ENGLAND FRIDAY NIGHT... PROPELLED BY ANOTHER SHORTWAVE TROUGH
CROSSING THE CENTRAL CONUS. THE ENSUING RETURN FLOW FROM THE
SOUTHEAST ALONG WITH INCREASING MID-HIGH LEVEL MOISTURE FROM THE WSW
SHOULD BRING AN INCREASE IN CLOUDS THROUGH FRIDAY NIGHT. TEMPS ABOUT
A CATEGORY BELOW NORMAL.

FOR SATURDAY THROUGH MONDAY: HIGH DEGREE OF FORECAST UNCERTAINTY AS
THE GFS/ECMWF BEGIN TO DIFFER CONSIDERABLY REGARDING THE CENTRAL US
TROUGH. BOTH INDICATE A POSITIVE TILT TO THE TROUGH ON SATURDAY...
BUT THE ECMWF EVOLVES INTO A SPLIT FLOW WITH A MORE AMPLIFIED AND
SLOWER WAVE THROUGH THE PLAINS COMPARED TO THE GFS. THE ECMWF THEN
DEVELOPS THIS INTO A CLOSED LOW TO OUR NORTH WITH A TROUGH COVERING
THE EASTERN CONUS SATURDAY NIGHT THROUGH MONDAY... WHILE THE GFS
TAKES THE WEAKER WAVE SWIFTLY OFFSHORE SUNDAY WITH MID LEVEL RIDGING
BUILDING OVER THE EASTERN CONUS BY MONDAY. RECENT GFS RUNS HAVE BEEN
TRENDING MORE AMPLIFIED AND SLOWER WITH THE WAVE... AND IT MAY BE
TOO EASILY KEEPING THE STREAMS PHASED... SO A LEAN TOWARD THE ECMWF
IS PREFERRED. THIS WILL MEAN A SLOWLY APPROACHING TROUGH FROM THE
WEST THROUGH MONDAY... RESULTING IN RAIN CHANCES FROM SATURDAY NIGHT
INTO MONDAY. THE OFFSHORE-DRIFTING SURFACE HIGH MAY DEPOSIT ENOUGH
COOL AIR IN THE PIEDMONT FOR AN IN SITU DAMMING EVENT. WILL LEAVE
TEMPS BELOW NORMAL THROUGH THE PERIOD... WITH SOME REBOUND IN TEMPS
MONDAY AS AN EDGE BACK TOWARD CLIMATOLOGY WITH A POSSIBLE WEAKENING
OF ANY WEDGE AIR MASS. -GIH

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 140 AM TUESDAY...

SFC WINDS...CURRENTLY NE SUSTAINED 10KTS WITH GUSTS 16-19KTS WILL
SUBSIDE AND BECOME NLY BY DAYBREAK. BY LATE LATE MORNING INTO THE
AFTERNOON...SFC WINDS WILL BECOME LIGHT AND VARIABLE.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...WSS
NEAR TERM...KC/SMITH
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...WSS

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

738 PM EDT WED APR 24 2013

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT. THE
HIGH WILL MOVE EAST ON THURSDAY AS A WEAK COLD FRONT MOVES ACROSS
THE AREA. THIS FRONT WILL BE FOLLOWED BY ANOTHER HIGH PRESSURE
SYSTEM THURSDAY NIGHT INTO FRIDAY. TEMPERATURES WILL REMAIN BELOW
NORMAL THROUGH THE PERIOD.

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
MODELS WERE IN FAIRLY DECENT AGREEMENT. HAVE USED A BLEND OF THE
GFS...NAM AND RAP FOR THE NEAR TERM FORECAST.

COLD FRONT WAS EAST OF THE FORECAST AREA THIS AFTERNOON. CLOUDS
CONTINUE TO LINGER AS WELL AS A FEW SHOWERS ACRS THE NRN ZONES. A
RIDGE OF HIGH PRESSURE TO OUR WEST IS EXPECTED TO BUILD EAST INTO
THE REGION TONIGHT. THIS WILL ALLOW SKIES TO CLEAR FROM WEST TO
EAST AS WELL AS ALLOW WINDS TO DIMINISH. THERE IS CONCERN FOR
FROST AND/OR FREEZING TEMPERATURES OVERNIGHT. CONCERNING FROST
FORMATION...THE BEST CHANCES WILL BE IN THE EASTERN/SOUTHERN ZONES
WHERE WINDS WILL BE THE LIGHTEST THE LONGEST AND SHOULD NOT BE
AFFECTED BY A LATE INCREASE IN WIND FROM THE WEST AS A WEAK COLD
FRONT APPROACHES. THE FAR NW HAS THE LEAST POTENTIAL FOR FROST DUE
TO THE INCREASING PRESSURE GRADIENT LATE AS THE HIGH DEPARTS TO
THE EAST AND AFOREMENTIONED WEAK COLD FRONT APPROACHES. HOWEVER...
THERE COULD BE A SHORT WINDOW FOR FROST FORMATION...ESPECIALLY IN
LOW LYING...SHELTERED LOCATIONS SO HAVE INCLUDED FROST HERE AS
WELL. AS FOR FROST AND FREEZING TEMPERATURES...IT LOOKS LIKE A
GOOD PORTION OF CENTRAL OHIO WILL HAVE THE HIGHEST THREAT OF
REACHING FREEZING OR FALLING SLIGHTLY BELOW. IN SUMMARY...A
FREEZING WARNING HAS BEEN POSTED FOR MUCH OF CENTRAL OHIO
(INCLUDING HARDIN COUNTY) WHILE A FROST ADVISORY HAS BEEN ISSUED
ELSEWHERE. GIVEN RECENT RAINFALL...THERE COULD BE SOME FOG
DEVELOPMENT IN THE ERN/SRN LOCATIONS OVERNIGHT...BUT CONFIDENCE IN
POTENTIAL PUBLIC IMPACT IS LOW AT THIS POINT AND HAVE LEFT OUT
ATTM. OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER TO MID 30S
WITH A FEW UPPER 20S POSSIBLE ACROSS PARTS OF CENTRAL OHIO.

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
RIDGE OF HIGH PRESSURE WILL MOVE EAST ON THURSDAY AS WEAK LOW
PRESSURE AND A COLD FRONT MOVE ACROSS THE GREAT LAKES AND OHIO
VALLEY. DEEPEST MOISTURE AND BEST LIFT ARE EXPECTED OVER THE NRN
ZONES AND HAVE CARRIED A CHANCE OF SHOWERS MAINLY ALONG AND NORTH
OF I-70. ELSEWHERE...SKIES WILL BE PARTLY SUNNY. TEMPERATURES WILL
BE TRICKY GIVEN SOME AFTERNOON CAA BEHIND THE FRONT AND CLOUD
DEVELOPMENT. WILL RANGE HIGHS FROM THE LOWER 50S NORTHWEST TO THE
LOWER 60S ALONG AND SOUTH OF THE OHIO RIVER.

WEAK WEATHER SYSTEM WILL PUSH EAST BY THURSDAY NIGHT...ALLOWING
ANOTHER AREA OF HIGH PRESSURE TO BUILD INTO THE REGION. SKIES WILL
CLEAR AND WINDS WILL DIMINISH. IT LOOKS LIKE A FAVORABLE NIGHT FOR
FROST FORMATION SO HAVE INCLUDED THIS WORDING IN THE FORECAST AND
HAVE MADE A MENTION OF IT IN THE HWO PRODUCT. OVERNIGHT LOWS WILL
BE IN THE LOWER TO MID 30S.

FOR FRIDAY INTO FRIDAY NIGHT...HIGH PRESSURE WILL CONTINUE TO
INFLUENCE THE REGION. RETURN SFC FLOW IS THE BEST ACROSS THE WEST
AND WEAKEST ELSEWHERE. ALSO...DESPITE SUNSHINE...850 MB TEMPS
APPEAR TO WARM UP MORE SLOWLY. AS A RESULT...HAVE GONE COOLER THAN
MOS GUIDANCE AS IT APPEARS TO BE WARMING THINGS UP A LITTLE TOO
MUCH. SOME CLOUDS WILL INCREASE LATER FRIDAY INTO FRIDAY NIGHT
FROM A MID LVL TROUGH TO OUR WEST...OTHERWISE DRY CONDITIONS ARE
EXPECTED.

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL BE DEPARTING THE CWA AT THE START OF THE
EXTENDED FORECAST PERIOD. MODEL AGREEMENT IS RELATIVELY POOR IN
HANDLING THE EVOLUTION OF A SLOW-MOVING MID-LEVEL TROUGH OVER THE
WEEKEND. EVEN AT 72HR ON THE 12Z GFSE...THERE IS SIGNIFICANT SPREAD
BETWEEN THE ENSEMBLE MEMBERS ON THE STRENGTH AND PLACEMENT OF THE
TROUGH. THE OPERATIONAL GFS SEEMS TO BE STRONGER WITH THE TROUGH
THAN MOST OF ITS MEMBERS...WHILE THE OPERATIONAL 12Z ECMWF IS A BIT
CLOSER TO THE GFSE MEAN.

LEANING TOWARD THE SLIGHTLY WEAKER SOLUTION WOULD PROVIDE LESS IN
THE WAY OF PRECIPITATION THAN THE OPERATIONAL GFS INDICATES.
THUS...THE FORECAST WILL START DRY...AND POPS WILL GENERALLY BE HELD
IN THE 20-40 CATEGORY AND NO HIGHER (THOUGH IT WILL BE WETTER
FURTHER SOUTH IN THE TENNESSEE VALLEY). THE HIGHEST POPS WERE
ROUGHLY TIMED TO THE DIURNAL CYCLE.

BY MONDAY...THE AXIS OF THE TROUGH WILL BE MOVING EAST OF THE
REGION...AS A BIG CHANGE TO THE WEATHER PATTERN BEGINS. THERE IS
SOME DEGREE OF AGREEMENT REGARDING THE LARGE-SCALE EVOLUTION NEXT
WEEK...WITH SIGNS OF HIGHLY-AMPLIFIED HIGH PRESSURE DEVELOPING FROM
THE DEEP SOUTH THROUGH THE OHIO VALLEY AND INTO ONTARIO. IN
FACT...BY THE VERY END OF THE EXTENDED FORECAST (AND INTO LATE WEEK)
BOTH 12Z OPERATIONAL RUNS (GFS/ECMWF) AND THE 00Z ECMWF SHOW A
FULL-OUT OMEGA BLOCK DEVELOPING (TROUGH IN THE CENTRAL PLAINS /
RIDGE THROUGH THE EASTERN STATES / TROUGH OVER THE ATLANTIC). WITH
THIS AGREEMENT...THE 12Z CMC (WHICH DEVELOPS A CLOSED LOW OVER THE
DEEP SOUTH ON TUESDAY) WAS NOT USED FOR THE FORECAST.

THROUGH THE FIRST PART OF THE WEEK...DIURNALLY-DRIVEN POPS WERE
MAINTAINED (THOUGH GRADUALLY DECREASING EACH DAY AS THE RIDGE
BUILDS). SIGNIFICANT PRECIPITATION APPEARS TO REMAIN WEST OF THE ILN
CWA THROUGH AT LEAST WEDNESDAY. TEMPERATURES APPEAR TO SLOWLY RISE
THROUGH THIS PERIOD AS WELL...WITH NO SIGNIFICANT DIFFERENCES
OBSERVED IN THE RECENT MODEL RUNS (AND ONLY SMALL CHANGES MADE TO
THE GOING FORECAST). WITH THE ILN CWA LOOKING TO BE ON THE WEST SIDE
OF THE BUILDING RIDGE (AND ASSOCIATED SURFACE HIGH)...SUCH A PATTERN
WILL FAVOR SOUTHERLY FLOW.

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
SOME PASSING VFR SHOWERS MAY BRING A QUICK DROP TO MVFR CIG BUT
NOT FOR MORE THAN A FEW MINUTES IN THE NEXT TWO HOURS OVER THE TAF
SITES. NORTHWEST WINDS WILL LOSE THE GUSTINESS AND BECOME MORE
SOUTHWESTERLY OVERNIGHT AND LIGHTEN. SOME MORNING MIST IS EXPECTED
TO REDUCE VSBYS TO 4-5 SM ON AVERAGE ACROSS THE REGION DUE TO THE
RAIN WE RECEIVED TODAY. SKIES WILL CU DURING THE AFTERNOON AND
WILL LIKELY CONSTITUTE A BKN-OVC DECK ALONG AND JUST SOUTH OF THE
I-70 CORRIDOR. A PASSING SPRINKLE/SHOWER COULD DIP CIGS TOWARDS
3KFT IN DAY/CMH/LCK BUT THIS IS MORE LIKELY EARLIER IN THE
AFTERNOON TOWARDS KDAY WHEN THE STRONGEST LIFT DUE TO THE MID
LEVEL VORT MAX WILL OCCUR. AFTERNOON GUSTS TO 20-25KT WILL BE
FOUND WITH SOME SUSTAINED WINDS AT 14-16KT TO THE NORTH.

WINDS WILL LIGHTEN AND SKY COVER DRASTICALLY DROP WITH THE SETTING
SUN TOMORROW EVENING.

OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR OHZ034-035-
042>044-051>053-060>063-070>073-077>082-088.
FREEZE WARNING FROM 2 AM TO 9 AM EDT THURSDAY FOR OHZ026-045-
046-054>056-064-065-074.
KY...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR KYZ089>100.
IN...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR INZ050-058-
059-066-073>075-080.

$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...HATZOS
AVIATION...FRANKS

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

147 PM EDT TUE APR 23 2013

.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO SLIDE EAST EARLY TODAY. A COLD
FRONT WILL APPROACH LATER TODAY AND THEN PUSH THROUGH THE AREA
TONIGHT AND WEDNESDAY. SHOWERS WILL ACCOMPANY THE FRONT FOLLOWED
BY ANOTHER PERIOD OF COOLER TEMPERATURES FOR THE LATTER HALF OF
THE WORK WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW AMPLITUDE MID LEVEL RIDGE IS LOCATED OVER THE SOUTHEAST US
TODAY WITH A BROAD TROUGH IN THE NATIONS MID SECTION. SURFACE HIGH
PRESSURE IS CENTERED NEAR NEW ENGLAND WITH A COLD FRONT
APPROACHING FROM THE MS VALLEY. CLOUDS HAVE BEGUN ENCROACHING
FROM THE WEST THIS MORNING...MAINLY IN THE FORM OF THIN CIRRUS.
THESE CLOUDS WILL CONTINUE TO THICKEN AND LOWER THROUGH THE DAY.
SATELLITE IMAGERY AND WEBCAMS SUGGEST A FAIRLY OPAQUE SKY IN
WESTERN INDIANA SO I HAVE SIGNIFICANTLY INCREASED CLOUD COVER
TODAY NORTHWEST OF I-71 AS THESE CLOUDS ADVECT IN. INCREASING
SOUTHERLY FLOW WILL HELP OFFSET THE CLOUD COVER AS GUSTS WILL
APPROACH 20-25 KT THIS AFTERNOON. THEREFORE HAVE KEPT HIGH
TEMPERATURES THE SAME IN THE NW...WITH A SLIGHT BUMP UP IN THE SE
(SOME MID 70S EXPECTED) BASED ON CURRENT TRENDS AND PERHAPS A BIT
MORE SUN.

REGARDING PRECIPITATION CHANCES...MODIFIED THE POP FORECAST TO
MIRROR MORE CLOSELY THE RUNS OF HIGH RESOLUTION MODELS...WHICH ARE
PRETTY CONSISTENT IN BRINGING AN INITIAL SHOT OF MOISTURE AND
LIFT TO THE NORTHERN WHITEWATER AND MIAMI VALLEYS THIS AFTERNOON
(MAINLY IN 21-00Z TIME FRAME). HAVE ADDED THUNDER TO THE FORECAST
PER INSTABILITY IN NAM AND RAP FORECAST SOUNDINGS. HOWEVER WITH
POOR SOLAR INSOLATION AND MEAGER CAPE (WHICH MAY BE ELEVATED)...DO
NOT EXPECT ROBUST ENOUGH UPDRAFTS TO BE ABLE TO TAP INTO THE
MODERATE SHEAR THAT IS IN PLACE...SO STRONG STORMS ARE NOT
EXPECTED AT THIS TIME. THE MODELS DIFFER ON WHETHER THERE WILL BE
A BREAK BETWEEN THIS INITIAL ACTIVITY AND THE MAIN FRONTAL BAND
ACROSS WEST CENTRAL OHIO...SO JUST DEPICTED A FAIRLY SMOOTH BLEND
INTO THE PREVIOUS FORECAST.

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE COLD FRONT WILL PUSH INTO INDIANA THIS EVENING...THEN INTO
OHIO BY WEDNESDAY MORNING. SHOWERS WILL BECOME WIDESPREAD LATE
TONIGHT AS MOISTURE IS TRANSPORTED ALONG THE FRONT ON A STRONG
SOUTHWESTERLY FLOW ALOFT. THOUGH SURFACE BASED INSTABILITY WILL BE
LACKING DURING THE OVERNIGHT PERIOD...THERE WILL BE ENOUGH
ELEVATED CAPE TO PRODUCE ISOLATED THUNDERSTORMS. CURRENT
INDICATIONS ARE THAT AROUND A HALF AN INCH OF RAIN WILL OCCUR WITH
THE RATHER MOIST BUT FAST MOVING FRONT.

AS THE FRONT CONTINUES ITS EASTWARD PROGRESS...SHOWERS WILL
LINGER INTO WEDNESDAY BEFORE ENDING FROM WEST TO EAST WEDNESDAY
AFTERNOON. A BRIEF DRY PERIOD IS SUGGESTED FOR WEDNESDAY EVENING
BEFORE A DISTURBANCE MOVING THROUGH THE GREAT LAKES BRINGS A
CHANCE FOR RAIN AND SNOW SHOWERS TO NORTHERN LOCATIONS LATE
WEDNESDAY NIGHT INTO EARLY THURSDAY.

TEMPERATURES WILL BE MUCH COOLER BEHIND THE FRONT WITH HIGHS
AROUND 50 ON WEDNESDAY AND IN THE MID 50S ON THURSDAY. WITH
EXPECTED LOWS IN THE MID 30S WEDNESDAY NIGHT...FROST MAY
FORM...BUT ITS OCCURRENCE MAY BE LIMITED BY CLOUDS AND WINDS.

.LONG TERM /THURSDAY THROUGH MONDAY/...
HIGH PRESSURE WILL MOVE ACROSS THE REGION THURSDAY NIGHT THROUGH
FRIDAY NIGHT. TEMPERATURES WILL BE BELOW NORMAL DURING THIS PERIOD
WITH SOME FROST NOT OUT OF THE QUESTION THURSDAY NIGHT.

12Z MODELS CONTINUE TO SHOW VARYING SOLUTIONS FOR THE WEEKEND INTO
THE BEGINNING OF NEXT WEEK. WPC PREFERENCE LEANS TOWARDS SLOWER
ECMWF BASED ON FLOW EVOLUTION UPSTREAM AND HAVE FOLLOWED ALONG WITH
THAT THINKING. THIS WILL LEAD TO UNSETTLED CONDITIONS FOR SATURDAY
THROUGH MONDAY AS A MID LEVEL TROUGH GETS BLOCKED FROM PROGRESSING
EAST AND MAY EVEN CLOSE OFF FOR A TIME. AT THIS POINT GREATER
CHANCES OF RAIN APPEAR TO BE OVER THE WEEKEND. CLOUDS AND
PRECIPITATION POTENTIAL SHOULD NARROW THE DAILY DIURNAL RANGE WITH
LOWS AVERAGING ABOVE NORMAL AND HIGH REMAINING BELOW NORMAL.

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR MID/HIGH CLOUDS WILL CONTINUE TO THICKEN THIS AFTERNOON INTO
THE EVENING. THESE MAY BE HELPING TO KEEP WIND GUSTS DOWN AT THE
MOMENT BUT STILL EXPECT A FEW HOURS OF SOUTHERLY GUSTS OF 20-25 KT
DURING PEAK MIXING THIS AFTERNOON. AS MOISTURE AND LIFT INCREASE
LATE THIS AFTERNOON...A FEW SHOWERS MAY DEVELOP FROM WEST CENTRAL
INTO NORTH CENTRAL OHIO...CLOSE ENOUGH TO THE DAYTON AND COLUMBUS
SITES TO HAVE A FEW HOURS OF VCSH.

THE MAIN PERIOD OF AVIATION INTEREST WILL BE A COLD FRONTAL
PASSAGE LATE TONIGHT AND WEDNESDAY MORNING. VARIOUS COMPUTER MODEL
SOLUTIONS CONTINUE TO DIFFER WITH THE EXACT TIMING OF THE FRONTAL
PASSAGE. PUSHED TIMING BACK SLIGHTLY BUT MAINTAINED WX CONSISTENCY
WITH PREVIOUS FORECAST AND FIRST BROUGHT IN A VCTS ALONG THE
LEADING EDGE OF PRECIPITATION WHERE THERE WILL BE SOME LIMITED
INSTABILITY. NEAR AND JUST BEHIND THE FRONT...CEILINGS WILL LOWER
INTO THE MVFR RANGE AND BE ACCOMPANIED BY A PERIOD OF PREVAILING
RAIN SHOWERS AND MVFR VISIBILITY. WINDS WILL SHIFT FROM SOUTH TO
WNW WHILE MAINTAINING 10-15 KT SPEEDS. HAVE FRONTAL PASSAGE ACROSS
THE AREA BETWEEN 08-12Z. THE BACK EDGE OF PRECIPITATION WILL BEGIN
WORKING THROUGH THE TAF SITES AFTER 16Z.

OUTLOOK...MVFR CEILINGS AND VISIBILITIES POSSIBLE WEDNESDAY.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...SNYDER
SHORT TERM...CONIGLIO
LONG TERM...
AVIATION...SNYDER

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

1042 AM EDT TUE APR 23 2013

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
HIGH CLOUDS WILL BE ON THE INCREASE THIS MORNING IN THE WAA PATTERN
AHEAD OF AN APPROACHING COLD FRONT. EXCEPT FOR SOME EARLY MVFR
VSBY RESTRICTIONS DUE TO FOG AT KLUK...VFR CONDITIONS WILL PERSIST
THRU THE MORNING. AHEAD OF THE FRONT...THE PRESSURE GRADIENT WILL
TIGHTEN THROUGH THE DAY...LEADING TO AN INCREASE IN SOUTHERLY
WINDS WITH WIND GUSTS UP TO 25 KTS. CLOUDS WILL SLOWLY LOWER WITH
MID LEVEL CIGS DEVELOPING TOWARD EVENING. A FEW SCTD TO ISOLD
SHOWERS WILL BE PSBL DURG THE AFTN WITH THE BEST CHANCE ACRS KDAY
AND HAVE A MENTION OF VCSH TO ACCOUNT FOR THIS INITIAL LIMITED
COVERAGE. WIDESPREAD PCPN WILL DEVELOP TONIGHT WITH THE BULK OF
THE SHOWERS ASSOCIATED WITH THE FRONTAL PASSAGE AFTER 06Z. EXPECT
SOME EMBEDDED THUNDER DURG THE LATE EVENING BUT DUE TO LIMITED
COVERAGE HAVE LIMITED THUNDER MENTION MENTION TO VCTS. HAVE
PREVAILING RAIN SHOWERS DEVELOPING AT ALL TAF SITES BETWEEN 07Z
AND 08Z WITH MVFR CIGS AND VSBYS DEVELOPING. SRLY WINDS WILL SHIFT
TO THE NW LATE TONIGHT WITH THE FRONTAL PASSAGE AND CONTINUE FROM
THE NW AT 10 TO 15 KTS.

OUTLOOK...MVFR CEILINGS AND VISIBILITIES POSSIBLE WEDNESDAY.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...SNYDER
SHORT TERM...CONIGLIO
LONG TERM...
AVIATION...AR

AREA FORECAST DISCUSSION

NWS SIOUX FALLS SD

312 PM CDT TUE APR 23 2013

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 254 PM CDT TUE APR 23 2013

CLEAR SKIES ARE EXPECTED TO CONTINUE THROUGH THE EVENING HOURS
TONIGHT AS SURFACE HIGH PRESSURE BUILDS INTO THE AREA. WINDS ON THE
SURFACE WILL TURN WEST TO SOUTHWEST OVERNIGHT...THOUGH THE PRESSURE
GRADIENT DOESN`T BECOME ALL THAT LIGHT. AS SUCH...HAVE NUDGED
FORECAST LOWS UPWARD EVER SO SLIGHTLY...WITH WARMEST READINGS IN
MOST EXPOSED LOCATIONS. NAM FORECAST SOUNDINGS INDICATE POTENTIAL
FOR FOG...BUT THIS IS NOT SUPPORTED BY THE RAP SOUNDINGS. HRRR IS
DOWN FOR MAINTENANCE...BUT IN GENERAL...THINK THE WINDS WILL STAY UP
ENOUGH TONIGHT THAT FOG WILL NOT BE THAT BIG OF A CONCERN.

SHORTWAVE DROPS SOUTHEAST ACROSS THE REGION ON WEDNESDAY. MODELS
SUGGEST THAT SOME OF THE INITIAL DYNAMICS WILL BE LOST TO SATURATING
THE NEAR SURFACE LAYER. TOUGH CALL ON PRECIPITATION TYPE WHICH WILL
BE CONTROLLED BY SURFACE TEMPERATURES AS THIS IS THE ONLY LOCATION
IN THE THERMO PROFILE THAT IS POTENTIALLY ABOVE FREEZING. HAVE A
MIX OF SNOW AND RAIN ALONG THE HIGHWAY 14 CORRIDOR IN THE LAT
MORNING INTO THE EARLY AFTERNOON...BUT IN GENERAL PRECIPITATION
SHOULD PRIMARILY FAVOR RAIN WHICH IS SUPPORTED BY SREF PROFILES.
PROFILES ARE WEAKLY UNSTABLE ALOFT...AND GIVEN THIS IS THE
CASE...THE POTENTIAL EXISTS FOR RAIN OR SNOW SHOWERS TO DEVELOP IN
THE AFTERNOON HOURS. IF THE INTENSITY WAS TO GET STRONG
ENOUGH...THEN MAY BE ABLE TO GET BRIEF SNOW SQUALLS IN HIGHER
INTENSITY PRECIPITATION BANDS. IN GENERAL...EXPECT PRECIPITATION
AMOUNTS TO BE FAIRLY LIGHT...WITH A FEW HUNDREDTHS OF AN INCH OR
LESS IN MOST LOCATIONS. APPEARS TO BE QUITE BREEZY WITH 20-30 KNOTS
OF FLOW AT 925 HPA COMBINED WITH LOW LEFT COLD AIR ADVECTION AIDING
IN MIXING.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 254 PM CDT TUE APR 23 2013

THE TAIL END OF THE WAVE WILL BE MOVING THROUGH EARLY ON WEDNESDAY
EVENING MAY ALLOW FOR A FEW STRAGGLING SHOWERS IN THE FAR EASTERN
CWA...OTHERWISE CLEARING SKIES AND LIGHTER WINDS SHOULD ALLOW FOR
A COOL NIGHT AS NORTHWEST WINDS RELAX TO WEST AND SOUTHWEST. LOWS
SHOULD MAINLY BE IN THE 20S WITH A FEW TEENS POSSIBLE AREAS WITH
DEEPER SNOW COVER.

THURSDAY WILL PROVE TO BE A DECENT SNOW MELTING DAY WITH MOSTLY
SUNNY TO PARTLY CLOUD CONDITIONS AND MILDER READINGS. LOW LEVEL
WIND DIRECTION AND THE LOCATION OF THE INCOMING WARM FRONT WILL
PLAY A BIG ROLE ON WHERE THE BEST WARMING WILL BE. WILL AIM FOR
THE WARMEST READINGS WEST OF THE JAMES RIVER VALLEY WHERE THE BEST
CHANCE RESIDES OF WINDS BECOMING SOUTH OR SLIGHTLY SOUTHWEST. THE
FARTHER EAST FROM HERE THE BETTER CHANCE THAT A SOUTHEAST
COMPONENT WILL HANG IN. WILL HAVE HIGHS RANGING FROM 60 TO 65 WEST
OF THE JAMES TO AROUND 50 NORTH AND EAST OF A BROOKINGS TO JACKSON
LINE.

THURSDAY NIGHT INTO FRIDAY WILL SEE A SOUTHERLY WIND TURNS A BIT
SOUTHWEST WHICH WILL BRING THE PROBABILITY FOR MUCH WARMER
READINGS AND LIKELY THE FINAL DAY WITH ANY REAL SNOW COVER LEFT ON
THE GROUND. NOT PLANNING ON THE SNOW COVER HAVING MUCH OF AN
EFFECT SO WILL GO WITH HIGHS MAINLY IN THE 60S.

