Area Forecast DiscussionLatest Versions [Current][-1][-2][-3][-4][-5][-6][-7][-8][-9]
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FXUS61 KALY 210531
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
131 AM EDT TUE MAY 21 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE OVERNIGHT AND
INTO THE DAY ON A TUESDAY WITH A FRONTAL BOUNDARY BECOMING
STATIONARY ACROSS UPSTATE NEW YORK AND NORTHERN NEW ENGLAND. A
DISTURBANCE MOVING ALONG THE FRONTAL BOUNDARY WILL FOCUS SOME
SHOWERS AND THUNDERSTORMS. THE HUMID AND UNSETTLED WEATHER
CONTINUES WEDNESDAY AND THURSDAY WITH MORE CHANCES OF SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 131 AM EDT...A MILD AND MUGGY AIR MASS REMAINS IN PLACE
ACROSS THE REGION. TEMPS ARE STILL WELL INTO THE 60S....AND TDS
HAVE RISEN INTO THE 60S ALL THE WAY INTO THE ADIRONDACKS AS WELL.
A SLOW MOVING SFC BOUNDARY REMAINS DRAPED ACROSS THE NORTHERN
PORTION OF THE CWA.
THE LATEST REGIONAL MOSAIC RADAR SHOWS TWO SEPARATE LINES OF
CONVECTIVELY DRIVEN SHOWERS AND THUNDERSTORMS ACROSS CENTRAL NEW
YORK AND LAKE ONTARIO. THESE THUNDERSTORMS HAVE PERSISTED...DESPITE IT
BEING THE OVERNIGHT HOURS...DUE TO ENOUGH INSTABILITY IN PLACE. AS
THESE STORMS CONTINUE EAST-NORTHEASTWARD THEY SHOULD GRAZE OUR
WESTERN MOHAWK VALLEY AND ADIRONDACK ZONES. WHILE SFC BASED
INSTABILITY WILL BE LACKING ACROSS OUR AREA...ENOUGH ELEVATED
INSTABILITY WILL BE AROUND TO KEEP THE THUNDER RISK IN PLACE. WITH
THE PROXIMITY OF THE SFC BOUNDARY AND DECENT MID LEVEL WARM
ADVECTION...THERES NO REASON TO THINK THESE SHOWERS WILL DISSIPATE
BEFORE MOVING ACROSS THE NORTHERN PORTION OF OUR AREA. WHILE
WIDESPREAD SEVERE WX IS NOT ANTICIPATED WITH THESE STORMS...THEY
STILL MAY PRODUCE A QUICK BURST OF HEAVY RAINFALL...AND PERHAPS
SOME GUSTY WINDS TO 45 MPH. THEY SHOULD BE MOVING EAST INTO VT BY
AROUND DAYBREAK. FOR AREAS FROM THE CAPITAL REGION SOUTHWARD...IT
SHOULD REMAIN DRY OVERNIGHT WITH SOME PATCHY FOG POSSIBLE.