THE BIG WARM UP IS STILL ON TAP THIS WEEKEND AND WILL CONTINUE TO
KEEP ABOVE NORMAL TEMPERATURES GOING. THE MAIN DIFFERENCES IN THE
MODELS SHOW UP AROUND MONDAY WHERE THE GFS DIVES COLDER AIR SOUTH
AS A FAIRLY STRONG TROUGH MOVES THROUGH NORTH DAKOTA. THE ECMWF
AND THE EXTRAPOLATED GEM ARE LESS BOISTEROUS WITH THIS WAVE AND
MORE OR LESS RIDE THE ENERGY ALONG AND NORTH OF THE PERIPHERY OF
THE RIDGE...KEEPING THE WARM AIR IN PLACE THROUGH TUESDAY. WILL
STICK CLOSEST TO THE GEM/ECMWF OUTPUT WHICH SEEMS MORE REASONABLE
AND THE GFS IS LIKELY PUSHING THE TROUGH TO AGGRESSIVELY THROUGH
THE EXISTING RIDGE. NOT PLANNING ON ANY REAL ISSUES WITH
PRECIPITATION DURING THIS TIME FRAME.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1223 PM CDT TUE APR 23 2013

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. SURFACE HIGH
PRESSURE WILL BUILD INTO THE AREA OVERNIGHT LEADING TO LIGHT
WINDS. MODEL SOUNDINGS SUGGEST THE POTENTIAL FOR FOG...BUT DID NOT
INCLUDE MENTION WITH ONLY LIMITED SNOW MELT EXPECTED TODAY.
SOUTHWEST WINDS INCREASE AHEAD OF NEXT WAVE DROPPING DOWN IN
NORTHWEST FLOW. PRECIPITATION IS EXPECTED TO DEVELOP AROUND KHON
AROUND 18Z...SPREADING SOUTHEAST THROUGH THE AFTERNOON.

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

SHORT TERM...
LONG TERM...08
AVIATION...

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY

NWS RAPID CITY SD

517 AM MDT TUE APR 23 2013

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
ISSUED AT 341 AM MDT TUE APR 23 2013

CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER THE
SOUTHERN PLAINS...WITH HIGH PRESSURE GENERALLY OVER THE NORTHERN
HIGH PLAINS. UPPER LEVEL ANALYSIS SHOWS TROF STRETCHING FROM THE
UPPER MIDWEST INTO THE CENTRAL PLAINS AND CENTRAL ROCKIES. SKIES
HAVE BECOME MAINLY CLEAR ACROSS MUCH OF THE AREA...EXCEPT FOR SOME
LINGERING LOW CLOUDS ACROSS THE BLACK HILLS AREA INTO SOUTHWESTERN
SD. TEMPS HAVE DROPPED INTO THE TEENS ACROSS MUCH OF THE AREA...WITH
SOME SINGLE DIGITS OVER THE BLACK HILLS. WINDS ARE LIGHT FROM THE
WEST TO NORTHWEST IN MOST AREAS.

COOLER WEATHER WILL PERSIST ACROSS THE AREA FOR A COUPLE OF MORE
DAYS BEFORE A SIGNIFICANT WARMUP TAKES PLACE DURING THE LATTER HALF
OF THE WEEK AND THE WEEKEND. FOR TODAY...SKIES WILL BE MAINLY SUNNY.
SOME ISOLATED TO SCATTERED CUMULUS WILL LIKELY DEVELOP IN SPOTS TO
THE SOUTH AND EAST OF THE BLACK HILLS BY THE AFTERNOON...WITH SOME
INCREASING HIGH CLOUDS ACROSS NORTHERN AND WESTERN AREAS DURING THE
AFTERNOON. HIGHS WILL BE IN THE 30S AND LOWER 40S... GENERALLY
WARMEST ACROSS SNOWCOVER FREE AREAS OF FAR NORTHWESTERN SD. WEST TO
NORTHWEST WINDS WILL PERSIST ACROSS THE AREA...INCREASING A BIT
DURING THE LATE MORNING AND AFTERNOON.

CLOUDS WILL CONTINUE TO INCREASE TONIGHT AND LOWER AS CANADIAN COLD
FRONT APPROACHES. THE FRONT WILL MOVE THROUGH NORTHERN AND WESTERN
PORTIONS OF THE CWA LATE TONIGHT AND ACROSS THE REST OF THE FORECAST
AREA DURING THE MORNING. CHANCES FOR SNOW SHOWERS WILL INCREASE
ACROSS FAR NORTHEASTERN WY...THE NORTHERN BLACK HILLS...AND MUCH OF
NORTHWESTERN SD AFTER MIDNIGHT AND ESPECIALLY TOWARD MORNING AS
FRONT MOVES THROUGH. THE BEST UPPER LEVEL SUPPORT WITH THIS FRONT IS
LIKELY TO MOVE THROUGH JUST BEHIND THE COLD FRONT DURING THE MORNING
AND MIDDAY HOURS. WILL KEEP CHANCES FOR SHOWERS ACROSS THE
AREA...MOSTLY SNOW IN THE MORNING AND THEN A MIX TO RAIN INTO THE
AFTERNOON. THE BEST CHANCES FOR PCPN WILL BE ACROSS THE NORTHERN
BLACK HILLS...WHERE BETTER MOISTURE AND UPSLOPE FLOW WILL LIKELY
PRODUCE SOME LIGHT ACCUMULATIONS OF SNOW LATE TONIGHT INTO
WEDNESDAY. ACCUMULATIONS THERE LOOK TO BE UP TO 2 INCHES OR SO LATE
TONIGHT AND WEDNESDAY. ELSEWHERE...ANY ACCUMULATIONS SHOULD
GENERALLY BE LESS THAN AN INCH LATE TONIGHT INTO WEDNESDAY MORNING.
SHOWERS WILL DISSIPATE LATE IN THE DAY AS WAVE PUSHES QUICKLY
SOUTHEAST OF THE AREA.

THE OTHER FORECAST CONCERN WITH THIS SYSTEM WILL BE WINDS. THEY WILL
INCREASE IN THE MORNING BEHIND THE FRONT AND PERSIST THROUGH THE
AFTERNOON. THE STRONGEST WINDS ALOFT WILL MOVE ACROSS NORTHWESTERN
INTO CENTRAL SD DURING THE MORNING. THIS WOULD SUGGEST THE STRONGEST
WINDS WILL BE FOR A BRIEF PERIOD BEHIND THE FRONT. WINDS AT THIS
POINT LOOK TO BE IN THE LOW END ADVISORY CRITERIA FOR AT LEAST A
COUPLE OF HOURS IN THE MORNING TO MIDDAY HOURS ACROSS A GOOD PORTION
OF THE NORTHWEST AND WEST CENTRAL SD PLAINS. WINDS SHOULD QUICKLY
DIMINISH LATE IN THE DAY AND EARLY EVENING AS MIXING CEASES.

.LONG TERM...THURSDAY THROUGH MONDAY
ISSUED AT 341 AM MDT TUE APR 23 2013

PERSISTENT HIGH HEIGHTS OVER THE EASTERN PAC AND FAR
WESTERN NOAM WILL RETROGRADE WEST IN THE PERIOD...WITH A DOWNSTREAM
PATTERN CHANGE EXPECTED TO EVOLVE AS WESTERN ATLANTIC RIDGE BLOCKING
WILL DIMINISH. THIS WILL LEAD TO GRADUAL LOWER HEIGHTS OVER THE
EASTERN PAC AND FAR WESTERN NOAM...SETTING THE STAGE FOR MUCH WARMER
WEATHER INTO THE LOCAL REGION. PROGRESSIVE FAST FLOW LOOKS TO REMAIN
IN PLACE OVER SOUTHERN CANADA...SUPPORTING A SEMI ZONAL FLOW
INTO THE REGION. THE DEGREE OF TROUGHING IN THE NW CONUS AND THE
POSITION OF THIS FEATURE WILL HAVE AN IMPACT ON THE DEGREE OF LOCAL
WARMING AS WELL AS ITS DURATION. THE 00Z ECMWF IS CERTAINLY THE
FARTHEST WEST BIAS PER THIS FEATURE WHEN COMPARED THE GFS/GEFS/AND
NAEFS. IT ALSO DEVELOPS A STAUNCH OMEGA BLOCK EXTENDING NORTH INTO
THE BERING SEA...WITH THE GFS/GEFS/AND NAEFS SETTLING FOR SPLIT FLOW
PER THIS FEATURE...ALLOWING TROUGHING TO PROGRESS FARTHER EAST EARLY
NEXT WEEK. THE OUTCOME OF THIS EVOLUTION WILL HAVE AN IMPACT ON
PRECIP CHANCES AND TEMPS TOWARD THE END OF THE PERIOD AND BEYOND.

MAIN FEATURE IN THE PERIOD IS THE EXPECTED WARMING TREND THROUGH THE
WEEKEND. WAA ENSUES THUR AND WILL CONTINUE INTO THE WEEKEND. TEMPS
REMAIN QUITE TRICKY IN THE PERIOD...ESP EARLY ON WITH SIG SNOW PACK
IN PLACE ACROSS MUCH OF THE AREA. HOWEVER...MOSTLY SUNNY CONDITIONS
WITH THE WESTERLY DOWNSLOPE FLOW WILL CERTAINLY AID IN PUSHING TEMPS
UP...WITH A TREND TOWARD THE MIDDLE OF GUIDANCE FAVORED ATTM...ESP
AS SNOW WILL SIG MELT THE NEXT TWO DAYS WITH TEMPS IN THE 30S AND
40S UNDER STRONG APRIL SUN. WESTERN NOAM TROUGHING WILL DEVELOP WITH
AN ASSOCIATED LEAD IMPULSE EXPECTED TO ROUND THE TROUGH TOWARD THE
END OF THE WEEKEND SUPPORTING A SFC REFLECTION. THIS FEATURE WILL
PUSH INTO THE REGION SUNDAY-SUNDAY NIGHT AND SUPPORT LL THETA-E
RIDGING...POSSIBLY SUPPORTING A SHOWER OR TS OVER THE HIGH TERRAIN
OF NE WY OR THE BH THEN...WITH POSSIBLE SHOWERS ALONG AND AHEAD OF
THE SFC TROUGH SUNDAY NIGHT INTO MONDAY. THIS IS THE ONLY PRECIP
MENTION ATTM IN THE PERIOD...AND IS CONFINED TO THE NW ZONES.
OTHERWISE...CONTINUED SEASONAL TEMPS MONDAY...WITH A SLIGHT
DOWNTREND IN TEMPS PER A POSSIBLE COLD FRONTAL INFLUENCE.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 512 AM MDT TUE APR 23 2013

VFR CONDITIONS WILL CONTINUE THROUGH TODAY AS HIGH PRESSURE
COVERS THE REGION. A FAST MOVING UPPER TROUGH WILL SUPPORT
LOWERING CIGS ACROSS THE NORTHERN HALF OF THE FA LATE
TONIGHT...WITH POSSIBLE VIS RESTRICTIONS IN -SN. HAVE ADDED A
MVFR CIG MENTION AT GCC FOR THIS TREND. ATTM...PROB FOR
RESTRICTIONS AT RAP REMAIN LOW GIVEN NW FLOW AND BH DOWNSLOPE
EFFECTS.

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

SHORT TERM...26
LONG TERM...JC
AVIATION...JC

AREA FORECAST DISCUSSION

NWS LUBBOCK TX

1154 PM CDT MON APR 22 2013

.AVIATION...
STRONG COLD FRONT HAS PUSHED THROUGH BOTH TERMINALS. GUSTY WINDS
WILL PERSIST MUCH OF THE NIGHT AT BOTH TERMINALS WITH LOW CLOUDS
MAKING IT INTO BOTH SITES SHORTLY. BLOWING DUST WILL BE A CONCERN
AT BOTH SITES FOR A FEW HOURS BEHIND THE FRONT.
OTHERWISE...CONDITIONS IMPROVING LATE THIS MORNING.

SHORT TERM...
A STRONG COLD FRONT LOOKING TO BE A LITTLE AHEAD OF SCHEDULE HAVING
ALREADY NOSED INTO THE OKLAHOMA PANHANDLE AS OF 19Z...ALTHOUGH THE
COLD AIR LAGGING THE INITIAL WIND SHIFT BY ABOUT 150 TO 200 MILES.
MORNING RAP RUNS FASTEST WITH THE FRONT LOOK TO BE THE MODEL TO LEAN
TOWARD...AND POSSIBLY SLIGHTLY FASTER THAN THAT. WINDS WILL LIKELY
ACCELERATE TOWARD ADVISORY CRITERIA WITH PRESSURE RISES BEHIND IT...
ALTHOUGH FOR NOW WILL KEEP SPEEDS JUST BELOW THAT LEVEL. WILL RUN
WITH LOW TEMPS JUST BELOW LOW END OF MOS NUMBERS GIVEN STRENGTH OF
THE COLD AIR. THAT WOULD PUT POTENTIAL FOR A LIGHT FREEZE ACROSS THE
EXTREME SW PANHANDLE WHERE JUST NOW REACHING AVG DATE TO THE
BEGINNING OF THE GROWING SEASON. BETTER CANDIDATE FOR FREEZE PRODUCT
TO COME TUESDAY NIGHT WITH POTENTIAL FOR A HARD FREEZE. LOW CLOUDS
TO FILTER IN BEHIND THE FRONT. WHILE LOW CLOUDS PROGGED TO LIFT
TUESDAY MORNING...PERSISTENT MID LEVEL MOISTURE SHOULD KEEP SOME
CLOUD COVER OVER THE AREA. THAT COMBINED WITH LOW LEVEL COLD
ADVECTION THROUGH THE DAY WILL RESULT IN A DIURNAL RANGE OF 10 TO 15
DEGREES. OTHER ISSUE IS CHANCE FOR LIGHT PRECIP IN POST-FRONTAL AIR
MASS LATE TONIGHT AND EARLY TUESDAY. LOW LEVEL FRONTOGENESIS MAY BE
SUFFICIENT TO GENERATE SOME DRIZZLE OR VERY LIGHT RAIN ACROSS THE
NERN ZONES...BUT MEASURABLE PRECIP CHANCES LOOK VERY SLIM WITH BEST
LIFT ASSOCIATED WITH MID LEVEL TROUGH/JET REMAINING NORTH OF THE
FCST AREA. FINALLY...WHILE COLD FRONT WILL BE MOVING INTO AIR WITH
DEW POINTS IN THE 40S AND THUS SOME CAPE...CAP STRENGTH LOOKS TO BE
VERY STRONG WITH LITTLE POTENTIAL THAT ENERGY CAN BE RELEASED.

LONG TERM...
THE PRIMARY CONCERN FOR TUESDAY NIGHT AND WEDNESDAY MORNING WILL BE
THE POTENTIAL FOR A WIDESPREAD FREEZE ON THE HEELS OF THE PREVIOUS
NIGHTS FROPA. MODELS SEEM TO AGREE THAT H850 TEMPS WILL SETTLE
SOMEWHERE BETWEEN 0 TO -3 DEGREES... WITH THE NAM BEING THE COLD
OUTLIER OF THE BUNCH. IN ADDITION... A 1025-1030MB SURFACE RIDGE
WILL SLIDE JUST TO THE NE OF THE AREA OVERNIGHT...WHICH WILL KEEP
WINDS VERY LIGHT. ON THE OTHER HAND... SOME LINGERING JET ENERGY
AND MID-LEVEL MOISTURE COULD KEEP A BIT OF CLOUD COVER IN THE
AREA... INHIBITING RADIATIONAL COOLING IN SOME SPOTS... PARTICULARLY
IN THE EASTERN ZONES. REGARDLESS... CLOUD COVER SHOULD BREAK UP
BEFORE SUNRISE... AND TEMPERATURES ACROSS THE CAPROCK WILL LIKELY
FALL TO AROUND 4-8 DEGREES BELOW FREEZING BEFORE ALL IS SAID AND
DONE. TEMPERATURES WILL GRADUALLY RISE WEDNESDAY AND THURSDAY AHEAD
OF AN APPROACHING WAVE... WHICH WILL BE OUR NEXT ITEM OF CONCERN.

BY THURSDAY... A MEANDERING CLOSED LOW WILL WORK ITS WAY EASTWARD
FROM THE SUBTROPICAL PACIFIC BEFORE OPENING UP AND PHASING WITH A
BROAD CENTRAL CONUS TROUGH. BEFORE COMPLETELY BEING ABSORBED...
THIS WAVE WILL TRAVERSE THE TX PANHANDLE SOMETIME LATE THURSDAY
NIGHT... ALTHOUGH THERE IS STILL ABOUT 6 HOURS OF DISAGREEMENT
BETWEEN THE THE GFS AND ECMWF. AHEAD OF THIS WAVE... PRESSURE FALLS
ACROSS THE SOUTHERN FRONT RANGE WILL BEGIN TO FORCE SOUTHERLY FLOW
ACROSS TX...AND IN TURN ALLOW MODEST MOISTURE TO RETURN TO THE SOUTH
PLAINS AND EASTERN NM. DUE TO TUESDAYS COLD FRONT PINNING DEEP
MOISTURE WELL TO THE SOUTH... THE TIMING AND EXTENT OF THIS MOISTURE
RETURN IS IN QUESTION... AND AT THIS TIME IT APPEARS THAT THE BEST
MOISTURE WILL STRUGGLE TO ARRIVE UNTIL OVERNIGHT THURSDAY AND EVEN
EARLY FRIDAY MORNING. IN ADDITION... A STOUT CAP AND LOW-LEVEL
STRATUS WILL LIKELY ELIMINATE THE POSSIBILITY FOR AFTERNOON
THUNDERSTORM INITIATION EXCEPT FOR POSSIBLY ALONG THE
DRYLINE/PACIFIC FRONT IN EASTERN NM. AS THE WAVE PROGRESSES
EASTWARD... A PACIFIC FRONT WILL ALSO PUSH EASTWARD AND LIKELY
TRAVERSE THE AREA VERY LATE THURSDAY/EARLY FRIDAY...ALTHOUGH AGAIN
THE TIMING OF THIS FEATURE IS STILL SOMEWHAT IN QUESTION. AS THIS
FRONT MOVES EAST... IMPROVING MOISTURE ACROSS THE SOUTH PLAINS COULD
YIELD AT MARGINAL CHANCES FOR SHOWER/THUNDERSTORM
DEVELOPMENT...MOSTLY ACROSS THE NORTHERN ZONES WITH THE ADDED
FORCING FROM THE FRONT AND PASSING WAVE.

BEYOND FRIDAY MORNING... MODEL SOLUTIONS DIVERGE SIGNIFICANTLY...
ALTHOUGH THE GENERAL TREND WILL BE FOR BUILDING HEIGHTS AND WARMER
TEMPERATURES THROUGH THE END OF THE WEEK AND INTO THE
WEEKEND....FOLLOWING A BENIGN COLD FRONT FRIDAY NIGHT/SATURDAY
MORNING. MODELS ARE NOT IN AGREEMENT REGARDING THE ADVANCEMENT OF
THIS FRONT... AS THE ECMWF SENDS IT WELL SOUTH INTO THE TRANS PECOS
REGION WHILE THE GFS STALLS IT HALFWAY THROUGH THE LBB CWA. GIVEN
THE WEAKENING STATE OF THE PASSING WAVE AND LACK OF SIGNIFICANT COLD
ADVECTION... GFS SEEMS MORE REASONABLE HERE... ALTHOUGH CONVECTIVE
SIGNAL IN GFS FOR SUNDAY AFTERNOON SEEMS SUSPECT GIVEN THE ANEMIC
UPPER FLOW AND LACK OF FORCING. BOTH MODELS SEEM TO HINT AT A
SLOW-APPROACHING TROUGH/CLOSED LOW SOMETIME EARLY NEXT WEEK... BUT
AT THIS POINT SOLUTIONS ARE TOO FAR APART AND TOO FAR AWAY TO PUT
MUCH STOCK IN.

.PRELIMINARY POINT TEMPS/POPS...
FRIONA 30 45 25 59 36 / 10 10 10 0 10
TULIA 31 46 26 60 38 / 10 10 10 0 10
PLAINVIEW 32 48 27 60 38 / 10 10 10 0 10
LEVELLAND 35 50 28 60 38 / 10 10 10 0 10
LUBBOCK 35 50 30 60 39 / 10 10 10 0 10
DENVER CITY 39 54 26 61 33 / 10 10 10 0 10
BROWNFIELD 38 51 28 61 35 / 10 10 10 0 10
CHILDRESS 36 48 33 62 40 / 10 10 10 0 10
SPUR 39 49 32 61 44 / 10 10 10 0 10
ASPERMONT 43 50 33 62 43 / 10 10 10 0 10

.LUB WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 7 AM CDT TUESDAY FOR THE FOLLOWING ZONES:
TXZ021>044.

99/99/26

AREA FORECAST DISCUSSION

NWS GREEN BAY WI

623 PM CDT WED APR 24 2013

UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 245 PM CDT WED APR 24 2013

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A HIGH PRESSURE
RIDGE AXIS STRETCHING FROM THE SOUTHERN GREAT PLAINS ACROSS NE
WISCONSIN TO JAMES BAY EARLY THIS AFTERNOON. QUIET WEATHER EXISTS
ACROSS THE FORECAST AREA CURRENTLY...BUT MORE ACTIVE CONDITIONS EXIST
UPSTREAM OVER NE MINNESOTA. A WEAK SHORTWAVE IS PUSHING AN AREA OF
RAIN AND SNOW SOUTH OF DULUTH AND INTO NW WISCONSIN. BUT THE MAIN
SHORTWAVE TROUGH IS STILL OUT OVER NORTH DAKOTA WHERE SCATTERED RAIN
AND SNOW SHOWERS ARE FLYING. IN THE HEAVIER SNOW SHOWERS...VISIBILITIES
ARE FALLING TO AROUND A HALF TO THREE QUARTERS OF A MILE. AS THESE
SHORTWAVE TROUGHS PASS ACROSS THE FORECAST AREA TONIGHT...PRECIP
CHANCES AND AMOUNTS ARE THE MAIN FORECAST CONCERNS.

TONIGHT...THE MAIN SHORTWAVE TROUGH WILL SHARPEN AS IT DIGS ACROSS
THE NORTHERN MISSISSIPPI THIS EVENING AND THE STATE OF WISCONSIN
TONIGHT. A WEAK LITTLE WAVE OVER NORTHERN MINNESOTA WILL PUSH A
LEAD AREA OF PRECIP ENE ACROSS NORTH-CENTRAL WISCONSIN EARLY THIS
EVENING. DESPITE DEWPOINTS IN THE TEENS IN THIS REGION
CURRENTLY...PRECIP RATES LOOK IMPRESSIVE ENOUGH ON RADAR TO THINK
PRECIP WILL REACH THE GROUND EARLY THIS EVENING. THE PRECIP WILL BE
ARRIVING JUST AFTER PEAK HEATING...SO THINK PRECIP WILL START OUT AS
RAIN...THOUGH CANT RULE OUT SNOW FLAKES MIXING IN WITH THE RAIN
DROPS WITHIN THE HEAVIER SHOWERS. THE MAIN SHORTWAVE WILL THEN MOVE ACROSS
THE REGION LATE THIS EVENING THROUGH THE MIDDLE OF THE OVERNIGHT
PERIOD. SATELLITE AND RADAR UPSTREAM LOOK RATHER SHOWERY...PARTLY
CONTRIBUTED TO STEEP MID-LEVEL LAPSE RATES AROUND 8 C/KM. THINK
PRECIP WILL REMAIN SHOWERY TONIGHT DESPITE LOSS OF DIURNAL HEATING.
SURFACE WET BULB TEMPS STRUGGLE TO FALL BELOW FREEZING DURING THE
PERIOD THE PRECIP IS EXPECTED TO FALL...SO PTYPE WILL REMAIN
UNCERTAIN. THINK PRECIP WILL MAINLY BE RAIN OR A RAIN/SNOW MIX THIS
EVENING...CHANGING OVER TO SNOW AFTER MIDNIGHT AS SLIGHTLY COLDER
AIR MOVES IN BEHIND A SURFACE TROUGH. BUT THE ABOVE FREEZING WET
BULB TEMPS SUGGEST ACCUMS WILL BE LIMITED...PERHAPS A HALF INCH TO
AN INCH ON GRASSY SURFACES (HIGHER NORTH). PRECIP TO EXIT LATE
TONIGHT AND SKIES MAY PARTIALLY CLEAR OVER CENTRAL AND EAST-CENTRAL
WISCONSIN. LOWS IN THE UPPER 20S NORTH TO MID 30S SOUTH.

THURSDAY...SOME CLOUDS TO LINGER THURSDAY MORNING AND WILL GO
WITH A PARTLY TO MOSTLY CLOUDY START TO THE DAY AS RESIDUAL
MOISTURE AND CYCLONIC FLOW REACTS WITH DIURNAL HEATING.
HOWEVER...MIXING AND A WEAK 850MB RIDGE AXIS SHOULD LEAD TO
DECREASING CLOUDS IN THE AFTERNOON. HIGHS A DEGREE OR TWO COOLER
THAN TODAY.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 245 PM CDT WED APR 24 2013

MAIN FCST CONCERNS ARE PCPN TRENDS THU NGT INTO FRIDAY...AND
DURING THE EARLY TO MID PART OF THE NEXT WORK WEEK...AND FINALLY
SOME WARMER TEMPERATURES.

COOL NORTHWEST FLOW WILL BE REPLACED BY A ZONAL WESTERLY FLOW BY
THE WEEKEND...THEN BECOME MORE AMPLIFIED WITH SOUTHWEST FLOW AS A
TROF DEEPENS OVER THE ROCKIES AND NORTHERN PLAINS DURING THE EARLY
TO MID PART OF THE NEXT WORK WEEK. THE BIGGEST CHANGE WILL BE MUCH
WARMER AND ABOVE NORMAL TEMPS...WITH HIGHS WARMING INTO THE 60S
AND LOWER 70S FOR MOST OF THE PERIOD. THE WARMEST DAYS LOOK LIKE
THEY WILL OCCUR ON MONDAY AND TUESDAY.

FAIRLY STRONG WAA/ISENT LIFT WILL DEVELOP THURSDAY NIGHT...AND
CONTINUE INTO FRIDAY MORNING. IN ADDITION...A S/W TROF WILL TRACK
ACROSS THE REGION LATE THURSDAY NIGHT AND FRIDAY. RH/OMEGA
TIMESECTIONS INDICATE THAT MOISTURE WILL BE SOMEWHAT LACKING...
WITH PCPN NOT DEVELOPING UNTIL AFTER 09Z/FRI IN OUR WESTERN COUNTIES.
LOW-LEVEL THICKNESSES AND TEMPS INDICATE THAT PCPN SHOULD BE MAINLY
RAIN ACROSS CENTRAL WI...BUT A LIGHT MIX OF SNOW/SLEET/RAIN MAY
BRIEFLY OCCUR IN NC WI. DO NOT PLAN TO CARRY A MIX INTO FRIDAY...
AND WILL JUST HAVE A CHANCE OF SHOWERS ACROSS THE CWA.

GENERALLY DRY CONDITIONS ARE EXPECTED FROM FRIDAY NIGHT THROUGH
SUNDAY...MAKING FOR A VERY NICE AND MILD WEEKEND.

A WEAKENING COLD FRONT AND RRQ OF AN UPPER LEVEL JET WILL BRING A
CHANCE OF SHOWERS/ISOLD TSTMS TO OUR NW COUNTIES SUNDAY NIGHT. THE
FRONT IS EXPECTED TO BECOME ORIENTED MORE WEST TO EAST ACROSS THE
AREA ON MONDAY...THEN LIFT NORTH AS A WARM FRONT ON MONDAY NIGHT
AS LOW PRESSURE ORGANIZES IN THE NORTHERN PLAINS. THE THREAT OF
SHOWERS AND TSTMS WILL CONTINUE ALONG THIS BOUNDARY. A STRONGER...
BUT SLOW MOVING COLD FRONT WILL EDGE TOWARD THE AREA TUESDAY INTO
WEDNESDAY...WITH MAINLY POST-FRONTAL PCPN EXPECTED. PCPN ASSOCIATED
WITH THIS FEATURE SHOULD ARRIVE IN OUR NW COUNTIES TUES NGT...AND
ACROSS THE REST OF THE AREA ON WEDNESDAY.
&&

.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 623 PM CDT WED APR 24 2013

A VIGOROUS UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
TONIGHT AND PRODUCE WIDELY VARIABLE CEILINGS AND VISIBILITIES DUE
TO SNOW AND RAIN SHOWERS. THE SHOWERS WILL PRODUCE IFR CEILINGS
AND VISIBILITIES WHILE OUTSIDE OF THE SHOWERS IT WILL BE LARGELY VFR.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......RDM

AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

1056 AM CDT TUE APR 23 2013

.AVIATION/18Z TAFS/...SLUG OF RAIN SPREADING RAPIDLY ACROSS SE AND
PORTIONS OF SC WI. THIS ASSOCIATED WITH STRONG 200-300 MILLIBAR
JET STREAK SWINGING NE PER WATER VAPOR ANIMATION. ENHANCED UPPER
DIVERGENCE PROGGD BY GUID MAKES SENSE. COUPLE OF VORT MAXES ACROSS
SE IA AND NRN IL ENHANCING LIFT AS WELL. WINDS SETTING UP FROM THE
NORTHWEST IN THE WAKE OF THE FRONT. RAIN AREA WILL AFFECT SE CWA
INTO THE EVENING HOURS AND THEN TAPER OFF. CEILINGS PREDOMINANTLY
MVFR WITH VSBYS LOOKING TO BE IN THAT CATEGORY FOR THE MOST PART
WITH THE RAIN. WATCHING BACK EDGE CAREFULLY WITH COLDER AIRMASS
FILTERING IN. RAP SOUNDINGS TOO WARM IN THE LOW LEVELS...SO WET
FLAKES MIXING IN AT KMSN NOT OUT OF THE QUESTION. SHORTWAVE
RIDGING BUILDS IN LATER TONIGHT INTO WEDNESDAY AHEAD OF THE NEXT
WEATHER MAKER FOR WEDNESDAY NIGHT.

.PREV DISCUSSION... /ISSUED 356 AM CDT TUE APR 23 2013/

TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

FIRST BAND OF SCATTERED SHOWERS CROSSING CWA AHEAD OF SURFACE
COLD FRONT EARLY THIS MORNING IN REGION OF OF HIGHER LAYER
Q-VECTOR CONVERGENCE AND DIFFERENTIAL CVA WITH INITIAL SHORT
WAVE...AIDED BY WEAK UPPER LEVEL DIVERGENCE WITH COUPLED UPPER
JET...EXPECTED TO CLEAR THE FAR NE AROUND 12Z.

A SECOND AND MORE EXTENSIVE AREA OF PRECIPITATION IS EXPECTED TO
DEVELOP WITH FORCING AHEAD OF MAIN 500 MB TROUGH AND FRONTOGENETIC
RESPONSE LATER THIS MORNING AND THIS AFTERNOON. FOLLOWED TRENDS OF
HRRR AND RAP IN KEEPING MOST OF CWA DRY AFTER THE INITIAL EARLY
MORNING BAND...AND THEN BRINGING PRECIPITATION BACK INTO THE
FORECAST AREA FROM SW TO NE MID TO LATE MORNING WITH HIGHER POPS
WITH THE BETTER OMEGA IN THE SOUTHEAST 1/2 OF CWA. KEPT SLIGHT
CHANCE/CHANCE POPS OVER THE SE 1/2 UNTIL MID LEVEL TROUGH AXES
CLEAR THE REGION AROUND 06Z WED.

EARLY DAY HIGHS...WITH HIGHEST 12 MIDNIGHT TO 12 MIDNIGHT TEMPS
OCCURRING RIGHT NOW IN THE NW AHEAD OF COLD FRONT...THEN FALLING
WITH COLD FRONT PASSAGE...THOUGH THERE MAY BE A BRIEF RECOVERY OF
A FEW DEGREES IN THE NW MID-LATE AFTERNOON AS THE RAIN COMES TO AN
END.

COLD AIR ADVECTION/925 MB TEMPS -3C TO -4C BY 12Z WEDNESDAY/AND
CLEARING SKIES WILL DROP LOW TEMPERATURES INTO THE UPPER 20S
NW...WITH LINGERING CLOUDS KEEPING LOWS IN THE MID 30S SE.

WEDNESDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM
TO HIGH.

SHORT TERM MODELS SHOWING HIGH PRESSURE RIDGE SLIDING EAST THROUGH
THE REGION ON WEDNESDAY. THIS SHOULD BRING QUIET WEATHER TO THE
AREA. TEMPERATURES WILL BE ON THE COOL SIDE...GIVEN 925MB
TEMPERATURES ONLY AROUND 3 DEGREES CELSIUS.

MODELS ARE IN GOOD AGREEMENT WITH STRONG COLD FRONT PUSHING EAST
THROUGH THE AREA WEDNESDAY EVENING...WITH A STRONG 500MB SHORTWAVE
TROUGH MOVING THROUGH DURING THE EVENING INTO THE OVERNIGHT HOURS.
850MB LOW LEVEL JET NOSE POINTS INTO THE AREA DURING THE EVENING
AS WELL. AREA FORECAST SOUNDINGS SHOWING AIR COLUMN SATURATING FOR
A TIME GENERALLY BETWEEN 02Z AND 08Z THURSDAY...THEN DRYING OUT
WITH DRY AIRMASS MOVING IN BEHIND THE COLD FRONT AND SHORTWAVE
TROUGH.

WILL CONTINUE HIGHER END POPS WEDNESDAY EVENING INTO THE OVERNIGHT
HOURS...THEN TREND DOWN LATER IN THE NIGHT. PRECIPITATION WILL
START AS RAIN...THEN BECOME MIXY...THEN CHANGE TO SNOW FROM WEST
TO EAST IN THE LATE EVENING AND SOON AFTER MIDNIGHT. MAY SEE A
DUSTING OF SNOWFALL ON GRASSY AREAS...ESPECIALLY NORTHWEST OF
MADISON.

MODELS IN GOOD AGREEMENT WITH ANOTHER HIGH PRESSURE RIDGE SLIDING
ACROSS THE REGION THURSDAY...BEFORE GRADUAL WARM AIR ADVECTION
SHIFTS INTO THE REGION THURSDAY NIGHT. AREA FORECAST SOUNDINGS DRY
OUT DURING THIS TIME...SO SHOULD SEE QUIET WEATHER RETURN.
TEMPERATURES WILL REMAIN COOL ON THURSDAY...BEFORE BEGINNING TO
MODERATE THURSDAY NIGHT.

FRIDAY THROUGH MONDAY...FORECAST CONFIDENCE IS MEDIUM.

GFS/ECMWF ARE IN FAIR AGREEMENT WITH TRENDS FRIDAY INTO SATURDAY
NIGHT. THEY CONTINUE TO BRING A GRADUAL WARM AIR ADVECTION PATTERN
INTO THE REGION. AREA OF QPF WITH WARM FRONT REMAINS NORTH OF THE
AREA FRIDAY...WITH ANOTHER LARGER QPF AREA WITH 500MB SHORTWAVE
TROUGH REMAINING WELL TO THE SOUTH. THIS SHOULD RESULT IN A DRY
PERIOD...WITH SLOWLY MODERATING TEMPERATURES. DID LEAVE LOW POPS
IN FRIDAY NIGHT PER COORDINATION WITH SURROUNDING OFFICES...BUT
THIS PERIOD MAY END UP DRY AS WELL.

DIFFERENCES BETWEEN THE GFS/ECMWF SHOW UP SUNDAY INTO MONDAY. GFS
BRINGS A STRONG COLD FRONT EAST THROUGH THE REGION SUNDAY
NIGHT/MONDAY AND BEYOND...WITH THE ECMWF KEEPING IT WELL NORTHWEST
OF THE AREA. BOTH MODELS DO KEEP AREA IN MILD AIRMASS INTO
MONDAY...THOUGH ONSHORE WINDS SHOULD KEEP LAKESHORE AREAS COOLER.
WILL USE CONSENSUS POPS AND TEMPERATURES IN THIS PERIOD FOR NOW.

AVIATION/12Z TAFS/...

SCATTERED LIGHT RAIN SHOWERS WITH VFR CIGS WILL EXIT TAF SITES BY
12Z...FOLLOWED BY A MORE EXTENSIVE AREA OF RAIN WITH MVFR CIGS
MOVING IN BY MID-LATE MORNING. LIGHT TO AT TIMES MODERATE
RAIN...ESPECIALLY AT EASTERN TAF SITES...THROUGH THE AFTERNOON
WILL TAPER OFF FROM NW TO SE DURING THE EARLY EVENING...CLEARING
KENW BY 06Z WEDNESDAY. CURRENT POST-FRONTAL IFR DECK WILL REMAIN
WEST OF TAF SITES THROUGH MID-MORNING...BUT WILL BRING IN IFR WITH
THE THE STEADIER RAIN SHOWERS. VFR CONDITIONS RETURN WITH PASSAGE
OF MID-LEVEL TROUGH AFTER 06Z.

MARINE...

SOME NW GUSTS COULD REACH SMALL CRAFT CRITERIA LATE
AFTERNOON/EARLY EVENING BUT NOT WIDESPREAD OR FREQUENT ENOUGH FOR
A HEADLINE AT THIS TIME BUT WILL MONITOR CLOSELY. BETTER CHANCE
FOR SMALL CRAFT CONDITIONS COMES WEDNESDAY NIGHT INTO THURSDAY
WITH TIGHTENING PRESSURE GRADIENT BEHIND SURFACE LOW PRESSURE THAT
CROSSES LAKE SUPERIOR.

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...WOOD

AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

356 AM CDT TUE APR 23 2013

.TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

COLD AIR ADVECTION/925 MB TEMPS -3C TO -4C BY 12Z WEDNESDAY/AND
CLEARING SKIES WILL DROP LOW TEMPERATURES INTO THE UPPER 20S
NW...WITH LINGERING CLOUDS KEEPING LOWS IN THE MID 30S SE.

.WEDNESDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM
TO HIGH.

.FRIDAY THROUGH MONDAY...FORECAST CONFIDENCE IS MEDIUM.

.AVIATION/12Z TAFS/...

.MARINE...

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...WOOD

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

1138 PM CDT MON APR 22 2013

.UPDATE...
ISSUED AT 852 PM CDT MON APR 22 2013

A SURFACE LOW PRESSURE SYSTEM CURRENTLY ANALYZED IN NORTHEAST IOWA
JUST TO THE SOUTHWEST OF DECORAH IOWA WILL CONTINUE TO TRACK TO
THE EAST NORTHEAST ALONG A WARM FRONT THAT EXTENDS EAST OF THIS
LOW THROUGH CENTRAL WISCONSIN. THE MAIN FOCUS WITH THE NEAR TERM
FORECAST IS WITH WHEN/WHERE THE CHANGE OVER TO SNOW WILL TAKE
PLACE. THE WARM LAYER IS AT 850MB WITH THE 0C ISOTHERM RUNNING
ALONG THE FORECAST AREA BOUNDARY BETWEEN US AND MPX WHICH RUNS
ACROSS SOUTHEAST MINNESOTA NORTHEAST INTO NORTH CENTRAL WISCONSIN.
TO THE SOUTHEAST OF THE 0C 850MB ISOTHERM...PRECIPITATION IS
FALLING ALL AS RAIN WITH TEMPERATURES WELL ABOVE FREEZING. ALONG
THIS ISOTHERM...PRECIPITATION QUICKLY CHANGES FROM RAIN TO SLEET
TO SNOW. BRIGHT BANDING ON THE 0.5DEG KARX REFL/CC SHOWS THIS
MELTING LAYER AND IT LOOKS LIKE THE CHANGE OVER HAPPENS RIGHT
ALONG AND NORTHWEST OF THIS BAND. LOOKING FURTHER WEST...THE BACK
EDGE OF THE SNOW IN SOUTH CENTRAL MINNESOTA IS MAKING SOME QUICK
PROGRESS EASTWARD AS WELL AND IS TRENDING FASTER THAN WHAT THE
PREVIOUS MODELS HAD ADVERTISED. THE 22.23Z HRRR HAS LATCHED ONTO
THIS IDEA AS WELL AND HAVE USED AN EXTRAPOLATION/HRRR BLEND TO TRY
AND TIME DOWN THE PROGRESS EASTWARD OVERNIGHT. THE MAIN
COUNTY/AREA OF CONCERN FOR SNOW ACCUMULATION APPEARS TO BE IN
DODGE COUNTY MINNESOTA BETWEEN NOW AND 6Z TONIGHT. 22.23Z RAP
SOUNDINGS ALSO SHOW A QUICK LOSS OF ICE IN THE PROFILE AS THE BACK
EDGE MOVES THROUGH WHICH MEANS THAT DRIZZLE/FREEZING DRIZZLE WILL
BE POSSIBLE IF THERE IS ANY LOW LEVEL FORCING LEFT BEHIND THIS
SYSTEM.

THE QUESTION THEN BECOMES WITH SURFACE TEMPERATURES AND WHETHER IT
WILL COOL DOWN TO FREEZING OR NOT OVERNIGHT. TEMPERATURES ARE
MAINLY AT OR ABOVE FREEZING THROUGH MUCH OF THE REGION WITH NOT
MUCH IN THE WAY OF INITIAL COLD AIR ADVECTION COMING IN OVERNIGHT.
THE 32F SURFACE ISOTHERM IS JUST OFF TO THE NORTHWEST...SO WILL
HAVE TO WATCH THAT OVERNIGHT AND IF THE DRIZZLE DOES FORM AS WELL
WHICH COULD CREATE SOME SLICK CONDITIONS.

WILL NOT BE MAKING ANY CHANGES TO THE GOING HEADLINES RIGHT NOW.
AS MENTIONED...DODGE COUNTY WOULD BE THE MAIN CONCERN FOR HIGHEST
SNOWFALL TOTALS AT AN INCH...MAYBE TWO...BUT THE SNOW WILL LIKELY
ONLY OCCUR FOR A FEW HOURS THIS EVENING BEFORE THE FRONTOGENESIS
SHIFTS NORTHEAST. NOT VERY CONFIDENT THAT TAYLOR COUNTY WILL GET
MUCH SNOW...BUT PHILLIPS HAS BEEN REPORTING SNOW FOR THE PAST
COUPLE HOURS AND THEY COULD STILL SEE SOME SNOW IN THE NORTHWEST
PART OF THE COUNTY.

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 347 PM CDT MON APR 22 2013

POSITIVITY TILTED UPPER LEVEL TROUGH MOVING THROUGH WITH A FEW
EMBEDDED SHORTWAVES NOTED THAT WILL IMPACT THE REGION TONIGHT AND
TUESDAY...ONE ACROSS THE NORTHERN PLAINS...AND A SECOND ROTATING
THROUGH THE INTERMOUNTAIN WEST. AT THE SURFACE...MAIN AREA OF LOW
PRESSURE IS SITUATED IN SOUTHWESTERN KANSAS...WITH A SECONDARY LOW
DEVELOPING NEAR KANSAS CITY. A WARM FRONTAL BOUNDARY EXTENDS
NORTHEAST TO NEAR DES MONIES...LA CROSSE...AND WAUSAU. DEFORMATION
BANDING PRECIPITATION IS DEVELOPING ALONG AND NORTH OF THE
FRONT...LIFTING THROUGH THE AREA THIS AFTERNOON.

NEAR-TERM GUIDANCE AND MESO-MODEL SOLUTIONS IN GOOD AGREEMENT
SHOWING LOW PRESSURE RIDING ALONG THIS BOUNDARY TONIGHT...CENTERING
NEAR LA CROSSE BY 06Z. STRONG FRONTOGENETICAL FORCING ON THE
NORTHWEST SIDE WILL KEEP DEFORMATION BAND PRECIPITATION IN PLACE
ACROSS SOUTHERN MINNESOTA INTO PARTS OF WESTERN WISCONSIN.
BIGGEST FORECAST CONCERN REMAINS ON WHEN PRECIPITATION WILL
TRANSITION FROM RAIN TO A RAIN/SNOW MIX...THEN TO ALL SNOW...AND
WHAT SNOWFALL ACCUMULATIONS RESULT. 22.12Z PROBABILISTIC AND
DETERMINISTIC GUIDANCE DID NOT VARY TOO MUCH FROM PREVIOUS
RUNS...AND STILL POINT TO SOUTHERN INTO CENTRAL MINNESOTA...AND
THEN INTO NORTHWEST WISCONSIN WITH THE HIGHER THREAT OF
ACCUMULATING SNOW. LOCALLY...THE MOST CONCERN IS FOR EXTREME
NORTHWEST DODGE/WABASHA COUNTIES IN MINNESOTA...AND TAYLOR COUNTY
IN WISCONSIN WHERE 1 TO 2 INCHES ARE POSSIBLE. THIS CHANGE OVER IS
EXPECTED AROUND MIDNIGHT OR SO...SLOWLY WORKING EAST DURING THE
OVERNIGHT.

CROSS SECTIONS THROUGH SOUTHEAST MINNESOTA SHOW STRONG SLOPING
FRONTOGENETIC SIGNAL WITH NEGATIVE EPV ABOVE...SO CONVECTIVE ELEMENTS
ARE POSSIBLE. THIS WOULD ENHANCE PRECIPITATION RATES...AND ALLOW
DYNAMIC COOLING TO WIN OUT. END RESULT...THERE COULD BE QUICK
BURSTS OF SNOW IN THESE AREAS AND THIS WILL BE SOMETHING TO WATCH
CLOSELY TONIGHT. RIGHT NOW THE HIGHER THREAT IS JUST OFF TO THE
NORTHWEST.

SOUNDINGS SHOW THE ATMOSPHERE LOSES ICE SATURATION OVERNIGHT AS
SURFACE TEMPERATURES COOL TO NEAR FREEZING. COMBINED WITH A
RETREATING WARM NOSE AT 850 MB....THERE IS A BRIEF FREEZING RAIN
OR FREEZING DRIZZLE THREAT ACROSS PORTIONS OF SOUTHEAST MINNESOTA
INTO NORTH CENTRAL WISCONSIN. 22.09Z SREF PROBABILITIES DEPICT A
10 TO 30 PERCENT PROBABILITY AS WELL. HAVE INCREASED THIS SOME
FROM PREVIOUS FORECAST...AND A VERY MINOR GLAZE IS POSSIBLE.

FOR TUESDAY...THE SURFACE LOW IS EXPECTED TO LIFT INTO THE GREAT
LAKES AND THERE SHOULD BE A QUICK WEST TO EAST END TO PRECIPITATION
IN THE MORNING HOURS. PLAN ON BLUSTERY NORTHWEST WINDS 10 TO 20
MPH...WITH HIGHER GUSTS UP TO 30 MPH. SKIES WILL CLEAR DURING THE
AFTERNOON AS DRIER AIR WORKS IN ACROSS THE AREA ALONG WITH SURFACE
HIGH PRESSURE BUILDING IN. FINALLY...TEMPERATURES WILL BE NEARLY 20
DEGREES BELOW NORMAL..WITH LOWER 40S COMMON ACROSS THE AREA.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 347 PM CDT MON APR 22 2013

FOCUS IN THE LONG TERM IS ON A RATHER VIGOROUS NORTHERN STREAM
SHORTWAVE FOR WED/WED NIGHT...THEN LOOKING FORWARD TO THE
MUCH-ANTICIPATED FIRST SPRING WARM UP THAT IS POSSIBLE THIS WEEKEND.

FOR WEDNESDAY A POTENT SHORTWAVE TROUGH IS EXPECTED TO QUICKLY DIVE
OUT OF THE NORTHERN PLAINS IN THE AFTERNOON AND EVENING HOURS. THIS
SYSTEM IS CHARACTERIZED BY VERY STEEP LOW-LEVEL LAPSE RATES THANKS
TO AN ANOMALOUSLY COLD MID/UPPER LEVEL CORE. 500 MB STANDARDIZED
ANOMALIES OFF THE 22.00Z ECMWF VARY FROM 2 TO 2.5 SD BELOW NORMAL.
ALTHOUGH MOISTURE CONVERGENCE IS LACKING...THE MID/UPPER LEVEL
DYNAMICS LOOK TO BE SUFFICIENT ENOUGH TO WARRANT HIGHER
PRECIPITATION CHANCES. THERE REMAINS SOME TIMING DIFFERENCE BETWEEN
22.12 GUIDANCE...AND THE LATER ARRIVAL WOULD POINT TOWARD MORE A
RAIN/SNOW MIX. LOCATIONS NORTH OF I-94 COULD PICK UP A 1/2 INCH OF
SNOW LATE WEDNESDAY NIGHT AS COOLING CHANGES RAIN OVER TO WET SNOW.

THE LATE WEEK INTO THE UPCOMING WEEKEND FEATURES RETURN SOUTHWESTERLY
FLOW AS THE UPPER LEVEL FLOW RIDGING TAKES SHAPE. 850 MB
TEMPERATURES RISE FROM AROUND -5C ON THURSDAY...TO AS HIGH AS +10 TO
+14C BY SUNDAY. HIGHS FRIDAY/SATURDAY WILL RISE INTO THE 60S...WITH
LOW 70S POSSIBLE SUNDAY/MONDAY. DESPITE WARM TEMPERATURES...A
LINGERING BOUNDARY TO THE NORTH WARRANTS SLIGHT CHANCES NORTH OF
I-90 SATURDAY NIGHT INTO SUNDAY. THIS WILL BE WELCOME NEWS TO THOSE
WHO ARE LOOKING FORWARD TO SOME SPRING WEATHER...HOWEVER THIS COULD
POTENTIALLY CREATE HYDROLOGY ISSUES...SO SEE HYDROLOGY SECTION FOR
MORE DETAILS.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1138 PM CDT MON APR 22 2013

THE MAIN CHALLENGE WITH THE OVERNIGHT FORECAST IS WITH HOW FAST
FLIGHT CONDITIONS WILL IMPROVE THIS MORNING AND THROUGH THE
AFTERNOON HOURS AS A LOW PRESSURE SYSTEM TRACKS TO THE NORTHEAST
THROUGH THE GREAT LAKES. MVFR TO MAINLY IFR CONDITIONS ARE NOTED
ALONG THE BACK SIDE OF THIS LOW FROM WESTERN WISCONSIN ON THROUGH
SOUTHEAST MINNESOTA AND CENTRAL IOWA. THE MAIN PRECIPITATION BAND
IS CURRENTLY COMING TO AN END ACROSS SOUTHEAST MINNESOTA...THOUGH
SOME DRIZZLE OR LIGHT SNOW MAY CONTINUE AFTER THIS MAIN WAVE COMES
THROUGH. OVERALL...EXPECT THAT CONDITIONS WILL GRADUALLY IMPROVE
THROUGH THE MORNING AND AFTERNOON AS DRIER AIR MOVES IN. WINDS
WILL REMAIN GUSTY UNTIL TUESDAY EVENING WHEN A RIDGE OF HIGH
PRESSURE WILL PUSH IN FROM THE WEST.

.HYDROLOGY...TONIGHT/TUESDAY
ISSUED AT 347 PM CDT MON APR 22 2013

THE TONIGHT/TUESDAY EVENT IS EXPECTED TO RESULT IN 0.5 TO UP 1.0
INCH OF LIQUID ACROSS PORTIONS OF SOUTHEAST MINNESOTA AND WESTERN
INTO CENTRAL WISCONSIN. SATURATED GROUND FROM THE RECENT
RAINFALL...ALONG WITH SNOWPACK REMAINING IN PLACE ACROSS CENTRAL
MINNESOTA INTO NORTH CENTRAL WISCONSIN WILL KEEP AN ELEVATED RISK
OF HYDROLOGY ISSUES. FORECAST RAINFALL AMOUNTS BRING THE
TREMPEALEAU RIVER AT DODGE POTENTIALLY ABOVE FLOOD STAGE LATER
THIS WEEK BUT GIVEN SOME UNCERTAINTY IN WHAT BASINS WILL EXPERIENCE
THE HIGHER AMOUNTS...AT THIS TIME A FLOOD WATCH WAS POSTED.

LOOKING AHEAD...THE POSSIBLE SIGNIFICANT WARM UP ACROSS THE UPPER
MIDWEST THIS WEEKEND INTO EARLY NEXT WEEK COULD LEAD TO RAPID
SNOWMELT ACROSS CENTRAL MINNESOTA AND THE NORTHERN HALF OF
WISCONSIN. THIS WOULD LEAD TO SIGNIFICANT RISES ON AREA
TRIBUTARIES SUCH AS THE BLACK AND TREMPEALEAU RIVER...AND
EVENTUALLY ON THE MAIN STEM OF THE MISSISSIPPI RIVER. CURRENT
FORECASTS SHOW 1 TO 2 FEET RISES ON THE MISSISSIPPI BY THIS
WEEKEND...ABOVE ACTION STAGE AT MANY SITES.

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 9 AM CDT TUESDAY FOR WIZ017.

MN...NONE.
IA...NONE.
&&

UPDATE...HALBACH
SHORT TERM...ZT
LONG TERM...ZT
AVIATION...HALBACH
HYDROLOGY...ZT

AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

402 AM MDT THU APR 25 2013

.SHORT TERM...A WK CLOSED LOW OVR SRN CALIFORNIA WILL EJECT ENE
TOWARDS SRN CO BY TONIGHT. AHEAD OF THIS FEATURE THERE WILL BE AN
INCREASE IN MID AND HIGH LEVEL MOISTURE HOWEVER LOWER LEVELS ARE
RELATIVELY DRY. ENOUGH MOISTURE AND INSTABILITY MAY EXIST FOR A
FEW SHOWERS AND ISOLD TSTMS LATE THIS AFTN INTO THE EARLY EVENING
HOURS IN THE MTNS SOUTH OF I-70 AND ACROSS THE PALMER DIVIDE.
OTHERWISE ACROSS THE NRN HALF OF THE FORECAST AREA THRU TONIGHT.
AS FOR HIGH TEMPS LATEST RAP AND GFS SHOW HIGHS IN THE UPPER 60S
TO LOWER 70S ACROSS NERN CO WHILE THE NAM HAS HIGHS IN THE LOWER
TO MID 60S. AT THIS TIME WILL KEEP READINGS IN THE MID TO UPPER
60S ACROSS THE PLAINS.

.LONG TERM...MODELS SHOW A WEAK UPPER TROUGH AXIS TO MOVE EASTWARD
ACROSS THE FORECAST AREA ON FRIDAY. BY FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THE FLOW ALOFT IS WEAK AND NORTH-NORTHEASTERLY.
THE FLOW ALOFT STAYS WEAK SATURDAY AND SATURDAY NIGHT AND IS
MAINLY NORTHERLY. THERE IS WEAK DOWNWARD SYNOPTIC SCALE ENERGY FOR
THE CWA FRIDAY...THEN NEUTRAL ENERGY THROUGH SATURDAY NIGHT.
MODELS STILL HAVE WEAK UPSLOPE FLOW IN THE BOUNDARY LAYER ON
FRIDAY...THEN NORMAL DRAINAGE PATTERNS FRIDAY NIGHT. WEAK
DOWNSLOPING FLOW IS PROGGED ON SATURDAY. FOR MOISTURE...THERE IS
NOT A LOT COMPARED TO WHAT WE`VE SEEN FOR THE LAST MANY WEEKS.
THERE IS A BIT OF MID LEVEL MOISTURE PROGGED FRIDAY INTO
SATURDAY...BUT OVERALL IT IS PRETTY DRY. THERE IS A SMIDGEN OF
CAPE IN THE MOUNTAINS AND FOOTHILLS LATE DAY FRIDAY. THERE IS EVEN
LESS LATE DAY SATURDAY...AND IT IS STILL OVER THE HIGH COUNTY
ONLY. THE QPF FIELDS HAVE SLIGHT AMOUNTS OF MEASURABLE
PRECIPITATION OVER THE MOUNTAINS AND FOOTHILLS LATE DAY
FRIDAY...THEN NOTHING THROUGH SATURDAY NIGHT. WILL KEEP POPS OUT
FRIDAY THROUGH SATURDAY NIGHT. FOR TEMPERATURES...FRIDAY`S HIGHS
ARE SIMILAR TO TODAY`S. SATURDAY`S WARM-UP 3-5 C FROM FRIDAY`S.
FOR THE LATER DAYS...SUNDAY THROUGH WEDNESDAY...WEAK FLOW ALOFT IS
EXPECTED SUNDAY AND MONDAY. BY TUESDAY AND WEDNESDAY...A BROAD
UPPER TROUGH IS PROGGED TO MOVE ACROSS COLORADO. THE MAJORITY OF
ITS ENERGY STAYS TO OUR NORTH. THE ECMWF HAS BETTER UPSLOPE AND
MORE MOISTURE FOR A LONGER PERIOD OF TIME WITH THIS SYSTEM
COMPARED TO THE GFS. WILL KEEP POPS IN THE 20-30% RANGE FOR NOW.