TEMPS WILL HOLD STEADY THROUGH THE REMAINDER OF THE NIGHT WITH
MINS IN THE UPPER 50S TO MID 60S ACROSS MUCH OF THE AREA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
TOMORROW...A SFC WAVE MOVES INTO THE UPPER MIDWEST/WRN GREAT LAKES
REGION...AS THE H500 RIDGE AXIS BEGINS TO FLATTEN OVER NY AND NEW
ENGLAND. THE FRONTAL BOUNDARY THAT STARTS OUT STATIONARY OVER THE
REGION BEGINS TO LIFT BACK NORTHWARD AS A WARM FRONT DURING THE
AFTERNOON. A MID LEVEL SHORT-WAVE APPROACHES IN THE W/NW FLOW
ALOFT. A WEAK SFC WAVE MOVES ALONG THE BOUNDARY FOCUSING SOME
SHOWERS AND THUNDERSTORMS. THE BETTER INSTABILITY LOOKS TO BE FROM
THE CAPITAL REGION SOUTH AND EAST WITH THE GFS/NAM HINTING AT SOME
SBCAPES IN THE 1000-2000+ J/KG RANGE. THERE IS MUCH LESS
INSTABILITY TO THE NORTH. THE BETTER 0-6 KM BULK /DEEP LAYER/ SHEAR IS
STRONGEST NORTH OF THE CAPITAL REGION...WITH 30 KTS OR LESS TO THE
SOUTH. THE MID LEVEL LAPSE RATES ARE NOT IDEAL OFF THE NAM WITH
GENERALLY LESS THAN 6 C/KM...WITH THE GFS HINTING AT SOME MID
LEVEL LAPSE RATES CLOSER TO 6.5C/KM SOUTH AND WEST OF KALB IN THE
LATE AFTERNOON AND EARLY EVENING. THE BEST SHEAR AND INSTABILITY
ARE OUT OF PHASE...BUT IF A CLUSTER OR COMPLEX GETS GOING WITH
THE WAVE THERE COULD BE A FEW STRONGER STORMS WITH AN ISOLATED SVR
THREAT. THE SEE TEXT FROM SPC LOOKS REASONABLE. THE UNFAVORABLE
LAPSE RATES WOULD INDICATE LESS OF A HAIL THREAT...AND A GREATER
ISOLD WIND THREAT WITH PERHAPS SOME BOWING SEGMENTS. WILL MENTION
AN ISOLD THREAT IN THE HWO. THE POPS WERE KEPT IN THE CHC CATEGORY
IN THE AFTERNOON WITH SOME LIKELY VALUES OVER THE SRN DACKS.
THE OTHER INHIBITOR FOR ANY STRONGER TO ISOLD SVR TSRAS WILL BE
THE AMOUNT OF SFC DESTABILIZATION. THE BEST CHC OF SUNSHINE
APPEARS TO BE SOUTH OF CAPITAL REGION WHERE WE HAVE THE HIGHEST
TEMPS FORECASTED WITH H850 TEMPS OF +15C TO +16C. EXPECT HIGHS IN
THE LOWER TO M80S FROM THE CAPITAL DISTRICT SOUTH IN THE
VALLEYS...AND MID AND U70S OVER THE HIGHER TERRAIN. THE SRN
DACKS...AND SRN GREENS WILL HAVE MAX TEMPS MAINLY IN THE U60S TO
M70S...WITH MID AND U70S IN THE VALLEYS.
TUE NIGHT...THE AFOREMENTIONED WAVE CONTINUES TO MOVE ALONG THE
BOUNDARY PRIOR TO MIDNIGHT WITH SHOWERS AND THUNDERSTORMS...AND
THEN THE WARM FRONT STARTS TO LIFT FURTHER NORTH AND EAST. THE
BETTER THERMAL GRADIENT...AND THE LOW-LEVEL SFC-H850 BAROCLINIC
ZONE SETS UP OVER THE NRN ZONES WHERE LIKELY POPS WERE KEPT IN FOR
SHOWERS AND A CHC OF THUNDERSTORMS. THE ELEVATED INSTABILITY WANES
AFTER 06Z WITH SHOWALTER VALUES IN THE 0 TO -2C RANGE ON THE NAM.
ANOTHER MUGGY NIGHT IS EXPECTED WITH TEMPS IN THE M50S TO M60S.
THE MAJORITY OF THE GUIDANCE AGREES THE BEST CHANCE FOR MODERATE
RAINFALL AMOUNTS OF AROUND A HALF AN INCH OR MORE WILL BE OVER THE
NRN HALF OF THE HSA.