.AVIATION...THERE WILL BE SOME INCREASE IN MID AND HIGH LEVEL
CLOUDS HOWEVER ANY PCPN LATE THIS AFTN AND EVENING SHOULD STAY
OVER THE PALMER DIVIDE AND NOT AFFECT THE AIRPORT. WINDS WILL
REMAIN SSW EARLY THIS MORNING...BY LATE MORNING THRU EARLY AFTN
THE RAP IS SHOWING A WK DENVER CYCLONE WITH LIGHT AND VARIABLE
WINDS MUCH OF THE AFTN. BY 00Z THE RAP SHOWS INCREASING SELY WINDS
POSSIBLY DUE TO HIGH BASED SHOWER ACTIVITY OVER THE PALMER DIVIDE
WHILE THE NAM HAS LIGHT N WINDS AT THE SAME TIME. FOR NOW WILL
KEEP WINDS LIGHT N AND THEN TRANSITON THEM TO MORE SSW BY 05Z.

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK

AREA FORECAST DISCUSSION

NWS DES MOINES IA

1202 AM CDT THU APR 25 2013

.SHORT TERM.../TONIGHT /...
ISSUED AT 419 PM CDT WED APR 24 2013

.LONG TERM.../THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 419 PM CDT WED APR 24 2013

.AVIATION...25/06Z
ISSUED AT 1159 PM CDT WED APR 24 2013

CDFNT HAS CLEARED ALL BUT THE KOTM AREA AND WILL BE PAST THEM BY
07Z. A FEW LINGERING SHOWERS...BUT THAT WILL END. SOME MVFR STRATOCU
WILL MOVE THROUGH HE KMCW AND KALO AREAS BEFORE 09Z. THE REST OF
THE TAF PERIOD AT ALL SITES WILL BE VFR. HIGH PRESSURE RIDGE WILL
ACROSS THE STATE THU. WNWLY WINDS WILL BECOME SW-SLY IN THE
AFTERNOON AND SLY AFTER SUNSET.

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

SHORT TERM...AWB
LONG TERM...KOTENBERG
AVIATION...MS APR 13

AREA FORECAST DISCUSSION

NWS GOODLAND KS

1129 PM MDT WED APR 24 2013

.UPDATE...
ISSUED AT 340 PM MDT WED APR 24 2013

.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 101 PM MDT WED APR 24 2013

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 115 PM MDT WED APR 24 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1125 PM MDT WED APR 24 2013

VFR CONDITIONS ARE FORECAST FOR THE 6Z TAFS. LITTLE CHANGE FROM
THE 0Z ISSUANCE. MAIN CONCERNS WILL BE WHEN WILL THE SOUTHWEST
WINDS INCREASE DURING THE MORNING...HOW FAST WILL THE GUSTS
BECOME...AND WHEN WILL THEY FALL OFF. DID BACK OFF THE WINDS FOR
KMCK SINCE THE SITE WILL BE FURTHER NORTH OF THE MAIN AREA OF
STRONGER GUSTS.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

UPDATE...JTL
SHORT TERM...DR
LONG TERM...99
AVIATION...JTL

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

330 AM EDT THU APR 25 2013

.SYNOPSIS...
ISSUED AT 330 AM EDT THU APR 25 2013

LOW PRESSURE WILL MOVE THROUGH LOWER MICHIGAN TODAY PRODUCING A
PERIOD OF MIXED RAIN AND SNOW. LITTLE IF ANY ACCUMULATION IS
EXPECTED AND SKIES WILL CLEAR LATE IN THE DAY. A CHILLY DAY IS
EXPECTED WITH HIGHS IN THE 40S. GENERALLY DRY WEATHER IS EXPECTED
THROUGH THE WEEKEND AND TEMPERATURES WILL CLIMB INTO THE 70S EARLY
NEXT WEEK.

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

FORECAST CONCERNS DEAL WITH PCPN CHANCES TODAY. WV LOOP SHOWS A
STRONG SHORT WAVE MOVING ACROSS WISCONSIN. RADAR ISN/T TOO
IMPRESSIVE WITH THIS WAVE. HOWEVER WITH MODEL TRENDS SHOWING AN
UPTICK IN STRENGTH AS IT APPROACHES WE MAY SEE THAT REFLECTED IN AN
EXPANDED AREAL COVERAGE OF PCPN. THERE HAS BEEN SOME SNOW OVER NRN
WISCONSIN WITH RAIN EXTENDING SOUTH INTO ILLINOIS. FCST SOUNDINGS
WOULD SUGGEST THE POSSIBILITY OF MIXED RAIN AND SNOW TODAY. IF A
HEAVIER CONVECTIVE CELL DEVELOPS IT/S POSSIBLE THAT THE GROUND COULD
BECOME BRIEFLY WHITE IN LOCALIZED AREAS. LATEST HRRR SHOWS PCPN
ENDING SHORTLY AFTER 18Z OVER THE ERN CWA. TEMPS TODAY WILL TOP OUT
IN THE 40S.

ANOTHER WEAKER SHORTWAVE WILL MOVE ACROSS NRN LWR FRIDAY. I/M NOT
CONVINCED IT/S STRONG ENOUGH TO PRODUCE PCPN OVER THE CWA SO WE
OPTED FOR DRY GRIDS FRIDAY. A STRONGER WAVE WILL PASS BY TO THE
SOUTH SATURDAY. ATTM IT APPEARS AS THOUGH PCPN WILL FALL SOUTH OF
THE CWA. UNDER QUASI ZONAL FLOW...TEMPS WILL GRADUALLY WARM INTO THE
60S BY SATURDAY.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

FINALLY A PERIOD OF ABOVE NORMAL TEMPERATURES CAN BE EXPECTED SUNDAY
THROUGH WEDNESDAY AS HEIGHTS RISE AHEAD OF A DIGGING/EVOLVING TROUGH
OVER THE NORTH CENTRAL UNITED STATES. HIGH TEMPERATURES OF 70 TO 75
ARE FORECAST.

WHILE MUCH OF THE LONG TERM PERIOD SHOULD BE DRY THERE ARE A FEW
THINGS TO WATCH. THE FIRST IS A SHORTWAVE WHICH IS PROGGED TO MOVE
THROUGH THE OHIO VALLEY REGION ON SUNDAY. MODELS HAVE BEEN TRYING TO
SQUEEZE OUT SOME LIGHT PRECIP ACROSS SRN LWR MI IN RESPONSE TO THIS
FEATURE BUT HAVE THE LEFT THE FCST DRY.

THE NEXT FEATURE WHICH COULD PRODUCE A FEW SHOWERS IS A FRONTAL
BOUNDARY APPROACHING FROM THE NORTHWEST ON MONDAY AND MONDAY NIGHT.
THIS WEAKENING/SLOWING FRONT MAY EVENTUALLY STALL OVERHEAD ON
TUESDAY BEFORE LIFTING BACK TO THE NORTH ON TUESDAY NIGHT/WEDNESDAY.

WILL HAVE SOME POPS MONDAY AND MONDAY NIGHT... MAINLY IN THE WRN AND
NRN CWFA... BUT LEFT TUESDAY DRY FOR NOW SINCE RIDGING ALOFT LOOKS
TO BECOME BETTER ESTABLISHED DURING THIS TIME. THIS RIDGING WILL
PROBABLY RESULT IN A SLOWER ARRIVAL OF THE UPSTREAM TROUGH DURING
THE MID WEEK PERIOD...BUT WILL CARRY LOW CHC POPS ON WEDNESDAY.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1156 PM EDT WED APR 24 2013

CONDITIONS START OUT VFR THEN SOME MVFR BY 12Z AS SOME RAIN MIXED
WITH WET SNOW ARRIVES. COULD BE PATCHY IFR WITH SNOW SHOWERS FROM
12Z TO 15Z THURSDAY...BUT THIS WAS LEFT OUT OF THE FORECAST FOR
NOW SINCE IT APPEARS TO BE VERY LOW CHANCE. WINDS WILL BE
SOUTHWEST IN THE MORNING GOING NORTHWEST BY LATE AFTERNOON.
WINDS WILL GUST OVER 20 KNOTS STARTING LATE TONIGHT AND THROUGH
THE AFTERNOON.

.MARINE...
ISSUED AT 330 AM EDT THU APR 25 2013

GUSTY WINDS EXPECTED WITH THE PASSAGE OF THE SHORT WAVE TODAY. THIS
WILL NECESSITATE THE ISSUANCE OF A SCA.

.HYDROLOGY...
ISSUED AT 330 AM EDT THU APR 25 2013

RIVERS WILL CONTINUE TO FALL THROUGH THE WEEKEND. TODAY/S PCPN WILL
BE UNDER A TENTH AND WILL HAVE LITTLE EFFECT ON RIVER LEVELS.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ844>849.

SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...OSTUNO
HYDROLOGY...93
MARINE...93

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1213 AM EDT THU APR 25 2013

.UPDATE...
ISSUED AT 1002 PM EDT WED APR 24 2013

REMOVED MENTION OF -FZRA FM FCST EARLIER TO REFLECT UNSTABLE LLVL
LAPSE RATES SHOWN ON FCST/OBSVD 00Z RAOBS AND ABSENCE OF ELEVATED
WARM LYR IN FCST SDNGS.
&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 527 PM EDT WED APR 24 2013

THU WILL SEE THE SYSTEM MOVING OUT IN THE MORNING...WITH DECREASING
CLOUDS THROUGHOUT THE DAY. EXPECT HIGHS IN THE 40S TO AROUND
50...COOLER NEAR LAKE SUPERIOR WITH ANY LAKE BREEZES THAT DEVELOP.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 527 PM EDT WED APR 24 2013

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1212 AM EDT THU APR 25 2013

EXPECT PREDOMINANT MVFR CONDITIONS ASSOCIATED WITH PASSING LO PRES
TROF CROSSING THE UPR LKS TO GIVE WAY TO VFR CONDITIONS THIS MRNG
AFTER SUNRISE WHEN DAYTIME HEATING WL TEND TO MIX OUT LINGERING LLVL
MSTR. ARRIVAL OF HI PRES RDG AXIS/DRIER AIR WL THEN BRING VFR
CONDITIONS THRU THE REST OF THE TAF PERIOD.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 527 PM EDT WED APR 24 2013

.HYDROLOGY...
ISSUED AT 527 PM EDT WED APR 24 2013

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...KC
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...KC
MARINE...VOSS
HYDROLOGY...VOSS

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

305 AM EDT THU APR 25 2013

.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING WITH THE
POSSIBILITY OF A FEW SHOWERS AND INCREASED CLOUD COVER. FRIDAY AND
SATURDAY LOOK GENERALLY NICE COURTESY OF HIGH PRESSURE TO THE
NORTHEAST. UNSETTLED CONDITIONS WILL RETURN SUNDAY AND CONTINUE
INTO THE NEW WORK WEEK.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM THURSDAY...GENTLE SOUTHWEST BREEZES EARLY THIS MORNING
WILL COME TO A CRASHING END IN JUST A FEW HOURS AS A COLD FRONT
PLOWS SOUTHEASTWARD OUT OF CENTRAL NORTH CAROLINA. LINEAR
EXTRAPOLATION OF THIS FRONT`S MOVEMENT AGREES RATHER WELL WITH THE
LATEST HRRR MODEL...WITH THE WIND SHIFT REACHING LUMBERTON AROUND
630 AM...FLORENCE AROUND 700 AM...WILMINGTON AROUND 800 AM...AND THE
MYRTLE BEACH AROUND BY 900 AM. THERE WILL BE A 2-3 HOUR PERIOD OF
GUSTY NORTH WINDS IMMEDIATELY BEHIND THE FRONT AS COLD ADVECTION
PROMOTES MIXING UP INTO STRONGER FLOW ALOFT...BUT THIS MOMENTUM WILL
DISSIPATE BY NOON WITH LIGHTER NORTHEAST WINDS EXPECTED THROUGH THE
DAY.

BESIDES PATCHES OF ALTOCUMULUS ACROSS SOUTH CAROLINA THERE AREN`T
THAT MANY CLOUDS OUT AHEAD OF THE FRONT CURRENTLY. MODEL FORECAST
SOUNDINGS SHOW A MOISTURE INCREASING THROUGH AND ABOVE THE FRONTAL
INVERSION BETWEEN 2500-7000 FEET LATER THIS MORNING...BUT WITHOUT AN
INCOMING UPPER DISTURBANCE OR ANY FAVORABLY POSITIONED JET STREAKS
TO PROMOTE SYNOPTIC LIFTING WE MAY SEE SKIES CLEAR OUT EARLIER THAN
THE SKY LINE IN THE GFS/NAM MOS BULLETINS SUGGEST. THIS WILL HAVE
IMPLICATIONS ON THE HIGH TEMPERATURE FORECAST AS WELL...AND I TEND
TO THINK THE GFS MOS HIGHS WILL VERIFY BETTER THAN THE COOLER NAM
MOS TODAY. GIVEN THAT THERE IS ALMOST UNANIMOUS SUPPORT IN THE 00Z
MODELS FOR SOME LIGHT POST-FRONTAL RAIN THIS MORNING I AM KEEPING A
20 POP IN THE FORECAST...ALTHOUGH IT`S TOUGH TO PIN DOWN EXACTLY
WHAT THE CAUSATIVE FACTOR WILL BE.

MOISTURE PUSHES OFFSHORE BY THIS EVENING WITH CLEAR SKIES
DEVELOPING. INITIALLY VERY LIGHT WINDS AT THE SURFACE AND 1000 FEET
UP WILL PROMOTE THE DEVELOPMENT OF A STRONG RADIATIONAL INVERSION
WITH TEMPERATURES FALLING INTO THE 40S BY 2 AM INLAND. AS HIGH
PRESSURE OVER THE OHIO VALLEY STRENGTHENS AND INCREASES OUR BOUNDARY
LAYER WINDS LATE...TEMPS WILL DRIFT ONLY ANOTHER FEW DEGREES DOWN BY
DAYBREAK WITH LOWS RANGING FROM THE LOW TO MID 40S INLAND...AND
UPPER 40S TO AROUND 50 ON THE BEACHES.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...THE MAIN FEATURE FOR THE SHORT TERM PERIOD IS THE
SHORTWAVE NOW CLEARLY SEEN IN SATELLITE IMAGERY ENTERING THE
SOUTHWEST. THIS SYSTEM WILL MOVE QUICKLY ACROSS THE CONUS AS IT
TRANSITIONS FROM A CLOSED LOW TO OPEN WAVE.

MODEL GUIDANCE HAS TRENDED SLOWER WITH THE SYSTEM AND IT NOW APPEARS
SATURDAY WILL BE A RELATIVELY NICE DAY WITH HIGH LEVEL MOISTURE
STREAMING ACROSS. I HAVE ALL BUT REMOVED THE MENTION OF POPS. I
WALKED BACK CHANCE VALUES FOR OVERNIGHT SATURDAY INTO SUNDAY MORNING
AS WELL AND WOULD NOT BE SURPRISED TO SEE POPS DELAYED FURTHER WITH
SUBSEQUENT MODEL GUIDANCE.

COOL HIGH PRESSURE FROM THE NORTHEAST WILL KEEP TEMPERATURES
SLIGHTLY BELOW CLIMATOLOGY ALTHOUGH STRONG LATE APRIL INSOLATION
SHOULD PROVIDE A BOOST FRIDAY MITIGATED SOMEWHAT BY THE CLOUD COVER
SATURDAY. I DID INCREASE HIGHS FOR SATURDAY ALTHOUGH THEY REMAIN
COOLER THAN FRIDAY.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...EXTENDED FORECAST REMAINS SOMEWHAT UNCERTAIN MAINLY
BEYOND SUNDAY WHEN CHANCE POPS REMAIN IN THE FORECAST VIA THE SYSTEM
NOW MOVING INTO THE SOUTHWEST. IT APPEARS A LOT OF THE MOISTURE
GENERATED BY FORECAST MODELS IS THE RESULT OF WEAK COLD AIR DAMMING
TO THE WEST. MORE SIGNIFICANT AND PROBABLY MORE REALISTIC QPF IS
ASSOCIATED WITH A LINGERING COASTAL TROUGH ACROSS MUCH OF OUR AREA.
I DID DECREASE POPS ALBEIT INCREMENTALLY MONDAY THROUGH WEDNESDAY
JUST TO REPRESENT THIS TREND. WE ARE GETTING INTO THE SEASON WHERE
MINIMAL FORCING CAN RESULT IN CONVECTION HOWEVER. NO CHANGES TO
TEMPERATURE FORECAST.

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...THE COLD FRONT IS SLOWING MAKING ITS WAY TOWARDS THE
EASTERN CAROLINAS...BUT CURRENT RADAR MOSAIC SHOWS NO PCPN
ASSOCIATED WITH THE FRONT. I EXPECT FROPA AROUND 11Z AT
KFLO/KLBT AND 12-13Z AT KILM/KMYR/KCRE. HOWEVER...HAVE JUST INCLUDED
VCSH FOR ALL TERMS AS RAIN CHANCES HAVE DIMINISHED. IT APPEARS THAT
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TODAY. TEMPO MVFR CIGS
ARE STILL POSSIBLE...BUT GUIDANCE HAS BACKED OFF OF THIS AS WELL.
WINDS WILL VEER TO THE N/NW FOLLOWING FROPA...BECOMING NE 10-15 KTS
AFTER DAYBREAK. SKIES WILL BEGIN CLEARING AFTER 00Z FRIDAY...AND THE
WINDS WILL BECOME AOB 5 KTS AFTER SUNSET.

EXTENDED OUTLOOK...CHANCE OF SHOWERS/MVFR LATE SATURDAY THRU MONDAY.
OTHERWISE VFR.

.MARINE...
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 3 AM THURSDAY...A COLD FRONT ZIPPING SOUTHEASTWARD ACROSS
CENTRAL NORTH CAROLINA WILL MAKE IT INTO THE COASTAL WATERS BETWEEN
8 AND 11 AM...WITH FAIRLY LIGHT SOUTHWEST WINDS SHIFTING TO THE
NORTH AND INCREASING TO 15 KNOTS WITH HIGHER GUSTS. THIS FRONTAL
SURGE WILL BE SHORT-LIVED...AND WITHIN JUST A COUPLE OF HOURS
NORTHEAST WINDS SHOULD DIE DOWN TO 10-12 KNOTS. ALTHOUGH RADARS
ACROSS THE CAROLINAS SHOW LITTLE IF ANY RAIN ACCOMPANYING THE FRONT
NOW MODELS SUGGEST AT LEAST A FEW PATCHES OF RAIN WILL DEVELOP
ACROSS THE COASTAL WATERS LATE THIS MORNING...DISSIPATING DURING THE
AFTERNOON HOURS.

FOR TONIGHT HIGH PRESSURE OVER THE OHIO VALLEY WILL GAIN STRENGTH
WITH ITS CENTRAL PRESSURE INCREASING 6 MILLIBARS OVER A 12 HOUR
PERIOD. THIS WILL BUILD THE PRESSURE GRADIENT OVER THE CAROLINAS
WITH THE COLD FRONT STALLING A FEW HUNDRED MILES OFFSHORE...AND
WINDS WILL AGAIN INCREASE TO 15 KNOTS WITH HIGHER GUSTS. THIS WILL
BE A LONGER DURATION OF WINDIER CONDITIONS COMPARED TO THIS
MORNING...AND SEAS WILL BUILD TO 4-5 FEET AWAY FROM SHORE LATE
TONIGHT.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE AT
THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A FEW
PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD AIR
ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE
NORTHEAST WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL
VEERING VIA THE SEABREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT
CRITERIA EARLY FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...WINDS AND SEAS WILL BE DICTATED BY THE POSITION
OF A COASTAL TROUGH/WARM FRONT LURKING JUST OFFSHORE. THE SEA
BREEZE...MORE LIKELY TO BE IN PLACE MONDAY WILL PLAY A ROLE AS WELL.
THE FORECAST HAS EASTERLY WINDS THROUGHOUT THE PERIOD BASICALLY ON
THE LOWER END OF A 10-15 KNOT RANGE. SEAS WILL HOVER IN A 2-4 FT
RANGE.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...BJR

AREA FORECAST DISCUSSION...UPDATED

NWS MILWAUKEE/SULLIVAN WI

347 AM CDT THU APR 25 2013

.VERY SHORT TERM...TODAY AND TONIGHT.

NARROW BAND OF RAIN SHOWERS WEAKENED WITH DIMINISHING LOW-LEVEL
FRONTOGENESIS AS IT CROSSED SOUTHERN WISCONSIN...THOUGH SOME
DOWNWARD MOMENTUM TRANSFER OF 30-40 KT WINDS AROUND 900 MB LED TO
WIND GUSTS UP TO 35 KNOTS AT LNR...30 KTS AT DLL...28 KTS AT MRJ AND
FLD...27 KTS AT EFT. GUSTS DIMINISHED IN INTENSITY WITH THE LOSS OF
MOMENTUM TRANSFER AS THE SHOWERS WEAKENED.

.TODAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

NARROW BAND OF LIGHT RAIN SHOWERS OVER SE WI ALONG SURFACE TROUGH
WILL EXIT BY 09Z...WITH DCVA-DRIVEN ISOLATED SHOWERS/SPRINKLES OVER
WESTERN CWA TO BE EAST OF CWA BY 12Z. HOWEVER...HI-RES/RAPID REFRESH
MODELS CONTINUE TO SHOW SPOTTY SHOWERS THIS MORNING IN REGION
BETWEEN DEPARTING WAVE TO THE NORTHEAST AND AHEAD OF SHORT WAVE
DROPPING THROUGH SW MN. WILL FOLLOW SHORT-TERM CONSENSUS AND KEEP A
SLIGHT CHANCE UNTIL MID MORNING. MODEL SOUNDINGS INDICATING
SCATTERED CUMULUS THIS AFTERNOON COULD BECOME BROKEN...WITH CAPE
APPROACHING 100 J/KG ON RAP SOUNDINGS...BUT MOISTURE MEAGER SO WILL
LEAVE DRY FOR NOW. 925 MB TEMPS RECOVER ENOUGH FOR HIGHS IN THE LOW
50S.

.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

INCREASING CLOUDS TONIGHT WITH WARM AIR ADVECTION ON STRONG
LOW-LEVEL JET WINDS AHEAD OF NEXT SHORT THAT WAVE BRINGS ISENTROPIC
ADIABATIC OMEGA INTO THE REGION AFTER MIDNIGHT. 00Z ECMWF FOCUSES
THE BETTER LIFT AND LOWER CONDENSATION PRESSURE DEFICITS NORTH OF
CWA...00Z NAM MAINLY ACROSS THE NORTHWESTERN CWA...WHILE 00Z GFS
BRINGS IT ACROSS THE ENTIRE CWA BETWEEN 06Z AND 12Z FRIDAY. CANADIAN
AS WELL AS ARW AND NMM WRF MODELS ALSO FOCUS PCPN CHANCES IN THE
NORTHERN/NORTHWEST CWA. WITH DRY AIR BELOW 800 MB TO BE OVERCOME
WILL LIMIT SLIGHT CHANCE POPS TO NW CWA CLOSER TO THE CONSENSUS
LOWER PRESSURE DEFICITS.

.FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO
HIGH.

SHORT TERM MODELS CONTINUE TO SHOW LIGHT QPF FRIDAY MORNING ACROSS
NORTHERN AND CENTRAL WISCONSIN WITH THE 850MB LOW LEVEL JET NOSE
AND FOCUSED WARM AIR ADVECTION/FRONTOGENESIS RESPONSE. THEY SHOW
LIGHT QPF LINGERING ACROSS THE FAR NORTHERN AND NORTHWESTERN
COUNTIES FRIDAY AFTERNOON AND NIGHT...AS SURFACE TROUGH SHIFTS
INTO THE AREA AND LOW LEVEL FRONTOGENESIS RESPONSE LINGERS.

AREA FORECAST SOUNDINGS IN THESE AREAS SUGGEST DECENT BUT NOT
DEEP MOISTURE IN AIR COLUMN...WITH A DRY LAYER IN THE LOW LEVELS.
WILL CONTINUE TO MENTION SLIGHT CHANCE TO CHANCE POPS FOR SHOWERS
FRIDAY IN THE FAR NORTHERN AND NORTHWESTERN COUNTIES...WITH LOW
POPS FOR SHOWERS LINGERING FRIDAY NIGHT.

OTHERWISE...HIGH PRESSURE SOUTHEAST OF THE AREA WILL BRING STEADY
WARM AIR ADVECTION THROUGH THE REGION FRIDAY INTO SATURDAY NIGHT.
THIS SHOULD LEAD TO STEADILY WARMING TEMPERATURES RISING ABOVE
NORMAL.

PERSISTENT SOUTHWEST WINDS WILL NEGATE A LAKE BREEZE
FRIDAY...WHICH WILL BRING WARM TEMPERATURES IN THE 60S TO THE
ENTIRE AREA. HIGHS SHOULD RISE INTO THE 60S AGAIN SATURDAY PER
925MB TEMPERATURES...WITH A LAKE BREEZE LATE IN THE AFTERNOON NEAR
THE SHORE.

.SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

GFS/ECMWF ARE IN FAIR AGREEMENT WITH FEATURES DURING THIS PERIOD.
THEY CONTINUE TO BRING THE WARMEST AIRMASS SO FAR THIS SPRING INTO
THE REGION SUNDAY INTO WEDNESDAY...WITH SOUTHERLY WINDS. 925MB
TEMPERATURES RISING INTO THE MID TEENS CELSIUS RANGE.
THIS...COMBINED WITH DECENT LOW LEVEL MIXING...SUGGEST HIGHS INTO
THE LOWER TO MID 70S SUNDAY THROUGH TUESDAY. LAKE BREEZE SHOULD
DEVELOP EACH AFTERNOON NEAR THE LAKE...COOLING TEMPERATURES DOWN
QUITE A BIT THERE.

GFS/ECMWF BRING COLD FRONT SOUTHEASTWARD INTO THE AREA MONDAY
AFTERNOON AND EVENING...BEFORE STALLING AND SHIFTING BACK
NORTHEASTWARD AS A WARM FRONT LATER MONDAY NIGHT INTO TUESDAY. QPF
WITH THE FRONT IS SEEN OVER MOST OF THE AREA. BROUGHT LOWER END
POPS INTO THE FORECAST FOR MONDAY INTO TUESDAY. ADDED SLIGHT
CHANCES FOR THUNDER WITH SOME CAPE IN GFS FORECAST SOUNDINGS.

GFS/ECMWF IN BETTER AGREEMENT WITH BRINGING STRONG COLD FRONT EAST
INTO THE AREA WEDNESDAY...WITH AN AMPLIFIED 500MB SHORTWAVE TROUGH
FOLLOWING CLOSE BEHIND. THIS WOULD BRING THE NEXT ORGANIZED CHANCE
FOR SHOWERS AND THUNDERSTORMS. MUCH COOLER TEMPERATURES WOULD THEN
MOVE INTO THE REGION FOR LATER IN THE WEEK.

.AVIATION/12Z TAFS/...WILL HAVE TO WATCH BAND OF MVFR CIGS...WITH
SOME LIGHT SPRINKLES/SHOWERS...RIGHT ALONG/BEHIND COLD FRONT TO SEE
IF IT WILL LINGER LONGER THAN MID-MORNING OVER THE REGION. COULD
STILL SEE A FEW GUSTS TO 20 KNOTS THROUGH 15Z. OTHERWISE EXPECT
SCT-BKN CU THIS AFTERNOON...WITH ENOUGH MIXING TO KEEP DECKS AT VFR
LEVELS. WARM ADVECTION CLOUDS RETURN TONIGHT...BUT ANY PCPN WILL
STAY NORTHWEST OF TAF SITES.

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD

AREA FORECAST DISCUSSION

NWS GREEN BAY WI

1219 AM CDT THU APR 25 2013

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 245 PM CDT WED APR 24 2013

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 245 PM CDT WED APR 24 2013

MAIN FCST CONCERNS ARE PCPN TRENDS THU NGT INTO FRIDAY...AND
DURING THE EARLY TO MID PART OF THE NEXT WORK WEEK...AND FINALLY
SOME WARMER TEMPERATURES.

GENERALLY DRY CONDITIONS ARE EXPECTED FROM FRIDAY NIGHT THROUGH
SUNDAY...MAKING FOR A VERY NICE AND MILD WEEKEND.

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1218 AM CDT THU APR 25 2013

A VIGOROUS UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA
OVERNIGHT AND PRODUCE WIDELY VARIABLE CEILINGS AND VISIBILITIES
DUE TO SNOW AND RAIN SHOWERS. THE LOWER CIGS WILL BE CONFINED TO
OR JUST AFTER THE FROPA WHERE THE RAIN CHANGES TO SNOW. AFTER THIS
SHORT WAVE TROUGH WITH COLD FRONT DEPARTS TO THE EAST THIS
MORNING...VFR CONDITIONS WILL RETURN TODAY.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......TDH

AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

852 AM MDT THU APR 25 2013

.UPDATE...TEMPERATURES WILL BE WARMER TODAY AND BE NEAR NORMAL FOR
THIS TIME OF YEAR. AN UPPER LEVEL TROUGH WILL MOVE FROM THE
DESERT SOUTHWEST AND CROSS THE SOUTHERN ROCKIES TONIGHT. MODELS
MAY BE A TINY BIT TOO FAR NORTH ON PLACEMENT OF THIS TROUGH WHEN
COMPARING IT WITH SATELLITE. CURRENT FORECAST CALLS FOR A SLIGHT
CHANCE OF THUNDERSTORMS THIS AFTERNOON AND EVENING SOUTH OF I-70.
THIS LOOKS GOOD AT THIS TIME. WILL ONLY MAKE A FEW MINOR CHANGES
TO LINE UP WITH CURRENT TRENDS.

.AVIATION...LIGHT WINDS THIS MORNING WILL TURN EASTERLY AFTER 18Z.
ONLY EXPECT MID AND HIGH CLOUDS ACROSS THE DENVER AREA THROUGH
TODAY AND TONIGHT. A FEW SHOWERS AND PERHAPS WEAK THUNDERSTORMS
MAY FORM OVER THE SOUTHERN HALF OF COLORADO. THESE ARE EXPECTED TO
STAY SOUTH OF THE DENVER AREA. A WEAK COLD FRONT WILL CAUSE WINDS
TO SHIFT TO THE NORTH AFTER 06Z TONIGHT. HOWEVER WINDS SPEEDS ARE
EXPECTED TO REMAIN LESS THEN 20 KNOTS THROUGH THE NEXT 24 HOURS.

.PREV DISCUSSION... /ISSUED 402 AM MDT THU APR 25 2013/

SHORT TERM...A WK CLOSED LOW OVR SRN CALIFORNIA WILL EJECT ENE
TOWARDS SRN CO BY TONIGHT. AHEAD OF THIS FEATURE THERE WILL BE AN
INCREASE IN MID AND HIGH LEVEL MOISTURE HOWEVER LOWER LEVELS ARE
RELATIVELY DRY. ENOUGH MOISTURE AND INSTABILITY MAY EXIST FOR A
FEW SHOWERS AND ISOLD TSTMS LATE THIS AFTN INTO THE EARLY EVENING
HOURS IN THE MTNS SOUTH OF I-70 AND ACROSS THE PALMER DIVIDE.
OTHERWISE ACROSS THE NRN HALF OF THE FORECAST AREA THRU TONIGHT.
AS FOR HIGH TEMPS LATEST RAP AND GFS SHOW HIGHS IN THE UPPER 60S
TO LOWER 70S ACROSS NERN CO WHILE THE NAM HAS HIGHS IN THE LOWER
TO MID 60S. AT THIS TIME WILL KEEP READINGS IN THE MID TO UPPER
60S ACROSS THE PLAINS.

LONG TERM...MODELS SHOW A WEAK UPPER TROUGH AXIS TO MOVE EASTWARD
ACROSS THE FORECAST AREA ON FRIDAY. BY FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THE FLOW ALOFT IS WEAK AND NORTH-NORTHEASTERLY.
THE FLOW ALOFT STAYS WEAK SATURDAY AND SATURDAY NIGHT AND IS
MAINLY NORTHERLY. THERE IS WEAK DOWNWARD SYNOPTIC SCALE ENERGY FOR
THE CWA FRIDAY...THEN NEUTRAL ENERGY THROUGH SATURDAY NIGHT.
MODELS STILL HAVE WEAK UPSLOPE FLOW IN THE BOUNDARY LAYER ON
FRIDAY...THEN NORMAL DRAINAGE PATTERNS FRIDAY NIGHT. WEAK
DOWNSLOPING FLOW IS PROGGED ON SATURDAY. FOR MOISTURE...THERE IS
NOT A LOT COMPARED TO WHAT WE`VE SEEN FOR THE LAST MANY WEEKS.
THERE IS A BIT OF MID LEVEL MOISTURE PROGGED FRIDAY INTO
SATURDAY...BUT OVERALL IT IS PRETTY DRY. THERE IS A SMIDGEN OF
CAPE IN THE MOUNTAINS AND FOOTHILLS LATE DAY FRIDAY. THERE IS EVEN
LESS LATE DAY SATURDAY...AND IT IS STILL OVER THE HIGH COUNTY
ONLY. THE QPF FIELDS HAVE SLIGHT AMOUNTS OF MEASURABLE
PRECIPITATION OVER THE MOUNTAINS AND FOOTHILLS LATE DAY
FRIDAY...THEN NOTHING THROUGH SATURDAY NIGHT. WILL KEEP POPS OUT
FRIDAY THROUGH SATURDAY NIGHT. FOR TEMPERATURES...FRIDAY`S HIGHS
ARE SIMILAR TO TODAY`S. SATURDAY`S WARM-UP 3-5 C FROM FRIDAY`S.
FOR THE LATER DAYS...SUNDAY THROUGH WEDNESDAY...WEAK FLOW ALOFT IS
EXPECTED SUNDAY AND MONDAY. BY TUESDAY AND WEDNESDAY...A BROAD
UPPER TROUGH IS PROGGED TO MOVE ACROSS COLORADO. THE MAJORITY OF
ITS ENERGY STAYS TO OUR NORTH. THE ECMWF HAS BETTER UPSLOPE AND
MORE MOISTURE FOR A LONGER PERIOD OF TIME WITH THIS SYSTEM
COMPARED TO THE GFS. WILL KEEP POPS IN THE 20-30% RANGE FOR NOW.

AVIATION...THERE WILL BE SOME INCREASE IN MID AND HIGH LEVEL
CLOUDS HOWEVER ANY PCPN LATE THIS AFTN AND EVENING SHOULD STAY
OVER THE PALMER DIVIDE AND NOT AFFECT THE AIRPORT. WINDS WILL
REMAIN SSW EARLY THIS MORNING...BY LATE MORNING THRU EARLY AFTN
THE RAP IS SHOWING A WK DENVER CYCLONE WITH LIGHT AND VARIABLE
WINDS MUCH OF THE AFTN. BY 00Z THE RAP SHOWS INCREASING SELY WINDS
POSSIBLY DUE TO HIGH BASED SHOWER ACTIVITY OVER THE PALMER DIVIDE
WHILE THE NAM HAS LIGHT N WINDS AT THE SAME TIME. FOR NOW WILL
KEEP WINDS LIGHT N AND THEN TRANSITION THEM TO MORE SSW BY 05Z.

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

UPDATE...MEIER
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...MEIER

AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

1030 AM EDT Thu Apr 25 2013

.NEAR TERM [Today and Tonight]...
Updated at: 1030 AM EDT

There has been decent coverage of light rain showers in the
Apalachicola River vicinity this morning, per TLH radar, and these
showers have continued to drift east to near a TLH-AAF line by 1430
UTC. For this reason, PoPs were increased into the higher "chance"
range for the aforementioned areas this morning and early this
afternoon. Not every location is likely to get measurable rain, but
most people from the Apalachicola River over to the Florida Big Bend
should see at least some sprinkles or drizzle. Because of the
continued cloud cover this morning, the temperatures were trended a
little bit cooler. If cloud cover lingers into the Noon hour, these
may need to be adjusted down a bit further. The best rain chances
will shift into the Florida Big Bend in the afternoon with the slow
moving cold front. RAP forecast MLCAPE is on the order of 500 j/kg,
so some thunder was also mentioned with the chances of rain showers.

Tonight, showers will drift south into the northern Gulf and
dissipate rather quickly. Expect temps to fall to near seasonal
averages across the southeast Big Bend tonight, and as low as 5 to
10 degrees below average across portions of Alabama and Georgia.
Generally, expect upper 40s to the NW, and upper 50s to the SE.

.SHORT TERM [Friday Through Saturday]...
After a seasonably cool start to Friday morning, a mostly sunny and
pleasantly warm day is in store for the region, with highs reaching
the lower to middle 80s. By Saturday, however, a fairly diffuse (to
begin with) low pressure system will be approaching the CWA from the
west, and it will bring gradually increasing chances for showers and
storms to the region as the day wears on. Highs should still reach
the lower 80s in most areas, but the latter half of the weekend
could be a bit more unsettled. Also, it should be noted that no
strong to severe storms are expected on Saturday

.LONG TERM [Saturday Night through Tuesday]...
This weekend, a low-amplitude mid-upper level trough is expected
to eject east from the southern Plains to the south Appalachians.
This trough is likely to evolve out of a closed low currently
(around 18 UTC Wednesday) situated off the southern California
coast. The increase in forcing for ascent should cause showers and
storms to gradually spread back into our area this weekend. After
that, the precise evolution of surface fronts is uncertain, but
some lingering boundaries and a continued moist and unstable
boundary layer should continue to support some isolated to
scattered convection into the early part of next week. With deep
westerly flow aloft across much of the southern latitudes of North
America, we should see a plume of steeper mid-level lapse rates
(associated with an elevated mixed layer from the Mexican plateaus
and desert Southwest) arrive by Sunday. The combination of steep
lapse rates, moderate instability, and deep layer shear around
30-40 knots suggests the potential for some stronger storms with
hail for Sunday, although things can certainly change by then.

.AVIATION ...

A mixture of fog, but primarily low ceilings has overspread our
terminals this morning. IFR restrictions will likely linger for a
couple of hours before giving way to MVFR ceilings, and later this
afternoon a return to VFR. Terminals to the north and west will be
quicker to clear. There is a very slight chance for showers at KTLH
both this morning and then again later this afternoon. The
probabilities are too low to mention in the TAF. Tonight, most
terminals will remain VFR under clear skies, however there is a
slight chance for MVFR ceilings late tonight at KVLD.

.MARINE...
Behind the passage of a diffuse Cold Front today, a favorable setup
for nocturnal surges out of the Northeast and East is expected to
impact the Coastal Waters tonight and Friday night. This is likely
to create a period of Cautionary conditions over the Marine area
into Saturday.

.FIRE WEATHER...
Red Flag conditions are not anticipated today. On Friday, long
durations of low relative humidity may pose problems across portions
of southeast Alabama and the Florida Panhandle. By the weekend,
southerly flow will transport enough moisture inland to quell any
Red Flag concerns.

.HYDROLOGY...
Although not too much rain is expected at this time, conditions will
gradually become more unsettled over the weekend into early next
week. Is is still much too early to speculate if there will be
enough rainfall to have an impact on area rivers.

Tallahassee 81 51 84 54 83 / 40 0 0 0 20
Panama City 77 58 80 61 78 / 20 0 0 0 30
Dothan 77 48 82 52 81 / 10 0 0 0 40
Albany 79 48 82 52 80 / 10 0 0 0 20
Valdosta 83 52 83 52 82 / 30 0 0 0 20
Cross City 84 57 85 54 84 / 20 10 10 0 20
Apalachicola 77 59 79 62 76 / 30 10 0 0 20

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.

NEAR TERM...Lamers/Harrigan
SHORT TERM...Gould
LONG TERM...Lamers
AVIATION...Harrigan
MARINE...Gould
FIRE WEATHER...Harrigan
HYDROLOGY...Gould

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

1158 AM EDT THU APR 25 2013

.SYNOPSIS...
ISSUED AT 330 AM EDT THU APR 25 2013

.UPDATE...
ISSUED AT 1159 AM EDT THU APR 25 2013

I ADDED ISOLATED THUNDERSTORMS TO OUR FORECAST FOR EASTERN CWA
THIS AFTERNOON. THAT WAS LARGELY BASED ON RAP AND NAM12 SOUNDING
WHICH SHOW ENOUGH INSTABILITY (200-400 J/KG) TO GET CLOUD TOPS TO
NEAR 20000 FT. THAT IS MORE THAN ENOUGH TO GET ECHO HEIGHTS ABOVE
THE -20C HEIGHT (12000 FT). DRY AIR AT MID LEVELS IS COMING IN
FROM THE WEST SO THERE IS ONLY A NARROW WINDOW OF TIME THEN THERE
IS ENOUGH MOISTURE AT MID LEVELS FOR THE CLOUDS TO DEVELOP
CONVECTION (MOSTLY PRIOR TO 21Z). ALSO THE SPC 09Z SREF SHOWS A 10
TO 20 PCT CHANCE OF THUNDERSTORMS WITHIN 3 HOURS OVER THE EASTERN
HALF OF LOWER MICHIGAN BETWEEN 2 PM AND 5 PM.

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

WILL HAVE SOME CHC POPS MONDAY AND MONDAY NIGHT... MAINLY IN THE
WRN AND NRN CWFA... BUT LEFT TUESDAY DRY FOR NOW SINCE RIDGING
ALOFT LOOKS TO BECOME BETTER ESTABLISHED DURING THIS TIME. THIS
RIDGING WILL PROBABLY RESULT IN A SLOWER ARRIVAL OF THE UPSTREAM
TROUGH DURING THE MID WEEK PERIOD...BUT WILL CARRY LOW CHC POPS ON
WEDNESDAY.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 747 AM EDT THU APR 25 2013

NUMEROUS MVFR CIGS/VSBYS CAN BE EXPECTED THIS MORNING AS RAIN
SHOWERS MOVE FROM WEST TO EAST. A PERIOD OF IFR CANNOT BE RULED
OUT AS WELL... ESPECIALLY AT GRR FROM 12Z TO 14Z AS A BAND OF
HEAVIER PRECIP POSSIBLY MIXED WITH SNOW MOVES THROUGH.

CONDITIONS SHOULD TREND TOWARD VFR THIS AFTERNOON BEHIND THE SFC
COLD FRONT BUT WEST WINDS WILL REMAIN RATHER STRONG WITH GUSTS TO
25 KTS. VFR IS LIKELY TONIGHT AS WINDS DIMINISH TO UNDER 10KTS.

.MARINE...
ISSUED AT 330 AM EDT THU APR 25 2013

GUSTY WINDS EXPECTED WITH THE PASSAGE OF THE SHORT WAVE TODAY. THIS
WILL NECESSITATE THE ISSUANCE OF A SCA.

.HYDROLOGY...
ISSUED AT 330 AM EDT THU APR 25 2013

RIVERS WILL CONTINUE TO FALL THROUGH THE WEEKEND. TODAY/S PCPN WILL
BE UNDER A TENTH AND WILL HAVE LITTLE EFFECT ON RIVER LEVELS.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ844>849.

UPDATE...WDM
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...MEADE
HYDROLOGY...93
MARINE...93

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

748 AM EDT THU APR 25 2013

.SYNOPSIS...
ISSUED AT 330 AM EDT THU APR 25 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 747 AM EDT THU APR 25 2013

CONDITIONS SHOULD TREND TOWARD VFR THIS AFTERNOON BEHIND THE SFC
COLD FRONT BUT WEST WINDS WILL REMAIN RATHER STRONG WITH GUSTS TO
25 KTS. VFR IS LIKELY TONIGHT AS WINDS DIMINISH TO UNDER 10KTS.

.MARINE...
ISSUED AT 330 AM EDT THU APR 25 2013

GUSTY WINDS EXPECTED WITH THE PASSAGE OF THE SHORT WAVE TODAY. THIS
WILL NECESSITATE THE ISSUANCE OF A SCA.

.HYDROLOGY...
ISSUED AT 330 AM EDT THU APR 25 2013

RIVERS WILL CONTINUE TO FALL THROUGH THE WEEKEND. TODAY/S PCPN WILL
BE UNDER A TENTH AND WILL HAVE LITTLE EFFECT ON RIVER LEVELS.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ844>849.

SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...MEADE
HYDROLOGY...93
MARINE...93

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

650 AM EDT THU APR 25 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM THURSDAY...JUST IN THE PAST 30 MINUTES A FEW SHOWERS
HAVE DEVELOPED ON RADAR COMPOSITES JUST NORTH AND WEST OF COLUMBIA
SC. THIS APPEARS TO LINE UP WITH AN AREA OF VERY WEAK ISENTROPIC
LIFT ON AND NEAR THE 300K THETA SURFACE DEPICTED BY THE 06Z
MODELS...APPROXIMATELY 7000 FT AGL. MODELS SHOW HIGH RELATIVE
HUMIDITY AT THIS LEVEL ADVECTING EAST TO THE COAST DURING THE
MORNING HOURS...BUT SHOW ONLY SPOTTY AND INCONSISTENT ISENTROPIC
LIFT ACCOMPANYING IT. DESPITE WEAK FORCING THE BULK OF THE LATEST
MODEL GUIDANCE SHOWS AN EXPANSION OF QPF THROUGH 15 AND 18Z. NO
SIGNIFICANT CHANGES HAVE BEEN MADE TO THE FORECAST THIS MORNING.
PREVIOUS DISCUSSION FROM 300 AM FOLLOWS...

GENTLE SOUTHWEST BREEZES EARLY THIS MORNING WILL COME TO A CRASHING
END IN JUST A FEW HOURS AS A COLD FRONT PLOWS SOUTHEASTWARD OUT OF
CENTRAL NORTH CAROLINA. LINEAR EXTRAPOLATION OF THIS FRONT`S
MOVEMENT AGREES RATHER WELL WITH THE LATEST HRRR MODEL...WITH THE
WIND SHIFT REACHING LUMBERTON AROUND 630 AM...FLORENCE AROUND 700
AM...WILMINGTON AROUND 800 AM...AND THE MYRTLE BEACH AROUND BY 900
AM. THERE WILL BE A 2-3 HOUR PERIOD OF GUSTY NORTH WINDS IMMEDIATELY
BEHIND THE FRONT AS COLD ADVECTION PROMOTES MIXING UP INTO STRONGER
FLOW ALOFT...BUT THIS MOMENTUM WILL DISSIPATE BY NOON WITH LIGHTER
NORTHEAST WINDS EXPECTED THROUGH THE DAY.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...THE MAIN FEATURE FOR THE SHORT TERM PERIOD IS
THE SHORTWAVE NOW CLEARLY SEEN IN SATELLITE IMAGERY ENTERING THE
SOUTHWEST. THIS SYSTEM WILL MOVE QUICKLY ACROSS THE CONUS AS IT
TRANSITIONS FROM A CLOSED LOW TO OPEN WAVE.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...EXTENDED FORECAST REMAINS SOMEWHAT UNCERTAIN
MAINLY BEYOND SUNDAY WHEN CHANCE POPS REMAIN IN THE FORECAST VIA THE
SYSTEM NOW MOVING INTO THE SOUTHWEST. IT APPEARS A LOT OF THE
MOISTURE GENERATED BY FORECAST MODELS IS THE RESULT OF WEAK COLD AIR
DAMMING TO THE WEST. MORE SIGNIFICANT AND PROBABLY MORE REALISTIC
QPF IS ASSOCIATED WITH A LINGERING COASTAL TROUGH ACROSS MUCH OF OUR
AREA. I DID DECREASE POPS ALBEIT INCREMENTALLY MONDAY THROUGH
WEDNESDAY JUST TO REPRESENT THIS TREND. WE ARE GETTING INTO THE
SEASON WHERE MINIMAL FORCING CAN RESULT IN CONVECTION HOWEVER. NO
CHANGES TO TEMPERATURE FORECAST.

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 12Z...A COUPLE OF OUR NORTHWEST SURFACE OBSERVATIONS ARE
SHOWING A WIND SHIFT TO THE NORTH AS A COLD FRONT SLOWLY DROPS IN
THIS MORNING. HAVE BACKED OFF A BIT OF THE GUSTY NATURE OF THE
SHIFT...BUT WE STILL SHOULD SEE WINDS ABOVE 15 KTS AT TIMES. A MVFR
CEILING IS POSSIBLE...BUT LEFT IT SCATTERED AT THIS TIME. ISOLATED
TO SCATTERED PRECIP IS EXPECTED TO DEVELOP ALONG THE FRONT LATER
THIS MORNING. THINK COVERAGE AT THIS TIME WILL BE LIMITED...WITH A
VCSH MENTION ONLY. ATMOSPHERE IS FAIRLY SATURATED TO 700 MB HOWEVER.
TONIGHT...ATMOSPHERE DRIES OUT WITH A CONTINUED NORTHERLY WIND...A
BIT MORE NORTHEASTERLY.

EXTENDED OUTLOOK...CHANCE OF SHOWERS/MVFR LATE SATURDAY THRU MONDAY.
OTHERWISE VFR.

.MARINE...
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 630 AM THURSDAY...NO SIGNIFICANT CHANGES ARE NEEDED TO THE
FORECAST. THE COLD FRONT IS RUNNING 30-45 MINUTES BEHIND SCHEDULE
ACROSS CENTRAL AND EASTERN NORTH CAROLINA WHICH SIMPLY DELAYS THE
VEERING TO NORTH WINDS A LITTLE LATER IN THE MORNING. PREVIOUS
DISCUSSION FROM 300 AM FOLLOWS...

A COLD FRONT ZIPPING SOUTHEASTWARD ACROSS CENTRAL NORTH CAROLINA
WILL MAKE IT INTO THE COASTAL WATERS BETWEEN 8 AND 11 AM...WITH
FAIRLY LIGHT SOUTHWEST WINDS SHIFTING TO THE NORTH AND INCREASING TO
15 KNOTS WITH HIGHER GUSTS. THIS FRONTAL SURGE WILL BE
SHORT-LIVED...AND WITHIN JUST A COUPLE OF HOURS NORTHEAST WINDS
SHOULD DIE DOWN TO 10-12 KNOTS. ALTHOUGH RADARS ACROSS THE CAROLINAS
SHOW LITTLE IF ANY RAIN ACCOMPANYING THE FRONT NOW MODELS SUGGEST AT
LEAST A FEW PATCHES OF RAIN WILL DEVELOP ACROSS THE COASTAL WATERS
LATE THIS MORNING...DISSIPATING DURING THE AFTERNOON HOURS.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE
AT THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A
FEW PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD AIR
ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE NORTHEAST
WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL VEERING VIA THE
SEABREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT CRITERIA EARLY
FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...WINDS AND SEAS WILL BE DICTATED BY THE
POSITION OF A COASTAL TROUGH/WARM FRONT LURKING JUST OFFSHORE. THE
SEA BREEZE...MORE LIKELY TO BE IN PLACE MONDAY WILL PLAY A ROLE AS
WELL. THE FORECAST HAS EASTERLY WINDS THROUGHOUT THE PERIOD
BASICALLY ON THE LOWER END OF A 10-15 KNOT RANGE. SEAS WILL HOVER IN
A 2-4 FT RANGE.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...43

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

642 AM EDT THU APR 25 2013

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...THE MAIN FEATURE FOR THE SHORT TERM PERIOD IS
THE SHORTWAVE NOW CLEARLY SEEN IN SATELLITE IMAGERY ENTERING THE
SOUTHWEST. THIS SYSTEM WILL MOVE QUICKLY ACROSS THE CONUS AS IT
TRANSITIONS FROM A CLOSED LOW TO OPEN WAVE.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...EXTENDED FORECAST REMAINS SOMEWHAT UNCERTAIN
MAINLY BEYOND SUNDAY WHEN CHANCE POPS REMAIN IN THE FORECAST VIA THE
SYSTEM NOW MOVING INTO THE SOUTHWEST. IT APPEARS A LOT OF THE
MOISTURE GENERATED BY FORECAST MODELS IS THE RESULT OF WEAK COLD AIR
DAMMING TO THE WEST. MORE SIGNIFICANT AND PROBABLY MORE REALISTIC
QPF IS ASSOCIATED WITH A LINGERING COASTAL TROUGH ACROSS MUCH OF OUR
AREA. I DID DECREASE POPS ALBEIT INCREMENTALLY MONDAY THROUGH
WEDNESDAY JUST TO REPRESENT THIS TREND. WE ARE GETTING INTO THE
SEASON WHERE MINIMAL FORCING CAN RESULT IN CONVECTION HOWEVER. NO
CHANGES TO TEMPERATURE FORECAST.

EXTENDED OUTLOOK...CHANCE OF SHOWERS/MVFR LATE SATURDAY THRU MONDAY.
OTHERWISE VFR.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE
AT THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A
FEW PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD AIR
ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE NORTHEAST
WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL VEERING VIA THE
SEABREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT CRITERIA EARLY
FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...WINDS AND SEAS WILL BE DICTATED BY THE
POSITION OF A COASTAL TROUGH/WARM FRONT LURKING JUST OFFSHORE. THE
SEA BREEZE...MORE LIKELY TO BE IN PLACE MONDAY WILL PLAY A ROLE AS
WELL. THE FORECAST HAS EASTERLY WINDS THROUGHOUT THE PERIOD
BASICALLY ON THE LOWER END OF A 10-15 KNOT RANGE. SEAS WILL HOVER IN
A 2-4 FT RANGE.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...BJR

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

1055 AM EDT THU APR 25 2013

.SYNOPSIS...
A WEAK DISTURBANCE CONTAINING LIMITED MOISTURE WILL CROSS THE
GREAT LAKES TODAY. HIGH PRESSURE AND DRY AIR WILL BUILD IN FOR
TONIGHT AND FRIDAY. LOW PRESSURE TRAVELING NEAR THE OHIO RIVER
WILL BRING A CHANCE OF SHOWERS ON SATURDAY AND SUNDAY.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK CDFNT AND H5 S/W ARE WORKING ACROSS THE REGION ATTM. LATEST
HRRR AND RAP RUNS ARE INDICATING THAT THE CHC OF SHOWERS MIGHT
DEVELOP MORE DURING THE AFTN IN THE BETTER INSTABILITY AND MIGHT
DEVELOP A LITTLE FARTHER S DOWN THE SCIOTO VALLEY. SO ADJUSTED THE
CHC OF SHRA LATE THIS MORNING TO ONLY THE EXTREME NW
COUNTIES...THEN AS THE AFTN HEATING KICKS IN DEVELOPED SHRA IN THE E
AND TOOK TO THE CHC DOWN TO ROSS COUNTY. KEPT THE POPS ONLY 20-30
HOWEVER.

MADE LITTLE ADJUSTMENT TO THE AFTN HIGHS. KEPT THE HIGHS IN THE UPPER
30S IN THE NW...RANGING TO THE UPPER 50S IN NRN KY.

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE CENTER OF HIGH PRESSURE WILL CROSS OHIO TONIGHT THEN INTO
PENNSYLVANIA ON FRIDAY. THIS WILL BRING A PERIOD OF DRY WEATHER
AND CLEAR SKIES. FROST WILL FORM AGAIN LATE TONIGHT THROUGH EARLY
FRIDAY MORNING WHEN TEMPERATURES WILL FALL INTO THE 30S. FROST
WILL MELT QUICKLY AFTER SUNRISE AND TEMPERATURES WILL RISE TO THE
LOWER 60S DURING FRIDAY AFTERNOON.

WEAK LOW PRESSURE WILL BE MOVING INTO THE LOWER OHIO RIVER
VALLEY ON SATURDAY. AIDED BY A COLD POOL ASSOCIATED WITH A 500 MB
TROUGH...THIS SYSTEM WILL CONTAIN ENOUGH FORCING AND MOISTURE TO
ALLOW A CHANCE OF SHOWERS ON SATURDAY...MAINLY FOR SOUTHERN
LOCATIONS. AFTER A MILDER FRIDAY NIGHT WITH LOWS IN THE
40S...TEMPERATURES ENHANCED BY WARM ADVECTION WILL TOP OUT IN THE
MID AND UPPER 60S ON SATURDAY.

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL BE DEPARTING THE CWA AT THE START OF THE
EXTENDED FORECAST PERIOD. MODEL AGREEMENT IS RELATIVELY POOR IN
HANDLING THE EVOLUTION OF A SLOW-MOVING MID-LEVEL TROUGH OVER THE
WEEKEND. EVEN AT 72HR ON THE 12Z GFSE...THERE IS SIGNIFICANT SPREAD
BETWEEN THE ENSEMBLE MEMBERS ON THE STRENGTH AND PLACEMENT OF THE
TROUGH. THE OPERATIONAL GFS SEEMS TO BE STRONGER WITH THE TROUGH
THAN MOST OF ITS MEMBERS...WHILE THE OPERATIONAL 12Z ECMWF IS A BIT
CLOSER TO THE GFSE MEAN.