WED-WED NIGHT...OUR FCST REFLECTS A LITTLE LULL IN THE SHOWERS AND
THUNDERSTORM ACTIVITY IN LINE WITH THE LATEST NAM DURING THE
MORNING WITH A CHANCE OF SHOWERS OVER THE NRN EXTREME...AND A
SLIGHT CHC OVER THE SRN TWO THIRDS. HENCE...WE ARE BUYING INTO THE
FCST AREA BUSTING BACK INTO THE WARM SECTOR WITH THE BOUNDARY NEAR
NRN NY AND NEW ENGLAND. H850 TEMPS RISE FURTHER TO +15C TO +17C
OVER THE ENTIRE FCST AREA...WITH POSSIBLY SOME LIGHT SW WINDS
SETTING UP IN THE BOUNDARY LAYER. FORECASTED SOME MID AND EVEN
SPOTTY U80S IN THE VALLEYS /ESPECIALLY NEAR KPOU/...WITH U70S TO
L80S OVER TH HILLS AND MTNS. ANOTHER WAVE WILL BE APPROACH FROM
THE GREAT LAKES REGION...AND A PREFRONTAL TROUGH WILL FOCUS SOME
SHOWERS AND THUNDERSTORMS IN THE LATE AFTERNOON...ESPECIALLY FOR
THE WRN ZONES. A CHC OF SHOWERS AND THUNDERSTORMS WAS INCLUDED.
PWATS WILL BE IN THE 1.25-1.67" RANGE...A COUPLE OF STANDARD
DEVIATIONS ABOVE NORMAL FOR SOME HEAVY BURSTS OF RAINFALL. SOME
MUCH NEEDED RAINFALL FOR THE HSA.
OVERNIGHT...THE QUESTION WILL BE HOW CLOSE THE FRONTAL BOUNDARY
GETS TOWARDS THE FCST AREA. THE LATEST RUN OF THE ECMWF HAS THE
FRONT AND ITS ASSOCIATED SHOWERS AND THUNDERSTORMS INTO THE NRN
TIER OF THE FCST AREA BTWN 06Z-12Z. THE GFS/NAM ARE SLOWER WITH
THEIR RESPECTIVE MODEL RUNS. FOR NOW...LIKELY POPS HAVE BEEN USED
FROM THE CAPITAL REGION NORTH AND WEST OVERNIGHT...WITH HIGH
CHANCE VALUES TO THE SOUTH. THURSDAY MORNING LOOKS LIKE THE
STICKIEST OF THE STRETCH WITH LOWER TO M60S EVERYWHERE...EXCEPT
SOME U50S OVER THE SRN GREEN MTNS AND SRN DACKS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
ACTIVE START EXPECTED TO START THE LONG TERM PERIOD AS A COLD FRONT
IS EXPECTED TO DROP SOUTHEAST FROM NEAR THE CANADIAN BORDER THURSDAY
MORNING. THE COLD FRONT IS EXPECTED TO CROSS OUR REGION THURSDAY
AFTERNOON AND EVENING AND BE SOUTHEAST OF FA FRIDAY MORNING WITH A
WAVE OF LOW PRESSURE MOVING NORTHEAST ALONG IT. THIS WAVE MAY KEEP
SHOWERS GOING ON FRIDAY. THE UPCOMING HOLIDAY WEEKEND LOOKS DRY BUT
COOL.
THURSDAY AND THURSDAY NIGHT...EXPECT A GOOD DEAL OF CLOUDS WHICH MAY
TAPER CONVECTION SOME ALTHOUGH THERE ARE QUITE A FEW FAVORABLE
FACTORS FOR AT LEAST SCATTERED THUNDERSTORMS. MLMUCAPES AHEAD OF THE
FRONT REACH 1500-2500 J/KG WITH 0-3 KM HELICITIES 60-120 M2/S2 WHILE
UPPER LEVEL JET REACHES 75-90 KTS TO THE NORTHWEST OF FA PLACING OUR
AREA IN THE RIGHT ENTRANCE REGION. THUS GENERALLY EXPECT MOSTLY
CLOUDY TO CLOUDY CONDITIONS WITH SHOWERS AND THUNDERSTORMS LIKELY
MAINLY DURING THE AFTERNOON AND EARLY EVENING HOURS WITH ACTIVITY
TAPERING TO SCATTERED SHOWERS AFTER MIDNIGHT. EXPECT HIGHS ON
THURSDAY TO BE IN THE UPPER 60S TO UPPER 70S WITH LOWS THURSDAY
NIGHT IN THE MID 40S TO UPPER 50S.