.AVIATION /15Z THURSDAY THROUGH MONDAY/...
SFC HIGH PRESSURE TO SLIDE EAST ACRS THE REGION THIS MORNING. THIS
HI HAS PROVIDED LIGHT WINDS...MAINLY CLEAR SKIES AND GOOD SETUP FOR
RADIATIONAL COOLING. WITH RECENT RAINFALL AND MOIST GROUND...
FOG HAS DEVELOPED THIS MORNING. HAVE MVFR VSBY RESTRICTIONS AT
KCVG...KCMH AND KLCK WITH IFR RESTRICTION AT FOG PRONE KLUK.

MID LEVEL S/W TO PIVOT THRU THE GREAT LAKES TODAY. ASSOCIATED SFC
LOW TO TRACK THRU THE GREAT LAKES WITH SFC COLD FRONT DROPPING SE
THRU THE TAF SITES THIS AFTN. HAVE BKN-OVC CLOUDS DEVELOPING
BETWEEN 4000 AND 5000. WITH THE BEST MSTR ACRS THE NORTH A PASSING
SPRINKLE OR SHOWER WILL BE PSBL MAINLY ACRS KDAY/KCMH/KLCK TAF
SITES BUT CONDITIONS SHUD REMAIN VFR. HAVE HANDLED THIS WITH A MENTION
OF VCSH AT THESE TAF SITES DUE TO THE LIMITED COVERAGE.

SW WINDS AT 12 TO 15 KTS WILL BE COMMON WITH AFTERNOON GUSTS UP
TO 22 KTS PSBL. HIGH PRESSURE WILL RE-ESTABLISH ITSELF OVER THE
REGION TONIGHT WITH WINDS BECOMING LIGHT AND SKIES CLEARING OUT.

OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...SITES
SHORT TERM...CONIGLIO
LONG TERM...HATZOS
AVIATION...AR

AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

1047 AM CDT THU APR 25 2013

.AVIATION/18Z TAFS/...PRIMARY SHORTWAVE TROUGH LIFTING NORTHEAST
FROM MICHIGAN PER WATER VAPOR LOOP. SECONDARY WAVE SEEN CRUISING
ESE THROUGH IA. NIL IMPACT FROM THE LATTER. MORNING 12Z UPPER AIR
ANALYSIS SHOWED A -36C AT 500 MILLIBARS AT KGRB...-28C AT KMPX. SO
VERY COLD AIR UPSTAIRS AND THE STILL AN ELONGATED CYCLONIC FLOW IN
THE WAKE OF THE PRIMARY TROUGH AXIS. EXPECT BROKEN CUMULUS TO
LINGER THIS AFTERNOON WITH BASES GRADUALLY RISING ABOVE MVFR
LEVELS. INCREASING WAA TONIGHT WITH RH PANELS SUGGESTING MID
CLOUDS FROM 6-14Z. QPF FROM THIS WAA PROGGD TO STAY NORTH OF TAF
SITES..SO WILL RETAIN DRY TAFS.

.PREV DISCUSSION... /ISSUED 347 AM CDT THU APR 25 2013/

VERY SHORT TERM...TODAY AND TONIGHT.

TODAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO
HIGH.

SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

AVIATION/12Z TAFS/...WILL HAVE TO WATCH BAND OF MVFR CIGS...WITH
SOME LIGHT SPRINKLES/SHOWERS...RIGHT ALONG/BEHIND COLD FRONT TO SEE
IF IT WILL LINGER LONGER THAN MID-MORNING OVER THE REGION. COULD
STILL SEE A FEW GUSTS TO 20 KNOTS THROUGH 15Z. OTHERWISE EXPECT
SCT-BKN CU THIS AFTERNOON...WITH ENOUGH MIXING TO KEEP DECKS AT VFR
LEVELS. WARM ADVECTION CLOUDS RETURN TONIGHT...BUT ANY PCPN WILL
STAY NORTHWEST OF TAF SITES.

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD

AREA FORECAST DISCUSSION

NWS NEW YORK NY

130 PM EDT THU APR 25 2013

.SYNOPSIS...
HIGH PRESSURE THEN BUILDS INTO THE REGION THROUGH THE WEEKEND AND
WILL PERSIST INTO THE MIDDLE OF NEXT WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ADJUSTED HIGH TEMPERATURES DOWN FROM PREVIOUS FORECAST DUE TO
COLD ADVECTION CONTINUING THROUGH THE DAY AND RELATIVELY WEAK
WINDS IN THE LOWER LEVELS. USED THE LATEST 12Z NAM AND
INCORPORATED MIXING TO H85. ALONG THE COAST WHERE AFTERNOON SEA
BREEZE DEVELOPMENT IS ANTICIPATED...BLENDED IN THE LATEST RAP MODEL
MAX TEMPERATURES. THIS GIVES HIGHS IN THE UPPER 50S INLAND TO
LOWER 60S IN NYC AND LONG ISLAND. TEMPERATURES SHOULD BEGIN TO LEVEL
OFF ONCE THE SEA BREEZE PASSES AND BEGIN TO COOL WITH WINDS
TURNING TO THE SOUTH.

WINDS ARE STILL EXPECTED TO DIMINISH BY THE AFTERNOON TO 10 TO 15
MPH WITH A SUNNY SKY CONDITION.

OTHERWISE...FORECAST REMAINS ON TRACK.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
UPPER LEVEL TROUGH PASSES TO THE N TONIGHT. DO NOT EXPECT ANY
PCPN THIS FAR S...JUST A TEMPORARY INCREASE IN CLOUD COVER...
THEREFORE REMOVED SCHC POPS. LIGHT WINDS AND MOSTLY CLEAR SKIES
TONIGHT WILL ALLOW FOR GOOD RADIATIONAL COOLING CONDITIONS. IT
WILL BE CHILLY ONE ACROSS THE INTERIOR AND PINE BARRENS OF LONG
ISLAND...DROPPING INTO THE LOWER 30S. ELSEWHERE...OVERNIGHT LOWS
WILL BE SLIGHTLY BELOW NORMAL LEVELS IN THE UPPER 30S TO LOWER
40S...MID 40S IN METRO NYC/NJ.

FAIR AND DRY CONDS THEN PREVAIL THROUGH FRI AS HIGH PRES BUILDS
TOWARDS THE AREA. A LIGHT W-NW WIND IS EXPECTED TO ONCE AGAIN GIVE
WAY TO A SEABREEZE AT THE COAST DURING THE AFTN. HIGHS WILL BE A
FEW DEGREES WARMER THAN TODAY...GENERALLY MID TO UPPER 60S.

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
H5 TROUGH/SHORTWAVE DEPARTS FRIDAY NIGHT. MODELS FAIRLY CONSISTENT
IN KEEPING THE REGION DRY...SO WILL NOT CARRY ANY POPS. STRONG SFC
HIGH PRES BUILDS OVER THE AREA SATURDAY...AND THEN MOVES OFFSHORE ON
SUNDAY. SEVERAL H5 TROUGHS/SHORTWAVES WILL MOVE INTO THE SOUTHEAST
U.S. FOR THE START OF THE NEW WEEK. HOWEVER...WITH THE HIGH OVER THE
GULF OF MAINE ON MONDAY...AND THEN OVER THE CANADIAN MARITIMES ON
TUESDAY...DO NOT THINK THE SHOWERS WILL MAKE IT TO MUCH OF THE
FORECAST AREA. BEST CHANCES WILL BE FOR ISOLATED SHOWERS OVER
WESTERN PORTIONS OF THE FORECAST AREA...BUT WILL KEEP THE FORECAST
DRY.

WITH THE HIGH BUILDING INTO THE AREA SATURDAY...A MODERATING AIRMASS
WILL ALLOW TEMPS TO WARM TO NEAR AND SLIGHTLY ABOVE NORMAL LEVELS
FOR THE WEEKEND AND INTO THE MIDDLE OF THE NEW WEEK. HIGHS WILL WARM
INTO THE MID/UPPER 60S...AND POSSIBLY INTO THE LOWER 70S OVER
WESTERN AREAS. SEABREEZES LIKELY EACH AFTERNOON ACROSS COASTAL AREAS
SATURDAY AND SUNDAY...AND THEN SEABREEZE ENHANCEMENTS LIKELY INTO
THE NEW WEEK DUE TO THE COMBINATION OF LIGHT GRADIENT WINDS...WARM
SFC TEMPS...AND RELATIVELY COLDER OCEAN/SOUND WATER TEMPS.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH PRESSURE BUILDS INTO THE REGION THIS AFTERNOON AND TONIGHT.

SEA BREEZES EXPECTED DURING THE 2ND HALF OF THIS AFTN WITH TYPICAL
SEA BREEZE WIND DIRECTIONS.

...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)

KJFK FCSTER COMMENTS: WIND MOSTLY SOUTH OF 310 MAGNETIC. OCCASIONAL
GUSTS OF 16-19KT POSSIBLE BEFORE 19Z. MODERATE TO HIGH CONFIDENCE IN
SEA BREEZE OCCURRENCE. SEA BREEZE TIMING COULD BE AN HOUR OFF IN
EITHER DIRECTION.

KLGA FCSTER COMMENTS: WIND MOSTLY SOUTH OF 310 MAGNETIC. MODERATE
CONFIDENCE IN SEA BREEZE OCCURRENCE. SEA BREEZE TIMING COULD BE AN
HOUR OFF IN EITHER DIRECTION.

KEWR FCSTER COMMENTS: WIND MOSTLY SOUTH OF 310 MAGNETIC. MODERATE
CONFIDENCE IN SEA BREEZE OCCURRENCE. SEA BREEZE TIMING COULD BE AN
HOUR OFF IN EITHER DIRECTION..

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KHPN FCSTER COMMENTS: NO TACTICAL AMENDMENTS SCHEDULED AND NO
STRATEGIC AMENDMENTS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

.OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...
.FRI NIGHT-SUN...VFR.
.MON...CHC CIGS BELOW 3000FT MAINLY AM HOURS.
.TUE...CHC CIGS BELOW 3000FT MAINLY AM HOURS.

.MARINE...
NO CHANGES TO PREVIOUS HEADLINES. SEAS ON THE EXTREME EASTERN
PORTION OF ANZ350 MAY LINGER INTO THE EVE...BUT CONFIDENCE NOT
HIGH ENOUGH TO EXTEND AT THIS TIME.

A RELAXING PRESSURE GRADIENT OVER THE WATERS WILL PROMOTE SUB-SCA
CONDITIONS THEREAFTER.

HIGH PRES BUILDS OVER THE WATERS THIS WEEKEND AND WILL PERSIST
INTO THE START OF THE NEW WEEK. TRANQUIL CONDS EXPECTED ON ALL
WATERS AS A RESULT.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO EARLY NEXT WEEK.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ350-
353-355.

$$
SYNOPSIS...DS
NEAR TERM...DS
SHORT TERM...24
LONG TERM...MPS
AVIATION...JC
MARINE...24/MPS
HYDROLOGY...24/MPS

AREA FORECAST DISCUSSION...CORRECTED

NWS NEW YORK NY

1241 PM EDT THU APR 25 2013

.SYNOPSIS...
HIGH PRESSURE THEN BUILDS INTO THE REGION THROUGH THE WEEKEND AND
WILL PERSIST INTO THE MIDDLE OF NEXT WEEK.

WINDS ARE STILL EXPECTED TO DIMINISH BY THE AFTERNOON TO 10 TO 15
MPH WITH A SUNNY SKY CONDITION.

OTHERWISE...FORECAST REMAINS ON TRACK.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH PRESSURE BUILDS INTO THE REGION TODAY AND TONIGHT.

VFR. NW GUSTS SHOULD END BY AROUND 18Z. SEA BREEZES EXPECTED TO
DEVELOP DURING THE 2ND HALF OF THE AFTN FOR MOST TERMINALS WITH
TYPICAL SEA BREEZE WIND DIRECTIONS.

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)

KJFK FCSTER COMMENTS: WIND MOSTLY NORTH OF 310 MAGNETIC UNTIL AROUND
17Z...THEN SOUTH OF IT THEREAFTER. GUSTS MIGHT BE ONLY OCCASIONAL
FROM 16-18Z. MODERATE TO HIGH CONFIDENCE IN SEA BREEZE OCCURRENCE.
SEA BREEZE TIMING COULD BE AN HOUR OFF IN EITHER DIRECTION.

KLGA FCSTER COMMENTS: WIND MOSTLY NORTH OF 310 MAGNETIC UNTIL AROUND
21-22Z...THEN SOUTH OF IT THEREAFTER. GUSTS MIGHT BE ONLY OCCASIONAL
FROM 16-18Z. MODERATE CONFIDENCE IN SEA BREEZE OCCURRENCE. SEA
BREEZE TIMING COULD BE AN HOUR OFF IN EITHER DIRECTION.

KEWR FCSTER COMMENTS: WIND MOSTLY NORTH OF 310 MAGNETIC UNTIL AROUND
17-18Z...THEN SOUTH OF IT THEREAFTER. GUSTS MIGHT BE ONLY OCCASIONAL
FROM 16-18Z. MODERATE CONFIDENCE IN SEA BREEZE OCCURRENCE. SEA
BREEZE TIMING COULD BE AN HOUR OFF IN EITHER DIRECTION..

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: GUSTS MIGHT BE ONLY OCCASIONAL THROUGH 17Z.

KHPN FCSTER COMMENTS: GUSTS MIGHT BE ONLY OCCASIONAL THROUGH 17-18Z.

KISP FCSTER COMMENTS: GUSTY MIGHT BE ONLY OCCASIONAL FROM 16-18Z AND
MAY END ALTOGETHER NEAR 18Z. MODERATE TO HIGH CONFIDENCE IN SEA
BREEZE DEVELOPMENT.

.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRI-MON...VFR.

.MARINE...
SEAS WILL REMAIN ABOVE SCA LEVELS THROUGH MUCH OF THE DAY ON THE
OCEAN WATERS WITH GUSTS NEAR SCA LEVELS THIS MORNING BEHIND THE
FRONT. OCNL GUSTS UP TO 25 KT POSSIBLE FOR AN HOUR OR TWO ON
REMAINING WATERS. THEREFORE...NO CHANGES TO PREVIOUS HEADLINES.
SEAS ON THE EXTREME EASTERN PORTION OF ANZ350 MAY LINGER INTO THE
EVE...BUT CONFIDENCE NOT HIGH ENOUGH TO EXTEND AT THIS TIME.

A RELAXING PRESSURE GRADIENT OVER THE WATERS WILL PROMOTE SUB-SCA
CONDITIONS THEREAFTER.

HIGH PRES BUILDS OVER THE WATERS THIS WEEKEND AND WILL PERSIST
INTO THE START OF THE NEW WEEK. TRANQUIL CONDS EXPECTED ON ALL
WATERS AS A RESULT.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO EARLY NEXT WEEK.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ350-
353-355.

$$
SYNOPSIS...DS
NEAR TERM...DS
SHORT TERM...24
LONG TERM...MPS
AVIATION...JC
MARINE...24/MPS
HYDROLOGY...24/MPS

AREA FORECAST DISCUSSION

NWS NEW YORK NY

1240 PM EDT THU APR 25 2013

.SYNOPSIS...
HIGH PRESSURE THEN BUILDS INTO THE REGION THROUGH THE WEEKEND AND
WILL PERSIST INTO THE MIDDLE OF NEXT WEEK.

WINDS ARE STILL EXPECTED TO DIMINISH BY THE AFTERNOON TO 10 TO 15
MPH WITH A MOSTLY SUNNY SKY CONDITION.

OTHERWISE...FORECAST REMAINS ON TRACK.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH PRESSURE BUILDS INTO THE REGION TODAY AND TONIGHT.

VFR. NW GUSTS SHOULD END BY AROUND 18Z. SEA BREEZES EXPECTED TO
DEVELOP DURING THE 2ND HALF OF THE AFTN FOR MOST TERMINALS WITH
TYPICAL SEA BREEZE WIND DIRECTIONS.

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)

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: GUSTS MIGHT BE ONLY OCCASIONAL THROUGH 17Z.

KHPN FCSTER COMMENTS: GUSTS MIGHT BE ONLY OCCASIONAL THROUGH 17-18Z.

KISP FCSTER COMMENTS: GUSTY MIGHT BE ONLY OCCASIONAL FROM 16-18Z AND
MAY END ALTOGETHER NEAR 18Z. MODERATE TO HIGH CONFIDENCE IN SEA
BREEZE DEVELOPMENT.

.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRI-MON...VFR.

A RELAXING PRESSURE GRADIENT OVER THE WATERS WILL PROMOTE SUB-SCA
CONDITIONS THEREAFTER.

HIGH PRES BUILDS OVER THE WATERS THIS WEEKEND AND WILL PERSIST
INTO THE START OF THE NEW WEEK. TRANQUIL CONDS EXPECTED ON ALL
WATERS AS A RESULT.

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED INTO EARLY NEXT WEEK.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ350-
353-355.

$$
SYNOPSIS...DS
NEAR TERM...DS
SHORT TERM...24
LONG TERM...MPS
AVIATION...JC
MARINE...24/MPS
HYDROLOGY...24/MPS

AREA FORECAST DISCUSSION

NWS GOODLAND KS

230 PM MDT THU APR 25 2013

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 230 PM MDT THU APR 25 2013

EARLY AFTERNOON WV IMAGERY AND RUC ANALYSIS SHOW CLOSED LOW H5/H7
LOW OVER ARIZONA...WITH ENERGY AHEAD OF THIS FEATURE SPREADING NORTH
INTO WESTERN KS/EASTERN COLORADO. AT THE SURFACE A STRONG SURFACE
GRADIENT AS DEVELOPED IN RESPONSE TO SURFACE LOW DEEPENING OVER SOUTH
CENTRAL COLORADO.

WINDS GUSTS HAVE BEEN REPORTED THIS AFTERNOON IN THE 45-50 MPH
RANGE...AND RH VALUES HAVE DROPPED TO 15-17 PERCENT OVER EASTERN
PARTS OF THE CWA. CLOUD COVER COULD EVENTUALLY LIMIT
MIXING...HOWEVER WITH PEAK HEATING UNDERWAY I AM COMFORTABLE
KEEPING WIND ADVISORY AND RED FLAG WARNING IN PLACE WITH AFTERNOON
UPDATE.

CLOSED LOW OVER DESERT SW WILL EJECT OVER WESTERN KS TONIGHT INTO
EASTERN KS FRIDAY. WHILE H5 CENTER BECOMES MORE OF AN OPEN
WAVE...GUIDANCE IS INDICATING H7 CENTER REMAINING CLOSED AS IT
PASSES OVER KS. MODELS SHOW MID LEVEL FRONTOGENETICAL FORCING
OVERSPREADING OUR CWA THIS EVENING WITH POSSIBLE BAND FORMATION LATE
TONIGHT ON NW SIDE OF H7 LOW...POSSIBLY RESULTING IN BETTER RAIN
COVERAGE AND HIGHER RAIN TOTALS. THERE IS MINIMAL MU CAPE GENERALLY
LESS THAN 100 J/KG...HOWEVER GFS/NAM BOTH SHOW NEGATIVE THETA E
LAPSE RATES IN H8-H7 LAYER ASSOCIATED WITH MAIN AREA OF SHOWERS SO I
COULDNT RULE OUT A FEW WEAK THUNDERSTORMS WITH THIS ACTIVITY. HAVE
KEPT 50 POPS IN THE SOUTHEAST WHERE BETTER FORCING IS
ADVERTISED...WITH RAIN COMING TO AN END FOR MOSTLY LOCATIONS FRIDAY
MORNING. I KEPT SLIGHT CHANCE POPS LINGERING IN THE EASTERN PART OF
CWA TO ACCOUNT FOR POSSIBLE RAIN BAND LINGERING OVER NORTHCENTRAL
KS.

THERE WILL BE A WEAK COLD FRONT PASSING THROUGH THE CWA BY FRIDAY
MORNING...HOWEVER WITH CLEARING SKIES AND WAA IN THE AFTERNOON I
STILL EXPECT HIGHS FRIDAY TO REACH UPPER 60S/NEAR 70 IN THE WEST
(BASED ON MIXING THE LAST FEW DAYS). WARMING COULD BE LIMITED IN THE
EAST DUE TO CLOUDS/PRECIP POSSIBLY LINGERING.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 230 PM MDT THU APR 25 2013

FRIDAY NIGHT-SUNDAY...DRY WEATHER EXPECTED. WILL NEED TO WATCH
THE FAR EASTERN PORTIONS OF THE AREA FOR THUNDERSTORMS SATURDAY
AFTERNOON AS A SFC TROUGH MOVES THROUGH. THERE IS SOME WEAK
CONVERGENCE AND INSTABILITY ALONG THE WIND SHIFT WITH THIS
FEATURE...QUESTION RIGHT NOW IS HOW MUCH MOISTURE WILL BE
AVAILABLE. ANY THREAT FOR PRECIP SATURDAY AFTERNOON QUICKLY
DECREASES SATURDAY NIGHT AS THE SFC TROUGH MOVES EAST AND OUT OF
THE AREA. FOR SUNDAY GENERALLY SUNNY...MAY SEE SOME CIRRUS MOVE
DOWN FROM THE NORTH. LOWS FRIDAY NIGHT MID 30S TO LOW 40S WITH
UPPER 30S TO MID 40S SATURDAY NIGHT. HIGHS SATURDAY IN THE 70S
WITH MID 70S (WEST) TO MID 80S (EAST) SUNDAY.

SUNDAY NIGHT-MONDAY...COLD FRONT BRIEFLY PUSHES SOUTHWEST ACROSS
THE AREA SUNDAY NIGHT BEFORE RETREATING OUT OF THE AREA. NEAR OR
SLIGHTLY COOLER READINGS COMPARED TO SUNDAY EXPECTED ACROSS THE
NORTHEAST AND EAST WHERE PROXIMITY TO DEPARTING HIGH WILL BE FELT
MOST. TO THE WEST SIMILAR TO SLIGHTLY WARMER READINGS COMPARED TO
SUNDAY. LOWS MID 40S TO LOW 50S (WEST TO EAST) WITH HIGHS 75 TO 80
MONDAY.

MONDAY NIGHT-TUESDAY NIGHT...SFC TROUGH ACROSS THE AREA MONDAY NIGHT
WITH COLD FRONT MOVING THROUGH FROM THE NORTH TUESDAY. BREEZY NORTH
TO NORTHEAST WINDS TUESDAY NIGHT BEHIND THE FRONT. LOWS MONDAY NIGHT
MID 40S TO MID 50S (WEST TO EAST) WITH MID 30S TO MID 40S (WEST TO
EAST) TUESDAY NIGHT. HIGHS TUESDAY LOW 70S TO AROUND 80 (NORTH TO
SOUTH). SHOWERS AND A FEW THUNDERSTORMS POSSIBLE ACROSS THE EAST
TUESDAY AFTERNOON AHEAD OF THE FRONT. POST FRONTAL STABLE AIR MOVES
IN TUESDAY NIGHT. REMOVED MENTION OF THUNDERSTORMS BUT STILL HAVE A
CHANCE OF LIGHT RAIN.

WEDNESDAY-WEDNESDAY NIGHT...BREEZY NORTH WINDS TO CONTINUE ACROSS
THE EASTERN HALF OF THE AREA THROUGH THE DAY. SFC HIGH REMAINS OVER
THE AREA WEDNESDAY NIGHT ALLOWING FOR NEAR TO SLIGHTLY BELOW NORMAL
LOW TEMPERATURES. HIGHS IN THE MID TO UPPER 50S WITH LOWS MID TO
UPPER 30S. LOW CHANCES FOR SOME LIGHT RAIN OR RAIN SHOWERS DURING
THE DAY DECREASING DURING THE NIGHT.

THURSDAY...WARMER TEMPERATURES EXPECTED TO RETURN TO THE AREA AS
UPPER RIDGING SLOWLY MOVES IN FROM THE WEST. HIGHS MID 50S TO LOW
60S. CONTINUED LOW CHANCE FOR SOME LIGHT RAIN ACROSS THE AREA.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1126 AM MDT THU APR 25 2013

VFR CONDITIONS SHOULD PREVAIL AT BOTH KGLD AND KMCK THROUGH THE
TAF PERIOD. GUSTY WINDS THIS AFTERNOON AT BOTH TERMINALS SHOULD
DIMINISH AFTER SUNSET WITH WINDS SHIFTING TO THE W/NW BY FRIDAY
MORNING BEHIND WEAK COLD FRONT. UPPER LEVEL SYSTEM WILL BRING
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SOUTH OF INTERSTATE
70 TONIGHT THROUGH FRIDAY MORNING. WHILE KGLD HAS A BETTER CHANCE
TO SEE A SHOWER...CONFIDENCE IS TOO LOW TO INCLUDE MORE THAN
VCSH AT THIS TIME.

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 7 PM MDT /8 PM CDT/ THIS EVENING FOR
KSZ002>004-014>016-027>029-041-042.

WIND ADVISORY UNTIL 6 PM MDT /7 PM CDT/ THIS EVENING FOR
KSZ002>004-013>016-027>029-041-042.

CO...NONE.
NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ080-081.

SHORT TERM...DR
LONG TERM...99
AVIATION...DR

AREA FORECAST DISCUSSION

NWS TOPEKA KS

1155 AM CDT THU APR 25 2013

.UPDATE...
ISSUED AT 1155 AM CDT THU APR 25 2013

LATEST RAP AND NAM FORECAST SOUNDINGS SHOW THE BOUNDARY LAYER
MIXING TO NEAR 800MB. BECAUSE OF THIS HAVE BUMPED UP MAX TEMPS A
COUPLE DEGREES ALREADY...AND WE MAY END UP SEEING SOME PLACES WARM
TO AROUND 70 THIS AFTERNOON WITH GOOD INSOLATION.

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT THU APR 25 2013

ANOTHER COLD START CAN BE EXPECTED ACROSS THE REGION THIS MORNING
AS CLEAR SKIES UNDER THE AREA OF HIGH PRESSURE CAUSED TEMPERATURES
TO BOTTOM OUT IN LOW/MID 30S ACROSS MOST OF THE FORECAST AREA. WITH
THESE UNSEASONABLY COLD TEMPERATURES AND CALM WINDS IN PLACE...AREAS
OF FROST ARE EXPECTED THIS MORNING AND A FREEZE WARNING REMAINS IN
EFFECT THROUGH 9 AM THIS MORNING. TEMPERATURES ARE EXPECTED TO
QUICKLY MODERATE THROUGH THE DAY TODAY AS SOUTHERLY FLOW INCREASES
ACROSS THE REGION...WITH AFTERNOON HIGHS RISING TO WITHIN A FEW
DEGREES OF THE SEASONAL NORMALS WITH READINGS IN THE MIDDLE 60S.
THIS SOUTHERLY FLOW WILL PERSIST TODAY AND TONIGHT AS SURFACE HIGH
PRESSURE SHIFTS SOUTHEAST OF THE AREA.

EARLY THIS MORNING A SHORTWAVE TROUGH WAS LOCATED NEAR THE BAJA
PENINSULA. THIS TROUGH IS PROGGED TO TRACK NORTHEASTWARD THROUGH THE
FOUR CORNERS REGION THIS EVENING AND PROGRESS INTO THE CENTRAL
PLAINS EARLY FRIDAY MORNING. WITH THIS ADVANCING WAVE...HAVE
INCREASING POPS AFTER 06Z FRIDAY MORNING AS THERE IS A CHANCE FOR
RAIN SHOWERS TO DEVELOP ACROSS SOUTHERN KANSAS AND LIFT NORTHWARD
INTO THE FORECAST AREA. THE COMBINATION OF INCREASED CLOUD COVER
FROM THESE APPROACHING SHOWERS AND STEADY SOUTHERLY WINDS WILL HELP
KEEP OVERNIGHT TEMPERATURES RATHER WARM IN COMPARISON TO THE LAST
SEVERAL NIGHTS...WITH LOWS FRIDAY MORNING ONLY DROPPING INTO THE
MID/UPPER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 336 AM CDT THU APR 25 2013

A MID LEVEL TROUGH WILL MOVE ACROSS THE PLAINS FRIDAY THEN MOVE OFF
TO THE EAST BY EARLY SATURDAY. HIGHEST PROBABILITIES OF
PRECIPITATION CONTINUE TO BE OVER THE SOUTHERN TWO THIRDS OF THE CWA
FRIDAY THEN ACROSS THE EAST CENTRAL FRIDAY NIGHT AS THE SHORTWAVE
TROUGH PASSES THROUGH. HAVE ADJUSTED HIGH TEMPERATURES FRIDAY TO GO
A TAD COOLER OVER EAST CENTRAL AND PARTS OF NORTHEAST KANSAS. HIGHS
WILL STILL BE IN THE UPPER 50S. PRECIPITATION SHOULD COME TO AN END
FROM WEST TO EAST FRIDAY NIGHT.