FRIDAY...EXPECT SCATTERED SHOWERS DURING THE MORNING WITH DRIER
CONDITIONS EXPECTED DURING THE AFTERNOON AS COASTAL LOW MOVES
QUICKLY DEPARTS NORTHEAST FROM SOUTHERN NEW ENGLAND COAST FRIDAY
MORNING. HIGHS ON FRIDAY ARE EXPECTED TO BE IN THE MID 50S TO AROUND
70.
FRIDAY NIGHT THROUGH SUNDAY...A SPRAWLING AREA OF HIGH PRESSURE WILL
DROP SOUTHEAST FROM CENTRAL CANADA INTO THE CENTRAL US AND BUILD
EASTWARD THROUGH THE WEEKEND. THIS WILL RESULT IN MOSTLY SUNNY TO
SUNNY SKIES AND RELATIVELY COOL CONDITIONS DURING THE DAYLIGHT HOURS
AND CLEAR TO PARTLY CLOUDY BUT CHILLY NIGHTS. HIGHS SATURDAY AND
SUNDAY ARE EXPECTED TO BE IN THE UPPER 50S TO UPPER 60S WITH LOWS IN
THE MID 30S TO MID 40S WITH SOME LOWER 30S POSSIBLE ACROSS THE
WESTERN ADIRONDACKS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
MOSTLY CLEAR SKY ACROSS THE REGION EARLY THIS MORNING...WITH A
WEAK WARM FRONT ACROSS NORTHERN NY. SOME FOG HAS FORMED AT KPSF
AND ACKNOWLEDGING IFR FOG TEMPORARILY MVFR THROUGH ABOUT 14Z AT
KPSF. A BAND OF SHOWERS AND THUNDERSTORMS OVER LAKE ONTARIO IS
MOVING EAST...AND THE SOUTHERN EDGE OF THE CONVECTION IS NEAR
KSYR. THERE IS A GUST FRONT AHEAD OF THE CONVECTION THAT IS MOVING
AT AROUND 35 KT...BUT BASED ON THE STEERING FLOW SEEN ON RADARS
ACROSS THE REGION...THIS CONVECTION SHOULD MAINLY TRACK DUE EAST.
AREA 00Z SOUNDINGS ALSO SHOW ENOUGH INSTABILITY ACROSS THE REGION TO
SUSTAIN THE CONVECTION AS IT TRACKS THROUGH EASTERN NY AND INTO
WESTERN NEW ENGLAND. HOWEVER...IT IS TIMED TO REACH THE HUDSON
VALLEY AROUND 09Z...AND WITH CONTINUED STABILIZING OF THE ATMOSPHERE
THROUGH THE EARLY MORNING HOURS...AND WEAKENING OF THE
CONVECTION...JUST INDICATING VCSH AT KGFL...KALB AND KPSF...ALTHOUGH
THE BEST CHANCE OF A SHOWER OR THUNDERSTORM WOULD BE KGFL BASED ON
RADAR TRENDS. WILL AMEND TAFS AN HOUR OR TWO PRIOR TO A SHOWER OR
THUNDERSTORM IF RADAR SUGGESTS STRENGTH OF CONVECTION AND MOVEMENT
CONTINUES.
OUTSIDE OF THESE SHOWERS AND THUNDERSTORMS...SOME PATCHY MVFR FOG
AND SOME SCATTERED VARIABLE BROKEN CLOUDS AROUND 1500 FEET ARE
POSSIBLE THROUGH ABOUT 14Z. ONCE WHATEVER RAIN TRACKS EAST OF THE
REGION...BROKEN CLOUDS ABOVE 3000 FEET TEMPORARILY SCATTERED THROUGH
THE AFTERNOON. SOME SCATTERED SHOWERS OR THUNDERSTORMS COULD
DEVELOP LATE IN THE AFTERNOON AND INTO THE EVENING...BUT NO REAL
ORGANIZED FOCUS SO LEAVING OUT ANY VCSH FOR NOW...BUT MAY BE ADDED
IN LATER TAF ISSUANCES TODAY ONCE THE CHARACTER OF CONVECTION IS
KNOWN WHEN IT FORMS.