CLEARING SKIES ON SATURDAY AS WELL AS RETURN FLOW ON THE BACK SIDE
OF THE SURFACE HIGH ACROSS NORTH CENTRAL KANSAS WILL SEND
TEMPERATURES INTO THE LOWER 70S WHILE THE EASTERN COUNTIES WILL SEE
HIGHS IN THE MID TO UPPER 60S.

MODELS ARE IN CONSENSUS DEVELOPING A RIDGE OVER EASTERN KANSAS
SUNDAY AND MONDAY. SENDING TEMPERATURES INTO THE MID TO UPPER
70S...AROUND 80 IN NORTH CENTRAL KANSAS SUNDAY AND MONDAY.
TEMPERATURES REMAIN IN THE 70S ON TUESDAY AHEAD OF AN APPROACHING
COLD FRONT. A DEEPENING UPPER LEVEL TROUGH WILL MOVE ACROSS THE
NORTHERN AND CENTRAL PLAINS TUESDAY AND WEDNESDAY. THIS WILL BRING
AN INCREASE IN PRECIPITATION CHANCES LATE TUESDAY INTO WEDNESDAY.
HIGH TEMPERATURES ON WEDNESDAY WILL COOL BACK INTO THE 60S BEHIND
THE COLD FRONT.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1155 AM CDT THU APR 25 2013

VFR CONDITIONS SHOULD PREVAIL THROUGH THIS EVENING. AS UPPER WAVE
APPROACHES OVERNIGHT...CIGS WILL LOWER WITH MODEL GUIDANCE
SUGGESTING MVFR CIGS MOVING IN AROUND 18Z. SINCE THIS IS TOWARDS
THE END OF THE FORECAST PERIOD...HAVE OPTED TO LEAVE OUT OF THE
TAFS FOR NOW. INSTABILITY APPEARS TO BE PRETTY LIMITED SO WILL NOT
INCLUDE A MENTION OF TS IN THE TAFS AT THIS TIME. GIVEN THE
FORCING OF THE APPROACHING UPPER WAVE AND MOISTURE ADVECTION
THROUGH THE NIGHT...THINK SCATTERED TO WIDESPREAD SHOWERS WILL
AFFECT THE TERMINALS BY 12Z FRI.

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

UPDATE...WOLTERS
SHORT TERM...HENNECKE
LONG TERM...53
AVIATION...WOLTERS

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

609 PM EDT THU APR 25 2013

.SYNOPSIS...
ISOLATED TO SCATTERED SHOWERS WILL QUICKLY SHIFT EASTWARD BEFORE
MIDNIGHT. AFTER A COOL MORNING...HIGH PRESSURE WITH SUNSHINE WILL
QUICKLY RETURN TEMPERATURES TO SEASONAL LEVELS FOR FRIDAY AND SATURDAY.

.NEAR TERM /THROUGH FRIDAY/...
AREA OF SCT SHOWERS UNDER A CROSSING SHORTWAVE...BEST EXHIBITED
VIA UAA OR RAP MDL DEPICTION OF MID LVL THERMAL TROF...WL QUICKLY
SHIFT EWD AS THE EVE PROGRESSES.

DRY HIGH PRESSURE WL BUILD OVRNGT...CLEARING THE SKY AND CALMING THE
WIND. CONDITIONS LK TO BE SUFFICIENTLY LONG FOR A CPL HOURS OF
FREEZING TEMPS OR AREAS OF FROST. FROST ADVISORY THUS REMAINS IN
EFFECT FOR AREAS WHERE SPRING HEADLINES HAVE STARTED AFTER
CONSULTATIONS WITH LOCAL GROWERS...I.E. GENERALLY WEST OF THE
RIDGES AND SOUTH OF THE PA TURNPIKE.

WITH ABUNDANT INSOLATION...FRIDAY TEMPS ARE EXPECTED TO RECOVER TO
NEAR THE SEASONAL AVERAGES.

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
DRY AND SEASONABLE WEA WL CONT AS SURFACE RIDGE SHIFTS EAST
THROUGH SATURDAY. FOR SATURDAY NIGHT AND SUNDAY...CLOUDS WILL BE
INCREASING AS A SOUTHERN STREAM SHORTWAVE MOVES TOWARD THE UPPER
OHIO VALLEY. POPS WERE LIMITED TO CHC NMBRS FOR SUNDAY AS BEST
MOISTURE AND LIFT ARE PROJECTED TO STAY SOUTH OF REGION.

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A WK SHRTWV WL MOVE ACRS THE OH VLY SUN NGT INTO MONDAY CONTG THE CHC
OF SHOWERS. HIGH PRESSURE IS THEN FORECAST TO BUILD WITH DRY WEA
AND WARMER TEMPS INTO MIDWEEK. RAIN CHCS WL INCRS THEREAFTER AS
TROFFING DVLPS OVR THE GREAT LAKES.

.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
A FAST MOVING SHORTWAVE WL CONT TO SPPRT SCT -SHRA OVR THE REGION
THIS EVE...BUT RESTRICTIONS ARE EXPECTED TO BE ISOLD. BLDG HIGH
PRES IN THE WAKE OF THAT SYS WL LEAD TO GENL VFR FOR THE RMNDR OF
THE TAF PD.

.OUTLOOK.../TONIGHT THROUGH TUESDAY/...
GENL VFR CONDS ARE EXPECTED THRU SAT NGT. SHRA AND RESULTING RESTRICTIONS
ARE PSBL SUN INTO MONDAY WITH A WK WAVE OF LOW PRES...BUT HIGH
PRES IS FORECAST TO QUICKLY REBUILD AND RTN VFR FOR MON NGT INTO
TUE.

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...FROST ADVISORY FROM 3 AM TO 9 AM EDT FRIDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...FROST ADVISORY FROM 3 AM TO 9 AM EDT FRIDAY FOR PAZ020-021-029-
031-073-075.
WV...FROST ADVISORY FROM 3 AM TO 9 AM EDT FRIDAY FOR WVZ001>004-012-
021-022.

AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

1230 PM EDT THU APR 25 2013

.SYNOPSIS...
ISSUED AT 330 AM EDT THU APR 25 2013

.UPDATE...
ISSUED AT 1159 AM EDT THU APR 25 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU APR 25 2013

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1230 PM EDT THU APR 25 2013

MVFR/VFR CONDITIONS ARE ANTICIPATED THIS AFTERNOON WITH SOME
LINGERING SHOWERS THROUGH MID AFTERNOON AT OUR SE TERMINALS (KLAN...
KJXN... KBTL AND KAZO). CONDITIONS WILL GRADUALLY IMPROVE TO VFR AT
ALL THE TERMINALS THIS EVENING AS SKIES CLEAR.

WEST WINDS WILL GUST TO AROUND 25 KTS THIS AFTN BEFORE SUBSIDING
QUICKLY THIS EVENING. WINDS WILL BACK TO THE SOUTH OVERNIGHT AND
THEN INCREASE TO 15 TO 20 KTS BY LATE FRIDAY MORNING.

.MARINE...
ISSUED AT 330 AM EDT THU APR 25 2013

GUSTY WINDS EXPECTED WITH THE PASSAGE OF THE SHORT WAVE TODAY. THIS
WILL NECESSITATE THE ISSUANCE OF A SCA.

.HYDROLOGY...
ISSUED AT 330 AM EDT THU APR 25 2013

RIVERS WILL CONTINUE TO FALL THROUGH THE WEEKEND. TODAY/S PCPN WILL
BE UNDER A TENTH AND WILL HAVE LITTLE EFFECT ON RIVER LEVELS.

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ844>849.

UPDATE...WDM
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MEADE
AVIATION...LAURENS
HYDROLOGY...93
MARINE...93

AREA FORECAST DISCUSSION...UPDATED

NWS WILMINGTON NC

527 PM EDT THU APR 25 2013

.SYNOPSIS...
A DRYING TREND IS EXPECTED FRIDAY INTO SATURDAY AS HIGH PRESSURE
REACHES DOWN FROM THE NORTH. AS THIS HIGH PRESSURE SHIFTS OFF
SHORE AN AREA OF LOW PRESSURE WILL AFFECT THE SOUTHEAST PRODUCING
AN EXTENDED PERIOD OF UNSETTLED WEATHER THROUGH THE LATTER HALF
OF THE WEEKEND INTO EARLY NEXT WEEK.

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 510 PM THURSDAY...UPDATED GRIDS DUE TO DEVELOPING COASTAL
CONVECTION. VARIOUS TEXT PRODUCTS UPDATED...INCLUDING THE HWO TO
EMPHASIZE THE SMALL HAIL AND BRIEF WIND GUSTS.

THE SHALLOW SEA BREEZE HAVING BARELY PUSHED 1 COUNTY INLAND DUE
TO STRONG WESTERLY FLOW ALOFT...THE DAYS LATE APRIL INSOLATION...
AND A BOUNDARY TRACKING SOUTHWARD WITH A NE SURGE BEHIND IT...HAVE
ALL COMBINED TO PRODUCE ISOLATED/SCATTERED CONVECTION ALONG THE
IMMEDIATE COAST OF THE ILM CWA. SVR PARAMETERS REMAIN
LACKING...HOWEVER THE STORMS HAVE PULSED UPWARDS AT TIMES
PRODUCING PEA-SIZE HAIL POSSIBLY UP TO DIME SIZE. POTENTIAL EXISTS
FOR WIND GUSTS FROM THIS ACTIVITY TO REACH 30 TO 40 MPH. MOVEMENT
OF THE ACTIVITY IS EASTWARD...AND ONCE IT REACHES THE IMMEDIATE
COASTLINE...THE ACTIVITY BASICALLY FALLS APART AS IT ENCOUNTERS
THE COOL SSTS WHICH EXHIBIT A RATHER STABLE OCEAN BASED MARINE
LAYER. WILL CONTINUE THE ACTIVITY THRU DUSK...WITH CONVECTION TO
QUICKLY CEASE THERE-AFTER.

PREVIOUS DISCUSSION..................................
AS OF 3 PM THURSDAY...AVAILABLE MOISTURE DEPICTED IN FORECAST
SOUNDINGS AND PARTIAL SUNSHINE COUPLED WITH A WEAK SEA BREEZE
MECHANISM IMPLY ISOLATED SHOWERS OR AN ISOLATED TSTM CANNOT BE
RULED OUT ENTIRELY THROUGH THE REMAINDER OF THE AFTERNOON...BUT
INTO EARLY EVENING DRYING WILL WIN OUT. FOR THIS REASON WILL
INITIATE THE TONIGHT PERIOD WITHOUT MENTIONABLE POP VALUES.
LOW-LEVEL THIN-LAYERED SATURATION MAY LINGER AROUND 2000 FT IN
ONSHORE MARITIME FLOW THROUGH THE EVENING HOURS SO WILL ADVERTISE
CLEARING MORE-SO OVERNIGHT VERSUS DIRECTLY AFTER DUSK.

ONCE CLEARING IN EARNEST COMMENCES LATER TONIGHT...RADIATIONAL
COOLING POTENTIAL WILL INCREASE. WIND HOWEVER IN THE BOUNDARY
LAYER WILL OFFSET THIS PARTIALLY. FOR THIS REASON AND CURRENT
SOIL TEMPERATURES...HAVE RAISED MINIMUM TEMPERATURES A DEGREE
OR TWO...WITH MIDDLE 40S WELL INLAND...AND UPPER 40S TO AROUND
50 ALONG THE COAST.

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...HIGH PRESSURE EXTENDING DOWN FROM THE
GREAT LAKES ON FRIDAY WILL SHIFT EAST THROUGH SATURDAY REACHING
OFF THE MID ATLANTIC COAST BY EARLY SUN MORNING. IN THE UPPER
LEVELS A RIDGE TRIES TO BUILD UP FROM THE GULF COAST BUT A
SHORTWAVE WILL RIDE OVER THE TOP OF IT FROM THE CENTRAL STATES TO
THE OHIO VALLEY BY SUNDAY MORNING. OVERALL EXPECT FRIDAY TO REMAIN
DRY WITH A FEW HIGH CLOUDS MAKING IT INTO AREA BUT BY SATURDAY
INCREASING MID TO HIGH CLOUDS WILL REACH THE AREA FROM WEATHER
ASSOCIATED WITH SHORTWAVE AND ASSOCIATED SURFACE LOW TRACKING EAST
NORTHEAST. CLOUDS WILL CONTINUE TO INCREASE THROUGH LATE SATURDAY
INTO EARLY SUNDAY AS MID TO HIGH LEVEL FLOW INCREASES OUT OF THE
WEST NORTHWEST ADVECTING CLOUDS AND MOISTURE INTO AREA. BEST LIFT
AND MOISTURE WILL REMAIN TO THE WEST OF OUR LOCAL FORECAST AREA.
CAN NOT RULE OUT SOME PCP BUT OVERALL WILL KEEP LOW END POPS
LIMITED TO WESTERN ZONES LATE SAT AFTN AND INCREASING SLIGHTLY
THROUGH SAT NIGHT AS BEST SHORTWAVE ENERGY PASSES THROUGH.

A COOLER NORTHEAST TO EASTERLY FLOW WILL PERSIST THROUGH THE
PERIOD AS WINDS VEER AROUND AS THE HIGH SHIFTS EAST REMAINING
NORTH OF AREA. THE E-NE FLOW SHOULD HELP THE SEA BREEZE PENETRATE
INLAND FARTHER...ESPECIALLY ON SATURDAY WHEN WINDS ARE MORE
EASTERLY. TEMPS WILL WARM INTO THE 70S BUT MAY GET A COUPLE OF
DEGREES SHAVING OFF AS SEA BREEZE BRINGS COOLER OCEAN AIR INLAND
THROUGH THE AFTN AND CLOUDS INCREASE TO HELP FILTER OUT THE
SUN. OVERNIGHT LOWS WILL DROP JUST BELOW 50 INLAND AND LOWER 50S
ALONG THE COAST FRI NIGHT WITH FEWER CLOUDS AND LIGHTER WINDS
EXPECTED. BY SAT NIGHT...CLOUDS AND PCP WILL KEEP TEMPS IN THE 50S
MOST PLACES.

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...SPLIT FLOW ALOFT EARLY IN THE PERIOD WILL
TRANSITION TO A BLOCKING PATTERN AS WEAK REX BLOCK SETS UP. HIGH
PRESSURE NORTH OF THE AREA WILL MAINTAIN NORTHEAST FLOW FOR MUCH OF
THE PERIOD KEEPING TEMPERATURES NEAR TO BELOW CLIMO. LOW LEVEL
NORTHEAST TO EAST FLOW AND SOUTHERLY MID LEVEL FLOW WILL KEEP PLENTY
OF MOISTURE IN THE REGION. ALTHOUGH THERE ARE NO STRONGLY FORCED
FEATURES DIURNAL HEATING...DESPITE CONSIDERABLE CLOUD COVER...AND
DEVELOPING COASTAL TROUGH NEXT WEEK WILL HELP MAINTAIN SOME RAIN
CHANCES FOR MUCH OF THE PERIOD.

.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...LOCAL WRF AND HRRR MODELS STILL DEPICT A FAIRLY DECENT
CHANCE FOR CONVECTION ALONG THE COAST...ASSOCIATED WITH THE FRONT
INTERACTING WITH THE SEA BREEZE RESULTANT. ON SATELLITE...A
NORTHEAST SURGE CAN BE OBSERVED COMING DOWN THE COAST ON VISIBLE.
THE SHOWERS SHOULD NOT BE TOO HEAVY...HOWEVER VISIBILITIES COULD
BRIEFLY GO MVFR...ALONG WITH MVFR CEILINGS. THIS EVENING...TIME
HEIGHT INDICATE SOME SORT OF A MVFR CEILING THROUGH ABOUT 06Z...THEN
DRYING AT ALL LEVELS WITH VFR CONDITIONS EXPECTED. FRIDAY...A NICE
DAY IN STORE WITH SCATTERED SKIES AND NORTHEAST FLOW...GUSTY BY MID
TO LATE MORNING.

EXTENDED OUTLOOK...VFR THROUGH SATURDAY AFTERNOON. UNSETTLED WEATHER
SATURDAY NIGHT THROUGH TUESDAY AS A STATIONARY COASTAL TROUGH GIVES
US MOSTLY CLOUDY CONDITIONS THROUGH TUESDAY WITH PERIODS OF RAIN
AND IFR CONDITIONS.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 520 PM THURSDAY...UPDATED MAINLY THE EARLY EVENING PORTION
OF THE CWF TO TAKE INTO ACCOUNT THE ISOLATED TO SCATTERED
THUNDERSTORM ACTIVITY THAT QUICKLY DECAYS ONCE IT MOVES OFF THE
MAINLAND AND INTO THE COASTAL WATERS. THE NEAR SHORE WATERS...WITHIN
5 NM OF THE COAST COULD BRIEFLY EXPERIENCE 20 TO 30 KT WIND GUSTS
AND/OR SMALL HAIL LESS THAN PEA SIZE. WITH SSTS IN THE UPPER 50S
TO LOWER 60S...AN OCEAN BASED STABLE MARINE LAYER WILL EXIST
ACROSS THE AREA WATERS. THIS STABLE LAYER HAS PROTECTED THE LOCAL
WATERS BY WEAKENING/DISSIPATING THE STRONG THUNDERSTORMS THAT MOVE
OFF THE ADJACENT MAINLAND.

PREVIOUS DISCUSSION.............................................
AS OF 3 PM THURSDAY...THERE IS STILL QUITE A BIT OF SOUTHERLY
WAVE ENERGY IN THE WATERS THAT WILL INTERACT WITH POST-FRONTAL
NE WINDS LATE THIS AFTERNOON AND OVERNIGHT...SO ALTHOUGH NO
ADVISORIES ARE IN EFFECT...THE SEA WILL HAVE A BUMPY CHARACTER
AS OPPOSING WIND-CHOP CO-MINGLES WITH SOUTHERLY LONGER PERIOD
WAVES. A FEW SHOWERS MAY DOT THE WATERS THROUGH THE EARLY EVE
BUT ANY TSTMS WILL LIKELY REMAIN CONFINED TO THE GULF STREAM.
STRENGTHENING HIGH PRESSURE MOVING INTO THE MID-ATLANTIC RGN
WILL BRING 15-20 KT NE WINDS AFTER MIDNIGHT AND AN "EXERCISE
CAUTION" HEADLINE WILL INSERTED INTO THE CWF FOR OVERNIGHT
THROUGH FRIDAY MORNING WITH 5 FOOT SEAS A DECENT BET ACROSS
OUR OUTER WATERS.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...HIGH PRESSURE WILL RIDGE DOWN FROM THE NORTH
THROUGH THE PERIOD PRODUCING A MODEST NORTHEAST FLOW ON FRIDAY
VEERING AROUND TO THE EAST AND LIGHTENING THROUGH SATURDAY AS CAA
AND GRADIENT WEAKENS. WINDS WILL START OUT 15 TO 20 KTS OUT OF THE
NORTHEAST BUT WILL DIMINISH THROUGH SAT NIGH INTO SUNDAY DOWN TO
10 TO 15 KTS.

SEAS WILL BE LOWEST JUST SOUTH OF CAPE FEAR THROUGH BRUNSWICK
COUNTY HAVING BEST PROTECTION FROM NORTHEAST FLOW...RUNNING AROUND
1 TO 2 FT. SEAS IN THE OUTER WATERS WILL BE GREATEST...UP AROUND
5 FT THROUGH SAT MORNING INTO SAT AFTN AND MAY SEE SOME 6 FOOTERS
HEADING OUT TOWARD FRYING PAN SHOALS...WITH NORTHEAST WINDS UP
CLOSE TO 20 KTS.

A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE
AT THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A
FEW PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD
AIR ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE
NORTHEAST WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL
VEERING VIA THE SEA BREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT
CRITERIA EARLY FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...NORTHEAST TO EAST FLOW ACROSS THE WATERS SUN
WILL BECOME SOUTHEAST MON/TUE AS WEAK COASTAL TROUGH TAKES SHAPE.
WIND SPEEDS WILL BE 10 TO 15 KT FOR A MAJORITY OF THE PERIOD. SEAS
WILL RUN 2 TO 4 FT THROUGH THE PERIOD.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...RGZ
NEAR TERM...DCH/MJC
SHORT TERM...RGZ
LONG TERM...III
AVIATION...SGL

AREA FORECAST DISCUSSION...UPDATED

NWS WILMINGTON NC

518 PM EDT THU APR 25 2013

PREVIOUS DISCUSSION.............................................
AS OF 3 PM THURSDAY...AVAILABLE MOISTURE DEPICTED IN FORECAST
SOUNDINGS AND PARTIAL SUNSHINE COUPLED WITH A WEAK SEA BREEZE
MECHANISM IMPLY ISOLATED SHOWERS OR AN ISOLATED TSTM CANNOT BE
RULED OUT ENTIRELY THROUGH THE REMAINDER OF THE AFTERNOON...BUT
INTO EARLY EVENING DRYING WILL WIN OUT. FOR THIS REASON WILL
INITIATE THE TONIGHT PERIOD WITHOUT MENTIONABLE POP VALUES.
LOW-LEVEL THIN-LAYERED SATURATION MAY LINGER AROUND 2000 FT IN
ONSHORE MARITIME FLOW THROUGH THE EVENING HOURS SO WILL ADVERTISE
CLEARING MORE-SO OVERNIGHT VERSUS DIRECTLY AFTER DUSK.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM THURSDAY...THERE IS STILL QUITE A BIT OF SOUTHERLY
WAVE ENERGY IN THE WATERS THAT WILL INTERACT WITH POST-FRONTAL
NE WINDS LATE THIS AFTERNOON AND OVERNIGHT...SO ALTHOUGH NO
ADVISORIES ARE IN EFFECT...THE SEA WILL HAVE A BUMPY CHARACTER
AS OPPOSING WIND-CHOP CO-MINGLES WITH SOUTHERLY LONGER PERIOD
WAVES. A FEW SHOWERS MAY DOT THE WATERS THROUGH THE EARLY EVE
BUT ANY TSTMS WILL LIKELY REMAIN CONFINED TO THE GULF STREAM.
STRENGTHENING HIGH PRESSURE MOVING INTO THE MID-ATLANTIC RGN
WILL BRING 15-20 KT NE WINDS AFTER MIDNIGHT AND AN "EXERCISE
CAUTION" HEADLINE WILL INSERTED INTO THE CWF FOR OVERNIGHT
THROUGH FRIDAY MORNING WITH 5 FOOT SEAS A DECENT BET ACROSS
OUR OUTER WATERS.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...RGZ
NEAR TERM...DCH/MJC
SHORT TERM...RGZ
LONG TERM...III
AVIATION...SGL

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

327 PM EDT THU APR 25 2013

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM THURSDAY...AVAILABLE MOISTURE DEPICTED IN FORECAST
SOUNDINGS AND PARTIAL SUNSHINE COUPLED WITH A WEAK SEA BREEZE
MECHANISM IMPLY ISOLATED SHOWERS OR AN ISOLATED TSTM CANNOT BE
RULED OUT ENTIRELY THROUGH THE REMAINDER OF THE AFTERNOON...BUT
INTO EARLY EVENING DRYING WILL WIN OUT. FOR THIS REASON WILL
INITIATE THE TONIGHT PERIOD WITHOUT MENTIONABLE POP VALUES.
LOW-LEVEL THIN-LAYERED SATURATION MAY LINGER AROUND 2000 FT IN
ONSHORE MARITIME FLOW THROUGH THE EVENING HOURS SO WILL ADVERTISE
CLEARING MORE-SO OVERNIGHT VERSUS DIRECTLY AFTER DUSK.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...HIGH PRESSURE EXTENDING DOWN FROM THE
GREAT LAKES ON FRIDAY WILL SHIFT EAST THROUGH SATURDAY REACHING
OFF THE MID ATLANTIC COAST BY EARLY SUN MORNING. IN THE UPPER
LEVELS A RIDGE TRIES TO BUILD UP FROM THE GULF COAST BUT A
SHORTWAVE WILL RIDE OVER THE TOP OF IT FROM THE CENTRAL STATES TO
THE OHIO VALLEY BY SUNDAY MORNING. OVERALL EXPECT FRIDAY TO REMAIN
DRY WITH A FEW HIGH CLOUDS MAKING IT INTO AREA BUT BY SATURDAY
INCREASING MID TO HIGH CLOUDS WILL REACH THE AREA FROM WEATHER
ASSOCIATED WITH SHORTWAVE AND ASSOCIATED SURFACE LOW TRACKING EAST
NORTHEAST. CLOUDS WILL CONTINUE TO INCREASE THROUGH LATE SATURDAY
INTO EARLY SUNDAY AS MID TO HIGH LEVEL FLOW INCREASES OUT OF THE
WEST NORTHWEST ADVECTING CLOUDS AND MOISTURE INTO AREA. BEST LIFT
AND MOISTURE WILL REMAIN TO THE WEST OF OUR LOCAL FORECAST AREA.
CAN NOT RULE OUT SOME PCP BUT OVERALL WILL KEEP LOW END POPS
LIMITED TO WESTERN ZONES LATE SAT AFTN AND INCREASING SLIGHTLY
THROUGH SAT NIGHT AS BEST SHORTWAVE ENERGY PASSES THROUGH.

A COOLER NORTHEAST TO EASTERLY FLOW WILL PERSIST THROUGH THE
PERIOD AS WINDS VEER AROUND AS THE HIGH SHIFTS EAST REMAINING
NORTH OF AREA. THE E-NE FLOW SHOULD HELP THE SEA BREEZE PENETRATE
INLAND FARTHER...ESPECIALLY ON SATURDAY WHEN WINDS ARE MORE
EASTERLY. TEMPS WILL WARM INTO THE 70S BUT MAY GET A COUPLE OF
DEGREES SHAVEN OFF AS SEA BREEZE BRINGS COOLER OCEAN AIR INLAND
THROUGH THE AFTN AND CLOUDS INCREASE TO HELP FILTER OUT THE
SUN. OVERNIGHT LOWS WILL DROP JUST BELOW 50 INLAND AND LOWER 50S
ALONG THE COAST FRI NIGHT WITH FEWER CLOUDS AND LIGHTER WINDS
EXPECTED. BY SAT NIGHT...CLOUDS AND PCP WILL KEEP TEMPS IN THE 50S
MOST PLACES.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...LOCAL WRF AND HRRR MODELS STILL DEPICT A FAIRLY DECENT
CHANCE FOR CONVECTION ALONG THE COAST...ASSOCIATED WITH THE FRONT
INTERACTING WITH THE SEA BREEZE RESULTANT. ON SATELLITE...A
NORTHEAST SURGE CAN BE OBSERVED COMING DOWN THE COAST ON VISIBLE.
THE SHOWERS SHOULD NOT BE TOO HEAVY...HOWEVER VISIBILITIES COULD
BRIEFLY GO MVFR...ALONG WITH MVFR CEILINGS. THIS EVENING...TIME
HEIGHT INDICATE SOME SORT OF A MVFR CEILING THROUGH ABOUT 06Z...THEN
DRYING AT ALL LEVELS WITH VFR CONDITIONS EXPECTED. FRIDAY...A NICE
DAY IN STORE WITH SCATTERED SKIES AND NORTHEAST FLOW...GUSTY BY MID
TO LATE MORNING.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...HIGH PRESSURE WILL RIDGE DOWN FROM THE NORTH
THROUGH THE PERIOD PRODUCING A MODEST NORTHEAST FLOW ON FRIDAY VEERING
AROUND TO THE EAST AND LIGHTENING THROUGH SATURDAY AS CAA AND
GRADIENT WEAKENS. WINDS WILL START OUT 15 TO 20 KTS OUT OF THE
NORTHEAST BUT WILL DIMINISH THROUGH SAT NIGH INTO SUNDAY DOWN TO
10 TO 15 KTS.