WINDS SHOULD BE NEARLY CAL THROUGH ABOUT 14Z. WINDS SHOULD BECOME
LIGHT SOUTH TO SOUTHWEST AT LESS THAN 10 KT LATER THIS MORNING AND
CONTINUE THIS AFTERNOON AND EVENING.
OUTLOOK...
TUE NIGHT...VFR/MVFR. AT KALB AND KGFL -SHRA LIKELY WITH CHC TSRA.
AT KPSF AND KPOU CHC -SHRA/-TSRA.
WED...VFR/MVFR. CHC -SHRA/-TSRA ESPECIALLY DURING THE AFTN.
WED NIGHT...VFR/MVFR. AT KGFL AND KALB -SHRA/-TSRA LIKELY. AT
KPSF AND KPOU CHC -SHRA/-TSRA.
THU...MVFR WITH IFR POSSIBLE. -SHRA/-TSRA LIKELY.
THU NIGHT...VFR/MVFR. CHC -SHRA/-TSRA ESPECIALLY IN THE EVNG.
FRI...MAINLY VFR. CHC -SHRA MAINLY IN THE AM.
SAT...VFR. NO SIG WX.
&&
.FIRE WEATHER...
WARM AND HUMID CONDITIONS WILL CONTINUE TONIGHT WITH A
FRONTAL BOUNDARY BECOMING STATIONARY ACROSS UPSTATE NEW YORK AND
NORTHERN NEW ENGLAND. A DISTURBANCE MOVING ALONG THE FRONTAL
BOUNDARY WILL FOCUS SOME SHOWERS AND THUNDERSTORMS TOMORROW INTO
TOMORROW NIGHT. THE HUMID AND UNSETTLED WEATHER CONTINUES WEDNESDAY
AND THURSDAY WITH MORE CHANCES OF SHOWERS AND THUNDERSTORMS.
NO FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT SEVERAL DAYS
IN THE WARM AND HUMID AIR MASS. INTERMITTENT SHOWERS AND
THUNDERSTORMS ARE EXPECTED INTO FRIDAY.
THE RH VALUES WILL INCREASE TO 80 TO 100 PERCENT TONIGHT...AND
LOWER TO 55 TO 70 PERCENT TOMORROW AFTERNOON. AN EXCELLENT
RECOVERY WITH RH VALUES INCREASING TO 85 TO 100 PERCENT WEDNESDAY MORNING.
THE WINDS WILL GENERALLY BE LESS THAN 10 MPH THE NEXT FEW
DAYS...EXCEPT STRONGER GUSTS IN THUNDERSTORMS MAY BE POSSIBLE.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO SERVICE AREAS PROBLEMS ARE EXPECTED THE NEXT 5
DAYS. SOME LOCALLY HEAVY DOWNPOURS OF RAINFALL MAY OCCUR THROUGH
THE MID WEEK IN THE HUMID AIR MASS. 3-HR ZONAL FFG VALUES ARE
GENERALLY IN THE 2.4-3.1 INCH RANGE AT THIS TIME...WHICH ARE HIGH
FOR MID TO LATE MAY.
DUE TO THE SCATTERED NATURE OF THE SHOWERS AND THUNDERSTORMS...
BASIN AVERAGE QPF WILL BE HIGHLY VARIABLE THIS WEEK. THE BEST
THREAT FOR SEEING SIGNIFICANT AMOUNTS OF SHOWERS OR THUNDERSTORMS
WILL BE DURING THE MID TO LATE WEEK PERIOD /TUE NIGHT THRU THU/. THE
NERFC QPF WAS USED PRIOR TO THURSDAY WITH THE HEAVIER AMOUNTS FROM
THE CAPITAL REGION AND MOHAWK VALLEY NORTHWARD WITH ONE TO TWO INCHES
POSSIBLE IN SOME AREAS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/WASULA
NEAR TERM...FRUGIS
SHORT TERM...WASULA
LONG TERM...11
AVIATION...NAS
FIRE WEATHER...WASULA
HYDROLOGY...FRUGIS/WASULA
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