SEAS WILL BE LOWEST JUST SOUTH OF CAPE FEAR THROUGH BRUNSWICK
COUNTY HAVING BEST PROTECTION FROM NORTHEAST FLOW...RUNNING AROUND
1 TO 2 FT. SEAS IN THE OUTER WATERS WILL BE GREATEST...UP AROUND
5 FT THROUGH SAT MORNING INTO SAT AFTN AND MAY SEE SOME 6 FTERS
HEADING OUT TOWARD FRYING PAN SHOALS....WITH NORTHEAST WINDS UP
CLOSE TO 20 KTS.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...III
AVIATION...DL

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

137 PM EDT THU APR 25 2013

.SYNOPSIS...
COOLER AIR WILL SETTLE IN OVERNIGHT. A DRYING TREND IS EXPECTED
FRIDAY INTO SATURDAY AS HIGH PRESSURE BUILDS NORTH OF THE REGION.
RAIN IS EXPECTED SUNDAY AND MONDAY AS SEVERAL DISTURBANCES OVER THE
NORTHERN GULF TRACK OVERHEAD.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1022 AM THURSDAY...14Z/10AM SURFACE ANALYSIS SHOWS THE
FRONTAL BOUNDARY HAS JUST ABOUT CLEARED OUR FAR SOUTHERN ZONES
WITH CKI AND GGE REPORTING NW WINDS. NORTH WINDS AROUND 10 MPH
WITH TEMPERATURES IN THE MIDDLE 60S WAS COMMON THIS HOUR NORTH OF
THE BOUNDARY WITH A FEW SIGHTS HAVING AN EARLY CREST TO 70 DEGREES
AHEAD OF THE LAGGING COOL AIR ADVECTION. LATEST FORECAST SOUNDINGS
INDICATE A MOIST LAYER FROM 2500 FT EXTENDING TO 12000 FT TODAY. A
LOW-LEVEL STABLE LAYER AROUND 950 MB WILL SERVE AS A WEAK MORNING
CAP...BUT WILL PARTIALLY ERODE DURING THE AFTERNOON. SEVERAL WEAK
RIPPLES ALOFT AHEAD OF THE MAIN TROUGH AXIS UPSTREAM WITH SURFACE
WARMING AND WEAK SEA BREEZE CONVERGENCE COULD POP A FEW SHOWERS
THROUGH AFTERNOON IN THE POST FRONTAL ATMOSPHERE. ADJUSTMENTS TO
THE GRIDS WERE MADE TO ACCOMMODATE THIS POTENTIAL.

MOISTURE PUSHES OFFSHORE BY THIS EVENING WITH CLEARING OVERNIGHT.
INITIALLY VERY LIGHT WINDS AT THE SURFACE AND 1000 FEET UP WILL
PROMOTE THE DEVELOPMENT OF A STRONG RADIATIONAL INVERSION WITH
TEMPERATURES FALLING INTO THE 40S BY 2 AM INLAND. AS HIGH PRESSURE
OVER THE OHIO VALLEY STRENGTHENS AND INCREASES OUR BOUNDARY LAYER
WINDS LATE...TEMPS WILL DRIFT ONLY ANOTHER FEW DEGREES DOWN BY
DAYBREAK WITH LOWS RANGING FROM THE LOW TO MID 40S INLAND...AND
UPPER 40S TO AROUND 50 ON THE BEACHES.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...THE MAIN FEATURE FOR THE SHORT TERM PERIOD IS
THE SHORTWAVE NOW CLEARLY SEEN IN SATELLITE IMAGERY ENTERING THE
SOUTHWEST. THIS SYSTEM WILL MOVE QUICKLY ACROSS THE CONUS AS IT
TRANSITIONS FROM A CLOSED LOW TO OPEN WAVE.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...EXTENDED FORECAST REMAINS SOMEWHAT UNCERTAIN
MAINLY BEYOND SUNDAY WHEN CHANCE POPS REMAIN IN THE FORECAST VIA THE
SYSTEM NOW MOVING INTO THE SOUTHWEST. IT APPEARS A LOT OF THE
MOISTURE GENERATED BY FORECAST MODELS IS THE RESULT OF WEAK COLD AIR
DAMMING TO THE WEST. MORE SIGNIFICANT AND PROBABLY MORE REALISTIC
QPF IS ASSOCIATED WITH A LINGERING COASTAL TROUGH ACROSS MUCH OF OUR
AREA. I DID DECREASE POPS ALBEIT INCREMENTALLY MONDAY THROUGH
WEDNESDAY JUST TO REPRESENT THIS TREND. WE ARE GETTING INTO THE
SEASON WHERE MINIMAL FORCING CAN RESULT IN CONVECTION HOWEVER. NO
CHANGES TO TEMPERATURE FORECAST.

.MARINE...
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 1022 AM THURSDAY...A COLD FRONT IS CURRENTLY MOVING ACROSS
OUR COASTAL WATERS. NORTH WINDS TO INCREASE TO 15 KNOTS WITH
HIGHER GUSTS THROUGH MORNING. ISOLATED SHOWERS WILL DOT THE WATERS
TODAY BEHIND THE FRONT WITH NE WINDS AROUND 15 KT THIS AFTERNOON.
A FEW GUSTS TO 20 KT CAN BE EXPECTED. TONIGHT HIGH PRESSURE OVER
THE OHIO VALLEY WILL GAIN STRENGTH WITH ITS CENTRAL PRESSURE
INCREASING 6 MILLIBARS OVER A 12 HOUR PERIOD. THIS WILL BUILD THE
PRESSURE GRADIENT OVER THE CAROLINAS WITH THE COLD FRONT STALLING
A FEW HUNDRED MILES OFFSHORE...AND WINDS WILL REMAIN AT 15 KNOTS
WITH HIGHER GUSTS. THIS WILL BE A LONGER DURATION OF WINDIER
CONDITIONS COMPARED TO THIS MORNING...AND SEAS WILL BUILD TO 4-5
FEET AWAY FROM SHORE LATE TONIGHT.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE
AT THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A
FEW PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD AIR
ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE NORTHEAST
WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL VEERING VIA THE
SEABREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT CRITERIA EARLY
FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...WINDS AND SEAS WILL BE DICTATED BY THE
POSITION OF A COASTAL TROUGH/WARM FRONT LURKING JUST OFFSHORE. THE
SEA BREEZE...MORE LIKELY TO BE IN PLACE MONDAY WILL PLAY A ROLE AS
WELL. THE FORECAST HAS EASTERLY WINDS THROUGHOUT THE PERIOD
BASICALLY ON THE LOWER END OF A 10-15 KNOT RANGE. SEAS WILL HOVER IN
A 2-4 FT RANGE.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

NEAR TERM...TRA/MJC
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL/MJC

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

116 PM EDT THU APR 25 2013

.SYNOPSIS...
A COLD FRONT WILL PASS ACROSS THE AREA TODAY BRINGING SLIGHTLY
COOLER AIR WITH ISOLATED SHOWERS. A DRYING TREND IS EXPECTED
FRIDAY INTO SATURDAY AS HIGH PRESSURE BUILDS NORTH OF THE REGION.
RAIN IS EXPECTED SUNDAY AND MONDAY AS SEVERAL DISTURBANCES OVER
THE NORTHERN GULF TRACK OVERHEAD.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...THE MAIN FEATURE FOR THE SHORT TERM PERIOD IS
THE SHORTWAVE NOW CLEARLY SEEN IN SATELLITE IMAGERY ENTERING THE
SOUTHWEST. THIS SYSTEM WILL MOVE QUICKLY ACROSS THE CONUS AS IT
TRANSITIONS FROM A CLOSED LOW TO OPEN WAVE.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...EXTENDED FORECAST REMAINS SOMEWHAT UNCERTAIN
MAINLY BEYOND SUNDAY WHEN CHANCE POPS REMAIN IN THE FORECAST VIA THE
SYSTEM NOW MOVING INTO THE SOUTHWEST. IT APPEARS A LOT OF THE
MOISTURE GENERATED BY FORECAST MODELS IS THE RESULT OF WEAK COLD AIR
DAMMING TO THE WEST. MORE SIGNIFICANT AND PROBABLY MORE REALISTIC
QPF IS ASSOCIATED WITH A LINGERING COASTAL TROUGH ACROSS MUCH OF OUR
AREA. I DID DECREASE POPS ALBEIT INCREMENTALLY MONDAY THROUGH
WEDNESDAY JUST TO REPRESENT THIS TREND. WE ARE GETTING INTO THE
SEASON WHERE MINIMAL FORCING CAN RESULT IN CONVECTION HOWEVER. NO
CHANGES TO TEMPERATURE FORECAST.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...A DECENT NORTHEASTERLY FLOW WILL BE IN PLACE
AT THE BEGINNING OF THE PERIOD ON THE ORDER OF 10-15 KNOTS WITH A
FEW PLACES ACROSS THE OUTER WATERS SEEING JUST OVER 15. AS COLD AIR
ADVECTION WANES SO WILL THE WINDS BUT HIGH PRESSURE TO THE NORTHEAST
WILL KEEP THIS FLOW IN PLACE WITH A SLIGHT DIURNAL VEERING VIA THE
SEABREEZE. SWAN SEAS ARE JUST UNDER SMALL CRAFT CRITERIA EARLY
FRIDAY...3-5 FEET DROPPING TO 2-4 FEET BY SATURDAY.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...WINDS AND SEAS WILL BE DICTATED BY THE
POSITION OF A COASTAL TROUGH/WARM FRONT LURKING JUST OFFSHORE. THE
SEA BREEZE...MORE LIKELY TO BE IN PLACE MONDAY WILL PLAY A ROLE AS
WELL. THE FORECAST HAS EASTERLY WINDS THROUGHOUT THE PERIOD
BASICALLY ON THE LOWER END OF A 10-15 KNOT RANGE. SEAS WILL HOVER IN
A 2-4 FT RANGE.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

NEAR TERM...TRA/MJC
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL/MJC

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

140 PM EDT THU APR 25 2013

MADE LITTLE ADJUSTMENT TO THE AFTN HIGHS. KEPT THE HIGHS IN THE UPPER
30S IN THE NW...RANGING TO THE UPPER 50S IN NRN KY.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
H5 S/W SWINGING THRU THE GREAT LAKES ATTM...IS PUSHING ANOTHER
WEAK SFC FRONT/TROF ACROSS THE REGION. WITH LIFT AND CAA...AN AREA
OF VFR CLOUDS HAVE DEVELOPED AND WILL MOVE ACROSS THE TAF SITES
DURING THE FIRST PART OF THE TAF PERIOD. WINDS WILL SHIFT FROM THE
SW TO W WITH FROPA...WHICH IS CURRENTLY TIMED TO 19Z-20Z IN THE W
AND 21-22Z IN THE E. A FEW SCT SHRA MIGHT DEVELOP WITH FROPA.
KEPT A MENTION OF A VCSH IN THE CMH/LCK TAFS...WHERE THE BEST
CHANCE OF PCPN IS.

THE S/W WILL SLIP E OF THE REGION BY 00Z AND SKIES SHOULD RAPIDLY
CLEAR WHILE WINDS GO LIGHT AND VARIABLE.

BY 12Z FRIDAY...SOME H5 AND H5 MOISTURE WILL BEGIN TO WORK INTO THE
TAFS...BRINGING SOME CI.

OUTLOOK...MVFR CONDITIONS POSSIBLE SATURDAY NIGHT INTO SUNDAY.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...SITES
SHORT TERM...CONIGLIO
LONG TERM...HATZOS
AVIATION...SITES

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

556 PM EDT THU APR 25 2013

.SYNOPSIS...
A WEAKENING COLD FRONT WILL MOVE ACROSS CENTRAL PENNSYLVANIA THIS
EVENING...BRINGING SCATTERED SHOWERS TO MAINLY THE NORTHERN TIER.
HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE SOUTHWEST ON
FRIDAY...BEGINNING A SLOW WARMING TREND THAT WILL CONTINUE
THROUGH THE WEEKEND. A CHANCE FOR SHOWERS RETURNS SUNDAY INTO
MONDAY.

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
WEAKENING WAVE APPROACHING FROM THE WEST WILL SLIDE INTO NORTHERN
TIER THIS EVENING...BRINGING SCT TO LIKELY LIGHT SHOWERS.
INSTABILITY IS MARGINAL...BUT A RUMBLE OF THUNDER IS NOT OUT OF
THE QUESTION NEAR KBFD. TRAILING AND WEAKENING COLD FRONT PUSHES
THROUGH QUICKLY THIS EVENING...WITH HRRR INDICATING CHANCE FOR
QUICK SHOWER FOR WESTERN/CENTRAL SECTIONS...BUT THINK THIS IS
OVERDONE WITH DRIER AIR IN PLACE. LOWS AGAIN TURN
CHILLY...BOTTOMING OUT IN THE UPPER 20S TO UPPER 30S AS WINDS
DIMINISH AND CLOUDS THIN OUT OVERNIGHT.

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
HIGH PRESSURE BUILDS IN FROM THE SW ON FRIDAY...BRINGING PLENTY
OF SUNSHINE AND LIGHTER WINDS. HIGHS WILL TOP OUT NEAR TODAY/S
VALUES...AGAIN REMAINING ABOUT 3-5F BELOW NORMAL.

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
ZONAL UPPER FLOW PATTERN OVER NORTH AMERICA AT THE START OF THE LONG TERM
PERIOD IS FORECAST TO AMPLIFY THROUGH THE REMAINDER OF THE PERIOD.
AN UPPER RIDGE IS FORECAST TO BUILD FROM THE MID ATLANTIC STATES
NORTHWARD INTO THE CANADIAN MARITIMES...AS AN UPPER TROF DEVELOPS
OVER THE CENTRAL U.S. AS PART OF THE DEVELOPING UPPER TROF...BOTH
THE GFS AND ECMWF CLOSE OFF AN UPPER LOW CENTER OVER THE NRN/CENTRAL
PLAINS LATE NEXT WEEK...WHICH COULD HAVE FORECAST CONSEQUENCES
BEYOND THE LONG TERM PERIOD.

AT THE SFC...HIGH PRESSURE IS FORECAST TO REMAIN ANCHORED ALONG THE
NEW ENGLAND TO NOVA SCOTIA COAST THROUGH THE PERIOD. THIS WILL KEEP
PA IN GENERALLY LIGHT SERLY SFC FLOW THROUGH THE PERIOD WITH NO
SIGNIFICANT PCPN EVENTS DURING EXPECTED. HOWEVER...MODEL QPF FIELDS DEPICT
A GREAT DEAL OF LIGHT PCPN OVER AN EXPANSIVE REGION FROM NEW
ENGLAND SOUTH THRU THE CAROLINAS. WITHOUT A FOCUSING
METEOROLOGICAL MECHANISM BELIEVE IT TO BE MODEL PARAMETERIZATIONS
TRYING TO DEVELOP LIGHT PCPN ON THE TERRAIN IN THE SOUTHEAST
FLOW...AND BELIEVE THIS TO BE OVERDONE. THUS HAVE KEPT THE
MAJORITY OF THE FORECAST PERIOD DRY. THERE MAYBE SOME CHANCES FOR
ENHANCED CLOUDS AND LIGHT PCPN/DRIZZLE ON THE SE FLOW...ESPECIALLY OVER
SERN CENTRAL PA...DEPENDING GREATLY ON WHERE HIGH CENTER ENDS UP
DAY TO DAY...BUT AT THIS TIME RANGE IT TOO SOON TO TELL WHEN AND
WHERE BEYOND MINIMAL POPS.

.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
A FAST-MOVING COLD FRONT WILL BRING A FEW RAIN SHOWERS TO
NORTHWEST PA THIS EVENING...PERHAPS RESULTING IN A BRIEF VSBY
REDUCTION AT BFD. THE FRONT AND IT/S ASSOC SHOWERS SHOULD FALL
APART AS IT PRESSES SOUTH THROUGH THE REST OF CENTRAL PA LATE THIS
EVENING. SO...ALTHOUGH MANY CENTRAL PA AIRFIELDS WILL SEE A
PERIOD OF BKN STRATO-CU WITH FROPA LATE THIS EVENING...IT/S VERY
LIKELY THAT CONDS REMAIN VFR.

HIGH PRESSURE BEGINS TO BUILD IN LATE TONIGHT AND CONTINUES
THROUGH FRIDAY...BRINGING WIDESPREAD VFR CONDITIONS AND EXCELLENT
FLYING WEATHER. WINDS WILL BE 10 MPH OR LESS.

.OUTLOOK...

FRI-SAT...VFR. NO SIG WX.

SUN-MON...GENERALLY VFR. NO SIG WX. ISO/SCT SHRA POSS.

TUE...VFR. NO SIG WX.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...GARTNER
AVIATION...FITZGERALD/RXR

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

404 PM EDT THU APR 25 2013

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS ACROSS CENTRAL PA THIS AFTERNOON. AS WEAKENING WAVE
SLIDES INTO THE NORTHERN TIER FROM THE WEST...INITIALLY WINDS WILL
BECOME GUSTY FROM THE SOUTHWEST /UP TO 20 MPH/. AFTER 00Z...SCT
SHOWERS WILL IMPACT KBFD FOR SEVERAL HOURS...WITH EVEN A SMALL
CHANCE FOR AN ISO THUNDERSHOWER. ISOLATED SHOWERS WILL BE POSSIBLE
FOR A SHORT TIME THIS MID EVENING FROM KJST-KAOO-KIPT...BUT
IMPACTS SHOULD BE MINIMAL.

HIGH PRESSURE BEGINS TO BUILD IN LATE TONIGHT AND CONTINUES
THROUGH FRIDAY...BRINGING WIDESPREAD VFR CONDITIONS AND EXCELLENT
FLYING WEATHER. WINDS WILL BE 10 MPH OR LESS.

.OUTLOOK...

FRI-SAT...VFR. NO SIG WX.

SUN-MON...GENERALLY VFR. NO SIG WX. ISO/SCT SHRA POSS.

TUE...VFR. NO SIG WX.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...GARTNER
AVIATION...RXR

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

306 PM EDT THU APR 25 2013

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
BROAD CYCLONIC FLOW OVER MUCH OF NORTH AMERICA WILL BEGIN
TRANSITIONING INTO A ZONAL FLOW PATTERN AT THE START OF THE LONG
TERM PERIOD. THE UPPER FLOW PATTERN IS THEN FORECAST TO BEGIN
RE-AMPLIFYING BY LATE IN THE WEEKEND WITH A LONGWAVE RIDGE BUILDING
ALONG THE APPALACHIANS...DOWNSTREAM OF UPPER TROFFING DEVELOPING
ALONG THE NORTHERN AND CENTRAL ROCKIES.

THIS UPPER FLOW PATTERN WILL SUPPORT AN ELONGATED SFC HIGH FROM THE
CANADIAN MARITIMES SOUTHWARD INTO THE CAROLINAS THROUGH THE LONG
TERM PERIOD. THIS WILL PROVIDE NEAR TO SLIGHTLY BELOW NORMAL TEMPS
DEPENDING ON DAILY CLOUD COVER....AND NEAR TO SLIGHTLY ABOVE NORMAL
TEMPS ALONG WITH LITTLE TO IF ANY PRECIPITATION THROUGH THE PERIOD.

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS ACROSS CENTRAL PA THIS AFTERNOON. AS WEAKENING WAVE
SLIDES INTO THE NORTHERN TIER FROM THE WEST...INITIALLY WINDS WILL
BECOME GUSTY FROM THE SOUTHWEST /UP TO 20 MPH/. AFTER 00Z...SCT
SHOWERS WILL IMPACT KBFD FOR SEVERAL HOURS...WITH EVEN A SMALL
CHANCE FOR AN ISO THUNDERSHOWER. ISOLATED SHOWERS WILL BE POSSIBLE
FOR A SHORT TIME THIS MID EVENING FROM KJST-KAOO-KIPT...BUT
IMPACTS SHOULD BE MINIMAL.

HIGH PRESSURE BEGINS TO BUILD IN LATE TONIGHT AND CONTINUES
THROUGH FRIDAY...BRINGING WIDESPREAD VFR CONDTIONS AND EXCELLENT
FLYING WEATHER. WINDS WILL BE 10 MPH OR LESS.

.OUTLOOK...

FRI-SAT...VFR. NO SIF WX.

SUN-MON...GENERALLY VFR. NO SIG WX. ISO/SCT SHRA POSS.

TUE...VFR. NO SIF WX.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...DEVOIR/GARTNER
AVIATION...RXR

FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 231 PM CDT THU APR 25 2013

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN AREA OF LOW
PRESSURE MOVING INTO SE ONTARIO EARLY THIS AFTERNOON AND A SURFACE
RIDGE AXIS SHIFTING EAST INTO WESTERN WISCONSIN. PLENTY OF CLOUD
COVER LEFT OVER BEHIND THE SURFACE LOW OVER THE STATE...THANKS TO
RESIDUAL MOISTURE AND STEEP LOW LEVEL LAPSE RATES. EVEN SCATTERED
LIGHT RAIN SHOWERS OR SPRINKLES DEVELOPED OVER FAR NE WISCONSIN
EARLY THIS AFTERNOON. CLEARING IS BEGINNING TO MOVE ACROSS THE
MISSISSIPPI RIVER...AND SHOULD ACCELERATE NE THROUGH THE REST OF THE
AFTERNOON. FURTHER WEST...THE NEXT SHORTWAVE IS ENTERING THE
NORTHERN PLAINS...AND CLOUDS ARE PUSHING INTO THE DAKOTAS. PRECIP
CHANCES WITH THIS SHORTWAVE ARE THE MAIN FORECAST CONCERNS LATE
TONIGHT INTO TOMORROW MORNING.

TONIGHT...RATHER BAGGY SURFACE RIDGE AXIS WILL WORK FROM WEST TO
EAST ACROSS THE REGION LATE THIS AFTERNOON AND THIS EVENING. WITH
LOSS OF CYCLONIC FLOW AND DIURNAL HEATING...THINK CLOUDS WILL
DISSIPATE BY MID-EVENING WHICH WILL SETUP A FEW HOUR PERIOD OF
MOSTLY CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS WILL BE
CONDUCIVE FOR TEMPS TO TUMBLE FAIRLY QUICKLY THIS EVENING OVER N-C
WISCONSIN WHERE THERE REMAINS SNOW PACK. MEANWHILE
UPSTREAM...SHORTWAVE TROUGH OVER NE MONTANA WILL SWING SE TOWARDS
THE WESTERN GREAT LAKES BY MORNING. RATHER BEEFY 40-50KT LLJ WILL
DEVELOP AHEAD OF THE SHORTWAVE WITH ITS NOSE MOVING OVER
NORTH-CENTRAL WISCONSIN LATE TONIGHT. WILL INCREASE POPS INTO THE
LIKELY RANGE. TEMPS WILL BOTTOM OUT EARLY OVERNIGHT BEFORE WINDS
ALOFT PICK UP WITH THE APPROACH OF THE LLJ. WILL GO WITH MID 20S
NORTH TO MID 30S SOUTH.

FRIDAY...THE NOSE OF THE LLJ WILL PASS OVER NE WISCONSIN IN THE
12-15Z TIME PERIOD AND WILL INCREASE POPS TO LIKELY. PRECIP SHOULD
EXIT THE AREA BY MID MORNING AND WILL SEE A PARTIAL DECREASE IN
CLOUDS AS LIFT ASSOCIATED WITH THE WARM ADVECTION DEPARTS. RATHER
BAGGY 850-700MB THETAE AXIS WILL REMAIN OVERHEAD FROM CENTRAL TO
NORTHEAST WISCONSIN FOR THE REST OF THE DAY. WITH AMPLE DAYTIME
HEATING AND GOOD MIXING...SHOULD BE AMPLE TO TAP INTO THIS MOISTURE
ALOFT FOR AT LEAST PARTLY CLOUDY/PARTLY SUNNY CONDITIONS IN THE
AFTERNOON. SOME MODELS SPIT OUT PRECIP WITHIN THIS THETAE
AXIS...BUT CONVERGENCE IS VERY WEAK AND CAPE IS AROUND 100 J/KG AT
MOST. SEEMS LIKE A BETTER CHANCE FOR PRECIP TO OCCUR IS SOUTHWEST
OF THE REGION IN AN AREA OF BETTER CONVERGENCE. RESULTING SHOWERS
WILL THEN HAVE POTENTIAL TO ADVECT INTO CENTRAL OR EAST-CENTRAL
WISCONSIN LATE IN THE AFTERNOON. WILL KEEP AN ISOLATED SHOWER
MENTION BUT DROP POPS EVERYWHERE ELSE. 925MB TEMPS ARGUE FOR HIGHS
NEAR 70F...SO WILL INCREASE HIGHS A DEGREE OR TWO. HIGHS MAINLY IN
THE LOW TO MID 60S.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 231 PM CDT THU APR 25 2013

THE MAIN FCST CONCERNS INCLUDE MILDER TEMPERATURES FOR THE WEEKEND...
THEN PCPN TRENDS FOR NEXT WEEK.

A WEAKENING COLD FRONT WILL BE SAGGING SE ACROSS THE AREA ON FRIDAY
NIGHT. WILL ONLY KEEP A SLIGHT CHC OF SHOWERS DURING THE EARLY
EVENING FOR THE SE HALF OF THE FORECAST AREA...THEN DRY FOR THE
REST OF THE NIGHT. DECREASING CLOUDS...LIGHT WINDS AND LINGERING
SNOW COVER WILL SET THE STAGE FOR SOME FOG OVER NC/FAR NE WI LATE
FRIDAY NIGHT.

WENT WITH A MAINLY DRY FCST FROM SATURDAY THROUGH SUNDAY. ISOLD
SHOWERS MAY DEVELOP IN THE VCNTY OF THE OLD FRONTAL BOUNDARY ON
SATURDAY AFTERNOON...BUT CAPE IS ONLY EXPECTED TO BE AROUND 100
J/KG...SO WILL KEEP THE DRY FCST INTACT. THE NEXT FRONT IS
EXPECTED TO APPROACH OUR FAR NW COUNTIES LATE SUNDAY AFTERNOON...
A LITTLE FASTER THAN EXPECTED YESTERDAY...SO KEPT A SMALL POP
THERE. OTHERWISE...PARTLY CLOUDY SKIES AND MIXING THROUGH 800-850
MB SHOULD SUPPORT HIGHS IN THE MID 60S ON SATURDAY...AND UPPER 60S
TO LOWER 70S ON SUNDAY. THE EXCEPTION WILL BE NEAR LAKE
MICHIGAN...WHERE SOUTH WINDS WILL KEEP HIGH TEMPS 10-15 DEGREES
COOLER.

THE AFOREMENTIONED FRONT IS EXPECTED TO MOVE THROUGH GRB CWA
SUNDAY NIGHT INTO MONDAY...THEN EVENTUALLY LIFT BACK TO THE
NORTH AS A WARM FRONT MONDAY NIGHT INTO TUESDAY. SCT SHRA/ISOLD
TSRA CAN BE EXPECTED DURING THIS PERIOD. TUESDAY LOOKS LIKE THE
WARMEST DAY OF THE WEEK...WITH TEMPS APPROACHING THE MIDDLE 70S
IN CENTRAL WI.

A THIRD STRONGER COLD FRONT IS EXPECTED TO ARRIVE LATE TUES INTO
TUES NIGHT...THEN MOVE SLOWLY ACROSS THE AREA INTO WEDS OR WEDS
NIGHT. THE MOVEMENT WILL BE SLOWED BY THE DEVELOPMENT OF A MORE
AMPLIFIED SW FLOW...AS A DEEPENING UPPER TROF APPROACHES FROM THE
PLAINS. THIS FRONT SHOULD HAVE BETTER MOISTURE TO WORK WITH...AS
IT SHOULD EVENTUALLY TAP INTO THE GULF. MID-RANGE POPS SEEM
REASONABLE FOR NOW...BUT HIGHER POPS MAY EVENTUALLY BE NEEDED.
MAIN FOCUS FOR TSTMS WILL BE TUES NIGHT INTO WEDS...BUT NOT
EXPECTING ANY SEVERE WEATHER AT THIS TIME.

COOLER TEMPERATURES WILL ARRIVE WEDS INTO WEDS NGT...WITH A
MIXTURE OF RAIN/SNOW SHOWERS POSSIBLE OVER NC WI LATE WED NGT.
EXPECT MAX TEMPS TO DROP BACK BLO NORMAL AGAIN BY THURSDAY.
&&

.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 100 PM CDT THU APR 25 2013

LINGERING MVFR CLOUD DECK OVER CENTRAL AND NORTH-CENTRAL
WISCONSIN WILL TURN TO VFR AS CLOUD BASES RISE THIS AFTERNOON. THIS
WILL SETUP VFR CONDITIONS THROUGH THE REST OF THE TAF PERIOD.
HOWEVER...THERE WILL BE A FEW HOUR PERIOD OF LIGHT RAIN SHOWERS
POSSIBLE LATE TONIGHT WHEN A WARM FRONT MOVES ACROSS THE REGION.
LOW LEVEL WIND SHEAR WILL RAMP UP DURING THIS SAME PERIOD AND
CONTINUE UNTIL MID-MORNING TOMORROW.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC