Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/24/15
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
952 AM PDT Wed Apr 22 2015
.Synopsis...
The threat of afternoon and evening showers and thunderstorms,
mainly over the mountains, will continue through the week.
&&
.Discussion...
Low clouds over the Delta, srn Sac valley and foothills slow to
lift this morning but should erode by noon. Showers and
thunderstorms will again develop over the Sierra during the
afternoon. Activity should be stronger this afternoon versus the
previous few days...but not expecting much over Cascades/Shasta
county. Short term HRRR model brings activity into the valleys
this evening...but this is not supported by other operational
models. Feel the chances for valley convection is low...especially
with stabilizing delta breeze this evening.
.Previous Discussion... Mostly cloudy skies cover most of the
interior of NorCal early this morning with plenty of mid and
upper-level moisture over the area. Lower-level moisture is quite
plentiful too as dew points across much of the area are in the
upper 40s and lower 50s. The marine layer has deepened
considerably over the past 24 hours and is now over 4000 ft in
depth and quite a bit of stratus and stratocu has spread inland or
will develop early this morning.
The rapidly deepening marine layer yesterday led to a significant
cool down across the region, and this has helped to weaken the
onshore flow as the thermal gradient from the coast to inland has
decreased. Thus, despite the cloud cover many valley areas will
see a rebound in temperatures today.
Expect we`ll see another active day of deep convection over the
mountain areas with lots of moisture (TPW approaching an inch) and
instability still present. Breaks in cloud cover should allow
sufficient surface heating to initiate thunderstorm development
by early afternoon, and presence of mid/upper COL over the region
may allow for more widespread development. Slow movement of the
storms and greater available moisture may result in some locally
heavy rain amounts later today into this evening. Given the amount
of elevated-instability and a favorable easterly steering flow, it
still looks like portions of the valley south of about I-80 will
have a non-zero chance of seeing some showers or an isolated
thunderstorm migrate down from the Sierra foothills late in the
day or this evening.
By Thursday, subtle changes develop in the pattern as we
transition to northwesterly flow with several embedded short-
waves. Normally this pattern would likely mean quite tranquil
weather for most of NorCal, but looks like there will be
sufficient moisture in the flow and lift generated from the
passing waves for a chance of showers Thursday night and again on
Saturday. We`ll continue to monitor trends.
&&
.Extended Discussion (Sunday through Wednesday)
Models build upper ridging inland over Interior NorCal Sunday into
early next week, resulting in above normal temperatures.
GFS/GEM/EC depict a shortwave trough trying to break down the
ridge a bit Tue/Wed. The GEM is the earliest on Tue, while the EC
is the latest on Wed. At any rate, all three models weaken the
trough as it makes landfall, and any chance of precip is limited
to the western Shasta County area. JClapp
&&
.Aviation...
Sct to numerous shwrs/tstms over Sierra this aftn and evening
with isolated to sct over Coastal Range.
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1033 PM PDT TUE APR 21 2015
.UPDATE...
A QUICK FORECAST UPDATE WAS SENT TO REMOVE MENTION OF THUNDER AND
REDUCE OVERALL WIND SPEEDS THROUGH THE OVERNIGHT HOURS.
WHILE THE THUNDERSTORM ACTIVITY FROM EARLIER THIS EVENING HAS
DIMINISHED, THERE CONTINUE TO BE SOME SHOWERS MOVING WESTWARD
ACROSS CHURCHILL, MINERAL, LYON AND MONO COUNTIES. THE LATEST NAM
AND HRRR KEEP SOME ACTIVITY GOING MAINLY SOUTH OF HIGHWAY 50, BUT
THERE IS A SMALL POSSIBILITY FOR SOME LATE NIGHT SPRINKLES
REACHING THE RENO AND CARSON VICINITY. LITTLE OR NO MEASURABLE
RAINFALL IS EXPECTED FROM THESE WEAK SHOWERS.
THE HIGHEST RAIN TOTALS FROM EARLIER CONVECTIVE ACTIVITY WERE
ALMOST ONE HALF INCH NEAR DONNER LAKE, AND ISOLATED REPORTS NEAR
0.25 INCH AROUND TRUCKEE AND PLUMAS-EUREKA STATE PARK. OTHERWISE,
RAIN TOTALS WERE SPOTTY AND GENERALLY 0.10 INCH OR LESS.
WHILE THE GENERAL WIND FLOW TONIGHT IS EXPECTED TO BE NORTHWEST TO
NORTH, THE SHOWERS OVER WEST CENTRAL NV HAVE PRODUCED PRODUCED
BRIEF EAST TO NORTHEAST WINDS, INCLUDING A GUST OF 30 MPH AT
FALLON AROUND 930 PM.
DUE TO THE RAIN EARLIER TODAY AROUND TRUCKEE, PATCHY FOG HAS BEGUN
TO DEVELOP AT THE KTRK AIRPORT. VSBY WILL DROP TO 1 MILE OR LESS
AT TIMES THRU EARLY WED MORNING. MJD
&&
.PREVIOUS DISCUSSION... /ISSUED 108 PM PDT TUE APR 21 2015/
SYNOPSIS...
LOW PRESSURE WILL MOVE INLAND TODAY THROUGH THURSDAY BRINGING
HIGHER CHANCES OF SHOWERS AND THUNDERSTORMS AS WELL AS COOLER
TEMPERATURES AREA WIDE. DRIER WESTERLY FLOW RETURNS BY THIS
WEEKEND DECREASING THE POTENTIAL FOR SHOWERS.
SHORT TERM...
UPPER LEVEL LOW ACROSS SOUTHERN CALIFORNIA IS SLOWLY MAKES ITS WAY
NORTH AND EAST TODAY WHILE A PACIFIC TROUGH APPROACHES THE
PACIFIC NORTHWEST. THE COMBINATION OF THESE TWO SYNOPTIC FEATURES
WILL ALLOW FOR SOME LARGE-SCALE ASCENT ACROSS THE SIERRA AND WESTERN
NEVADA OVER THE NEXT COUPLE OF DAYS. THAT COMBINED WITH DAYTIME
HEATING AND SUFFICIENT MOISTURE WILL RESULT IN ENOUGH INSTABILITY TO
PRODUCE THUNDERSTORMS THIS AFTERNOON AND EVENING AND ON WEDNESDAY AS
WELL.
RENO`S MORNING SOUNDING WAS SHOWING A FAIRLY UNSTABLE ATMOSPHERE
THIS MORNING WITH LIFTED INDICES AROUND -4. THAT ALONG WITH
EFFICIENT DAYTIME HEATING SHOULD ALLOW DEVELOPMENT OF THUNDERSTORMS
A BIT EARLIER THAN YESTERDAY. AS OF 11AM, WE ARE ALREADY SEEING SOME
DECENT CUMULUS BUILDUPS ACROSS THE REGION. MAIN CONCERNS WITH THE
STORMS TODAY WILL BE GUSTY WINDS AROUND 40 MPH, SMALL HAIL, AND
LIGHTNING. THERE WERE A COUPLE OF SMALL FIRE STARTS FROM YESTERDAY`S
LIGHTNING, SO A FEW STARTS WILL BE POSSIBLE THIS AFTERNOON AS WELL.
DROUGHT STRESSED LARGE FUELS IN THE HIGHER TERRAIN WILL BE MORE
SUSCEPTIBLE TO LIGHTNING THAN THE FINE FUELS OR GRASSES, WHICH
HAVEN`T CURED YET.
WEDNESDAY`S THUNDERSTORM COVERAGE IS NOT QUITE AS CERTAIN. ALTHOUGH
INSTABILITY AND MOISTURE APPEAR BETTER FOR THUNDERSTORM DEVELOPMENT,
RESIDUAL CLOUD COVER FROM TODAY`S STORMS OR MID LEVEL CLOUDS FROM
THE APPROACHING TROUGH COULD LIMIT THUNDERSTORMS DEVELOPING ON
WEDNESDAY.
BY THURSDAY THE UPPER LOW ACROSS SOUTHERN CA/NV WILL MOVE SOUTH AND
EAST AS THE LARGER TROUGH MOVES INTO THE PACIFIC NORTHWEST. RESIDUAL
MOISTURE AND UPPER LEVEL ASCENT WILL BE ENOUGH TO KEEP SHOWERS
ACROSS THE REGION THROUGH THE END OF THE WEEK, ESPECIALLY SOUTH OF
HIGHWAY 50. ON FRIDAY THE TROUGH DROPS SOUTH ACROSS NEVADA BRINGING
A COOLING TREND AS WELL AS SOME CHANCES FOR PRECIPITATION FOR THE
START OF THE WEEKEND. COOLER TEMPERATURES WILL ALLOW RELATIVE
HUMIDITY VALUES TO START TO RISE THROUGH THE END OF THE WEEK, EASING
FIRE WEATHER CONCERNS AND THE LIKELIHOOD OF ANY HOLDOVERS FROM
LIGHTNING. WEISHAHN
LONG TERM...SATURDAY THROUGH TUESDAY...
UPPER RIDGE WILL DOMINATE MOST OF THIS PERIOD ALTHOUGH MEDIUM
RANGE MODELS CONTINUE TO SHOW VARIATION IN THE AMPLITUDE OF RIDGE.
CONFIDENCE IS HIGH THAT THERE WILL BE NO SIGNIFICANT STORMS.
HOWEVER, DEPENDING ON AMPLITUDE OF TROUGH, THERE COULD BE A SMALL
CHANCE OF SHOWERS NEAR THE OREGON BORDER SATURDAY AND AGAIN
TUESDAY AS SHORTWAVE ENERGY PUSHES THROUGH THE PACNW AND BRUSHES
OUR AREA. IN ADDITION, THIS FLATTER SOLUTION WOULD RESULT IN
LOCALLY BREEZY CONDITIONS EARLY NEXT WEEK. OUR FORECAST WAS
ESSENTIALLY UNCHANGED AND MAINTAINS A LOW CHANCE OF SHOWERS NORTH
SATURDAY AND AGAIN TUESDAY WITH BREEZY AFTERNOON WINDS MON-TUE.
TEMPERATURES WILL REMAIN ABOVE NORMAL WITH 60S AND 70S FOR THE
MOST PART. HOHMANN
AVIATION...
SHOWERS AND THUNDERSTORMS WILL BE A BIT MORE NUMEROUS THIS AFTERNOON
AND EARLY EVENING WITH THE MAIN THREAT BEING GUSTY OUTFLOW WINDS TO
35+KT, ESPECIALLY WITH ANY STORMS THAT MOVE ONTO THE LOWER VALLEY
FLOORS. MOST OF THE EASTERN SIERRA AND FAR WESTERN NV AIRPORTS WILL
REQUIRE A VCTS WITH A 40% CHANCE OF A DIRECT HIT AT KTRK/KTVL AND
20% CHANCE AT KRNO/KCXP/KMMH. CHANCES ARE MUCH LOWER IN THE BASIN
AND RANGE AND ANY STORMS THAT MIGHT AFFECT KNFL/KLOL WOULD BE AFTER
00Z. ONE OF OUR HIGHER RESOLUTION MODELS INDICATE CONVECTION
DEVELOPING VCNTY KNFL AROUND 03Z-05Z.
THAT SAME MODEL INDICATES ANOTHER MESOSCALE GUST FRONT DEVELOPING
ALONG THE EASTERN SLOPES OF THE SIERRA 22Z-24Z, GENERALLY NEAR AND
NORTH OF HIGHWAY 50, AND THEN SPREADING EASTWARD ACROSS THE BASIN
AND RANGE DURING THE EVENING. THIS WOULD PRODUCE A 2-3 HOUR WINDOW
OF GUSTY WEST WINDS TO 25-30KT. A FEW SHOWERS MAY CONTINUE OVERNIGHT
BEFORE SHOWERS AND THUNDERSTORMS INCREASE AGAIN WEDNESDAY AFTERNOON.
HOHMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
320 AM MDT WED APR 22 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 306 AM MDT WED APR 22 2015
A WEAK UPPER LEVEL RIDGE WILL BUILD INTO THE AREA TODAY THRU TONIGHT
WITH MAINLY WLY FLOW ALOFT. AT THE SFC LOW PRES WILL WILL INTENSIFY
OVER WESTERN COLORADO ALLOWING FOR INCREASING SSE LOW LVL FLOW
ACROSS NERN CO THRU THE AFTN HOURS. MAY SEE A DENVER CYCLONE DVLP
THIS AFTN WITH A CONVERGENCE ZONE SETTING UP MAINLY TO THE SOUTH AND
EAST OF DENVER. PRECIPITABLE WATER VALUES ARE FCST TO BE SIMILAR
TO YESTERDAY OVER THE MTNS AND FOOTHILLS WITH SLIGHTLY HIGHER
VALUES DEVELOPING OVER THE PLAINS LATER THIS AFTN AND EVENING. SFC
BASED CAPES WILL GENERALLY BE 500 J/KG OR LESS EXCEPT ACROSS PARK
COUNTY AND OVER THE PALMER DIVIDE WHERE VALUES MAY BE SLIGHTLY
HIGHER.
AT THIS TIME WILL KEEP IN A CHC OF SHOWERS AND A FEW TSTMS OVER THE
HIGHER TERRAIN FOR THIS AFTN AND EVENING WITH BETTER COVERAGE
EXPECTED ALONG AND SOUTH OF I-70. AT LOWER ELEVATIONS APPEARS BEST
CHC FOR INITIAL SHOWER AND TSTM DEVELOPMENT WILL BE ALONG THE DENVER
CONVERGENCE TO THE S AND E OF DENVER SO WILL HAVE CHC POPS ACROSS
THE PALMER DIVIDE EXTENDING TOWARDS LIMON. TO THE NORTH AND NE OF
DENVER PCPN CHANCES LOOK LOWER AT THIS TIME EXTENDING INTO THE FAR
NORTHEAST CORNER. AS FOR HIGHS THIS AFTN 850-700 MB READINGS ARE
FCST TO RISE A FEW MORE DEGREES SO WILL HAVE READINGS IN THE MID
60S TO LOWER 70S OVER NERN CO.
FOR TONIGHT EXPECT LINGERING SHOWERS AND A FEW TSTMS THRU THE EARLY
EVENING HOURS HOWEVER MOST ACTIVITY SHOULD GRADUALLY END BETWEEN 03Z
AND 06Z. A FEW SHOWERS MAY LINGER OVER THE ERN PLAINS AFTER
MIDNIGHT SO WILL KEEP IN SOME LOW POPS IN THESE AREAS BETWEEN 06Z
AND 12Z.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 306 AM MDT WED APR 22 2015
ON THURSDAY...THE UPPER RIDGE AXIS WILL BE LOCATED TO THE EAST OF
COLORADO. THE FLOW ALOFT WILL BECOME SOUTHWESTERLY WITH WEAK MID
LEVEL QG ASCENT DEVELOPING. THE MDLS MAINTAIN A SURFACE TROUGH
ALONG THE FRONT RANGE. THE FORECAST SOUNDINGS FROM THE NAM12
INDICATE DECENT MOISTURE...SHEAR AND INSTABILITY IN THE AFTN FOR A
CHANCE OF SEVERE WEATHER. FORECAST CAPES AT DENVER 1800-1900 J/KG
AT AKRON...FAVORABLE SHEAR PROFILE AS WELL WITH LOW LVL SELY WINDS
TRANSITIONING TO WSWLY IN THE MID LEVELS. WITH THE LOW LEVEL SELY
WIND COMPONENT...LOOKS LIKE FAVORABLE DEVELOPMENT FOR A DENVER
CYCLONE. BEST POTENTIAL FOR SEVERE STORMS NEAR DENVER WILL BE
ALONG THIS CONVERGENCE LINE. THURSDAY NIGHT AND FRIDAY...THE MDLS
MOVE THE UPPER LOW OVER BAJA AND MOVE IT ACROSS COLORADO IN THE
12-18Z TIME FRAME. MDT QG ASCENT ASSOCIATED WITH THE TROUGH OVER
SRN AND ERN COLORADO FRIDAY MORNING. WL KEEP CHANCE OF SHOWERS
GOING IN THE MOUNTAINS THURSDAY NIGHT. WINDS ALOFT TRANSITION FM
SWLY TO NWLY FRIDAY WITH THE PASSAGE OF THE UPPER TROF AXIS.
COOLER TEMPERATURES WITH THE POTENTIAL OF SOME LIGHT SNOW IN THE
MOUNTAINS...MAYBE 1-4 INCHES IN THE 06Z TO 18Z TIME FRAME ON
FRIDAY. ACROSS THE NORTHEAST PLAINS...FAVORABLE INSTABILITY IN
SPITE OF THE COOLER TEMPERATURES. CAPES FRI AFTN COULD BE IN THE
800-1200 J/KG RANGE. THE AMS DOES STABILIZE UNDER THE INFLUENCE OF
A SHORT WAVE RIDGE ON SATURDAY. IT WILL REMAIN UNSETTLED HOWEVER
WITH THE CHC OF SHOWERS AND MAYBE AN EMBEDDED TSTM SATURDAY AFTN.
THE NEXT DEVELOPING SYSTEM IS PROGGED IMPACT COLORADO LATE
SATURDAY AND POSSIBLY INTO EARLY MONDAY. THE ECMWF...CANADIAN AND
GFS MDLS MOVE THIS TROUGH FROM THE PACIFIC NORTHWEST TO NEAR THE
FOUR CORNERS REGION BY 18Z SUNDAY THEN EAST TOWARDS THE TX
PANHANDLE BY 12Z MONDAY. AS A RESULT...THE POTENTIAL FOR ANOTHER
PERIOD OF WIDESPREAD MOUNTAIN SNOW FOR THE FRONT RANGE...WITH A
MIX OF PCPN OVER THE NORTHEAST PLAINS/PALMER DIVIDE DOES EXIST
THROUGH MONDAY MORNING. PLENTY OF UNCERTAINTY AS THE MDLS DO
DIFFER IN TIMING/TRACK ONCE THIS SYSTEM LEAVES THE FOUR CORNERS
AND MAKES ITS WAY ACROSS NEW MX. THE AMOUNT OF PCPN AGAIN
DEPENDENT ON THE TRACK OF THE TROUGH. HIGH PRESSURE AT THE SFC AND
ALOFT WILL BUILD INTO COLORADO FM THE WEST BY TUESDAY OF NEXT
WEEK.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 306 AM MDT WED APR 22 2015
WINDS EARLY THIS MORNING WERE MAINLY SLY AS A WEAK CYCLONE WAS
LOCATED TO THE NW OF DIA. BY EARLY AFTN NOT REAL CONFIDENT AS TO
WHERE THE DENVER CYCLONE WILL BE LOCATED AS IT COULD REMAIN NEAR THE
AIRPORT OR BE FURTHER EAST. BOTH THE HRRR AND RAP KEEP THE
CONVERGENCE ZN TO THE S AND E OF DIA THRU THE AFTN WITH MAINLY
NLY WINDS THRU THE AFTN HOURS. IF THIS IS THE CASE THEN THE BEST
CHANCE OF INITIAL SHOWERS/TSTMS WOULD STAY TO THE S AND E.
HOWEVER OUTFLOW BOUNDARIES COULD MOVE NORTH BY LATE AFTN AND
TRIGGER SOME ADDITIONAL ACTIVITY NR DIA SO WILL KEEP IN A TEMPO
GROUP BETWEEN 22Z AND 01Z.
OVERALL INSTABILITY IS SOMEWHAT LIMITED WHICH WOULD LIMIT
INTENSITY OF STORMS BUT THERE WILL BE SOME ERRACTIC GUSTY WINDS FM
THE STORMS. AFTER 01Z PCPN THREAT SHOULD GRADUALLY DECREASE BY
03Z. WILL TREND WINDS BACK TO DRAINAGE AFTER 03Z WHICH SHOULD
CONTINUE OVERNIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...COOPER
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS MIAMI FL
140 PM EDT WED APR 22 2015
.AVIATION...
A WEAK, SLOW MOVING COLD FRONT HAS PUSHED THROUGH THE MIAMI AREA.
THIS HAS KEPT SOME INSTABILITY OVER SOUTH FLORIDA, WHICH HAS
ALLOWED FOR SHOWERS TO PERSIST THROUGH THE DAY. MODELS ARE
INDICATING THAT THERE WILL BE ADDITIONAL INSTABILITY AND AN
ENHANCEMENT OF CONVECTION MAINLY ON THE EASTERN SIDE OF THE AREA,
AND FROM BROWARD COUNTY, SOUTH. SPECIAL UPPER AIR SOUNDINGS
PERFORMED THIS MORNING, HOWEVER, SHOW ONLY A WEAKLY UNSTABLE
ATMOSPHERE, THAT HAS ACTUALLY STABILIZED SOME SINCE 12Z. GIVEN
THIS, AND THE LACK OF ANY LIGHTNING ACROSS SOUTH FLORIDA, HAVE
REMOVED ANY MENTION OF TS FROM THE TAFS. ANOTHER SOUNDING IS BEING
DONE AT THIS TIME, AND IF THAT SHOWS INSTABILITY INCREASING, OR IF
ANY STORMS DO BEGIN TO DEVELOP, THE TS MAY BE ADDED BACK IN. WINDS
WILL CONTINUE TO VARY THROUGH THE OVERNIGHT HOURS AND PICK UP OUT
OF THE SOUTHEAST TOMORROW MORNING.
&&
.PREV DISCUSSION... /ISSUED 1005 AM EDT WED APR 22 2015/
UPDATE...
A FRONTAL BOUNDARY OVER SOUTH FLORIDA THIS MORNING WILL REMAIN
NEARLY STATIONARY THIS AFTERNOON KEEPING THE DEEP TROPICAL
MOISTURE IN PLACE OVER SOUTH FLORIDA. THE WEST AND EAST COAST SEA
BREEZES SHOULD ALSO DEVELOP THIS AFTERNOON WITH THE WEST COAST
SEA BREEZE PUSHING ACROSS THE AREA. THIS WILL KEEP THE BEST
CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON OVER THE
EASTERN AREAS OF SOUTH FLORIDA WHERE THE SEA BREEZES COLLIDE.
THEREFORE...THE POPS WILL REMAIN IN THE CHANCE TO LIKELY RANGE
WITH THE BEST COVERAGE OVER THE EASTERN AREAS OF SOUTH FLORIDA.
THERE COULD ALSO BE A FEW STRONG STORMS THIS AFTERNOON ESPECIALLY
OVER THE EASTERN AREAS OF SOUTH FLORIDA...AS A SHORT WAVE WILL BE
MOVING THROUGH THE AREA FROM THE GULF OF MEXICO. THE PRIMARY
IMPACTS FROM THE STRONGEST STORMS WILL BE GUSTY WINDS, SMALL HAIL,
HEAVY RAINFALL, AND FREQUENT LIGHTNING STRIKES.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED AT THIS TIME.
UPDATE...54/BNB
PREV DISCUSSION... /ISSUED 348 AM EDT WED APR 22 2015/
DISCUSSION...
THE RECENT UPTICK IN STRONG THUNDERSTORMS ACROSS THE REGION THIS
WEEK, IS PARTLY DUE TO THE POSITION OF A ZONAL UPPER JET FROM THE
US/MEXICO BORDER THROUGH THE FLORIDA PANHANDLE. SOUTH FLORIDA HAS
BEEN ON THE SOUTHERN EDGE OF THIS WESTERLY FLOW. THE STRENGTH OF THE
UPPER JET IS UNUSUAL, ROUGHLY 3 STANDARD DEVIATIONS ABOVE NORMAL,
AND IS DRIVEN NOT ONLY BY THE BLOCKY H5 PATTERN ACROSS NORTH
AMERICA, BUT ALSO BY THE UPPER RIDGE OVER THE CARIBBEAN WHICH HAS
DELIVERED MANY OPPRESSIVELY WARM DAYS RECENTLY. HOWEVER, TODAY
CLOUDS WILL BE A MITIGATING FACTOR WITH REGARDS TO STRONG CONVECTIVE
INITIATION, AND PERHAPS THIS IS REFLECTED IN NOT TOO IMPRESSIVE CAPE
VALUES FROM MODEL SOUNDINGS. IN CONTRAST, RUC13 SOUNDINGS DO HAVE 0-
6KM SHEAR VALUES NEAR 45 M/S AND H7-H5 LAPSE RATES 6C/KM AT MIA BY
LATE MORNING. A SHRTWV ARRIVING FROM THE GULF OVERNIGHT HAS KEPT
NORTHERN ZONES WET, AND MOISTURE WILL CONTINUE TO BE ABUNDANT SOUTH
OF THE DWINDLING FRONT OVER LAKE OKEECHOBEE. NUMEROUS SHOWERS AND
THUNDERSTORMS, NOW ENTERING THE FLORIDA STRAITS, MAY ALSO COMPLICATE
MATTERS THIS MORNING. ANY BREAKS IN THE CLOUDINESS THIS AFTERNOON,
CAN VERY WELL LEAD TO STRONG THUNDERSTORMS. MODELS FOCUSING HIGHEST
POP ACROSS BROWARD AND MIAMI-DADE TODAY. PWATS AROUND 2" AND LITTLE
DIRECTIONAL SHEAR THROUGH THE COLUMN WILL MAKE TRAINING OF STORMS
AND VERY HEAVY RAINFALL POSSIBLE.
THURSDAY LOOKS SIMILAR TO TODAY, WITH THE ONLY DIFFERENCE A SLIGHT
BACKING OF MID AND UPPER LEVEL WINDS. THE VERY SUBTLE CAA THIS
PROVIDES ALOFT MAY ENHANCE LAPSE RATES A TAD. MORNING CLOUDS MAY NOT
BE AS MUCH OF AN ISSUE AS THEY ARE TODAY, AS PRECIP TONIGHT LOOKS
LESS COMPARED TO WHAT IS HAPPENING THIS MORNING.
HIGH PRESSURE MOVING INTO THE SOUTHEASTERN CONUS SHOULD DELIVER A
SLUG OF RELATIVELY DRIER AIR IN THE MIDLEVELS ON FRIDAY. THIS
COMBINED WITH SLIGHTLY WARMING H5 TEMPS SHOULD LEAD TO LESS COVERAGE
AND STORMS FOCUSED MORE INLAND WITH CONVERGING SEA BREEZES. EVEN
DRIER AIR ARRIVES THIS WEEKEND AND PWATS CONTINUE TO SLOWLY FALL.
HOWEVER, RISING H85 TEMPS TO +19C MEAN 90F POTENTIALLY FOR ALL THE
BIG CITIES AGAIN, ESPECIALLY ON SUNDAY. THE QUIETER PATTERN SHOULD
LAST INTO EARLIER NEXT WEEK. ALTHOUGH SEVERAL DAYS AWAY, BOTH THE
GFS/ECMWF ARE BULLISH REGARDING A DEEP EASTERN TROUGH AND A NEARING
COLD FRONT AT THE END OF THE FORECAST.
MARINE...
ALTHOUGH WINDS WILL REMAIN BELOW 15 KTS AND SEAS NO GREATER THAN 3
FEET THROUGH THE FORECAST, SHOWERS AND THUNDERSTORMS MAY BE NUMEROUS
AT TIMES TODAY AND THURSDAY. SOME OF WHICH COULD BE STRONG. WIND
DIRECTION WILL BECOME INCREASINGLY SW AND W THROUGH THE WEEKEND FROM
10-15 KTS BY SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 88 72 88 / 30 50 20 20
FORT LAUDERDALE 74 87 74 88 / 40 50 20 30
MIAMI 74 90 75 89 / 40 50 20 30
NAPLES 72 86 74 87 / 10 20 10 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....10/CD
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1010 AM EDT WED APR 22 2015
.DISCUSSION...
A WEAK STATIONARY FRONT OVER THE S PENINSULA IS PROVIDING THE FOCUS
FOR POCKETS OF LIGHT RAIN STREAMING ACRS THE LAKE OKEECHOBEE REGION.
FURTHER NORTH...SAT PICS SHOW A SLUG OF SIGNIFICANTLY DRIER AIR
PUSHING INTO THE I-4 CORRIDOR...LATEST RAP ANALYSIS SHOWS H100-H70
MEAN RH VALUES AOB 40PCT...H85-H50 VALUES AOB 30PCT. MORNING
SOUNDING DEPICT THE POSITION OF THE FRONT QUITE WELL...HIGH PWAT AIR
ARND 2.0" AT KMFL...DECREASING TO ARND 1.3" AT KTBW/KXMR...THEN TO
0.8" AT KJAX/KTAE.
RAP ANALYSIS ALSO SHOWING LITTLE IN THE WAY OF MID LVL ENERGY IN THE
H85-H50 LVL VORT FIELD...A WEAKLY CONVERGENT H30-H20 LYR DESPITE THE
PRESENCE OF A 120KT ZONAL JET OVER THE DEEP SOUTH...AND H70-H50
LAPSE RATES BTWN 5.0-5.5C/KM STEEPENING FROM NORTH TO SOUTH.
AIRMASS IS A BIT TOO DRY/STABLE TO SUPPORT PRECIP MUCH FARTHER N
THAN SR60...WILL REDUCE POPS ACCORDINGLY TO AOB 20PCT. S OF SR60...
WILL KEEP SCT SHRAS/ISOLD TSRAS IN THE FCST GIVEN THE DEEPER
MOISTURE AND BETTER SFC/LOW LVL FRONTAL CONVERGENCE.
&&
.AVIATION...THRU 23/12Z
SFC WINDS: THRU 22/16Z...N/NW 4-7KTS. BTWN 22/16Z-22/19Z...BCMG E/NE
7-10KTS CONTG THRU 23/02Z. AFT 23/02Z...VRBL AOB 3KTS.
VSBYS/WX/CIGS: PREVAILING VFR ALL SITES WITH CIGS AOA FL100. BTWN
22/17Z-23/01Z...BRIEF MVFR SHRAS S OF KVRB-KSRQ.
&&
.MARINE...
FAVORABLE MARINE CONDITIONS TO CONTINUE AS A WEAK FRONTAL BOUNDARY
WASHES OUT OVER S FL AND NRN BAHAMAS. RIDGE AXIS OVER THE FL STRAITS
WILL GENERATE A LIGHT TO GENTLE WRLY BREEZE ACRS THE LCL ATLC...BCMG
E/SE NEAR THE COAST BY EARLY AFTN WITH THE FORMATION OF THE EAST
COAST SEA BREEZE. SEAS AOB 2FT NEARSHORE AND 2-3FT OFFSHORE.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...BRAGAW
LONG TERM/IMPACT WX...VOLKMER
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
1005 AM EDT WED APR 22 2015
.UPDATE...
A FRONTAL BOUNDARY OVER SOUTH FLORIDA THIS MORNING WILL REMAIN
NEARLY STATIONARY THIS AFTERNOON KEEPING THE DEEP TROPICAL
MOISTURE IN PLACE OVER SOUTH FLORIDA. THE WEST AND EAST COAST SEA
BREEZES SHOULD ALSO DEVELOP THIS AFTERNOON WITH THE WEST COAST
SEA BREEZE PUSHING ACROSS THE AREA. THIS WILL KEEP THE BEST
CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON OVER THE
EASTERN AREAS OF SOUTH FLORIDA WHERE THE SEA BREEZES COLLIDE.
THEREFORE...THE POPS WILL REMAIN IN THE CHANCE TO LIKELY RANGE
WITH THE BEST COVERAGE OVER THE EASTERN AREAS OF SOUTH FLORIDA.
THERE COULD ALSO BE A FEW STRONG STORMS THIS AFTERNOON ESPECIALLY
OVER THE EASTERN AREAS OF SOUTH FLORIDA...AS A SHORT WAVE WILL BE
MOVING THROUGH THE AREA FROM THE GULF OF MEXICO. THE PRIMARY
IMPACTS FROM THE STRONGEST STORMS WILL BE GUSTY WINDS, SMALL HAIL,
HEAVY RAINFALL, AND FREQUENT LIGHTNING STRIKES.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED AT THIS TIME.
&&
.UPDATE...54/BNB
.PREV DISCUSSION... /ISSUED 742 AM EDT WED APR 22 2015/
AVIATION...
A LINGERING BOUNDARY, THAT WAS A COLD FRONT, WILL HELP TO TRIGGER
CONVECTIVE SHOWERS AND THUNDERSTORMS THROUGH THE DAY, AND INTO THE
EVENING HOURS. EVEN SO, STILL EXPECT VFR CONDITIONS TO BE
PREDOMINATE, WITH BRIEF IFR POSSIBLE. THE IFR OCCURRENCES WOULD
BE TOO BRIEF AND TOO UNCERTAIN TO MENTION IN TAFS AT THIS TIME.
&&
PREV DISCUSSION... /ISSUED 348 AM EDT WED APR 22 2015/
DISCUSSION...
THE RECENT UPTICK IN STRONG THUNDERSTORMS ACROSS THE REGION THIS
WEEK, IS PARTLY DUE TO THE POSITION OF A ZONAL UPPER JET FROM THE
US/MEXICO BORDER THROUGH THE FLORIDA PANHANDLE. SOUTH FLORIDA HAS
BEEN ON THE SOUTHERN EDGE OF THIS WESTERLY FLOW. THE STRENGTH OF THE
UPPER JET IS UNUSUAL, ROUGHLY 3 STANDARD DEVIATIONS ABOVE NORMAL,
AND IS DRIVEN NOT ONLY BY THE BLOCKY H5 PATTERN ACROSS NORTH
AMERICA, BUT ALSO BY THE UPPER RIDGE OVER THE CARIBBEAN WHICH HAS
DELIVERED MANY OPPRESSIVELY WARM DAYS RECENTLY. HOWEVER, TODAY
CLOUDS WILL BE A MITIGATING FACTOR WITH REGARDS TO STRONG CONVECTIVE
INITIATION, AND PERHAPS THIS IS REFLECTED IN NOT TOO IMPRESSIVE CAPE
VALUES FROM MODEL SOUNDINGS. IN CONTRAST, RUC13 SOUNDINGS DO HAVE 0-
6KM SHEAR VALUES NEAR 45 M/S AND H7-H5 LAPSE RATES 6C/KM AT MIA BY
LATE MORNING. A SHRTWV ARRIVING FROM THE GULF OVERNIGHT HAS KEPT
NORTHERN ZONES WET, AND MOISTURE WILL CONTINUE TO BE ABUNDANT SOUTH
OF THE DWINDLING FRONT OVER LAKE OKEECHOBEE. NUMEROUS SHOWERS AND
THUNDERSTORMS, NOW ENTERING THE FLORIDA STRAITS, MAY ALSO COMPLICATE
MATTERS THIS MORNING. ANY BREAKS IN THE CLOUDINESS THIS AFTERNOON,
CAN VERY WELL LEAD TO STRONG THUNDERSTORMS. MODELS FOCUSING HIGHEST
POP ACROSS BROWARD AND MIAMI-DADE TODAY. PWATS AROUND 2" AND LITTLE
DIRECTIONAL SHEAR THROUGH THE COLUMN WILL MAKE TRAINING OF STORMS
AND VERY HEAVY RAINFALL POSSIBLE.
THURSDAY LOOKS SIMILAR TO TODAY, WITH THE ONLY DIFFERENCE A SLIGHT
BACKING OF MID AND UPPER LEVEL WINDS. THE VERY SUBTLE CAA THIS
PROVIDES ALOFT MAY ENHANCE LAPSE RATES A TAD. MORNING CLOUDS MAY NOT
BE AS MUCH OF AN ISSUE AS THEY ARE TODAY, AS PRECIP TONIGHT LOOKS
LESS COMPARED TO WHAT IS HAPPENING THIS MORNING.
HIGH PRESSURE MOVING INTO THE SOUTHEASTERN CONUS SHOULD DELIVER A
SLUG OF RELATIVELY DRIER AIR IN THE MIDLEVELS ON FRIDAY. THIS
COMBINED WITH SLIGHTLY WARMING H5 TEMPS SHOULD LEAD TO LESS COVERAGE
AND STORMS FOCUSED MORE INLAND WITH CONVERGING SEA BREEZES. EVEN
DRIER AIR ARRIVES THIS WEEKEND AND PWATS CONTINUE TO SLOWLY FALL.
HOWEVER, RISING H85 TEMPS TO +19C MEAN 90F POTENTIALLY FOR ALL THE
BIG CITIES AGAIN, ESPECIALLY ON SUNDAY. THE QUIETER PATTERN SHOULD
LAST INTO EARLIER NEXT WEEK. ALTHOUGH SEVERAL DAYS AWAY, BOTH THE
GFS/ECMWF ARE BULLISH REGARDING A DEEP EASTERN TROUGH AND A NEARING
COLD FRONT AT THE END OF THE FORECAST.
MARINE...
ALTHOUGH WINDS WILL REMAIN BELOW 15 KTS AND SEAS NO GREATER THAN 3
FEET THROUGH THE FORECAST, SHOWERS AND THUNDERSTORMS MAY BE NUMEROUS
AT TIMES TODAY AND THURSDAY. SOME OF WHICH COULD BE STRONG. WIND
DIRECTION WILL BECOME INCREASINGLY SW AND W THROUGH THE WEEKEND FROM
10-15 KTS BY SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 70 88 72 / 60 30 50 20
FORT LAUDERDALE 85 74 87 74 / 70 40 50 20
MIAMI 87 74 90 75 / 70 40 50 20
NAPLES 84 72 86 74 / 40 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
742 AM EDT WED APR 22 2015
.AVIATION...
A LINGERING BOUNDARY, THAT WAS A COLD FRONT, WILL HELP TO TRIGGER
CONVECTIVE SHOWERS AND THUNDERSTORMS THROUGH THE DAY, AND INTO THE
EVENING HOURS. EVEN SO, STILL EXPECT VFR CONDITIONS TO BE
PREDOMINATE, WITH BRIEF IFR POSSIBLE. THE IFR OCCURRENCES WOULD
BE TOO BRIEF AND TOO UNCERTAIN TO MENTION IN TAFS AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 348 AM EDT WED APR 22 2015/
DISCUSSION...
THE RECENT UPTICK IN STRONG THUNDERSTORMS ACROSS THE REGION THIS
WEEK, IS PARTLY DUE TO THE POSITION OF A ZONAL UPPER JET FROM THE
US/MEXICO BORDER THROUGH THE FLORIDA PANHANDLE. SOUTH FLORIDA HAS
BEEN ON THE SOUTHERN EDGE OF THIS WESTERLY FLOW. THE STRENGTH OF THE
UPPER JET IS UNUSUAL, ROUGHLY 3 STANDARD DEVIATIONS ABOVE NORMAL,
AND IS DRIVEN NOT ONLY BY THE BLOCKY H5 PATTERN ACROSS NORTH
AMERICA, BUT ALSO BY THE UPPER RIDGE OVER THE CARIBBEAN WHICH HAS
DELIVERED MANY OPPRESSIVELY WARM DAYS RECENTLY. HOWEVER, TODAY
CLOUDS WILL BE A MITIGATING FACTOR WITH REGARDS TO STRONG CONVECTIVE
INITIATION, AND PERHAPS THIS IS REFLECTED IN NOT TOO IMPRESSIVE CAPE
VALUES FROM MODEL SOUNDINGS. IN CONTRAST, RUC13 SOUNDINGS DO HAVE 0-
6KM SHEAR VALUES NEAR 45 M/S AND H7-H5 LAPSE RATES 6C/KM AT MIA BY
LATE MORNING. A SHRTWV ARRIVING FROM THE GULF OVERNIGHT HAS KEPT
NORTHERN ZONES WET, AND MOISTURE WILL CONTINUE TO BE ABUNDANT SOUTH
OF THE DWINDLING FRONT OVER LAKE OKEECHOBEE. NUMEROUS SHOWERS AND
THUNDERSTORMS, NOW ENTERING THE FLORIDA STRAITS, MAY ALSO COMPLICATE
MATTERS THIS MORNING. ANY BREAKS IN THE CLOUDINESS THIS AFTERNOON,
CAN VERY WELL LEAD TO STRONG THUNDERSTORMS. MODELS FOCUSING HIGHEST
POP ACROSS BROWARD AND MIAMI-DADE TODAY. PWATS AROUND 2" AND LITTLE
DIRECTIONAL SHEAR THROUGH THE COLUMN WILL MAKE TRAINING OF STORMS
AND VERY HEAVY RAINFALL POSSIBLE.
THURSDAY LOOKS SIMILAR TO TODAY, WITH THE ONLY DIFFERENCE A SLIGHT
BACKING OF MID AND UPPER LEVEL WINDS. THE VERY SUBTLE CAA THIS
PROVIDES ALOFT MAY ENHANCE LAPSE RATES A TAD. MORNING CLOUDS MAY NOT
BE AS MUCH OF AN ISSUE AS THEY ARE TODAY, AS PRECIP TONIGHT LOOKS
LESS COMPARED TO WHAT IS HAPPENING THIS MORNING.
HIGH PRESSURE MOVING INTO THE SOUTHEASTERN CONUS SHOULD DELIVER A
SLUG OF RELATIVELY DRIER AIR IN THE MIDLEVELS ON FRIDAY. THIS
COMBINED WITH SLIGHTLY WARMING H5 TEMPS SHOULD LEAD TO LESS COVERAGE
AND STORMS FOCUSED MORE INLAND WITH CONVERGING SEA BREEZES. EVEN
DRIER AIR ARRIVES THIS WEEKEND AND PWATS CONTINUE TO SLOWLY FALL.
HOWEVER, RISING H85 TEMPS TO +19C MEAN 90F POTENTIALLY FOR ALL THE
BIG CITIES AGAIN, ESPECIALLY ON SUNDAY. THE QUIETER PATTERN SHOULD
LAST INTO EARLIER NEXT WEEK. ALTHOUGH SEVERAL DAYS AWAY, BOTH THE
GFS/ECMWF ARE BULLISH REGARDING A DEEP EASTERN TROUGH AND A NEARING
COLD FRONT AT THE END OF THE FORECAST.
MARINE...
ALTHOUGH WINDS WILL REMAIN BELOW 15 KTS AND SEAS NO GREATER THAN 3
FEET THROUGH THE FORECAST, SHOWERS AND THUNDERSTORMS MAY BE NUMEROUS
AT TIMES TODAY AND THURSDAY. SOME OF WHICH COULD BE STRONG. WIND
DIRECTION WILL BECOME INCREASINGLY SW AND W THROUGH THE WEEKEND FROM
10-15 KTS BY SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 70 88 72 / 60 20 50 20
FORT LAUDERDALE 85 74 87 74 / 60 30 50 20
MIAMI 87 74 90 75 / 60 30 50 20
NAPLES 84 72 86 74 / 40 20 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
348 AM EDT WED APR 22 2015
.DISCUSSION...
THE RECENT UPTICK IN STRONG THUNDERSTORMS ACROSS THE REGION THIS
WEEK, IS PARTLY DUE TO THE POSITION OF A ZONAL UPPER JET FROM THE
US/MEXICO BORDER THROUGH THE FLORIDA PANHANDLE. SOUTH FLORIDA HAS
BEEN ON THE SOUTHERN EDGE OF THIS WESTERLY FLOW. THE STRENGTH OF THE
UPPER JET IS UNUSUAL, ROUGHLY 3 STANDARD DEVIATIONS ABOVE NORMAL,
AND IS DRIVEN NOT ONLY BY THE BLOCKY H5 PATTERN ACROSS NORTH
AMERICA, BUT ALSO BY THE UPPER RIDGE OVER THE CARIBBEAN WHICH HAS
DELIVERED MANY OPPRESSIVELY WARM DAYS RECENTLY. HOWEVER, TODAY
CLOUDS WILL BE A MITIGATING FACTOR WITH REGARDS TO STRONG CONVECTIVE
INITIATION, AND PERHAPS THIS IS REFLECTED IN NOT TOO IMPRESSIVE CAPE
VALUES FROM MODEL SOUNDINGS. IN CONTRAST, RUC13 SOUNDINGS DO HAVE 0-
6KM SHEAR VALUES NEAR 45 M/S AND H7-H5 LAPSE RATES 6C/KM AT MIA BY
LATE MORNING. A SHRTWV ARRIVING FROM THE GULF OVERNIGHT HAS KEPT
NORTHERN ZONES WET, AND MOISTURE WILL CONTINUE TO BE ABUNDANT SOUTH
OF THE DWINDLING FRONT OVER LAKE OKEECHOBEE. NUMEROUS SHOWERS AND
THUNDERSTORMS, NOW ENTERING THE FLORIDA STRAITS, MAY ALSO COMPLICATE
MATTERS THIS MORNING. ANY BREAKS IN THE CLOUDINESS THIS AFTERNOON,
CAN VERY WELL LEAD TO STRONG THUNDERSTORMS. MODELS FOCUSING HIGHEST
POP ACROSS BROWARD AND MIAMI-DADE TODAY. PWATS AROUND 2" AND LITTLE
DIRECTIONAL SHEAR THROUGH THE COLUMN WILL MAKE TRAINING OF STORMS
AND VERY HEAVY RAINFALL POSSIBLE.
THURSDAY LOOKS SIMILAR TO TODAY, WITH THE ONLY DIFFERENCE A SLIGHT
BACKING OF MID AND UPPER LEVEL WINDS. THE VERY SUBTLE CAA THIS
PROVIDES ALOFT MAY ENHANCE LAPSE RATES A TAD. MORNING CLOUDS MAY NOT
BE AS MUCH OF AN ISSUE AS THEY ARE TODAY, AS PRECIP TONIGHT LOOKS
LESS COMPARED TO WHAT IS HAPPENING THIS MORNING.
HIGH PRESSURE MOVING INTO THE SOUTHEASTERN CONUS SHOULD DELIVER A
SLUG OF RELATIVELY DRIER AIR IN THE MIDLEVELS ON FRIDAY. THIS
COMBINED WITH SLIGHTLY WARMING H5 TEMPS SHOULD LEAD TO LESS COVERAGE
AND STORMS FOCUSED MORE INLAND WITH CONVERGING SEA BREEZES. EVEN
DRIER AIR ARRIVES THIS WEEKEND AND PWATS CONTINUE TO SLOWLY FALL.
HOWEVER, RISING H85 TEMPS TO +19C MEAN 90F POTENTIALLY FOR ALL THE
BIG CITIES AGAIN, ESPECIALLY ON SUNDAY. THE QUIETER PATTERN SHOULD
LAST INTO EARLIER NEXT WEEK. ALTHOUGH SEVERAL DAYS AWAY, BOTH THE
GFS/ECMWF ARE BULLISH REGARDING A DEEP EASTERN TROUGH AND A NEARING
COLD FRONT AT THE END OF THE FORECAST.
&&
.MARINE...
ALTHOUGH WINDS WILL REMAIN BELOW 15 KTS AND SEAS NO GREATER THAN 3
FEET THROUGH THE FORECAST, SHOWERS AND THUNDERSTORMS MAY BE NUMEROUS
AT TIMES TODAY AND THURSDAY. SOME OF WHICH COULD BE STRONG. WIND
DIRECTION WILL BECOME INCREASINGLY SW AND W THROUGH THE WEEKEND FROM
10-15 KTS BY SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 70 88 72 / 60 10 50 20
FORT LAUDERDALE 85 74 87 74 / 70 20 50 20
MIAMI 87 74 90 75 / 70 30 50 20
NAPLES 84 72 86 74 / 40 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
701 PM CDT THU APR 23 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 342 PM CDT THU APR 23 2015
FORECAST ISSUES IN THE SHORT TERM CENTER AROUND THUNDERSTORM CHANCES
TONIGHT AND FRIDAY AND THE SEVERE WEATHER POTENTIAL ASSOCIATED WITH
THE STORMS.
THE ATMOSPHERE OVER THE HIGH PLAINS OF EASTERN COLORADO AND FAR WESTERN
KANSAS WAS BECOMING MODERATELY UNSTABLE WITH DAYTIME HEATING THIS
AFTERNOON. A SURFACE TROUGH OF LOW PRESSURE STRENGTHENING OVER EASTERN
COLORADO WAS ALSO PROVIDING SOME LOW LEVEL CONVERGENCE AND TRIGGERING
WIDELY SCATTERED THUNDERSTORMS. SPC MESOANALYSIS SHOWS 30- 40 KNOTS
OF SHEAR IN THE 0-6 KM LAYER BUT ABOVE THIS LAYER, STRONGER SHEAR
WAS IN PLACE IN THE PRESENCE OF A STRONG SUBTROPICAL JET. THE STORMS
OVER EASTERN COLORADO WILL BE IN A FAVORABLE ENVIRONMENT TO BECOME
ROTATING SUPERCELLS. GIVEN THE STRONG EVACUATION ALOFT, LARGE HAIL
WILL BE A GOOD POSSIBILITY. THE HRRR MODEL HAS BEEN VERY CONSISTENT
WITH THUNDERSTORMS MOVING INTO WESTERN KANSAS AROUND JOHNSON AND
SYRACUSE AND POINTS NORTH THIS EVENING AROUND 23Z-01Z AND HAVE
KEPT THE BEST CHANCES IN THAT AREA EARLY THIS EVENING. AS THE
NIGHT CONTINUES, AN AREA OF THUNDERSTORMS COULD CONTINUE TO DEVELOP
OVER WEST CENTRAL AND NORTHWEST KANSAS AS A WEAK MID LEVEL DISTURBANCE
ALONG WITH THE LEFT EXIT REGION OF AN UPPER LEVEL SPEED MAX MOVES
OVER THE AREA. THE MODELS ALSO SHOW INCREASING SOUTHERLY FLOW AT THE
850 MILLIBAR LEVEL WHICH COULD ALSO HELP SUSTAIN THUNDERSTORMS THROUGH
THE NIGHT. THE BEST CHANCE FOR STORMS SHOULD BE ALONG AND/OR NORTH
OF HIGHWAY 50 AND 156. THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH
SOMEWHAT AFTER DARK BUT CAN`T RULE OUT THE POSSIBILITY OF A FEW
ELEVATED HAILERS. CHANCES FOR STORMS WILL DIMINISH LATER TONIGHT
AS THE MID/UPPER LEVEL SUPPORT MOVES EAST OF THE AREA.
ON FRIDAY, THE MAIN UPPER TROUGH MOVES OUT INTO THE CENTRAL AND
SOUTHERN PLAINS. THE MODELS DEVELOP A SURFACE LOW OVER WEST CENTRAL
KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW. BY FRIDAY
AFTERNOON THE LOW WILL BE PROGRESSING EAST WHILE A DRYLINE PUSHES
EAST ACROSS SOUTHWEST THROUGH SOUTH CENTRAL KANSAS. THE UPPER LEVEL
JET PROPAGATES EAST THROUGH THE DAY. THE 18Z MODELS ARE NOW LOOKING
LESS FAVORABLE FOR SEVERE POTENTIAL AS THE BETTER 0-6 KM SHEAR WILL
BE TO THE SOUTH AND EAST OF THE DODGE CITY CWFA DURING THE MID/LATE
AFTERNOON HOURS. WITH SOME GOOD INSTABILITY OVER THE NORTHERN AND
EASTERN SECTIONS OF THE CWA, THERE WILL STILL BE POTENTIAL FOR
SOME SEVERE STORMS AS WELL AS THE POTENTIAL FOR TORNADOES ALONG
AND NORTH OF THE FRONTAL BOUNDARY OVER CENTRAL KANSAS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 PM CDT THU APR 23 2015
THE WEAK UPPER LEVEL LOW WILL CONTINUE TO MOVE EASTWARD ACROSS
THE KS/NE BORDER FRIDAY NIGHT. THIS WILL HELP PUSH A SURFACE LOW
AND ASSOCIATED COLD FRONT THROUGH THE REMAINDER OF THE CWA AND
INTO EASTERN KANSAS. A FEW LINGERING THUNDERSTORMS WILL BE
POSSIBLE ACROSS CENTRAL KANSAS AS WELL AS AROUND THE I-70 CORRIDOR
IN THE EVENING WITH PRECIPITATION CHANCES COMING TO AN END
SOMETIME AFTER MIDNIGHT. NORTHWESTERLY WINDS WILL BE FELT BEHIND
THIS SYSTEM AND CONTINUE THROUGH THE MOST OF SATURDAY. SKIES LOOK
TO BECOME MOSTLY CLEAR BY SUNRISE SATURDAY AND CONTINUE THROUGH
THE DAY SATURDAY AS DRIER AIR MOVES INTO THE AREA. WINDS THEN
SHIFT TO MORE OF AN EASTERLY DIRECTION SATURDAY EVENING THROUGH
SUNDAY AS AN AREA OF LOW PRESSURE DEVELOPS AND INTENSIFIES
SOUTHWEST OF THE AREA. THIS OCCURS IN RESPONSE TO AN UPPER LEVEL
OPEN WAVE DIGGING INTO THE DESERT SOUTHWEST SATURDAY, INTENSIFYING
INTO AN UPPER LEVEL LOW OVER THE FOUR CORNER`S REGION SUNDAY.
MODELS THEN SUGGEST THAT THIS LOW WILL MOVE EASTWARD ACROSS THE
SOUTHERN PLAINS MONDAY INTO TUESDAY. HOWEVER, WITH THIS SYSTEM
BEING MORE THAN 4 DAYS OUT TIMING AND POSITION WILL MOST LIKELY
CHANGE OVER THE NEXT COUPLE OF MODEL RUNS. IF FUTURE MODEL RUNS
PREDICT THIS FEATURE TO MOVE FARTHER NORTH, THE CWA COULD SEE SOME
BENEFICIAL RAIN SUNDAY NIGHT THROUGH TUESDAY. NEVERTHELESS, HIGH
CLOUDS LOOK INCREASE IN COVERAGE SUNDAY AS THIS FEATURE MOVES
CLOSER TO THE AREA WITH MOSTLY CLOUDY SKIES EXPECTED SUNDAY NIGHT
THROUGH AT LEAST MONDAY. WINDS SHIFT TO MORE OF A NORTHERLY
DIRECTION BEHIND THIS SYSTEM THROUGH TUESDAY. UPPER LEVEL RIDGING
IS THEN EXPECTED TO BUILD INTO THE WESTERN UNITED STATES BEHIND
THIS SYSTEM WITH HIGH PRESSURE BEING THE DOMINATING FACTOR AT THE
SURFACE. THIS WILL BRING DRIER CONDITIONS TO WESTERN KANSAS FOR
THE REMAINDER OF THE WEEK.
AS FOR TEMPERATURES, LOWS FRIDAY NIGHT THROUGH MONDAY NIGHT WILL
GENERALLY BE IN THE 40S WITH THE EXCEPTION OF SOUTH CENTRAL KANSAS
FRIDAY NIGHT WHERE LOWER 50S WILL BE POSSIBLE AND WEST CENTRAL
KANSAS MONDAY NIGHT WHERE UPPER 30S COULD BE POSSIBLE. HIGHS LOOK
TO BE IN THE 70S WITH A FEW AREAS ACROSS THE KS/OK BORDER REACHING
INTO THE LOWER 80S SATURDAY THEN DECREASE INTO THE 60S SUNDAY. THE
COLDEST DAY OVER THE EXTENDED PERIOD LOOKS TO BE ON MONDAY WITH
HIGHS POSSIBLY ONLY REACHING TO AROUND 60 DEGREES. HIGHS ARE
FORECASTED TO REACH INTO THE MID 60S TUESDAY WITH 70S POSSIBLE
WEDNESDAY. LOWS TUESDAY THROUGH THURSDAY MORNING LOOK TO DIP INTO
THE 40S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 656 PM CDT THU APR 23 2015
INITIALLY, THUNDERSTORMS MAY AFFECT THE GCK AND HYS TERMINALS
TONIGHT. WE INCLUDED A TEMPO GROUP AT HAYS, BUT LEFT OUT OF GCK
BASED ON RADAR TRENDS AS OF 0620 UTC. SHOULD TRENDS CHANGE AND
CONVECTION INCREASES OUT TOWARD HAMILTON COUNTY, WE WILL NEED TO
ADD TSRA TO THE GARDEN CITY TAF SOME TIME IN THE 02-05Z TIME
FRAME. LOW STRATUS WILL DEVELOP ELSEWHERE THROUGH THE NIGHT, WITH
MINIMUM CEILING/VISIBILITY EXPECTED TO BE IN THE LIFR CATEGORY
FROM ROUGHLY 09-14Z ON AVERAGE ACROSS THE AREA. IFR/MVFR CEILINGS
AFTER 14Z FRIDAY TO LATE MORNING AT GCK AND DDC AND AROUND MIDDAY
AT HYS. LATE AFTERNOON THUNDERSTORMS COULD AFFECT HAYS, BUT WE
WILL ADDRESS THAT IN THE TAF AS TIME APPROACHES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 54 81 49 78 / 40 20 20 10
GCK 50 77 48 77 / 50 20 20 10
EHA 49 76 47 79 / 30 10 10 10
LBL 54 80 48 81 / 30 10 10 10
HYS 51 73 50 73 / 60 40 40 10
P28 56 82 52 80 / 30 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
536 PM MDT THU APR 23 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 112 PM MDT THU APR 23 2015
LOW CLOUDS THAT WERE PRESENT ACROSS THE AREA DURING THE MORNING
HOURS CONTINUED TO LINGER FOR SOME LOCATIONS ACROSS THE TRI STATE
AREA IN THE EARLY AFTERNOON ON VISIBLE SATELLITE IMAGERY...HOWEVER
MOST LOCATIONS WERE UNDER PARTLY TO MOSTLY CLEAR SKIES. RAP 500 MB
ANALYSIS AND WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH ACROSS
THE CENTRAL HIGH PLAINS REGION...HOWEVER A LONGWAVE TROUGH ACROSS
THE GREAT BASIN REGION WAS MOVING EASTWARD INTO THE CENTRAL HIGH
PLAINS.
THE ADVANCING TROUGH WILL BRING SOME POCKETS OF HIGHER POTENTIAL
VORTICITY VALUES ACROSS THE TRI STATE AREA LATER THIS AFTERNOON AND
TONIGHT...WHICH WILL HELP DESTABILIZE THE ATMOSPHERE AND CAUSE
STORMS TO DEVELOP. A SURFACE STATIONARY BOUNDARY TO THE WEST ALONG
THE COLORADO FRONT RANGE WILL ALSO PROVIDE THE NEEDED PUSH AT THE
SURFACE TO GET STORMS GOING. MOST MODEL GUIDANCE HAS INITIATION
OCCURRING SOMETIME BETWEEN 21 AND 00Z IN EASTERN COLORADO WITH
STORMS GETTING GOING BY 00Z. PROFILE CAPE BETWEEN 1000 AND 1500
J/KG AND BULK SHEAR BETWEEN 30 AND 35 KTS MAY BE ENOUGH TO CAUSE
SOME STORMS TO PRODUCE LARGE HAIL...AND DRY MID LEVELS IN MODEL
SOUNDINGS WITH DCAPE BETWEEN 800 AND 1000 J/KG COULD RESULT IN
DAMAGING WINDS GUSTS. THE SHEAR VALUES DIMINISH OVERNIGHT...BUT
CAPE WILL STILL BE PRESENT OVERNIGHT AS STORMS MOVE EASTWARD.
THEREFORE...EXPECTING STORMS TO CONTINUE OVERNIGHT FOR SOME
LOCATIONS.
THE SURFACE STATIONARY FRONTAL BOUNDARY WILL REMAIN DRAPED ACROSS
THE TRI STATE AREA OVERNIGHT...WHICH WILL BRING SOUTHEAST WINDS AT
THE SURFACE AND INCREASED RELATIVE HUMIDITIES OVERNIGHT. AS A
RESULT...FOG WILL DEVELOP AND CLOUD COVER WILL REMAIN INCREASED
OVERNIGHT. EXPECTING LOW TEMPERATURES TO BE SLIGHTLY WARMER AS A
RESULT OF THE BLANKETING CLOUD COVER IN THE UPPER 40S.
FOG AND LOWER CLOUDS WILL BEGIN TO DIMINISH TOWARD THE EARLY TO MID
MORNING HOURS...BUT CLOUDS WILL RETURN DURING THE EARLY AFTERNOON AS
A SURFACE WARM FRONT APPROACHES THE TRI STATE AREA. RAIN SHOWERS
AND THUNDERSTORMS WILL DEVELOP IN THE LATE MORNING TO EARLY
AFTERNOON HOURS...MAINLY EAST OF HIGHWAY 83. CAPE VALUES AROUND
1000 J/KG AND BULK SHEAR BETWEEN 35 AND 40 KTS WILL BRING SOME
SEVERE POTENTIAL WITH LARGE HAIL AND DAMAGING WINDS...ALTHOUGH THE
MAIN ATMOSPHERIC DYNAMICS ARE WELL EAST OF OUR FORECAST AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 241 PM MDT THU APR 23 2015
THE UPPER TROUGH AND SURFACE LOW MOVING ACROSS THE AREA ON FRIDAY
WILL CONTINUE TO LIFT ENE AS A CLOSED LOW FRIDAY NIGHT WITH WEAK
SHORT WAVE RIDGING ALOFT OVER THE CENTRAL HIGH PLAINS ON SATURDAY.
SATURDAY LOOKS MOSTLY DRY BETWEEN SYSTEMS WITH THE NEXT LOW
PRESSURE CENTER DIVING INTO THE SOUTHWEST U.S. SOUTH OF THE
4-CORNERS REGION DURING BY SUNDAY MORNING. THE LOW ALOFT MOVES
INTO THE WEST TEXAS PANHANDLE REGION BY MONDAY MORNING...MOVING
SLOWLY INTO POSITION OVER EAST TEXAS AND EAST OKLAHOMA BY TUESDAY
MORNING AS THE SURFACE LOW TRACKS FURTHER SOUTH ALONG THE GULF
COAST OF TEXAS.
WITH THE MAIN LOW PRESSURE AREA ACROSS THE SOUTH CENTRAL U.S. WELL
SOUTH OF THE FORECAST AREA...THE SATURDAY NIGHT THROUGH MONDAY
NIGHT TIME FRAME WILL REMAIN UNSETTLED ACROSS THE FORECAST AREA WITH
A CHANCE OF RAIN SHOWERS AND THUNDERSTORMS...BUT EXPECT THE BULK
OF THE PRECIPITATION TO STAY OVER THE SOUTHERN PLAINS. TUESDAY
THROUGH THURSDAY SHOULD BE DRY AS THE AMPLIFYING RIDGE OVER THE
WEST COAST MOVES OVER THE ROCKIES AND HIGH PLAINS REGION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 530 PM MDT THU APR 23 2015
KGLD...A SERIES OF UPPER LEVEL DISTURBANCES WILL MOVE ACROSS THE
AREA THIS EVENING AND FOR NOW KEPT VCTS IN THE FORECAST. AFTER
ACTIVITY MOVES AWAY FROM THE TERMINAL WE SHOULD SEE STRATUS/FG/BR
AND MAYBE SOME LIGHT DRIZZLE MOVE IN FROM THE SOUTHEAST AROUND 06Z
AND LINGER THROUGH 15Z OR SO BEFORE WEST THEN NORTHWEST WINDS
AROUND 10KTS MOVE IN PUSHING THE LOW CLOUDS EAST OF THE TERMINAL
AND ALLOWING VFR CONDITIONS TO RETURN.
KMCK...SHOULD HAVE VFR CONDITIONS THROUGH 06Z THEN QUICKLY BECOME
MVFR AROUND 07Z THEN IFR/VLIFR BY 09Z. THE VLIFR CONDITIONS WITH
FOG/BR AND MAYBE SOME DRIZZLE SHOULD CONTINUE THROUGH 16Z BEFORE
IMPROVING QUICKLY TO VFR BY 17Z OR SO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...MK
LONG TERM...LOCKHART
AVIATION...99
AREA FORECAST DISCUSSION
NWS TOPEKA KS
622 PM CDT Thu Apr 23 2015
...AVIATION UPDATE...
.SHORT TERM...(This Evening through Friday)
Issued at 329 PM CDT THU APR 23 2015
A mid-level ridge was in place over the Central and Southern Plains
today with a mid-level trough progressing eastward across the
northeastern U.S. and another trough noted just north of the Baja
Peninsula. At the surface, southeasterly winds prevailed as high
pressure remained stationed just east of the forecast area. This
southeasterly flow helped to keep a low/mid cloud deck in place
across much of the region today, limiting the daytime heating.
However, visible satellite imagery showed more breaks in the cloud
cover near the Kansas/Nebraska border, resulting in afternoon
temperatures reaching into the middle 60s. Further south in
locations with more persistent cloud cover afternoon temperatures
struggled to reach near 60 degrees.
The mid-level trough north of the Baja Peninsula will lift
northeastward toward the Four Corners region overnight and progress
north of the Texas/Oklahoma panhandles Friday afternoon, which will
help to provide ample mid-level support for thunderstorm activity
late Friday afternoon through Friday evening. Ahead of this
advancing trough, water vapor imagery this afternoon showed a few
weak embedded shortwaves developing along the lee-side of the trough
over Wyoming and Colorado with increased cloud cover noted over that
region. Models show these weak waves shifting eastward with the
eastward progression of the trough, moving into Nebraska and
northern Kansas overnight into Friday morning. In general,
short-range models have trended a bit weaker with the shower and
thunderstorm potential for late tonight through the morning hours as
the region should remain capped and forcing is limited. However,
with MUCAPE values upwards of 500-1000 J/kg and 45-55kts of 0-6km
shear, cannot rule out the potential for a few strong elevated
thunderstorms to develop in which some small hail will be possible.
Short-range models show that the precipitation should be pretty
isolated this evening and become more widely scattered through the
overnight hours before diminishing in coverage from west to east
during the mid to late morning hours. As a result, models suggest
that we could see a window of a few hours from mid/late morning
through early/mid afternoon in which locations are
precipitation-free and, according to some model soundings, may
potentially see some breaks in the cloud cover, especially closer
toward central Kansas. This diminish in cloud cover will allow for
more daytime heating in the afternoon hours to boost temperatures
into the low/mid 70s from central to east central Kansas, with
cooler temperatures in the mid/upper 60s across northeast Kansas
from the lingering cloud cover. However, these high temperatures
will be very dependent upon how quickly the morning precipitation
dissipates and whether or not we are able to diminish the cloud
cover enough during the early/mid afternoon hours, so we will need
to continue to closely monitor these short-term conditions.
.LONG TERM...(Friday Night through Thursday)
Issued at 329 PM CDT THU APR 23 2015
Friday afternoon into the overnight presents a complicated weather
scenario with a likelihood of severe weather in the area, and a
potential for a few significant severe events.
The primary forecast questions through this period will be 1) How
far north does the warm sector surge? 2) How broad east/west will
the unstable warm sector be? 3) How much and how soon will the
boundary layer stabilize by mid to late evening?
In terms of the questions above, various model guidance are
generally in the same ballpark regarding how far north the warm
sector will surge, but the northern edge of the surface based
instability ranges from somewhere near the Nebraska border (GFS) to
a Council Grove to Lawrence line (NAM/NMM). The rest of guidance is
in between, and frankly the ECMWF rendition of the surface low and
warm front track looks to be quite reasonable, with the warm sector
coming as far north as Minneapolis to Manhattan to Holton line. Most
indications are also that the warm sector will not be particularly
broad east/west, and this *may* be able to limit the potential for
long track severe storms a bit as the individual storm forward speed
(40+ mph) should be faster than the system as a whole, and they
could move toward less unstable air with time. In terms of evening
stabilization, all indications point to an unstable warm sector
airmass through approximately 8-11 PM before becoming increasingly
stable. This is not entirely for sure as the surface low will track
directly across the area after midnight, but it does seem likely
that CINH will increase and the tornado threat decrease by late
evening.
The relative certainties in this forecast are following
1) Thunderstorms will develop and move across the forecast area. 2)
Wind shear parameters are very impressive and will support storm
organization. 3) The combination of steep lapse rates and strong
shear will support large hail (some very large) in storms both north
and south of the front.
The rest of the details are fuzzier but important. Damaging wind
potential does not appear to be a huge threat given low LCL heights,
but the potential for some upscale growth by mid/late evening and
very strong ambient wind fields suggest that a wind threat could
develop. The potential for tornadoes is conditional, but very
present. A worst case scenario would be if cells can remain
semi-discrete or move east of the main cluster of convection as any
isolated supercell in the warm sector would have full access to 30+
KTS of 0-1 km wind shear underneath a strong mid level steering flow
(60 KTS at 500 hPa) and exhaust jet aloft (130 KTS at 250 hPa).
There would seem to be a primary window of opportunity between 6 PM
and 10 PM for tornado potential, especially with any isolated
supercells, as the low level jet rapidly intensifies during this
period but inhibition is slow to increase. The take away message is
that the potential exists for all modes of severe weather, and while
there are complicating factors, it will be important to prepare for
a few significant severe storms.
Precipitation looks to exit the area by sunrise on Saturday. A cold
front will then move into the area from the north on Saturday
afternoon. There will be some weak instability across the area, but
most indications point to a slightly capped boundary layer with weak
forcing along the front so currently have a dry afternoon forecast.
However, if low level moisture is a bit deeper or if temperatures
ahead of the front warm up more than forecast, could possibly see a
storm or two develop.
The remainder of the forecast is rather uneventful. Have maintained
a slight chance for showers early next week as a slow moving closed
upper low drifts across the southern Plains, but for the most part
it looks like precip should remain south of the forecast area.
Temperatures look to be near or slightly below normal for much of
the long term period.
&&
.AVIATION...(For the 00Z TAFs through 00Z Friday Evening)
Issued at 622 PM CDT THU APR 23 2015
The latest RAP and NAM forecast soundings are a little stronger
with the inversion which delays the development of elevated
showers and storms. The HRRR also supports this idea. Because
there is no obvious feature to pinpoint where storms my develop,
have opted to maintain a VCTS for the window when elevated precip
is most likely to occur. It still looks like CIGS could lower to
MVFR overnight as isentropic lift and moisture advection persists.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
324 PM MDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 225 PM MDT WED APR 22 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
NORTHERN AND SOUTHERN JET STREAMS SPLIT AROUND OUR CWA...WITH WEAK
RIDGING EXTENDING FROM THE SOUTHERN PLAINS AND ACROSS THE CENTRAL
ROCKIES. PACIFIC MOISTURE PLUME IS UNDERCUTTING UPPER RIDGE WITH
WEAK SHORTWAVE TROUGHS ROTATING NORTH AND EAST THROUGH THE
SOUTHERLY STORM TRACK. AT THE SURFACE A STATIONARY FRONT HAS
SLOWLY BEGUN THE PROCESS OF MOVING EAST WITH RADAR SHOWING
CONVECTION DEVELOPING IN THE WEAKLY UNSTABLE AIR MASS BEHIND THIS
FEATURE OVER THE HIGHER TERRAIN IN COLORADO.
THIS AFTERNOON TONIGHT...INITIAL CONCERN IS ON COVERAGE AND
PROGRESS OF THUNDERSTORM ACTIVITY IN COLORADO TOWARDS OUR CWA.
GUIDANCE SHOWS INCREASING INSTABILITY IN OUR WESTERN CWA...WHICH
COULD FAVOR THIS ACTIVITY MAKING AS FAR EAST AS THE CO/KS STATE
LINE. WHILE MOST OF THIS ACTIVITY WILL BE TIED TO DAYTIME
HEATING...WAA OVERNIGHT AND NOSE OF LLJ COULD SUPPORT
THUNDERSTORM LINGERING LATE THIS EVENING...OR SHOWERS AFTER
MIDNIGHT AS INSTABILITY WANES. MID LEVELS ARE NOT PARTICULARLY
MOIST AND DESPITE VERY GOOD OVERNIGHT MOISTURE ADVECTION WITHIN
THE BOUNDARY LAYER CAP ABOVE THIS WOULD LIKELY LIMIT CONVECTIVE
POTENTIAL FOR ANY NON ELEVATED PARCELS. I KEPT SLIGHT CHANCE OF
THUNDERSTORMS IN THE EVENING WITH SHOWERS LINGERING AFTER
MIDNIGHT THROUGH THURSDAY MORNING. CONSIDERING THE NEAR SATURATED
BOUNDARY LAYER THE PRECIP SIGNAL IN GUIDANCE MAY ACTUALLY BE
DRIZZLE/FOG.
THURSDAY...NAM SOUNDINGS INDICATE POTENTIAL FOR LINGERING
STRATUS/DRIZZLE DURING THE DAY...HOWEVER OVERALL PATTERN SHOULD
SUPPORT CLEARING SKIES FROM THE WEST WITH WARMER CONDITIONS ACROSS
EASTERN COLORADO. A STRONGER SHORTWAVE TROUGH WILL BEGIN TO MOVE
INTO THE CWA FROM THE WEST WITH INCREASING THUNDERSTORM CHANCES
ONCE AGAIN IN EASTERN COLORADO WHERE BETTER INSTABILITY IS
ADVERTISED ALONG WITH STRONGER LIFT. CONFIDENCE WAS HIGH ENOUGH
TO KEEP CHANCE POPS IN PLACE LATE THURSDAY AFTERNOON. HIGH
TEMPERATURES THURSDAY WILL BE TRICKY AND HIGHLY DEPENDENT ON
STRATUS CLEARING. HIGHS NEAR 70F (MAINLY IN THE WEST) ARE POSSIBLE
WHERE BEST CHANCE FOR CLEAR SKIES IS CURRENTLY ANTICIPATED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 232 PM MDT WED APR 22 2015
THE UPPER RIDGE AXIS EXTENDING FROM THE GULF OF MEXICO THROUGH
THE NORTHERN HIGH PLAINS FLATTENS SOMEWHAT LATE THURSDAY INTO
THURSDAY NIGHT AS A SHORT WAVE TROUGH MOVES OUT OF THE SOUTHWEST
U.S. AND OVER THE CENTRAL PLAINS THURSDAY NIGHT. THE LEE SURFACE
TROUGH ALONG THE FRONT RANGE THAT DEEPENS IN RESPONSE TO THE UPPER
SHORT WAVE TROUGH HAS GOOD SOUTHEASTERLY FLOW AHEAD OF IT THAT
WILL BRING AMPLE GULF MOISTURE INTO THE REGION. SCATTERED STRONG
THUNDERSTORMS ARE POSSIBLE ACROSS THE FORECAST AREA THURSDAY NIGHT
AS A RESULT
THE MAIN UPPER TROUGH AXIS BEGINS TO LIFT OUT ACROSS THE
4-CORNERS REGION AND INTO THE CENTRAL AND SOUTHERN HIGH PLAINS
REGION BY FRIDAY AFTERNOON...WITH THE CENTROID OF THE TROUGH
MOVING OVER E CO/NW KS. DEWPOINTS IN THE 40S ACROSS THE AREA ON
THURSDAY AND THURSDAY NIGHT WILL INCREASE INTO THE LOWER 50S
ACROSS MAINLY THE EASTERN PORTION OF THE FORECAST AREA WHILE DRYER
AIR MOVES INTO THE WEST AS THE TROUGH MOVES EAST AND FORMS A
CLOSED LOW THAT MOVES ACROSS SOUTHERN KANSAS FRIDAY EVENING. WITH
AN INSTABILITY AXIS PRESENT OVER CENTRAL KANSAS...IT IS POSSIBLE
THE FORECAST AREA COULD SEE SOME STRONG TO SEVERE THUNDERSTORMS
MAINLY ACROSS THE FAR EASTERN SECTIONS THAT WILL BECOME MORE
WIDESPREAD AND STRONGER OVERNIGHT AS THEY MOVE FURTHER TO THE
EAST.
SHORT WAVE RIDGING IS EXPECTED BETWEEN THE EXITING TROUGH AS IT
LIFTS OUT OF THE REGION AND THE NEXT UPPER TROUGH THAT STARTS TO
DEEPEN OVER THE INTERMOUNTAIN WEST BETWEEN SATURDAY AND SATURDAY
EVENING. MODEL SOLUTIONS HAVE A LOW CENTER CONSOLIDATING AND
MOVING QUICKLY ACROSS NEW MEXICO SUNDAY EVENING. THEN AS MODEL
SOLUTIONS BEGIN TO DIVERGE TO A GREATER DEGREE...THE LOW SLOWS AND
ENDS UP SOMEWHERE OVER E OKLAHOMA/E TEXAS BY TUESDAY MORNING AS A
BLOCKING HIGH AMPLIFIES OVER THE WESTERN UNITED SATES. THAT RIDGE
MOVES OVER THE ROCKIES AND HIGH PLAINS REGION BY WEDNESDAY
EVENING. THE WEEKEND AND FIRST PART OF NEXT WEEK WILL REMAIN
UNSETTLED WITH SCATTERED THUNDERSTORMS POSSIBLE ACROSS THE AREA AS
THE LOW MOVES ACROSS THE SOUTHERN PLAINS. DRYER AND WARMER
CONDITIONS ARE ANTICIPATED BY MID-WEEK AS SURFACE HIGH PRESSURE
AND THE RIDGE ALOFT MOVE OVER THE HIGH PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1121 AM MDT WED APR 22 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE FIRST 12 HOURS OF THE TAF
PERIOD AT BOTH KGLD AND KMCK WITH PRIMARY AVIATION CONCERN BEING
POTENTIAL FOR ISOLATED THUNDERSTORMS OR SHOWERS. WHILE KGLD HAS
THE BEST CHANCE FOR THUNDERSTORM ACTIVITY TO SPREAD EAST OUT OF
COLORADO...CONFIDENCE IN COVERAGE IS STILL TOO LOW FOR TAF
INCLUSION AT THIS TIME.
INCREASING LOW LEVEL MOISTURE ALONG STALLED FRONTAL BOUNDARY LATE
TONIGHT WILL SUPPORT STRATUS AND POSSIBLY LIGHT FOG DEVELOPMENT BY
09Z AT KGLD...TRANSITIONING EAST THROUGH THURSDAY MORNING. WITH
GUIDANCE SHOWING BETTER CONSISTENCY I ADDED IFR CIG GROUP TO KGLD
TAF AFTER 09Z AND KEPT MENTION OF MVFR CIGS AT KMCK AFTER 15Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
225 PM MDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 225 PM MDT WED APR 22 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
NORTHERN AND SOUTHERN JET STREAMS SPLIT AROUND OUR CWA...WITH WEAK
RIDGING EXTENDING FROM THE SOUTHERN PLAINS AND ACROSS THE CENTRAL
ROCKIES. PACIFIC MOISTURE PLUME IS UNDERCUTTING UPPER RIDGE WITH
WEAK SHORTWAVE TROUGHS ROTATING NORTH AND EAST THROUGH THE
SOUTHERLY STORM TRACK. AT THE SURFACE A STATIONARY FRONT HAS
SLOWLY BEGUN THE PROCESS OF MOVING EAST WITH RADAR SHOWING
CONVECTION DEVELOPING IN THE WEAKLY UNSTABLE AIR MASS BEHIND THIS
FEATURE OVER THE HIGHER TERRAIN IN COLORADO.
THIS AFTERNOON TONIGHT...INITIAL CONCERN IS ON COVERAGE AND
PROGRESS OF THUNDERSTORM ACTIVITY IN COLORADO TOWARDS OUR CWA.
GUIDANCE SHOWS INCREASING INSTABILITY IN OUR WESTERN CWA...WHICH
COULD FAVOR THIS ACTIVITY MAKING AS FAR EAST AS THE CO/KS STATE
LINE. WHILE MOST OF THIS ACTIVITY WILL BE TIED TO DAYTIME
HEATING...WAA OVERNIGHT AND NOSE OF LLJ COULD SUPPORT
THUNDERSTORM LINGERING LATE THIS EVENING...OR SHOWERS AFTER
MIDNIGHT AS INSTABILITY WANES. MID LEVELS ARE NOT PARTICULARLY
MOIST AND DESPITE VERY GOOD OVERNIGHT MOISTURE ADVECTION WITHIN
THE BOUNDARY LAYER CAP ABOVE THIS WOULD LIKELY LIMIT CONVECTIVE
POTENTIAL FOR ANY NON ELEVATED PARCELS. I KEPT SLIGHT CHANCE OF
THUNDERSTORMS IN THE EVENING WITH SHOWERS LINGERING AFTER
MIDNIGHT THROUGH THURSDAY MORNING. CONSIDERING THE NEAR SATURATED
BOUNDARY LAYER THE PRECIP SIGNAL IN GUIDANCE MAY ACTUALLY BE
DRIZZLE/FOG.
THURSDAY...NAM SOUNDINGS INDICATE POTENTIAL FOR LINGERING
STRATUS/DRIZZLE DURING THE DAY...HOWEVER OVERALL PATTERN SHOULD
SUPPORT CLEARING SKIES FROM THE WEST WITH WARMER CONDITIONS ACROSS
EASTERN COLORADO. A STRONGER SHORTWAVE TROUGH WILL BEGIN TO MOVE
INTO THE CWA FROM THE WEST WITH INCREASING THUNDERSTORM CHANCES
ONCE AGAIN IN EASTERN COLORADO WHERE BETTER INSTABILITY IS
ADVERTISED ALONG WITH STRONGER LIFT. CONFIDENCE WAS HIGH ENOUGH
TO KEEP CHANCE POPS IN PLACE LATE THURSDAY AFTERNOON. HIGH
TEMPERATURES THURSDAY WILL BE TRICKY AND HIGHLY DEPENDENT ON
STRATUS CLEARING. HIGHS NEAR 70F (MAINLY IN THE WEST) ARE POSSIBLE
WHERE BEST CHANCE FOR CLEAR SKIES IS CURRENTLY ANTICIPATED.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 243 AM MDT WED APR 22 2015
PRECIP WILL MOVE OUT OF THE AREA SATURDAY MORNING BEFORE A TROUGH
ENTERS THE AREA LATE SATURDAY/EARLY SUNDAY. THIS WILL PRODUCE
ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND
SUNDAY. MODELS HAVE TRENDED STRONGER WITH THIS SYSTEM...INCREASING
PRECIPITATION PROBABILITY. PRECIP CHANCE CONTINUES INTO MONDAY AS
AN UPPER LEVEL LOW CLOSES OFF AND MOVES EAST.
TEMPERATURES LOOK TO BE RELATIVELY CONSISTENT AND IN THE 60S
THROUGH MONDAY. A RIDGE WILL BEGIN TO MOVE INTO THE AREA ON
TUESDAY BRINGING DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1121 AM MDT WED APR 22 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE FIRST 12 HOURS OF THE TAF
PERIOD AT BOTH KGLD AND KMCK WITH PRIMARY AVIATION CONCERN BEING
POTENTIAL FOR ISOLATED THUNDERSTORMS OR SHOWERS. WHILE KGLD HAS
THE BEST CHANCE FOR THUNDERSTORM ACTIVITY TO SPREAD EAST OUT OF
COLORADO...CONFIDENCE IN COVERAGE IS STILL TOO LOW FOR TAF
INCLUSION AT THIS TIME.
INCREASING LOW LEVEL MOISTURE ALONG STALLED FRONTAL BOUNDARY LATE
TONIGHT WILL SUPPORT STRATUS AND POSSIBLY LIGHT FOG DEVELOPMENT BY
09Z AT KGLD...TRANSITIONING EAST THROUGH THURSDAY MORNING. WITH
GUIDANCE SHOWING BETTER CONSISTENCY I ADDED IFR CIG GROUP TO KGLD
TAF AFTER 09Z AND KEPT MENTION OF MVFR CIGS AT KMCK AFTER 15Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1239 AM CDT WED APR 22 2015
.UPDATE...
ISSUED AT 1238 AM CDT WED APR 22 2015
UPDATED AVIATION SECTION FOR 06Z TAFS.
UPDATE
FOR AVIATION SECTION ONLY.
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 215 PM CDT TUE APR 21 2015
NEAR TERM ON TRACK...AS CONVECTION CONTINUES TO TAKE SHAPE OVER
SOUTHERN INTO SOUTHEAST MISSOURI...LIGHTNING NOW OBSERVED WEST OF
OUR CWFA. WILL CONTINUE TO MONITOR FOR THE POSSIBILITY OF SOME
HAIL AND GUSTY WINDS GIVEN THE STEEP LAPSE RATES AND LOW FREEZING
LEVELS...DESPITE LACK OF LOW LEVEL MOISTURE. THE CHANCES WILL
CONTINUE THROUGH THE OVERNIGHT AS A BOUNDARY SETTLES SOUTH ACROSS
THE REGION. WILL DIMINISH POPS FROM NW TO SE WEDNESDAY MORNING...DRY
BY AFTERNOON. WILL KEEP IT DRY WEDNESDAY NIGHT THROUGH THURSDAY
WITH WEAK HIGH PRESSURE ANGLING IN FROM THE UPPER MIDWEST. CHANCES
OF SHOWERS MAY EXIST JUST SOUTH OF THE AREA NEAR OUR CWFA BORDER.
CAN ADJUST IF NEED BE. TEMPS A BLEND OF MOS AND EXISTING NUMBERS.
NAM HIGH RES AND HRRR A REASONABLE APPROACH FOR CONVECTIVE TRENDS
THROUGH 06Z.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 215 PM CDT TUE APR 21 2015
THE OPERATIONAL MODELS ARE TRYING TO FALL SOMEWHAT IN LINE WITH
PRIOR ENSEMBLE MEAN SOLUTIONS THROUGH SUNDAY. ALL IN ALL...
CONFIDENCE CONTINUES TO INCREASE FOR THE FIRST SYSTEM FRIDAY
THROUGH SATURDAY. UPPER TROF SHOULD EJECT NE INTO THE PLAINS BY
00Z SAT WITH MOISTURE QUICKLY SPREADING EAST BY FRIDAY AFTERNOON
AND EVENING. S/WV RIDGE AHEAD OF THE TROF NOT STRONG ENOUGH TO
WARD OFF ONCOMING SHRA/TSRA CHANCE. SO WE ARE ON THE AGGRESSIVE
SIDE OF THE ENVELOPE. LIKELY POPS STILL IN PLAY FOR FRIDAY NIGHT
WITH CHANCE TO LOW END LIKELY SATURDAY AS WELL...AS THE UPPER TROF
WEAKENS...AND THE REMNANT ENERGY TURNS ESE ACROSS THE AREA
SATURDAY...CONTINUING THE CHANCE OF CONVECTION. SURFACE BOUNDARY
SHOULD STAY JUST TO OUR SOUTH...SO ESSENTIALLY ELEVATED CONVECTION.
CHANCES TAIL OFF SATURDAY NIGHT WITH A DRY FORECAST IN PLACE FOR
SUNDAY. FOR MONDAY THROUGH TUESDAY...THE ENSEMBLE MEAN SOLUTIONS
WERE UTILIZED AND OPERATIONAL MODELS THROWN OUT. A HIGHLY COMPLEX
PATTERN IS FORECAST TO EVOLVE WITH SOME KIND OF A TROUGH EAST OF
THE PLAINS AND RIDGE WEST. HOWEVER THERE IS TOO MUCH VARIABILITY
IN THE DETAILS TO SIDE WITH ANY OPS SOLUTION AT THIS POINT. ITS
GOING TO CHANGE. WE FEE COMFORTABLE MAINTAINING LOW CHANCE POPS
FOR SHOWERS GIVEN THE UNSETTLED LOOK TO THE PATTERN. TEMPS WERE A
BLEND OF BASE MODEL OUTPUT AND EXISTING FORECAST NUMBERS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 215 PM CDT TUE APR 21 2015
NEAR TERM ON TRACK...AS CONVECTION CONTINUES TO TAKE SHAPE OVER
SOUTHERN INTO SOUTHEAST MISSOURI...LIGHTNING NOW OBSERVED WEST OF
OUR CWFA. WILL CONTINUE TO MONITOR FOR THE POSSIBILITY OF SOME
HAIL AND GUSTY WINDS GIVEN THE STEEP LAPSE RATES AND LOW FREEZING
LEVELS...DESPITE LACK OF LOW LEVEL MOISTURE. THE CHANCES WILL
CONTINUE THROUGH THE OVERNIGHT AS A BOUNDARY SETTLES SOUTH ACROSS
THE REGION. WILL DIMINISH POPS FROM NW TO SE WEDNESDAY MORNING...DRY
BY AFTERNOON. WILL KEEP IT DRY WEDNESDAY NIGHT THROUGH THURSDAY
WITH WEAK HIGH PRESSURE ANGLING IN FROM THE UPPER MIDWEST. CHANCES
OF SHOWERS MAY EXIST JUST SOUTH OF THE AREA NEAR OUR CWFA BORDER.
CAN ADJUST IF NEED BE. TEMPS A BLEND OF MOS AND EXISTING NUMBERS.
NAM HIGH RES AND HRRR A REASONABLE APPROACH FOR CONVECTIVE TRENDS
THROUGH 06Z.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 215 PM CDT TUE APR 21 2015
THE OPERATIONAL MODELS ARE TRYING TO FALL SOMEWHAT IN LINE WITH
PRIOR ENSEMBLE MEAN SOLUTIONS THROUGH SUNDAY. ALL IN ALL...
CONFIDENCE CONTINUES TO INCREASE FOR THE FIRST SYSTEM FRIDAY
THROUGH SATURDAY. UPPER TROF SHOULD EJECT NE INTO THE PLAINS BY
00Z SAT WITH MOISTURE QUICKLY SPREADING EAST BY FRIDAY AFTERNOON
AND EVENING. S/WV RIDGE AHEAD OF THE TROF NOT STRONG ENOUGH TO
WARD OFF ONCOMING SHRA/TSRA CHANCE. SO WE ARE ON THE AGGRESSIVE
SIDE OF THE ENVELOPE. LIKELY POPS STILL IN PLAY FOR FRIDAY NIGHT
WITH CHANCE TO LOW END LIKELY SATURDAY AS WELL...AS THE UPPER TROF
WEAKENS...AND THE REMNANT ENERGY TURNS ESE ACROSS THE AREA
SATURDAY...CONTINUING THE CHANCE OF CONVECTION. SURFACE BOUNDARY
SHOULD STAY JUST TO OUR SOUTH...SO ESSENTIALLY ELEVATED CONVECTION.
CHANCES TAIL OFF SATURDAY NIGHT WITH A DRY FORECAST IN PLACE FOR
SUNDAY. FOR MONDAY THROUGH TUESDAY...THE ENSEMBLE MEAN SOLUTIONS
WERE UTILIZED AND OPERATIONAL MODELS THROWN OUT. A HIGHLY COMPLEX
PATTERN IS FORECAST TO EVOLVE WITH SOME KIND OF A TROUGH EAST OF
THE PLAINS AND RIDGE WEST. HOWEVER THERE IS TOO MUCH VARIABILITY
IN THE DETAILS TO SIDE WITH ANY OPS SOLUTION AT THIS POINT. ITS
GOING TO CHANGE. WE FEE COMFORTABLE MAINTAINING LOW CHANCE POPS
FOR SHOWERS GIVEN THE UNSETTLED LOOK TO THE PATTERN. TEMPS WERE A
BLEND OF BASE MODEL OUTPUT AND EXISTING FORECAST NUMBERS.
&&
.AVIATION...
ISSUED AT 1238 AM CDT WED APR 22 2015
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. COLD
FRONT ADVANCING IN FROM THE NORTH WILL LEAD TO VCSH AT ALL
TERMINALS TONIGHT WITH WINDS SHIFTING AROUND TO THE NORTHWEST BY
TMRW MORNING. COULD HAVE SOME GUSTS UP TO 20 KTS DURING THE DAY AT
EVV/OWB. HIGH PRESSURE WILL BUILD IN BY TMRW EVENING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...SP
AVIATION...SP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
141 PM CDT WED APR 22 2015
.AVIATION...
CLUSTER OF TSTMS CURRENTLY OVER SW AR IS EXPECTED TO MOVE EWD OVER
THE NEXT FEW HOURS...BUT SHOULD NOT IMPACT ANY TERMINALS ASIDE
FROM KTXK. LATER TONIGHT...TSTMS ARE EXPECTED TO DEVELOP ACROSS
THE RED RIVER AND MOVE SEWD INTO OUR REGION. THERE IS QUITE A BIT
OF UNCERTAINTY AS TO THE TIMING AND LOCATION OF THESE STORMS...SO
WILL KEEP MENTION OF TSTMS OUT OF THE TAFS ASIDE FROM THE USE OF
VCTS. OTHERWISE...WITH INCREASING LL MOISTURE TO CONTINUE...
STRATUS DEVELOPMENT IS EXPECTED FOR MOST SITES AFTER AROUND
09Z...WITH SOME IMPROVEMENT POSSIBLE AFTER SUNRISE. /12/
&&
.PREV DISCUSSION... /ISSUED 1038 AM CDT WED APR 22 2015/
DISCUSSION...
WEAKENING MCS MOVG INTO RED RIVER VALLEY. GOOD DAYTIME HEATING
WILL CONTINUE AHEAD OF THE DECAYING SYSTEM OUTFLOW THAT WILL PUSH
EASTWARD INTO SW AR/NW TX AND NW LA THIS AFTN. BETWEEN AIRMASS
RECOVERY ACROSS NORTHERN AREAS NEAR THIS MCS...AND MARGINAL
MOISTURE IN UNSTABLE AIRMASS ACROSS REST OF AREA...EXPECT STG
CONVECTIVE REDEVELOPMENT TO OCCUR LATE AFTN/EARLY EVE.
THUS...LOWERED POPS SLIGHTLY TO 20 AND 30 PERCENT FOR MOST OF
NORTHERN LA...AND PORTIONS OF NE TX ALONG AND SOUTH OF I-20.
ALSO RAISED TEMPS SLIGHTLY TO LOWER/MID 80S ACROSS ROUGHLY THESE
SAME AREAS WHERE POPS HAVE BEEN LOWERED./VII/.
PREV DISCUSSION... /ISSUED 538 AM CDT WED APR 22 2015/
DISCUSSION...
AIR MASS MODIFICATION IS UNDERWAY THIS MORNING...WITH AN EXTENSIVE
BAND OF 5-6KFT CIGS HAVING DEVELOPED/SPREAD ENE ALONG AND S OF THE
I-20 CORRIDOR OF N LA/E TX. LOW LEVEL WARM/MOISTURE ADVECTION WILL
CONTINUE TODAY...AS A SLY LOW LEVEL FLOW INCREASES...AHEAD OF SFC
LOW PRESSURE THAT WILL DEEPEN BY AFTERNOON ALONG THE DRY LINE OVER
NW TX. THIS WILL DRIVE A WARM FRONT NWD TO NEAR THE RED RIVER OF N
TX ESE ACROSS NE TX AND TO NEAR THE AR/LA LINE BY AFTERNOON.
MEANWHILE...A WEAK COLD FRONT WILL DRIFT S TODAY BEFORE
TEMPORARILY BECOMING STATIONARY FROM SRN OK INTO CNTRL AR. THE
MORNING WATER VAPOR IMAGERY REVEALS A SHORTWAVE ROUNDING THE
BACKSIDE OF A LARGE UPPER CLOSED LOW/ATTENDANT LONGWAVE TROUGH
EXTENDING FROM THE NRN GREAT LAKES SW THROUGH THE MIDWEST INTO THE
OK/TX PANHANDLE. THIS SHORTWAVE HAS BEEN DRIVING AN INCREASE IN
ELEVATED CONVECTION ALONG THE FRONT OVER WRN OK...WHICH SHOULD
CONTINUE TO SPREAD SSE ALONG THE FRONTAL ZONE THIS MORNING.
ADDITIONAL REDEVELOPMENT SHOULD OCCUR LATER TODAY AS CONVERGENCE
INCREASES ALONG THE TRIPLE POINT NEAR THE RED RIVER...AND LARGE
SCALE FORCING INCREASES ALONG A SECONDARY SHORTWAVE ON THE WATER
VAPOR IMAGERY OVER SRN NM THAT WILL LIFT NE INTO THE TX PANHANDLE
ATOP THE FLAT SRN PLAINS RIDGE AND ACROSS THE RED RIVER VALLEY.
THE AIR MASS ACROSS THE WARM SECTOR IS EXPECTED TO BECOME
MODERATELY UNSTABLE THIS AFTERNOON...CHARACTERIZED BY MLCAPES OF
1500-2500 J/KG AND STEEP LAPSE RATES. IT REMAINS TO BE SEEN THOUGH
WHETHER THE CURRENT WRN OK CONVECTION MAY HELP INITIATE CONVECTION
EARLIER OVER THE RED RIVER VALLEY...BEFORE MAX DESTABILIZATION
OCCURS...THUS TAPERING THE POTENTIAL INSTABILITY. THE 00Z PROGS
ARE NOT IN GOOD AGREEMENT AT ALL IN REGARDS TO CONVECTION
PLACEMENT/TIMING...ALTHOUGH THE NEW 06Z NAM HAS TRENDED CLOSER TO
THE GFS SOLUTION WITH CONVECTION INCREASING ALONG THE WARM FRONT
OVER NE TX DURING PEAK HEATING. MEANWHILE...THE HRRR IS SUGGESTING
LITTLE IF ANY DEVELOPMENT THIS AFTERNOON NEAR THE TRIPLE
POINT...WITH MORE WIDESPREAD CONVECTION DEVELOPING E OF I-35
ACROSS ECNTRL TX BY MID TO LATE AFTERNOON. NEEDLESS TO
SAY...CONFIDENCE IS LOWER TODAY THAN TUESDAY IN REGARDS TO
CONVECTION INITIATION AND PLACEMENT.
DID MAINTAIN HIGH CHANCE POPS WITH SVR WORDING THIS AFTERNOON NW
OF THE I-30 CORRIDOR ALONG/JUST N OF THE WARM FRONT...TAPERING
CHANCE POPS DOWN A TAD FARTHER E WHERE FRONTAL CONVERGENCE IS A
BIT WEAKER AND THIS REGION IS FARTHER REMOVED FROM THE TWO LOBES
OF SHORTWAVE ENERGY TO OUR N AND W. AN MCS MAY DEVELOP THIS
EVENING ALONG THE RED RIVER VALLEY AND SHIFT ESE ALONG THE FRONT
TONIGHT /PER THE CONSISTENT GFS SOLUTION AND TO SOME EXTENT THE
ECMWF/...WITH THE THREAT OF DAMAGING WINDS/LARGE HAIL POSSIBLE.
DID CONTINUE MENTION OF SVR OVERNIGHT AREAWIDE GIVEN THE
UNCERTAINTY...ALTHOUGH THIS THREAT SHOULD DIMINISH LATE WITH THE
STABILIZING BNDRY LYR. THE SHORT TERM PROGS ALSO SUGGEST A
SLIGHTLY FASTER MOVEMENT OF THE COLD FRONT AS IT BEGINS TO
BACKDOOR SW INTO SE OK/SW AR OVERNIGHT...BEFORE PULLING UP
STATIONARY OVER N LA/E TX THURSDAY. WEAK ISENTROPIC ASCENT ATOP
THE BNDRY MAY RESULT IN SCT CONVECTION DURING THE DAY...ALTHOUGH
THE LACK OF UPPER LEVEL ENERGY SHOULD KEEP QPF AMOUNTS LIGHT. IN
ADDITION...MESOSCALE BNDRYS FROM CONVECTION THIS AFTERNOON AND
TONIGHT MAY PLAY A ROLE IN CONVECTION INITIATION THURSDAY ACROSS
THE WARM SECTOR S OF THE FRONT. BUT ATTM...CONFIDENCE IS LOW IN
REGARDS TO THE PLACEMENT OF THE SVR THREAT...THUS HAVE REMOVED SVR
MENTION FROM THE FORECAST THURSDAY...ALTHOUGH CAN/T RULE OUT AN
ISOLATED SVR STORM WITHIN THE MODERATELY UNSTABLE AIR MASS.
WILL BE WATCHING THE CLOSED SRN CA UPPER LOW AS IT EJECTS NE
ACROSS THE FOUR CORNERS REGION AND OPENS UP THURSDAY
NIGHT...ENTERING THE SRN PLAINS FRIDAY. THE WILL SET UP A STRONG
SW FLOW ALOFT...WITH A 70-80KT MID LEVEL SPEED MAX EJECTING OVER
THE SRN PLAINS FRIDAY AFTERNOON. THIS WILL RESULT IN AN INCREASING
SSWLY LOW LEVEL FLOW THURSDAY NIGHT/FRIDAY MORNING...THUS LIFTING
THE STATIONARY FRONT BACK N AS A WARM FRONT ACROSS OK/AR FRIDAY
AND HENCE BROADENING THE WARM SECTOR. THE W TX DRYLINE WILL MIX E
INTO ERN OK TO JUST W OF THE I-35 CORRIDOR OF CNTRL TX FRIDAY
EVENING...WITH BROAD DIFFLUENCE ALOFT CONTRIBUTING TO SCT TO
NUMEROUS CONVECTION AREAWIDE ESPECIALLY DURING PEAK HEATING. LOW
LEVEL WINDS DO VEER MORE ACROSS THE REGION WELL E OF THE DRYLINE
FRIDAY...WITH A MORE UNIDIRECTIONAL FLOW NOTED ABOVE 850MB. GIVEN
THE STRONG DEEP LYR SHEAR AND MODERATE MLCAPES EXPECTED TO BE IN
PLACE...A MORE PRONOUNCED SVR THREAT WILL BE POSSIBLE WITH
DAMAGING WINDS/ISOLATED TORNADOES. MID LEVEL DRY AIR SHOULD ADVECT
ENE AHEAD OF THE EJECTING TROUGH FRIDAY EVENING...THUS TAPERING
THE CONVECTION FROM W TO E OVERNIGHT...WITH THE DRYLINE PULLING UP
STATIONARY JUST W OF THE REGION. THIS BNDRY SHOULD MIX E ACROSS
THE REGION SATURDAY AS WLY WINDS INCREASE BENEATH THE MIDWEST SFC
CYCLONE...RESULTING IN PERHAPS THE WARMEST TEMPS SO FAR THIS
SPRING SEASON AS READING CLIMB WELL INTO THE MID 80S AND POSSIBLY
90 DEGREES OVER PORTIONS OF E TX/N LA.
UPPER RIDGING SHOULD AMPLIFY OVER THE CNTRL CONUS BY SUNDAY BEFORE
THE NEXT CLOSED LOW DIGS SE INTO THE SRN ROCKIES SUNDAY BEFORE
MOVING INTO THE SRN PLAINS MONDAY. THIS COULD RESULT IN ANOTHER
SVR THREAT FOR THE REGION BY THE MONDAY/TUESDAY
TIMEFRAME...ALTHOUGH DISCREPANCIES IN TIMING AMONGST THE FASTER
GFS/SLOWER ECMWF PRECLUDES A HIGHER CONFIDENCE ATTM. HOWEVER...THE
PROGS DO CONVERGE ON A PATTERN CHANGE BY MID AND LATE WEEK...WITH COOLER
AND DRIER CONDITIONS SPILLING S ACROSS THE ERN TWO-THIRDS OF THE
CONUS.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 82 64 77 67 / 30 70 40 30
MLU 83 63 77 64 / 20 70 40 20
DEQ 76 58 67 58 / 50 70 40 40
TXK 77 60 71 62 / 40 70 40 30
ELD 80 60 71 60 / 30 70 40 30
TYR 79 65 81 69 / 40 60 30 40
GGG 80 65 80 69 / 30 60 30 40
LFK 84 68 85 71 / 30 50 30 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1038 AM CDT WED APR 22 2015
.DISCUSSION...
WEAKENING MCS MOVG INTO RED RIVER VALLEY. GOOD DAYTIME HEATING
WILL CONTINUE AHEAD OF THE DECAYING SYSTEM OUTFLOW THAT WILL PUSH
EASTWARD INTO SW AR/NW TX AND NW LA THIS AFTN. BETWEEN AIRMASS
RECOVERY ACROSS NORTHERN AREAS NEAR THIS MCS...AND MARGINAL
MOISTURE IN UNSTABLE AIRMASS ACROSS REST OF AREA...EXPECT STG
CONVECTIVE REDEVELOPMENT TO OCCUR LATE AFTN/EARLY EVE.
THUS...LOWERED POPS SLIGHTLY TO 20 AND 30 PERCENT FOR MOST OF
NORTHERN LA...AND PORTIONS OF NE TX ALONG AND SOUTH OF I-20.
ALSO RAISED TEMPS SLIGHTLY TO LOWER/MID 80S ACROSS ROUGHLY THESE
SAME AREAS WHERE POPS HAVE BEEN LOWERED./VII/.
&&
.PREV DISCUSSION... /ISSUED 538 AM CDT WED APR 22 2015/
DISCUSSION...
AIR MASS MODIFICATION IS UNDERWAY THIS MORNING...WITH AN EXTENSIVE
BAND OF 5-6KFT CIGS HAVING DEVELOPED/SPREAD ENE ALONG AND S OF THE
I-20 CORRIDOR OF N LA/E TX. LOW LEVEL WARM/MOISTURE ADVECTION WILL
CONTINUE TODAY...AS A SRLY LOW LEVEL FLOW INCREASES...AHEAD OF
SFC LOW PRESSURE THAT WILL DEEPEN BY AFTERNOON ALONG THE DRY LINE
OVER NW TX. THIS WILL DRIVE A WARM FRONT NWD TO NEAR THE RED RIVER
OF N TX ESE ACROSS NE TX AND TO NEAR THE AR/LA LINE BY AFTERNOON.
MEANWHILE...A WEAK COLD FRONT WILL DRIFT S TODAY BEFORE
TEMPORARILY BECOMING STATIONARY FROM SRN OK INTO CNTRL AR. THE
MORNING WATER VAPOR IMAGERY REVEALS A SHORTWAVE ROUNDING THE
BACKSIDE OF A LARGE UPPER CLOSED LOW/ATTENDENT LONGWAVE TROUGH
EXTENDING FROM THE NRN GREAT LAKES SW THROUGH THE MIDWEST INTO THE
OK/TX PANHANDLE. THIS SHORTWAVE HAS BEEN DRIVING AN INCREASE IN
ELEVATED CONVECTION ALONG THE FRONT OVER WRN OK...WHICH SHOULD
CONTINUE TO SPREAD SSE ALONG THE FRONTAL ZONE THIS MORNING.
ADDITIONAL REDEVELOPMENT SHOULD OCCUR LATER TODAY AS CONVERGENCE
INCREASES ALONG THE TRIPLE POINT NEAR THE RED RIVER...AND LARGE
SCALE FORCING INCREASES ALONG A SECONDARY SHORTWAVE ON THE WATER
VAPOR IMAGERY OVER SRN NM THAT WILL LIFT NE INTO THE TX PANHANDLE
ATOP THE FLAT SRN PLAINS RIDGE AND ACROSS THE RED RIVER VALLEY.
THE AIR MASS ACROSS THE WARM SECTOR IS EXPECTED TO BECOME
MODERATELY UNSTABLE THIS AFTERNOON...CHARACTERIZED BY MLCAPES OF
1500-2500 J/KG AND STEEP LAPSE RATES. IT REMAINS TO BE SEEN THOUGH
WHETHER THE CURRENT WRN OK CONVECTION MAY HELP INITIATE CONVECTION
EARLIER OVER THE RED RIVER VALLEY...BEFORE MAX DESTABILIZATION
OCCURS...THUS TAPERING THE POTENTIAL INSTABILITY. THE 00Z PROGS
ARE NOT IN GOOD AGREEMENT AT ALL IN REGARDS TO CONVECTION
PLACEMENT/TIMING...ALTHOUGH THE NEW 06Z NAM HAS TRENDED CLOSER TO
THE GFS SOLUTION WITH CONVECTION INCREASING ALONG THE WARM FRONT
OVER NE TX DURING PEAK HEATING. MEANWHILE...THE HRRR IS SUGGESTING
LITTLE IF ANY DEVELOPMENT THIS AFTERNOON NEAR THE TRIPLE
POINT...WITH MORE WIDESPREAD CONVECTION DEVELOPING E OF I-35
ACROSS ECNTRL TX BY MID TO LATE AFTERNOON. NEEDLESS TO
SAY...CONFIDENCE IS LOWER TODAY THAN TUESDAY IN REGARDS TO
CONVECTION INITIATION AND PLACEMENT.
DID MAINTAIN HIGH CHANCE POPS WITH SVR WORDING THIS AFTERNOON NW
OF THE I-30 CORRIDOR ALONG/JUST N OF THE WARM FRONT...TAPERING
CHANCE POPS DOWN A TAD FARTHER E WHERE FRONTAL CONVERGENCE IS A
BIT WEAKER AND THIS REGION IS FARTHER REMOVED FROM THE TWO LOBES
OF SHORTWAVE ENERGY TO OUR N AND W. AN MCS MAY DEVELOP THIS
EVENING ALONG THE RED RIVER VALLEY AND SHIFT ESE ALONG THE FRONT
TONIGHT /PER THE CONSISTENT GFS SOLUTION AND TO SOME EXTENT THE
ECMWF/...WITH THE THREAT OF DAMAGING WINDS/LARGE HAIL POSSIBLE.
DID CONTINUE MENTION OF SVR OVERNIGHT AREAWIDE GIVEN THE
UNCERTAINTY...ALTHOUGH THIS THREAT SHOULD DIMINISH LATE WITH THE
STABILIZING BNDRY LYR. THE SHORT TERM PROGS ALSO SUGGEST A
SLIGHTLY FASTER MOVEMENT OF THE COLD FRONT AS IT BEGINS TO
BACKDOOR SW INTO SE OK/SW AR OVERNIGHT...BEFORE PULLING UP
STATIONARY OVER N LA/E TX THURSDAY. WEAK ISENTROPIC ASCENT ATOP
THE BNDRY MAY RESULT IN SCT CONVECTION DURING THE DAY...ALTHOUGH
THE LACK OF UPPER LEVEL ENERGY SHOULD KEEP QPF AMOUNTS LIGHT. IN
ADDITION...MESOSCALE BNDRYS FROM CONVECTION THIS AFTERNOON AND
TONIGHT MAY PLAY A ROLE IN CONVECTION INITIATION THURSDAY ACROSS
THE WARM SECTOR S OF THE FRONT. BUT ATTM...CONFIDENCE IS LOW IN
REGARDS TO THE PLACEMENT OF THE SVR THREAT...THUS HAVE REMOVED SVR
MENTION FROM THE FORECAST THURSDAY...ALTHOUGH CAN/T RULE OUT AN
ISOLATED SVR STORM WITHIN THE MODERATELY UNSTABLE AIR MASS.
WILL BE WATCHING THE CLOSED SRN CA UPPER LOW AS IT EJECTS NE
ACROSS THE FOUR CORNERS REGION AND OPENS UP THURSDAY
NIGHT...ENTERING THE SRN PLAINS FRIDAY. THE WILL SET UP A STRONG
SW FLOW ALOFT...WITH A 70-80KT MID LEVEL SPEED MAX EJECTING OVER
THE SRN PLAINS FRIDAY AFTERNOON. THIS WILL RESULT IN AN INCREASING
SSWRLY LOW LEVEL FLOW THURSDAY NIGHT/FRIDAY MORNING...THUS LIFTING
THE STATIONARY FRONT BACK N AS A WARM FRONT ACROSS OK/AR FRIDAY
AND HENCE BROADING THE WARM SECTOR. THE W TX DRYLINE WILL MIX E
INTO ERN OK TO JUST W OF THE I-35 CORRIDOR OF CNTRL TX FRIDAY
EVENING...WITH BROAD DIFFLUENCE ALOFT CONTRIBUTING TO SCT TO
NUMEROUS CONVECTION AREAWIDE ESPECIALLY DURING PEAK HEATING. LOW
LEVEL WINDS DO VEER MORE ACROSS THE REGION WELL E OF THE DRYLINE
FRIDAY...WITH A MORE UNIDIRECTIONAL FLOW NOTED ABOVE 850MB. GIVEN
THE STRONG DEEP LYR SHEAR AND MODERATE MLCAPES EXPECTED TO BE IN
PLACE...A MORE PRONOUNCED SVR THREAT WILL BE POSSIBLE WITH
DAMAGING WINDS/ISOLATED TORNADOES. MID LEVEL DRY AIR SHOULD ADVECT
ENE AHEAD OF THE EJECTING TROUGH FRIDAY EVENING...THUS TAPERING
THE CONVECTION FROM W TO E OVERNIGHT...WITH THE DRYLINE PULLING UP
STATIONARY JUST W OF THE REGION. THIS BNDRY SHOULD MIX E ACROSS
THE REGION SATURDAY AS WRLY WINDS INCREASE BENEATH THE MIDWEST SFC
CYCLONE...RESULTING IN PERHAPS THE WARMEST TEMPS SO FAR THIS
SRPING SEASON AS READING CLIMB WELL INTO THE MID 80S AND POSSIBLY
90 DEGREES OVER PORTIONS OF E TX/N LA.
UPPER RIDGING SHOULD AMPLIFY OVER THE CNTRL CONUS BY SUNDAY BEFORE
THE NEXT CLOSED LOW DIGS SE INTO THE SRN ROCKIES SUNDAY BEFORE
MOVING INTO THE SRN PLAINS MONDAY. THIS COULD RESULT IN ANOTHER
SVR THREAT FOR THE REGION BY THE MONDAY/TUESDAY
TIMEFRAME...ALTHOUGH DISCREPENCIES IN TIMING AMONGST THE FASTER
GFS/SLOWER ECMWF PRECLUDES A HIGHER CONFIDENCE ATTM. HOWEVER...THE
PROGS DO CONVERGE ON A PATTERN CHANGE BY MID AND LATE WEEK...WITH COOLER
AND DRIER CONDITIONS SPILLING S ACROSS THE ERN TWO-THIRDS OF THE
CONUS.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 82 64 77 67 / 30 70 40 30
MLU 83 63 77 64 / 20 70 40 20
DEQ 76 58 67 58 / 50 70 40 40
TXK 77 60 71 62 / 40 70 40 30
ELD 80 60 71 60 / 30 70 40 30
TYR 79 65 81 69 / 40 60 30 40
GGG 80 65 80 69 / 30 60 30 40
LFK 84 68 85 71 / 30 50 30 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
538 AM CDT WED APR 22 2015
.DISCUSSION...
AIR MASS MODIFICATION IS UNDERWAY THIS MORNING...WITH AN EXTENSIVE
BAND OF 5-6KFT CIGS HAVING DEVELOPED/SPREAD ENE ALONG AND S OF THE
I-20 CORRIDOR OF N LA/E TX. LOW LEVEL WARM/MOISTURE ADVECTION WILL
CONTINUE TODAY...AS A SRLY LOW LEVEL FLOW INCREASES...AHEAD OF
SFC LOW PRESSURE THAT WILL DEEPEN BY AFTERNOON ALONG THE DRY LINE
OVER NW TX. THIS WILL DRIVE A WARM FRONT NWD TO NEAR THE RED RIVER
OF N TX ESE ACROSS NE TX AND TO NEAR THE AR/LA LINE BY AFTERNOON.
MEANWHILE...A WEAK COLD FRONT WILL DRIFT S TODAY BEFORE
TEMPORARILY BECOMING STATIONARY FROM SRN OK INTO CNTRL AR. THE
MORNING WATER VAPOR IMAGERY REVEALS A SHORTWAVE ROUNDING THE
BACKSIDE OF A LARGE UPPER CLOSED LOW/ATTENDENT LONGWAVE TROUGH
EXTENDING FROM THE NRN GREAT LAKES SW THROUGH THE MIDWEST INTO THE
OK/TX PANHANDLE. THIS SHORTWAVE HAS BEEN DRIVING AN INCREASE IN
ELEVATED CONVECTION ALONG THE FRONT OVER WRN OK...WHICH SHOULD
CONTINUE TO SPREAD SSE ALONG THE FRONTAL ZONE THIS MORNING.
ADDITIONAL REDEVELOPMENT SHOULD OCCUR LATER TODAY AS CONVERGENCE
INCREASES ALONG THE TRIPLE POINT NEAR THE RED RIVER...AND LARGE
SCALE FORCING INCREASES ALONG A SECONDARY SHORTWAVE ON THE WATER
VAPOR IMAGERY OVER SRN NM THAT WILL LIFT NE INTO THE TX PANHANDLE
ATOP THE FLAT SRN PLAINS RIDGE AND ACROSS THE RED RIVER VALLEY.
THE AIR MASS ACROSS THE WARM SECTOR IS EXPECTED TO BECOME
MODERATELY UNSTABLE THIS AFTERNOON...CHARACTERIZED BY MLCAPES OF
1500-2500 J/KG AND STEEP LAPSE RATES. IT REMAINS TO BE SEEN THOUGH
WHETHER THE CURRENT WRN OK CONVECTION MAY HELP INITIATE CONVECTION
EARLIER OVER THE RED RIVER VALLEY...BEFORE MAX DESTABILIZATION
OCCURS...THUS TAPERING THE POTENTIAL INSTABILITY. THE 00Z PROGS
ARE NOT IN GOOD AGREEMENT AT ALL IN REGARDS TO CONVECTION
PLACEMENT/TIMING...ALTHOUGH THE NEW 06Z NAM HAS TRENDED CLOSER TO
THE GFS SOLUTION WITH CONVECTION INCREASING ALONG THE WARM FRONT
OVER NE TX DURING PEAK HEATING. MEANWHILE...THE HRRR IS SUGGESTING
LITTLE IF ANY DEVELOPMENT THIS AFTERNOON NEAR THE TRIPLE
POINT...WITH MORE WIDESPREAD CONVECTION DEVELOPING E OF I-35
ACROSS ECNTRL TX BY MID TO LATE AFTERNOON. NEEDLESS TO
SAY...CONFIDENCE IS LOWER TODAY THAN TUESDAY IN REGARDS TO
CONVECTION INITIATION AND PLACEMENT.
DID MAINTAIN HIGH CHANCE POPS WITH SVR WORDING THIS AFTERNOON NW
OF THE I-30 CORRIDOR ALONG/JUST N OF THE WARM FRONT...TAPERING
CHANCE POPS DOWN A TAD FARTHER E WHERE FRONTAL CONVERGENCE IS A
BIT WEAKER AND THIS REGION IS FARTHER REMOVED FROM THE TWO LOBES
OF SHORTWAVE ENERGY TO OUR N AND W. AN MCS MAY DEVELOP THIS
EVENING ALONG THE RED RIVER VALLEY AND SHIFT ESE ALONG THE FRONT
TONIGHT /PER THE CONSISTENT GFS SOLUTION AND TO SOME EXTENT THE
ECMWF/...WITH THE THREAT OF DAMAGING WINDS/LARGE HAIL POSSIBLE.
DID CONTINUE MENTION OF SVR OVERNIGHT AREAWIDE GIVEN THE
UNCERTAINTY...ALTHOUGH THIS THREAT SHOULD DIMINISH LATE WITH THE
STABILIZING BNDRY LYR. THE SHORT TERM PROGS ALSO SUGGEST A
SLIGHTLY FASTER MOVEMENT OF THE COLD FRONT AS IT BEGINS TO
BACKDOOR SW INTO SE OK/SW AR OVERNIGHT...BEFORE PULLING UP
STATIONARY OVER N LA/E TX THURSDAY. WEAK ISENTROPIC ASCENT ATOP
THE BNDRY MAY RESULT IN SCT CONVECTION DURING THE DAY...ALTHOUGH
THE LACK OF UPPER LEVEL ENERGY SHOULD KEEP QPF AMOUNTS LIGHT. IN
ADDITION...MESOSCALE BNDRYS FROM CONVECTION THIS AFTERNOON AND
TONIGHT MAY PLAY A ROLE IN CONVECTION INITIATION THURSDAY ACROSS
THE WARM SECTOR S OF THE FRONT. BUT ATTM...CONFIDENCE IS LOW IN
REGARDS TO THE PLACEMENT OF THE SVR THREAT...THUS HAVE REMOVED SVR
MENTION FROM THE FORECAST THURSDAY...ALTHOUGH CAN/T RULE OUT AN
ISOLATED SVR STORM WITHIN THE MODERATELY UNSTABLE AIR MASS.
WILL BE WATCHING THE CLOSED SRN CA UPPER LOW AS IT EJECTS NE
ACROSS THE FOUR CORNERS REGION AND OPENS UP THURSDAY
NIGHT...ENTERING THE SRN PLAINS FRIDAY. THE WILL SET UP A STRONG
SW FLOW ALOFT...WITH A 70-80KT MID LEVEL SPEED MAX EJECTING OVER
THE SRN PLAINS FRIDAY AFTERNOON. THIS WILL RESULT IN AN INCREASING
SSWRLY LOW LEVEL FLOW THURSDAY NIGHT/FRIDAY MORNING...THUS LIFTING
THE STATIONARY FRONT BACK N AS A WARM FRONT ACROSS OK/AR FRIDAY
AND HENCE BROADING THE WARM SECTOR. THE W TX DRYLINE WILL MIX E
INTO ERN OK TO JUST W OF THE I-35 CORRIDOR OF CNTRL TX FRIDAY
EVENING...WITH BROAD DIFFLUENCE ALOFT CONTRIBUTING TO SCT TO
NUMEROUS CONVECTION AREAWIDE ESPECIALLY DURING PEAK HEATING. LOW
LEVEL WINDS DO VEER MORE ACROSS THE REGION WELL E OF THE DRYLINE
FRIDAY...WITH A MORE UNIDIRECTIONAL FLOW NOTED ABOVE 850MB. GIVEN
THE STRONG DEEP LYR SHEAR AND MODERATE MLCAPES EXPECTED TO BE IN
PLACE...A MORE PRONOUNCED SVR THREAT WILL BE POSSIBLE WITH
DAMAGING WINDS/ISOLATED TORNADOES. MID LEVEL DRY AIR SHOULD ADVECT
ENE AHEAD OF THE EJECTING TROUGH FRIDAY EVENING...THUS TAPERING
THE CONVECTION FROM W TO E OVERNIGHT...WITH THE DRYLINE PULLING UP
STATIONARY JUST W OF THE REGION. THIS BNDRY SHOULD MIX E ACROSS
THE REGION SATURDAY AS WRLY WINDS INCREASE BENEATH THE MIDWEST SFC
CYCLONE...RESULTING IN PERHAPS THE WARMEST TEMPS SO FAR THIS
SRPING SEASON AS READING CLIMB WELL INTO THE MID 80S AND POSSIBLY
90 DEGREES OVER PORTIONS OF E TX/N LA.
UPPER RIDGING SHOULD AMPLIFY OVER THE CNTRL CONUS BY SUNDAY BEFORE
THE NEXT CLOSED LOW DIGS SE INTO THE SRN ROCKIES SUNDAY BEFORE
MOVING INTO THE SRN PLAINS MONDAY. THIS COULD RESULT IN ANOTHER
SVR THREAT FOR THE REGION BY THE MONDAY/TUESDAY
TIMEFRAME...ALTHOUGH DISCREPENCIES IN TIMING AMONGST THE FASTER
GFS/SLOWER ECMWF PRECLUDES A HIGHER CONFIDENCE ATTM. HOWEVER...THE
PROGS DO CONVERGE ON A PATTERN CHANGE BY MID AND LATE WEEK...WITH COOLER
AND DRIER CONDITIONS SPILLING S ACROSS THE ERN TWO-THIRDS OF THE
CONUS.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 80 64 77 67 / 40 70 40 30
MLU 80 63 77 64 / 30 70 40 20
DEQ 76 58 67 58 / 50 70 40 40
TXK 77 60 71 62 / 40 70 40 30
ELD 78 60 71 60 / 30 70 40 30
TYR 79 65 81 69 / 40 60 30 40
GGG 80 65 80 69 / 40 60 30 40
LFK 84 68 85 71 / 40 50 30 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
645 PM EDT WED APR 22 2015
.SYNOPSIS...
LOW PRESSURE TRACKS EASTWARD THROUGH NORTHERN NEW ENGLAND
WEDNESDAY NIGHT SENDING ANOTHER COLD FRONT THROUGH THE AREA. LOW
PRESSURE LINGERS OVER NORTHERN NEW ENGLAND THROUGH THE WEEKEND
AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE...MONITORING AN AREA OF SHOWERS LIFTING NWD OUT OF MA AT
THIS HOUR. OF CONCERN ARE THE STEEP LOW LEVEL LAPSE RATES IN PLACE
OVER MUCH OF SRN NH. WITH LAPSE RATES APPROACHING 8.5 C/KM
ACCORDING TO THE LATEST RAP MESOANALYSIS...IT WILL NOT TAKE MUCH
CONVECTIVE TO GET GUSTY WINDS TO THE SURFACE. UPSTREAM OBS OF 40
PLUS KT GUSTS AT KORH AND SOME TREE DAMAGE HIGHLIGHT THIS
POTENTIAL EVEN FURTHER. NOT SEEING ANY LIGHTNING CURRENTLY...BUT
WILL HIGHLIGHT GUSTY WINDS IN THE GRIDS THRU 00Z.
RAIN SHOWERS INCREASING OVER NEW HAMPSHIRE AND WESTERN MAINE LATE
THIS AFTERNOON AS AN UPPER LOW OVER THE GREAT LAKES AND A WEAK
COLD FRONT MOVES CLOSER. SOME OF THE RADAR RETURNS ARE HAVING
TROUBLE TRANSLATING TO THE GROUND THIS AFTERNOON OVER NEW
HAMPSHIRE AND WESTERN MAINE, WITH MOST OF THE MORE SIGNIFICANT RAIN
BEING BACK IN VERMONT AND UPSTATE NEW YORK. ATMOSPHERE WILL
GRADUALLY MOISTEN AND MOST AREAS WILL GET SHOWERS THIS EVENING,
DECREASING IN COVERAGE AND BECOMING MORE SCATTERED FROM WEST TO
EAST LATER IN THE NIGHT AS THE COLD FRONT PASSES THROUGH. NOT A
TERRIBLY SIGNIFICANT RAIN EVENT WITH GENERALLY A QUARTER TO HALF
INCH, LOCALLY MORE IN THE MOUNTAINS.
LOOKING FOR ISOLATED TO SCATTERED SHOWERS ON THURSDAY, WITH THE
BETTER CHANCE OF SHOWERS BEING INLAND CLOSER TO THE UPPER LOW
WHICH WILL MOVE FROM THE GREAT LAKES THIS AFTERNOON TO FAR
SOUTHERN QUEBEC THURSDAY. THURSDAY WILL BE A COOL, BREEZY DAY WITH
HIGHS IN THE MID 40S TO LOW 50S LOWER ELEVATIONS.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH 6 PM THURSDAY/...
A CLOSED UPPER LOW OVER THE REGION WILL REMAIN GENERALLY
STATIONARY THROUGH THE PERIOD AS BLOCKING PERSISTS IN THE
ATLANTIC. THIS LOW WILL GENERATE DIURNALLY DRIVEN INSTABILITY SHOWERS.
WITH NORTHWEST WINDS AND DOWNSLOPING...EXPECT DRIER CONDITIONS
DOWNWIND OF THE WESTERN MAINE AND NORTHERN NEW HAMPSHIRE
MOUNTAINS. IN SPITE OF H850 MOISTURE...THE DOWNSLOPING SHOULD
PRODUCE SOME PERIODS OF SUNSHINE FRIDAY AND SATURDAY. A WELL-
MIXED ATMOSPHERE WILL GENERATE GUSTY WINDS ON FRIDAY THAT WILL
REACH 20 MPH. IN THE MOUNTAINS...EXPECT UPSLOPE CONDITIONS AS
MOISTURE WRAPS AROUND THE UPPER LOW THROUGH THE ST LAWRENCE
VALLEY. THIS WILL PRODUCE MOSTLY CLOUDY SKIES WITH SHOWERS THROUGH
THE PERIOD. TEMPERATURES WILL BE COLD ENOUGH TO SUPPORT SNOW
SHOWERS LATER THURSDAY NIGHT INTO EARLY FRIDAY MORNING FOR THE
MOUNTAINS OF WESTERN MAINE AND NORTHERN NEW HAMPSHIRE.
TEMPERATURES WILL BE COOL THURSDAY NIGHT INTO SATURDAY WITH HIGHS
IN THE 40S IN THE MOUNTAINS AND INCREASING TOWARDS THE LOW-MID 50S
ALONG THE COASTAL PLAIN. LOWS WILL RANGE FROM THE UPPER 20S TO
LOWER 30S ON FRIDAY MORNING AND WILL DROP INTO THE 30S AGAIN ON
FRIDAY NIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THE LONGER TERM FROM SATURDAY NIGHT THROUGH THURSDAY CONTINUES TO
FEATURE THE STAGNANT CLOSED UPPER LOW WITH COOL CONDITIONS AND
DIURNALLY-DRIVEN SHOWER ACTIVITY. HAVE FOLLOWED THE SUPER BLEND
VERY CLOSELY. INCREASED POPS FOR PORTLAND AND THE COASTAL PLAIN
FOR MONDAY AS THE UPPER LOW IS EXPECTED TO MOVE DIRECTLY OVER THE
FORECAST AREA. THESE SHOWERS WILL LINGER INTO TUESDAY...BUT THE
TREND TOWARDS LATER TUESDAY WILL BE FOR THE UPPER LOW TO SLIDE
EASTWARD AND ALLOW AN UPPER RIDGE TO BUILD.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
NEAR TERM...
MVFR CONDITIONS EXPECTED FOR MOST AREAS THIS EVENING WITH THE
SHOWER ACTIVITY, ALTHOUGH SOME SPOTS COULD STAY JUST ABOVE MVFR
LEVELS MAINLY IN SOUTHERN NEW HAMPSHIRE. MOST AREAS WILL BE VFR ON
WEDNESDAY ALTHOUGH LOCALIZED MVFR IS EXPECTED IN ANY OF THE
SCATTERED SHOWERS.
SHORT TERM...
EXPECT MOSTLY VFR OUTSIDE OF SHOWER ACTIVITY THROUGH THE PERIOD.
&&
.MARINE...
NEAR TERM...
EXPECT SMALL CRAFT FOR WINDS AND SEAS TONIGHT FOR ALL BUT INNER
WATERS JUST AHEAD OF A WEAK COLD FRONT. THE WINDS WILL SUBSIDE A
BIT ON THURSDAY, BUT THE SEAS WILL REMAIN ABOVE 5 FEET AWAY FROM
THE IMMEDIATE COAST.
SHORT TERM...
NO HEADLINES EXPECTED THROUGH THE PERIOD. VERY STABLE CONDITIONS
CONTINUE OVER THE WATERS AND THE WIND FORECAST MAY NEED TO BE
TRIMMED THURSDAY NIGHT AND FRIDAY.
&&
.FIRE WEATHER...
GENERALLY WET AND COOL WEATHER IS EXPECTED FOR THE REMAINDER OF
THE WEEK.
&&
.HYDROLOGY...
FLOOD WARNING REMAINS IN EFFECT FOR THE KENNEBEC AT AUGUSTA. AFTER
THIS HIGH TIDE CYCLE...RIVER LEVELS SHOULD REMAIN BELOW FLOOD
STAGE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR ANZ150-152-
154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
356 PM EDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 344 PM EDT WED APR 22 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CLOSED UPR LO/
POCKET OF H5 TEMPS NEAR -30C CENTERED OVER ONTARIO TO THE SW OF
JAMES BAY DOWNSTREAM OF HI AMPLITUDE RDG OVER THE ROCKIES. DEEP
MOIST CYC NW FLOW ARND THE CLOSED LO CONTINUES TO IMPACT UPR MI...
DRAWING UNSEASONABLY CHILLY AIR /H85 TEMPS AS LO AS -12 TO -14C THAT
ARE SUFFICIENTLY COLD FOR LES/ INTO THE AREA. THE RESULT HAS BEEN
NMRS SN SHOWERS THAT HAVE BEEN EXACERBATED OVER LAND WITH DAYTIME
HEATING EVEN IN THE ABSENCE OF SGNFT LARGER SCALE FORCING/DEEP LYR
QVECTOR CNVGC.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ESPECIALLY TNGT AS UPR LO DRIFTS SLOWLY TO THE E. TEMPS WL REMAIN
BLO NORMAL THRU THU.
TNGT...UPR LO IS FCST TO DRIFT SLOWLY TO THE E...ALLOWING FOR SLOWLY
RISING H5 HGT/WEAKENING LLVL CYC FLOW. ALTHOUGH SOME GENERAL LARGER
SCALE SUBSIDENCE IS FCST TO DOMINATE...H85 TEMPS REMAINING AS LO AS
ABOUT -13C IN THE PRESENCE OF SOME LINGERNING DEEP MSTR/NOCTURNAL
COOLING WL BE SUFFICIENT TO MAINTAIN LES IN THE FAVORED NW WIND SN
BELTS OVER THE ERN CWA. EXPECT UP TO A COUPLE INCHES OF SN ACCUM IN
THIS AREA. OVER THE W...WARMING H85 TEMPS TO ARND -10C/ LOWERING
SUBSIDENCE INVRN UNDER THE GREATER HGT RISES SHOULD TEND TO CAUSE
THE SN SHOWERS TO DIMINISH IN THAT AREA. HOWEVER...THE PERSISTENT
UPSLOPE NW FLOW AND LINGERING UPSLOPE FLOW WL ALLOW FOR AT LEAST
SOME SCT SN SHOWERS EVEN IN THAT AREA.
THU...PERSISTENT HGT RISES AND SUBSIDENCE/TENDENCY FOR THE LLVL FLOW
TO BECOME MORE ACYC AS WELL AS SOME LLVL DRYING IN THE PRESENCE OF
DAYTIME HEATING WL DIMINISH THE SN SHOWERS W-E. FCST SDNGS INDICATE
THERE WL BE SOME SUNSHINE IN THE AFTN AS WELL WITH HI PRES RDG FCST
TO BLD INTO THE WRN CWA LATER IN THE DAY. TEMPS SHOULD REBOUND INTO
THE 40S OVER THE INTERIOR W AND SCENTRAL AWAY FM LK MODERATION WITH
H85 TEMPS PROGGED TO REACH NEAR -6C ALONG THE WI BORDER BY 00Z FRI.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM EDT WED APR 22 2015
EVEN AS A SFC RIDGE MOVES IN FROM THE W THU NIGHT...ISOLATED SNOW
SHOWERS SHOULD LINGER INTO THE NIGHT IN NW WIND SNOWBELTS NEAR ERN
LAKE SUPERIOR. THIS AS 850MB TEMPS WILL BE AROUND -10C UNDER NW
WINDS. BY FRI MORNING...THE INCREASING INFLUENCE OF THE RIDGE AND
THE WARNING AIRMASS OVERHEAD WILL MAKE FOR A DRY DAY ACROSS THE U.P.
/RULING AT THE 12Z/22 GFS AS AN OUTLIER WITH THE LIGHT PRECIP OVER
THE FAR W/. CLEARING SKIES FROM W TO E THU NIGHT INTO FRI WILL LEAD
TO MIN TEMPS THU NIGHT IN THE TEENS OVER THE INTERIOR W AND IN THE
20S ELSEWHERE. HIGHS ON FRI WILL RANGE FROM THE MID 30S NEAR
CENTRAL/ERN LAKE SUPERIOR TO THE UPPER 40S ALONG THE WI BORDER.
THE WEEKEND LOOKS DRY...SUNNIER AND WARMER AS A SFC LOW SLIDES WELL
S OF THE CWA WITH SFC AND UPPER RIDGING REMAINING OVER THE CWA.
850MB TEMPS HOVERING AROUND 0C SAT AND SUN COMBINED WITH THE PARTLY
CLOUDS SKIES WILL MAKE FOR HIGHS IN THE 40S TO LOW 50S...COOLEST
NEAR LAKE SUPERIOR OVER AND E OF THE KEWEENAW DUE TO E-NE FLOW OFF
THE LAKE. THE RELATIVELY WEAK FLOW AND MORE LIMITED CLOUD COVER WILL
ALLOW MIN TEMPS SAT AND SUN NIGHTS TO BE IN THE MID 20S INLAND TO
LOW 30S ELSEWHERE.
MON ALSO LOOKS FREE OF PRECIP AS RIDGING WEAKENS BUT REMAINS
OVERHEAD. THE ECMWF SUGGEST THE UPPER LOW CURRENTLY IMPACTING THE
REGION MAY RETROGRADE BACK TOWARD THE AREA AFTER SITTING OVER NEW
ENGLAND...BUT THAT WOULD ONLY LEAD TO LIGHT PRECIP OVER THE E IF
THAT DID OCCUR...BUT WILL LEAVE PRECIP OUT OF THE FORECAST FOR NOW.
850MB TEMPS INCREASE A COUPLE OF DEGREES ON MON...BUT TEMPS SHOULD
BE SIMILAR TO SUN AS CLOUD COVER WILL BE INCREASED.
NOT REAL CONFIDENT FOR TUE AND WED AS MODELS SHOW UPPER LEVEL
IMPULSES MOVING THROUGH THE REGION...BUT THERE IS QUITE A BIT OF RUN
TO RUN AND MODEL TO MODEL DISCONTINUITY DURING THIS TIME AS A MORE
SIGNIFICANT PATTERN SHIFT MAY BE STARTING. PRECIP CHANCES ARE
GREATER THAN FRI-MON...BUT NOT HIGH BY ANY MEANS. TEMPS ON TUE LOOK
TO BE SIMILAR TO TUE...BUT MAY COOL DOWN A BIT ON WED. JUST USED A
CONSENSUS OF GUIDANCE FOR THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 349 PM EDT WED APR 22 2015
EXPECT PREDOMINANT MVFR CONDITIONS WITH CHILLY...MOIST NW FLOW OF
AIR ARND DEEP LO PRES IN SE CANADA THRU TNGT. UNDER THE HEAVIER
SHSN... CONDITIONS THRU THIS AFTN WL BE REDUCED INTO THE IFR RANGE.
THERE WL BE IMPROVEMENT TO VFR CONDITIONS ON THU WITH THE CLOSER
APRCH OF SFC HI PRES AND DRIER AIR UNDER LARGE SCALE SUBSIDENCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 355 PM EDT WED APR 22 2015
A FEW NW WINDS GUSTING TO 30 TO NEAR 35KT GALES WILL REMAIN POSSIBLE
OVER N AND CENTRAL LAKE SUPERIOR THIS EVENING. LOW PRESSURE ACROSS
JAMES BAY WILL FILL LATE TONIGHT AND THURSDAY. THE TROUGH ACROSS
LAKE SUPERIOR THIS MORNING...EXTENDING FROM THE JAMES BAY LOW...WILL
SLOWLY BE REPLACED BY A RIDGE. THIS RIDGE WILL REMAIN IN PLACE FROM
FRIDAY THROUGH SUNDAY...EXTENDING FROM STRONG HIGH OVER FAR NORTHERN
CANADA AND GREENLAND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 344 PM EDT WED APR 22 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CLOSED UPR LO/
POCKET OF H5 TEMPS NEAR -30C CENTERED OVER ONTARIO TO THE SW OF
JAMES BAY DOWNSTREAM OF HI AMPLITUDE RDG OVER THE ROCKIES. DEEP
MOIST CYC NW FLOW ARND THE CLOSED LO CONTINUES TO IMPACT UPR MI...
DRAWING UNSEASONABLY CHILLY AIR /H85 TEMPS AS LO AS -12 TO -14C THAT
ARE SUFFICIENTLY COLD FOR LES/ INTO THE AREA. THE RESULT HAS BEEN
NMRS SN SHOWERS THAT HAVE BEEN EXACERBATED OVER LAND WITH DAYTIME
HEATING EVEN IN THE ABSENCE OF SGNFT LARGER SCALE FORCING/DEEP LYR
QVECTOR CNVGC.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ESPECIALLY TNGT AS UPR LO DRIFTS SLOWLY TO THE E. TEMPS WL REMAIN
BLO NORMAL THRU THU.
TNGT...UPR LO IS FCST TO DRIFT SLOWLY TO THE E...ALLOWING FOR SLOWLY
RISING H5 HGT/WEAKENING LLVL CYC FLOW. ALTHOUGH SOME GENERAL LARGER
SCALE SUBSIDENCE IS FCST TO DOMINATE...H85 TEMPS REMAINING AS LO AS
ABOUT -13C IN THE PRESENCE OF SOME LINGERNING DEEP MSTR/NOCTURNAL
COOLING WL BE SUFFICIENT TO MAINTAIN LES IN THE FAVORED NW WIND SN
BELTS OVER THE ERN CWA. EXPECT UP TO A COUPLE INCHES OF SN ACCUM IN
THIS AREA. OVER THE W...WARMING H85 TEMPS TO ARND -10C/ LOWERING
SUBSIDENCE INVRN UNDER THE GREATER HGT RISES SHOULD TEND TO CAUSE
THE SN SHOWERS TO DIMINISH IN THAT AREA. HOWEVER...THE PERSISTENT
UPSLOPE NW FLOW AND LINGERING UPSLOPE FLOW WL ALLOW FOR AT LEAST
SOME SCT SN SHOWERS EVEN IN THAT AREA.
THU...PERSISTENT HGT RISES AND SUBSIDENCE/TENDENCY FOR THE LLVL FLOW
TO BECOME MORE ACYC AS WELL AS SOME LLVL DRYING IN THE PRESENCE OF
DAYTIME HEATING WL DIMINISH THE SN SHOWERS W-E. FCST SDNGS INDICATE
THERE WL BE SOME SUNSHINE IN THE AFTN AS WELL WITH HI PRES RDG FCST
TO BLD INTO THE WRN CWA LATER IN THE DAY. TEMPS SHOULD REBOUND INTO
THE 40S OVER THE INTERIOR W AND SCENTRAL AWAY FM LK MODERATION WITH
H85 TEMPS PROGGED TO REACH NEAR -6C ALONG THE WI BORDER BY 00Z FRI.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM EDT WED APR 22 2015
NAM SHOWS A TROUGH OVER THE EASTERN U.S. 12Z THU WITH MORE TROUGHING
ACROSS THE WEST COAST AND A SHORTWAVE RIDGE OVER THE PLAINS. NAM
SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH THE
CWA ON THU WITH MOISTURE MOVING OUT IN THE AFTERNOON. AS THE
SHORTWAVE RIDGE MOVES TOWARDS THE AREA AND A TROUGH OVER THE EASTERN
U.S. MOVES AWAY...THE WRAPAROUND LAKE ENHANCED PCPN WILL SLOWLY WIND
DOWN AND HAVE IT DRYING OUT FRI AND FRI NIGHT WITH SLOWLY
DIMINISHING POPS IN THE CENTRAL AND EAST ON THU INTO THU NIGHT.
OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES OR POPS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB LOW OVER THE CENTRAL
PLAINS 12Z SAT WITH MORE TROUGHING IN THE WESTERN U.S. THE 500 MB
LOW AND TROUGH IN THE CENTRAL PLAINS GETS SHEARED OUT BY 12Z SUN AND
IS REPLACED BY A SHORTWAVE RIDGE THAT MOVES INTO THE UPPER GREAT
LAKES. THE RIDGE REMAINS OVER THE UPPER GREAT LAKES ON MON WITH
TROUGHING MOVING INTO THE NORTHERN PLAINS. THIS TROUGHING MOVES INTO
THE UPPER GREAT LAKES 12Z TUE. TEMPERATURES WILL STAY BELOW NORMAL
THIS FORECAST PERIOD. WILL CONTINUE WITH DRY WEATHER SAT THROUGH SUN
NIGHT AND THEN GO WITH SLIGHT CHANCE POPS MON THROUGH TUE AS A SFC
FRONT IS WELL OFF TO THE WEST AT THAT TIME AND PRODUCES SOME OVER
RUNNING PCPN THAT IS OFF TO THE WEST MOSTLY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 349 PM EDT WED APR 22 2015
EXPECT PREDOMINANT MVFR CONDITIONS WITH CHILLY...MOIST NW FLOW OF
AIR ARND DEEP LO PRES IN SE CANADA THRU TNGT. UNDER THE HEAVIER
SHSN... CONDITIONS THRU THIS AFTN WL BE REDUCED INTO THE IFR RANGE.
THERE WL BE IMPROVEMENT TO VFR CONDITIONS ON THU WITH THE CLOSER
APRCH OF SFC HI PRES AND DRIER AIR UNDER LARGE SCALE SUBSIDENCE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EDT WED APR 22 2015
A FEW NW WINDS GUSTING TO 30 TO NEAR 35KT GALES WILL REMAIN POSSIBLE
OVER N AND CENTRAL LAKE SUPERIOR TODAY. LOW PRESSURE ACROSS JAMES
BAY WILL FILL LATE TONIGHT AND THURSDAY. THE TROUGH ACROSS LAKE
SUPERIOR THIS MORNING...EXTENDING FROM THE JAMES BAY LOW...WILL
SLOWLY BE REPLACED BY A RIDGE. THIS RIDGE WILL REMAIN IN PLACE FROM
FRIDAY THROUGH SUNDAY...EXTENDING FROM STRONG HIGH OVER FAR NORTHERN
CANADA AND GREENLAND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...07
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
345 PM EDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 344 PM EDT WED APR 22 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CLOSED UPR LO/
POCKET OF H5 TEMPS NEAR -30C CENTERED OVER ONTARIO TO THE SW OF
JAMES BAY DOWNSTREAM OF HI AMPLITUDE RDG OVER THE ROCKIES. DEEP
MOIST CYC NW FLOW ARND THE CLOSED LO CONTINUES TO IMPACT UPR MI...
DRAWING UNSEASONABLY CHILLY AIR /H85 TEMPS AS LO AS -12 TO -14C THAT
ARE SUFFICIENTLY COLD FOR LES/ INTO THE AREA. THE RESULT HAS BEEN
NMRS SN SHOWERS THAT HAVE BEEN EXACERBATED OVER LAND WITH DAYTIME
HEATING EVEN IN THE ABSENCE OF SGNFT LARGER SCALE FORCING/DEEP LYR
QVECTOR CNVGC.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ESPECIALLY TNGT AS UPR LO DRIFTS SLOWLY TO THE E. TEMPS WL REMAIN
BLO NORMAL THRU THU.
TNGT...UPR LO IS FCST TO DRIFT SLOWLY TO THE E...ALLOWING FOR SLOWLY
RISING H5 HGT/WEAKENING LLVL CYC FLOW. ALTHOUGH SOME GENERAL LARGER
SCALE SUBSIDENCE IS FCST TO DOMINATE...H85 TEMPS REMAINING AS LO AS
ABOUT -13C IN THE PRESENCE OF SOME LINGERNING DEEP MSTR/NOCTURNAL
COOLING WL BE SUFFICIENT TO MAINTAIN LES IN THE FAVORED NW WIND SN
BELTS OVER THE ERN CWA. EXPECT UP TO A COUPLE INCHES OF SN ACCUM IN
THIS AREA. OVER THE W...WARMING H85 TEMPS TO ARND -10C/ LOWERING
SUBSIDENCE INVRN UNDER THE GREATER HGT RISES SHOULD TEND TO CAUSE
THE SN SHOWERS TO DIMINISH IN THAT AREA. HOWEVER...THE PERSISTENT
UPSLOPE NW FLOW AND LINGERING UPSLOPE FLOW WL ALLOW FOR AT LEAST
SOME SCT SN SHOWERS EVEN IN THAT AREA.
THU...PERSISTENT HGT RISES AND SUBSIDENCE/TENDENCY FOR THE LLVL FLOW
TO BECOME MORE ACYC AS WELL AS SOME LLVL DRYING IN THE PRESENCE OF
DAYTIME HEATING WL DIMINISH THE SN SHOWERS W-E. FCST SDNGS INDICATE
THERE WL BE SOME SUNSHINE IN THE AFTN AS WELL WITH HI PRES RDG FCST
TO BLD INTO THE WRN CWA LATER IN THE DAY. TEMPS SHOULD REBOUND INTO
THE 40S OVER THE INTERIOR W AND SCENTRAL AWAY FM LK MODERATION WITH
H85 TEMPS PROGGED TO REACH NEAR -6C ALONG THE WI BORDER BY 00Z FRI.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM EDT WED APR 22 2015
NAM SHOWS A TROUGH OVER THE EASTERN U.S. 12Z THU WITH MORE TROUGHING
ACROSS THE WEST COAST AND A SHORTWAVE RIDGE OVER THE PLAINS. NAM
SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH THE
CWA ON THU WITH MOISTURE MOVING OUT IN THE AFTERNOON. AS THE
SHORTWAVE RIDGE MOVES TOWARDS THE AREA AND A TROUGH OVER THE EASTERN
U.S. MOVES AWAY...THE WRAPAROUND LAKE ENHANCED PCPN WILL SLOWLY WIND
DOWN AND HAVE IT DRYING OUT FRI AND FRI NIGHT WITH SLOWLY
DIMINISHING POPS IN THE CENTRAL AND EAST ON THU INTO THU NIGHT.
OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES OR POPS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB LOW OVER THE CENTRAL
PLAINS 12Z SAT WITH MORE TROUGHING IN THE WESTERN U.S. THE 500 MB
LOW AND TROUGH IN THE CENTRAL PLAINS GETS SHEARED OUT BY 12Z SUN AND
IS REPLACED BY A SHORTWAVE RIDGE THAT MOVES INTO THE UPPER GREAT
LAKES. THE RIDGE REMAINS OVER THE UPPER GREAT LAKES ON MON WITH
TROUGHING MOVING INTO THE NORTHERN PLAINS. THIS TROUGHING MOVES INTO
THE UPPER GREAT LAKES 12Z TUE. TEMPERATURES WILL STAY BELOW NORMAL
THIS FORECAST PERIOD. WILL CONTINUE WITH DRY WEATHER SAT THROUGH SUN
NIGHT AND THEN GO WITH SLIGHT CHANCE POPS MON THROUGH TUE AS A SFC
FRONT IS WELL OFF TO THE WEST AT THAT TIME AND PRODUCES SOME OVER
RUNNING PCPN THAT IS OFF TO THE WEST MOSTLY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 729 AM EDT WED APR 22 2015
SPOTTY SNOW SHOWERS IN PERSISTENT NW FLOW HAS RESULTED IN VARIABLE
CONDITIONS RANGING MAINLY FROM MVFR TO IFR...WITH THE TEMPORARY VFR
CEILINGS AND VIS IN BETWEEN SNOW SHOWERS. DUE TO THE HIGHLY VARIABLE
REGIME...TEMPO GROUPS WILL REMAIN NECESSARY. EXPECT IMPROVING
CONDITIONS DURING THE DAYTIME HOURS WITH THE ASSISTANCE OF THE LATE
APRIL SUN...WITH CEILINGS IMPROVING A CATEGORY /MAINLY TO MVFR...IF
NOT VFR AT SAW IN THE LESS FAVORABLE NW FLOW/. THE SFC LOW OVER
JAMES BAY THIS MORNING WILL SLOWLY WEAKEN...AND A STRONG RIDGE OF
HIGH PRESSURE ACROSS N AND CENTRAL CANADA WILL BE BUILDING A RIDGE
CLOSER TO THE AREA. LOOK FOR IMPROVING CONDITIONS W TO E LATER
TONIGHT AS DRIER AIR NEARS. MVFR TO VFR CEILINGS/VIS ARE ANTICIPATED
AT IWD AROUND 12Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EDT WED APR 22 2015
A FEW NW WINDS GUSTING TO 30 TO NEAR 35KT GALES WILL REMAIN POSSIBLE
OVER N AND CENTRAL LAKE SUPERIOR TODAY. LOW PRESSURE ACROSS JAMES
BAY WILL FILL LATE TONIGHT AND THURSDAY. THE TROUGH ACROSS LAKE
SUPERIOR THIS MORNING...EXTENDING FROM THE JAMES BAY LOW...WILL
SLOWLY BE REPLACED BY A RIDGE. THIS RIDGE WILL REMAIN IN PLACE FROM
FRIDAY THROUGH SUNDAY...EXTENDING FROM STRONG HIGH OVER FAR NORTHERN
CANADA AND GREENLAND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...07
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
302 AM EDT WED APR 22 2015
.UPDATE...
ISSUED AT 1114 PM EDT TUE APR 21 2015
PREVIOUS SHORT TERM DISCUSSION SPELLED OUT THE SITUATION QUITE WELL
FOR OVERNIGHT INTO WED. AFTER CONSIDERING THE DEEP MOISTURE ON 00Z
KINL/CWPL SOUNDINGS...850MB TEMPS FALLING AT LEAST ANOTHER 2C
OVERNIGHT AND CONTINUED CYCLONIC FLOW...FEEL ADVY ACCUMULATIONS ARE
LIKELY TO OCCUR OVER A DECENT AREA OF GOGEBIC/ONTONAGON COUNTIES...
IN PARTICULAR THE HIGH TERRAIN. WOULD NOT BE SURPRISED TO SEE A FEW
SPOTS IN THE HIGH TERRAIN TOP 5 INCHES BY NOON WED. PROBABLY COULD
HAVE EXTENDED ADVY N AND E THRU THE KEWEENAW AND INTO BARAGA COUNTY
AS AIR MASS PASSING OVER THE LAKE WILL BE A LITTLE COLDER THAN DOWN
TOWARD KIWD. RECENT RADAR TRENDS ARE ALSO A CONCERN WITH INCREASING
COVERAGE AND INTENSITY OF SNOW IN THAT AREA. ALSO BUMPED UP SNOW
ACCUMLATIONS INTO THE ERN FCST AREA...E OF MARQUETTE AS 850MB
THERMAL TROF WITH TEMPS AS LOW AS -14C WILL BE AIMING SE ACROSS THE
LAKE AND INTO THAT AREA WED MORNING. HAVE AMOUNTS UP TO AROUND 3
INCHES IN THAT AREA BY LATE WED MORNING...BUT THAT COULD END UP
BEING TOO CONSERVATIVE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 352 PM EDT TUE APR 21 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CLOSED UPR LO OVER
THE UPR LKS DOWNSTREAM OF HI AMPLITUDE UPR RDG OVER WRN NAMERICA.
COMBINATION OF DEEP CYC FLOW W TO NW FLOW AND INSTABILITY ENHANCED
BY DAYTIME HEATING UNDER ACCOMAPANYING THERMAL TROF /12Z H5 TEMP AT
GRB WAS -31C/ AND DEEP MSTR SHOWN ON THE 12Z RAOBS IS RESULTING IN
SCT-NMRS SN SHOWERS THAT ARE MIXED WITH RA IN THE WARMER LOCATIONS.
BUT COLDER CLD TOP TEMPS/MORE WIDESRPEAD SN SHOWERS ARE CONFINED
MAINLY TO NW ONTARIO/FAR NRN MN IN AREA WHERE MODELS INDICATE DEEP
QVECTOR CNVGC.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS AND POTENTIAL SN
ACCUMS ASSOCIATED WITH DEEP CYC...MOIST NW FLOW ARND SLOW MOVING
CLOSED LO TO THE NE OF UPR MI.
CLOSED LO CENTERED OVER ERN LK SUP THIS AFTN IS FCST TO DRIFT SLOWLY
TO THE NE AND TO JUST S OF JAMES BAY ON WED. ALTHOUGH ACCOMPANYING
DEEP LYR QVECTOR CNVGC THAT IS SUPPORTING COLDER CLD TOPS TO THE NW
IS FCST TO REMAIN TO THE N OF UPR MI...PERSISTENT MOIST...CYC NW
FLOW ARND THIS FEATURE WL MAINTAIN AT LEAST CHC POPS OVER THE CWA
THRU WED...WITH THE LOWER POPS GENERALLY OVER THE SCENTRAL AND THE
HIER POPS OVER THE HIER TERRAIN OF THE NW WITH UPSLOPE WIND
COMPONENT. BUT LOSS OF DAYTIME HEATING TNGT WL CAUSE THE
CHARACTER OF THE SHOWER PATTERN TO TRANSITIONS FM ONE THAT SUPPORTS
THE HIER POPS OVER THE INTERIOR THIS AFTN TO A MORE WINTRY LES
LOOK TNGT. IN FACT...THE NW FLOW IS PROGGED TO ADVECT H85 TEMPS AS
LO AS -13 TO -14C OVER THE KEWEENAW BY 12Z WED...TEMPS LO ENUF TO
SUPPORT LES AND INCRS SN/WATER RATIOS ONCE THE EFFECT OF DAYTIME
INSOLATION HAS FADED. OVER THE HIER TERRAIN OF THE W...THERE WL
LIKELY BE SEVERAL INCHES OF WET SN ACCUM TNGT INTO WED MRNG EVEN IN
THE ABSENCE OF SGNFT LARGER SCALE FORCING. OPTED TO ISSUE AN SPS
TO ALERT THE PUBLIC TO THE POTENTIAL OF SOME SLUSHY SN ACCUMS ON
ROADS LATER THIS EVNG INTO WED MRNG. DAYTIME HEATING ON WED WL
BRING ABOUT A RETURN TO A MORE LAND BASED INSTABILITY SHOWER
PATTERN. BUT SOMEWHAT HIER HGTS/SHARPENING MID LVL INVRN FARTHER FM
THE SLOWLY DEPARTING CLOSED LO THAT RESTRICTS DESTABILIZATION WL
TEND TO LIMIT COVERAGE/INTENSITY OF THE SHOWERS AS COMPARED TO TODAY.
ALTHOUGH H85 TEMPS ARE FCST TO MODERATE TO -10C TO -12C...MAX TEMPS
ON WED WL HOLD IN THE 30S EXPECT WHERE SOME DOWNSLOPE WARMING AIDS
DIURNAL TEMP RECOVERY INTO THE LO 40S OVER THE SCENTRAL. THERE COULD
BE SOME RECORD LO MAX TEMPS ON WED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM EDT WED APR 22 2015
NAM SHOWS A TROUGH OVER THE EASTERN U.S. 12Z THU WITH MORE TROUGHING
ACROSS THE WEST COAST AND A SHORTWAVE RIDGE OVER THE PLAINS. NAM
SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH THE
CWA ON THU WITH MOISTURE MOVING OUT IN THE AFTERNOON. AS THE
SHORTWAVE RIDGE MOVES TOWARDS THE AREA AND A TROUGH OVER THE EASTERN
U.S. MOVES AWAY...THE WRAPAROUND LAKE ENHANCED PCPN WILL SLOWLY WIND
DOWN AND HAVE IT DRYING OUT FRI AND FRI NIGHT WITH SLOWLY
DIMINISHING POPS IN THE CENTRAL AND EAST ON THU INTO THU NIGHT.
OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES OR POPS.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB LOW OVER THE CENTRAL
PLAINS 12Z SAT WITH MORE TROUGHING IN THE WESTERN U.S. THE 500 MB
LOW AND TROUGH IN THE CENTRAL PLAINS GETS SHEARED OUT BY 12Z SUN AND
IS REPLACED BY A SHORTWAVE RIDGE THAT MOVES INTO THE UPPER GREAT
LAKES. THE RIDGE REMAINS OVER THE UPPER GREAT LAKES ON MON WITH
TROUGHING MOVING INTO THE NORTHERN PLAINS. THIS TROUGHING MOVES INTO
THE UPPER GREAT LAKES 12Z TUE. TEMPERATURES WILL STAY BELOW NORMAL
THIS FORECAST PERIOD. WILL CONTINUE WITH DRY WEATHER SAT THROUGH SUN
NIGHT AND THEN GO WITH SLIGHT CHANCE POPS MON THROUGH TUE AS A SFC
FRONT IS WELL OFF TO THE WEST AT THAT TIME AND PRODUCES SOME OVER
RUNNING PCPN THAT IS OFF TO THE WEST MOSTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1231 AM EDT WED APR 22 2015
AS DEEP MOISTURE LINGERS AND COLDER AIR ARRIVES OVERNIGHT...SHSN
WILL INCREASE IN FREQUENCY AND INTENSITY AT KIWD/KCMX UNDER USPLOPE
NW WIND OFF LAKE SUPERIOR. EXPECT PREVAILING IFR CONDITIONS AT BOTH
TERMINALS THRU MID MORNING. TYPICAL FOR SHSN...THERE WILL BE
FLUCTUATION WITH SOME BRIEF PERIODS OF LIFR AND MVFR...THOUGH LIFR
MAY BE MORE FREQUENT IN THE FEW HRS EITHER SIDE OF SUNRISE. INTO THE
AFTN...EXPECT IMPROVEMENT TO MVFR AS SHSN INTENSITY DIMINISHES.
DOWNSLOPE NATURE OF THE NW FLOW WILL WORK TO LIMIT THE POTENTIAL FOR
LOWER VIS/CIG AT KSAW. WHILE MVFR CONDITIONS SHOULD PREVAIL...THERE
MAY BE BRIEF PERIODS OF IFR THRU MID MORNING. MVFR CONDITIONS WILL
PERSIST AT ALL TERMINALS THRU THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EDT TUE APR 21 2015
NORTHWESTERLY WINDS UP TO 30 KNOTS WILL CONTINUE OVER LAKE SUPERIOR
THROUGH THURSDAY MORNING. THERE COULD BE A FEW PERIODS OF GALE
FORCE GUSTS TO 35KTS LATE TONIGHT INTO WEDNESDAY...BUT THEY
SHOULDN/T BE WIDESPREAD. HIGH PRESSURE WILL BEGIN TO BUILD INTO
WESTERN LAKE SUPERIOR THURSDAY AFTERNOON/NIGHT AND LEAD TO
GRADUALLY DIMINISHING WINDS INTO FRIDAY. LIGHT NORTHERLY WINDS UP
TO 15KTS ARE EXPECTED THIS WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL NOON EDT /11 AM CDT/ TODAY FOR
MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...ROLFSON
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1232 AM EDT WED APR 22 2015
.UPDATE...
ISSUED AT 1114 PM EDT TUE APR 21 2015
PREVIOUS SHORT TERM DISCUSSION SPELLED OUT THE SITUATION QUITE WELL
FOR OVERNIGHT INTO WED. AFTER CONSIDERING THE DEEP MOISTURE ON 00Z
KINL/CWPL SOUNDINGS...850MB TEMPS FALLING AT LEAST ANOTHER 2C
OVERNIGHT AND CONTINUED CYCLONIC FLOW...FEEL ADVY ACCUMULATIONS ARE
LIKELY TO OCCUR OVER A DECENT AREA OF GOGEBIC/ONTONAGON COUNTIES...
IN PARTICULAR THE HIGH TERRAIN. WOULD NOT BE SURPRISED TO SEE A FEW
SPOTS IN THE HIGH TERRAIN TOP 5 INCHES BY NOON WED. PROBABLY COULD
HAVE EXTENDED ADVY N AND E THRU THE KEWEENAW AND INTO BARAGA COUNTY
AS AIR MASS PASSING OVER THE LAKE WILL BE A LITTLE COLDER THAN DOWN
TOWARD KIWD. RECENT RADAR TRENDS ARE ALSO A CONCERN WITH INCREASING
COVERAGE AND INTENSITY OF SNOW IN THAT AREA. ALSO BUMPED UP SNOW
ACCUMLATIONS INTO THE ERN FCST AREA...E OF MARQUETTE AS 850MB
THERMAL TROF WITH TEMPS AS LOW AS -14C WILL BE AIMING SE ACROSS THE
LAKE AND INTO THAT AREA WED MORNING. HAVE AMOUNTS UP TO AROUND 3
INCHES IN THAT AREA BY LATE WED MORNING...BUT THAT COULD END UP
BEING TOO CONSERVATIVE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 352 PM EDT TUE APR 21 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CLOSED UPR LO OVER
THE UPR LKS DOWNSTREAM OF HI AMPLITUDE UPR RDG OVER WRN NAMERICA.
COMBINATION OF DEEP CYC FLOW W TO NW FLOW AND INSTABILITY ENHANCED
BY DAYTIME HEATING UNDER ACCOMAPANYING THERMAL TROF /12Z H5 TEMP AT
GRB WAS -31C/ AND DEEP MSTR SHOWN ON THE 12Z RAOBS IS RESULTING IN
SCT-NMRS SN SHOWERS THAT ARE MIXED WITH RA IN THE WARMER LOCATIONS.
BUT COLDER CLD TOP TEMPS/MORE WIDESRPEAD SN SHOWERS ARE CONFINED
MAINLY TO NW ONTARIO/FAR NRN MN IN AREA WHERE MODELS INDICATE DEEP
QVECTOR CNVGC.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS AND POTENTIAL SN
ACCUMS ASSOCIATED WITH DEEP CYC...MOIST NW FLOW ARND SLOW MOVING
CLOSED LO TO THE NE OF UPR MI.
CLOSED LO CENTERED OVER ERN LK SUP THIS AFTN IS FCST TO DRIFT SLOWLY
TO THE NE AND TO JUST S OF JAMES BAY ON WED. ALTHOUGH ACCOMPANYING
DEEP LYR QVECTOR CNVGC THAT IS SUPPORTING COLDER CLD TOPS TO THE NW
IS FCST TO REMAIN TO THE N OF UPR MI...PERSISTENT MOIST...CYC NW
FLOW ARND THIS FEATURE WL MAINTAIN AT LEAST CHC POPS OVER THE CWA
THRU WED...WITH THE LOWER POPS GENERALLY OVER THE SCENTRAL AND THE
HIER POPS OVER THE HIER TERRAIN OF THE NW WITH UPSLOPE WIND
COMPONENT. BUT LOSS OF DAYTIME HEATING TNGT WL CAUSE THE
CHARACTER OF THE SHOWER PATTERN TO TRANSITIONS FM ONE THAT SUPPORTS
THE HIER POPS OVER THE INTERIOR THIS AFTN TO A MORE WINTRY LES
LOOK TNGT. IN FACT...THE NW FLOW IS PROGGED TO ADVECT H85 TEMPS AS
LO AS -13 TO -14C OVER THE KEWEENAW BY 12Z WED...TEMPS LO ENUF TO
SUPPORT LES AND INCRS SN/WATER RATIOS ONCE THE EFFECT OF DAYTIME
INSOLATION HAS FADED. OVER THE HIER TERRAIN OF THE W...THERE WL
LIKELY BE SEVERAL INCHES OF WET SN ACCUM TNGT INTO WED MRNG EVEN IN
THE ABSENCE OF SGNFT LARGER SCALE FORCING. OPTED TO ISSUE AN SPS
TO ALERT THE PUBLIC TO THE POTENTIAL OF SOME SLUSHY SN ACCUMS ON
ROADS LATER THIS EVNG INTO WED MRNG. DAYTIME HEATING ON WED WL
BRING ABOUT A RETURN TO A MORE LAND BASED INSTABILITY SHOWER
PATTERN. BUT SOMEWHAT HIER HGTS/SHARPENING MID LVL INVRN FARTHER FM
THE SLOWLY DEPARTING CLOSED LO THAT RESTRICTS DESTABILIZATION WL
TEND TO LIMIT COVERAGE/INTENSITY OF THE SHOWERS AS COMPARED TO TODAY.
ALTHOUGH H85 TEMPS ARE FCST TO MODERATE TO -10C TO -12C...MAX TEMPS
ON WED WL HOLD IN THE 30S EXPECT WHERE SOME DOWNSLOPE WARMING AIDS
DIURNAL TEMP RECOVERY INTO THE LO 40S OVER THE SCENTRAL. THERE COULD
BE SOME RECORD LO MAX TEMPS ON WED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM EDT TUE APR 21 2015
THE UPPER LOW THAT IS CURRENTLY AFFECTING THE AREA WILL SHIFT EAST
INTO THE CANADIAN MARITIMES SHORTLY AFTER THE START OF THE LONG TERM
PERIOD. THIS WILL LEAVE THE AREA BETWEEN THAT UPPER LOW AND AN UPPER
RIDGE IN THE CENTRAL/SOUTHERN PLAINS. THUS...THE AREA WILL BE UNDER
NORTHWESTERLY FLOW ALOFT FOR MOST DAYS THROUGH THE UPCOMING WEEKEND.
WITH A SURFACE RIDGE STRETCHING SOUTH FROM A HIGH IN NORTHERN CANADA
MOVING INTO THE AREA BY FRIDAY AND FRIDAY NIGHT...EXPECT DRIER AIR
TO GRADUALLY MOVE INTO THE REGION AND DIMINISH THE PRECIPITATION
POTENTIAL AND LEAD TO A DRY WEEKEND (ALTHOUGH THERE ARE HINTS OF A
WEAK DISTURBANCE BRINGING AN ISOLATED SHOWER TO THE FAR WESTERN U.P.
LATE FRIDAY NIGHT INTO SATURDAY MORNING). WITH THE MAIN UPPER LOW
SHIFTING EAST...TEMPERATURES WILL SLOWLY WARM BUT STILL STAY BELOW
NORMAL FOR LATE APRIL (AIDED BY THE LIGHT NORTHERLY FLOW OFF LAKE
SUPERIOR).
HEADING INTO NEXT WEEK...THE UPPER LOW CURRENTLY OVER THE GULF OF
ALASKA WILL MOVE INTO THE PACIFIC NORTHWEST OVER THE NEXT 24-48HRS
AND THEN INTO THE CENTRAL CONUS ON MONDAY. AS THE WAVE CONTINUES
EAST...IT WILL INTERACT WITH THE UPPER LOW NEAR THE CANADIAN
MARITIMES AND RE-ESTABLISH THE UPPER TROUGH OVER THE EASTERN CONUS.
THIS WILL KEEP BELOW NORMAL TEMPERATURES IN PLACE INTO NEXT WEEK AND
POSSIBLY LEAD TO SOME SHOWERS AROUND THE GREAT LAKES REGION.
OVERALL...FAIRLY COOL AND QUIET END TO APRIL WITH NO HAZARDOUS
WEATHER EXPECTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1231 AM EDT WED APR 22 2015
AS DEEP MOISTURE LINGERS AND COLDER AIR ARRIVES OVERNIGHT...SHSN
WILL INCREASE IN FREQUENCY AND INTENSITY AT KIWD/KCMX UNDER USPLOPE
NW WIND OFF LAKE SUPERIOR. EXPECT PREVAILING IFR CONDITIONS AT BOTH
TERMINALS THRU MID MORNING. TYPICAL FOR SHSN...THERE WILL BE
FLUCTUATION WITH SOME BRIEF PERIODS OF LIFR AND MVFR...THOUGH LIFR
MAY BE MORE FREQUENT IN THE FEW HRS EITHER SIDE OF SUNRISE. INTO THE
AFTN...EXPECT IMPROVEMENT TO MVFR AS SHSN INTENSITY DIMINISHES.
DOWNSLOPE NATURE OF THE NW FLOW WILL WORK TO LIMIT THE POTENTIAL FOR
LOWER VIS/CIG AT KSAW. WHILE MVFR CONDITIONS SHOULD PREVAIL...THERE
MAY BE BRIEF PERIODS OF IFR THRU MID MORNING. MVFR CONDITIONS WILL
PERSIST AT ALL TERMINALS THRU THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EDT TUE APR 21 2015
NORTHWESTERLY WINDS UP TO 30 KNOTS WILL CONTINUE OVER LAKE SUPERIOR
THROUGH THURSDAY MORNING. THERE COULD BE A FEW PERIODS OF GALE
FORCE GUSTS TO 35KTS LATE TONIGHT INTO WEDNESDAY...BUT THEY
SHOULDN/T BE WIDESPREAD. HIGH PRESSURE WILL BEGIN TO BUILD INTO
WESTERN LAKE SUPERIOR THURSDAY AFTERNOON/NIGHT AND LEAD TO
GRADUALLY DIMINISHING WINDS INTO FRIDAY. LIGHT NORTHERLY WINDS UP
TO 15KTS ARE EXPECTED THIS WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL NOON EDT /11 AM CDT/ TODAY FOR
MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...ROLFSON
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS BILLINGS MT
325 PM MDT WED APR 22 2015
.SHORT TERM...VALID FOR THU AND FRI...
A DEEP UPPER TROUGH WILL WORK ACROSS SOUTHERN CANADA TONIGHT. THE
SOUTHERN EXTENT OF THE WAVE WILL SWING ACROSS THE FORECAST AREA. A
FLATTENING UPPER RIDGE WILL MOVE EAST AND DEFLECT MOST OF THE
ENERGY OVER NORTHERN MONTANA. HRRR WAS PUSHING SHOWERS WITH
EMBEDDED THUNDERSTORMS ACROSS THE WEST INTO CENTRAL ZONES. HAVE
PUSHED LOW POPS INTO BILLINGS THIS EVENING BASED ON THE HRRR
SOLUTION AND RADAR RETURNS DEVELOPING OVER THE WEST.
WILL KEEP SCATTERED POPS IN THE ZONES THURSDAY AND FRIDAY. THE
STRONGEST ENERGY WILL MOVE INTO THE WEST FRIDAY AFTERNOON AND
EVENING. LOW LEVEL EASTERLY WINDS WILL BE ABLE TO PREVENT THE
DEWPOINTS FROM DRYING OUT. MODEL PROGGED PWATS WERE AROUND 2
STANDARD DEVIATIONS ABOVE NORMAL...ESPECIALLY OVER THE EAST.
INSTABILITY WAS NOT EXPECTED TO BE TREMENDOUS...BUT ENOUGH TO
WARRANT ISOLATED THUNDER MENTION. WEAK MID LEVEL FLOW ON THURSDAY
WILL CAUSE PULSING...SHORT LIVED CELLS. CELLS WILL HAVE BETTER
MOVEMENT AND MORE ORGANIZATION ON FRIDAY. TEMPERATURES WILL BE IN
THE MID 60S TO RIGHT AROUND 70 BOTH THURSDAY AND FRIDAY. TWH
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
PATTERN CONTINUES TO LOOK UNSETTLED GOING INTO EARLY NEXT WEEK.
NEGATIVELY TILTED SHORTWAVE EMBEDDED IN SOUTHWEST FLOW ALOFT WILL
BRING A CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS ON SATURDAY.
STRONGER UPPER LOW DEVELOPS OVER IDAHO AND SLIDES SOUTHEAST TOWARD
COLORADO SATURDAY NIGHT AND SUNDAY WITH 700MB LOW DEVELOPING OVER
NORTHERN WYOMING. THIS IS A GOOD PRECIPITATION PATTERN FOR THE
AREA LATE SATURDAY NIGHT THROUGH SUNDAY NIGHT. INCREASED
PRECIPITATION CHANCES TO LIKELY IN MOST LOCATIONS BY EARLY SUNDAY
MORNING...TAPERING OFF FROM NORTHWEST TO SOUTHEAST SUNDAY NIGHT
INTO MONDAY. MODELS INDICATING MANY AREAS COULD SEE HALF AN INCH
OF PRECIPITATION WITH THIS SYSTEM...WITH LOCALLY HEAVIER AMOUNTS
POSSIBLE. THIS IS A PRETTY WARM PACIFIC SYSTEM AND DYNAMIC
COOLING IS HAMPERED BY STRONGEST JET FORCING STAYING SOUTH OF THE
AREA...SO KEPT PRECIPITATION TYPE MAINLY RAIN BELOW 6000 FEET.
MODELS ALL GRABBING ONTO SOME SORT OF RIDGING TUESDAY INTO
THURSDAY NEXT WEEK FOR WARMER AND DRIER CONDITIONS. CHAMBERS
&&
.AVIATION...
LIGHT EASTERLY WINDS WILL INCREASE SLIGHTLY THIS EVENING AHEAD OF
A DISTURBANCE CROSSING THE REGION EARLY THURSDAY. WINDS WILL SHIFT
WEST TO NORTHWESTERLY AND BECOME MORE GUSTY WITH FROPA. SHOWERS
ARE DEVELOPING OVER THE MOUNTAINS INTO TONIGHT...SOME WILL REACH
NEARBY PLAINS...WITH LOCALIZED MVFR POSSIBLE. THE WAVE CROSSING
THE REGION THURSDAY WILL BRING ANOTHER SLIGHT CHANCE FOR SHOWERS
ACROSS THE REGION. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 046/067 044/068 044/059 039/055 038/066 042/072 044/072
22/T 23/T 43/T 66/R 42/W 11/B 10/B
LVM 039/067 038/066 038/055 035/053 031/065 037/072 040/070
34/T 34/T 54/T 66/R 42/W 11/B 10/B
HDN 040/069 039/071 039/061 039/054 038/066 037/073 043/072
02/T 22/T 33/T 56/R 42/W 11/B 10/B
MLS 038/069 038/070 040/060 039/055 039/066 037/070 042/069
02/T 11/B 35/T 56/R 52/W 11/B 11/B
4BQ 037/071 038/070 041/061 040/055 039/065 039/069 041/068
02/T 22/T 25/T 57/R 63/W 11/B 11/U
BHK 032/065 034/064 036/058 040/053 039/062 038/066 041/064
02/T 11/B 25/T 56/R 63/W 11/B 11/B
SHR 039/067 039/067 039/056 037/050 036/063 037/069 039/066
02/T 22/T 22/T 47/R 52/W 11/B 10/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
627 PM CDT THU APR 23 2015
.SYNOPSIS...
ISSUED AT 320 PM CDT THU APR 23 2015
SPLIT UPPER LEVEL PATTERN OVER THE WESTERN HALF OF THE CONUS...BROAD
CYCLONIC FLOW TO THE EAST. A SHORTWAVE RIDGE WAS TRANSLATING EAST
ACROSS THE CENTRAL PLAINS...IN ADVANCE OF A STRONG PV MAX SLOWLY
MOVING NORTHEASTWARD ACROSS THE DESERT SOUTHWEST. THE ASSOCIATED
HEIGHT FALLS WITH THIS PATTERN WERE SUPPORTING THE GRADUAL DEEPENING
OF A LEE SIDE SFC TROUGH FROM NORTHEAST COLORADO THROUGH THE WESTERN
NEBRASKA PANHANDLE. EAST OF THIS TROUGH WINDS WERE BREEZY OUT OF THE
SOUTH...TRANSPORTING LOW LEVEL MOISTURE INTO THE CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 320 PM CDT THU APR 23 2015
CUMULUS CLOUDS AND A FEW SHOWERS AND THUNDERSTORMS HAVE ALREADY
DEVELOPED JUST WEST OF THE CWA EARLY THIS AFTERNOON. HI-RES MODELS
HAVE CONSISTENTLY SHOWN THE THUNDERSTORM ACTIVITY INCREASING IN
COVERAGE AND MOVING EAST LATER THIS AFTERNOON AS A WEAK UPPER LEVEL
SHORTWAVE EJECTS OUT OF THE CENTRAL ROCKIES. THE BEST CHANCES
THROUGH THE EVENING WILL GENERALLY BE CONFINED TO THE PANHANDLE AND
SOUTHWEST NEBRASKA. AS FAR AS STORM INTENSITY...MLCAPE IN THE
VICINITY OF THE SFC TROUGH WILL NEAR 1000 J/KG BY LATER AFTERNOON
AND EARLY EVENING. STEEP MID LEVEL LAPSE RATES OF 7-8 C/KM ARE ALSO
IN PLACE OVER THE HIGH PLAINS. A STORM OR TWO REACHING STRONG TO
SEVERE LIMITS WITH HAIL AND GUSTY WINDS CANNOT BE RULED OUT...MAINLY
WEST OF HWY 61. THE ABILITY FOR STORMS TO SUSTAIN THEMSELVES AND
REMAIN ORGANIZED IS IN QUESTION DUE RATHER WEAK MID LEVEL FLOW AND
DEEP LAYER SHEAR ONLY AROUND 25 TO 30 KTS. THE MORE FAVORABLE
ENVIRONMENT WILL REMAIN TO THE SOUTH WHERE FASTER FLOW ALOFT AND
BETTER SHEAR PROFILES RESIDE.
THUNDERSTORM CHANCES MOVE EAST OVERNIGHT BUT COVERAGE SHOULD REMAIN
SCATTERED. UPPER LEVEL LOW CURRENTLY OVER THE DESERT SOUTHWEST WILL
EJECT EASTWARD TOWARD THE CENTRAL PLAINS. THIS WILL KEEP SOUTHERLY
FLOW IN PLACE OVERNIGHT...AND EVENTUALLY THE REDEVELOPMENT OF
STRATUS CLOUDS OVER MUCH OF THE AREA. PATCHY FOG IS POSSIBLE OVER
CENTRAL NEB...BUT BUFKIT DATA CONTINUES TO SUPPORT THICK LOW STRATUS
IN OUR ZONES. THIS IS ALSO SUPPORTED BY VISBY FIELDS IN RECENT RUNS
OF THE HRRR AND NAM. CONFIDENCE NOT HIGH ENOUGH TO INCLUDE ANY FOG
IN THE GRIDS AT THIS POINT...BUT THE EVENING SHIFT WILL NEED TO
REEVALUATE.
MODELS PAINT QPF ACROSS MUCH OF THE CWA BY FRIDAY AFTERNOON...BUT
REMAIN ALL OVER THE PLACE IN REGARDS TO THEIR PLACEMENT. EXPECTING
SCATTERED AND DISORGANIZED SHOWERS AND THUNDERSTORMS DUE TO LACK OF
A FOCUS FOR DEVELOPMENT. NOT EXPECTING MUCH IN THE WAY OF SEVERE
WEATHER AS THE MUCH BETTER ENVIRONMENT WILL BE OFF TO OUR SOUTH AND
EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU APR 23 2015
LONG WAVE TROUGH WILL BE MOVING INLAND FROM THE WEST COAST
FRIDAY NIGHT...WITH A LEAD SHORTWAVE MOVING ACROSS THE CENTRAL PLAINS
AHEAD OF THE TROUGH FRIDAY NIGHT. OPERATIONAL MODELS FCST THE
CENTRAL PLAINS TROUGH TO BECOME CLOSED NEAR OR JUST WEST OF THE MID
MISSOURI VALLEY. THIS WILL BE A RATHER DISORGANIZED EVENT...AND
WITH ONLY WEAK MOISTURE TRANSPORT...LIFT WILL ALSO BE SOMEWHAT
LIMITED AND UNFOCUSED. THIS CONTINUES TO SUGGEST A SHOWERY AND
UNORGANIZED PRECIPITATION EVENT. WILL LIMIT HIGHEST POPS TO 40 TO
50 PERCENT EVENING AND 20 TO 30 PERCENT AFTER MIDNIGHT. BEST
INSTABILITY ACROSS SERN ZONES...WITH HIGHER TSTM CHANCES WITH ONLY
ISOLATED EXPECTED ACROSS THE NORTH/NORTHWEST.
THE MAIN UPPER TROUGH WILL DIG SOUTHEAST ACROSS THE GREAT BASIN ON
SATURDAY AS A TRANSITORY RIDGE MOVES INTO THE CNTRL PLAINS. THIS
WILL LESSEN POPS TO ONLY A SLIGHT CHANCE NORTH AND WEST WITH PARTLY
SUNNY SKIES AND HIGH TEMPS NEAR 60 NORTHEAST TO NEAR 70 FAR
SOUTHWEST. THE GFS ENSEMBLE...GFS...AND ECMWF ALL AGREE THAT THE
UPPER TROUGH WILL DEEPEN INTO THE FOUR CORNERS REGION SATURDAY
NIGHT WITH AN AMPLIFIED SRLY FLOW ALOFT ACROSS THE CNTRL HIGH
PLAINS. CHCS FOR SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE
HIGHS PLAINS WITH CHC POPS WEST OF HWY 83...AND NO WX ACROSS THE
EAST. ANY SHOWERS THAT DEVELOP WILL MOVE NORTH WILL LITTLE OR NOW
EASTWARD PROGRESSION. MEDIUM RANGE MODELS THEN INDICATED CLOSED
LOW WILL TRACK EAST ACROSS NEW MEXICO...THE TEXAS PANHANDLE...AND
THEN ACROSS NORTHERN TEXAS AND SOUTHERN OKLAHOMA SUNDAY THROUGH
MONDAY NIGHT. THERE REMAINS ENOUGH MODEL AGREEMENT AND CONFIDENCE
TO KEEP POPS INTO THE LIKELY CATEGORY ACROSS THE EASTERN PANHANDLE
SUNDAY WITH CHC POPS EAST TO VALENTINE THROUGH BROKEN BOW. AS NRN
STREAM TROUGH APPROACHES SUNDAY NIGHT AND MONDAY...POPS LESSEN AND
REMAIN ONLY ACROSS THE WEST. DRY MONDAY NIGHT AND BEYOND. UPPER
RIDGE OVER THE GREAT BASIN WILL SLOWLY BUILD EAST INTO THE CENTRAL
CONUS THROUGH THURSDAY. THE COOLEST DAY LOOK TO BE SUNDAY AS
EASTERLY UPSLOPE WINDS AND CLOUDINESS/SHOWERS LIMITS HIGHS TO
LOWER MID 50S WEST TO NEAR 60 EAST. HIGHS THEN WARM INTO THE 60S
MONDAY/TUESDAY...LOW 70S WEDNESDAY...THEN MID/UPPER 70S THURSDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 619 PM CDT THU APR 23 2015
ISOLATED THUNDERSTORMS ARE POSSIBLE IN PORTIONS OF WESTERN AND
SOUTHWESTERN NEBRASKA THIS EVENING. GIVEN THE EXPECTED ISOLATED
NATURE OF STORMS...WILL HANDLE THE MENTION IN THE 00Z TAFS WITH A
VCTS GROUP THIS EVENING. FOR THE KLBF TERMINAL...LOW CLOUDINESS
WILL MOVE INTO THE TERMINAL AFTER 06Z TONIGHT WITH CIGS RANGING
FROM 700 TO 1000 FT AGL. CIGS WILL CLIMB TO MVFR AFTER MID MORNING
FRIDAY WITH BROKEN HIGH CLOUDS EXPECTED FRIDAY AFTERNOON. FOR THE
KVTN TERMINAL...SOME MVFR CIGS ARE POSSIBLE LATE TONIGHT AND
FRIDAY MORNING AT THE KVTN TERMINAL WITH CIGS AROUND 1500 FT AGL.
VFR CIGS ARE EXPECTED FRIDAY AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MARTIN
SHORT TERM...MARTIN
LONG TERM...ROBERG
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1227 PM CDT WED APR 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT WED APR 22 2015
ELONGATED HIGH PRESSURE FROM CANADA TO THE
MISSOURI BASIN DRIFTS EAST TODAY SETTING UP A COOL SOUTHERLY RETURN
FLOW FROM KANSAS. THE RAP MODEL INDICATES A WARM FRONT WILL DEVELOP
ACROSS WRN NEB WHICH MOVES EAST THIS AFTERNOON AND TONIGHT. THE
MODEL SUGGESTS A NARROW MIDLEVEL CLOUD SHIELD WILL DEVELOP NEAR
VALENTINE TONIGHT WHICH IS WELL SUPPORTED BY THE GFS...LESS SO BY
THE OTHER MODELS. THE OBVIOUS CULPRIT IS 700MB FRONTOGENESIS AND THE
DEVELOPING WARM FRONT. THE FORECAST IS FOR PARTLY CLOUDY SKIES TODAY
AND TONIGHT WITH TEMPERATURES RISING INTO THE 50S AND 60S. LOWS
TONIGHT FALL INTO THE 30S TO NEAR FREEZING EAST OF HIGHWAY 83.
MOISTURE WILL RETURN LATE TONIGHT ACROSS SWRN NEB. THE MODEL
SOUNDINGS SUGGESTS A SUNRISE SURPRISE THURSDAY MORNING WITH STRATUS
DEVELOPING WITH THE ONSET OF MIXING AFTER SUNRISE. A SLIGHT DELAY
OF 3 HOURS IN THE MOISTURE RETURN WOULD RESULT IN SUFFICIENT
HEATING AND MIXING TO PRECLUDE CLOUD DEVELOPMENT. MEANWHILE...IF
THE MODELS ARE TOO SLOW THEN CLOUDS COULD FORM BEFORE SUNRISE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 348 AM CDT WED APR 22 2015
LONG WAVE TROUGH WILL BE MOVING ONSHORE THE WEST COAST
THURSDAY...WITH FLOW ALOFT BECOMING SOUTHWEST AHEAD OF THE TROUGH
ACROSS THE CENTRAL PLAINS. ONE DISTURBANCE WILL EJECT NORTHEAST FROM
THE TROUGH THURSDAY NIGHT INTO FRIDAY. MODELS ARE WEAKER WITH THIS
FEATURE COMPARED TO A COUPLE OF DAYS AGO...AND HAVE PUT THE BREAKS
ON THE POPS. WILL LEAVE IN THE CHANCE CATEGORY FOR THE MOST PART.
LIFT IS MARGINAL AND NOT ORGANIZED IN ANY ONE AREA...SO THINKING A
MORE SHOWERY TYPE RAIN WILL OCCUR. ACTUALLY KIND OF HARD TO PIN DOWN
EXACTLY WHERE...BUT THE BETTER CHANCE WOULD LIKELY BE AFTER MIDNIGHT
THURSDAY NIGHT INTO FRIDAY MORNING ON THE NOSE OF A SOUTHERLY LOW
LEVEL JET ACROSS CENTRAL INTO EASTERN NEBRASKA. THEN LATER IN THE
DAY ACROSS THE WESTERN HIGH PLAINS OF NEBRASKA INTO EASTERN
COLORADO...AS CONDITIONS BECOME SOMEWHAT UNSTABLE LEADING TO A
SCATTERING OF THUNDERSTORMS. THESE STORMS WILL BE AIDED BY THE
ACTUAL DISTURBANCE CROSSING THE AREA DURING PEAK HEATING. THESE
STORMS WILL WEAKEN SOMEWHAT AS THEY MOVE EAST...BUT DO EXPECT AT
LEAST SHOWERS TO MOVE ACROSS THE AREA FRIDAY NIGHT. AGAIN...DOESN/T
APPEAR TO BE REAL ORGANIZED...AND CAN/T JUSTIFY LIKELY POPS AT ANY
ONE LOCATION AT THIS TIME.
FOR THE WEEKEND INTO EARLY NEXT WEEK...IT LOOKS RATHER INTERESTING.
THE LONG WAVE TROUGH MOVES INTO THE ROCKIES BY SUNDAY. SATURDAY
LOOKING TO BE A FAIRLY DRY DAY AS RIDGING DEVELOPS ACROSS THE
CENTRAL PLAINS AHEAD OF THE TROUGH. TRIED TO LIMIT POPS TO JUST A
SLIGHT CHANCE FOR THIS REASON SATURDAY. BY SUNDAY NIGHT INTO
MONDAY...THE MODELS DIG THE TROUGH INTO THE FOUR CORNERS WHERE IT
SHOULD CLOSE OFF. VERY GOOD AGREEMENT AMONG THE GFS ENSEMBLE
MEMBERS ON THIS OCCURRING...AND BOTH THE OPERATIONAL GFS AND ECMWF
INDICATE THIS SCENARIO AS WELL. HOWEVER...THE ECMWF CONTINUES TO
DIG THE SYSTEM SOUTH INTO TEXAS LEAVING US WITH LITTLE
PRECIPITATION. THE GFS AND GFS ENSEMBLE MEAN ON THE OTHER HAND ARE
FARTHER NORTH...AND HAVE A CLOSED H700MB LOW CENTER IN SOUTHEAST
COLORADO SUNDAY NIGHT. ALSO THEY HAVE HEAVY RAINFALL SUNDAY NIGHT
INTO MONDAY FROM NORTHWEST KANSAS...NORTH AND WEST ACROSS
NORTHEAST COLORADO...SOUTHWEST NEBRASKA AND THE SOUTHERN NEBRASKA
PANHANDLE. OVERALL THIS STRONG CLOSED SYSTEM IS A NEW DEVELOPMENT
IN THE MODELS/ENSEMBLE TONIGHT...AND WON/T GET CARRIED AWAY WITH
RAIN CHANCES JUST YET. ALSO TONIGHT/S SOLUTIONS ARE A BIT
SLOWER...SO THE HIGHER CHANCES FOR RAIN CURRENTLY IN THE FORECAST
FOR SUNDAY MAY HAVE TO BE EXTENDED INTO SUNDAY NIGHT AND MONDAY.
WILL CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1221 PM CDT WED APR 22 2015
VFR CONDITIONS ARE FORECAST FOR MOST OF WESTERN AND NORTH CENTRAL
NEBRASKA THROUGH THE NEXT 24 HOURS. PRIMARY FORECAST CONCERN IS
THE CHANCE FOR LOW CIGS IN SOUTHWEST NEBRASKA THURSDAY MORNING.
MODEL GUIDANCE REMAINS INCONSISTENT WITH THE HANDLING OF
POTENTIAL CLOUD COVER TOMORROW MORNING...HOWEVER AT THIS TIME THE
BEST CHANCE FOR MVFR OR LOWER CIGS LOOKS TO BE JUST WEST AND
SOUTH OF KLBF.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
619 AM CDT WED APR 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT WED APR 22 2015
ELONGATED HIGH PRESSURE FROM CANADA TO THE
MISSOURI BASIN DRIFTS EAST TODAY SETTING UP A COOL SOUTHERLY RETURN
FLOW FROM KANSAS. THE RAP MODEL INDICATES A WARM FRONT WILL DEVELOP
ACROSS WRN NEB WHICH MOVES EAST THIS AFTERNOON AND TONIGHT. THE
MODEL SUGGESTS A NARROW MIDLEVEL CLOUD SHIELD WILL DEVELOP NEAR
VALENTINE TONIGHT WHICH IS WELL SUPPORTED BY THE GFS...LESS SO BY
THE OTHER MODELS. THE OBVIOUS CULPRIT IS 700MB FRONTOGENESIS AND THE
DEVELOPING WARM FRONT. THE FORECAST IS FOR PARTLY CLOUDY SKIES TODAY
AND TONIGHT WITH TEMPERATURES RISING INTO THE 50S AND 60S. LOWS
TONIGHT FALL INTO THE 30S TO NEAR FREEZING EAST OF HIGHWAY 83.
MOISTURE WILL RETURN LATE TONIGHT ACROSS SWRN NEB. THE MODEL
SOUNDINGS SUGGESTS A SUNRISE SURPRISE THURSDAY MORNING WITH STRATUS
DEVELOPING WITH THE ONSET OF MIXING AFTER SUNRISE. A SLIGHT DELAY
OF 3 HOURS IN THE MOISTURE RETURN WOULD RESULT IN SUFFICIENT
HEATING AND MIXING TO PRECLUDE CLOUD DEVELOPMENT. MEANWHILE...IF
THE MODELS ARE TOO SLOW THEN CLOUDS COULD FORM BEFORE SUNRISE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 348 AM CDT WED APR 22 2015
LONG WAVE TROUGH WILL BE MOVING ONSHORE THE WEST COAST
THURSDAY...WITH FLOW ALOFT BECOMING SOUTHWEST AHEAD OF THE TROUGH
ACROSS THE CENTRAL PLAINS. ONE DISTURBANCE WILL EJECT NORTHEAST FROM
THE TROUGH THURSDAY NIGHT INTO FRIDAY. MODELS ARE WEAKER WITH THIS
FEATURE COMPARED TO A COUPLE OF DAYS AGO...AND HAVE PUT THE BREAKS
ON THE POPS. WILL LEAVE IN THE CHANCE CATEGORY FOR THE MOST PART.
LIFT IS MARGINAL AND NOT ORGANIZED IN ANY ONE AREA...SO THINKING A
MORE SHOWERY TYPE RAIN WILL OCCUR. ACTUALLY KIND OF HARD TO PIN DOWN
EXACTLY WHERE...BUT THE BETTER CHANCE WOULD LIKELY BE AFTER MIDNIGHT
THURSDAY NIGHT INTO FRIDAY MORNING ON THE NOSE OF A SOUTHERLY LOW
LEVEL JET ACROSS CENTRAL INTO EASTERN NEBRASKA. THEN LATER IN THE
DAY ACROSS THE WESTERN HIGH PLAINS OF NEBRASKA INTO EASTERN
COLORADO...AS CONDITIONS BECOME SOMEWHAT UNSTABLE LEADING TO A
SCATTERING OF THUNDERSTORMS. THESE STORMS WILL BE AIDED BY THE
ACTUAL DISTURBANCE CROSSING THE AREA DURING PEAK HEATING. THESE
STORMS WILL WEAKEN SOMEWHAT AS THEY MOVE EAST...BUT DO EXPECT AT
LEAST SHOWERS TO MOVE ACROSS THE AREA FRIDAY NIGHT. AGAIN...DOESN/T
APPEAR TO BE REAL ORGANIZED...AND CAN/T JUSTIFY LIKELY POPS AT ANY
ONE LOCATION AT THIS TIME.
FOR THE WEEKEND INTO EARLY NEXT WEEK...IT LOOKS RATHER INTERESTING.
THE LONG WAVE TROUGH MOVES INTO THE ROCKIES BY SUNDAY. SATURDAY
LOOKING TO BE A FAIRLY DRY DAY AS RIDGING DEVELOPS ACROSS THE
CENTRAL PLAINS AHEAD OF THE TROUGH. TRIED TO LIMIT POPS TO JUST A
SLIGHT CHANCE FOR THIS REASON SATURDAY. BY SUNDAY NIGHT INTO
MONDAY...THE MODELS DIG THE TROUGH INTO THE FOUR CORNERS WHERE IT
SHOULD CLOSE OFF. VERY GOOD AGREEMENT AMONG THE GFS ENSEMBLE
MEMBERS ON THIS OCCURRING...AND BOTH THE OPERATIONAL GFS AND ECMWF
INDICATE THIS SCENARIO AS WELL. HOWEVER...THE ECMWF CONTINUES TO
DIG THE SYSTEM SOUTH INTO TEXAS LEAVING US WITH LITTLE
PRECIPITATION. THE GFS AND GFS ENSEMBLE MEAN ON THE OTHER HAND ARE
FARTHER NORTH...AND HAVE A CLOSED H700MB LOW CENTER IN SOUTHEAST
COLORADO SUNDAY NIGHT. ALSO THEY HAVE HEAVY RAINFALL SUNDAY NIGHT
INTO MONDAY FROM NORTHWEST KANSAS...NORTH AND WEST ACROSS
NORTHEAST COLORADO...SOUTHWEST NEBRASKA AND THE SOUTHERN NEBRASKA
PANHANDLE. OVERALL THIS STRONG CLOSED SYSTEM IS A NEW DEVELOPMENT
IN THE MODELS/ENSEMBLE TONIGHT...AND WON/T GET CARRIED AWAY WITH
RAIN CHANCES JUST YET. ALSO TONIGHT/S SOLUTIONS ARE A BIT
SLOWER...SO THE HIGHER CHANCES FOR RAIN CURRENTLY IN THE FORECAST
FOR SUNDAY MAY HAVE TO BE EXTENDED INTO SUNDAY NIGHT AND MONDAY.
WILL CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 614 AM CDT WED APR 22 2015
VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT THROUGH 06Z.
THEREAFTER...THE MODELS SUGGEST MOISTURE ACROSS OKLAHOMA WILL
RETURN NORTH UP THE HIGH PLAINS. THUS THERE IS THE POTENTIAL FOR
MVFR/IFR CIGS TO DEVELOP SOUTH OF INTERSTATE 80 09Z-12Z ASSUMING
THE MODEL TIMING IS CORRECT. IF THE MOISTURE RETURN IS SLOW THESE
LOW CIGS COULD FORM 13Z-15Z OR NOT AT ALL IF THE MOISTURE RETURN
IS EVEN SLOWER.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
402 AM CDT WED APR 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT WED APR 22 2015
ELONGATED HIGH PRESSURE FROM CANADA TO THE
MISSOURI BASIN DRIFTS EAST TODAY SETTING UP A COOL SOUTHERLY RETURN
FLOW FROM KANSAS. THE RAP MODEL INDICATES A WARM FRONT WILL DEVELOP
ACROSS WRN NEB WHICH MOVES EAST THIS AFTERNOON AND TONIGHT. THE
MODEL SUGGESTS A NARROW MIDLEVEL CLOUD SHIELD WILL DEVELOP NEAR
VALENTINE TONIGHT WHICH IS WELL SUPPORTED BY THE GFS...LESS SO BY
THE OTHER MODELS. THE OBVIOUS CULPRIT IS 700MB FRONTOGENESIS AND THE
DEVELOPING WARM FRONT. THE FORECAST IS FOR PARTLY CLOUDY SKIES TODAY
AND TONIGHT WITH TEMPERATURES RISING INTO THE 50S AND 60S. LOWS
TONIGHT FALL INTO THE 30S TO NEAR FREEZING EAST OF HIGHWAY 83.
MOISTURE WILL RETURN LATE TONIGHT ACROSS SWRN NEB. THE MODEL
SOUNDINGS SUGGESTS A SUNRISE SPECIAL THURSDAY MORNING WITH STRATUS
DEVELOPING WITH THE ONSET OF MIXING AFTER SUNRISE. A SLIGHT DELAY OF
3 HOURS IN THE MOISTURE RETURN WOULD RESULT IN SUFFICIENT HEATING
AND MIXING TO PRECLUDE CLOUD DEVELOPMENT. MEANWHILE...IF THE MODELS
ARE TOO SLOW THEN CLOUDS COULD FORM BEFORE SUNRISE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 348 AM CDT WED APR 22 2015
LONG WAVE TROUGH WILL BE MOVING ONSHORE THE WEST COAST
THURSDAY...WITH FLOW ALOFT BECOMING SOUTHWEST AHEAD OF THE TROUGH
ACROSS THE CENTRAL PLAINS. ONE DISTURBANCE WILL EJECT NORTHEAST FROM
THE TROUGH THURSDAY NIGHT INTO FRIDAY. MODELS ARE WEAKER WITH THIS
FEATURE COMPARED TO A COUPLE OF DAYS AGO...AND HAVE PUT THE BREAKS
ON THE POPS. WILL LEAVE IN THE CHANCE CATEGORY FOR THE MOST PART.
LIFT IS MARGINAL AND NOT ORGANIZED IN ANY ONE AREA...SO THINKING A
MORE SHOWERY TYPE RAIN WILL OCCUR. ACTUALLY KIND OF HARD TO PIN DOWN
EXACTLY WHERE...BUT THE BETTER CHANCE WOULD LIKELY BE AFTER MIDNIGHT
THURSDAY NIGHT INTO FRIDAY MORNING ON THE NOSE OF A SOUTHERLY LOW
LEVEL JET ACROSS CENTRAL INTO EASTERN NEBRASKA. THEN LATER IN THE
DAY ACROSS THE WESTERN HIGH PLAINS OF NEBRASKA INTO EASTERN
COLORADO...AS CONDITIONS BECOME SOMEWHAT UNSTABLE LEADING TO A
SCATTERING OF THUNDERSTORMS. THESE STORMS WILL BE AIDED BY THE
ACTUAL DISTURBANCE CROSSING THE AREA DURING PEAK HEATING. THESE
STORMS WILL WEAKEN SOMEWHAT AS THEY MOVE EAST...BUT DO EXPECT AT
LEAST SHOWERS TO MOVE ACROSS THE AREA FRIDAY NIGHT. AGAIN...DOESN/T
APPEAR TO BE REAL ORGANIZED...AND CAN/T JUSTIFY LIKELY POPS AT ANY
ONE LOCATION AT THIS TIME.
FOR THE WEEKEND INTO EARLY NEXT WEEK...IT LOOKS RATHER INTERESTING.
THE LONG WAVE TROUGH MOVES INTO THE ROCKIES BY SUNDAY. SATURDAY
LOOKING TO BE A FAIRLY DRY DAY AS RIDGING DEVELOPS ACROSS THE
CENTRAL PLAINS AHEAD OF THE TROUGH. TRIED TO LIMIT POPS TO JUST A
SLIGHT CHANCE FOR THIS REASON SATURDAY. BY SUNDAY NIGHT INTO
MONDAY...THE MODELS DIG THE TROUGH INTO THE FOUR CORNERS WHERE IT
SHOULD CLOSE OFF. VERY GOOD AGREEMENT AMONG THE GFS ENSEMBLE
MEMBERS ON THIS OCCURRING...AND BOTH THE OPERATIONAL GFS AND ECMWF
INDICATE THIS SCENARIO AS WELL. HOWEVER...THE ECMWF CONTINUES TO
DIG THE SYSTEM SOUTH INTO TEXAS LEAVING US WITH LITTLE
PRECIPITATION. THE GFS AND GFS ENSEMBLE MEAN ON THE OTHER HAND ARE
FARTHER NORTH...AND HAVE A CLOSED H700MB LOW CENTER IN SOUTHEAST
COLORADO SUNDAY NIGHT. ALSO THEY HAVE HEAVY RAINFALL SUNDAY NIGHT
INTO MONDAY FROM NORTHWEST KANSAS...NORTH AND WEST ACROSS
NORTHEAST COLORADO...SOUTHWEST NEBRASKA AND THE SOUTHERN NEBRASKA
PANHANDLE. OVERALL THIS STRONG CLOSED SYSTEM IS A NEW DEVELOPMENT
IN THE MODELS/ENSEMBLE TONIGHT...AND WON/T GET CARRIED AWAY WITH
RAIN CHANCES JUST YET. ALSO TONIGHT/S SOLUTIONS ARE A BIT
SLOWER...SO THE HIGHER CHANCES FOR RAIN CURRENTLY IN THE FORECAST
FOR SUNDAY MAY HAVE TO BE EXTENDED INTO SUNDAY NIGHT AND MONDAY.
WILL CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1146 PM CDT TUE APR 21 2015
EXPECT CLEAR SKIES ACROSS WESTERN AND NORTH CENTRAL NEBRASKA OVER
THE NEXT 24 HOURS. THE EXCEPTION WILL BE AT THE KLBF TERMINAL
DURING THE AFTERNOON HOURS ON WEDNESDAY AS SOME SCATTERED CLOUDS
AROUND 10000 FT AGL ARE POSSIBLE. WINDS WILL BECOME SOUTHERLY WEDS
MORNING AND INCREASE TO 10 TO 15 KTS DURING THE AFTERNOON HOURS.
WINDS WILL BECOME EASTERLY WEDS EVENING AND DIMINISH TO UNDER 10
KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
830 PM PDT THU APR 23 2015
.SYNOPSIS...A SERIES OF UPPER LEVEL DISTURBANCES WILL KEEP
RELATIVELY COOL WEATHER WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS IN THE FORECAST THROUGH SATURDAY NIGHT. AREAS OF GUSTY
SOUTHWEST WINDS ARE EXPECTED THROUGH SATURDAY WITH GUSTY NORTH WINDS
DEVELOPING SATURDAY NIGHT AND SUNDAY. HIGH PRESSURE WILL BUILD IN BY
EARLY NEXT WEEK LEADING TO DRY CONDITIONS AND A WARMING TREND.
&&
.UPDATE...SCATTERED SHOWER AND THUNDERSTORM ACTIVITY IS WINDING DOWN
THIS EVENING WITH NO NEW LIGHTNING STRIKES IN OUR FORECAST AREA IN
THE PAST HOUR. RADAR AND SATELLITE TRENDS PAINT A PICTURE OF DRYING
AND STABILIZING CONDITIONS AND I HAVE GONE AHEAD AND UPDATED THE
GRIDS TO STRIP DOWN POPS ACROSS MUCH OF THE FORECAST AREA AND REDUCE
SKY COVER. STILL MAINTAINED SOME SLIGHT CHANCES ACROSS OUR SOUTHERN
GREAT BASIN ZONES WHERE THE HRRR MODEL INSISTS ON SOME LINGERING
SHOWER ACTIVITY OVERNIGHT BUT OTHERWISE THINGS ARE QUICKLY SETTLING
DOWN.
-OUTLER-
&&
.SHORT TERM...THROUGH SATURDAY NIGHT.
BASICALLY RANDOM CONVECTION DEVELOPED ABOUT AS EXPECTED TODAY
UNDERNEATH THE UPPER LOW OVER THE AREA. A FEW STORMS HAVE ACTUALLY
GENERATED WETTING RAIN BUT THOSE HAVE BEEN SPOTTY. THIS ACTIVITY
WILL CONTINUE THROUGH THE EARLY EVENING BEFORE DECREASE TO JUST A
SLIGHT CHANCE OF SHOWERS OVERNIGHT AS THE LOW/TROUGH MOVES EAST OF
THE AREA. THE NEXT SHORTWAVE WILL MOVE ACROSS THE AREA LATE TONIGHT
THROUGH FRIDAY NIGHT BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS
TO INYO COUNTY IN CALIFORNIA AND JUST ABOUT ALL OF OUR SOUTHERN
NEVADA AND NORTHWEST ARIZONA AREA. THE BEST PRECIPITATION CHANCES
WILL BE ACROSS THE SOUTHERN GREAT BASIN...CLOSE TO THE MAINLY TROUGH
ENERGY. NORTHERN LINCOLN COUNTY MAY ACTUALLY GET A DECENT AMOUNT OF
RAINFALL WITH THIS SYSTEM FRIDAY AFTERNOON AND EVENING. THE FINAL
AND POSSIBLY STRONGEST TROUGH IN THE SERIES WILL DROP ACROSS NEVADA
INTO ARIZONA SATURDAY AND SATURDAY NIGHT BRINGING CONTINUE
PRECIPITATION CHANCES ACROSS MUCH OF THE AREA EXCEPT PERHAPS SAN
BERNARDINO COUNTY. WE WILL PROBABLY SEE PRETTY GOOD FRONTOGENESIS
WITH THIS SYSTEM...RESULTING IN ANOTHER ROUND OF DECENT
PRECIPITATION OVER LINCOLN COUNTY SATURDAY AFTERNOON. THIS BAND MAY
EVEN PRODUCE DECENT PRECIPITATION ACROSS PORTIONS OF MOHAVE COUNTY
SATURDAY NIGHT WHILE THE WESTERN PART OF THE FORECAST AREA STARTS TO
CLEAR OUT.
WINDS WILL BE A FACTOR IN SOME AREAS THE NEXT COUPLE OF DAY. BREEZY
SOUTHWEST WINDS WILL DEVELOP ACROSS THE MOJAVE DESERT FRIDAY WITH HI-
RES MODELS AND MOS GUIDANCE INDICATING ADVISORY LEVEL WINDS IN THE
WESTERN MOJAVE DESERT OF SAN BERNARDINO COUNTY. THE SAME GUIDANCE
INDICATES EVEN STRONGER WINDS SATURDAY THERE WITH MOS SHOWING
POTENTIAL FOR HIGH WIND CRITERIA BEING REACHED. THIS MAY BE A BIT
OVERDONE HOWEVER. FOR NOW I DECIDED TO GO WITH A WIND ADVISORY FOR
THAT ZONE BEGINNING 11 AM FRIDAY AND RUNNING THROUGH 11 PM SATURDAY.
THERE MAY BE A BIT OF A LULL FRIDAY NIGHT BUT TO KEEP THINGS FROM
GETTING CONFUSING I JUST RAN THE ADVISORY FOR THE WHOLE TIME. GUSTY
NORTH/NORTHWEST WINDS WILL BEGIN TO DEVELOP BEHIND A COLD FRONT
SATURDAY NIGHT AND THERE IS POTENTIAL FOR ADVISORY LEVEL GUSTS IN
PLACES. TEMPERATURE WILL BE A BIT ON THE COOL SIDE DURING THE SHORT
TERM DUE TO THESE UPPER LEVEL DISTURBANCES...CLOUD COVER AND
SHOWERS IN THE AREA.
.LONG TERM...SUNDAY MORNING THROUGH THURSDAY.
DEEP TROUGH WILL BE LOCATED JUST EAST OF THE NEVADA/UTAH BORDER WITH
GUSTY NORTH WINDS EXPECTED ACROSS THE ENTIRE AREA SUNDAY. MOST AREAS
WILL LIKELY SEE WINDS IN THE 20-30 MPH RANGE...BUT LOCATIONS DOWN
THE COLORADO RIVER WILL LIKELY BE HIGHER AND WIND ADVISORIES/LAKE
WIND ADVISORIES MAY BE NEEDED. MUCH OF THE PRECIPITATION IS EXPECTED
TO BE EAST OF THE AREA BY SUNDAY MORNING...BUT A FEW ISOLATED
SHOWERS MAY STILL BE POSSIBLE ALONG THE UTAH BORDER ALONG WITH THE
THE FAR EASTERN AREAS OF MOHAVE COUNTY. BY SUNDAY AFTERNOON THE
TROUGH IS EXPECTED TO BE FAR ENOUGH EAST THAT ANY PRECIPITATION WILL
BE EAST OF THE AREA. ALTHOUGH ITS EXPECTED TO BE DRY AREAWIDE MONDAY
WE WILL STILL HAVE ENOUGH INFLUENCE FROM THE LOW TO KEEP GUSTY NORTH
TO NORTHEAST WINDS OVER THE AREA...ESPECIALLY DOWN THE RIVER. HIGH
PRESSURE WILL BUILD OVER THE AREA TUESDAY THROUGH THURSDAY LEADING
TO WARMING TEMPERATURES AND MUCH LIGHTER WINDS. TEMPERATURES ON
SUNDAY ARE STILL EXPECTED TO BE A FEW DEGREES BELOW NORMAL...BUT ARE
EXPECTED TO CLIMB TO AROUND NORMAL MONDAY. TEMPERATURES ON TUESDAY
ARE FORECAST TO JUMP SEVERAL DEGREES AND MAY BE CLOSE TO 10-15
DEGREES ABOVE NORMAL BY FRIDAY. &&
.AVIATION...FOR MCCARRAN...WINDS ARE EXPECTED TO BE MAINLY FROM THE
SOUTH AROUND 10 KNOTS THROUGH FRIDAY MORNING...INCREASING TO AROUND
15 KNOTS WITH GUSTS TO 25-30 KNOTS FRIDAY AFTERNOON.
HOWEVER...ISOLATED SHOWERS AND THUNDERSTORMS THROUGH THIS EVENING
WILL LIKELY CAUSE ERRATIC WINDS AT TIME. CLOUD BASES WITH THESE
SHOWERS WILL MAINLY BE IN THE 9-10KFT RANGE. MORE SHOWERS COULD
DEVELOP IN THE AREA AGAIN FRIDAY AFTERNOON.
.FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...UNSETTLED WEATHER CONDITIONS EXPECTED WITH SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED. LOCALLY STRONG UPDRAFTS
AND CONVECTIVE TURBULENCE POSSIBLE NEAR SHOWER ACTIVITY AS WELL AS
GUSTY AND ERRATIC SURFACE WINDS. CLOUD BASES EXPECTED TO BE IN THE 7
TO 10K FT RANGE. SHOWERS AND THUNDERSTORMS WILL GRADUALLY DIMINISH
IN THE LATE EVENING HOURS THOUGH A FEW STRAY SHOWERS MAY PERSIST
INTO THE NIGHT. MORE SHOWERS AND THUNDERSTORMS WILL DEVELOP AGAIN
FRIDAY AFTERNOON EXCEPT IN SAN BERNARDINO COUNTY. WINDS MAINLY SOUTH-
SOUTHWEST 10-15 KNOTS WITH GUSTS TO 25 KNOTS THROUGH FRIDAY MORNING.
WIND SPEEDS WILL INCREASE TO 15-25 KNOTS WITH GUSTS 30 TO 35 KNOTS
FRIDAY AFTERNOON. GUSTS TO 40 KNOTS ARE POSSIBLE IN WESTERN SAN
BERNARDINO COUNTY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS SHOULD REPORT ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
SHORT TERM/AVIATION...HARRISON
LONG TERM...GORELOW
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
823 PM EDT THU APR 23 2015
.SYNOPSIS...
A LARGE STORM SYSTEM WILL SLIDE NORTHEASTWARD OVERNIGHT THROUGH
FRIDAY, KEEPING TEMPERATURES WELL BELOW NORMAL. SNOW SHOWER AND
FLURRY ACTIVITY WILL DIMINISH AS DRIER AIR MOVES IN LATE TONIGHT
AND FRIDAY, WITH IMPROVING CONDITIONS FOR SATURDAY WITH SUNSHINE
EXPECTED.
&&
.NEAR TERM /THROUGH FRIDAY/...
WATER VAPOR IMAGERY SHOWS A LARGE UPPER LEVEL CYCLONE OVER
NORTHERN NEW ENGLAND AND SOUTHERN QUEBEC THIS EVENING WHICH
CONTINUES TO LEAD TO A COLD AND MOIST NORTHWEST FLOW OF AIR ACROSS
CENTRAL NY AND NORTHEAST PA. 850 MB TEMPERATURES WERE VERY CHILLY
FOR THIS TIME OF YEAR RUNNING AROUND -8C TO -10C AT THIS TIME.
HRRR, RAP. WRF NMM, WRF ARW AND NAM12 ALL SHOW 850 MB TEMPS
DROPPING TO -11C OR SO BY 12Z. LAKE ONTARIO AND ERIE WATER
TEMPERATURES WERE ARND +1 TO 3C LEADING TO SOME LAKE ENHANCEMENT
OF THE SYNOPTIC SCALE MOISTURE THAT WAS WRAPPING ARND THE UPPER
LEVEL LOW. THIS WILL CONTINUE TO LEAD TO LATE SEASON SNOW SHOWERS
AND FLURRIES OVERNIGHT.
ONE SHORT WAVE WAS PASSING EAST OF OUR REGION AT THIS TIME SO THE
RADAR COVERAGE OF THE SNOW SHOWERS AND FLURRIES HAS DIMINISHED AT
THIS TIME. THE RAP SHOWS ANOTHER SHRT WAVE WILL PASS BY ARND 5-6Z
WHICH SHUD RAMP SN SHOWER ACVTY UP A BIT...ESPECIALLY IN NC NY
WHERE THERE WILL BE MORE LAKE MOISTURE ON A W-NW LL FLOW PATTERN.
THE REST OF THE FORECAST AREA WILL REMAIN UNDER A STRATOCUMULUS
DECK THROUGH THE NIGHT WITH A FEW FLURRIES AT TIMES.
FOR FRIDAY...THE STRG LATE APRIL SUN WILL EVENTUALLY BREAK UP THE
LAKE ENHANCED MOISTURE AND CLOUDS AND WE SHUD SEE SOME BREAKS BY
AFTERNOON. OUR WRN AND SRN PARTS OF OUR FORECAST AREA LIKELY WILL
BREAK OUT AND BECOME PC TO MS BY AFTERNOON. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH SUB FREEZING TEMPERATURE MOST AREAS
OVERNIGHT. THERE IS TOO MUCH WIND AND CLOUDS FOR ANY FROST AND
OUR GROWING SEASON HAS NOT BEGUN YET SO NO MENTION OF FROST IN OUR
ZONES FOR OVERNIGHT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
STACKED CYCLONE DRIFTS FROM MAINE TO OFF THE ATLANTIC COAST THIS
PERIOD. AFTER WIDELY SCATTERED RAIN/SNOW SHOWER ACTIVITY DURING
THE MORNING HOURS, ESPECIALLY OVER NERN FA, DRY NORTHWESTERLY
FLOW SHOULD YIELD FAIR WEATHER FOR FRIDAY AFTERNOON AND SATURDAY.
AFTER MAXES IN THE UPPER 30S TO MIDDLE 40S ON FRIDAY, BL-850MB
TEMPS WILL REBOUND SEVERAL DEGREES CELSIUS FOR SATURDAY. GIVEN DRY
ATMOSPHERE AND GOOD AMOUNT OF SUN, THINK MAX TEMPS WILL BOUNCE
BACK INTO THE LOWER 50S IN MOST SPOTS, THOUGH THIS WILL STILL BE
8 TO 12 DEGREES BELOW NORMAL MAX TEMPS.
A SURFACE LOW PRESSURE CENTER WILL SLIDE EASTWARD THROUGH VA/NC ON
SUNDAY, WHILE A COOL RIDGE BUILDS SOUTH THROUGH THE GREAT LAKES
INTO THE OHIO VALLEY. BELIEVE THE PRECIPITATION WILL REMAIN SOUTH
AND WEST OF OUR FA, THOUGH A WEAK WAVE IN THE UPPER FLOW MAY
SPAWN A SPRINKLE OR LIGHT SHOWER UP THE LAKE PLAIN.
330 AM EDT UPDATE...
THE STACKED UPPR LOW WILL MOVE AS FAR EAST AS MAINE AND WE WILL
REMAIN UNDER A NW FLOW ALOFT ON FRIDAY. THE CHANCE FOR SHOWERS
WILL CONTINUE THRU FRIDAY AS WE WILL REMAIN WITHIN THE WRAP AROUND
MOISTURE. THE CHANCE FOR SHOWERS ON SAT WILL BECOME LESS AS THE
MOISTURE WITH THIS SYSTEM SHIFT SLIGHTLY FURTHER EAST AND THE LOW
SHIFTS SLIGHTLY FURTHER EAST OFF THE EAST COAST. PRECIP TYPE WILL
BE DEPENDENT ON SFC TEMPS... THUS SNOW POSSIBLE DURING THE
OVERNIGHT HOURS AND RAIN DURING THE DAY TIME.
NW FLOW ALOFT WILL REMAIN OVER THE REGION THRU THE FORECAST PERIOD
AND CONTINUE TO SUPPORT COLDER THAN NORMAL TEMPS ACROSS THE
REGION. TEMPS ON SAT WILL SLIGHTLY REBOUND INTO THE LOW TO UPPR
40S. AS THE UPPR LOW SHIFT EAST ON SAT... TEMPS WILL BE ABLE TO
RISE INTO THE LOWER 50S OVER MUCH OF THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BOTH THE GFS AND EURO SHOW A DEEP AND VERTICALLY STACKED LOW
WOBBLING OFF THE NE CST ON MON. NLY FLOW BHD THE FLOW WITH THE LWR
UPR HGTS WILL KEEP ISLTD TO SCT SHOWRS OVER THE FCST AREA...ESP
OVER THE NY ZONES...WITH BLO NRML DAYTIME TEMPS.
IRONICALLY...THE EURO IS MORE PROGRESSIVE WITH THE SYSTEM AND
SHOWS SOME IMPRVMT LTR TUE INTO THU WITH WEAK SFC RDGG AND A
NARROW RDG ALOFT. GFS WANTS TO KEEP THE UPR LOW HANGING ARND AND
IN FACT CAPTURES A SRN STREAM SYSTEM LATE IN THE PD TO ENHANCE
THE UPR TROF.
MODELS HAVE BEEN INCONSISTENT WITH THE FCST IN THE LONG TERM LDG
TO A LOW CONFIDENCE FCST...NOT ALL THAT UNUSUAL THIS TIME OF YEAR.
SO...CONTD WITH THE HPC GUID IDEA OF LOW CHANCE OR SLGT CHANCE
POPS FOR MUCH OF THE LONG TERM...ESP IN THE NRN AND ERN ZONES.
WITH THE NLY FLOW...TEMPS WILL REMAIN BLO NRML...ESP DURING THE
DAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
MAINLY VFR CONDITIONS UNDER A STRATOCUMULUS DECK WILL PREVAIL FOR
THE OVERNIGHT HOURS. BRIEF PERIOD OF IFR EXPECTED UNTIL 1Z AT KRME
OTHERWISE WE SHUD SEE ONLY OCCASIONAL MVFR IN CIG AND SNSH
OVERNIGHT AT KRME AND ALSO KITH...KBGM.
FOR FRIDAY BKN-OVC STRATOCUMULUS DECK WILL BREAK UP INTO SCT-BKN
CUMULUS CLOUDS BY AFTERNOON ALL TAFS WITH VFR CONDITIONS
PREVAILING.
WINDS WILL BE NORTHWEST 10 TO 15 KNOTS TONIGHT AND 15-20 KNOTS
WITH GUSTS 25 TO 30 KNOTS ON FRIDAY.
.OUTLOOK...
FRI NGT...OCNL MVFR RESTRICTIONS FROM -SHSN.
SAT-SUN...MAINLY VFR.
MON - TUE...OCNL -SHRA WITH BRIEF MVFR RESTRICTIONS...MAINLY NY
TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP/DJN
NEAR TERM...DJN
SHORT TERM...DJP
LONG TERM...DGM
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
400 PM EDT WED APR 22 2015
.SYNOPSIS...
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE FROM NORTH OF
THE GREAT LAKES EASTWARD ACROSS ONTARIO AND QUEBEC THIS WEEK. THIS
FEATURE WILL KEEP NORTHERN NEW YORK AND VERMONT TRAPPED IN AN
OVERCAST SHOWERY PERIOD. SOME SNOW SHOWERS ARE POSSIBLE ACROSS THE
HIGHER TERRAIN...WITH SOME ACCUMULATING SNOW FOR THE SUMMITS.
&&
.NEAR TERM /UNTIL 8 AM THURSDAY MORNING/...
AS OF 345 PM EDT WEDNESDAY...NORTH COUNTRY WILL REMAIN IN DEEP-
LAYER SOUTHWESTERLY FLOW THIS EVENING AS CLOSED UPPER LOW BEGINS
TO SLOWLY DRIFT EASTWARD. SHORTWAVE CURRENTLY LIFTING
NORTHEASTWARD ACROSS OUR VERMONT ZONES...THIS WILL ENHANCE UPWARD
MOTION AND EXPAND COVERAGE OF SHOWER ACTIVITY THIS EVENING. EXPECT
WIDESPREAD RAIN ACROSS OUR VERMONT ZONES AND HAVE CATEGORICAL POPS
FOR THIS REASON. LINGERING RAIN SHOWERS THIS EVENING WILL
GRADUALLY MOVE NEWD OUT OF THE REGION OVERNIGHT...ENDING BY
MIDNIGHT. WHILE SKIES WILL REMAIN MOSTLY CLOUDY OVERNIGHT...LOW-
LEVEL CAA FROM THE WEST WILL ALLOW TEMPS TO FALL INTO THE LOW-MID
30S.
&&
.SHORT TERM /8 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 345 PM EDT WEDNESDAY...SEASONABLY COOL AND MOIST
CONDITIONS...WITH POTENTIAL FOR UPSLOPE/OROGRAPHIC SNOWFALL
THURSDAY NIGHT INTO FRIDAY...INCLUDING LIGHT TO MODERATE
ACCUMULATIONS FOR THE HIGHER SUMMITS.
DURING THE DAYTIME HOURS ON THURSDAY UPPER LEVEL LOW WILL BE ITS
CLOSEST IN PROXIMITY TO OUR FORECAST AREA. CLOUDY SKIES...COOL
TEMPERATURES AND MOIST CONDITIONS WILL CONTINUE. COOLER THAN
NORMAL TEMPERATURES CAN BE EXPECTED. POTENTIAL FOR SHOWERS
INCREASES WITH NORTHWESTERLY FLOW DEVELOPING IN THE AFTERNOON AND
OVERNIGHT. PRETTY GOOD UPSLOPE SNOW SET UP FOR THURSDAY NIGHT AND
COLD ENOUGH ABOVE 1000 FEET FOR SNOW...RAIN SNOW MIX IN THE VALLEY
LOCATIONS. BELOW NORMAL MINIMUM TEMPERATURES ARE EXPECTED WITH
MOST OF THE AREA BOTTOMING OUT AROUND FREEZING. REGION REMAINS
STUCK UNDER INFLUENCE OF UPPER LEVEL LOW ALL THE WAY THROUGH
FRIDAY NIGHT...LOW WILL BE REACHING THE GULF OF MAINE BY FRIDAY
NIGHT. GENERALLY ISOLATED VALLEY SHOWERS AND MORE FREQUENT RAIN
AND SNOW SHOWERS ACROSS THE HIGHER ELEVATIONS ON FRIDAY AND FRIDAY
NIGHT. BELOW NORMAL TEMPERATURES CONTINUE THROUGH THIS PERIOD.
COULD SEE SOME DECENT SNOW ACCUMULATIONS IN THE HIGHER ELEVATIONS
FOR LATE MAY THIS WEEK...BEST CHANCE FOR ACCUMULATIONS BEING
THURSDAY NIGHT INTO FRIDAY MORNING WITH THE STRONGEST
NORTHWESTERLY FLOW DURING THAT TIME AND OROGRAPHIC UPSLOPE EFFECTS
HELPING US OUT. AROUND 6 INCHES OF SNOW ALONG THE RIDGE TOPS FROM
JAY PEAK TO MOUNT MANSFIELD...AND SIMILARLY ACROSS THE HIGHEST
PEAKS OF THE ADIRONDACKS. A COATING TO 1 ONE AMOUNTS DOWN TO ABOUT
1000 FEET WITH NO SIGNIFICANT ACCUMULATIONS BELOW THAT. DURING THE
DAYTIME HOURS ON FRIDAY THE SNOW LEVEL SHOULD LIFT TO 2000 FEET OR
HIGHER.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 326 PM EDT WEDNESDAY...THE BEGINNING OF THE WEEKEND WILL
CONTINUE THE THEME OF PERIODIC APRIL SHOWERS WITH MOSTLY CLOUDY
SKIES UNDER PERSISTENT NORTHWEST UPSLOPE FLOW WITH A CLOSED UPPER
LEVEL LOW TO THE NORTHEAST.
BOTH THE GFS AND ECMWF MODEL INDICATE THE UPPER LEVEL LOW WILL BE
CENTERED JUST OFF THE COAST OF MAINE SATURDAY WITH A SURFACE LOW
PRESSURE SYSTEM LOCATED WELL OFFSHORE SOUTHWEST OF NOVA SCOTIA.
THE PERSISTENT NORTHWEST FLOW WILL GENERATE SOME OFF AND ON
UPSLOPE RAIN/SNOW SHOWERS WITH THE SNOW SHOWERS ONLY REALLY BEING
POSSIBLE IN THE HIGHER SUMMITS DURING THE DAYTIMES WITH A MIX OF
RAIN AND SNOW IN THE VALLEYS POSSIBLE IN THE OVERNIGHT HOURS.
BEGINNING NEXT WEEK THE UPPER LEVEL LOW CONTINUES TO STAY IN A
SEMI PERMANENT LOCATION CENTERED OVER NEW ENGLAND AND THEN A
SURFACE LOW PRESSURE SYSTEM WILL SLIDE OFFSHORE JUST SOUTH OF
VIRGINIA AND PHASE WITH THE RETROGRADING LOW FROM THE CANADIAN
MARITIMES. HOWEVER THE STRENGTH AND INTENSITY OF THAT LOW IS
SIGNIFICANTLY BETWEEN THE GFS AND ECMWF. THE ECMWF REMAINS THE
SLOWER MOVING MODEL FROM THE REST OF THE MODEL SUITE BEING FAR
MORE PROGRESSIVE AND ENDS UP DEVELOPING A 962MB LOW OFFSHORE.
GIVEN THE NATURE OF THE SINGLE OUTLIER I STAYED AWAY FROM THAT
SOLUTION AND RELIED MORE ON A BLEND OF THE CANADIAN AND GFS.
REGARDING TEMPERATURES, DAYTIME MAX TEMPS WILL SEE A SLIGHT
WARMING TREND THROUGH THE WEEKEND INTO NEXT WEEK. EXPECT MAX TEMPS
WILL START IN THE UPPER 40S TO MID 50S ON SUNDAY WARMING TO MID
50S TO LOW 60S BY WEDNESDAY NEXT WEEK. OVERNIGHT LOWS WILL BE
PRETTY CONSISTENTLY IN THE UPPER 20S IN THE HIGHER TERRAIN ABOVE
2000 FEET TO THE MID TO UPPER 30S IN THE SAINT LAWRENCE AND
CHAMPLAIN VALLEYS.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...PERIODS OF MVFR CEILINGS AND VISIBILITIES
DEVELOPING AS RAIN SHOWERS MOVE INTO THE REGION, AND EVEN SOME WET
SNOW FLAKES MIXED IN AT SLK OVERNIGHT AS TEMPS DROP IN THE
BOUNDARY LAYER. SOME OF THE HIRES WINDOWS ARE SHOWING THAT THE
RAIN COULD BE HEAVY AT TIMES IN RUT/MPV HOWEVER GIVEN THE
UNCERTAINTY IN HOW HEAVY THE RAIN WILL FAIL I`VE CONTINUED TO
LEAVE IT OUT OF THE TAFS FOR NOW AND WILL MONITOR/UPDATE AS
NECESSARY.
SCATTERED TO BROKEN VFR CLOUDS AND SCATTERED RAIN SHOWERS WILL
PERSIST ACROSS THE REGION THROUGH TODAY. A WAVE OF LOW PRESSURE
WILL BRING A MORE ORGANIZED PERIOD OF LIGHT RAIN IN THE AFTERNOON
AND EVENING AS DEPICTED IN THE LATEST HRRR WHICH HAS A HANDLE ON
SHOWERS NOW ENTERING THE ST. LAWRENCE VALLEY. THE HRRR SEEMS A BIT
ON THE FASTER SIDE TO MOVE THE SHOWERS OUT SO I INITIALIZED THE
FORECAST WITH THE HRRR BUT THEN TRENDED MORE TOWARDS AN ENSEMBLE
OF THE LOCAL WRF`S FOR THE EVENING WITH REGARDS TO WX/VSBY. WINDS
SOUTH/SOUTHWEST LESS THAN 7 KNOTS BECOMING 10 KNOTS WITH GUSTS
15-20 KNOTS DURING THE DAY TODAY.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY... 18Z THURS - 00Z SAT: VFR
WITH PERSISTENT MOSTLY CLOUDY CONDITIONS AND SOME POSSIBLE MVFR
WITH OFF AND ON LIGHT RAIN. COULD BE A SLIGHT MIX OF RAIN/SNOW
LATE THURS EVENING.
00Z SAT - SUNDAY: VFR WITH PERIODS OF MVFR AS RAIN SHOWERS MOVE
THROUGH THE AREA.
&&
.HYDROLOGY...
FLOOD WARNING CONTINUES FOR THE BARTON RIVER NEAR COVENTRY. MAY
SEE SOME RISES ON OTHER SMALLER RIVERS IN THE REGION WITH
WIDESPREAD RAINFALL ACROSS THE AREA. AT THIS POINT DOES NOT LOOK
LIKE WE WILL NEED ANY FURTHER WARNINGS AT THIS TIME.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NEILES
NEAR TERM...NEILES
SHORT TERM...NEILES
LONG TERM...DEAL
AVIATION...DEAL
HYDROLOGY...NEILES
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
327 PM EDT WED APR 22 2015
.SYNOPSIS...
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES
AND ONTARIO WILL DRIFT SLOWLY EASTWARD THROUGH THE END OF THE
WEEK. THIS SYSTEM WILL PROVIDE THE NORTH COUNTRY WITH SEASONABLY
COOL CONDITIONS...ALONG WITH CONSIDERABLE CLOUDINESS. EMBEDDED
SMALLER SCALE DISTURBANCES WILL BRING PERIODS OF RAIN
SHOWERS...WHICH WILL BE MOST WIDESPREAD LATE TODAY INTO TONIGHT.
SOME SNOW SHOWERS ARE POSSIBLE ACROSS THE HIGHER TERRAIN...WITH
SOME ACCUMULATING SNOW FOR THE SUMMITS ESPECIALLY THURSDAY NIGHT
INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 120 PM EDT WEDNESDAY...GOING FORECAST IS IN REALLY GOOD
SHAPE. AREA OF SHOWERS LIFTING NORTH INTO OUR FORECAST AREA
CURRENTLY. ADJUSTED FORECAST TO REFLECT CURRENT OBSERVATIONS.
PREVIOUS DISCUSSION FOLLOWS.
NORTH COUNTRY WILL REMAIN IN DEEP-LAYER SWLY FLOW TODAY...AS
CLOSED UPPER LOW REMAINS QUASI- STATIONARY NORTH OF THE U.P. OF
MICHIGAN. SHORTWAVE TROUGH ROUNDING THE BASE OF THE 500MB TROUGH
WILL SHIFT NEWD FROM PA ACROSS NY/NEW ENGLAND DURING THE AFTN HRS.
THIS WILL ENHANCE UPWARD MOTION AND EXPAND COVERAGE OF SHOWER
ACTIVITY THIS AFTERNOON AND EVENING. ALL GUIDANCE CONSISTENT IN
SHOWING SHOWER ACTIVITY MOST WIDESPREAD ACROSS CENTRAL/ERN
VT...AND HAVE SHOWN HIGHEST POPS THERE (80-100 PERCENT)...AND
GENERALLY 50-80 PERCENT ACROSS THE CHAMPLAIN VALLEY WWD INTO THE
ADIRONDACKS.
BASED ON EARLY AM RADAR TRENDS...IT APPEARS ISOLD/SCT SHOWERS
WILL MOVE ACROSS NRN NY - AND PERHAPS INTO THE CHAMPLAIN VALLEY -
DURING THE MID MORNING HRS. SHOWERS MOVING GENERALLY NE 30-35 MPH
EAST OF LAKE ONTARIO AS OF 1120Z. HAVE CARRIED CHANCE POPS DURING
THE MORNING HRS TO COVER THIS SHOWER ACTIVITY AS IT MOVES NEWD.
OVERALL TREND WILL BE FOR ACTIVITY TO BECOME MORE WIDESPREAD AS
THE AFTERNOON PROGRESSES, ESPECIALLY FOR CENTRAL AND ERN VT. SUNNY
SKIES EXPECTED AT TIMES DURING THE MORNING HRS...BEFORE TRENDING
MOSTLY CLOUDY FOR THE AFTERNOON AND EVENING PERIOD. RAINFALL AMTS
GENERALLY A TENTH TO 0.30" FROM THE ADIRONDACKS EWD...WITH THE
HIGHEST TOTALS EXPECTED ACROSS ERN VT. MEANWHILE...RAINFALL
GENERALLY <0.10" ACROSS THE ST. LAWRENCE VALLEY. HIGH TEMPERATURES
TODAY GENERALLY EXPECTED IN THE MID-UPR 50S. SFC WINDS GENERALLY
SOUTH 10-15 MPH THIS MORNING...SHIFTING INTO THE SW AND WEST THIS
AFTN WITH TROUGH PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 306 AM EDT WEDNESDAY...THE SHORT-TERM WILL FEATURE
CONTINUED SEASONABLY COOL AND MOIST CONDITIONS...WITH POTENTIAL
FOR UPSLOPE/OROGRAPHIC SNOWFALL THURSDAY NIGHT INTO
FRIDAY...INCLUDING LIGHT TO MODERATE ACCUMULATIONS FOR THE HIGHER
SUMMITS.
LINGERING RAIN SHOWERS ACROSS CENTRAL INTO NERN VT THIS EVENING
WILL GRADUALLY MOVE NEWD OUT OF THE REGION OVERNIGHT. MAY SEE AN
ADDITIONAL 0.10"-0.20" RAINFALL ACROSS CENTRAL/ERN VT BEFORE
ACTIVITY ENDS AROUND MIDNIGHT. SHOULD SEE AT LEAST SOME MODEST
RISES ON AREA RIVERS TONIGHT...AND MINOR FLOODING IS POSSIBLE FOR
THE BARTON RIVER AT COVENTRY BASED ON CURRENT EXPECTATIONS. WHILE
SKIES WILL REMAIN MOSTLY CLOUDY OVERNIGHT...LOW-LEVEL CAA FROM THE
WEST WILL ALLOW TEMPS TO FALL INTO THE LOW-MID 30S FOR OVERNIGHT
LOWS.
UPR LOW CENTER PROGRESSES ACROSS NRN NY AND VT ON
THURSDAY...MAINTAINING CLOUDY SKIES, ALONG WITH COOL AND MOIST
CONDITIONS. HIGH TEMPERATURES ON THURSDAY WILL BE WELL BELOW
SEASONABLE NORMS...AND GENERALLY IN THE MID TO UPPER 40S...AND
LOCALLY IN THE LOWER 40S FOR THE NRN ADIRONDACK REGION.
POTENTIAL FOR SHOWERS WILL GRADUALLY INCREASE AS NWLY FLOW
DEVELOPS ACROSS NRN NY THURSDAY AFTN...AND ACROSS VT THURSDAY
NIGHT. LOOKS LIKE AN UPSLOPE FLOW SETUP FOR A TIME THURSDAY
NIGHT...AND THERMAL FIELDS SUPPORT SNOW AT ELEVATIONS ABOVE
1000`...WITH A RAIN/SNOW MIX POSSIBLE IN VALLEY LOCATIONS LATER
THURSDAY NIGHT. LOWS THURSDAY NIGHT WILL BE NEAR FREEZING MOST
LOCATIONS...AND LOCALLY IN THE LOW- MID 20S ABOVE 2000 FEET
ELEVATION.
CYCLONIC FLOW REMAINS IN PLACE THROUGH FRIDAY...WITH ISOLD VALLEY
SHOWERS AND MORE FREQUENT RAIN/SNOW SHOWERS ACROSS THE HIGHER
ELEVATIONS. HIGHS FRIDAY REMAINING COOL...GENERALLY 45-50F.
MAY SEE SOME DECENT SNOWFALL ACCUMULATIONS ACROSS THE HIGHER
SUMMITS OF THE NRN ADIRONDACKS AND CENTRAL/NRN GREEN MTNS...MAINLY
THURSDAY NIGHT AND FRIDAY. CURRENT INDICATIONS SUPPORT AROUND 6"
OF NEW SNOW ALONG THE RIDGE TOPS FROM JAY PEAK TO MT.
MANSFIELD...AND SIMILARLY ACROSS THE HIGH PEAKS OF THE
ADIRONDACKS. MAY SEE A WET COATING-1" SNOWFALL AMTS DOWN TO ABOUT
1000` DURING THURSDAY NIGHT...WITH SNOW LEVELS RISING DURING THE
DAY FRIDAY TO ABOVE 2000`.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 326 PM EDT WEDNESDAY...THE BEGINNING OF THE WEEKEND WILL
CONTINUE THE THEME OF PERIODIC APRIL SHOWERS WITH MOSTLY CLOUDY
SKIES UNDER PERSISTENT NORTHWEST UPSLOPE FLOW WITH A CLOSED UPPER
LEVEL LOW TO THE NORTHEAST.
BOTH THE GFS AND ECMWF MODEL INDICATE THE UPPER LEVEL LOW WILL BE
CENTERED JUST OFF THE COAST OF MAINE SATURDAY WITH A SURFACE LOW
PRESSURE SYSTEM LOCATED WELL OFFSHORE SOUTHWEST OF NOVA SCOTIA. THE
PERSISTENT NORTHWEST FLOW WILL GENERATE SOME OFF AND ON UPSLOPE
RAIN/SNOW SHOWERS WITH THE SNOW SHOWERS ONLY REALLY BEING POSSIBLE
IN THE HIGHER SUMMITS DURING THE DAYTIMES WITH A MIX OF RAIN AND
SNOW IN THE VALLEYS POSSIBLE IN THE OVERNIGHT HOURS.
BEGINNING NEXT WEEK THE UPPER LEVEL LOW CONTINUES TO STAY IN A SEMI
PERMANENT LOCATION CENTERED OVER NEW ENGLAND AND THEN A SURFACE LOW
PRESSURE SYSTEM WILL SLIDE OFFSHORE JUST SOUTH OF VIRGINIA AND PHASE
WITH THE RETROGRADING LOW FROM THE CANADIAN MARITIMES. HOWEVER THE
STRENGTH AND INTENSITY OF THAT LOW IS SIGNIFICANTLY BETWEEN THE GFS
AND ECMWF. THE ECMWF REMAINS THE SLOWER MOVING MODEL FROM THE REST
OF THE MODEL SUITE BEING FAR MORE PROGRESSIVE AND ENDS UP DEVELOPING
A 962MB LOW OFFSHORE. GIVEN THE NATURE OF THE SINGLE OUTLIER I
STAYED AWAY FROM THAT SOLUTION AND RELIED MORE ON A BLEND OF THE
CANADIAN AND GFS.
REGARDING TEMPERATURES, DAYTIME MAX TEMPS WILL SEE A SLIGHT WARMING
TREND THROUGH THE WEEKEND INTO NEXT WEEK. EXPECT MAX TEMPS WILL
START IN THE UPPER 40S TO MID 50S ON SUNDAY WARMING TO MID 50S TO
LOW 60S BY WEDNESDAY NEXT WEEK. OVERNIGHT LOWS WILL BE PRETTY
CONSISTENTLY IN THE UPPER 20S IN THE HIGHER TERRAIN ABOVE 2000 FEET
TO THE MID TO UPPER 30S IN THE SAINT LAWRENCE AND CHAMPLAIN VALLEYS.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...PERIODS OF MVFR CEILINGS AND VISIBILITIES
DEVELOPING AS RAIN SHOWERS MOVE INTO THE REGION, AND EVEN SOME
WET SNOW FLAKES MIXED IN AT SLK OVERNIGHT AS TEMPS DROP IN THE
BOUNDARY LAYER. SOME OF THE HIRES WINDOWS ARE SHOWING THAT THE
RAIN COULD BE HEAVY AT TIMES IN RUT/MPV HOWEVER GIVEN THE
UNCERTAINTY IN HOW HEAVY THE RAIN WILL FAIL I`VE CONTINUED TO
LEAVE IT OUT OF THE TAFS FOR NOW AND WILL MONITOR/UPDATE AS
NECESSARY.
SCATTERED TO BROKEN VFR CLOUDS AND SCATTERED RAIN SHOWERS WILL
PERSIST ACROSS THE REGION THROUGH TODAY. A WAVE OF LOW PRESSURE
WILL BRING A MORE ORGANIZED PERIOD OF LIGHT RAIN IN THE AFTERNOON
AND EVENING AS DEPICTED IN THE LATEST HRRR WHICH HAS A HANDLE ON
SHOWERS NOW ENTERING THE ST. LAWRENCE VALLEY. THE HRRR SEEMS A BIT
ON THE FASTER SIDE TO MOVE THE SHOWERS OUT SO I INITIALIZED THE
FORECAST WITH THE HRRR BUT THEN TRENDED MORE TOWARDS AN ENSEMBLE
OF THE LOCAL WRF`S FOR THE EVENING WITH REGARDS TO WX/VSBY. WINDS
SOUTH/SOUTHWEST LESS THAN 7 KNOTS BECOMING 10 KNOTS WITH GUSTS
15-20 KNOTS DURING THE DAY TODAY.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
18Z THURS - 00Z SAT: VFR WITH PERSISTENT MOSTLY CLOUDY CONDITIONS
AND SOME POSSIBLE MVFR WITH OFF AND ON LIGHT RAIN. COULD BE A
SLIGHT MIX OF RAIN/SNOW LATE THURS EVENING.
00Z SAT - SUNDAY: VFR WITH PERIODS OF MVFR AS RAIN SHOWERS MOVE
THROUGH THE AREA.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF UP TO 0.50" ARE EXPECTED ACROSS CENTRAL/ERN
VT THIS AFTERNOON THROUGH THE FIRST HALF OF TONIGHT. SOME MODEST
RIVER RISES CAN BE EXPECTED LATE TODAY THROUGH TONIGHT. SINCE THE
BARTON RIVER AT COVENTRY HAD AN OBSERVED STAGE OF 7.6` AT 07Z THIS
MORNING...ANTICIPATE THAT ONE FORECAST POINT WILL LIKELY REACH
MINOR FLOOD STAGE (BETWEEN 8-9`) SOMETIME TONIGHT.
ELSEWHERE...RIVER RISES ARE EXPECTED TO BE WITHIN BANKFULL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...DEAL
AVIATION...DEAL
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
151 PM EDT WED APR 22 2015
.SYNOPSIS...
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES
AND ONTARIO WILL DRIFT SLOWLY EASTWARD THROUGH THE END OF THE
WEEK. THIS SYSTEM WILL PROVIDE THE NORTH COUNTRY WITH SEASONABLY
COOL CONDITIONS...ALONG WITH CONSIDERABLE CLOUDINESS. EMBEDDED
SMALLER SCALE DISTURBANCES WILL BRING PERIODS OF RAIN
SHOWERS...WHICH WILL BE MOST WIDESPREAD LATE TODAY INTO TONIGHT.
SOME SNOW SHOWERS ARE POSSIBLE ACROSS THE HIGHER TERRAIN...WITH
SOME ACCUMULATING SNOW FOR THE SUMMITS ESPECIALLY THURSDAY NIGHT
INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 120 PM EDT WEDNESDAY...GOING FORECAST IS IN REALLY GOOD
SHAPE. AREA OF SHOWERS LIFTING NORTH INTO OUR FORECAST AREA
CURRENTLY. ADJUSTED FORECAST TO REFLECT CURRENT OBSERVATIONS.
PREVIOUS DISCUSSION FOLLOWS.
NORTH COUNTRY WILL REMAIN IN DEEP-LAYER SWLY FLOW TODAY...AS
CLOSED UPPER LOW REMAINS QUASI- STATIONARY NORTH OF THE U.P. OF
MICHIGAN. SHORTWAVE TROUGH ROUNDING THE BASE OF THE 500MB TROUGH
WILL SHIFT NEWD FROM PA ACROSS NY/NEW ENGLAND DURING THE AFTN HRS.
THIS WILL ENHANCE UPWARD MOTION AND EXPAND COVERAGE OF SHOWER
ACTIVITY THIS AFTERNOON AND EVENING. ALL GUIDANCE CONSISTENT IN
SHOWING SHOWER ACTIVITY MOST WIDESPREAD ACROSS CENTRAL/ERN
VT...AND HAVE SHOWN HIGHEST POPS THERE (80-100 PERCENT)...AND
GENERALLY 50-80 PERCENT ACROSS THE CHAMPLAIN VALLEY WWD INTO THE
ADIRONDACKS.
BASED ON EARLY AM RADAR TRENDS...IT APPEARS ISOLD/SCT SHOWERS
WILL MOVE ACROSS NRN NY - AND PERHAPS INTO THE CHAMPLAIN VALLEY -
DURING THE MID MORNING HRS. SHOWERS MOVING GENERALLY NE 30-35 MPH
EAST OF LAKE ONTARIO AS OF 1120Z. HAVE CARRIED CHANCE POPS DURING
THE MORNING HRS TO COVER THIS SHOWER ACTIVITY AS IT MOVES NEWD.
OVERALL TREND WILL BE FOR ACTIVITY TO BECOME MORE WIDESPREAD AS
THE AFTERNOON PROGRESSES, ESPECIALLY FOR CENTRAL AND ERN VT. SUNNY
SKIES EXPECTED AT TIMES DURING THE MORNING HRS...BEFORE TRENDING
MOSTLY CLOUDY FOR THE AFTERNOON AND EVENING PERIOD. RAINFALL AMTS
GENERALLY A TENTH TO 0.30" FROM THE ADIRONDACKS EWD...WITH THE
HIGHEST TOTALS EXPECTED ACROSS ERN VT. MEANWHILE...RAINFALL
GENERALLY <0.10" ACROSS THE ST. LAWRENCE VALLEY. HIGH TEMPERATURES
TODAY GENERALLY EXPECTED IN THE MID-UPR 50S. SFC WINDS GENERALLY
SOUTH 10-15 MPH THIS MORNING...SHIFTING INTO THE SW AND WEST THIS
AFTN WITH TROUGH PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 306 AM EDT WEDNESDAY...THE SHORT-TERM WILL FEATURE
CONTINUED SEASONABLY COOL AND MOIST CONDITIONS...WITH POTENTIAL
FOR UPSLOPE/OROGRAPHIC SNOWFALL THURSDAY NIGHT INTO
FRIDAY...INCLUDING LIGHT TO MODERATE ACCUMULATIONS FOR THE HIGHER
SUMMITS.
LINGERING RAIN SHOWERS ACROSS CENTRAL INTO NERN VT THIS EVENING
WILL GRADUALLY MOVE NEWD OUT OF THE REGION OVERNIGHT. MAY SEE AN
ADDITIONAL 0.10"-0.20" RAINFALL ACROSS CENTRAL/ERN VT BEFORE
ACTIVITY ENDS AROUND MIDNIGHT. SHOULD SEE AT LEAST SOME MODEST
RISES ON AREA RIVERS TONIGHT...AND MINOR FLOODING IS POSSIBLE FOR
THE BARTON RIVER AT COVENTRY BASED ON CURRENT EXPECTATIONS. WHILE
SKIES WILL REMAIN MOSTLY CLOUDY OVERNIGHT...LOW-LEVEL CAA FROM THE
WEST WILL ALLOW TEMPS TO FALL INTO THE LOW-MID 30S FOR OVERNIGHT
LOWS.
UPR LOW CENTER PROGRESSES ACROSS NRN NY AND VT ON
THURSDAY...MAINTAINING CLOUDY SKIES, ALONG WITH COOL AND MOIST
CONDITIONS. HIGH TEMPERATURES ON THURSDAY WILL BE WELL BELOW
SEASONABLE NORMS...AND GENERALLY IN THE MID TO UPPER 40S...AND
LOCALLY IN THE LOWER 40S FOR THE NRN ADIRONDACK REGION.
POTENTIAL FOR SHOWERS WILL GRADUALLY INCREASE AS NWLY FLOW
DEVELOPS ACROSS NRN NY THURSDAY AFTN...AND ACROSS VT THURSDAY
NIGHT. LOOKS LIKE AN UPSLOPE FLOW SETUP FOR A TIME THURSDAY
NIGHT...AND THERMAL FIELDS SUPPORT SNOW AT ELEVATIONS ABOVE
1000`...WITH A RAIN/SNOW MIX POSSIBLE IN VALLEY LOCATIONS LATER
THURSDAY NIGHT. LOWS THURSDAY NIGHT WILL BE NEAR FREEZING MOST
LOCATIONS...AND LOCALLY IN THE LOW- MID 20S ABOVE 2000 FEET
ELEVATION.
CYCLONIC FLOW REMAINS IN PLACE THROUGH FRIDAY...WITH ISOLD VALLEY
SHOWERS AND MORE FREQUENT RAIN/SNOW SHOWERS ACROSS THE HIGHER
ELEVATIONS. HIGHS FRIDAY REMAINING COOL...GENERALLY 45-50F.
MAY SEE SOME DECENT SNOWFALL ACCUMULATIONS ACROSS THE HIGHER
SUMMITS OF THE NRN ADIRONDACKS AND CENTRAL/NRN GREEN MTNS...MAINLY
THURSDAY NIGHT AND FRIDAY. CURRENT INDICATIONS SUPPORT AROUND 6"
OF NEW SNOW ALONG THE RIDGE TOPS FROM JAY PEAK TO MT.
MANSFIELD...AND SIMILARLY ACROSS THE HIGH PEAKS OF THE
ADIRONDACKS. MAY SEE A WET COATING-1" SNOWFALL AMTS DOWN TO ABOUT
1000` DURING THURSDAY NIGHT...WITH SNOW LEVELS RISING DURING THE
DAY FRIDAY TO ABOVE 2000`.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 352 AM EDT WEDNESDAY...CONTINUING THE THEME OF PERIODIC
APRIL SHOWERS WITH MOSTLY CLOUDY AND COOL WEATHER FROM CYCLONIC
NORTHWEST UPSLOPE FLOW AROUND A CLOSED UPPER LOW TO OUR NORTH AND
EAST.
MODEL CONSENSUS IS THAT THE LOW WILL INITIALLY BE OVER NORTHERN
MAINE FRIDAY NIGHT AND IT GRADUALLY FILLS AND MOVES SLOWLY EAST
INTO THE CANADIAN MARITIMES BY THE END OF THE PERIOD ON TUESDAY
WHICH WILL LESSEN THE CHANCE OF SHOWERS AS THE DAYS GO ON. STILL A
CHANCE OF SNOW SHOWERS ON THE UPPER PORTIONS OF THE MOUNTAINS BY
DAY WITH FREEZING LEVELS LOWERING OVERNIGHT POSSIBLY REACHING THE
VALLEY LOCATIONS WITH A MIX OF RAIN AND SNOW SHOWERS EARLY MORNING
HOURS.
MODELS CONTINUE TO BE IN DECENT AGREEMENT WITH THE LOCATION OF
THE UPPER LOW THROUGH SUNDAY THEN DIVERGE ON THE PLACEMENT MONDAY
AND TUESDAY. ECWMF A BIT OF AN OUTLIER COMPARED TO THE GFS, GEFS,
NAEFS, UK, AND CANADIAN MODELS WHICH ARE A BIT MORE PROGRESSIVE VS
THE ECMWF WHICH ACTUALLY SHOWS THE LOW RETROGRADING BACK OVER NEW
ENGLAND BY MONDAY NIGHT AND TUESDAY.
DAYTIME MAX TEMPERATURES WILL BE IN THE UPPER 40S TO MID 50S
THROUGHOUT THE LONG TERM WITH LOWS IN THE UPPER 20S TO MID 30S
WITH A SLIGHT UPWARD TREND NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...PERIODS OF MVFR CEILINGS AND VISIBILITIES
DEVELOPING AS RAIN SHOWERS MOVE INTO THE REGION, AND EVEN SOME
WET SNOW FLAKES MIXED IN AT SLK OVERNIGHT AS TEMPS DROP IN THE
BOUNDARY LAYER. SOME OF THE HIRES WINDOWS ARE SHOWING THAT THE
RAIN COULD BE HEAVY AT TIMES IN RUT/MPV HOWEVER GIVEN THE
UNCERTAINTY IN HOW HEAVY THE RAIN WILL FAIL I`VE CONTINUED TO
LEAVE IT OUT OF THE TAFS FOR NOW AND WILL MONITOR/UPDATE AS
NECESSARY.
SCATTERED TO BROKEN VFR CLOUDS AND SCATTERED RAIN SHOWERS WILL
PERSIST ACROSS THE REGION THROUGH TODAY. A WAVE OF LOW PRESSURE
WILL BRING A MORE ORGANIZED PERIOD OF LIGHT RAIN IN THE AFTERNOON
AND EVENING AS DEPICTED IN THE LATEST HRRR WHICH HAS A HANDLE ON
SHOWERS NOW ENTERING THE ST. LAWRENCE VALLEY. THE HRRR SEEMS A BIT
ON THE FASTER SIDE TO MOVE THE SHOWERS OUT SO I INITIALIZED THE
FORECAST WITH THE HRRR BUT THEN TRENDED MORE TOWARDS AN ENSEMBLE
OF THE LOCAL WRF`S FOR THE EVENING WITH REGARDS TO WX/VSBY. WINDS
SOUTH/SOUTHWEST LESS THAN 7 KNOTS BECOMING 10 KNOTS WITH GUSTS
15-20 KNOTS DURING THE DAY TODAY.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
18Z THURS - 00Z SAT: VFR WITH PERSISTENT MOSTLY CLOUDY CONDITIONS
AND SOME POSSIBLE MVFR WITH OFF AND ON LIGHT RAIN. COULD BE A
SLIGHT MIX OF RAIN/SNOW LATE THURS EVENING.
00Z SAT - SUNDAY: VFR WITH PERIODS OF MVFR AS RAIN SHOWERS MOVE
THROUGH THE AREA.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF UP TO 0.50" ARE EXPECTED ACROSS CENTRAL/ERN
VT THIS AFTERNOON THROUGH THE FIRST HALF OF TONIGHT. SOME MODEST
RIVER RISES CAN BE EXPECTED LATE TODAY THROUGH TONIGHT. SINCE THE
BARTON RIVER AT COVENTRY HAD AN OBSERVED STAGE OF 7.6` AT 07Z THIS
MORNING...ANTICIPATE THAT ONE FORECAST POINT WILL LIKELY REACH
MINOR FLOOD STAGE (BETWEEN 8-9`) SOMETIME TONIGHT.
ELSEWHERE...RIVER RISES ARE EXPECTED TO BE WITHIN BANKFULL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...SISSON
AVIATION...DEAL/SISSON
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
121 PM EDT WED APR 22 2015
.SYNOPSIS...
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES
AND ONTARIO WILL DRIFT SLOWLY EASTWARD THROUGH THE END OF THE
WEEK. THIS SYSTEM WILL PROVIDE THE NORTH COUNTRY WITH SEASONABLY
COOL CONDITIONS...ALONG WITH CONSIDERABLE CLOUDINESS. EMBEDDED
SMALLER SCALE DISTURBANCES WILL BRING PERIODS OF RAIN
SHOWERS...WHICH WILL BE MOST WIDESPREAD LATE TODAY INTO TONIGHT.
SOME SNOW SHOWERS ARE POSSIBLE ACROSS THE HIGHER TERRAIN...WITH
SOME ACCUMULATING SNOW FOR THE SUMMITS ESPECIALLY THURSDAY NIGHT
INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 120 PM EDT WEDNESDAY...GOING FORECAST IS IN REALLY GOOD
SHAPE. AREA OF SHOWERS LIFTING NORTH INTO OUR FORECAST AREA
CURRENTLY. ADJUSTED FORECAST TO REFLECT CURRENT OBSERVATIONS.
PREVIOUS DISCUSSION FOLLOWS.
NORTH COUNTRY WILL REMAIN IN DEEP-LAYER SWLY FLOW TODAY...AS
CLOSED UPPER LOW REMAINS QUASI- STATIONARY NORTH OF THE U.P. OF
MICHIGAN. SHORTWAVE TROUGH ROUNDING THE BASE OF THE 500MB TROUGH
WILL SHIFT NEWD FROM PA ACROSS NY/NEW ENGLAND DURING THE AFTN HRS.
THIS WILL ENHANCE UPWARD MOTION AND EXPAND COVERAGE OF SHOWER
ACTIVITY THIS AFTERNOON AND EVENING. ALL GUIDANCE CONSISTENT IN
SHOWING SHOWER ACTIVITY MOST WIDESPREAD ACROSS CENTRAL/ERN
VT...AND HAVE SHOWN HIGHEST POPS THERE (80-100 PERCENT)...AND
GENERALLY 50-80 PERCENT ACROSS THE CHAMPLAIN VALLEY WWD INTO THE
ADIRONDACKS.
BASED ON EARLY AM RADAR TRENDS...IT APPEARS ISOLD/SCT SHOWERS
WILL MOVE ACROSS NRN NY - AND PERHAPS INTO THE CHAMPLAIN VALLEY -
DURING THE MID MORNING HRS. SHOWERS MOVING GENERALLY NE 30-35 MPH
EAST OF LAKE ONTARIO AS OF 1120Z. HAVE CARRIED CHANCE POPS DURING
THE MORNING HRS TO COVER THIS SHOWER ACTIVITY AS IT MOVES NEWD.
OVERALL TREND WILL BE FOR ACTIVITY TO BECOME MORE WIDESPREAD AS
THE AFTERNOON PROGRESSES, ESPECIALLY FOR CENTRAL AND ERN VT. SUNNY
SKIES EXPECTED AT TIMES DURING THE MORNING HRS...BEFORE TRENDING
MOSTLY CLOUDY FOR THE AFTERNOON AND EVENING PERIOD. RAINFALL AMTS
GENERALLY A TENTH TO 0.30" FROM THE ADIRONDACKS EWD...WITH THE
HIGHEST TOTALS EXPECTED ACROSS ERN VT. MEANWHILE...RAINFALL
GENERALLY <0.10" ACROSS THE ST. LAWRENCE VALLEY. HIGH TEMPERATURES
TODAY GENERALLY EXPECTED IN THE MID-UPR 50S. SFC WINDS GENERALLY
SOUTH 10-15 MPH THIS MORNING...SHIFTING INTO THE SW AND WEST THIS
AFTN WITH TROUGH PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 306 AM EDT WEDNESDAY...THE SHORT-TERM WILL FEATURE
CONTINUED SEASONABLY COOL AND MOIST CONDITIONS...WITH POTENTIAL
FOR UPSLOPE/OROGRAPHIC SNOWFALL THURSDAY NIGHT INTO
FRIDAY...INCLUDING LIGHT TO MODERATE ACCUMULATIONS FOR THE HIGHER
SUMMITS.
LINGERING RAIN SHOWERS ACROSS CENTRAL INTO NERN VT THIS EVENING
WILL GRADUALLY MOVE NEWD OUT OF THE REGION OVERNIGHT. MAY SEE AN
ADDITIONAL 0.10"-0.20" RAINFALL ACROSS CENTRAL/ERN VT BEFORE
ACTIVITY ENDS AROUND MIDNIGHT. SHOULD SEE AT LEAST SOME MODEST
RISES ON AREA RIVERS TONIGHT...AND MINOR FLOODING IS POSSIBLE FOR
THE BARTON RIVER AT COVENTRY BASED ON CURRENT EXPECTATIONS. WHILE
SKIES WILL REMAIN MOSTLY CLOUDY OVERNIGHT...LOW-LEVEL CAA FROM THE
WEST WILL ALLOW TEMPS TO FALL INTO THE LOW-MID 30S FOR OVERNIGHT
LOWS.
UPR LOW CENTER PROGRESSES ACROSS NRN NY AND VT ON
THURSDAY...MAINTAINING CLOUDY SKIES, ALONG WITH COOL AND MOIST
CONDITIONS. HIGH TEMPERATURES ON THURSDAY WILL BE WELL BELOW
SEASONABLE NORMS...AND GENERALLY IN THE MID TO UPPER 40S...AND
LOCALLY IN THE LOWER 40S FOR THE NRN ADIRONDACK REGION.
POTENTIAL FOR SHOWERS WILL GRADUALLY INCREASE AS NWLY FLOW
DEVELOPS ACROSS NRN NY THURSDAY AFTN...AND ACROSS VT THURSDAY
NIGHT. LOOKS LIKE AN UPSLOPE FLOW SETUP FOR A TIME THURSDAY
NIGHT...AND THERMAL FIELDS SUPPORT SNOW AT ELEVATIONS ABOVE
1000`...WITH A RAIN/SNOW MIX POSSIBLE IN VALLEY LOCATIONS LATER
THURSDAY NIGHT. LOWS THURSDAY NIGHT WILL BE NEAR FREEZING MOST
LOCATIONS...AND LOCALLY IN THE LOW- MID 20S ABOVE 2000 FEET
ELEVATION.
CYCLONIC FLOW REMAINS IN PLACE THROUGH FRIDAY...WITH ISOLD VALLEY
SHOWERS AND MORE FREQUENT RAIN/SNOW SHOWERS ACROSS THE HIGHER
ELEVATIONS. HIGHS FRIDAY REMAINING COOL...GENERALLY 45-50F.
MAY SEE SOME DECENT SNOWFALL ACCUMULATIONS ACROSS THE HIGHER
SUMMITS OF THE NRN ADIRONDACKS AND CENTRAL/NRN GREEN MTNS...MAINLY
THURSDAY NIGHT AND FRIDAY. CURRENT INDICATIONS SUPPORT AROUND 6"
OF NEW SNOW ALONG THE RIDGE TOPS FROM JAY PEAK TO MT.
MANSFIELD...AND SIMILARLY ACROSS THE HIGH PEAKS OF THE
ADIRONDACKS. MAY SEE A WET COATING-1" SNOWFALL AMTS DOWN TO ABOUT
1000` DURING THURSDAY NIGHT...WITH SNOW LEVELS RISING DURING THE
DAY FRIDAY TO ABOVE 2000`.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 352 AM EDT WEDNESDAY...CONTINUING THE THEME OF PERIODIC
APRIL SHOWERS WITH MOSTLY CLOUDY AND COOL WEATHER FROM CYCLONIC
NORTHWEST UPSLOPE FLOW AROUND A CLOSED UPPER LOW TO OUR NORTH AND
EAST.
MODEL CONSENSUS IS THAT THE LOW WILL INITIALLY BE OVER NORTHERN
MAINE FRIDAY NIGHT AND IT GRADUALLY FILLS AND MOVES SLOWLY EAST
INTO THE CANADIAN MARITIMES BY THE END OF THE PERIOD ON TUESDAY
WHICH WILL LESSEN THE CHANCE OF SHOWERS AS THE DAYS GO ON. STILL A
CHANCE OF SNOW SHOWERS ON THE UPPER PORTIONS OF THE MOUNTAINS BY
DAY WITH FREEZING LEVELS LOWERING OVERNIGHT POSSIBLY REACHING THE
VALLEY LOCATIONS WITH A MIX OF RAIN AND SNOW SHOWERS EARLY MORNING
HOURS.
MODELS CONTINUE TO BE IN DECENT AGREEMENT WITH THE LOCATION OF
THE UPPER LOW THROUGH SUNDAY THEN DIVERGE ON THE PLACEMENT MONDAY
AND TUESDAY. ECWMF A BIT OF AN OUTLIER COMPARED TO THE GFS, GEFS,
NAEFS, UK, AND CANADIAN MODELS WHICH ARE A BIT MORE PROGRESSIVE VS
THE ECMWF WHICH ACTUALLY SHOWS THE LOW RETROGRADING BACK OVER NEW
ENGLAND BY MONDAY NIGHT AND TUESDAY.
DAYTIME MAX TEMPERATURES WILL BE IN THE UPPER 40S TO MID 50S
THROUGHOUT THE LONG TERM WITH LOWS IN THE UPPER 20S TO MID 30S
WITH A SLIGHT UPWARD TREND NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 12Z THURSDAY...PERIODS OF MVFR DEVELOPING WITH RAIN AND
MIST DEVELOPING, AND EVEN SOME WET SNOW FLAKES MIXED IN AT KSLK.
POSSIBLE IFR AT RUT/MPV FOR A FEW HOURS THIS AFTERNOON BUT
UNCERTAIN SO LEFT IT OUT FOR NOW.
SCATTERED TO BROKEN VFR CLOUDS AND SCATTERED RAIN SHOWERS WILL
PERSIST ACROSS THE REGION THROUGH TODAY. A WAVE OF LOW PRESSURE
WILL BRING A MORE ORGANIZED PERIOD OF LIGHT RAIN IN THE AFTERNOON
AND EVENING AS DEPICTED IN THE LATEST HRRR WHICH HAS A HANDLE ON
SHOWERS NOW ENTERING THE ST. LAWRENCE VALLEY. WINDS
SOUTH/SOUTHWEST LESS THAN 7 KNOTS BECOMING 10 KNOTS WITH GUSTS
15-20 KNOTS DURING THE DAY TODAY.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY...PERSISTENT MOSTLY CLOUDY
CONDITIONS WITH VFR CEILINGS AS UPPER LOW REMAINS IN PLACE.
PERIODS OF LIGHT RAIN SHOWERS WILL RESULT IN INTERMITTENT MVFR
CEILINGS/VISIBILITIES. ON THURSDAY SOME SNOW POSSIBLY WILL MIX IN
WITH RAIN SHOWERS AT MPV/SLK...AND A MIX OF RAIN/SNOW SHOWERS
POSSIBLE AT ALL TAF LOCATIONS DURING THURSDAY NIGHT AND FRIDAY
NIGHT. OTHERWISE MOSTLY RAIN SHOWERS SATURDAY AND SUNDAY.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF UP TO 0.50" ARE EXPECTED ACROSS CENTRAL/ERN
VT THIS AFTERNOON THROUGH THE FIRST HALF OF TONIGHT. SOME MODEST
RIVER RISES CAN BE EXPECTED LATE TODAY THROUGH TONIGHT. SINCE THE
BARTON RIVER AT COVENTRY HAD AN OBSERVED STAGE OF 7.6` AT 07Z THIS
MORNING...ANTICIPATE THAT ONE FORECAST POINT WILL LIKELY REACH
MINOR FLOOD STAGE (BETWEEN 8-9`) SOMETIME TONIGHT.
ELSEWHERE...RIVER RISES ARE EXPECTED TO BE WITHIN BANKFULL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...SISSON
AVIATION...SISSON
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
736 AM EDT WED APR 22 2015
.SYNOPSIS...
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES AND
ONTARIO WILL DRIFT SLOWLY EASTWARD THROUGH THE END OF THE WEEK. THIS
SYSTEM WILL PROVIDE THE NORTH COUNTRY WITH SEASONABLY COOL
CONDITIONS...ALONG WITH CONSIDERABLE CLOUDINESS. EMBEDDED SMALLER
SCALE DISTURBANCES WILL BRING PERIODS OF RAIN SHOWERS...WHICH WILL
BE MOST WIDESPREAD LATE TODAY INTO TONIGHT. SOME SNOW SHOWERS ARE
POSSIBLE ACROSS THE HIGHER TERRAIN...WITH SOME ACCUMULATING SNOW
FOR THE SUMMITS ESPECIALLY THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 724 AM EDT WEDNESDAY...NORTH COUNTRY WILL REMAIN IN DEEP-
LAYER SWLY FLOW TODAY...AS CLOSED UPPER LOW REMAINS QUASI-
STATIONARY NORTH OF THE U.P. OF MICHIGAN. SHORTWAVE TROUGH
ROUNDING THE BASE OF THE 500MB TROUGH WILL SHIFT NEWD FROM PA
ACROSS NY/NEW ENGLAND DURING THE AFTN HRS. THIS WILL ENHANCE
UPWARD MOTION AND EXPAND COVERAGE OF SHOWER ACTIVITY THIS
AFTERNOON AND EVENING. ALL GUIDANCE CONSISTENT IN SHOWING SHOWER
ACTIVITY MOST WIDESPREAD ACROSS CENTRAL/ERN VT...AND HAVE SHOWN
HIGHEST POPS THERE (80-100 PERCENT)...AND GENERALLY 50-80 PERCENT
ACROSS THE CHAMPLAIN VALLEY WWD INTO THE ADIRONDACKS.
BASED ON EARLY AM RADAR TRENDS...IT APPEARS ISOLD/SCT SHOWERS WILL
MOVE ACROSS NRN NY - AND PERHAPS INTO THE CHAMPLAIN VALLEY -
DURING THE MID MORNING HRS. SHOWERS MOVING GENERALLY NE 30-35
MPH EAST OF LAKE ONTARIO AS OF 1120Z. HAVE CARRIED CHANCE POPS
DURING THE MORNING HRS TO COVER THIS SHOWER ACTIVITY AS IT MOVES
NEWD. OVERALL TREND WILL BE FOR ACTIVITY TO BECOME MORE
WIDESPREAD AS THE AFTERNOON PROGRESSES, ESPECIALLY FOR CENTRAL
AND ERN VT. SUNNY SKIES EXPECTED AT TIMES DURING THE MORNING
HRS...BEFORE TRENDING MOSTLY CLOUDY FOR THE AFTERNOON AND EVENING
PERIOD. RAINFALL AMTS GENERALLY A TENTH TO 0.30" FROM THE
ADIRONDACKS EWD...WITH THE HIGHEST TOTALS EXPECTED ACROSS ERN VT.
MEANWHILE...RAINFALL GENERALLY <0.10" ACROSS THE ST. LAWRENCE
VALLEY. HIGH TEMPERATURES TODAY GENERALLY EXPECTED IN THE MID-UPR
50S. SFC WINDS GENERALLY SOUTH 10-15 MPH THIS MORNING...SHIFTING
INTO THE SW AND WEST THIS AFTN WITH TROUGH PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 306 AM EDT WEDNESDAY...THE SHORT-TERM WILL FEATURE CONTINUED
SEASONABLY COOL AND MOIST CONDITIONS...WITH POTENTIAL FOR
UPSLOPE/OROGRAPHIC SNOWFALL THURSDAY NIGHT INTO FRIDAY...INCLUDING
LIGHT TO MODERATE ACCUMULATIONS FOR THE HIGHER SUMMITS.
LINGERING RAIN SHOWERS ACROSS CENTRAL INTO NERN VT THIS EVENING WILL
GRADUALLY MOVE NEWD OUT OF THE REGION OVERNIGHT. MAY SEE AN
ADDITIONAL 0.10"-0.20" RAINFALL ACROSS CENTRAL/ERN VT BEFORE
ACTIVITY ENDS AROUND MIDNIGHT. SHOULD SEE AT LEAST SOME MODEST RISES
ON AREA RIVERS TONIGHT...AND MINOR FLOODING IS POSSIBLE FOR THE
BARTON RIVER AT COVENTRY BASED ON CURRENT EXPECTATIONS. WHILE SKIES
WILL REMAIN MOSTLY CLOUDY OVERNIGHT...LOW-LEVEL CAA FROM THE WEST
WILL ALLOW TEMPS TO FALL INTO THE LOW-MID 30S FOR OVERNIGHT LOWS.
UPR LOW CENTER PROGRESSES ACROSS NRN NY AND VT ON
THURSDAY...MAINTAINING CLOUDY SKIES, ALONG WITH COOL AND MOIST
CONDITIONS. HIGH TEMPERATURES ON THURSDAY WILL BE WELL BELOW
SEASONABLE NORMS...AND GENERALLY IN THE MID TO UPPER 40S...AND
LOCALLY IN THE LOWER 40S FOR THE NRN ADIRONDACK REGION.
POTENTIAL FOR SHOWERS WILL GRADUALLY INCREASE AS NWLY FLOW DEVELOPS
ACROSS NRN NY THURSDAY AFTN...AND ACROSS VT THURSDAY NIGHT. LOOKS
LIKE AN UPSLOPE FLOW SETUP FOR A TIME THURSDAY NIGHT...AND THERMAL
FIELDS SUPPORT SNOW AT ELEVATIONS ABOVE 1000`...WITH A RAIN/SNOW MIX
POSSIBLE IN VALLEY LOCATIONS LATER THURSDAY NIGHT. LOWS THURSDAY
NIGHT WILL BE NEAR FREEZING MOST LOCATIONS...AND LOCALLY IN THE LOW-
MID 20S ABOVE 2000 FEET ELEVATION.
CYCLONIC FLOW REMAINS IN PLACE THROUGH FRIDAY...WITH ISOLD VALLEY
SHOWERS AND MORE FREQUENT RAIN/SNOW SHOWERS ACROSS THE HIGHER
ELEVATIONS. HIGHS FRIDAY REMAINING COOL...GENERALLY 45-50F.
MAY SEE SOME DECENT SNOWFALL ACCUMULATIONS ACROSS THE HIGHER SUMMITS
OF THE NRN ADIRONDACKS AND CENTRAL/NRN GREEN MTNS...MAINLY THURSDAY
NIGHT AND FRIDAY. CURRENT INDICATIONS SUPPORT AROUND 6" OF NEW SNOW
ALONG THE RIDGE TOPS FROM JAY PEAK TO MT. MANSFIELD...AND SIMILARLY
ACROSS THE HIGH PEAKS OF THE ADIRONDACKS. MAY SEE A WET COATING-1"
SNOWFALL AMTS DOWN TO ABOUT 1000` DURING THURSDAY NIGHT...WITH SNOW
LEVELS RISING DURING THE DAY FRIDAY TO ABOVE 2000`.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 352 AM EDT WEDNESDAY...CONTINUING THE THEME OF PERIODIC
APRIL SHOWERS WITH MOSTLY CLOUDY AND COOL WEATHER FROM CYCLONIC
NORTHWEST UPSLOPE FLOW AROUND A CLOSED UPPER LOW TO OUR NORTH AND
EAST.
MODEL CONSENSUS IS THAT THE LOW WILL INITIALLY BE OVER NORTHERN
MAINE FRIDAY NIGHT AND IT GRADUALLY FILLS AND MOVES SLOWLY EAST
INTO THE CANADIAN MARITIMES BY THE END OF THE PERIOD ON TUESDAY
WHICH WILL LESSEN THE CHANCE OF SHOWERS AS THE DAYS GO ON. STILL A
CHANCE OF SNOW SHOWERS ON THE UPPER PORTIONS OF THE MOUNTAINS BY
DAY WITH FREEZING LEVELS LOWERING OVERNIGHT POSSIBLY REACHING THE
VALLEY LOCATIONS WITH A MIX OF RAIN AND SNOW SHOWERS EARLY MORNING
HOURS.
MODELS CONTINUE TO BE IN DECENT AGREEMENT WITH THE LOCATION OF THE
UPPER LOW THROUGH SUNDAY THEN DIVERGE ON THE PLACEMENT MONDAY AND
TUESDAY. ECWMF A BIT OF AN OUTLIER COMPARED TO THE GFS, GEFS,
NAEFS, UK, AND CANADIAN MODELS WHICH ARE A BIT MORE PROGRESSIVE
VS THE ECMWF WHICH ACTUALLY SHOWS THE LOW RETROGRADING BACK OVER
NEW ENGLAND BY MONDAY NIGHT AND TUESDAY.
DAYTIME MAX TEMPERATURES WILL BE IN THE UPPER 40S TO MID 50S
THROUGHOUT THE LONG TERM WITH LOWS IN THE UPPER 20S TO MID 30S
WITH A SLIGHT UPWARD TREND NEXT WEEK.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...PERIODS OF MVFR DEVELOPING WITH RAIN AND
MIST DEVELOPING, AND EVEN SOME WET SNOW FLAKES MIXED IN AT KSLK.
POSSIBLE IFR AT RUT/MPV FOR A FEW HOURS THIS AFTERNOON BUT
UNCERTAIN SO LEFT IT OUT FOR NOW.
SCATTERED TO BROKEN VFR CLOUDS AND SCATTERED RAIN SHOWERS WILL
PERSIST ACROSS THE REGION THROUGH TODAY. A WAVE OF LOW PRESSURE
WILL BRING A MORE ORGANIZED PERIOD OF LIGHT RAIN IN THE AFTERNOON
AND EVENING AS DEPICTED IN THE LATEST HRRR WHICH HAS A HANDLE ON
SHOWERS NOW ENTERING THE ST. LAWRENCE VALLEY. WINDS
SOUTH/SOUTHWEST LESS THAN 7 KNOTS BECOMING 10 KNOTS WITH GUSTS
15-20 KNOTS DURING THE DAY TODAY.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY...PERSISTENT MOSTLY CLOUDY
CONDITIONS WITH VFR CEILINGS AS UPPER LOW REMAINS IN PLACE.
PERIODS OF LIGHT RAIN SHOWERS WILL RESULT IN INTERMITTENT MVFR
CEILINGS/VISIBILITIES. ON THURSDAY SOME SNOW POSSIBLY WILL MIX IN
WITH RAIN SHOWERS AT MPV/SLK...AND A MIX OF RAIN/SNOW SHOWERS
POSSIBLE AT ALL TAF LOCATIONS DURING THURSDAY NIGHT AND FRIDAY
NIGHT. OTHERWISE MOSTLY RAIN SHOWERS SATURDAY AND SUNDAY.
&&
.HYDROLOGY...
RAINFALL AMOUNTS OF UP TO 0.50" ARE EXPECTED ACROSS CENTRAL/ERN VT
THIS AFTERNOON THROUGH THE FIRST HALF OF TONIGHT. SOME MODEST
RIVER RISES CAN BE EXPECTED LATE TODAY THROUGH TONIGHT. SINCE THE
BARTON RIVER AT COVENTRY HAD AN OBSERVED STAGE OF 7.6` AT 07Z THIS
MORNING...ANTICIPATE THAT ONE FORECAST POINT WILL LIKELY REACH
MINOR FLOOD STAGE (BETWEEN 8-9`) SOMETIME TONIGHT.
ELSEWHERE...RIVER RISES ARE EXPECTED TO BE WITHIN BANKFULL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...SISSON
AVIATION...SISSON
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
943 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 945 PM CDT THU APR 23 2015
NO MAJOR CHANGES WITH THIS UPDATE...BUT WILL INCREASE OVERNIGHT
LOWS A FEW DEGREES WITH CLOUDS AND RETURN FLOW. THERE SHOULD BE A
BAND OF SHOWERS THAT COULD STILL HAVE A RUMBLE OR TWO OF THUNDER
AFTER 6Z INTO SE ND...BUT WILL KEEP IT SHOWERS SINCE INSTABILITY
WEAKENS INTO OUR REGION.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 321 PM CDT THU APR 23 2015
PRECIP CHANCES AND TYPE TONIGHT AND TOMORROW WILL BE THE MAIN
FORECAST ISSUE FOR THE SHORT TERM.
WEST TO SOUTHWEST FLOW CONTINUES OVER THE REGION WITH VARIOUS WEAK
SHORTWAVES MOVING THROUGH THE FLOW. ONE WEAK LEAD SHORTWAVE HAS
ALREADY BEEN HEADING TOWARDS WESTERN ND...WITH SOME DECENT RADAR
RETURNS OVER THAT PART OF THE STATE. SOME LIGHT RAIN HAS BEEN
REACHING THE GROUND...ALTHOUGH NOT AS MUCH AS RADAR WOULD
INDICATE. DEW POINTS OVER THE CWA HAVE BEEN IN THE SINGLE DIGITS
TO TEENS. THE RAP AND HRRR HAVE THE PRECIP DISSIPATING AS IT MOVES
EAST...WHICH SEEMS REASONABLE GIVEN THE VERY DRY AIR. THINK THE
BETTER SHOT FOR PRECIPITATION WILL BE LATER TONIGHT AS A MORE
SOUTHERN SHORTWAVE MOVES INTO WY AND SFC LOW PRESSURE DEVELOPS
OVER WESTERN SD. THERE WILL BE SOME MID LEVEL WARM AIR
ADVECTION/FRONTOGENESIS OVER MAINLY THE SOUTHERN COUNTIES TONIGHT.
SOME OF THE MODELS HAVE SEVERAL TENTHS OF QPF TONIGHT...BUT GIVEN
HOW LONG IT WILL TAKE TO SATURATE WILL LEAN TOWARDS THE LOWER END
FOR PRECIP AMOUNTS. MODEL SOUNDINGS SHOW MOSTLY ABOVE ZERO AS THE
COLUMN SATURATES...BUT SOME SNOW MIXING IN ON THE NORTHERN EDGE OF
THE PRECIP IS NOT OUT OF THE QUESTION.
TOMORROW...THE SHORTWAVE TROUGH MOVES OUT INTO THE PLAINS...AND
THERE SHOULD BE A DECENT AMOUNT OF PRECIP OVER THE SOUTHERN
COUNTIES SPREADING NORTH AND EAST AS THE BEST MID LEVEL BAROCLINIC
ZONE LIFTS ACROSS THE AREA. CONTINUED TO KEEP LIKELY POPS FOR A
RAIN/SNOW MIX OVER THE SOUTHEASTERN COUNTIES FOR FRIDAY
MORNING...LINGERING INTO THE AFTERNOON. THE CLOUDS AND PRECIP
SHOULD KEEP TEMPS IN THE LOWER 40S IN THE EAST...BUT THINK THERE
WILL BE ENOUGH PEAKS OF SUN TO GET ABOVE 50 IN THE WESTERN
COUNTIES WHERE IT WILL BE DRIER. PRECIP WILL BEGIN TO TAPER OFF
FRIDAY NIGHT BUT KEPT SOME LOWER POPS THROUGH SATURDAY MORNING IN
OUR SOUTHEAST TO COORDINATE WITH NEIGHBORS. CLOUDS AND INCREASING
EASTERLY WINDS WILL KEEP TEMPS IN THE 30S FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 321 PM CDT THU APR 23 2015
SATURDAY AND SUNDAY...UPPER RIDGING WILL BUILD IN BRIEFLY...BUT
GIVE WAY AS THE NEXT SPLIT TROUGH BEGINS TO MOVE OUT FROM THE
WESTERN CONUS BY LATE SUNDAY. SFC HIGH PRESSURE OVER ONTARIO
SATURDAY WILL BRING EAST TO SOUTHEASTERLY WINDS WITH DRIER AIR INTO
THE CWA AND HIGHS SHOULD REACH THE 50S WITH AT LEAST SOME BREAKS
IN THE CLOUDS. TEMPS WILL BE EVEN WARMER FOR SUNDAY AS THE SFC
HIGH MOVES OFF TO THE EAST AND A TROUGH DEVELOPING OVER THE
WESTERN PLAINS STARTS SOME WARMER AIR MOVING BACK TO THE NORTH.
THE ECMWF TRIES TO BRING SOME PRECIP INTO OUR WESTERN COUNTIES FOR
SUNDAY AS THE NEXT UPPER SYSTEM APPROACHES...BUT THE OTHER MODELS
ARE A BIT SLOWER. INCLUDED SOME LOW POPS IN THE DEVILS LAKE BASIN
BUT THINK THE MAIN PRECIP WILL HOLD OFF UNTIL AFTER 00Z MONDAY.
SUNDAY NIGHT THROUGH THURSDAY...LONG WAVE UPPER LEVEL LOW PRESSURE
THAT WAS NORTH OF THE GREAT LAKES WILL MOVE OFF THE NEW ENGLAND
STATES EARLY IN THE PERIOD. BUT LONG WAVE TROUGH BECOMES RE-
ESTABLISHED OVER THE NORTHEAST STATES BY THE END OF THE PERIOD.
LONG WAVE UPPER RIDGE BUILDS OVER THE US AND CANADIAN ROCKIES THIS
PERIOD. ECMWF AND GFS WERE TRENDING FASTER THEN SLOWER OVER THE
LAST COUPLE MODEL RUNS. THE GFS IS FASTER THAN THE ECMWF. SO WILL
PREFER THE SLOWER ECMWF.
KEPT POPS FROM PREVIOUS RUN FOR MON NIGHT THROUGH TUE NIGHT.
APPROACHING UPPER LEVEL TROUGH WILL PRODUCE PRECIP FOR MON AND TUE
AND ANOTHER SHORT WAVE TROUGH IS EXPECTED WED NIGHT THROUGH THU
NIGHT.
HIGH TEMPS WERE INCREASED TWO TO FIVE DEGREES FOR MON TUE AND WED.
HIGH TEMPS DECREASED TWO TO FIVE DEGREES FOR THU FROM THIS MORNINGS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 655 PM CDT THU APR 23 2015
VFR CIGS WILL LOWER OVERNIGHT AS SATURATION OCCURS WITH STRONG MID
LEVEL WAA. E/SE WINDS WILL ALSO INCREASE AND GUST OVER 20KT LATER
TONIGHT AND THU MORNING. HAVE MENTIONED A SHOWER NEAR FARGO...AND
KEPT ALL OTHER AREAS DRY THROUGH THE PERIOD. CIGS SHOULD LOWER
INTO THE MVFR RANGE FOR KFAR/KBJI...AND WE WILL HAVE TO MONITOR
THE POTENTIAL FOR OTHER AREAS. THERE IS PLENTY OF DRY AIR IN THE
LOWER LEVELS...SO CIGS COULD REMAIN IN THE VFR RANGE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...JR/HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
939 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 938 PM CDT THU APR 23 2015
TRENDED THE POPS EAST WITH THE RADAR RETURNS. HRRR MODEL CONTINUES
TO DEVELOP SHOWERS OVER THE JAMES RIVER VALLEY IN LOW LEVEL WARM
ADVECTION THROUGH TONIGHT. CLEARING WEST.
UPDATE ISSUED AT 724 PM CDT THU APR 23 2015
UPDATE FOR POPS AND CLOUDS MAINLY. SURFACE LOW PRESSURE IDENTIFIED
BY RUC MODEL CENTERED NEAR THE BLACK HILLS WITH A SOUTHEAST TO
EASTERLY WIND COMPONENT ACROSS ALL OF NORTH DAKOTA. THIS WILL
MAINTAIN FAVORABLE SHEAR AND MAY SUPPORT MAINTAINING THE LIMITED
MOISTURE ACROSS THE JAMES RIVER VALLEY TONIGHT. SHOWERS EXPECTED TO
DEVELOP AND REMAIN IN THE JAMES RIVER VALLEY TONIGHT.
UPDATE ISSUED AT 503 PM CDT THU APR 23 2015
GETTING REPORTS OF SNOW FROM STANLEY AND PARSHALL AREAS. LOOKS
LIKE COOLING TO THE WET BULB IS CREATING ENOUGH COOLING FOR SNOW
LATE THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
SHOWERS THIS AFTERNOON THROUGH TONIGHT HIGHLIGHT THE SHORT TERM
FORECAST.
OUTSIDE OF THE HIGHWAY 200 CORRIDOR...THE MAJORITY OF
PRECIPITATION IS NOT REACHING THE GROUND DUE TO DRY AIR IN THE
SUB-800 MB LAYER. THE 16-18 UTC HRRR ITERATIONS HAVE THE BEST
HANDLING OF THE ONGOING PRECIPITATION...ESPECIALLY THAT WHICH IS
REACHING THE GROUND...AND WILL WEIGH HEAVILY ON THEIR SOLUTIONS
THROUGH AFTERNOON AND EVENING. THEREAFTER...THE 12 AND INCOMING 18
UTC GLOBAL AND HIGH RESOLUTION SUITES ARE IN AGREEMENT ON ELEVATED
SHOWERS DEVELOPING TONIGHT ACROSS THE JAMES AND INTO THE RED RIVER
VALLEYS BY 05 UTC WITH A MODEST LOW LEVEL JET AHEAD OF THE
SURFACE LOW ACROSS WESTERN SOUTH DAKOTA. GIVEN MARGINALLY POSITIVE
SHOWALTER VALUES...WILL NOT PUT IN THUNDER AT THIS TIME. FRIDAY
APPEARS TO BE DRY ACROSS WESTERN AND CENTRAL NORTH DAKOTA BETWEEN
THE STRONGER LOW ACROSS THE CENTRAL PLAINS AND THE PACIFIC
NORTHWEST TROUGH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
A SPLIT FLOW THROUGH THE WEEKEND WITH PERIODS OF INTERACTION
BETWEEN THE SOUTHERN STREAM AND NORTHERN STREAM. THIS WILL
ULTIMATELY SET UP AN INCREASINGLY WET/UNSETTLED WEATHER PATTERN
THROUGH EARLY NEXT WEEK. TWO MAIN SHORTWAVES TO PUSH ACROSS WESTERN
AND CENTRAL NORTH DAKOTA FRIDAY NIGHT THROUGH MONDAY. THE LATEST
ECMWF IS ADVERTISING A MORE CONTINUOUS RAIN OVER THE WEEKEND INTO
MONDAY...WHILE THE GFS/CANADIAN GEM HAS A MORE DISTINCT START/END
TIME WITH EACH WAVE. UTILIZED A BLEND OF THE ABOVE MODELS ABOVE.
EXPECT A BRIEF DRYING AND WARMING TREND BY MIDWEEK...THEN A
PROGRESSIVE AND POSSIBLY UNSETTLED WEATHER PATTERN SETTING UP LATE
IN THE EXTENDED.
FOR FRIDAY NIGHT THROUGH SATURDAY...A TRANSITORY 700MB-500MB RIDGE
DEVELOPS OUT AHEAD OF AN APPROACHING SHORTWAVE TROUGH SLIDING INTO
THE NORTHERN ROCKIES. THIS SHOULD KEEP CONDITIONS DRY FOR MOST AREAS
FRIDAY NIGHT BEFORE EAST TO SOUTHEAST WINDS ADVECT AN AREA OF
MOISTURE INTO THE WEST. THIS MOISTURE WILL CONVERGE INTO AN
APPROACHING SURFACE COLD FRONT IN EASTERN MONTANA. THUS POPS BECOME
LIKELY THEN CATEGORICAL SATURDAY IN THE WEST...WITH DRIER CONDITIONS
IN THE EAST AS MID LEVEL RIDGING REMAINS INTACT UNTIL 00Z SUNDAY.
SATURDAY NIGHT THROUGH MONDAY NIGHT...AS MENTIONED ABOVE THERE ARE
DIFFERENCES IN THE ECMWF AND GFS/GEM...ESPECIALLY SATURDAY NIGHT
THROUGH SUNDAY. PER GFS/GEM...THE SURFACE LOW/COLD FRONT AND SHORTWAVE
MOVE INTO SOUTHERN CANADA WITH SHOWERS DIMINISHING SATURDAY NIGHT
INTO SUNDAY. THE TRAILING COLD FRONT STALLS UNDER A SOUTHWEST FLOW
ALOFT...WITH LOW LEVEL SOUTH TO SOUTHEAST WINDS FEEDING MOISTURE
INTO NORTH DAKOTA. THE GFS/GEM MODELS TREND TOWARD A CESSATION TO
THE PRECIPITATION UNTIL SUNDAY NIGHT WHEN THE THE FRONT BECOMES
RE-ENERGIZED AS THE NEXT SHORTWAVE TROUGH APPROACHES. WITH THE
SURFACE COLD FRONT AND SOUTHERN STREAM MOISTURE ALREADY IN
PLACE...THIS SETS THE STAGE FOR A MORE WIDESPREAD PRECIPITATION
EVENT SUNDAY NIGHT THROUGH MONDAY. AS MENTIONED ABOVE THE LATEST
ECMWF REALLY DOES NOT STOP THE PRECIPITATION WITH THE INITIAL
SHORTWAVE...RATHER KEEPS THE SURGE MAINLY CONTINUOUS IN THE WEST AND
SLOWLY SPREADS IT EAST AND NORTH THROUGH MONDAY. TOTAL PRECIPITATION
AMOUNTS COULD RANGE BETWEEN A HALF INCH TO ONE INCH IN THE WEST TO
AROUND A QUARTER OF AN INCH IN CENTRAL NORTH DAKOTA THROUGH MONDAY NIGHT.
MONDAY NIGHT THROUGH THURSDAY...GOOD AGREEMENT THAT PRECIPITATION
WILL BE EAST OF THE JAMES RIVER VALLEY BY 12Z TUESDAY FOLLOWED BY
UPPER RIDGING TUESDAY AND WEDNESDAY. WARM AIR ADVECTION RAMPS UP
LATE TUESDAY INTO WEDNESDAY...AHEAD OF AN ADVANCING COLD FRONT WHICH
IS FORECAST TO CROSS SOUTHERN CANADA WEDNESDAY AFTERNOON/EVENING. THE GFS
SHOWS SOME LIGHT PRECIPITATION DEVELOPING IN THE NORTH BEHIND THE
FRONT WEDNESDAY AFTERNOON. THE ECMWF IS ABOUT 6HRS SLOWER WITH THE
COLD FRONT...NOT ARRIVING INTO THE NORTHWEST UNTIL AROUND 00Z
THURSDAY. THURSDAY LOOKS DRY...ALTHOUGH THIS MAY BE BRIEF AS
THE NEXT SYSTEM IS ALREADY APPROACHING THURSDAY NIGHT INTO FRIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 724 PM CDT THU APR 23 2015
SURFACE LOW PRESSURE ACROSS WESTERN SOUTH DAKOTA WILL MAINTAIN A
SOUTHEAST TO EASTERLY SURFACE WIND FLOW ACROSS THE STATE. AN UPPER
LEVEL RIPPLE ION THE FLOW ALOFT WILL GENERATE AN AREA OF RAIN
ACROSS SOUTHEAST NORTH DAKOTA TONIGHT. CEILINGS FOR JAMESTOWN
LIKELY TO FALL TO OW VFR ACROSS AFTER 12Z. OTHERWISE VFR ALL
OTHER SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AYD
LONG TERM...KS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
737 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 724 PM CDT THU APR 23 2015
UPDATE FOR POPS AND CLOUDS MAINLY. SURFACE LOW PRESSURE IDENTIFIED
BY RUC MODEL CENTERED NEAR THE BLACK HILLS WITH A SOUTHEAST TO
EASTERLY WIND COMPONENT ACROSS ALL OF NORTH DAKOTA. THIS WILL
MAINTAIN FAVORABLE SHEAR AND MAY SUPPORT MAINTAINING THE LIMITED
MOISTURE ACROSS THE JAMES RIVER VALLEY TONIGHT. SHOWERS EXPECTED TO
DEVELOP AND REMAIN IN THE JAMES RIVER VALLEY TONIGHT.
UPDATE ISSUED AT 503 PM CDT THU APR 23 2015
GETTING REPORTS OF SNOW FROM STANLEY AND PARSHALL AREAS. LOOKS
LIKE COOLING TO THE WET BULB IS CREATING ENOUGH COOLING FOR SNOW
LATE THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
SHOWERS THIS AFTERNOON THROUGH TONIGHT HIGHLIGHT THE SHORT TERM
FORECAST.
OUTSIDE OF THE HIGHWAY 200 CORRIDOR...THE MAJORITY OF
PRECIPITATION IS NOT REACHING THE GROUND DUE TO DRY AIR IN THE
SUB-800 MB LAYER. THE 16-18 UTC HRRR ITERATIONS HAVE THE BEST
HANDLING OF THE ONGOING PRECIPITATION...ESPECIALLY THAT WHICH IS
REACHING THE GROUND...AND WILL WEIGH HEAVILY ON THEIR SOLUTIONS
THROUGH AFTERNOON AND EVENING. THEREAFTER...THE 12 AND INCOMING 18
UTC GLOBAL AND HIGH RESOLUTION SUITES ARE IN AGREEMENT ON ELEVATED
SHOWERS DEVELOPING TONIGHT ACROSS THE JAMES AND INTO THE RED RIVER
VALLEYS BY 05 UTC WITH A MODEST LOW LEVEL JET AHEAD OF THE
SURFACE LOW ACROSS WESTERN SOUTH DAKOTA. GIVEN MARGINALLY POSITIVE
SHOWALTER VALUES...WILL NOT PUT IN THUNDER AT THIS TIME. FRIDAY
APPEARS TO BE DRY ACROSS WESTERN AND CENTRAL NORTH DAKOTA BETWEEN
THE STRONGER LOW ACROSS THE CENTRAL PLAINS AND THE PACIFIC
NORTHWEST TROUGH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
A SPLIT FLOW THROUGH THE WEEKEND WITH PERIODS OF INTERACTION
BETWEEN THE SOUTHERN STREAM AND NORTHERN STREAM. THIS WILL
ULTIMATELY SET UP AN INCREASINGLY WET/UNSETTLED WEATHER PATTERN
THROUGH EARLY NEXT WEEK. TWO MAIN SHORTWAVES TO PUSH ACROSS WESTERN
AND CENTRAL NORTH DAKOTA FRIDAY NIGHT THROUGH MONDAY. THE LATEST
ECMWF IS ADVERTISING A MORE CONTINUOUS RAIN OVER THE WEEKEND INTO
MONDAY...WHILE THE GFS/CANADIAN GEM HAS A MORE DISTINCT START/END
TIME WITH EACH WAVE. UTILIZED A BLEND OF THE ABOVE MODELS ABOVE.
EXPECT A BRIEF DRYING AND WARMING TREND BY MIDWEEK...THEN A
PROGRESSIVE AND POSSIBLY UNSETTLED WEATHER PATTERN SETTING UP LATE
IN THE EXTENDED.
FOR FRIDAY NIGHT THROUGH SATURDAY...A TRANSITORY 700MB-500MB RIDGE
DEVELOPS OUT AHEAD OF AN APPROACHING SHORTWAVE TROUGH SLIDING INTO
THE NORTHERN ROCKIES. THIS SHOULD KEEP CONDITIONS DRY FOR MOST AREAS
FRIDAY NIGHT BEFORE EAST TO SOUTHEAST WINDS ADVECT AN AREA OF
MOISTURE INTO THE WEST. THIS MOISTURE WILL CONVERGE INTO AN
APPROACHING SURFACE COLD FRONT IN EASTERN MONTANA. THUS POPS BECOME
LIKELY THEN CATEGORICAL SATURDAY IN THE WEST...WITH DRIER CONDITIONS
IN THE EAST AS MID LEVEL RIDGING REMAINS INTACT UNTIL 00Z SUNDAY.
SATURDAY NIGHT THROUGH MONDAY NIGHT...AS MENTIONED ABOVE THERE ARE
DIFFERENCES IN THE ECMWF AND GFS/GEM...ESPECIALLY SATURDAY NIGHT
THROUGH SUNDAY. PER GFS/GEM...THE SURFACE LOW/COLD FRONT AND SHORTWAVE
MOVE INTO SOUTHERN CANADA WITH SHOWERS DIMINISHING SATURDAY NIGHT
INTO SUNDAY. THE TRAILING COLD FRONT STALLS UNDER A SOUTHWEST FLOW
ALOFT...WITH LOW LEVEL SOUTH TO SOUTHEAST WINDS FEEDING MOISTURE
INTO NORTH DAKOTA. THE GFS/GEM MODELS TREND TOWARD A CESSATION TO
THE PRECIPITATION UNTIL SUNDAY NIGHT WHEN THE THE FRONT BECOMES
RE-ENERGIZED AS THE NEXT SHORTWAVE TROUGH APPROACHES. WITH THE
SURFACE COLD FRONT AND SOUTHERN STREAM MOISTURE ALREADY IN
PLACE...THIS SETS THE STAGE FOR A MORE WIDESPREAD PRECIPITATION
EVENT SUNDAY NIGHT THROUGH MONDAY. AS MENTIONED ABOVE THE LATEST
ECMWF REALLY DOES NOT STOP THE PRECIPITATION WITH THE INITIAL
SHORTWAVE...RATHER KEEPS THE SURGE MAINLY CONTINUOUS IN THE WEST AND
SLOWLY SPREADS IT EAST AND NORTH THROUGH MONDAY. TOTAL PRECIPITATION
AMOUNTS COULD RANGE BETWEEN A HALF INCH TO ONE INCH IN THE WEST TO
AROUND A QUARTER OF AN INCH IN CENTRAL NORTH DAKOTA THROUGH MONDAY NIGHT.
MONDAY NIGHT THROUGH THURSDAY...GOOD AGREEMENT THAT PRECIPITATION
WILL BE EAST OF THE JAMES RIVER VALLEY BY 12Z TUESDAY FOLLOWED BY
UPPER RIDGING TUESDAY AND WEDNESDAY. WARM AIR ADVECTION RAMPS UP
LATE TUESDAY INTO WEDNESDAY...AHEAD OF AN ADVANCING COLD FRONT WHICH
IS FORECAST TO CROSS SOUTHERN CANADA WEDNESDAY AFTERNOON/EVENING. THE GFS
SHOWS SOME LIGHT PRECIPITATION DEVELOPING IN THE NORTH BEHIND THE
FRONT WEDNESDAY AFTERNOON. THE ECMWF IS ABOUT 6HRS SLOWER WITH THE
COLD FRONT...NOT ARRIVING INTO THE NORTHWEST UNTIL AROUND 00Z
THURSDAY. THURSDAY LOOKS DRY...ALTHOUGH THIS MAY BE BRIEF AS
THE NEXT SYSTEM IS ALREADY APPROACHING THURSDAY NIGHT INTO FRIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 724 PM CDT THU APR 23 2015
SURFACE LOW PRESSURE ACROSS WESTERN SOUTH DAKOTA WILL MAINTAIN A
SOUTHEAST TO EASTERLY SURFACE WIND FLOW ACROSS THE STATE. AN UPPER
LEVEL RIPPLE ION THE FLOW ALOFT WILL GENERATE AN AREA OF RAIN
ACROSS SOUTHEAST NORTH DAKOTA TONIGHT. CEILINGS FOR JAMESTOWN
LIKELY TO FALL TO OW VFR ACROSS AFTER 12Z. OTHERWISE VFR ALL
OTHER SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AYD
LONG TERM...KS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
654 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 655 PM CDT THU APR 23 2015
THE MAIN CHALLENGE TONIGHT WILL BE WHO WILL GET MEASURABLE RAIN.
THERE IS A BAND OF WEAKENING SHOWERS MOVING INTO EASTERN ND...AND
THIS ACTIVITY IS DRYING UP AS IT ENTERS A VERY DRY AIRMASS WITH
DEWPOINTS IN THE TEENS AND SINGLE DIGITS. WE WILL REMOVE MOST POPS
THROUGH 6Z TONIGHT...WITH SOME ELEVATED SHOWERS LATER TONIGHT ON
THE NOSE OF A STRENGTHENING 40-45KT LLJ INTO NE SD. MOISTURE
TRANSPORT SHOULD OCCUR AND PWATS ARE PROGGED TO RISE TO AROUND
0.90 IN THE SOUTH BY LATE TONIGHT. SHOWALTERS EVEN GET SLIGHTLY
NEGATIVE IN NORTHEAST SD...BUT WILL KEEP THE PRECIP JUST SHOWERS
AND NOT MENTION THUNDER JUST YET. THERE SHOULD BE DEEPER LAYERED
SATURATION SO WILL KEEP THE POPS LATER TONIGHT INTO THU...WITH THE
BEST CHANCE FOR RAINFALL IN THE SOUTHERN 1/3 OF THE AREA. MOST OF
THE PRECIP SHOULD FALL AS RAIN...ALTHOUGH SOUNDINGS NEAR KBJI
INDICATE THE CHANCE FOR SOME SNOW MIXING IN SO WILL MAINTAIN A MIX
HERE LATE TONIGHT INTO THU MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 321 PM CDT THU APR 23 2015
PRECIP CHANCES AND TYPE TONIGHT AND TOMORROW WILL BE THE MAIN
FORECAST ISSUE FOR THE SHORT TERM.
WEST TO SOUTHWEST FLOW CONTINUES OVER THE REGION WITH VARIOUS WEAK
SHORTWAVES MOVING THROUGH THE FLOW. ONE WEAK LEAD SHORTWAVE HAS
ALREADY BEEN HEADING TOWARDS WESTERN ND...WITH SOME DECENT RADAR
RETURNS OVER THAT PART OF THE STATE. SOME LIGHT RAIN HAS BEEN
REACHING THE GROUND...ALTHOUGH NOT AS MUCH AS RADAR WOULD
INDICATE. DEW POINTS OVER THE CWA HAVE BEEN IN THE SINGLE DIGITS
TO TEENS. THE RAP AND HRRR HAVE THE PRECIP DISSIPATING AS IT MOVES
EAST...WHICH SEEMS REASONABLE GIVEN THE VERY DRY AIR. THINK THE
BETTER SHOT FOR PRECIPITATION WILL BE LATER TONIGHT AS A MORE
SOUTHERN SHORTWAVE MOVES INTO WY AND SFC LOW PRESSURE DEVELOPS
OVER WESTERN SD. THERE WILL BE SOME MID LEVEL WARM AIR
ADVECTION/FRONTOGENESIS OVER MAINLY THE SOUTHERN COUNTIES TONIGHT.
SOME OF THE MODELS HAVE SEVERAL TENTHS OF QPF TONIGHT...BUT GIVEN
HOW LONG IT WILL TAKE TO SATURATE WILL LEAN TOWARDS THE LOWER END
FOR PRECIP AMOUNTS. MODEL SOUNDINGS SHOW MOSTLY ABOVE ZERO AS THE
COLUMN SATURATES...BUT SOME SNOW MIXING IN ON THE NORTHERN EDGE OF
THE PRECIP IS NOT OUT OF THE QUESTION.
TOMORROW...THE SHORTWAVE TROUGH MOVES OUT INTO THE PLAINS...AND
THERE SHOULD BE A DECENT AMOUNT OF PRECIP OVER THE SOUTHERN
COUNTIES SPREADING NORTH AND EAST AS THE BEST MID LEVEL BAROCLINIC
ZONE LIFTS ACROSS THE AREA. CONTINUED TO KEEP LIKELY POPS FOR A
RAIN/SNOW MIX OVER THE SOUTHEASTERN COUNTIES FOR FRIDAY
MORNING...LINGERING INTO THE AFTERNOON. THE CLOUDS AND PRECIP
SHOULD KEEP TEMPS IN THE LOWER 40S IN THE EAST...BUT THINK THERE
WILL BE ENOUGH PEAKS OF SUN TO GET ABOVE 50 IN THE WESTERN
COUNTIES WHERE IT WILL BE DRIER. PRECIP WILL BEGIN TO TAPER OFF
FRIDAY NIGHT BUT KEPT SOME LOWER POPS THROUGH SATURDAY MORNING IN
OUR SOUTHEAST TO COORDINATE WITH NEIGHBORS. CLOUDS AND INCREASING
EASTERLY WINDS WILL KEEP TEMPS IN THE 30S FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 321 PM CDT THU APR 23 2015
SATURDAY AND SUNDAY...UPPER RIDGING WILL BUILD IN BRIEFLY...BUT
GIVE WAY AS THE NEXT SPLIT TROUGH BEGINS TO MOVE OUT FROM THE
WESTERN CONUS BY LATE SUNDAY. SFC HIGH PRESSURE OVER ONTARIO
SATURDAY WILL BRING EAST TO SOUTHEASTERLY WINDS WITH DRIER AIR INTO
THE CWA AND HIGHS SHOULD REACH THE 50S WITH AT LEAST SOME BREAKS
IN THE CLOUDS. TEMPS WILL BE EVEN WARMER FOR SUNDAY AS THE SFC
HIGH MOVES OFF TO THE EAST AND A TROUGH DEVELOPING OVER THE
WESTERN PLAINS STARTS SOME WARMER AIR MOVING BACK TO THE NORTH.
THE ECMWF TRIES TO BRING SOME PRECIP INTO OUR WESTERN COUNTIES FOR
SUNDAY AS THE NEXT UPPER SYSTEM APPROACHES...BUT THE OTHER MODELS
ARE A BIT SLOWER. INCLUDED SOME LOW POPS IN THE DEVILS LAKE BASIN
BUT THINK THE MAIN PRECIP WILL HOLD OFF UNTIL AFTER 00Z MONDAY.
SUNDAY NIGHT THROUGH THURSDAY...LONG WAVE UPPER LEVEL LOW PRESSURE
THAT WAS NORTH OF THE GREAT LAKES WILL MOVE OFF THE NEW ENGLAND
STATES EARLY IN THE PERIOD. BUT LONG WAVE TROUGH BECOMES RE-
ESTABLISHED OVER THE NORTHEAST STATES BY THE END OF THE PERIOD.
LONG WAVE UPPER RIDGE BUILDS OVER THE US AND CANADIAN ROCKIES THIS
PERIOD. ECMWF AND GFS WERE TRENDING FASTER THEN SLOWER OVER THE
LAST COUPLE MODEL RUNS. THE GFS IS FASTER THAN THE ECMWF. SO WILL
PREFER THE SLOWER ECMWF.
KEPT POPS FROM PREVIOUS RUN FOR MON NIGHT THROUGH TUE NIGHT.
APPROACHING UPPER LEVEL TROUGH WILL PRODUCE PRECIP FOR MON AND TUE
AND ANOTHER SHORT WAVE TROUGH IS EXPECTED WED NIGHT THROUGH THU
NIGHT.
HIGH TEMPS WERE INCREASED TWO TO FIVE DEGREES FOR MON TUE AND WED.
HIGH TEMPS DECREASED TWO TO FIVE DEGREES FOR THU FROM THIS MORNINGS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 655 PM CDT THU APR 23 2015
VFR CIGS WILL LOWER OVERNIGHT AS SATURATION OCCURS WITH STRONG MID
LEVEL WAA. E/SE WINDS WILL ALSO INCREASE AND GUST OVER 20KT LATER
TONIGHT AND THU MORNING. HAVE MENTIONED A SHOWER NEAR FARGO...AND
KEPT ALL OTHER AREAS DRY THROUGH THE PERIOD. CIGS SHOULD LOWER
INTO THE MVFR RANGE FOR KFAR/KBJI...AND WE WILL HAVE TO MONITOR
THE POTENTIAL FOR OTHER AREAS. THERE IS PLENTY OF DRY AIR IN THE
LOWER LEVELS...SO CIGS COULD REMAIN IN THE VFR RANGE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...JR/HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
153 PM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED...A FEW ADJUSTMENTS TO THE FORECAST FOR THIS AFTERNOON.
WE ARE RECEIVING SEVERAL REPORTS OF MIXED PRECIPITATION OVER THE
AREA WITH SNOW AND GRAUPEL MIXING WITH THE RAIN. I WILL ADJUST
THE FORECAST TO MENTION THE MIXED PRECIPITATION. HIGH TEMPERATURES
ARE NOT RISING AS FAST AS EARLIER ANTICIPATED. I WILL BUMP THE
HIGH TEMPERATURES BACK A FEW DEGREES INTO THE MID 40S. I WILL ALSO
INCREASE THE CLOUD COVER.
ORIGINAL...UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC
REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE
AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL
CONTINUE SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA
EARLY THIS MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS
THROUGH THE PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY
SOUTHERN AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST
BY 14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE
AREA LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME
BREAKS IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT
THROUGH THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT
AND ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN
THE AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM
MORNING LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES
LIKELY ON THE ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SCATTERED SHOWERS WILL CONTINUE TO MOVE EAST ACROSS NORTHEAST OHIO
THROUGH 21Z. THESE SHOWERS WILL IMPACT YNG AND POSSIBLY CAK WITH A
CHANCE OF BRIEF ICE PELLETS MIXING IN. OTHERWISE EXPECTING
PREDOMINANTLY VFR CONDITIONS INTO THIS EVENING...LOWERING TO MVFR
OVERNIGHT IN NE OHIO/NW PA. THERE WILL BE A CHANCE OF SNOW
SHOWERS...MAINLY AT ERI/YNG AFTER 05Z. BREEZY WESTERLY WINDS WITH
GUSTS TO AROUND 25 KNOTS WILL CONTINUE THIS AFTERNOON WITH GUSTS
DROPPING OFF AFTER 00Z. GUSTY WINDS WILL RETURN AFTER 14Z ON
THURSDAY.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA. LOW CONFIDENCE IN NON VFR CONDITIONS
RETURNING SATURDAY NIGHT THROUGH SUNDAY NIGHT.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...GARNET
SHORT TERM...TK
LONG TERM...DJB
AVIATION...KEC
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1200 PM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED...A FEW ADJUSTMENTS TO THE FORECAST FOR THIS AFTERNOON.
WE ARE RECEIVING SEVERAL REPORTS OF MIXED PRECIPITATION OVER THE
AREA WITH SNOW AND GRAUPEL MIXING WITH THE RAIN. I WILL ADJUST
THE FORECAST TO MENTION THE MIXED PRECIPITATION. HIGH TEMPERATURES
ARE NOT RISING AS FAST AS EARLIER ANTICIPATED. I WILL BUMP THE
HIGH TEMPERATURES BACK A FEW DEGREES INTO THE MID 40S. I WILL ALSO
INCREASE THE CLOUD COVER.
ORIGINAL...UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC
REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE
AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL
CONTINUE SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA
EARLY THIS MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS
THROUGH THE PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY
SOUTHERN AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST
BY 14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE
AREA LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME
BREAKS IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT
THROUGH THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT
AND ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN
THE AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM
MORNING LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES
LIKELY ON THE ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHOWERS WILL GRADUALLY MOVE EAST OF THE FORECAST AREA BY MID
MORNING AS WEAK SHORT WAVES MOVES EAST. WINDY CONDITIONS WILL
CONTINUE TODAY WITH WEST WINDS 20-30 KTS AS SECONDARY COLD FRONT
PUSHES THROUGH THIS AFTERNOON. POTENTIAL FOR LAKE EFFECT SNOW NW
PA OVERNIGHT...LITTLE OF NO ACCUMULATION.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...GARNET
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
926 AM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED...A FEW ADJUSTMENTS TO THE MORNING FORECAST. I WILL KEEP
A MENTION OF RAIN OVER THE ENTIRE ARE THIS MORNING AND AFTERNOON
AS DIURNAL CLOUDS AND SHOWERS ARE ALREADY FORMING OVER WESTERN
OHIO AND MICHIGAN. WITH THE COLD AIR AND UPPER LEVEL LOW I EXPECT
WIDELY SCATTERED SHOWER ACTIVITY TO CONTINUE THROUGH THE
AFTERNOON. I HAVE ALSO ADJUSTED THE CLOUD COVER GRIDS TO ACCOUNT
FOR THE CU ALREADY FORMING IN CLOUD COVER BREAKS. CURRENT HIGH
TEMPERATURES MAY BE A FEW DEGREES TOO WARM THIS AFTERNOON. 12Z
SOUNDINGS SUGGEST HIGHS IN THE LOWER 40S. I MAY NEED TO LOWER THE
HIGH TEMPERATURES A FEW DEGREES LATER THIS MORNING. I WILL
CONTINUE TO MONITOR.
ORIGINAL...UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC
REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE
AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL
CONTINUE SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA
EARLY THIS MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS
THROUGH THE PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY
SOUTHERN AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST
BY 14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE
AREA LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME
BREAKS IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT
THROUGH THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT
AND ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN
THE AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM
MORNING LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES
LIKELY ON THE ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHOWERS WILL GRADUALLY MOVE EAST OF THE FORECAST AREA BY MID
MORNING AS WEAK SHORT WAVES MOVES EAST. WINDY CONDITIONS WILL
CONTINUE TODAY WITH WEST WINDS 20-30 KTS AS SECONDARY COLD FRONT
PUSHES THROUGH THIS AFTERNOON. POTENTIAL FOR LAKE EFFECT SNOW NW
PA OVERNIGHT...LITTLE OF NO ACCUMULATION.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...GARNET
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
711 AM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED...UPDATED SKY AND POP GRIDS BASED ON CURRENT SATELLITE AND
RADAR. RADAR LOOPS SHOW TREND REMAINS IN PLACE OF PRECIP MAINLY IN
THE SOUTH AND EASTERN COUNTIES MOVING SOUTHEAST OUT OF THE AREA
THROUGH THE FIRST HALF OF THE MORNING. SATELLITE ALSO SHOWS
CLEARING MOVING IN FROM THE WEST. THIS WILL BE A BRIEF DRY SLOT
THAT SHOULD FILL IN THROUGH LATE MORNING AND EARLY AFTERNOON AS IT
TRAVERSES EAST/SOUTHEAST.
ORIGINAL...UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC
REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE
AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL
CONTINUE SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA
EARLY THIS MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS
THROUGH THE PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY
SOUTHERN AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST
BY 14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE
AREA LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME
BREAKS IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT
THROUGH THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT
AND ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN
THE AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM
MORNING LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES
LIKELY ON THE ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHOWERS WILL GRADUALLY MOVE EAST OF THE FORECAST AREA BY MID
MORNING AS WEAK SHORT WAVES MOVES EAST. WINDY CONDITIONS WILL
CONTINUE TODAY WITH WEST WINDS 20-30 KTS AS SECONDARY COLD FRONT
PUSHES THROUGH THIS AFTERNOON. POTENTIAL FOR LAKE EFFECT SNOW NW
PA OVERNIGHT...LITTLE OF NO ACCUMULATION.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
636 AM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED...UPDATED SKY AND POP GRIDS BASED ON CURRENT SATELLITE AND
RADAR. RADAR LOOPS SHOW TREND REMAINS IN PLACE OF PRECIP MAINLY IN
THE SOUTH AND EASTERN COUNTIES MOVING SOUTHEAST OUT OF THE AREA
THROUGH THE FIRST HALF OF THE MORNING. SATELLITE ALSO SHOWS
CLEARING MOVING IN FROM THE WEST. THIS WILL BE A BRIEF DRY SLOT
THAT SHOULD FILL IN THROUGH LATE MORNING AND EARLY AFTERNOON AS IT
TRAVERSES EAST/SOUTHEAST.
ORIGINAL...UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC
REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE
AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL
CONTINUE SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA
EARLY THIS MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS
THROUGH THE PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY
SOUTHERN AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST
BY 14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE
AREA LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME
BREAKS IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT
THROUGH THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT
AND ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN
THE AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM
MORNING LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES
LIKELY ON THE ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SCATTERED SHOWERS WILL CONTINUE OVERNIGHT WITH A WEAK SHORT WAVE
WILL MOVE ACROSS THE OHIO VALLEY. MAY GET SOME MVFR CONDITIONS IN
THE HEAVIER SHOWERS. WINDY CONDITIONS WILL CONTINUE TODAY...LUCKILY
IT WILL NOT BE AS WINDY AS TUESDAY...MORE LIKE 20-30 KNOT GUSTS
FROM THE WEST.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
328 AM EDT WED APR 22 2015
.SYNOPSIS...
A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER
OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. THIS WILL SUPPORT
BELOW NORMAL TEMPERATURES AND THE CHANCE FOR SOME ON AND OFF RAIN
SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC REGION. AT
THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE AREA
SPREADING RAIN SHOWERS INVOF THE FRONT. THE FRONT WILL CONTINUE
SOUTHEAST TODAY AND SHOULD BE MOVING EAST OF THE AREA EARLY THIS
MORNING. EXPECTING SHOWERS TO CONTINUE MOST AREAS THROUGH THE
PREDAWN HOURS. AFTER DAWN SHOWERS SHOULD AFFECT MAINLY SOUTHERN
AND EASTERN COUNTIES WITH THE MAIN AREA OF RAIN SOUTHEAST BY
14-15Z. HRRR DOES SHOW SOME REDEVELOPMENT EASTERN HALF OF THE AREA
LATE MORNING SO WILL HOLD ONTO POPS THERE. THERE ARE SOME BREAKS
IN THE CLOUDS MAINLY ACROSS NWRN OHIO AND SRN LWR MI BUT THROUGH
THE MORNING THIS SHOULD FILL IN WITH SUCH COLD AIR ALOFT AND
ADDITIONAL WRAP AROUND MOISTURE DROPPING ACROSS THE AREA IN THE
AFTERNOON. HIGHS TODAY WILL LIKELY NOT RISE TOO MUCH FROM MORNING
LOWS GIVEN THE COLD ADVECTION ACROSS THE AREA. RISES LIKELY ON THE
ORDER OF 5 DEGREES OR SO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA
THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS
THE AREA AROUND THE CLOSED STAGNANT UPPER LOW. THE CIRCULATION
SHIFTS EAST ENOUGH BY FRIDAY TO GET DRIER AIR INTO THE AREA BUT
STILL NO WARM UP WITH 850MB TEMPS BELOW ZERO AND WELL BELOW NORMAL.
SATURDAY MOISTURE WILL RETURN AS LOW PRESSURE MOVES EAST ACROSS
THE LOWER OHIO VALLEY. DEPENDING ON THE PATH WE COULD GET SHOWERS
ASSOCIATED WITH THE LOW INTO THE AREA SO DID PUT IN A CHANCE POP
WESTERN TWO THIRDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FORECAST PERIOD.
BOTH MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE PUSHING
SOUTHEAST ACROSS THE AREA ON SUNDAY. HIGH REMAINS ENTRENCHED OVER
THE FORECAST AREA MONDAY AS LOW PRESSURE TRACKS UP THE EAST COAST.
MODELS DIVERGE ON TUESDAY AS GFS MOVES LOW PRESSURE SYSTEM ACROSS
THE UPPER OHIO VALLEY WHILE ECMWF CONTINUES WITH HIGH PRESSURE OVER
THE AREA. WILL CONTINUE WITH PREVIOUS FORECAST WHICH TRENDED TOWARD
GFS WITH LOW CHANCE POPS.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SCATTERED SHOWERS WILL CONTINUE OVERNIGHT WITH A WEAK SHORT WAVE
WILL MOVE ACROSS THE OHIO VALLEY. MAY GET SOME MVFR CONDITIONS IN
THE HEAVIER SHOWERS. WINDY CONDITIONS WILL CONTINUE TODAY...LUCKILY
IT WILL NOT BE AS WINDY AS TUESDAY...MORE LIKE 20-30 KNOT GUSTS
FROM THE WEST.
.OUTLOOK...MVFR CEILINGS AT TIMES THURSDAY MAINLY EXTREME NORTHEAST
OH AND NORTHWEST PA.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE INTO THURSDAY NIGHT. GUSTY WEST
TO SOUTHWEST WINDS WILL CONTINUE INTO THURSDAY NIGHT AS LOW PRESSURE
SLOWLY DRIFTS ACROSS EASTERN CANADA. WINDS WILL BECOME LIGHTER BY
FRIDAY AND FRIDAY NIGHT AS HIGH PRESSURE BUILDS SLOWLY OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT FRIDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS NORMAN OK
1039 PM CDT THU APR 23 2015
.UPDATE...
UPDATE TO PRECIP/WX THIS MORNING...
&&
.DISCUSSION...
THE WARM FRONT CONTINUES TO SLOWLY LIFT NORTHWARD... WITH
MESOSCALE GUIDANCE CONTINUING TO INDICATE INCREASING CHANCES FOR
SHOWERS DEVELOPING ACROSS TEXOMA THROUGH THE EARLY MORNING HOURS
AND POSSIBLY ACROSS NORTHERN OKLAHOMA AS WELL. ADJUSTED POPS
SLIGHTLY AS THIS SOLUTION SEEMS REASONABLE GIVEN DEWPOINT AXIS
INTO THE REGION AND AVAILABLE LIFT FROM A SUBTLE H700 WAVE MOVING
E/NE INTO SWRN OK/WRN N TX. KEPT CHANCE POPS AS COVERAGE REMAINS A
CHALLENGE.
JTK
&&
.PREV DISCUSSION... /ISSUED 1029 PM CDT THU APR 23 2015/
AVIATION...
IFR CONDITIONS IN LOW CEILINGS AND FOG WILL BE COMMON IN SOUTHWEST
OKLAHOMA THROUGH TONIGHT. MVFR CONDITIONS ARE EXPECTED ACROSS
NORTHERN OKLAHOMA. SHOWERS AND A FEW THUNDERSTORMS MAY FORM BEFORE
SUNRISE. A DRYLINE IS EXPECTED TO GENERATE SCATTERED THUNDERSTORMS,
SOME SEVERE, FRIDAY AFTERNOON IN THE EASTERN HALF OF OKLAHOMA.
PREV DISCUSSION... /ISSUED 418 PM CDT THU APR 23 2015/
DISCUSSION...
STRATUS HAS INHIBITED HEATING ACROSS THE ENTIRE AREA TODAY WITH
PERSISTENT ESE LOW LEVEL FLOW BEHIND THE FRONT. DO NOT EXPECT ANY
STORMS BEFORE 00Z. HOWEVER...LATER TONIGHT A NOCTURNAL LLJ WILL
DEVELOP OVER CENTRAL OK ISENTROPIC ASCENT WILL FOLLOW. IN
ADDITION...A SUBTLE MID LEVEL SHORTWAVE TROUGH WILL ALSO MOVE OUT
OF THE PANHANDLE ~06Z. NAM AND RAP SOUNDINGS ALSO INDICATE AROUND
1500 J/KG OF ELEVATED CAPE NEAR 06-09Z WITH PLENTY OF DEEP LAYER
SHEAR PRESENT. WOULD NOT BE SURPRISED IF A COUPLE OF SEVERE
STORMS DEVELOP OVERNIGHT ACROSS CENTRAL/N CENTRAL OK. THEN...LATE
TONIGHT THROUGH LATE TOMORROW MORNING A MID LEVEL SHORTWAVE
TROUGH WILL LIFT OUT OF WEST TEXAS AND APPROACH THE SE RED RIVER
VALLEY. MODELS CONTINUE TO INDICATE SCATTERED ACTIVITY OVER OUR SE
ZONES THROUGH MOST OF THE DAY.
THE PREVIOUS WILL LIKELY LIMIT INSTABILITY AT LEAST ALONG THE
SOUTHERN HALF OF THE DRYLINE FRI AFT/EVE. FURTHER NORTH ALONG THE
DRYLINE...SOMEWHERE FROM AROUND OKC TO TO SWO TO PNC...THERE MAY
BE ENOUGH INSTABILITY FOR A FEW STORMS TO DEVELOP BEFORE THEY MOVE
EAST OUT OF AREA DURING THE EVENING HOURS. IF STORMS DO MANAGE TO
DEVELOP LATE TOMORROW AFTERNOON ALONG AND EAST OF I35...THEY WILL
LIKELY BECOME SEVERE WITH DAMAGING WINDS...HAIL...AND PERHAPS
TORNADOES POSSIBLE.
DRIER CONDITIONS ARE EXPECTED SATURDAY AND TEMPS WILL CLIMB WELL
ABOVE AVERAGE OVER THE SW AS STRONG DOWNSLOPE FLOW DEVELOPS AHEAD
OF A COLD FRONT SLOWLY STALLING OUT. MAXTS IN THE LOW 90S APPEAR
POSSIBLE FOR PORTIONS OF WESTERN N TX. THE ATTENTION THEN TURNS TO
LATE SUNDAY THROUGH MONDAY AS A FAIRLY DEEP UPPER LOW TRAVERSES NM
AND MOVES INTO THE SOUTHERN PLAINS MON AM. WILL CONTINUE TO SLOWLY
INCREASE POPS FOR EARLY NEXT WEEK WITH THIS SYSTEM. IT WILL DRY
OUT AND COOL OFF TUES-WED BEHIND A COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 62 80 56 85 / 40 30 20 0
HOBART OK 61 84 55 87 / 30 10 0 0
WICHITA FALLS TX 64 84 58 89 / 20 20 10 0
GAGE OK 58 81 52 84 / 20 20 10 0
PONCA CITY OK 59 81 58 83 / 50 30 20 10
DURANT OK 63 79 62 88 / 40 70 40 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1029 PM CDT THU APR 23 2015
.AVIATION...
IFR CONDITIONS IN LOW CEILINGS AND FOG WILL BE COMMON IN SOUTHWEST
OKLAHOMA THROUGH TONIGHT. MVFR CONDITIONS ARE EXPECTED ACROSS
NORTHERN OKLAHOMA. SHOWERS AND A FEW THUNDERSTORMS MAY FORM BEFORE
SUNRISE. A DRYLINE IS EXPECTED TO GENERATE SCATTERED THUNDERSTORMS,
SOME SEVERE, FRIDAY AFTERNOON IN THE EASTERN HALF OF OKLAHOMA.
&&
.PREV DISCUSSION... /ISSUED 418 PM CDT THU APR 23 2015/
DISCUSSION...
STRATUS HAS INHIBITED HEATING ACROSS THE ENTIRE AREA TODAY WITH
PERSISTENT ESE LOW LEVEL FLOW BEHIND THE FRONT. DO NOT EXPECT ANY
STORMS BEFORE 00Z. HOWEVER...LATER TONIGHT A NOCTURNAL LLJ WILL
DEVELOP OVER CENTRAL OK ISENTROPIC ASCENT WILL FOLLOW. IN
ADDITION...A SUBTLE MID LEVEL SHORTWAVE TROUGH WILL ALSO MOVE OUT
OF THE PANHANDLE ~06Z. NAM AND RAP SOUNDINGS ALSO INDICATE AROUND
1500 J/KG OF ELEVATED CAPE NEAR 06-09Z WITH PLENTY OF DEEP LAYER
SHEAR PRESENT. WOULD NOT BE SURPRISED IF A COUPLE OF SEVERE
STORMS DEVELOP OVERNIGHT ACROSS CENTRAL/N CENTRAL OK. THEN...LATE
TONIGHT THROUGH LATE TOMORROW MORNING A MID LEVEL SHORTWAVE
TROUGH WILL LIFT OUT OF WEST TEXAS AND APPROACH THE SE RED RIVER
VALLEY. MODELS CONTINUE TO INDICATE SCATTERED ACTIVITY OVER OUR SE
ZONES THROUGH MOST OF THE DAY.
THE PREVIOUS WILL LIKELY LIMIT INSTABILITY AT LEAST ALONG THE
SOUTHERN HALF OF THE DRYLINE FRI AFT/EVE. FURTHER NORTH ALONG THE
DRYLINE...SOMEWHERE FROM AROUND OKC TO TO SWO TO PNC...THERE MAY
BE ENOUGH INSTABILITY FOR A FEW STORMS TO DEVELOP BEFORE THEY MOVE
EAST OUT OF AREA DURING THE EVENING HOURS. IF STORMS DO MANAGE TO
DEVELOP LATE TOMORROW AFTERNOON ALONG AND EAST OF I35...THEY WILL
LIKELY BECOME SEVERE WITH DAMAGING WINDS...HAIL...AND PERHAPS
TORNADOES POSSIBLE.
DRIER CONDITIONS ARE EXPECTED SATURDAY AND TEMPS WILL CLIMB WELL
ABOVE AVERAGE OVER THE SW AS STRONG DOWNSLOPE FLOW DEVELOPS AHEAD
OF A COLD FRONT SLOWLY STALLING OUT. MAXTS IN THE LOW 90S APPEAR
POSSIBLE FOR PORTIONS OF WESTERN N TX. THE ATTENTION THEN TURNS TO
LATE SUNDAY THROUGH MONDAY AS A FAIRLY DEEP UPPER LOW TRAVERSES NM
AND MOVES INTO THE SOUTHERN PLAINS MON AM. WILL CONTINUE TO SLOWLY
INCREASE POPS FOR EARLY NEXT WEEK WITH THIS SYSTEM. IT WILL DRY
OUT AND COOL OFF TUES-WED BEHIND A COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 62 80 56 / 20 40 30 20
HOBART OK 66 61 84 55 / 20 20 10 0
WICHITA FALLS TX 72 64 84 58 / 10 20 20 10
GAGE OK 66 58 81 52 / 20 20 20 10
PONCA CITY OK 67 59 81 58 / 10 30 30 20
DURANT OK 67 63 79 62 / 20 30 70 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
03/09/09
AREA FORECAST DISCUSSION
NWS TULSA OK
1112 PM CDT TUE APR 21 2015
.DISCUSSION...
THE 06Z TAF DISCUSSION IS INCLUDED BELOW.
&&
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
THE 00Z SUITE OF DATA WAS NOT AS PESSIMISTIC OVERALL WITH REGARD
TO LOWER CIGS. BASED ON HRRR DATA...A COMPLEX OF STORMS WILL
ORGANIZE AHEAD OF SURGING FRONT AND WILL AFFECT MOST SITES EARLY
WEDNESDAY MORNING. A PERIOD OF MVFR CONDITIONS IS POSSIBLE WITH
THE ACTIVITY...OTHERWISE VFR CIGS WILL PREVAIL. SOME CHANCE OF
SHRA AND TSRA WILL PERSIST THRU THE END OF THE FCST PD...AND HAVE
CHOSEN TO HANDLE THIS WITH PROB30 GROUPS.
LACY
&&
.PREV DISCUSSION... /ISSUED 954 PM CDT TUE APR 21 2015/
DISCUSSION...
MINOR WAVE NORTH TEXAS AND OKLAHOMA PANHANDLE REGION
JUST STARTING TO PRODUCE LIGHTNING. 00Z WRF ALONG WITH
THE LAST SEVERAL HOURLY RUNS OF HR^3 GROW CONVECTION
OVERNIGHT TO WEST AND PUSH IT THROUGH EASTERN OKLAHOMA
VERY LATE TONIGHT AND WEDNESDAY MORNING. RAISED POPS
FOR WEDNESDAY MORNING. LEFT OVER BOUNDARIES MAY BECOME
FOCUS OF MORE SIGNIFICANT THUNDER WEDNESDAY AFTERNOON
AND EVENING. STILL LOOKS LIKE BEST BET NEAR RED RIVER.
GW
PREV DISCUSSION... /ISSUED 608 PM CDT TUE APR 21 2015/
DISCUSSION...
THE 00Z TAF DISCUSSION IS INCLUDED BELOW.
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR CONDITIONS WILL PREVAIL THRU MUCH OF THE NIGHT TONIGHT...THRU
ABOUT 09Z. MVFR CIGS ARE EXPTD AT THE TAF SITES IN THE 09Z TO 12Z
TIME FRAME. SOME SCT SHRA OR TSRA ARE POSSIBLE AS A FRONTAL
BOUNDARY DROPS DOWN INTO THE REGION. CONDITIONS SHOULD IMPROVE BY
MIDDAY WEDNESDAY AT MOST SITES...WITH THE EXCEPTION OF
KMLC...WHICH IS FORECAST TO REMAIN MVFR THRU THE DAY.
LACY
PREV DISCUSSION... /ISSUED 254 PM CDT TUE APR 21 2015/
DISCUSSION...
CENTRAL PLAINS FRONT WILL DROP SOUTH TONIGHT...SETTLING TO NEAR THE
OK/TX BORDER BY WEDNESDAY MORNING. LOW-LEVEL MOISTURE WILL IMPROVE
THROUGH THE NIGHT...WITH LOWER 60S DEWPOINTS LIKELY ACROSS SE OK BY
WEDNESDAY MORNING. A MARGINAL SEVERE WEATHER THREAT WILL EXIST EARLY
WEDNESDAY...AS ELEVATED STORMS NORTH OF THE FRONTAL BOUNDARY WILL
POSE A HAIL THREAT. SOME OF THIS ACTIVITY MAY FESTER INTO THE
AFTERNOON...WITH THE SEVERE WEATHER CHANCES RISING A BIT AS
INSTABILITY INCREASES. ADDITIONAL THUNDERSTORMS MAY FIRE ALONG THE
DRYLINE OVER WRN TX LATE IN THE DAY...WITH THUNDERSTORM CLUSTERS
WORKING E AND SE OVERNIGHT ACROSS PARTS OF SRN OK/NRN TX. OVERALL
SEVERE WEATHER THREAT MAINLY BE FOR LARGE HAIL AND DAMAGING
WINDS...ALTHOUGH A LOW-END TORNADO THREAT WILL EXIST (FROM LATE
AFTERNOON INTO THE EARLY EVENING) FOR STORMS NEAR THE SYNOPTIC
BOUNDARY AND VARIOUS OUTFLOW BOUNDARIES.
SURFACE RIDGING ALONG WITH A MORE STABLE AIRMASS SHOULD KEEP
THURSDAY FAIRLY QUIET...ALTHOUGH HAVE KEPT SOME LOW POPS FOR A FEW
SHOWERS AND PERHAPS A THUNDERSTORM.
SEVERE WEATHER CHANCES...POTENTIALLY SIGNIFICANT AT THAT...RETURN BY
FRIDAY. ECMWF/GFS SIMILAR IN EJECTING AN UPPER CYCLONE INTO THE
CENTRAL PLAINS...WITH A STRONG 75+ KT MID-LEVEL JET SETTING UP
ACROSS THE SRN PLAINS. FORECAST LOW-LEVEL MOISTURE FIELDS SHOW
DRYLINE SURGING INTO CENTRAL OK BY FRIDAY AFTERNOON...WITH
CONVECTION PEELING OFF INTO ERN OK/WRN AR LATE IN THE DAY AND INTO
FRIDAY EVENING. MAIN COMPLICATING FACTOR WILL THE QUALITY OF
MOISTURE/INSTABILITY AS ECMWF/GFS ALSO SHOW SIGNIFICANT QPF EARLY IN
THE DAY ACROSS NRN TX. THIS COULD HAVE A HUGE IMPACT ON WHERE THE
WARM SECTOR SETS UP DURING THE AFTERNOON...AND THE POTENTIAL EXISTS
(IF ECMWF/GFS QPF VERIFIES) THAT THE WARM SECTOR MOSTLY REMAINS TO
OUR SOUTH. THIS IS STILL A FEW DAYS AWAY AND WE`LL CONTINUE TO TWEAK
THE FORECAST SO PLEASE STAY TUNED.
THE WEEKEND IS LOOKING MOSTLY DRY...WITH PRECIPITATION CHANCES
RETURNING BY SUNDAY NIGHT AND INTO EARLY NEXT WEEK AS ANOTHER UPPER
SYSTEM APPROACHES. EXTENDED MODELS ARE SHOWING VARYING TIMING
DIFFERENCE...SO HAVE KEPT POPS RATHER LOW AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 51 66 51 68 / 30 60 40 40
FSM 51 73 56 67 / 10 60 40 30
MLC 53 74 57 71 / 10 60 40 30
BVO 48 65 45 66 / 30 30 20 30
FYV 48 67 49 62 / 20 60 30 30
BYV 50 63 45 59 / 20 30 20 30
MKO 49 71 52 68 / 20 60 40 30
MIO 48 65 45 64 / 30 30 20 40
F10 54 71 54 69 / 20 70 40 30
HHW 53 75 60 73 / 10 70 60 30
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...30
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
1124 PM PDT TUE APR 21 2015
.UPDATE...THE ATMOSPHERE IS STABILIZING AND THE LATEST SHORT TERM
FORECAST SHOW LESS CONVECTION POTENTIAL. THEREFOR WE HAVE REMOVED
THUNDERSTORMS IN THE FORECAST FOR THE SECOND HALF OF TONIGHT. THE
SHOWERS WILL CONTINUE TO MOVE EAST AND AREAS FROM GERBER RESERVOIR
SOUTH INTO MEDICINE LAKE OF EASTERN SISKIYOU COUNTY SHOULD SEE
MOST OF THE MODERATE SHOWERS OVERNIGHT...WITH SHOWER COVERAGE
DECREASING TO ISOLATED OVERNIGHT. /FB
&&
.AVIATION...FOR THE 22/06Z TAF CYCLE...ALONG THE COAST NORTH OF
PORT ORFORD, MVFR CIGS WILL GRADUALLY LIFT TO VFR LATER WEDNESDAY
MORNING OR AFTERNOON. OFFSHORE FLOW WILL RESULT IN VFR ALONG THE
SOUTH COAST THROUGH WEDNESDAY.
THE REST OF THE WEST SIDE TO THE CASCADES WILL BE MOSTLY VFR
THOUGH AREAS OF MVFR AND PARTIAL TERRAIN OBSCURATIONS WILL DEVELOP
AND LAST THROUGH ABOUT MID-LATE MORNING WEDNESDAY. NORTH TO
NORTHWEST CAN BE BREEZY AT TIMES ESPECIALLY IN THE KLAMATH BASIN
AND THE SHASTA VALLEY WHERE SUSTAINED WIND 15 TO 20 KNOTS ARE
EXPECTED WEDNESDAY AFTERNOON. /FB
&&
.PREV DISCUSSION... /ISSUED 847 PM PDT TUE APR 21 2015/
DISCUSSION...THUNDERSTORMS ARE RUMBLING ACROSS SOUTHEAST SISKIYOU
COUNTY FROM MOUNT SHASTA EASTWARD. RADAR AND SATELLITE IMAGERY
SHOW THREE MORE CELLS ONE OF WHICH LOOKS POTENT ARE APPROACHING
THIS AREA FROM SHASTA COUNTY. SOUTHERN SISKIYOU COUNTY AND
NORTHERN KLAMATH COUNTY WERE THE AREAS THAT MODELS PAINTED THE
MOST INSTABILITY SO CONFIDENCE IS HIGH AS WE MOVE FORWARD INTO THE
REST OF THE NIGHT FORECAST TIMEFRAME. THE SHORT TERM HRRR TAKES
THIS UNSTABLE AREA EAST AND BY MIDNIGHT THE AREA OF CONCERNS SHIFT
TO LAKE COUNTY..ESPECIALLY THE LINE ROUGHLY FOLLOWING HIGHWAY 395
FROM LAKE-HARNEY COUNTY LINE SOUTH INTO MODOC COUNTY...WITH THE
WARNERS SEEING MOST OF THE ACTIVITIES AFTER MIDNIGHT. WE HAVE
UPDATED THE POPS AND WEATHER GRIDS TO INDICATE THIS TREND AND
GRIDS HAVE BEEN POSTED. SO FAR THESE STORMS HAVE PRODUCED RAINFALL
BETWEEN 0.15-0.25 INCH WITH ONE AREA NEAR MCCLOUD RECEIVING ALMOST
HALF AN INCH OF RAIN. /FB
.MARINE...UPDATED 800 PM PDT TUESDAY APR 21, 2015...HIGH PRESSURE
WILL BUILD INTO THE AREA TONIGHT BUT THIS WILL RESULT IN GUSTY
NORTH WINDS AND STEEP TO VERY STEEP SEAS. GALES AND WARNING LEVEL
SEAS ARE EXPECTED AT TIMES SOUTH OF CAPE BLANCO TONIGHT THROUGH
WEDNESDAY NIGHT. THURSDAY THROUGH THE WEEKEND...A SERIES OF
FRONTAL SYSTEMS IS LIKELY TO MOVE THROUGH WITH BUILDING SWELL.
NORTHWEST WINDS WEDNESDAY NIGHT THROUGH FRIDAY ARE EXPECTED TO
BECOME SOUTHWESTERLY THIS WEEKEND. FB
PREV DISCUSSION... /ISSUED 516 PM PDT TUE APR 21 2015/
SHORT TERM...VISIBLE SATELLITE SHOWS THE ATMOSPHERE HAS
DESTABILIZED AS EXPECTED WITH NUMEROUS CUMULUS BUILDUPS OVER THE
HIGHER TERRAIN AND EAST SIDE. RADAR IS ALREADY SHOWING RETURNS IN
EASTERN SISKIYOU, NORTHERN KLAMATH, AND CENTRAL LAKE COUNTIES.
THERE HAS EVEN BEEN A STRIKE OR TWO RECORDED IN EASTERN SISKIYOU
COUNTY JUST WEST OF TENANT. AND NUMEROUS STRIKES RECORDED JUST
SOUTH OF THE CWA IN LASSEN COUNTY. HI-RES, NEAR TERM MODELS LIKE
THE HRRR (HIGH RESOLUTION RAPID REFRESH) SHOW MOST OF THE ACTION
OVER MODOC, LAKE, AND FAR EASTERN KLAMATH COUNTIES LATER THIS
AFTERNOON. STEERING WINDS ARE FAIRLY LIGHT SO THESE STORMS WILL
LIKELY BE SLOW MOVERS RESULTING IN THE POTENTIAL FOR SOME HEAVIER
DOWNPOURS UNDER THE CORE OF THESE STORMS. ALSO EXPECT SOME GUSTY
OUTFLOW WINDS WITH THE STRONGER STORMS ALONG WITH THE POTENTIAL
FOR SMALL HAIL. MODELS CONTINUE TO SHOW THE ATMOSPHERE STABILIZING
WITH THE LOSS OF DIURNAL HEATING SO CONVECTION SHOULD DIMINISH BY
TONIGHT. THE ATMOSPHERE WEST OF THE CASCADES IS MORE STABLE WITH
WEAKER LAPSE RATES SO NOT EXPECTING ANY THUNDERSTORMS FOR THAT
AREA.
ASIDE FROM THE RAIN EXPECTED WITH THE CONVECTION PREVIOUSLY MENTIONED,
MOST AREAS WILL REMAIN DRY WITH THE PASSAGE OF THE COLD FRONT.
WINDS WILL BE QUITE BREEZY THROUGH THE AFTERNOON IN RESPONSE TO
THIS COLD FRONT MOVING THROUGH THE AREA. THE UPPER LEVEL TROUGH
MOVES THROUGH OVERNIGHT INTO TOMORROW AND DRIER, MORE STABLE AIR
MOVES IN BEHIND IT FOR WEDNESDAY. WEAK RIDGING STARTS TO BUILD
OVER THE AREA WEDNESDAY NIGHT, BUT THIS IS SHORT LIVED AS A WEAK
TROUGH APPROACHES THE AREA THURSDAY MORNING. THERE IS A CHANCE FOR
SOME SHOWERS THURSDAY AFTERNOON, BUT THIS LOOKS MOSTLY CONFINED
FROM THE UMPQUA DIVIDE AND NORTH.
AN UPPER LOW MOVES IN OVER BRITISH COLUMBIA THURSDAY EVENING AND
SHORTWAVES ROTATING AROUND IT CONTINUE THE CHANCE FOR PRECIPITATION
FOR MOST OF THE AREA THROUGH SATURDAY MORNING. MND
LONG TERM...SATURDAY THROUGH TUESDAY...THE OPERATIONAL EC AND
GFS ARE IN SIMILAR AGREEMENT WITH THE OVERALL PATTERN FRIDAY INTO
NEXT WEEKEND. HOWEVER THERE IS DISAGREEMENT WITH THE PLACEMENT AND
STRENGTH OF THE UPPER LOW FRIDAY. THE EC IS STRONGER AND FURTHER
SOUTH WITH THE UPPER LOW AND WETTER. HAVE KEPT IN A CHANCE OF
SHOWERS FOR MOST OF THE FORECAST AREA...THOUGH RAIN AND MOUNTAIN
SNOW AMOUNTS SHOULD BE LIGHT. THE TROUGH AXIS SHIFTS EAST FRIDAY
NIGHT AND RIDGING WILL ATTEMPT TO MOVE IN FROM THE SOUTHWEST. THE
GFS SHOWS MORE OF A DIRTY RIDGE SCENARIO WITH WARM FRONTAL
PRECIPITATION MOVING INTO THE AREA. THE EC HAS A MORE PRONOUNCED
RIDGE AND THUS SHOWS A DRY AND MILDER SOLUTION. SUSPECT THE WARM
FRONTAL PRECIPITATION IS OVERDONE, BUT DID NOT WANT TO DISCOUNT IT
COMPLETELY, SO WITH WITH A BLEND BETWEEN THE EC AND GFS WITH A
SLIGHTLY DRIER BIAS.
A DIRTY RIDGE REMAIN OVER THE AREA SUNDAY WITH THE BEST CHANCE FOR
PRECIPITATION OVER THE NORTHERN PART OF THE CWA. ESPECIALLY WEST OF
THE CASCADES AND NORTH OF THE UMPQUA DIVIDE.
SIGNIFICANT UPPER TROUGHING THAT`S BEEN HANGING OVER THE NORTHEAST
PACIFIC FINALLY REACHES THE FORECAST AREA WITH SIGNIFICANT RAIN
POTENTIALLY MONDAY INTO TUESDAY. THAT SAID...THERE IS SOME
UNCERTAINTY AS TO WHEN THIS TROUGHING REACHES THE AREA. ENSEMBLE
MEMBERS ARE OUT OF PHASE...BUT NOT AS MUCH AS YESTERDAY WITH THE
TROUGH AXIS STARTING TO DROP SOUTH. IN CONTRAST, THE OPERATIONAL EC
SHOWS MORE OF A SPLIT FLOW PATTERN NEAR 150 W AND MORE RIDGING IN
OUR AREA, THUS DELAYING ANY SIGNIFICANT PRECIPITATION.
IN SHORT...CONFIDENCE IS LOW TO MODERATE IN THE EXTENDED PERIOD AND
DID NOT MAKE ANY SIGNIFICANT CHANGES. -PETRUCELLI
.FIRE WEATHER...UPDATED 3 PM PDT TUESDAY, APRIL 21ST, 2015... THE
ATMOSPHERE IS ALREADY STARTING TO BECOME UNSTABLE AHEAD OF A
RATHER SHARP, BUT NOT STRONG, INCOMING TROUGH OF LOW PRESSURE. A
FEW ISOLATED STORMS HAVE DEVELOPED IN NORTHERN CAL AND NORTHERN
KLAMATH COUNTY NORTHEAST OF CHEMULT. THE LATEST HRRR REFLECTIVITY
PRODUCT SHOWS MOST OF THE ACTIVITY DEVELOPING IN NORTHERN CAL,
THEN MIGRATING NORTH INTO PARTS OF LAKE AND KLAMATH COUNTIES LATE
THIS AFTERNOON THROUGH THIS EVENING. UNLIKE THE HIGH IMPACT
LIGHTNING EVENTS THAT SOMETIMES AFFECT OUR REGION MAINLY IN THE
SUMMER, FORCING WITH THE INCOMING SYSTEM IS WEAK IN THAT THERE IS
NO CLEAR COLD POOL MOVING THROUGH. INSTEAD, A WEAK SURFACE FRONT
IS EXPECTED TO DEVELOP ALONG AND NEAR THE CASCADES THIS AFTERNOON.
THIS SHOULD GIVE RISE TO BUILD-UPS ALONG AND NEAR THE TRINITY ALPS
AND CASCADE CREST THIS AFTERNOON, SHIFTING EASTWARD TO THE LEE OF
THE CASCADES TOWARDS THE EVENING. CONDITIONS ARE MOST FAVORABLE
FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN THESE LEE AND
EAST SIDE AREAS. MOST GUIDANCE FOCUSES ACTIVITY THIS EVENING IN
THE WARNER MOUNTAINS OF LAKE COUNTY AND ANOTHER IN NORTHERN LAKE
COUNTY THIS EVENING. WHILE FIRE DANGER DID REACH HIGH IN PORTIONS
OF THE MODOC ON MONDAY, FORECAST FIRE DANGER FOR TODAY IS
MODERATE. ADDITIONALLY, DEPARTURE FROM AVERAGE GREENNESS IS SPOTTY
IN TERMS OF DEFICITS, SO SUSPECT THERE`S SOME GREEN-UP COMPONENT
TO THE LIVE FUELS NOW. MODELS INDICATE THAT ANY STORMS THAT DO GET
GOING WILL PRODUCE GUSTY OUTFLOW WINDS MAINLY IN THE 20 TO 30 MPH
RANGE, BUT ALSO SOME MEASURABLE RAINFALL. THUS, DESPITE UNUSUALLY
DRY CONDITIONS DUE TO THE ONGOING DROUGHT, WE HAVE DECIDED THAT
THIS EVENT DOES NOT WARRANT ANY WARNINGS. INSTEAD, A HEADS-UP TYPE
OF HEADLINE WILL BE MAINTAINED IN THE FORECAST. BTL/PETRUCELLI
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT THURSDAY FOR
PZZ350-356-370-376.
HAZARDOUS SEAS WARNING UNTIL 5 AM PDT THURSDAY FOR PZZ356-376.
GALE WARNING UNTIL 5 AM PDT THURSDAY FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT THURSDAY
FOR PZZ350-356-370-376.
$$
FJB/FJB/FJB
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
942 PM CDT THU APR 23 2015
.DISCUSSION...
COOL HIGH PRESSURE HAS SETTLED OVER THE REGION WITH HIGH CLOUDS
STREAMING IN FROM THE WEST. TEMPS ARE IN THE 50S WITH LIGHT WINDS.
NOT MUCH CHANGE OVERNIGHT. TEMPS WILL FALL A FEW DEGREES AND THE
LATEST HRRR IS BRINGING SOME SHRAS TOWARD THE AREA LATE AS THE
WARM FRONT STARTS LIFTING NORTH. CURRENT FORECAST ON TRACK. NO
CHANGES NEEDED.
SJM
&&
PREV DISCUSSION... /ISSUED 239 PM CDT THU APR 23 2015/
CURRENTLY THE MIDSOUTH WAS PARTLY TO MOSTLY CLOUDY WITH A FEW
SPRINKLES STILL LINGERING ON RADAR ACROSS THE SOUTHERN COUNTIES OF
NORTH MISSISSIPPI. TEMPERATURES WERE IN THE LOW TO MID 60S...WITH
NORTH TO NORTHEAST WINDS RANGING FROM 5 TO 10 KTS. ONLY AN
ADDITIONAL DEGREE OR TWO OF WARMING IS EXPECTED TODAY.
FOR TONIGHT...REDUCED RAIN CHANCES TONIGHT AND KEPT THEM MAINLY
WEST OF THE MISSISSIPPI RIVER AS MODELS HAVE SLOWED THE ONSET OF
A LIFTING WARM FRONT. SKIES HOWEVER WILL REMAIN MOSTLY CLOUDY OVER
MOST OF THE REGION...KEEPING TEMPERATURES A BIT MILDER.
FRIDAY AND SATURDAY...CURRENT TROUGH ACROSS THE SOUTHWEST STATES
IS PROGGED TO ADVANCE NORTHEAST TO THE MID MISSISSIPPI VALLEY...
WHILE A SURFACE LOW IN WESTERN KANSAS TRACKS TO THE OHIO RIVER.
THIS SYSTEM IS FORECASTED TO UNDERGO DEEPENING INITIALLY FRIDAY
AND FRIDAY NIGHT...AND THEN MAINTAIN STEADY STRENGTH ON SATURDAY.
A WARM FRONT WILL LIFT NORTH THROUGH THE MIDSOUTH WITH THE THREAT
FOR SHOWERS AND STORMS INCREASING THROUGHOUT THE DAY. BEST CHANCES
FOR RAIN THOUGH WILL ARRIVE FRIDAY EVENING WITH EMBEDDED ELEVATED
THUNDER. QUESTIONS ARISE AFTER MIDNIGHT IF STORMS CAN REFORM NEAR
THE BOUNDARY OR IN THE WARM SECTOR. INSTABILITY APPEARS WEAK BUT
SHEAR IS STRONG. SO AN ISOLATED LARGE HAIL OR DAMAGING WIND REPORT
COULD MATERIALIZE...ESPECIALLY ACROSS THE WEST. BY MID MORNING
SATURDAY A SURGING DRY SLOT WILL BEGIN SHOVING THE LOW LEVEL
MOISTURE INTO MIDDLE TENNESSEE AND NORTHERN ALABAMA. THE MIDSOUTH
COUNTIES WILL HAVE A SMALL WINDOW FOR SEVERE WEATHER AROUND MIDDAY.
THESE STORMS WOULD HAVE A BETTER POTENTIAL FOR LARGE HAIL AND
DAMAGING WINDS AS CAPE CLIMBS TO NEAR 2500 J/KG AND LI`S DROP TO
-9C. UNLESS THE SYSTEM SLOWS CONSIDERABLY THE BEST THREAT ON
SATURDAY WILL BE EAST OF THE MEMPHIS METRO. THE DRY SLOT WILL
PROVIDE FOR GUSTY WINDS...WITH THE STRONG MIXING PROVIDING HIGHS
IN THE 80S. THE DELTA COUNTIES MAY NEED A WIND ADVISORY SATURDAY
AFTERNOON. A WEAK COLD FRONT WILL PASS THROUGH THE MIDSOUTH
SATURDAY NIGHT...BUT LIFT FROM THIS FEATURE WILL BE WEAK WITH ONLY
A FEW STRAY SHOWERS POSSIBLE.
SUNDAY AND SUNDAY NIGHT...SURFACE HIGH PRESSURE WILL BRIEFLY
BUILD INTO THE REGION WITH DRY WEATHER AND MILDER HIGHS.
MONDAY THROUGH WEDNESDAY...A SECOND TROUGH/CLOSED LOW WILL TRACK
ACROSS THE SOUTHERN U.S. THE EURO AND GFS ARE BIT BETTER ALIGNED
ON STORM STRENGTH AND TRACK...WITH THE GFS STILL REMAINING A BIT
FASTER WITH TIMING. A COASTAL SURFACE LOW IS ANTICIPATED TO FORM
AHEAD OF THE UPPER LOW. MOISTURE WILL RETURN TO THE MIDSOUTH WITH
A PERSISTENT LOW LEVEL NORTH TO NORTHEAST FLOW...A MORE WINTER
LIKE PATTERN. CLOUDS AND PERIODS OF RAIN WITH BELOW NORMAL
TEMPERATURES ARE EXPECTED.
JAB
.AVIATION...
00Z TAF CYCLE
VFR CONDITIONS WILL PERSIST FOR MUCH OF THE FORECAST PERIOD.
CEILINGS WILL LOWER TO IFR LEVELS AT KJBR AND MVFR LEVELS AT KMEM
LATE FRIDAY AFTERNOON. SHOWERS AND ISOLATED THUNDERSTORMS WILL
START TO MOVE INTO WESTERN SECTIONS OF THE FORECAST AREA BY LATE
FRIDAY MORNING AND CONTINUE TO MOVE EAST DURING THE AFTERNOON
HOURS. WINDS WILL BE MAINLY FROM THE SOUTHEAST AT 5 TO 10 KNOTS
FOR MUCH OF THE FORECAST PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1012 AM CDT WED APR 22 2015
.UPDATE...
BUMPED TEMPERATURES UP SLIGHTLY BASED ON CLOUD COVER AND
TEMPERATURE TRENDS. HIGHS SHOULD INTO THE 70S ACROSS MOST OF THE
AREA...PERHAPS TO NEAR 80 IN THE WARMEST LOCATIONS IN NORTH
MISSISSIPPI. SOME SHOWERS AND THUNDERSTORMS CAN BE SEEN ON RADAR
IN EAST OKLAHOMA AND WEST ARKANSAS. THEY ARE EXPECTED TO MOVE
TOWARD THE MIDSOUTH...BUT WEAKEN AS THEY APPROACH. LOWERED POPS
BEFORE NOON. AFTER NOON...AS TEMPERATURES WARM AND SHOWERS
APPROACH FROM THE WEST ANY LOCATION ACROSS THE MIDSOUTH COULD SEE
A SHOWER OR PERHAPS AN ISOLATED THUNDERSTORM.
&&
.PREV DISCUSSION... /ISSUED 637 AM CDT WED APR 22 2015/
DISCUSSION...09Z SURFACE ANALYSIS PLACES A COLD FRONT FROM
SOUTHEAST MISSOURI BACK THROUGH NORTHWEST ARKANSAS AND NORTHEAST
OKLAHOMA. WSR-88D RADAR TRENDS SHOW A WEAKENING LINE OF SHOWERS
BEGINNING TO ENTER PORTIONS OF NORTHEAST ARKANSAS AND THE MISSOURI
BOOTHEEL. AS OF 4 AM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE
PREDOMINANTLY IN THE LOWER TO MIDDLE 50S AT MOST LOCATIONS. STRONG
TO SEVERE THUNDERSTORM POTENTIAL IN THE SHORT TERM IS THE MAIN
CONCERN IN THIS MORNING/S FORECAST ISSUANCE.
SHORT TERM...(TODAY THROUGH FRIDAY)...A COLD FRONT WILL DROP INTO
THE MID SOUTH TODAY. LATEST SHORT TERM MODELS/MODEL SOUNDINGS
INCLUDING THE HRRR SUGGEST AN AREA OF SHOWERS WILL WEAKEN AND
DISSIPATE AS IT MOVES INTO THE MID SOUTH THIS MORNING. HAVE
INCLUDED LOW END CHANCE POPS ACROSS PORTIONS OF NORTHEAST ARKANSAS
THIS MORNING AND ISOLATED POPS ACROSS THE REMAINDER OF THE
FORECAST AREA NORTH OF I-40. SOME SURFACE BASED INSTABILITY WILL
BE PRESENT MAINLY SOUTH OF I-40 AND HAVE INCLUDED ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE MID SOUTH THIS AFTERNOON.
WRF/GFS/ECMWF MODELS INDICATE A MESOSCALE CONVECTIVE SYSTEM /MCS/
MAY DEVELOP OVER THE RED RIVER VALLEY THIS AFTERNOON AND MOVE EAST
SOUTHEAST INTO THE LOWER MISSISSIPPI VALLEY TONIGHT. AT THIS
TIME...THINK A BULK OF THIS ACTIVITY WILL REMAIN MOSTLY TO THE
SOUTH OF THE FORECAST AREA TONIGHT WITH THE BEST SHOWER AND
THUNDERSTORM CHANCES MAINLY ACROSS THE SOUTHERN TIER OF COUNTIES
ACROSS NORTHWEST MISSISSIPPI AND CHANCE POPS ACROSS THE REMAINDER
OF NORTH MISSISSIPPI TONIGHT INTO THURSDAY MORNING.
SHOWER AND THUNDERSTORM CHANCES WILL DECREASE ACROSS MOST OF THE
AREA THURSDAY AFTERNOON AS SHORTWAVE RIDGING BUILDS IN ACROSS THE
MID SOUTH INTO THURSDAY EVENING. THE COLD FRONT TO THE SOUTH OF
THE AREA IS EXPECTED TO BEGIN MOVING BACK NORTH AS WARM FRONT
LATE THURSDAY NIGHT INTO FRIDAY WITH SHOWERS AND THUNDERSTORMS
RETURNING ONCE AGAIN.
INCREASING SURFACE BASED INSTABILITY TO PERHAPS AROUND 1500
J/KG...0-6 KM BULK SHEAR VALUES AVERAGING AROUND 50-55 KTS...0-1
KM STORM RELATIVE HELICITY VALUES BETWEEN 200-300 M2/S2...FAVORABLE
WINDS ALOFT AND BACKED SURFACE WINDS SUGGEST POSSIBLE MCS
DEVELOPMENT ACROSS THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY AND A SUBSEQUENT POTENTIAL FOR SEVERE THUNDERSTORMS FRIDAY
INTO FRIDAY NIGHT. LARGE HAIL...DAMAGING WINDS...AND PERHAPS A
POTENTIAL FOR TORNADOES ARE THE POTENTIAL SEVERE THUNDERSTORM
THREATS. AS OF THIS MORNING...THE SPC DAY THREE OUTLOOK CURRENTLY
COVERS PORTIONS OF EAST/NORTHEAST ARKANSAS...NORTHWEST MISSISSIPPI
AND FAR SOUTHWEST TENNESSEE AHEAD OF AN APPROACHING COLD FRONT. A
WARM...VERY UNSTABLE AIRMASS WILL BE IN PLACE SATURDAY AS
TEMPERATURES RISE INTO THE UPPER 70S TO LOWER 80S. AT THIS
TIME...IT APPEARS THAT SEVERE THUNDERSTORMS ARE AGAIN POSSIBLE
ON SATURDAY. IN ADDITION TO THE SEVERE THUNDERSTORM THREAT
FRIDAY AND SATURDAY...HIGH PRECIPITABLE WATER VALUES SUGGEST A
POTENTIAL FOR HEAVY RAINFALL DURING THIS TIME FRAME. WILL INCLUDE
MENTION OF THREATS IN THE HAZARDOUS WEATHER OUTLOOK AND LATER
SHIFTS WILL ADJUST POSSIBLE THREATS IN SUBSEQUENT MODEL RUNS. STAY
TUNED...
LONG TERM...(SATURDAY NIGHT THROUGH TUESDAY)...00Z GFS/ECMWF
LONG RANGE MODELS ARE IN DECENT AGREEMENT ON SATURDAY BUT DIVERGE
THEREAFTER AS EVIDENT IN EACH LONG RANGE MODEL/S RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO RESOLVE A SPLIT FLOW REGIME ACROSS
THE CONTINENTAL UNITED STATES. THUS...HAVE LEANED POPS TOWARDS
LOWER CONFIDENCE THROUGH MUCH OF THE FORECAST BEYOND SATURDAY.
CJC
&&
.AVIATION...12Z TAFS
VFR WILL PREVAIL THROUGH THE DAY...AS A REINFORCING PUSH OF
RELATIVELY DRY MIDCONTINENTAL AIR FLOWS INTO THE REGION BEHIND A
WEAK COLD FRONT THIS MORNING. SMALL PATCH OF POST FRONTAL MVFR
CIGS OVER KY SHOULD PASS TO THE EAST OF MKL...BUT WILL NEED TO
MONITORED IN THE SHORT TERM.
EXTENSIVE MIDLEVEL MOISTURE WILL SPREAD OVER THE ELEVATED FRONTAL
SURFACE THIS EVENING. NAM BUFR SOUNDINGS DRY LAYER AT MEM DECREASING
IN DEPTH FROM FL100 AROUND THE TIME OF THE CARGO ARRIVAL PUSH...TO
FL060 NEAR THE END OF THE VALID TAF PERIOD. PERSISTENT ELEVATED
RAINFALL MAY BE SUFFICIENT DROP CIGS INTO THE HIGH MVFR CAT AT TUP
DURING THE LATE OVERNIGHT.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
637 AM CDT WED APR 22 2015
.UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 515 AM CDT WED APR 22 2015/
DISCUSSION...09Z SURFACE ANALYSIS PLACES A COLD FRONT FROM
SOUTHEAST MISSOURI BACK THROUGH NORTHWEST ARKANSAS AND NORTHEAST
OKLAHOMA. WSR-88D RADAR TRENDS SHOW A WEAKENING LINE OF SHOWERS
BEGINNING TO ENTER PORTIONS OF NORTHEAST ARKANSAS AND THE MISSOURI
BOOTHEEL. AS OF 4 AM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE
PREDOMINANTLY IN THE LOWER TO MIDDLE 50S AT MOST LOCATIONS. STRONG
TO SEVERE THUNDERSTORM POTENTIAL IN THE SHORT TERM IS THE MAIN
CONCERN IN THIS MORNING/S FORECAST ISSUANCE.
SHORT TERM...(TODAY THROUGH FRIDAY)...A COLD FRONT WILL DROP INTO
THE MID SOUTH TODAY. LATEST SHORT TERM MODELS/MODEL SOUNDINGS
INCLUDING THE HRRR SUGGEST AN AREA OF SHOWERS WILL WEAKEN AND
DISSIPATE AS IT MOVES INTO THE MID SOUTH THIS MORNING. HAVE
INCLUDED LOW END CHANCE POPS ACROSS PORTIONS OF NORTHEAST ARKANSAS
THIS MORNING AND ISOLATED POPS ACROSS THE REMAINDER OF THE
FORECAST AREA NORTH OF I-40. SOME SURFACE BASED INSTABILITY WILL
BE PRESENT MAINLY SOUTH OF I-40 AND HAVE INCLUDED ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE MID SOUTH THIS AFTERNOON.
WRF/GFS/ECMWF MODELS INDICATE A MESOSCALE CONVECTIVE SYSTEM /MCS/
MAY DEVELOP OVER THE RED RIVER VALLEY THIS AFTERNOON AND MOVE EAST
SOUTHEAST INTO THE LOWER MISSISSIPPI VALLEY TONIGHT. AT THIS
TIME...THINK A BULK OF THIS ACTIVITY WILL REMAIN MOSTLY TO THE
SOUTH OF THE FORECAST AREA TONIGHT WITH THE BEST SHOWER AND
THUNDERSTORM CHANCES MAINLY ACROSS THE SOUTHERN TIER OF COUNTIES
ACROSS NORTHWEST MISSISSIPPI AND CHANCE POPS ACROSS THE REMAINDER
OF NORTH MISSISSIPPI TONIGHT INTO THURSDAY MORNING.
SHOWER AND THUNDERSTORM CHANCES WILL DECREASE ACROSS MOST OF THE
AREA THURSDAY AFTERNOON AS SHORTWAVE RIDGING BUILDS IN ACROSS THE
MID SOUTH INTO THURSDAY EVENING. THE COLD FRONT TO THE SOUTH OF
THE AREA IS EXPECTED TO BEGIN MOVING BACK NORTH AS WARM FRONT
LATE THURSDAY NIGHT INTO FRIDAY WITH SHOWERS AND THUNDERSTORMS
RETURNING ONCE AGAIN.
INCREASING SURFACE BASED INSTABILITY TO PERHAPS AROUND 1500
J/KG...0-6 KM BULK SHEAR VALUES AVERAGING AROUND 50-55 KTS...0-1
KM STORM RELATIVE HELICITY VALUES BETWEEN 200-300 M2/S2...FAVORABLE
WINDS ALOFT AND BACKED SURFACE WINDS SUGGEST POSSIBLE MCS
DEVELOPMENT ACROSS THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY AND A SUBSEQUENT POTENTIAL FOR SEVERE THUNDERSTORMS FRIDAY
INTO FRIDAY NIGHT. LARGE HAIL...DAMAGING WINDS...AND PERHAPS A
POTENTIAL FOR TORNADOES ARE THE POTENTIAL SEVERE THUNDERSTORM
THREATS. AS OF THIS MORNING...THE SPC DAY THREE OUTLOOK CURRENTLY
COVERS PORTIONS OF EAST/NORTHEAST ARKANSAS...NORTHWEST MISSISSIPPI
AND FAR SOUTHWEST TENNESSEE AHEAD OF AN APPROACHING COLD FRONT. A
WARM...VERY UNSTABLE AIRMASS WILL BE IN PLACE SATURDAY AS
TEMPERATURES RISE INTO THE UPPER 70S TO LOWER 80S. AT THIS
TIME...IT APPEARS THAT SEVERE THUNDERSTORMS ARE AGAIN POSSIBLE
ON SATURDAY. IN ADDITION TO THE SEVERE THUNDERSTORM THREAT
FRIDAY AND SATURDAY...HIGH PRECIPITABLE WATER VALUES SUGGEST A
POTENTIAL FOR HEAVY RAINFALL DURING THIS TIME FRAME. WILL INCLUDE
MENTION OF THREATS IN THE HAZARDOUS WEATHER OUTLOOK AND LATER
SHIFTS WILL ADJUST POSSIBLE THREATS IN SUBSEQUENT MODEL RUNS. STAY
TUNED...
LONG TERM...(SATURDAY NIGHT THROUGH TUESDAY)...00Z GFS/ECMWF
LONG RANGE MODELS ARE IN DECENT AGREEMENT ON SATURDAY BUT DIVERGE
THEREAFTER AS EVIDENT IN EACH LONG RANGE MODEL/S RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO RESOLVE A SPLIT FLOW REGIME ACROSS
THE CONTINENTAL UNITED STATES. THUS...HAVE LEANED POPS TOWARDS
LOWER CONFIDENCE THROUGH MUCH OF THE FORECAST BEYOND SATURDAY.
CJC
&&
.AVIATION...
12Z TAFS
VFR WILL PREVAIL THROUGH THE DAY...AS A REINFORCING PUSH OF
RELATIVELY DRY MIDCONTINENTAL AIR FLOWS INTO THE REGION BEHIND A
WEAK COLD FRONT THIS MORNING. SMALL PATCH OF POST FRONTAL MVFR
CIGS OVER KY SHOULD PASS TO THE EAST OF MKL...BUT WILL NEED TO
MONITORED IN THE SHORT TERM.
EXTENSIVE MIDLEVEL MOISTURE WILL SPREAD OVER THE ELEVATED FRONTAL
SURFACE THIS EVENING. NAM BUFR SOUNDINGS DRY LAYER AT MEM DECREASING
IN DEPTH FROM FL100 AROUND THE TIME OF THE CARGO ARRIVAL PUSH...TO
FL060 NEAR THE END OF THE VALID TAF PERIOD. PERSISTENT ELEVATED
RAINFALL MAY BE SUFFICIENT DROP CIGS INTO THE HIGH MVFR CAT AT TUP
DURING THE LATE OVERNIGHT.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
515 AM CDT WED APR 22 2015
.DISCUSSION...09Z SURFACE ANALYSIS PLACES A COLD FRONT FROM
SOUTHEAST MISSOURI BACK THROUGH NORTHWEST ARKANSAS AND NORTHEAST
OKLAHOMA. WSR-88D RADAR TRENDS SHOW A WEAKENING LINE OF SHOWERS
BEGINNING TO ENTER PORTIONS OF NORTHEAST ARKANSAS AND THE MISSOURI
BOOTHEEL. AS OF 4 AM CDT...TEMPERATURES ACROSS THE MID SOUTH ARE
PREDOMINANTLY IN THE LOWER TO MIDDLE 50S AT MOST LOCATIONS. STRONG
TO SEVERE THUNDERSTORM POTENTIAL IN THE SHORT TERM IS THE MAIN
CONCERN IN THIS MORNING/S FORECAST ISSUANCE.
.SHORT TERM...(TODAY THROUGH FRIDAY)...A COLD FRONT WILL DROP INTO
THE MID SOUTH TODAY. LATEST SHORT TERM MODELS/MODEL SOUNDINGS
INCLUDING THE HRRR SUGGEST AN AREA OF SHOWERS WILL WEAKEN AND
DISSIPATE AS IT MOVES INTO THE MID SOUTH THIS MORNING. HAVE
INCLUDED LOW END CHANCE POPS ACROSS PORTIONS OF NORTHEAST ARKANSAS
THIS MORNING AND ISOLATED POPS ACROSS THE REMAINDER OF THE
FORECAST AREA NORTH OF I-40. SOME SURFACE BASED INSTABILITY WILL
BE PRESENT MAINLY SOUTH OF I-40 AND HAVE INCLUDED ISOLATED SHOWERS
AND THUNDERSTORMS ACROSS THE MID SOUTH THIS AFTERNOON.
WRF/GFS/ECMWF MODELS INDICATE A MESOSCALE CONVECTIVE SYSTEM /MCS/
MAY DEVELOP OVER THE RED RIVER VALLEY THIS AFTERNOON AND MOVE EAST
SOUTHEAST INTO THE LOWER MISSISSIPPI VALLEY TONIGHT. AT THIS
TIME...THINK A BULK OF THIS ACTIVITY WILL REMAIN MOSTLY TO THE
SOUTH OF THE FORECAST AREA TONIGHT WITH THE BEST SHOWER AND
THUNDERSTORM CHANCES MAINLY ACROSS THE SOUTHERN TIER OF COUNTIES
ACROSS NORTHWEST MISSISSIPPI AND CHANCE POPS ACROSS THE REMAINDER
OF NORTH MISSISSIPPI TONIGHT INTO THURSDAY MORNING.
SHOWER AND THUNDERSTORM CHANCES WILL DECREASE ACROSS MOST OF THE
AREA THURSDAY AFTERNOON AS SHORTWAVE RIDGING BUILDS IN ACROSS THE
MID SOUTH INTO THURSDAY EVENING. THE COLD FRONT TO THE SOUTH OF
THE AREA IS EXPECTED TO BEGIN MOVING BACK NORTH AS WARM FRONT
LATE THURSDAY NIGHT INTO FRIDAY WITH SHOWERS AND THUNDERSTORMS
RETURNING ONCE AGAIN.
INCREASING SURFACE BASED INSTABILITY TO PERHAPS AROUND 1500
J/KG...0-6 KM BULK SHEAR VALUES AVERAGING AROUND 50-55 KTS...0-1
KM STORM RELATIVE HELICITY VALUES BETWEEN 200-300 M2/S2...FAVORABLE
WINDS ALOFT AND BACKED SURFACE WINDS SUGGEST POSSIBLE MCS
DEVELOPMENT ACROSS THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY AND A SUBSEQUENT POTENTIAL FOR SEVERE THUNDERSTORMS FRIDAY
INTO FRIDAY NIGHT. LARGE HAIL...DAMAGING WINDS...AND PERHAPS A
POTENTIAL FOR TORNADOES ARE THE POTENTIAL SEVERE THUNDERSTORM
THREATS. AS OF THIS MORNING...THE SPC DAY THREE OUTLOOK CURRENTLY
COVERS PORTIONS OF EAST/NORTHEAST ARKANSAS...NORTHWEST MISSISSIPPI
AND FAR SOUTHWEST TENNESSEE AHEAD OF AN APPROACHING COLD FRONT. A
WARM...VERY UNSTABLE AIRMASS WILL BE IN PLACE SATURDAY AS
TEMPERATURES RISE INTO THE UPPER 70S TO LOWER 80S. AT THIS
TIME...IT APPEARS THAT SEVERE THUNDERSTORMS ARE AGAIN POSSIBLE
ON SATURDAY. IN ADDITION TO THE SEVERE THUNDERSTORM THREAT
FRIDAY AND SATURDAY...HIGH PRECIPITABLE WATER VALUES SUGGEST A
POTENTIAL FOR HEAVY RAINFALL DURING THIS TIME FRAME. WILL INCLUDE
MENTION OF THREATS IN THE HAZARDOUS WEATHER OUTLOOK AND LATER
SHIFTS WILL ADJUST POSSIBLE THREATS IN SUBSEQUENT MODEL RUNS. STAY
TUNED...
.LONG TERM...(SATURDAY NIGHT THROUGH TUESDAY)...00Z GFS/ECMWF
LONG RANGE MODELS ARE IN DECENT AGREEMENT ON SATURDAY BUT DIVERGE
THEREAFTER AS EVIDENT IN EACH LONG RANGE MODEL/S RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO RESOLVE A SPLIT FLOW REGIME ACROSS
THE CONTINENTAL UNITED STATES. THUS...HAVE LEANED POPS TOWARDS
LOWER CONFIDENCE THROUGH MUCH OF THE FORECAST BEYOND SATURDAY.
CJC
&&
.AVIATION...
06Z TAFS
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. AREA OF
SHRAS AHEAD OF AN APPROACHING COLD FRONT MOVING ACROSS NORTHERN
SECTIONS OF THE MIDSOUTH ATTM. THE ASSOCIATED WEAK GUST FRONT
WILL BRIEFLY TURN WINDS NWLY AT MKL WITH PERHAPS A SHRA ON
STATION. REMAINDER OF NIGHT WILL FEATURE SSW WINDS AROUND 10 KTS
AT KMEM...KJBR AND KMKL...LIGHTER AT KTUP. COLD FRONT WILL MOVE
THROUGH ON MONDAY. A FEW SHRA ARE POSSIBLE AT KJBR AND KMKL BUT
NOT WORTHY OF VCSH YET. OTRW WINDS WILL SHIFT AROUND TO THE NW/N
AT 10 KTS. SHRAS AND SOME LOWER CLOUDS WILL BEGIN APPROACHING FROM
THE WEST TOWARD THE END OF THE PERIOD AND ADDED A VCSH AND A
BKN050 DECK AT KJBR/KMEM AROUND 23/05Z.
SJM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
402 PM CDT WED APR 22 2015
.DISCUSSION...
UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY STILL SHOW A RATHER
PERSISTENT SOUTHERN JET STREAM OVER MUCH OF TX. IT IS HARD TO
IDENTIFY BUT IT APPEARS THAT THE CONVECTION OVER THE COASTAL BEND
AND NOW EAST OF SAN ANTONIO MAY BE SUPPORTED BY A WEAK SHORTWAVE
TROUGH. OVERALL PATTERN SHOWS WEAK SHORT WAVE RIDGING BUT THIS
DISTURBANCE MAY BE FLATTENING OUT THE RIDGE A BIT TODAY.
THERMODYNAMIC AND SHEAR PARAMETERS SUPPORT THE THREAT FOR SEVERE
STORMS WITH SOME STORMS BECOMING ORGANIZED. SHEAR WILL SUPPORT
STORM ROTATION AND LOW LEVEL TURNING OF THE WINDS WITH A
DEVELOPING WARM FRONT MAY BE ENOUGH TO SUPPORT LOW LEVEL ROTATION
IN STORMS ESPECIALLY ALONG THE COASTAL BEND. RECENT RAP/HRRR MODEL
RUNS BRING CONVECTION EAST OF KSAT INTO SE TX AROUND 23-01Z.
MODELS SHOW THAT STORMS MAY BE WEAKENING BUT COULD BE MOVING INTO
A MORE FAVORABLE ENVIRONMENT GIVEN TRENDS IN HEATING/INSTABILITY.
MODELS ALSO SHOW CONVECTION ALONG A BOUNDARY STRETCHING NW/SE FROM
MINERAL WELLS TO LUFKIN. THIS HIGHLIGHTS THE SEVERE THREAT FOR THE
NORTHERN MOST COUNTIES IN THE FORECAST AREA MAINLY
MADISON...HOUSTON...TRINITY CO. THE IDEA IS FOR THE THREAT TO END
LATER TONIGHT BUT HRRR TRENDS SHOW CONVECTION COMING DOWN FROM
THE METROPLEX AND AFFECT THE AREAS FROM COLLEGE STATION TO
HUNTSVILLE OVER THE LIVINGSTON BY EARLY MORNING HOURS. SO IT
APPEARS THERE WILL BE AT LEAST SOME OVERNIGHT THREAT.
THURSDAY LOOKS A BIT MORE QUIET AS MODELS DO AMPLIFY RIDGING OVER
THE REGION ALTHOUGH THERE WILL BE PLENTY OF MOISTURE/INSTABILITY
TO SUPPORT SEVERE STORMS. WE DO NOT WANT TO BE COMPLACENT BUT
THINK 20/30 POPS MIGHT BE GENEROUS. MOVING AHEAD TO
FRIDAY...RIDGING MOVES EAST IN RESPONSE TO UPPER LEVEL TROUGH OVER
THE S ROCKIES PUSHING INTO THE TX PANHANDLE AND S PLAINS. SFC LOW
DEEPENS AND MOVES INTO THE C PLAINS IN RESPONSE WITH STRONG JET
STREAK FROM MIDLAND TO OKC. THIS PUTS SE TX ON A MORE SUBSIDENT
SIDE OF THE JET BUT THAT MAY NOT MATTER MUCH WITH THE CURVATURE OF
THE JET. THERE IS ALSO A PACIFIC FRONT THAT DEVELOPS WITH
CONVECTION FORMING IN C TX MOVING EAST. THIS WILL AGAIN PUT AREAS
NORTH OF I-10 IN A THREAT FOR SEVERE WEATHER SINCE THERE WILL
AGAIN BE PLENTY OF MOISTURE/INSTABILITY AND SHEAR. MAIN QUESTION
WILL BE CAP STRENGTH. 850MB WINDS VEER TO SW WITH TEMPS AROUND 20C
OR MORE FOR MUCH OF THE SOUTHERN HALF OF THE AREA. AGAIN THIS
SUPPORTS IDEA OF AREAS NORTH OF I-10 OR EVEN NORTH OF CONROE WILL
HAVE A HIGHER THREAT FOR SEVERE WEATHER FRIDAY.
WE CONTINUE THUNDERSTORM CHANCES SATURDAY AS THE THROUGH PASSES NE
OF THE AREA OVERNIGHT. SOUTHERN JET STILL IS STRONG OVER THE
REGION. PACIFIC FRONT STALLS OVER THE AREA WHICH COULD SUPPORT A
FEW STORMS BUT WITH 850MB FLOW BECOMING MORE WSW...THINK STORMS
WILL BE ISO IN NATURE. WITH THE VEERED BOUNDARY LAYER FLOW...MAX
TEMPS COULD REACH UPPER 80S TO 90F BOTH SAT/SUN.
WHILE THERE MAY BE A BREAK FROM SEVERE WEATHER OVER THE
WEEKEND...MONDAY COULD BE ACTIVE AGAIN. BOTH GFS/ECMWF BRING A
UPPER LOW INTO THE PLAINS DURING THE DAY MON WITH FAVORABLE
SPLITTING JET STRUCTURE. LARGE SCALE ASCENT WILL BE STRONG ENOUGH
TO ERODE ANY CAPPING LEADING TO A MID MORNING TO EARLY AFTERNOON
SEVERE WEATHER CHANCES. DRYLINE/PACIFIC FRONT PUSHES THROUGH MON
NIGHT INTO TUE AS THUNDERSTORM ACTIVITY MOVES EAST. A STRONGER
COLD FRONT PUSHES THROUGH TUESDAY WHICH MUCH COLDER AIR BEHIND IT.
IN FACT THE 850MB TEMPS DROP TO ANYWHERE BETWEEN 4C AND 8C TUE
NIGHT INTO WED DEPENDING ON THE MODEL. SO IT LOOKS LIKE MONDAY
WILL NEED TO BE WATCHED CLOSELY FOR DETAILS ON SEVERE WEATHER BUT
GOOD NEWS THAT THERE COULD BE A STRONG COLD FRONT TO PUSH THROUGH
ONE LAST TIME BEFORE HEADING INTO THE MONTH OF MAY.
39
&&
.MARINE...
AS HIGH PRESSURE LINGERS TO THE EAST AND PRESSURES FALL OVER THE SRN
PLAINS...THE LIGHT/MODERATE ONSHORE FLOW WILL BE CONTINUING OVER THE
UPPER TX COAST THROUGH THE END OF THE WEEK/INTO THE WEEKEND. STRONG-
ER GUSTS/LIMITED VISIBILITIES POSSIBLE WITH STORMS DEVELOPING ACROSS
THE COASTAL WATERS THE REST OF THIS AFTN/EVENING...WITH LATER ROUNDS
OF PCPN POSSIBLE THURS AND FRI. LONG-RANGE MODELS STILL GOING WITH A
STRONG COLD FRONT INTO THE GULF WATERS NEXT TUES. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 70 85 71 83 68 / 40 30 30 60 20
HOUSTON (IAH) 69 86 73 84 71 / 20 20 20 40 20
GALVESTON (GLS) 72 82 73 82 73 / 20 20 20 30 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...41
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
231 PM CDT WED APR 22 2015
.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
SEMI ACTIVE WEATHER PATTERN FOR THE NEXT FEW DAYS FOLLOWED BY A
FRONT THIS WEEKEND THEN DRYING OUT EARLY NEXT WEEK.
AS OF 2 PM THERE IS A MULTICELL CLUSTER OF THUNDERSTORMS
APPROACHING BEXAR COUNTY AND SAN ANTONIO. THE HRRR TAKES THIS
COMPLEX AS WELL AS OTHER SHOWERS AND THUNDERSTORMS OUT AHEAD OF IT
EASTWARD IMPACTING A BASTROP SOUTH TO GONZALES AND KENEDY LINE.
MODEL SOUNDINGS FROM THE NAM SHOW AN UNCAPPED ATMOSPHERE ALONG
AND EAST OF I-35 THIS AFTERNOON WITH 1000-3000 J/KG OF CAPE AND
50-60 KNOTS OF SHEAR. THIS MEANS THAT THIS COMPLEX OF STORMS IS
MOVING INTO A VERY GOOD ENVIRONMENT FOR STRONG TO SEVERE STORMS.
WE CONTINUE UNDER A SLIGHT RISK FROM SPC THIS AFTERNOON ALONG AND
EAST OF US HWY 281. WE HAVE ALSO SEEN HEAVY RAINFALL RATES OUT OF
THE ONGOING STORMS SO SOME LOCALIZED FLOODING IS NOT OUT OF THE
QUESTION WITH THE STRONGER STORMS. THE MAIN THREATS WILL BE LARGE
HAIL AND DAMAGING WINDS WITH ANY SEVERE WEATHER THAT DOES OCCUR
THIS AFTERNOON AND EVENING. THE THREAT FOR TORNADOES REMAINS LOW
AS LOW LEVEL SHEAR IS WEAK.
OTHER FEATURES IN PLAY TODAY ARE A STATIONARY FRONT ACROSS THE
RED RIVER IN NORTH TEXAS AND THE DRYLINE OUT IN WEST
TEXAS...ALTHOUGH OTHER THAN AN ISOLATED DRYLINE STORM NEITHER WILL
IMPACT OUR WEATHER MUCH. GENERAL RIDGING IS FORECAST TO TAKE
PLACE THROUGH THE PERIOD AS HIGH PRESSURE OVER NORTHERN MEXICO
MOVES SLOWLY EAST. CONVECTION WILL DECREASE OVERNIGHT TONIGHT AND
WITH NORTHWEST FLOW CONTINUING ONLY SLIGHT CHANCES FOR
PRECIPITATION ARE FORECAST FOR THURSDAY THROUGH THURSDAY EVENING.
MODEL SOUNDINGS SHOW A STRONG CAP ACROSS MOST OF SOUTH CENTRAL
TEXAS DURING THE DAY TOMORROW. BY LATE IN THE AFTERNOON MODELS DO
WEAKEN THE CAP WHICH COULD ALLOW FOR SOME ISOLATED SHOWERS AND
THUNDERSTORMS. AGAIN...CONDITIONS WILL BE FAVORABLE TOMORROW FOR
SEVERE WEATHER WITH 50 KNOTS OF UPPER LEVEL SHEAR AND 2000-3000
J/KG OF CAPE. THE DAY 2 OUTLOOK FROM SPC HAS THE WHOLE AREA IN A
SLIGHT RISK FOR TOMORROW...WITH LARGE HAIL AND DAMAGING WINDS
AGAIN THE PRIMARY THREATS.
&&
.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
MODELS ARE IN AGREEMENT THAT THURSDAY NIGHT THROUGH FRIDAY MORNING
WILL BE A PERIOD OF HIGHER QPF...HIGHER RAIN CHANCES. THE GREATEST
CHANCES FOR RAIN WILL BE ALONG THE RIO GRANDE PLAINS THURSDAY
NIGHT SPREADING TO AREAS ALONG AND EAST OF I-35 FOR FRIDAY. AN
UPPER LEVEL TROUGH APPROACHING FROM THE WEST WILL PROVIDE THE
NEEDED LIFT FOR THIS PRECIPITATION. CHANCES OF SEVERE WEATHER
CONTINUE INTO FRIDAY WITH THE BEST INSTABILITY LOCATED ALONG AND
WEST OF I-35. AS THE TROUGH MOVES OFF TO THE EAST AND NORTHEAST
SATURDAY CHANCES FOR RAIN WILL DECREASE THROUGH THE DAY. THE NEXT
FRONT WILL MOVE THROUGH SUNDAY INTO MONDAY. THE GFS AND NEW 12Z
ECMWF DISAGREE BY ABOUT 24 ON THE TIMING OF THIS FRONT...WITH THE
ECMWF BRING THE SLOWER OF THE TWO. WILL GO WITH A PERSISTENCE
FORECAST AND CHANCE POPS FOR SUNDAY AND MONDAY...DRYING OUT
TUESDAY. THE ONE BENEFIT OF THIS FRONT IS IT WILL COOL THE AREA
BACK DOWN INTO THE 70S FOR HIGHS FOR A FEW DAYS BY THE MIDDLE OF
NEXT WEEK.
TREADWAY
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 70 88 70 85 67 / 30 30 40 60 30
AUSTIN BERGSTROM INTL AIRPORT 69 87 70 84 66 / 30 30 40 50 30
NEW BRAUNFELS MUNI AIRPORT 69 88 71 85 67 / 20 20 40 50 40
BURNET MUNI AIRPORT 67 87 68 84 64 / 30 40 40 60 20
DEL RIO INTL AIRPORT 69 90 68 88 64 / 10 20 50 30 30
GEORGETOWN MUNI AIRPORT 69 87 70 84 65 / 30 40 40 60 20
HONDO MUNI AIRPORT 70 88 71 85 66 / 20 20 40 40 50
SAN MARCOS MUNI AIRPORT 69 87 70 84 67 / 20 30 40 50 40
LA GRANGE - FAYETTE REGIONAL 70 87 72 85 69 / 30 30 30 50 40
SAN ANTONIO INTL AIRPORT 70 88 71 85 68 / 20 20 40 50 50
STINSON MUNI AIRPORT 71 88 71 85 69 / 20 20 40 40 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...76
SYNOPTIC/GRIDS...12
DATA COLLECTION/RADAR...26/15
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
216 AM CDT WED APR 22 2015
.AVIATION...
EARLIER TAF CONTINUED TO LEAN TOWARDS STRATUS PROSPECTS LATER
TONIGHT WITH IMPROVED MOISTURE IN SOUTHERLY FLOW AND OLD OUTFLOW
IMPACTING KCDS...WHICH STILL LOOKS LIKE MOST IMMINENT CHANCE FOR
LOW CEILING NEAR DAYBREAK. WE WILL BE WATCHING APPROACHING STRATUS
FROM THE SOUTH AS WELL WHICH COULD IMPACT KLBB AND KPVW BRIEFLY
NEAR OR JUST AFTER DAYBREAK. OTHERWISE...BEST CHANCE FOR THUNDER
LATER TODAY WILL BE ALONG AND JUST NORTH OF A STATIONARY BOUNDARY
THAT WILL BE JUST SOUTH OF KCDS LATER TODAY THUS EARNING A PROB30
FOR THUNDER. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 633 PM CDT TUE APR 21 2015/
AVIATION...
ISOLATED SHOWERS NEAR THE NM STATE LINE WEST OF LUBBOCK EXPECTED
TO DISSIPATE BEFORE REACHING KLBB AND KPVW. ATTENTION THEN SHIFTS
TO POTENTIAL FOR LOW CLOUDS WEDNESDAY MORNING. BETTER CHANCES
APPEAR TO BE AT KCDS BEHIND A WEAK COLD FRONT OR OUTFLOW BOUNDARY
THAT WILL BE PUSHED SOUTH THROUGH THE PANHANDLE LATER TONIGHT.
LOW LEVEL MOISTURE ADVECTION BEHIND THE RETREATING DRYLINE COULD
LEAD TO SOME FOG AND/OR STRATUS AT BOTH KLBB AND KPVW TOWARD 12Z
BUT SIGNAL NOT QUITE AS STRONG. WILL KEEP THOSE TAFS AS INHERITED
AND REEVALUATE WITH THE 06Z ISSUANCE.
PREV DISCUSSION... /ISSUED 344 PM CDT TUE APR 21 2015/
SHORT TERM...
SURFACE DEWPOINTS HAVE BEEN FAIRLY STAGNANT ACROSS THE FORECAST AREA
TODAY AS MODEST ADVECTION BALANCES MIXING. AT 3 PM...SATELLITE
IMAGERY SHOWED A DEVELOPING CUMULUS FIELD IN EASTERN NEW MEXICO
WHERE THE DEWPOINTS ARE MOSTLY IN THE 30S. MORE EXTENSIVE
DEVELOPMENT WAS ONGOING ACROSS THE SACRAMENTOS AND SANGRES OF NM.
THE HRRR HAS BEEN FAIRLY CONSISTENT WITH BRINGING SOME OF THIS
ACTIVITY EASTWARD ACROSS THE WESTERN AND CENTRAL SOUTH PLAINS LATE
THIS AFTERNOON AND EVENING...ALTHOUGH IT IS ABOUT THE ONLY MODEL TO
DO SO. FCST SOUNDINGS IN THESE AREAS INDICATE ANY STORMS THAT DO
DEVELOP WILL BE HIGH-BASED HAVE LITTLE CAPE TO WORK WITH...SO THEY
WILL ONLY BE CAPABLE OF SPOTTY RAIN AND STRONG WIND GUSTS. IF ANY
STORMS CAN SURVIVE FARTHER TO THE EAST THIS EVENING AND ENCOUNTER
THE DEEPER MOISTURE...IT IS NOT OUT OF THE QUESTION THAT A HAIL
THREAT COULD DEVELOP...BUT THIS APPEARS UNLIKELY AT THIS TIME.
TONIGHT...THE LOW LEVEL JET WILL BRING RICHER MOISTURE NWWD INTO
WEST TEXAS...WITH THE SURFACE DRYLINE RETREATING THROUGH MOST IF NOT
ALL OF THE CWA...PERHAPS HOLDING BACK ACROSS THE FAR SW TX
PANHANDLE. NAM FCST SNDGS SHOW FOG POTENTIAL ACROSS THE SOUTHERN AND
CENTRAL SOUTH PLAINS BY EARLY WED MORNING SO WE HAVE ADDED A PATCHY
MENTION IN THE GRIDS....SOME AREAS OF LOW STRATUS ARE POSSIBLE AS
WELL. MEANWHILE TO OUR NORTH ACROSS THE PANHANDLES...THEY WILL
LIKELY SEE SOME OVERNIGHT TSTM ACTIVITY COINCIDING WITH A SWD-MOVING
COLD FRONT. IT IS UNCERTAIN WHAT IMPACT STORM COLD POOLS MAY HAVE ON
THE PROGRESS OF THE FRONT...WHICH TENDS TO LOWER OUR CONFIDENCE ON
HOW THE FRONT/OUTFLOW BOUNDARY WILL BEHAVE ON WEDNESDAY. IN
GENERAL...WE EXPECT THE BOUNDARY TO SINK SOUTH THROUGH THE FAR SRN
PANHANDLE AND POSSIBLY INTO THE NORTHERN ROLLING PLAINS. BACK TO THE
WEST...THE DRYLINE SHOULD FORM UP AND MOVE EAST AS A SURFACE TROUGH
DEVELOPS FROM EASTERN NM INTO THE ROLLING PLAINS. ALTHOUGH WE HAVE
TO STRESS A LARGE UNCERTAINTY IN THE PARTICULARS...A TRIPLE-POINT
MAY DEVELOP SOMEWHERE FROM OUR CENTRAL TO SOUTHEAST COUNTIES. BACKED
FLOW AND HIGH SURFACE MOISTURE WILL BE POSSIBLE ACROSS AT LEAST OUR
NE ZONES. WITH A MID-LVL SHORTWAVE PASSING ACROSS THE AREA DURING
THE DAY...STRONG INSTABILITY AND DEEP SHEAR IS LIKELY TO DEVELOP
ALONG AND TO THE NORTH AND EAST OF THE TRIPLE-POINT. GUIDANCE
GENERALLY SHOWS A STRONG CONVECTIVE SIGNAL IN THIS AREA BY LATE
AFTERNOON...ALTHOUGH WITH A LOT OF SPREAD RECORDING THE AREA
POTENTIALLY IMPACTED. WHERE STORMS OCCUR...SEVERE WEATHER WILL BE A
STRONG POSSIBILITY...INCLUDING THE POSSIBILITY OF TORNADOES
DEPENDING THE ORIENTATION/EVOLUTION ON THE BOUNDARY/S/. FARTHER
WEST...WE HAVE TRIMMED POPS DOWN OUR NEAR THE STATE LINE BUT LEFT A
SLIGHT CHANCE GOING ACROSS MUCH OF THE SOUTH PLAINS IN CASE THE
DRYLINE IS FARTHER WEST THAN ANTICIPATED.
LONG TERM...
THE PATTERN THEME THROUGH EARLY NEXT WEEK REMAINS THAT OF A
PROGRESSIVE ONE AS A SERIES OF SOUTHERN STREAM TROUGHS IMPACT THE
REGION. ONLY UNTIL THEREAFTER DOES THE PATTERN SHOW SIGNS OF
TRENDING MORE STAGNANT IN THE FORM OF MID-CONUS LONGWAVE RIDGING.
ALL DAYS CONSIDERED...WEDNESDAY EVENING LOOKS TO GRAB THE LIMELIGHT
FOR SENSIBLE WEATHER AS A SEVERE CONVECTIVE EPISODE SHOULD BE WELL
UNDERWAY. LOCATION OF THIS EVENT WILL BE HIGHLY DEPENDENT ON A
STATIONARY FRONT CURRENTLY PROGGED TO BISECT OUR CWA FROM NW-SE BY
LATE EVENING...THOUGH MODELS CONTINUE TO FAVOR OUR NERN COUNTIES.
BACKGROUND FORCING APPEARS RATHER SUBDUED AND LINKED MOSTLY TO A
SHORTWAVE TROUGH CRESTING SHALLOW RIDGING ALOFT AND A NORTHWARD PUSH
OF STRONGER SUBTROPICAL WINDS. THIS ALONG WITH FAVORABLE DEEP SHEAR
MAY SERVE TO KEEP CONVECTIVE MODES RESTRICTED TO ISOLATED OR
SCATTERED SUPERCELLS. FEEL 40-50 PERCENT POPS WED EVENING ARE
REPRESENTATIVE OF THIS SCENARIO FOR NOW BEFORE PRECIP EVENTUALLY
MOVES DOWNSTREAM LATE WED NIGHT.
BEYOND WEDNESDAY NIGHT...THE WAVERING FRONTAL BOUNDARY SHOULD LIFT
NORTH AS A WARM FRONT IN ADVANCE OF A MORE ROBUST TROUGH LIFTING OUT
OF THE DESERT SOUTHWEST. THIS WAVE WILL PROJECT EVEN STRONGER WINDS
ATOP THE REGION PERHAPS ACCOMPANIED BY OCCASIONAL IMPULSES AND
SLIGHT CHANCE POPS...ESPECIALLY OFF THE CAPROCK WHERE LL MOISTURE
WILL HAVE A GREATER RESIDENCE TIME. MODEL CONSENSUS IS FOR DRY
SLOTTING TO SURGE ATOP THE CAPROCK COUNTIES BY EARLY FRIDAY AND
QUICKLY SWEEP EAST AS THE BASE OF THE TROUGH LIFTS TO OUR NORTH.
THE TIMING AND PATH OF THIS TROUGH SUGGEST A WINDY DAY IS IN STORE
YET WE REMAIN A BIT RELUCTANT TO BITE ON THE STRONG WINDS AS
PROGGED BY THE GFS AT TIMES. TIME-HEIGHT X-SECTIONS SHOW NEXT TO
NIL CIRRUS...SO WE MAY NEED TO RATCHET UP OUR 20-30 MPH WINDS
EVEN FURTHER IN LATER FORECASTS IF THIS THEME PERSISTS.
BY SATURDAY...QUIETER WEATHER UNDER TRANSIENT RIDGING WILL BE
REPLACED BY ONE FINAL TROUGH AT SOME POINT ON SUNDAY AHEAD OF
MODIFIED CANADIAN AIR WHICH LOOKS TO DIVE INTO THE GULF COME
MONDAY. PRECIP MERIT FROM SUN-SUN NIGHT DOESN/T SHOW MUCH
SUBSTANCE AMONG THE LATEST GLOBAL MODELS...SO POPS WERE SCALED
BACK IN COVERAGE TO BETTER MATCH THE DRIER SUPERBLEND AND
CONSENSUS ROUTES.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 80 48 79 50 / 20 10 0 10
TULIA 79 51 78 53 / 30 20 10 10
PLAINVIEW 81 52 78 54 / 20 20 10 10
LEVELLAND 83 51 80 55 / 10 10 0 10
LUBBOCK 83 52 80 56 / 20 10 10 10
DENVER CITY 83 53 80 54 / 10 0 0 10
BROWNFIELD 83 53 81 57 / 10 10 0 10
CHILDRESS 78 56 77 60 / 50 40 20 20
SPUR 82 59 81 61 / 20 20 20 20
ASPERMONT 84 61 82 63 / 20 20 20 30
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
216 AM EDT WED APR 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL STAY SOUTH OF US TONIGHT WHILE A FRONT MOVES IN
FROM THE NORTHWEST. THIS FRONT WILL CROSS THE REGION WEDNESDAY AND
SHIFT OFFSHORE BY THURSDAY MORNING RESULTING IN BREEZY CONDITIONS
WEDNESDAY INTO THURSDAY AHEAD AND BEHIND THE FRONT. BY
FRIDAY...HIGH PRESSURE WILL BE SITUATED FROM THE WESTERN GREAT
LAKES...SOUTH INTO THE SOUTHERN APPALACHIANS.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 200 AM EDT WEDNESDAY...
SOME TEMPERATURE ADJUSTMENTS WERE NEEDED AS INCREASING CLOUD COVER
ACROSS THE WESTERN MOUNTAINS RESULTING IN TEMPS HOLDING CLOSE TO
50...WHILE PIEDMONT AREAS WELL DOWN INTO THE 40S. CLOUDS WILL BE
INCREASING FROM THE WEST...BUT REMAIN MOSTLY CLEAR EAST OF THE
BLUE RIDGE THROUGH DAYBREAK. HAVE ADJUSTED WESTERN AREAS UP IN
TEMPERATURE...BUT KEPT EASTERN AREAS NEAR OR EVEN A DEGREE OR TWO
BELOW EARLIER ADVERTISED MIN TEMPS. MIN TEMPS COULD WELL BE
REALIZED BY 10Z IN WESTERN AREAS...THEN INCREASING WITH WEST
WINDS AND CLOUD COVER. OTHER FORECAST ELEMENTS APPEAR TO BE ON
TRACK.
AS OF 912 PM EDT TUESDAY...
EVENING SOUNDINGS AND SURFACE OBS SHOW VERY DRY AIR LINGERING OVER
THE REGION THIS EVENING AHEAD OF A WEAK TROUGH JUST WEST OF THE
MOUNTAINS AND THE NEXT COLD FRONT IN THE UPPER MIDWEST. INITIAL
BAND OF BROKEN CLOUDS NOW CROSSING THE OHIO RIVER MAY BRING A FEW
SPRINKLES TO THE WESTERN SLOPES BEFORE FADING AFTER MIDNIGHT GIVEN
DEEP WESTERLY FLOW AND A LINGERING WELL MIXED DRY LAYER JUST OFF
THE SURFACE. APPEARS NEXT ROUND OF POTENTIAL SHOWERS WONT ARRIVE
UNTIL WED MORNING AHEAD OF THE FRONT SO TRIMMING BACK WESTERN POPS
A BIT MORE OVERNIGHT SIMILAR TO THE LATEST HRRR TRENDS. OTRW
MOSTLY CLEAR TO INIT THEN BECOMING PARTLY TO MOSTLY CLOUDY AT
TIMES FAR WEST AND PC ELSW LATE. TEMPS TO ZOOM DOWN IN THE WESTERN
VALLEYS EARLY ON AS WINDS FADE WITH SOME SPOTS FALLING INTO THE
30S BEFORE BUMPING UP WITH CLOUDS LATER ON. LATEST LAV MOS SLOW TO
DROP VALUES BUT LIKELY TOO WARM EXCEPT ON THE RIDGES GIVEN SUCH
LOW DEWPOINTS THIS EVENING SO ONLY MAKING SLIGHT TWEAKS IN SPOTS.
PREVIOUS DISCUSSION AS OF 300 PM EDT TUESDAY...
VERY DRY AT THE MOMENT WITH FEW TO SCATTERED CU. UPSTREAM...SFC FRONT
WORKING INTO THE MIDWEST WILL BE OUR NEXT WEATHER MAKER...AND WIND
WILL BE THE MAIN CULPRIT.
THIS EVENING INTO THE OVERNIGHT THE SKIES WILL BE STAY CLEAR TO
PARTLY CLOUDY THEN SHOULD SEE MORE CLOUDS ARRIVE AFTER MIDNIGHT INTO
THE MTNS. SLOWED DOWN ONSET OF POPS GIVEN DRY LOW LVLS...THOUGH WILL
SEE A FEW SHOWERS MAKE IT TO GREENBRIER TO THE MTN EMPIRE AROUND
DAWN.
TEMPS WILL BE DROPPING QUICKER THIS EVENING ONCE THE WINDS SETTLE
DOWN SOME. ALOFT HOWEVER...WINDS SHOULD STAY UP KEEPING HIGHER
TERRAIN MIXED. KEEPING THE WRN SLOPES IN THE 40S FOR LOWS...WHILE
VALLEYS IN THE MTNS AND FOOTHILLS FALL INTO THE UPPER 30S. NOT
EXPECTING ANY FROST/FREEZE CONCERNS.
FOR WEDNESDAY....THE LOW LEVEL JET SETS UP FROM KENTUCKY TO MARYLAND
DURING THE MORNING/EARLY AFTERNOON. SFC FRONT WILL MAKE IT INTO THE
WV MTNS BY MIDDAY THEN SLOWLY DROP SE INTO THE PIEDMONT BY EVENING.
STABILITY SEEMS MARGINAL BUT WIND ENERGY WITH SHOWERS ARE A CONCERN
FOR GUSTY SHOWERS AND POSSIBLE THUNDERSTORMS. SPC HAS MARGINAL RISK
EAST OF ROANOKE TOWARD LYH/RIC...FOR DAMAGING WINDS. ATTM...WILL
HAVE GUSTY WIND WORDING IN THE THUNDERSTORMS FOR WED AFTERNOON.
THE WAA PATTERN AND WINDS ALOFT FAVOR SOME OF THE HIGHER RIDGES FROM
HSP TO BOONE TO GET CLOSE TO ADVISORY LEVELS OF 46 MPH FOR GUSTS.
OVERALL..THE WINDS WILL STAY BELOW THIS AS WE USUALLY NEED A 50-55
KT 8H JET AND THE MODELS KEEP THE BEST WINDS SITUATED NORTH OF US.
WEDNESDAY WILL NOT BE WASHOUT AND WSW FLOW AT TIMES SHOULD LIMIT
STORM/SHOWER DEVELOPMENT EAST OF THE MTNS...BUT ENOUGH BACKING
SHOULD ALLOW FOR OVERALL LOW LVL CONVERGENCE NOT TO KEEP IT
COMPLETELY DRY.
GOING TOWARD DUSK...THE SHOWERS WILL FADE IN COVERAGE. WEDNESDAY
WILL BE MILD/SEASONAL WITH HIGHS FROM THE UPPER 50S SE WV TO LOWER
TO MID 70 SOUTHEAST.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
AS OF 230 PM EDT TUESDAY...
A WEAK COLD FRONT WILL SLIDE EAST OF THE AREA WEDNESDAY EVENING. ANY
LINGERING SHOWERS WILL DISSIPATE BY 10P WITH LOSE OF HEATING AND
INCREASE DRIER AIR ADVECTION. THE 12Z GFS IS IN AGREEMENT WITH THIS
SCENARIO...SO THE FORECAST IS MORE HEAVILY WEIGHTED TO THAT
SOLUTION. HIGH PRESSURE CONTINUES TO BUILD EAST INTO THE AREA
THURSDAY...HOWEVER A MODEST PRESSURE GRADIENT WILL KEEP BREEZY AND
GUSTY NORTHWEST WINDS OVER THE AREA THROUGH THE DAY. THE CENTER OF
THE HIGH DRIFTS OVER THE AREA THURSDAY NIGHT WITH CALMING WINDS AND
COOLER THAN NORMAL TEMPERATURES INTO THE DAY FRIDAY. TEMPERATURES
THURSDAY AND FRIDAY WILL RANGE FROM THE UPPER 50S TO LOWER 60S
ACROSS THE MOUNTAINS TO MID TO UPPER 60S EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 240 PM EDT TUESDAY...
A WARM FRONT WILL ENTER THE REGION FROM THE SOUTHWEST FRIDAY NIGHT
BRINGING AN INCREASE IN CLOUDS AND THE CHANCE FOR RAIN SATURDAY
MORNING. RAIN CHANCES INCREASE DURING SATURDAY AFTERNOON AS
ISENTROPIC LIFT INCREASES WITH WARM MOIST AIR OVERRUNNING COOLER
SURFACE AIR. A SURFACE WAVE IS EXPECTED TO TRACK OVER THE TENNESSEE
VALLEY SATURDAY...THEN ACROSS THE CAROLINAS SUNDAY. THIS WAVE WILL
CONTINUE THE CHANCE FOR RAIN IN THE AREA THROUGH SUNDAY
MORNING...THEN A BACK DOOR COLD FRONT BRINGS COOLER DRIER AIR INTO
THE REGION FOR SUNDAY AFTERNOON INTO MONDAY. A STRONGER SURFACE WAVE
TRACKS ACROSS THE TENNESSEE VALLEY TO THE CAROLINA MONDAY NIGHT INTO
TUESDAY. THIS WAVE WILL HAVE MORE MOISTURE AND DYNAMICS TO BRING
SOME HEAVY RAIN AND STRONG STORMS TO THE REGION. TEMPERATURES
THROUGH THE PERIOD WILL REMAIN COOLER THAN NORMAL WITH UPPER 50S TO
LOWER 60S ACROSS THE MOUNTAINS TO MID TO UPPER 60S EAST.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 200 AM EDT WEDNESDAY...
BROAD UPPER TROUGH CENTERED OVER THE GREAT LAKES WILL CONTINUE TO
DOMINATE THE WEATHER ACROSS THE EASTERN U.S. THROUGH THE PERIOD.
MAIN FOCUS TODAY WILL BE ON A STRONG SHORT WAVE PROGGED TO TRACK
THROUGH THE BASE OF THE TROUGH ACROSS OUR REGION DURING THE
AFTERNOON. ALTHOUGH THE SFC AIR MASS IS VERY DRY IN THE WAKE OF
THE SUN-MON SYSTEM...STRONG DYNAMICS ASSOCIATED WITH THIS SHORT
WAVE WILL OVERCOME THE SFC DRYNESS AND RESULT IN ELEVATED
CONVECTION FROM MID-MORNING INTO THE AFTERNOON. WITH A 50-60KT
WESTERLY LLJ ASSOCIATED WITH THE SHORT WAVE...ANY CONVECTION COULD
BRING THESE STRONG WINDS DOWN TO THE SFC. WINDS WILL BE AN ISSUE
EVEN OUTSIDE CONVECTION...WITH A STRONG GRADIENT DEVELOPING
QUICKLY THIS MORNING. MANY LOCATIONS WILL SEE SW-W WINDS 15-20KTS
WITH GUSTS 25-35KTS IN THE 15Z-23Z TIME FRAME...VEERING MORE TO
THE WNW BY 00Z BEHIND THE SHORT WAVE AND DECREASING INTO THE
10-15KTS WITH GUSTS 20-25KTS. CIGS SHOULD BOTTOM OUT MOSTLY IN THE
040-050 RANGE...EXCEPT IN UPSLOPE AREAS BLF-LWB WHERE CIGS MAY
DROP INTO THE 030-035 RANGE DURING THE AFTERNOON IN ASSOCIATION
WITH SHRA ACTIVITY. VSBYS COULD BRIEFLY BECOME MVFR IN HEAVIER
SHOWERS MAINLY WESTERN MOUNTAINS. SPC HAS THE ENTIRE AREA EAST OF
THE ALLEGHANY FRONT OUTLOOKED FOR MARGINAL SEVERE TODAY...WITH THE
MAIN CONCERNS STRONG WINDS GUSTS GIVEN THE VERY STRONG WINDS ALOFT
AND PENNY TO QUARTER- SIZED HAIL GIVEN THE VERY COLD TEMPERATURES
ALOFT. FOR NOW...HAVE ONLY INTRODUCED TSRA FOR LYH...BUT
CONDITIONS MAY WARRANT ADDING THIS FOR BCB/ROA/DAN WITH LATER TAF
ISSUANCES.
MEDIUM TO HIGH CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID
PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID
PERIOD.
MEDIUM CONFIDENCE IN THUNDER POTENTIAL LATE MORNING THROUGH
AFTERNOON.
EXTENDED AVIATION DISCUSSION...
FRONT WILL EXIT BY WEDNESDAY NIGHT WITH HIGH PRESSURE BUILDING INTO
THE REGION FROM THE WEST THU-FRI. SOME GRADIENT REMAINS BETWEEN
DEPARTING FRONT AND HIGH TO THE WEST THURSDAY AND POSSIBLY
FRIDAY...SO GUSTY WINDS WILL REMAIN MAINLY DURING THE DAYTIME.
OVERRUNNING CLOUDS WORK INTO THE AREA FRIDAY AHEAD OF A WARM
FRONT. BY SATURDAY...ENOUGH MOISTURE TO ALLOW FOR SHOWERS AND MVFR
WITH BEST FORCING ACROSS THE CAROLINAS. THIS WILL BE POSSIBLE
INTO SUNDAY MORNING BEFORE THE SYSTEM EXITS AND SOME IMPROVEMENT
IN CIGS STARTS TO OCCUR LATER SUNDAY.
&&
.FIRE WEATHER...
AS OF 330 PM EDT TUESDAY...
WET FUELS WILL DRY OUT AS WE HEAD INTO WEDNESDAY. A FRONT WILL
APPROACH WEDNESDAY WITH GOOD MIXING OUT AHEAD OF IT. GUSTY WINDS
IN THE 25 TO 35 MPH RANGE WILL OCCUR AT TIMES OVER THE PIEDMONT
WHERE MIN RH SINKS TO 30 PERCENT DURING THE AFTERNOON. AT THIS
TIME A FEW SHOWERS AND STORMS COULD BE OCCURRING SO FIRE DANGER
FOR NOW IS LOW TO MODERATE AS 1 AND 10 HOUR FUELS HAVE EITHER
GREENED UP OR ARE GREENING UP. ISSUES WOULD BE WITH ANY LOOSE LEAF
LITTER THAT CAN DRY OUT ENOUGH...THOUGH SOILS THEMSELVES STAY
MOIST.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...JH/RAB/WP
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...RAB
FIRE WEATHER...WP
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion
National Weather Service Spokane WA
244 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing for warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Tonight and Tomorrow...Well the baroclinic band that brought
considerable clouds to Eastern Washington and Northern Idaho today
also had enough moisture fluxing through it to bring very light
afternoon sprinkles to some locations. Therefore have made use of
additional pops and mentions of sprinkles in a few locations to
address the showers expected tonight associated more with the
conditionally unstable air-mass coupled with a small disturbance
running through it tonight into tomorrow morning. The instability
increases as the low pressure area that contains the air mass digs
further to the southeast and closer to the forecast area. As a
result the 700-500mb lapse rates appear steep enough to include a
small mention of possible weak and shallow pulse thunderstorms for
tomorrow afternoon along the extreme northwest edge of the
forecast area (near the East Slopes North Cascades, Northern
Okanogan Valley, and Northern Okanogan Highlands. With such a cold
pool aloft in the vicinity forecast temperatures remain a bit on
the cool side of what would be considered normal for this time of
year. /Pelatti
Friday night through Sunday night...A cool and showery weather
pattern is expected through Saturday before a flat ridge brings
drier conditions (except along the Cascade crest) for Sunday.
There is general model agreement of a closed low near Vancouver
Island Friday evening dropping southeast into the North Washington
Cascades on Saturday. The position of the low and its track will
favor downslope flow off the Cascades into the Columbia Basin
which should reduce overall coverage of showers over the Columbia
Basin, and possible the Spokane area and palouse as well. Slightly
higher dew points as well as upslope flow into the northern
mountains and Idaho Panhandle will favor showers especially
Saturday afternoon as lapse rates steepen with day time heating.
The cold pool aloft at 500mb Saturday afternoon will be centered
over the Cascades with the GFS and NAM showing uncapped CAPE
values around 200-500 J/KG which could trigger a few thunderstorms
with small hail. Elsewhere the thunder chances are low and left
out of the forecast.
The low pulls east of the area on Sunday with a few lingering
showers over the Idaho Panhandle. Attention then shifts to a moist
atmospheric river that will get picked by a low pressure system in
the Gulf of Alaska. As the plume approaches the Washington
Cascades a ridge begins to build at the same time with a dieing
warm front reaching the Washington Cascades. Moist upslope flow
will likely result in light rain at the Cascade crest, while areas
away from the crest should stay dry. JW
Sunday night through Thursday...The deep trough which will deliver
cool and wet weather through the beginning of the weekend will
likely shift east of the region by Sunday. This should bring an
end to the wet weather as a ridge moves in. The exception will be
along the northern Cascades as a weakening atmospheric river
temporarily slides over NW Washington. By Monday it looks like the
river will buckle northward into BC as a much deeper trough
develops west of 150w. How long this plume of moisture remains
north of the international border is the question. Models in good
agreement that it will be at least through Tuesday. After that the
ridge axis flattens in response to the aforementioned trough. How
strong the trough and associated cold front will be is
questionable. Most of the model solutions weaken it quickly as it
passes over the Cascades Tuesday night. Locations near the
Cascades and Canadian border will see the best chances of
precipitation as the front cruises through...however amounts will
be rather light. Suspect the bigger impact will cooling
temperatures and breezy conditions. By Wednesday a shortwave ridge
temporarily builds over the Inland NW as a stronger trough moves
toward the Washington coast. By Thursday this trough will likely
move inland providing the best chance of precipitation during this
period of the forecast. The GFS is by far the deepest solution
with the next trough with deep southwest flow firmly established
over the eastern third of Washington and the Idaho Panhandle. If
this solution comes to fruition we could see a good chance of
thunderstorms, especially over SE Washington and the southern
Panhandle, however this solution is not given much support from
the EC or Canadian models.
As for temperatures, it looks like the region will return to much
warmer than normal conditions, at least for Monday and Tuesday.
Tuesday will likely be the warmest day of the week with highs in
the mid 70s to mid 80s. After that, confidence is good that we
will cool off, but to what extent is uncertain. We still expect to
see highs remaining above normal though. fx
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 38 56 36 54 36 59 / 20 10 20 40 30 10
Coeur d`Alene 36 56 34 55 34 60 / 30 20 20 50 30 10
Pullman 37 54 35 53 34 58 / 30 10 10 50 30 10
Lewiston 42 61 40 58 39 64 / 30 20 10 50 30 10
Colville 36 59 34 58 33 63 / 30 20 20 50 30 10
Sandpoint 34 55 32 55 32 60 / 40 30 20 50 30 10
Kellogg 35 52 35 52 35 57 / 40 30 10 50 40 20
Moses Lake 37 62 37 61 35 64 / 10 10 10 20 20 0
Wenatchee 42 61 40 60 40 65 / 10 30 10 20 10 10
Omak 34 61 34 60 33 64 / 30 40 20 30 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
244 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing for warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Tonight and Tomorrow...Well the baroclinic band that brought
considerable clouds to Eastern Washington and Northern Idaho today
also had enough moisture fluxing through it to bring very light
afternoon sprinkles to some locations. Therefore have made use of
additional pops and mentions of sprinkles in a few locations to
address the showers expected tonight associated more with the
conditionally unstable air-mass coupled with a small disturbance
running through it tonight into tomorrow morning. The instability
increases as the low pressure area that contains the air mass digs
further to the southeast and closer to the forecast area. As a
result the 700-500mb lapse rates appear steep enough to include a
small mention of possible weak and shallow pulse thunderstorms for
tomorrow afternoon along the extreme northwest edge of the
forecast area (near the East Slopes North Cascades, Northern
Okanogan Valley, and Northern Okanogan Highlands. With such a cold
pool aloft in the vicinity forecast temperatures remain a bit on
the cool side of what would be considered normal for this time of
year. /Pelatti
Friday night through Sunday night...A cool and showery weather
pattern is expected through Saturday before a flat ridge brings
drier conditions (except along the Cascade crest) for Sunday.
There is general model agreement of a closed low near Vancouver
Island Friday evening dropping southeast into the North Washington
Cascades on Saturday. The position of the low and its track will
favor downslope flow off the Cascades into the Columbia Basin
which should reduce overall coverage of showers over the Columbia
Basin, and possible the Spokane area and palouse as well. Slightly
higher dew points as well as upslope flow into the northern
mountains and Idaho Panhandle will favor showers especially
Saturday afternoon as lapse rates steepen with day time heating.
The cold pool aloft at 500mb Saturday afternoon will be centered
over the Cascades with the GFS and NAM showing uncapped CAPE
values around 200-500 J/KG which could trigger a few thunderstorms
with small hail. Elsewhere the thunder chances are low and left
out of the forecast.
The low pulls east of the area on Sunday with a few lingering
showers over the Idaho Panhandle. Attention then shifts to a moist
atmospheric river that will get picked by a low pressure system in
the Gulf of Alaska. As the plume approaches the Washington
Cascades a ridge begins to build at the same time with a dieing
warm front reaching the Washington Cascades. Moist upslope flow
will likely result in light rain at the Cascade crest, while areas
away from the crest should stay dry. JW
Sunday night through Thursday...The deep trough which will deliver
cool and wet weather through the beginning of the weekend will
likely shift east of the region by Sunday. This should bring an
end to the wet weather as a ridge moves in. The exception will be
along the northern Cascades as a weakening atmospheric river
temporarily slides over NW Washington. By Monday it looks like the
river will buckle northward into BC as a much deeper trough
develops west of 150w. How long this plume of moisture remains
north of the international border is the question. Models in good
agreement that it will be at least through Tuesday. After that the
ridge axis flattens in response to the aforementioned trough. How
strong the trough and associated cold front will be is
questionable. Most of the model solutions weaken it quickly as it
passes over the Cascades Tuesday night. Locations near the
Cascades and Canadian border will see the best chances of
precipitation as the front cruises through...however amounts will
be rather light. Suspect the bigger impact will cooling
temperatures and breezy conditions. By Wednesday a shortwave ridge
temporarily builds over the Inland NW as a stronger trough moves
toward the Washington coast. By Thursday this trough will likely
move inland providing the best chance of precipitation during this
period of the forecast. The GFS is by far the deepest solution
with the next trough with deep southwest flow firmly established
over the eastern third of Washington and the Idaho Panhandle. If
this solution comes to fruition we could see a good chance of
thunderstorms, especially over SE Washington and the southern
Panhandle, however this solution is not given much support from
the EC or Canadian models.
As for temperatures, it looks like the region will return to much
warmer than normal conditions, at least for Monday and Tuesday.
Tuesday will likely be the warmest day of the week with highs in
the mid 70s to mid 80s. After that, confidence is good that we
will cool off, but to what extent is uncertain. We still expect to
see highs remaining above normal though. fx
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 38 56 36 54 36 59 / 20 10 20 40 30 10
Coeur d`Alene 36 56 34 55 34 60 / 30 20 20 50 30 10
Pullman 37 54 35 53 34 58 / 30 10 10 50 30 10
Lewiston 42 61 40 58 39 64 / 30 20 10 50 30 10
Colville 36 59 34 58 33 63 / 30 20 20 50 30 10
Sandpoint 34 55 32 55 32 60 / 40 30 20 50 30 10
Kellogg 35 52 35 52 35 57 / 40 30 10 50 40 20
Moses Lake 37 62 37 61 35 64 / 10 10 10 20 20 0
Wenatchee 42 61 40 60 40 65 / 10 30 10 20 10 10
Omak 34 61 34 60 33 64 / 30 40 20 30 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1237 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing with warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Another update to add light sprinkles to the forecast for today
associated with a large area of light radar returns drifting up
in a southwest to northeast path over the area. It is very light
and only apparent from looking at pavement or a windshield so it
is not expected to measure. /Pelatti
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 38 56 37 54 38 / 10 20 10 10 50 30
Coeur d`Alene 57 36 56 34 55 36 / 10 30 20 10 50 30
Pullman 57 37 54 36 53 35 / 10 30 10 10 50 30
Lewiston 64 42 61 41 58 39 / 10 30 20 10 50 30
Colville 60 36 59 35 58 36 / 10 30 20 20 40 30
Sandpoint 57 34 55 32 55 33 / 10 40 30 20 50 30
Kellogg 56 35 52 32 52 35 / 10 40 30 10 50 40
Moses Lake 63 37 62 40 61 37 / 10 10 10 10 20 20
Wenatchee 62 42 61 42 60 40 / 10 10 30 10 20 10
Omak 62 34 61 36 60 34 / 10 30 40 20 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1237 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing with warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Another update to add light sprinkles to the forecast for today
associated with a large area of light radar returns drifting up
in a southwest to northeast path over the area. It is very light
and only apparent from looking at pavement or a windshield so it
is not expected to measure. /Pelatti
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 38 56 37 54 38 / 10 20 10 10 50 30
Coeur d`Alene 57 36 56 34 55 36 / 10 30 20 10 50 30
Pullman 57 37 54 36 53 35 / 10 30 10 10 50 30
Lewiston 64 42 61 41 58 39 / 10 30 20 10 50 30
Colville 60 36 59 35 58 36 / 10 30 20 20 40 30
Sandpoint 57 34 55 32 55 33 / 10 40 30 20 50 30
Kellogg 56 35 52 32 52 35 / 10 40 30 10 50 40
Moses Lake 63 37 62 40 61 37 / 10 10 10 10 20 20
Wenatchee 62 42 61 42 60 40 / 10 10 30 10 20 10
Omak 62 34 61 36 60 34 / 10 30 40 20 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1237 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing with warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Another update to add light sprinkles to the forecast for today
associated with a large area of light radar returns drifting up
in a southwest to northeast path over the area. It is very light
and only apparent from looking at pavement or a windshield so it
is not expected to measure. /Pelatti
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 38 56 37 54 38 / 10 20 10 10 50 30
Coeur d`Alene 57 36 56 34 55 36 / 10 30 20 10 50 30
Pullman 57 37 54 36 53 35 / 10 30 10 10 50 30
Lewiston 64 42 61 41 58 39 / 10 30 20 10 50 30
Colville 60 36 59 35 58 36 / 10 30 20 20 40 30
Sandpoint 57 34 55 32 55 33 / 10 40 30 20 50 30
Kellogg 56 35 52 32 52 35 / 10 40 30 10 50 40
Moses Lake 63 37 62 40 61 37 / 10 10 10 10 20 20
Wenatchee 62 42 61 42 60 40 / 10 10 30 10 20 10
Omak 62 34 61 36 60 34 / 10 30 40 20 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1237 PM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing with warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Another update to add light sprinkles to the forecast for today
associated with a large area of light radar returns drifting up
in a southwest to northeast path over the area. It is very light
and only apparent from looking at pavement or a windshield so it
is not expected to measure. /Pelatti
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 38 56 37 54 38 / 10 20 10 10 50 30
Coeur d`Alene 57 36 56 34 55 36 / 10 30 20 10 50 30
Pullman 57 37 54 36 53 35 / 10 30 10 10 50 30
Lewiston 64 42 61 41 58 39 / 10 30 20 10 50 30
Colville 60 36 59 35 58 36 / 10 30 20 20 40 30
Sandpoint 57 34 55 32 55 33 / 10 40 30 20 50 30
Kellogg 56 35 52 32 52 35 / 10 40 30 10 50 40
Moses Lake 63 37 62 40 61 37 / 10 10 10 10 20 20
Wenatchee 62 42 61 42 60 40 / 10 10 30 10 20 10
Omak 62 34 61 36 60 34 / 10 30 40 20 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1043 AM PDT THU APR 23 2015
.SYNOPSIS...
Near seasonal temperatures along with off and on showery
conditions will linger through the remainder of the work week. A
weather disturbance will bring a better chance of rain with higher
mountain snow showers Saturday. This is followed by high pressure
moving back into the area allowing with warm temperatures and dry
conditions to return for the beginning of next week.
&&
.DISCUSSION...
Minor updates issued earlier this morning to increase sky cover to
mostly cloudy wording for just about all locations. Radar and
observations not detecting anything in the way of precipitation
this morning which is in agreement with short term models and the
current forecast. Minor pops for orographic triggers over the
usualy favored higher mountain locations for this afternoon but
for the most part the better chance for light precipitation is
after 5 pm PDT today. Thats when the HRRR and a few other short
term models depict the next impulse of energy, rotating around
the large area of low pressure dropping down in a northwest to
southeast trajectory along the Southern British Columbia coast,
to move through Eastern Washington and Northern Idaho. It is expected
to have just enough forcing associated with its movement to allow
for a low pops and light qpf amounts for showers tonight. /Pelatti
&&
.AVIATION...
18Z TAFS: Considerable cloud cover remains at levels high enough
to allow VFR conditions to continue through the aviation interval.
A weak weather disturbance passing through Eastern Washington
after 00Z Friday will allow for spotty showers which could allow
for brief intervals of MVFR ceilings. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 38 56 37 54 38 / 10 20 10 20 50 30
Coeur d`Alene 57 36 56 34 55 36 / 10 30 10 20 50 40
Pullman 57 37 54 36 53 35 / 10 30 10 10 50 40
Lewiston 64 42 61 41 58 39 / 10 30 10 10 50 40
Colville 60 36 59 35 58 36 / 10 30 20 20 40 30
Sandpoint 57 34 55 32 55 33 / 10 40 20 30 50 30
Kellogg 56 35 52 32 52 35 / 10 40 20 20 50 50
Moses Lake 63 37 62 40 61 37 / 10 10 10 10 20 10
Wenatchee 62 42 61 42 60 40 / 10 10 30 10 20 10
Omak 62 34 61 36 60 34 / 10 30 40 30 30 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND
304 AM PDT WED APR 22 2015
.SYNOPSIS...ISOLATED POST-FRONTAL SHOWERS THIS MORNING SHOULD END
THIS AFTERNOON. A COUPLE OF WEAK FRONTS WILL BRING PERIODS OF LIGHT
RAIN THURSDAY AND FRIDAY. FEW SHOWERS WILL LINGER SATURDAY. A WARM
FRONT WILL BRUSH ACROSS THE AREA SUNDAY...BUT AN UPPER RIDGE WILL
HELP WHISK THIS SYSTEM QUICKLY NORTHWARD....AND LIMIT PRECIPITATION
FOR NORTHWEST OREGON MONDAY AND TUESDAY.
&&
.SHORT TERM...TODAY THROUGH SATURDAY...SATELLITE IMAGERY SHOWS
WIDESPREAD OPEN-CELLED CUMULUS OVER THE NE PACIFIC EARLY THIS MORNING
IN THE WAKE OF A WEAK COLD FRONT...THAT IS CURRENTLY MOVING OVER THE
CASCADES. THE FRONT IS ON THE DRY SIDE AND HAVE NOT OBSERVED MUCH IF
ANY PRECIPITATION FROM IT. ONSHORE WINDS WILL BRING THE SHOWERS FROM
THE PACIFIC TO THE NORTH COAST AND NORTH COAST RANGE THIS
MORNING...BUT THE REST OF THE AREA SHOULD REMAIN MOSTLY DRY. MID AND
HIGH CLOUDS OVER THE CASCADES AND CASCADE FOOTHILLS ASSOCIATED WITH
THE DECAYING FRONT SHOULD DEPART THE AREA THIS AFTERNOON. A COLDER
AIRMASS OVER THE REGION WILL MAINTAIN NEAR OR SLIGHTLY BELOW NORMAL
MAXIMUM TEMPERATURES TODAY...DESPITE ANY SUN BREAKS.
MODELS HAVE SLOWED THE TIMING OF THE NEXT APPROACHING FRONT...AND DO
NOT EXPECT PRECIPITATION TO RETURN TO THE COAST UNTIL EARLY THURSDAY
MORNING...AND INLAND AREAS THURSDAY AFTERNOON. SOME CLEARING TONIGHT
WILL RESULT IN COLD OVERNIGHT TEMPERATURES AND EXPECT SOME INLAND
AREAS TO DIP INTO THE 30S. THE FRONT ON THURSDAY HAS A BIT MORE
MOISTURE THAN THE CURRENT FRONT...AND MORE AREAS SHOULD SEE SOME
MEASURABLE PRECIPITATION THURSDAY AFTERNOON AND EVENING...BUT TOTALS
WILL STILL BE LIGHT...LESS THAN 0.25 INCH. THE FRONT WILL MOVE EAST
OF THE AREA LATE THURSDAY NIGHT.
AN UPPER LOW WILL MAINTAIN COOL AND SHOWERY WEATHER FRIDAY AND
SATURDAY WITH SNOW LEVELS REMAINING NEAR OR JUST BELOW THE CASCADE
PASSES. QPF WILL REMAIN LOW...AN DOD NOT EXPECT MUCH IF ANY SNOW
ACCUMULATION WITH THE SHOWERS. TJ
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS HAVE BEEN
STRUGGLING WITH THE LONG TERM FORECAST...BUT ARE BEGINNING TO SHOW
SOME AGREEMENT THAT A WARM FRONT WILL PRODUCE LIGHT RAIN ACROSS THE
REGION SUNDAY BEFORE AN UPPER RIDGE BUILDS OVER THE AREA. THE UPPER
RIDGE MAY SEND APPROACHING FRONTS NORTH OF THE PORTLAND FORECAST AREA
AND HAVE TRENDED TOWARDS A DRIER AND WARMER FORECAST FOR MUCH OF THE
LONG TERM. THE MODELS HAVE BEEN VERY INCONSISTENT RUN TO RUN...AND SO
DID NOT COMPLETELY REMOVE THE CHANCE FOR PRECIPITATION. TJ
&&
.AVIATION...CIGS ARE STARTING TO RISE AND BREAK UP BEHIND THE
FRONT THIS EVENING. MODELS HAVE BACKED OFF MVFR CIGS RETURNING
OVERNIGHT AND IN THE EARLY WEDNESDAY MORNING HOURS...EXCEPT A FEW
HOURS ALONG THE COAST WITH CIGS POSSIBLY JUST BELOW 3000 FT. WINDS
ARE ALREADY STARTING TO DECREASE AND WILL CONTINUE TO DO SO
OVERNIGHT...BUT NW WINDS MAY REMAIN GUSTY TO AROUND 20 KT ALONG
THE COAST. EXPECT VFR CONDITIONS INLAND THROUGHOUT THE DAY
WEDNESDAY AND BACK TO VFR BY LATE WED MORNING ALONG THE COAST.
KPDX AND APPROACHES...CIGS RISING THIS EVENING AND WILL BREAK UP
OVERNIGHT. COULD SEE A CIG REDEVELOP AROUND 4000 TO 5000 FT WED
MORNING BUT CONDITIONS ARE EXPECTED TO REMAIN VFR THROUGH THE
FORECAST PERIOD. WINDS WILL CONTINUE TO DECREASE THROUGH THE
OVERNIGHT HOURS.
&&
.MARINE...MINOR TWEAKING OF WINDS AND SEAS OVER NEXT 24 HOURS
WITH THE EVENING UPDATE. MODELS ARE IN AGREEMENT WITH TRENDING
WINDS DOWN MORE QUICKLY WEDNESDAY BUT WILL WAIT FOR FURTHER
CONFIRMATION BEFORE SHORTENING THE SMALL CRAFT ADVISORY. BOWEN
PREVIOUS DISCUSSION...AFTER QUITE SOME TIME...BUOY 50 APPEARS TO
HAVE RETURNED THIS AFTERNOON! NWLY SMALL CRAFT ADVISORY WINDS WITH
GUSTS 25-30 KTS WILL CONTINUE ACROSS THE COASTAL WATERS THROUGH
LATE TONIGHT/ EARLY WEDNESDAY MORNING. SEAS SLOWLY RISING THIS
AFTERNOON AS WELL...WITH A NWLY SWELL AROUND 10 FT EXPECTED TO
ARRIVE BY THIS EVENING AND PEAKING AROUND 11-12 FT TONIGHT. SEAS
GRADUALLY SUBSIDE BELOW 10 FT MIDDAY WEDNESDAY. A MUCH STRONGER
FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL
LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING
SEAS.
EXPECT ROUGH COLUMBIA RIVER BAR CONDITIONS DURING THE NEXT FEW
EBBS. WILL HAVE TO WATCH THE TONIGHT PERIOD AND IF SEAS RISE A
LITTLE HIGHER THAN ANTICIPATED ROUGH COLUMBIA RIVER BAR CONDITIONS
MAY OCCUR DURING NON EBB TIME. /27
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM PDT
WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 PM
PDT THIS EVENING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
10 AM PDT WEDNESDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
238 AM PDT WED APR 22 2015
.SYNOPSIS...
A cold front will move through the area and bring cooler weather
and breezy conditions today. More seasonal temperatures and off
and on showery conditions will linger through the remainder of the
work week. A slightly stronger weather disturbance will result in
scattered, mainly mountains rain and snow showers Thursday night
into the weekend. High pressure with warm temperatures and dry
conditions will return for the beginning of next week.
&&
.DISCUSSION...
Today through Thursday...The upper trough and associated cold
front will slide through the region today bringing a chance of
showers to the Inland Northwest. The front itself is moisture
starved but there is a band of moisture moving up from the south
ahead of the front. This may be enough to conjure up isolated to
scattered showers across the southeast zones and into the Idaho
panhandle mountains but a few hundredths of an inch of
precipitation is likely all we will see from passing showers. The
cooler more dense marine air is accelerating down the Cascade gap
valleys and into the basin and Palouse with gusts generally in the
25 to 35 mph range with some of the windier ridgetop locations
occasionally gusting to 45 mph. Expect breezy to windy conditions
to continue through late this evening then winds will start to
diminish after midnight.
The presence of the upper trough and more cloud cover will keep
daytime temperatures about 12 to 15 degrees cooler that yesterday.
Tonight a flat ridge will briefly move over the region and if we
get a decent period of clearing along with light winds, the
northern valleys could get quite chilly overnight. Some mid to
high clouds will spread across the region in advance of the next
Pacific trough and this may keep overnight temperatures from
falling too much below the freezing mark. For Thursday, expect a
mostly dry day between systems before the next chance of showers
pushes into the Cascades late in the day. Temperatures will be
close to seasonal normals. /Kelch
Thursday night through Tuesday...The models appear to be
converging on a similar solution with the upper level low
Thursday night through Saturday evening. That closed low is
expected to drop through the Gulf of Alaska then take a drunken
and wobbly course south and east through southern B.C. and
northern Washington, before opening into a wave and exiting to the
east on Sunday. This is quite a bit different then what we were
looking at 24 hours ago, and will result in a much drier forecast
for the weekend. Sunday through Tuesday guidance begins to show
some differences as high pressure builds back into the Pac NW
ahead of another incoming Pacific wave.
Thursday night through Sunday moisture and small embedded short
waves will wrap around the upper level low. There is some weak
surface based instability each afternoon. This all adds up to a
chance for showers at times through the period. While just about
anywhere could see showers, the focus, as is typical, will be for
the mountains surrounding the Basin and Palouse. Showers will be
spotty and inconsistent, but should be more prominent with
afternoon heating. Snow levels will result in some light snow
accumulations mainly above 4000 feet. Temperatures will be cool
compared to the past several days with temps in the 50s and lower
60s which is just on the cool side of normal. Expect mainly
southwest winds around 10 mph, but winds are expected to become
breezy on Sunday as the upper low moves out and high pressure
begins to build off the coast.
Sunday through Tuesday...All of the model guidance is showing the
ridge building in from the west Sunday afternoon then
strengthening Monday and Tuesday. The differences show up on just
how strong the ridge becomes and the location of the ridge axis.
Southwest flow will tap into deeper moisture, but it now looks
like the strong atmospheric river is much less potent. In addition
the ridge should push any moisture north of the Inland Northwest.
With that in mind we kept some low end pops for Sunday, but then
dried out the forecast through Tuesday. Some light rain will be
possible along the Cascade crest, but any precipitation amounts
would tend to be light. South to southwest flow will result in
warming temperatures with afternoon temperatures jumping back up
into the mid 60s to mid 70s Monday and Tuesday. Winds will be out
of the south- southwest and remain 5-15 mph. Tobin
&&
.AVIATION...
06Z TAFS: A cold front will sweep across the region tonight. Showers
are expected to develop from around the KLWS/KPUW area and extend
up toward KCOE after 12Z. There is a slight possibility for MVFR
conditions with these showers, but is not expected due to the
amount of dry air that exists at low levels. Winds will be breezy
across much of the region through Wednesday afternoon with gusts
up to between 20-30 mph possible. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 36 60 39 57 37 / 10 0 0 20 10 10
Coeur d`Alene 58 34 61 37 57 35 / 20 10 0 20 20 10
Pullman 56 33 59 38 55 35 / 30 0 10 20 10 10
Lewiston 63 37 66 43 62 40 / 30 0 0 20 20 10
Colville 62 34 63 37 60 36 / 20 10 0 30 20 20
Sandpoint 57 32 60 35 56 33 / 30 10 10 30 20 20
Kellogg 54 34 60 36 54 34 / 30 10 0 30 30 10
Moses Lake 65 37 65 39 63 38 / 0 0 0 10 10 10
Wenatchee 64 42 64 43 62 41 / 0 0 0 10 20 20
Omak 64 34 64 37 62 35 / 10 10 10 20 30 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
238 AM PDT WED APR 22 2015
.SYNOPSIS...
A cold front will move through the area and bring cooler weather
and breezy conditions today. More seasonal temperatures and off
and on showery conditions will linger through the remainder of the
work week. A slightly stronger weather disturbance will result in
scattered, mainly mountains rain and snow showers Thursday night
into the weekend. High pressure with warm temperatures and dry
conditions will return for the beginning of next week.
&&
.DISCUSSION...
Today through Thursday...The upper trough and associated cold
front will slide through the region today bringing a chance of
showers to the Inland Northwest. The front itself is moisture
starved but there is a band of moisture moving up from the south
ahead of the front. This may be enough to conjure up isolated to
scattered showers across the southeast zones and into the Idaho
panhandle mountains but a few hundredths of an inch of
precipitation is likely all we will see from passing showers. The
cooler more dense marine air is accelerating down the Cascade gap
valleys and into the basin and Palouse with gusts generally in the
25 to 35 mph range with some of the windier ridgetop locations
occasionally gusting to 45 mph. Expect breezy to windy conditions
to continue through late this evening then winds will start to
diminish after midnight.
The presence of the upper trough and more cloud cover will keep
daytime temperatures about 12 to 15 degrees cooler that yesterday.
Tonight a flat ridge will briefly move over the region and if we
get a decent period of clearing along with light winds, the
northern valleys could get quite chilly overnight. Some mid to
high clouds will spread across the region in advance of the next
Pacific trough and this may keep overnight temperatures from
falling too much below the freezing mark. For Thursday, expect a
mostly dry day between systems before the next chance of showers
pushes into the Cascades late in the day. Temperatures will be
close to seasonal normals. /Kelch
Thursday night through Tuesday...The models appear to be
converging on a similar solution with the upper level low
Thursday night through Saturday evening. That closed low is
expected to drop through the Gulf of Alaska then take a drunken
and wobbly course south and east through southern B.C. and
northern Washington, before opening into a wave and exiting to the
east on Sunday. This is quite a bit different then what we were
looking at 24 hours ago, and will result in a much drier forecast
for the weekend. Sunday through Tuesday guidance begins to show
some differences as high pressure builds back into the Pac NW
ahead of another incoming Pacific wave.
Thursday night through Sunday moisture and small embedded short
waves will wrap around the upper level low. There is some weak
surface based instability each afternoon. This all adds up to a
chance for showers at times through the period. While just about
anywhere could see showers, the focus, as is typical, will be for
the mountains surrounding the Basin and Palouse. Showers will be
spotty and inconsistent, but should be more prominent with
afternoon heating. Snow levels will result in some light snow
accumulations mainly above 4000 feet. Temperatures will be cool
compared to the past several days with temps in the 50s and lower
60s which is just on the cool side of normal. Expect mainly
southwest winds around 10 mph, but winds are expected to become
breezy on Sunday as the upper low moves out and high pressure
begins to build off the coast.
Sunday through Tuesday...All of the model guidance is showing the
ridge building in from the west Sunday afternoon then
strengthening Monday and Tuesday. The differences show up on just
how strong the ridge becomes and the location of the ridge axis.
Southwest flow will tap into deeper moisture, but it now looks
like the strong atmospheric river is much less potent. In addition
the ridge should push any moisture north of the Inland Northwest.
With that in mind we kept some low end pops for Sunday, but then
dried out the forecast through Tuesday. Some light rain will be
possible along the Cascade crest, but any precipitation amounts
would tend to be light. South to southwest flow will result in
warming temperatures with afternoon temperatures jumping back up
into the mid 60s to mid 70s Monday and Tuesday. Winds will be out
of the south- southwest and remain 5-15 mph. Tobin
&&
.AVIATION...
06Z TAFS: A cold front will sweep across the region tonight. Showers
are expected to develop from around the KLWS/KPUW area and extend
up toward KCOE after 12Z. There is a slight possibility for MVFR
conditions with these showers, but is not expected due to the
amount of dry air that exists at low levels. Winds will be breezy
across much of the region through Wednesday afternoon with gusts
up to between 20-30 mph possible. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 36 60 39 57 37 / 10 0 0 20 10 10
Coeur d`Alene 58 34 61 37 57 35 / 20 10 0 20 20 10
Pullman 56 33 59 38 55 35 / 30 0 10 20 10 10
Lewiston 63 37 66 43 62 40 / 30 0 0 20 20 10
Colville 62 34 63 37 60 36 / 20 10 0 30 20 20
Sandpoint 57 32 60 35 56 33 / 30 10 10 30 20 20
Kellogg 54 34 60 36 54 34 / 30 10 0 30 30 10
Moses Lake 65 37 65 39 63 38 / 0 0 0 10 10 10
Wenatchee 64 42 64 43 62 41 / 0 0 0 10 20 20
Omak 64 34 64 37 62 35 / 10 10 10 20 30 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
238 AM PDT WED APR 22 2015
.SYNOPSIS...
A cold front will move through the area and bring cooler weather
and breezy conditions today. More seasonal temperatures and off
and on showery conditions will linger through the remainder of the
work week. A slightly stronger weather disturbance will result in
scattered, mainly mountains rain and snow showers Thursday night
into the weekend. High pressure with warm temperatures and dry
conditions will return for the beginning of next week.
&&
.DISCUSSION...
Today through Thursday...The upper trough and associated cold
front will slide through the region today bringing a chance of
showers to the Inland Northwest. The front itself is moisture
starved but there is a band of moisture moving up from the south
ahead of the front. This may be enough to conjure up isolated to
scattered showers across the southeast zones and into the Idaho
panhandle mountains but a few hundredths of an inch of
precipitation is likely all we will see from passing showers. The
cooler more dense marine air is accelerating down the Cascade gap
valleys and into the basin and Palouse with gusts generally in the
25 to 35 mph range with some of the windier ridgetop locations
occasionally gusting to 45 mph. Expect breezy to windy conditions
to continue through late this evening then winds will start to
diminish after midnight.
The presence of the upper trough and more cloud cover will keep
daytime temperatures about 12 to 15 degrees cooler that yesterday.
Tonight a flat ridge will briefly move over the region and if we
get a decent period of clearing along with light winds, the
northern valleys could get quite chilly overnight. Some mid to
high clouds will spread across the region in advance of the next
Pacific trough and this may keep overnight temperatures from
falling too much below the freezing mark. For Thursday, expect a
mostly dry day between systems before the next chance of showers
pushes into the Cascades late in the day. Temperatures will be
close to seasonal normals. /Kelch
Thursday night through Tuesday...The models appear to be
converging on a similar solution with the upper level low
Thursday night through Saturday evening. That closed low is
expected to drop through the Gulf of Alaska then take a drunken
and wobbly course south and east through southern B.C. and
northern Washington, before opening into a wave and exiting to the
east on Sunday. This is quite a bit different then what we were
looking at 24 hours ago, and will result in a much drier forecast
for the weekend. Sunday through Tuesday guidance begins to show
some differences as high pressure builds back into the Pac NW
ahead of another incoming Pacific wave.
Thursday night through Sunday moisture and small embedded short
waves will wrap around the upper level low. There is some weak
surface based instability each afternoon. This all adds up to a
chance for showers at times through the period. While just about
anywhere could see showers, the focus, as is typical, will be for
the mountains surrounding the Basin and Palouse. Showers will be
spotty and inconsistent, but should be more prominent with
afternoon heating. Snow levels will result in some light snow
accumulations mainly above 4000 feet. Temperatures will be cool
compared to the past several days with temps in the 50s and lower
60s which is just on the cool side of normal. Expect mainly
southwest winds around 10 mph, but winds are expected to become
breezy on Sunday as the upper low moves out and high pressure
begins to build off the coast.
Sunday through Tuesday...All of the model guidance is showing the
ridge building in from the west Sunday afternoon then
strengthening Monday and Tuesday. The differences show up on just
how strong the ridge becomes and the location of the ridge axis.
Southwest flow will tap into deeper moisture, but it now looks
like the strong atmospheric river is much less potent. In addition
the ridge should push any moisture north of the Inland Northwest.
With that in mind we kept some low end pops for Sunday, but then
dried out the forecast through Tuesday. Some light rain will be
possible along the Cascade crest, but any precipitation amounts
would tend to be light. South to southwest flow will result in
warming temperatures with afternoon temperatures jumping back up
into the mid 60s to mid 70s Monday and Tuesday. Winds will be out
of the south- southwest and remain 5-15 mph. Tobin
&&
.AVIATION...
06Z TAFS: A cold front will sweep across the region tonight. Showers
are expected to develop from around the KLWS/KPUW area and extend
up toward KCOE after 12Z. There is a slight possibility for MVFR
conditions with these showers, but is not expected due to the
amount of dry air that exists at low levels. Winds will be breezy
across much of the region through Wednesday afternoon with gusts
up to between 20-30 mph possible. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 36 60 39 57 37 / 10 0 0 20 10 10
Coeur d`Alene 58 34 61 37 57 35 / 20 10 0 20 20 10
Pullman 56 33 59 38 55 35 / 30 0 10 20 10 10
Lewiston 63 37 66 43 62 40 / 30 0 0 20 20 10
Colville 62 34 63 37 60 36 / 20 10 0 30 20 20
Sandpoint 57 32 60 35 56 33 / 30 10 10 30 20 20
Kellogg 54 34 60 36 54 34 / 30 10 0 30 30 10
Moses Lake 65 37 65 39 63 38 / 0 0 0 10 10 10
Wenatchee 64 42 64 43 62 41 / 0 0 0 10 20 20
Omak 64 34 64 37 62 35 / 10 10 10 20 30 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
238 AM PDT WED APR 22 2015
.SYNOPSIS...
A cold front will move through the area and bring cooler weather
and breezy conditions today. More seasonal temperatures and off
and on showery conditions will linger through the remainder of the
work week. A slightly stronger weather disturbance will result in
scattered, mainly mountains rain and snow showers Thursday night
into the weekend. High pressure with warm temperatures and dry
conditions will return for the beginning of next week.
&&
.DISCUSSION...
Today through Thursday...The upper trough and associated cold
front will slide through the region today bringing a chance of
showers to the Inland Northwest. The front itself is moisture
starved but there is a band of moisture moving up from the south
ahead of the front. This may be enough to conjure up isolated to
scattered showers across the southeast zones and into the Idaho
panhandle mountains but a few hundredths of an inch of
precipitation is likely all we will see from passing showers. The
cooler more dense marine air is accelerating down the Cascade gap
valleys and into the basin and Palouse with gusts generally in the
25 to 35 mph range with some of the windier ridgetop locations
occasionally gusting to 45 mph. Expect breezy to windy conditions
to continue through late this evening then winds will start to
diminish after midnight.
The presence of the upper trough and more cloud cover will keep
daytime temperatures about 12 to 15 degrees cooler that yesterday.
Tonight a flat ridge will briefly move over the region and if we
get a decent period of clearing along with light winds, the
northern valleys could get quite chilly overnight. Some mid to
high clouds will spread across the region in advance of the next
Pacific trough and this may keep overnight temperatures from
falling too much below the freezing mark. For Thursday, expect a
mostly dry day between systems before the next chance of showers
pushes into the Cascades late in the day. Temperatures will be
close to seasonal normals. /Kelch
Thursday night through Tuesday...The models appear to be
converging on a similar solution with the upper level low
Thursday night through Saturday evening. That closed low is
expected to drop through the Gulf of Alaska then take a drunken
and wobbly course south and east through southern B.C. and
northern Washington, before opening into a wave and exiting to the
east on Sunday. This is quite a bit different then what we were
looking at 24 hours ago, and will result in a much drier forecast
for the weekend. Sunday through Tuesday guidance begins to show
some differences as high pressure builds back into the Pac NW
ahead of another incoming Pacific wave.
Thursday night through Sunday moisture and small embedded short
waves will wrap around the upper level low. There is some weak
surface based instability each afternoon. This all adds up to a
chance for showers at times through the period. While just about
anywhere could see showers, the focus, as is typical, will be for
the mountains surrounding the Basin and Palouse. Showers will be
spotty and inconsistent, but should be more prominent with
afternoon heating. Snow levels will result in some light snow
accumulations mainly above 4000 feet. Temperatures will be cool
compared to the past several days with temps in the 50s and lower
60s which is just on the cool side of normal. Expect mainly
southwest winds around 10 mph, but winds are expected to become
breezy on Sunday as the upper low moves out and high pressure
begins to build off the coast.
Sunday through Tuesday...All of the model guidance is showing the
ridge building in from the west Sunday afternoon then
strengthening Monday and Tuesday. The differences show up on just
how strong the ridge becomes and the location of the ridge axis.
Southwest flow will tap into deeper moisture, but it now looks
like the strong atmospheric river is much less potent. In addition
the ridge should push any moisture north of the Inland Northwest.
With that in mind we kept some low end pops for Sunday, but then
dried out the forecast through Tuesday. Some light rain will be
possible along the Cascade crest, but any precipitation amounts
would tend to be light. South to southwest flow will result in
warming temperatures with afternoon temperatures jumping back up
into the mid 60s to mid 70s Monday and Tuesday. Winds will be out
of the south- southwest and remain 5-15 mph. Tobin
&&
.AVIATION...
06Z TAFS: A cold front will sweep across the region tonight. Showers
are expected to develop from around the KLWS/KPUW area and extend
up toward KCOE after 12Z. There is a slight possibility for MVFR
conditions with these showers, but is not expected due to the
amount of dry air that exists at low levels. Winds will be breezy
across much of the region through Wednesday afternoon with gusts
up to between 20-30 mph possible. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 36 60 39 57 37 / 10 0 0 20 10 10
Coeur d`Alene 58 34 61 37 57 35 / 20 10 0 20 20 10
Pullman 56 33 59 38 55 35 / 30 0 10 20 10 10
Lewiston 63 37 66 43 62 40 / 30 0 0 20 20 10
Colville 62 34 63 37 60 36 / 20 10 0 30 20 20
Sandpoint 57 32 60 35 56 33 / 30 10 10 30 20 20
Kellogg 54 34 60 36 54 34 / 30 10 0 30 30 10
Moses Lake 65 37 65 39 63 38 / 0 0 0 10 10 10
Wenatchee 64 42 64 43 62 41 / 0 0 0 10 20 20
Omak 64 34 64 37 62 35 / 10 10 10 20 30 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1058 PM PDT TUE APR 21 2015
.SYNOPSIS...
A cold front will move through the area and bring cooler weather
and breezy conditions late tonight and on into Wednesday. Cooler
temperatures and off and on showery conditions will linger on
through the remainder of the work week. A stronger weather
disturbance will result in widespread and possibly moderate
precipitation Sunday into Monday.
&&
.DISCUSSION...
Satellite imagery shows the mid level cold front beginning to push
into the Cascade Mtns late this evening. Water vapor imagery also
shows some enhancement ahead of this front across central OR and
moving up into central WA. The atmosphere is so dry across the
region that it is going to take another 6 hours or so before the
atmosphere moistens up enough that showers begin to pop up over
the area. The best mid level instability will be across the ID
Panhandle into extreme eastern portions of WA. This is where
models are showing the best chances for precip as that mid level
front cross east of the Cascades through the morning on Wednesday.
The NAM continues to be the most aggresive with a precip as it
shows a convective bullseye over the Northeast Blue Mtns and
extending into the Central Panhandle Mtns. The GFS, ECMWF and
even the HRRR show much less potential for precip with the
showers. This makes more sense as not much precip has fallen west
of the Cascades with the front, which is sign that there just
isn`t much moisture to work with. Shower coverage is expected to
be isolated to scattered.
There will also be a pronounced dry slot that moves in with the
front. This dry air will wrap into the region as the upper level
low pressure system tracks across the southern BC border. The cold
pool aloft is not that deep as well, so not expecting much in the
way of afternoon convection on Wednesday behind the front. The
main changes that were made to the forecast were to lower precip
chances a bit and mainly for Wednesday afternoon. I also lowered
temperatures some for tonight as well. The cold front will advect
in a considerable amount of cold air. Good cold air advection will
also result in breezy winds through tonight. Winds are already
getting fairly gusty in the lee of the Cascades. Expect these
winds to spread eastward into the basin and remain breezy through
Wednesday afternoon. /SVH
&&
.AVIATION...
06Z TAFS: A cold front will sweep across the region tonight. Showers
are expected to develop from around the KLWS/KPUW area and extend
up toward KCOE after 12Z. There is a slight possibility for MVFR
conditions with these showers, but is not expected due to the
amount of dry air that exists at low levels. Winds will be breezy
across much of the region through Wednesday afternoon with gusts
up to between 20-30 mph possible. /SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 45 59 36 60 38 58 / 10 20 10 10 20 10
Coeur d`Alene 42 59 34 61 37 58 / 10 30 10 0 20 20
Pullman 43 57 32 59 37 56 / 20 30 0 0 20 10
Lewiston 47 64 37 66 43 63 / 20 40 0 0 20 20
Colville 46 63 34 63 35 61 / 10 20 20 10 30 20
Sandpoint 42 57 32 60 35 56 / 10 30 20 10 30 20
Kellogg 41 55 34 60 34 55 / 0 40 10 10 30 30
Moses Lake 45 66 36 63 38 64 / 10 0 0 10 10 10
Wenatchee 45 65 41 63 42 63 / 10 0 0 10 10 20
Omak 43 64 33 63 36 62 / 10 10 10 10 20 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
248 PM CDT WED APR 22 2015
.SHORT TERM...TONIGHT THROUGH SATURDAY
.TONIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH.
LOOK FOR VERY ISOLATED CHANCES OF RAIN AND SNOW SHOWERS TO CONTINUE
THIS AFTERNOON INTO THE EARLY EVENING BUT WILL FINALLY BEGIN TO
BREAK TONIGHT AS AN EXTENSIVE SFC LOW PRESSURE SYSTEM WILL MOVE OFF
TO THE EAST. A 500 MB SHORTWAVE TROUGH WITH ASSOCIATED SHEARED
POSITIVE VORTICITY ADVECTION WILL PERSIST OVER THE REGION THROUGH
THURSDAY AFTERNOON...BUT CONDITIONS LOOK TO BE CLEAR AS THE
ENVIRONMENTAL PROFILES FROM NAM AND RAP BUFKIT SOUNDINGS LOOK TO DRY
OUT OVERNIGHT. GUSTY NORTHWEST WINDS WILL CONTINUE TONIGHT...BUT
WILL WEAKEN AS SFC PRESSURE GRADIENT WEAKENS.
THURSDAY LOOKS LIKE A QUIETER DAY AS SFC HIGH PRESSURE MOVES INTO
THE REGION FROM THE NORTHWEST. MID-LEVEL HEIGHTS WILL RISE AS THE
HIGH PRESSURE APPROACHES. THE CAVEAT THURSDAY WILL BE CONTINUED COLD
TEMPERATURES AS WE REMAIN IN A NORTHWEST FLOW REGIME. 925 MB
TEMPERATURES WILL ONCE AGAIN BE IN THE SINGLE NEGATIVE DIGITS...WITH
LOWS DROPPING INTO THE UPPER 20S ACROSS SOUTHERN WISCONSIN. THE GOOD
NEWS IS SKIES WILL CLEAR THURSDAY AS A DRIER AIRMASS MOVES IN.
ABUNDANT SUNSHINE WILL HELP INCREASE OUR TEMPERATURES BACK INTO THE
LOWER 50S.
.THURSDAY NIGHT THROUGH SATURDAY...FORECAST CONFIDENCE MEDIUM.
QUIET CONDITIONS CONTINUE FOR THURSDAY NIGHT AND FRIDAY AS SFC
RIDGING TAKES HOLD. GOOD RADIATIONAL COOLING THURSDAY NIGHT WILL
ALLOW NEAR TO BELOW FREEZING LOW TEMPERATURES AWAY FROM THE
LAKESHORE. RIDGE SHIFTS EAST OF THE REGION FRIDAY NIGHT AS A
SHORTWAVE IMPULSE EJECTS FROM THE CENTRAL PLAINS INTO IOWA AND
MISSOURI. ASSOCIATED SFC LOW TRACKS FROM NEBRASKA INTO MISSOURI
SATURDAY MORNING...WITH PCPN SHIELD BRUSHING SOUTHERN WISCONSIN
FRIDAY EVENING. BEST OMEGA AND LAYER Q-VECTOR CONVERGENCE ARRIVES
FRIDAY NIGHT AND LASTS THROUGH EARLY SATURDAY. KEPT CHANCE POPS IN
PLACE DURING THIS TIME. TEMPS IN THE NORTHERN CWA WILL BE NEAR
FREEZING FRIDAY NIGHT...WITH A RAIN-SNOW MIX POSSIBLE. WARM
ADVECTION SHOULD KICK IN SATURDAY MORNING...WITH PCPN
TRANSITIONING TO ALL RAIN. ANY LINGERING SHOWERS SHOULD COME TO AN
END SATURDAY NIGHT. HIGHS WARM INTO THE 50S AWAY FROM THE LAKE ON
FRIDAY...BEFORE TURNING COOLER ON SATURDAY.
.LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE
MEDIUM.
DECENT MODEL AGREEMENT ON SFC RIDGING TAKING HOLD ACROSS THE
EASTERN GREAT LAKES REGION ON SUNDAY AND MONDAY. TEMPERATURES
MODERATE A BIT FROM SATURDAY...WITH HIGHS IN THE 50S LOWER 60S.
THEREAFTER...12Z GFS/00Z ECMWF RUNS ARE TAKING A MORE SOUTHERLY
TRACK WITH A LOW PRESSURE SYSTEM INITIALLY OVER THE TX PANHANDLE
ON MONDAY. WHILE PREVIOUS GFS RUN LIFTED IT WELL INTO
MISSOURI...CONSENSUS TRACK IS NOW INTO THE LOWER MISSISSIPPI
VALLEY. IN LIGHT OF THIS...AND PER COORDINATION WITH SURROUNDING
WFOS...REMOVED POPS FOR MONDAY AND EARLY TUESDAY. KEPT CHANCE
POPS FOR TUESDAY AFTERNOON INTO WEDNESDAY WITH ECMWF SHOWING
BETTER SHORTWAVE ENERGY AND GENERATING SOME LIGHT PCPN.
&&
.AVIATION/00Z TAFS/...LOW END VFR CIGS WILL CONTINUE INTO THE EARLY
EVENING AS A PERSISTENT STRATOCUMULUS DECK WILL STICK AROUND THE
AREA. THE RAP AND NAM BUFKIT SOUNDINGS SHOW THE ATMOSPHERIC PROFILE
DRYING OUT LATER THIS EVENING...IMPROVING CIG HEIGHTS. VERY ISOLATED
RAIN AND SNOW SHOWERS ARE POSSIBLE THIS AFTERNOON AND EARLY EVENING
UNTIL A DRIER AIRMASS MOVES IN DURING THE OVERNIGHT HOURS. NORTHWEST
WINDS WILL REMAIN GUSTY INTO THE EARLY EVENING HOURS...WITH GUSTS
NEAR 25 KTS POSSIBLE. WINDS WILL WEAKEN AFTER 00Z THURSDAY.
&&
.MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT UNTIL 00Z THURSDAY.
NORTHWEST WINDS WILL REMAIN GUSTY INTO THE EARLY EVENING
HOURS...WITH GUSTS NEAR 25 KTS POSSIBLE. WINDS SHOULD WEAKEN AFTER
00Z AS SFC PRESSURE GRADIENT WEAKENS. WAVES WILL BE 1-2 FT UNTIL
THE WINDS WEAKEN.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TONIGHT/THURSDAY AND AVIATION/MARINE...JTS
THURSDAY NIGHT THROUGH WEDNESDAY...SPM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
243 PM CDT WED APR 22 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 243 PM CDT WED APR 22 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED UPPER TROUGHS OVER BRITISH COLUMBIA...ALONG THE SOUTHERN
CALIFORNIA COAST...AND OVER THE FORECAST AREA INTO THE GREAT
LAKES...WHILE RIDGING EXTENDED FROM THE FOUR CORNERS OF THE U.S.
INTO ALBERTA. CYCLONIC FLOW OF MOISTURE AROUND THE GREAT LAKES UPPER
TROUGH...NICELY SEEN ON THE 12Z GRB SOUNDING...HELPING TO HOLD
STRATOCUMULUS ACROSS WI. GO A LITTLE MORE TO THE WEST OVER MN AND
IA...MUCH DRIER AIR WAS PRESENT ON THE 12Z MPX SOUNDING WITH A
PRECIPITABLE WATER OF 0.16 INCHES OR 36 PERCENT OF NORMAL. THIS
DRIER AIR HAS RESULTED IN CLEARER SKIES. A RIDGE OF HIGH PRESSURE
ACCOMPANYING THE CLEAR SKIES WAS LOCATED OVER THE EASTERN DAKOTAS. A
TIGHT PRESSURE GRADIENT EAST OF THIS RIDGE MAINTAINING A BRISK
NORTHWEST BREEZE OVER THE FORECAST AREA WITH SPEEDS/GUSTS A LITTLE
LOWER THAN 24 HRS AGO. STILL...THE SPEEDS HAVE BEEN STRONG ENOUGH TO
WARRANT THE EARLIER ISSUED WIND ADVISORY FOR A SMALL PORTION OF
NORTHEAST IOWA. AIRMASS REMAINS UNSEASONABLY COOL WITH 850MB TEMPS
IN THE -5 TO -8C RANGE...RESULTING IN THE PRESENT 40S
TEMPERATURES...AND EVEN 30S AT MEDFORD WI.
THE UPPER TROUGH AFFECTING THE FORECAST AREA INTO THE GREAT LAKES IS
PROGGED TO MAKE MUCH MORE EASTWARD PROGRESS OVER THE NEXT 24
HOURS...REACHING NEW ENGLAND BY 00Z FRI. THIS WILL ALLOW THE RIDGING
AND WARMER/DRIER AIR OVER THE NORTHERN ROCKIES AND PLAINS TO MARCH
TOWARDS THE FORECAST AREA. WE DO HAVE ONE SHORTWAVE TO CONTEND WITH
COMING DOWN THE BACK SIDE OF THE UPPER TROUGH TONIGHT...WHICH ITS
MAIN IMPACT IS TO BRING IN SLIGHTLY COOLER AIR FOR 12Z THU BEFORE
THE WARMING COMMENCES.
CLOUDS MAY BE A BIT PERSISTENT NORTHEAST OF I-94 TONIGHT...THANKS TO
THAT SHORTWAVE COMING THROUGH...BUT ELSEWHERE ANY STRATOCUMULUS WILL
DISSIPATE WITH LOSS OF DAYTIME HEATING. THIS CLEARING COMBINED WITH
WINDS DIMINISHING SOME AS THE RIDGE APPROACHES I-35 BY 12Z THU IS
EXPECTED TO RESULT IN A CHILLY NIGHT. 20S SHOULD BE COMMON ACROSS
MUCH OF THE REGION BY SUNRISE WITH PERHAPS NEAR 30 READINGS IN THE
MS RIVER VALLEY. NO FROST/FREEZE HEADLINES WILL BE POSTED YET AS
VEGETATION GROWTH IS NOT QUITE THERE. 850MB TEMPS ON THU CLIMB TO 0
TO -2C BY 00Z FRI WHICH WITH PLENTY OF SUN SHOULD BE ABLE TO BOOST
TEMPERATURES INTO THE LOW TO MID 50S FOR MOST LOCATIONS. MEDFORD
AGAIN MIGHT BE THE LONE COOLER EXCEPTION BEING CLOSER TO THE
DEPARTING COLD AIR. DEEP MIXING IS LIKELY AS WELL IN THE DRY AIRMASS
FEATURING PRECIPITABLE WATER NEAR 0.10 INCHES...CAUSING LOW RELATIVE
HUMIDITY VALUES. THE COMBINATION OF THESE LOW VALUES AND A 10 TO 15
MPH NORTHWEST BREEZE COULD RESULT IN SOME FIRE WEATHER CONCERN. SEE
FIRE WEATHER SECTION BELOW FOR MORE DETAILS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 243 PM CDT WED APR 22 2015
FIRST FOCUS OF THE LONG TERM PERIOD IS ON THE UPPER TROUGH NEAR THE
SOUTHERN CALIFORNIA COAST. MODELS ARE IN GOOD AGREEMENT LIFTING THIS
TROUGH INTO THE CENTRAL PLAINS ON FRIDAY AND INTO CENTRAL ILLINOIS
ON SATURDAY. ALTHOUGH THIS TRACK IS SOUTH OF THE FORECAST AREA...WE
STILL HAVE SOME SHOT AT PRECIPITATION DURING THE FRIDAY-SATURDAY
TIME FRAME. PART OF THIS IS DUE TO A SOMEWHAT DECENT MOISTURE SURGE
AHEAD OF THE TROUGH UP INTO THE FORECAST AREA ON FRIDAY...REFLECTED
BY PRECIPITABLE WATER CLIMBING TO AROUND 0.75 INCHES BY 00Z SAT.
ADDITIONALLY...A SHORTWAVE IS PROGGED TO EJECT OUT OF THE TROUGH AND
MOVE THROUGH THE AREA ON FRIDAY...INTERACTING WITH THE MOISTURE.
THEREFORE...CHANCES OF PRECIPITATION PERSIST FOR FRIDAY...ESPECIALLY
IN THE AFTERNOON AND INTO THE NIGHT WEST OF THE MS RIVER WHERE MORE
MOISTURE EXISTS. PRECIPITATION SHOULD BEGIN TO WANE NORTH TO SOUTH
ON SATURDAY AS THE UPPER TROUGH MOVES EAST OF OUR LONGITUDE...
CUTTING OFF THE MOISTURE TRANSPORT AND ALLOWING DRIER AIR TO GET
DRAWN IN FROM THE NORTH AND EAST. SOME MODEL DIFFERENCES EXIST ON
HOW MUCH PRECIPITATION EXISTS ON SATURDAY DUE TO SLIGHT NORTH/SOUTH
DIFFERENCES OF THE UPPER TROUGH TRACK...WITH THE 22.12Z GFS/CANADIAN
FARTHEST NORTH UP TO US-10 AND 22.12Z NAM/ECMWF FARTHEST SOUTH TO
AROUND US-20. THEREFORE...PRECIPITATION CHANCES ON SATURDAY REMAIN
AT OR BELOW 50 PERCENT. BETWEEN THE CLOUDS AND PRECIPITATION...HIGH
TEMPERATURES LOOK TO BE A LITTLE COOLER THAN ON THU.
A DRIER AND WARMER PERIOD IS ON TAP FOR SUNDAY AS AN UPPER RIDGE
AXIS APPROACHES THE FORECAST AREA FROM THE WEST. WITH 850MB TEMPS OF
0-2C...SHOULD SEE HIGHS CLIMB WELL UP INTO THE 50S AND POSSIBLY 60S
IN RIVER VALLEYS. EASTERLY FLOW FROM HIGH PRESSURE OVER ONTARIO
LIKELY TO CAUSE RELATIVE HUMIDITIES TO TANK.
MODELS HAVE CHANGED THEIR TUNE A BIT FOR SUNDAY NIGHT THROUGH MONDAY
NIGHT...LEANING TOWARDS DRIER AND WARMER. THIS IS A RESULT OF A
SHORTWAVE TROUGH COMING INTO THE PACIFIC NORTHWEST ON SATURDAY
THAT...INSTEAD OF HEADING TOWARDS THE FORECAST AREA...NOW DIGS DOWN
INTO THE SOUTHERN PLAINS. THEREFORE HAVE FOLLOWED SUIT...DRYING OUT
THE FORECAST AND RAISING TEMPERATURES.
AS WE HEAD INTO TUESDAY AND WEDNESDAY...UPPER RIDGING IS PROGGED TO
DEVELOP OVER THE WESTERN U.S. INTO WESTERN CANADA...CAUSING
SHORTWAVES TO DROP INTO THE REGION ON NORTHERLY FLOW. AS A
RESULT...SOME LOW PRECIPITATION CHANCES ARE IN THE FORECAST. HARD TO
SAY HOW MUCH PRECIPITATION WILL FALL GIVEN LACK OF MOISTURE
AVAILABILITY. DESPITE THE NORTHERLY FLOW...850MB TEMPS ARE STILL
PROGGED IN THE 2-4C RANGE SO TEMPERATURES DO NOT LOOKS TO CHANGE
MUCH FROM MONDAY AND STAY JUST BELOW SEASONABLE NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1227 PM CDT WED APR 22 2015
ANOTHER DAY OF COLDER CYCLONIC FLOW WITH ENOUGH PRESSURE GRADIENT
AND MIXING TO PRODUCE STRONG NORTHWEST WINDS. WIND GUSTS IN PARTS OF
NORTHEAST IOWA HAVE HIT 30 TO 35 KTS. MEANWHILE VFR CEILINGS STILL
HOLDING TOUGH NEAR AND EAST OF MISSISSIPPI RIVER. CUMULUS FIELD IS
FILLING IN ON WESTERN EDGE BUT DRIER AIR ALOFT IS BATTLING THAT SO
EXPECT CLEARING TO PUSH EAST WITH LOSS OF HEATING GOING INTO THIS
EVENING. THE FURTHER EAST AND NORTHEAST YOU GO...HIGH RISK OF
CEILINGS STICKING AROUND BUT GENERALLY SHOULD REMAIN VFR.
SLOW PROGRESS OF UPPER LOW COULD RESULT IN MORE PREVAILING SUNSHINE
INTO THURSDAY...AND AS COLD POOL ALOFT ALSO SHIFTS...LESS RISK OF
CUMULUS FORMING.
&&
.FIRE WEATHER...
ISSUED AT 243 PM CDT WED APR 22 2015
TODAY HAS BEEN MOSTLY A DRYING DAY WEST OF THE MISSISSIPPI RIVER
WHERE MORE SUN HAS OCCURRED...CLOSER TO THE DRIER AIR OVER WESTERN
MN AND WINDS HAVE BEEN GUSTING 30-40 MPH. A WARMER DAY IS EXPECTED
ACROSS THE REGION ON THURSDAY WITH SUNNY SKIES. ADDITIONALLY...THE
DRY AIR OVER WESTERN MN MOVES IN...PLUMMETING RH VALUES TO 20-30
PERCENT. HOWEVER...WINDS DO NOT LOOK NEARLY AS STRONG WITH HIGH
PRESSURE MOVING IN...ONLY IN THE 10 TO 15 MPH RANGE. WITH SOME
GREEN-UP ALREADY OCCURRING AND THE LIGHTER WINDS...HAVE DECLINED
TO CONSIDER ANY FIRE WEATHER HAZARDS AT THIS TIME. SOME RAIN
REMAINS ON TAP TO MOVE INTO THE REGION FOR FRIDAY...ALONG WITH
CLOUDS...WHICH BOTH SHOULD HELP MITIGATE FIRE WEATHER CONCERNS.
LOOKING AHEAD...SUNDAY COULD BE ANOTHER DAY WORTH WATCH FOR FIRE
WEATHER CONCERNS...BUT SIMILAR TO THURSDAY WINDS ARE EXPECTED ON
THE LIGHTER SIDE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ008-018-019-029.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...SHEA
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1120 AM CDT WED APR 22 2015
.UPDATE...
ISOLATED RAIN SHOWERS AND LIGHT SNOW WILL CONTINUE ACROSS OUR
FORECAST AREA THIS MORNING AND AFTERNOON AS A SFC LOW PRESSURE
SYSTEM SLOWLY MOVES OFF TO THE EAST. STEEP LOW LEVEL LAPSE RATES
ALONG WITH WEAK 850-700 MB FRONTOGENETICAL FORCING WILL HELP
SUPPORT THIS PRECIPITATION. THE 22.14Z HRRR MODEL IS SHOWING
PRECIPITATION TAPERING OFF BY THE EVENING.
NORTHWEST WINDS WILL ALSO BE STRONG THANKS TO A TIGHT SFC PRESSURE
GRADIENT BEHIND THIS LOW...WITH GUSTS NEAR 25 KTS. BOUNDARY LAYER
LOOKS TO MIX DOWN STRONGER WINDS AS RAP BUFKIT SOUNDINGS ARE
SHOWING MIXING UP TO NEAR THE 800 MB LEVEL. WINDS SHOULD WEAKEN BY
THIS EVENING.
&&
.AVIATION/18Z TAFS/...
MAINLY LOW-END VFR CIGS WILL PERSIST INTO THE AFTERNOON AS A
MOSTLY OVERCAST STRATUS DECK WILL STICK AROUND THE AREA. CIGS
WILL MAINLY BE BETWEEN 3.0-5.0 KFT THIS MORNING AND AFTERNOON.
ISOLATED RAIN SHOWERS AND LIGHT SNOW ARE POSSIBLE THROUGH THE
AFTERNOON AS A LOW PRESSURE SYSTEM OVER ONTARIO CANADA WILL SLOWLY
MOVE OUT THIS EVENING. BRIEF MVFR CONDITIONS ARE POSSIBLE IF
PRECIPITATION MOVES OVER THE TAF SITES. CIG HEIGHTS SHOULD IMPROVE
AS SKIES CLEAR TONIGHT. NORTHWEST WINDS WILL BE GUSTY DURING THE
AFTERNOON WITH DECENT BOUNDARY LAYER MIXING UP TO THE 800 MB
LEVEL. GUSTS NEAR 25 KTS POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT WED APR 22 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
THE LARGE OCCLUDED LOW PRESSURE AREA OVER THE GREAT LAKES AND
ONTARIO CANADA WILL MOVE LITTLE TODAY. THUS COOL TEMPS AND ISOLD
INSTABILITY RAIN AND SNOW SHOWERS OR FLURRIES WILL CONTINUE. THERE
COULD BE A SLIGHT ENHANCEMENT IN THE PCPN COVERAGE AND INTENSITY
OVER EAST CENTRAL WI THIS AFTERNOON INTO THE EVENING...WHERE A
SFC TROUGH AND SFC-850 MB FRONTOGENESIS WILL BE FOCUSED. OTHERWISE
FCST SOUNDINGS DO SHOW MORE CLEARING TNT WITH LOWS TEMPS IN THE
UPPER 20S TO LOWER 30S.
SHORT TERM...THURSDAY THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
MODELS ARE IN GOOD AGREEMENT WITH WEAK HIGH PRESSURE SHIFTING
EASTWARD ACROSS THE REGION THURSDAY AND THURSDAY NIGHT...SLIDING
TO THE EAST FRIDAY MORNING. AREA FORECAST SOUNDINGS SHOW A FAIRLY
DRY AIRMASS IN PLACE OVER THE REGION DURING THIS TIME.
THUS...CONTINUED THE DRY FORECAST FOR THIS PERIOD. COOL
TEMPERATURES WILL CONTINUE DURING THIS PERIOD.
MODELS SEEM TO BE IN BETTER AGREEMENT WITH THE TRACK OF THE LOW
PRESSURE SYSTEM...SHIFTING EASTWARD FROM KANSAS INTO FAR WESTERN
MISSOURI FRIDAY AND FRIDAY NIGHT. 500 MB SHORTWAVE TROUGH SLIDES
EAST SOUTHEAST FROM NEBRASKA INTO SOUTH CENTRAL IOWA FRIDAY INTO
FRIDAY NIGHT...A CONSENSUS TRACK FROM THE MODELS. THIS FEATURE
GETS CLOSE ENOUGH TO THE AREA TO BRING IN THE NORTHERN PORTIONS OF
THE QPF SHIELD FRIDAY NIGHT. THERE IS ALSO SOME LOW TO MID LEVEL Q
VECTOR CONVERGENCE THAT SHIFTS THROUGH THE REGION FRIDAY NIGHT.
AREA FORECAST SOUNDINGS BRING IN DECENT MOISTURE IN THE 650 MB TO
800 MB LAYER FRIDAY NIGHT PER GFS...WITH THE NAM MORE AGGRESSIVE
WITH DEEPER COLUMN MOISTURE. USED CONSENSUS POPS WITH SOME
UNCERTAINTY WITH THE MOISTURE...WITH HIGHEST IN THE SOUTHWEST
PORTIONS OF THE AREA FRIDAY NIGHT. TEMPERATURE PROFILES MAY GET
COLD ENOUGH LATER FRIDAY NIGHT FOR A MIX OF LIGHT RAIN AND LIGHT
SNOW IN NORTHERN AND EASTERN PORTIONS OF THE AREA. COOL
TEMPERATURES WILL CONTINUE FRIDAY INTO FRIDAY NIGHT.
LONG TERM...SATURDAY THROUGH TUESDAY...FORECAST CONFIDENCE IS
MEDIUM.
CONTINUED POPS INTO SATURDAY...AS 500 MB SHORTWAVE TROUGH SLIDES
EAST ACROSS NORTHERN ILLINOIS AND BRINGS LIGHT QPF TO PORTIONS OF
THE AREA. GFS/ECMWF ARE IN DECENT AGREEMENT WITH THIS.
GFS/ECMWF THEN SHOW SOME DIFFERENCES WITH FEATURES SATURDAY NIGHT
INTO SUNDAY NIGHT. THE GFS IS QUICKER WITH BRINGING 500 MB RIDGE
AXIS EAST ACROSS THE REGION THAN THE ECMWF. STILL...BOTH MODELS
SHOW HIGH PRESSURE TO THE NORTH OF THE REGION...KEEPING THE REGION
DRY. THUS...KEPT THE DRY FORECAST GOING FOR THIS PERIOD.
TEMPERATURES SHOULD SLOWLY MODERATE DURING THIS TIME.
GFS THEN BRINGS A STRONG LOW PRESSURE SYSTEM NORTHEAST FROM THE
SOUTHERN PLAINS INTO EAST CENTRAL MISSOURI MONDAY INTO MONDAY
NIGHT...THEN INTO NORTH CENTRAL ILLINOIS TUESDAY. A POTENT 500 MB
SHORTWAVE TROUGH ACCOMPANIES IT...BRINGING QPF TO THE REGION. THE
ECMWF SHOWS NO SUCH FEATURE. FOR NOW...USED CONSENSUS POPS AND
HAVE LOWER END POPS.
AVIATION/12Z TAFS/...
MOSTLY BROKEN STRATOCUMULUS FROM 3.5-5.0 KFT IS EXPECTED TODAY
WITH ISOLD SNOW OR RAIN SHOWERS DUE TO A LARGE AND SLOW MOVING LOW
PRESSURE AREA OVER THE GREAT LAKES AND SRN CANADA. BRIEF PERIODS
OF MVFR CIGS ARE POSSIBLE. ANY SHOWERS MAY BE ASSOCIATED WITH
MVFR CIGS AND VSBYS AS WELL. BRISK AND GUSTY WNWLY WINDS WILL
CONTINUE. FOR TNT...SKIES WILL BECOME MO CLEAR TO PTLY CLOUDY
WITH LESSENING WINDS.
MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT UNTIL 00Z THU AS BRISK AND
GUSTY WNWLY WINDS CONTINUE AROUND A LARGE AND STRONG LOW PRESSURE
AREA THAT IS OVER THE GREAT LAKES AND SRN CANADA. BY SUNSET...THE
PRESSURE GRADIENT AND MIXING WILL SUBSIDE ENOUGH TO DROP THE WINDS
BELOW SMALL CRAFT ADVISORY CRITERIA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
UPDATE...JTS
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
THURSDAY THROUGH TUESDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1201 AM CDT WED APR 22 2015
.UPDATE...
ISSUED AT 624 PM CDT TUE APR 21 2015
EVEN THOUGH WE ARE GETTING SOME OUR STRONGEST WIND GUSTS RIGHT
NOW...SOUNDINGS SHOW THAT WE WILL BE NOT MIXING AS DEEP DURING THE
NEXT HOUR. THIS MEANS THAT THESE STRONG WINDS WILL NOT LAST MUCH
LONGER. SINCE IT WOULD ONLY MEAN EXTENDING THE WIND ADVISORY BY 1
HOUR...DECIDED TO JUST LET IT EXPIRE AND REPLACE IT WITH A SPECIAL
WEATHER STATEMENT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 326 PM CDT TUE APR 21 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S. INTO ALBERTA AND VERY DEEP
TROUGHING OVER THE FORECAST AREA INTO THE GREAT LAKES. WITHIN THIS
TROUGH WAS AN UPPER LOW OVER EASTERN LAKE SUPERIOR...A SHORTWAVE
DROPPING SOUTH TOWARDS I-90 IN THE FORECAST AREA...AND ANOTHER
SHORTWAVE OVER NORTHEAST MN. COOL TEMPERATURES ALOFT REFLECTED BY
500MB TEMPS OF -27 TO -33C PER 12Z RAOBS...DAYTIME HEATING...NEAR
SATURATED CONDITIONS BETWEEN 700-850MB AND THE AFOREMENTIONED
SHORTWAVES HELPING TO PRODUCE PLENTY OF SHOWERS ACROSS THE
REGION....ESPECIALLY ALONG AND NORTH OF I-94. TEMPERATURES HAVE
STRUGGLED TO RISE WITH CLOUDS...PRECIP AND 850MB TEMPS OF -3 TO
-7C. READINGS HAVE ONLY CLIMBED INTO THE MID 30S TO LOW 40S. THE
COLD TEMPERATURES HAVE SUPPORTED A MIX OF RAIN AND SNOW...WITH THE
SNOW CONFINED MORESO TO HIGHER ELEVATIONS AND TAYLOR/CLARK
COUNTIES. ON TOP OF THE COOL AIR...A TIGHT PRESSURE GRADIENT AND
925MB WINDS OF 25-35 KT HAS RESULTED IN WINDS GUSTING TO THE 925MB
SPEEDS...MAKING IT FEEL FALL-LIKE. THESE WINDS ARE JUST BELOW
ADVISORY CRITERIA.
THE OVERALL UPPER PATTERN CHANGES LITTLE IN THE NEXT 24 HOURS WITH
ONLY A SLIGHT DRIFT EASTWARD OF THE UPPER LOW AND TROUGHING. THIS
SLIGHT DRIFT LOOKS TO BE ENOUGH SUCH THAT MUCH OF THE SHORTWAVE AND
INSTABILITY INDUCED SHOWERS ON WEDNESDAY WILL FALL EAST OF THE
FORECAST AREA. HOWEVER...PORTIONS OF TAYLOR AND ADAMS COULD GET
CLIPPED IN THE AFTERNOON. GETTING BACK TO TONIGHT...GENERAL MODEL
CONSENSUS SUGGESTS THE LOSS OF DAYTIME HEATING WILL ALLOW SHOWER
ACTIVITY TO BECOME MORE ISOLATED THROUGH THE EVENING...EVENTUALLY
ENDING BY MIDNIGHT.
CLOUDS LOOK TO HOLD OVER MUCH OF THE FORECAST AREA TONIGHT...AIDED
BY A SURGE OF 850MB MOISTURE CURRENTLY IN NORTHWEST ONTARIO DROPPING
SOUTHWARD WITH THE SHORTWAVE IN NORTHEAST MN. SUBSIDENCE IN THE WAKE
OF THIS SHORTWAVE...COMBINED WITH 925-700MB WINDS BACKING A BIT MORE
WESTERLY ON WEDNESDAY...WILL HELP TO RESULT IN MORE SUNSHINE.
DESPITE THE CLOUDS TONIGHT...AND A PERSISTENT BREEZE...TEMPERATURES
WILL STILL FALL AS THAT SHORTWAVE IN NORTHEAST MN DRAGS COLDER AIR
INTO THE FORECAST AREA. BY 12Z WED...850MB TEMPS ARE PROGGED TO DROP
TO -8 TO -11C...OR ALMOST 2 STANDARD DEVIATIONS BELOW NORMAL.
GUIDANCE LOWS IN THE MID 20S TO LOW 30S SEEM REASONABLE. HAVING MORE
SUNSHINE ON WEDNESDAY WILL HELP PRODUCE A WARMER DAY THAN
TODAY...ALBEIT STILL WELL BELOW NORMAL GIVEN 850MB TEMPS ONLY
CLIMBING TO -2 TO -7C BY 00Z THU. MOST LOCATIONS SHOULD CLIMB INTO
THE 40S...WITH LOW 50S LIKELY IN RIVER VALLEYS AND THE SOUTHWEST
PORTION OF THE FORECAST AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 326 PM CDT TUE APR 21 2015
THE UPPER FLOW PATTERN LOOKS TO BECOME MORE PROGRESSIVE THROUGH THE
END OF THE WEEK IN RESPONSE TO A DEEP UPPER TROUGH APPROACHING THE
PACIFIC NORTHWEST. THIS WILL HELP TO PUSH THE UPPER RIDGING AND
WARMER AIR OVER THE WESTERN U.S. TOWARDS THE FORECAST AREA. 850MB
TEMPS DO NOT CHANGE A WHOLE LOT WED NIGHT...BUT MORE IMPRESSIVE WARM
ADVECTION COMES IN FOR THU WITH 850MB TEMPS REACHING 0 TO -2C BY 00Z
FRI...AND 0 TO 4C BY 00Z SAT. LOW PRECIPITABLE WATER ON
THURSDAY...AROUND 0.1 INCHES...SHOULD HELP TO TANK DEWPOINTS AND
RESULTING RHS. COMBINED WITH A DRYING DAY ON WEDNESDAY AND A 10-15
MPH NORTHWEST BREEZE...FIRE WEATHER COULD BE A CONCERN. SEE FIRE
WEATHER SECTION BELOW.
FOR FRIDAY INTO SATURDAY...AN UPPER LOW CURRENTLY NEAR LOS ANGELES
IS PROGGED TO LIFT THROUGH THE CENTRAL PLAINS AND TRACK EASTWARD
ACROSS ILLINOIS. ALTHOUGH THIS TRACK IS SOUTH OF THE FORECAST
AREA...MOISTURE ADVECTION SPREADS NORTHWARD AHEAD OF THE UPPER LOW
TO HELP PRODUCE SOME RAIN. THE SPEED HAS SLOWED DOWN A BIT...AND AS
A RESULT DELAYED THE SPREADING OF CHANCES OF RAINFALL EASTWARD ON
FRIDAY. FURTHER DELAYS MAY BE NEEDED. RAIN CHANCES SPREAD ACROSS THE
FORECAST AREA FRIDAY NIGHT AND THEN SHIFT TO SOUTH OF I-90 ON
SATURDAY...RESULTING FROM EASTERLY FLOW DRAGGING MORE DRY AIR INTO
NORTHERN SECTIONS. OVERALL APPEARS TO BE A LIGHT RAIN...WITH THE
HEAVIER RAIN TO THE SOUTH TIED TO THE UPPER LOW FORCING.
DRIER WEATHER LOOKS TO FOLLOW SATURDAY NIGHT AND SUNDAY AS UPPER
RIDGING BUILDS BACK INTO THE FORECAST AREA FROM THE WEST.
TEMPERATURES SHOULD REBOUND CLOSER TO NORMAL AS WELL WITH MORE SUN
ON SUNDAY AND 850MB TEMPS IN THE 0-4C RANGE.
FOR EARLY NEXT WEEK UNCERTAINTY BEGINS TO INCREASE. NOT SO MUCH ON
THE UPPER PATTERN WHERE MODELS ADVERTISE TROUGHING DEVELOPING FROM
THE NORTHEAST U.S. INTO THE SOUTHEAST U.S....BUT WITH PRECIPITATION
CHANCES AS THIS TROUGH DEVELOPS. THE 21.12Z GFS HAS A SHORTWAVE
TROUGH DROPPING THROUGH THE REGION TO BRING PRECIPITATION TO THE
AREA. MEANWHILE THE 21.12Z ECMWF AND CANADIAN SUGGEST A DRY
PERIOD AS HIGH PRESSURE DOMINATES AT THE SURFACE...WITH THE
AFOREMENTIONED SHORTWAVE TROUGH FALLING APART. FOR NOW HAVE WENT
WITH THE CONSENSUS AND HAVE 20-30 PERCENT CHANCES. HOW THIS
SHORTWAVE TROUGH EVOLVES ALSO HAS AN IMPACT ON TEMPERATURES. IN
THE CASE OF THE 21.12Z GFS...IT SUGGESTS 850MB TEMPS PLUNGE TO
AROUND -4C BY 12Z TUE...ABOUT 8C COLDER THAN THE ECMWF. ALSO
FOLLOWED CONSENSUS HERE FOR NOW WITH TEMPS JUST SHY OF NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1200 AM CDT TUE APR 21 2015
A 5 TO 6K BROKEN DECK OF CLOUDS WILL PERSIST ACROSS THE AREA
THROUGH THE OVERNIGHT AND WEDNESDAY MORNING. SCATTERED SNOW
SHOWERS WILL PERSIST DURING THIS TIME PERIOD...BUT ANY VISIBILITIY
RESTRICTIONS WOULD ONLY LAST A FEW MINUTES AT MOST. AS DRIER AIR
MOVES INTO THE REGION AND THE FLOW BECOMES ANTICYCLONIC...EXPECT
SKIES TO QUICKLY CLEAR AT BOTH TAF SITES.
&&
.FIRE WEATHER...
ISSUED AT 326 PM CDT TUE APR 21 2015
AFTER SOME RECENT COOL/WET DAYS...CONDITIONS LOOK TO DRY OUT AGAIN
WEDNESDAY AND THURSDAY. RELATIVE HUMIDITIES ARE EXPECTED TO DROP
INTO THE 20S ON WEDNESDAY AND MAY EVEN DROP BELOW 20 PERCENT IN A
FEW SOUTHEAST MN LOCATIONS ON THURSDAY. FIGURE MUCH OF WEDNESDAY
WILL BE A DRYING DAY FOR FUELS GIVEN THE WET WEATHER...WITH A 15
TO 25 MPH NORTHWEST BREEZE AIDING IN THE DRYING. THEREFORE
THURSDAY WOULD APPEAR TO BE THE MORE CONCERNING DAY...THOUGH WINDS
LOOK LIGHTER IN THE 10 TO 15 MPH RANGE. NEVERTHELESS...WELL HAVE
TO KEEP A CLOSE EYE ON THURSDAY AND SEE TOO WHERE ALL THE
VEGETATION STANDS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1025 PM PDT THU APR 23 2015
.UPDATE...
A QUICK FORECAST UPDATE WILL BE SENT SHORTLY TO INCREASE POPS
NORTH OF I-80, AND EXTEND THUNDER INTO PARTS OF NORTHERN CA LATER
INTO THE NIGHT.
CLUSTER OF THUNDERSTORMS WITH IMPRESSIVE LIGHTNING OUTPUT WHICH
DEVELOPED OVER THE NORTHERN SACRAMENTO VALLEY EARLIER THIS EVENING
CONTINUE TO MARCH EAST, WITH STEADY PRECIP SPREADING MAINLY FROM
CENTRAL PLUMAS COUNTY SOUTH TO THE TAHOE BASIN. ALTHOUGH THE
LIGHTNING ACTIVITY SHOULD GRADUALLY DIMINISH OVERNIGHT, IT
APPEARS THAT SOME STRIKES SHOULD SPREAD ACROSS EASTERN PLUMAS AND
SIERRA COUNTIES SOUTHWARD TO THE NORTH AND WEST SHORES OF THE
TAHOE BASIN. IN THESE AREAS WE EXTENDED MENTION OF THUNDER THRU 2
AM.
SEVERAL RUNS OF THE HRRR HAVE SPREAD RAIN FROM THIS CONVECTIVE
CLUSTER INTO WESTERN NV MAINLY NORTH OF I-80 THRU THE OVERNIGHT
HOURS. IN THESE AREAS WE INCREASED SHOWER COVERAGE AND QPF VALUES,
WITH AMOUNTS RANGING FROM 0.10 TO 0.25 INCH OVERNIGHT. THE
HEAVIEST RAIN TOTALS ARE LIKELY ALONG AND WEST OF HIGHWAY 89 NORTH
OF TRUCKEE, WHERE LOCAL AMOUNTS UP TO 0.50 INCH ARE POSSIBLE. MJD
&&
.PREVIOUS DISCUSSION... /ISSUED 215 PM PDT THU APR 23 2015/
SYNOPSIS...
LOW PRESSURE WILL DOMINATE THROUGH SATURDAY WITH CHANCES FOR RAIN
AND HIGH ELEVATION SNOW ALONG WITH BREEZY CONDITIONS. THE BEST
CHANCE OF RAIN AND SNOW WILL ARRIVE LATE FRIDAY NIGHT INTO SATURDAY
MORNING WITH POTENTIAL TRAVEL PROBLEMS IN THE SIERRA AND NORTHEAST
CALIFORNIA. HIGH PRESSURE WILL BUILD EARLY NEXT WEEK WITH DRY AND
WARMER WEATHER.
SHORT TERM...
LATEST SATELLITE TRENDS AND SURFACE OBSERVATIONS/WEB CAMS INDICATE
THAT CONVECTIVE DEVELOPMENT HAS BEEN RATHER FLAT THIS AFTERNOON.
MUCH OF THE SHOWER ACTIVITY SO FAR HAS DEVELOPED WEST OF THE CREST
WITH RADAR INDICATING ISOLATED SHOWERS EAST OF THE SIERRA. MODELS
CONTINUE TO SHOW BEST OPPORTUNITY FOR SHOWERS AND ISOLATED THUNDER
SOUTH OF HIGHWAY 50 LATE THIS AFTERNOON INTO THE EVENING.
OTHERWISE ATTENTION TURNS TO DEVELOPING TROUGH ALONG THE WEST
COAST FRI-SAT AS MODELS HAVE TRENDED SIGNIFICANTLY MORE AMPLIFIED.
12Z MODEL RUNS CONTINUED THE TREND OF THE PREVIOUS FEW RUNS IN
DROPPING TROUGH SOUTHWARD WITH AXIS FARTHER WEST WHICH WOULD PUT
THE SIERRA AND WESTERN NV IN A BETTER POSITION FOR AN ACTIVE
WEATHER PATTERN. A LEAD SHORTWAVE WILL PUSH SOUTHEASTWARD ACROSS
THE INTERMOUNTAIN WEST TONIGHT AND EARLY FRIDAY, WHICH WILL PUSH A
COLD FRONT SOUTHWARD INTO NORTHERN CA-NORTHERN NV WHERE IT WILL
STALL AND WEAKEN DURING THE DAY FRIDAY. MOISTURE AND DYNAMICS
SHOULD BE SUFFICIENT LATE TONIGHT INTO FRIDAY MORNING FOR A BAND
OF SHOWERS TO WORK ACROSS NORTHERN AREAS, MAINLY NORTH OF I-80
WITH SOME QPF AMOUNTS APPROACHING A COUPLE TENTHS NEAR THE OREGON
BORDER VICINITY OF FRONT. OTHERWISE, SHOWERS WILL BE MORE ISOLATED
WITH BREEZY CONDITIONS DEVELOPING BY FRIDAY AFTERNOON. LOCAL GUSTS
TO 40 MPH ARE POSSIBLE AND AREA LAKE WATERS WILL BE CHOPPY. THE
BREEZY WEST GRADIENT IS USUALLY UNFAVORABLE FOR DEEP CONVECTION
AND THUS WE REMOVED THUNDERSTORM WORDING DESPITE MODEL SOUNDING
INSTABILITY.
THE MAIN TROUGH DROPS SOUTHWARD FRI NIGHT AND PUSHES SOUTHEASTWARD
THROUGH THE AREA SATURDAY WITH A BETTER CHANCE OF MOUNTAIN SNOW
AND VALLEY RAIN ALONG WITH ANOTHER BREEZY DAY SATURDAY. THE BIG
QUESTION WILL BE QPF AND SNOW AMOUNTS AS MODELS STILL SHOW SOME
VARIATION IN THE AMPLITUDE AND RESULTANT SPEED OF SYSTEM AS IT
TRACKS THROUGH CA-NV. THE GFS/NAM ARE SLOWER OVERALL AND SHOW
1-1.5 INCHES OF QPF ALONG THE SIERRA WHICH WOULD AMOUNT TO 12-18
INCHES OF SNOW FOR THE HIGH SIERRA FROM THE TAHOE BASIN SOUTH INTO
MONO COUNTY, WITH SEVERAL INCHES OF SNOW AT LAKE LEVEL AND FOR
PASSES IN NORTHEAST CA. ON THE OTHER END OF THE SPECTRUM IS THE
ECMWF WHICH STILL SHOWS A SIMILAR STORM TRACK ALTHOUGH FASTER AND
WITH QPF ON THE ORDER OF HALF AN INCH. ALL THREE MODELS CONTINUE
TO PICK UP ON A PWAT PLUME OF 1+ INCH WHICH GETS INGESTED INTO THE
SYSTEM AS IT WORKS SOUTHWARD ALONG THE SIERRA. THIS WOULD TEND TO
FAVOR THE WETTER SOLUTIONS.
DUE TO MEDIUM CONFIDENCE IN QPF, WE HAVE INTRODUCED A FORECAST IN
THE MIDDLE OF THE ROAD WHICH PUTS 6 TO 12 INCHES OF SNOW ALONG THE
CREST AND A FEW INCHES DOWN TO ABOUT 5500 FEET. TRAVEL IMPACTS ARE
MOST LIKELY LATE FRIDAY NIGHT AND SATURDAY MORNING. DIMINISHING
SNOW RATES AND HIGH SUN ANGLE SHOULD HELP MITIGATE ROAD IMPACTS
DURING THE AFTERNOON. FOR LOWER ELEVATIONS, SPILLOVER SHOULD BE
DECENT BUT WILL DEPEND ON SPEED OF SYSTEM.
A COOL AND DRIER NORTHERLY FLOW WILL FOLLOW SAT NIGHT INTO SUNDAY
WITH TEMPERATURES THIS WEEKEND ACTUALLY STAYING BELOW NORMAL.
HOHMANN
LONG TERM...MONDAY THROUGH THURSDAY...
MODELS STILL IN GOOD AGREEMENT WITH A MODERATE TO STRONG AMPLITUDE
RIDGE BUILDING IN EARLY NEXT WEEK BRINGING DRY CONDITIONS, MOSTLY
CLEAR SKIES AND AFTERNOON TEMPERATURES WARMING TO WELL ABOVE AVERAGE
BY TUESDAY. HIGHS EXPECTED TO BE IN THE UPPER 70S TO MID 80S FOR
WESTERN NEVADA VALLEYS AND THE UPPER 60S TO MID 70S FOR THE SIERRA
VALLEYS TUESDAY AND WEDNESDAY.
THE RIDGE LOOKS TO FLATTEN SOMEWHAT WEDNESDAY AND THURSDAY AS ENERGY
MOVES THROUGH THE PACIFIC NORTHWEST. THIS WILL BRING SOME INCREASE
IN AFTERNOON AND EVENING ZEPHYR-LIKE BREEZES ALONG WITH A SLIGHT
COOL DOWN BY THURSDAY (ALTHOUGH HIGHS WILL REMAIN CONSIDERABLY ABOVE
AVERAGE). SNYDER
AVIATION...
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED INTO THIS
EVENING, FOCUSED SOUTH OF HIGHWAY 50. LOCAL HIGHER TERRAIN
OBSCURATION IN HEAVIER SHOWERS AS WELL AS THUNDERSTORMS, WITH SMALL
HAIL AND OUTFLOW GUSTS TO 30 KTS POSSIBLE IN ALL STORMS. NORTH OF
I-80, DRIER AIR HAS WORKED IN WITH ONLY ISOLATED SHOWERS EXPECTED.
FOR TONIGHT SOME SHOWERS TO REDEVELOP AFTER 11 PM (06Z FRIDAY) WITH
OCCASIONAL MVFR CIGS POSSIBLE, MAINLY NORTH OF I-80.
A WETTER LATE FRIDAY NIGHT AND SATURDAY MORNING IS STILL ON TRACK.
WIDESPREAD TERRAIN OBSCURATION FOR SIERRA AND NORTHEAST CALIFORNIA
CAN BE EXPECTED, WITH SUB-LANDING MINIMUMS POSSIBLE FOR KTRK AND
LIKELY FOR KTVL THROUGH SATURDAY MORNING. ALSO, MINOR ACCUMULATIONS
POSSIBLE ON RUNWAYS FOR KTRK/KTVL. OUT INTO WESTERN NEVADA, RAIN
IS EXPECTED FOR LOWER VALLEY TERMINALS WITH THE MAIN IMPACTS BEING
HIGHER TERRAIN OBSCURATION, PERIODIC MVFR CIGS AND LEE OF THE
SIERRA TURBULENCE. SNYDER
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR PYRAMID
LAKE IN NVZ004.
LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR LAKE TAHOE
IN NVZ002.
CA...LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR LAKE TAHOE
IN CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
426 AM EDT FRI APR 24 2015
.SHORT TERM...COLD FRONT LOCATED ACROSS THE CENTRAL PORTIONS OF THE
AREA EARLY THIS MORNING...ORIENTED SW TO NE FROM THE NE GULF TO THE
ATLC COASTAL WATERS WILL CONTINUE TO DROP SWD AND MOVE INTO N
CENTRAL FL BY MID MORNING. SOME PATCHY FOG/LOW STRATUS WILL BE
POSSIBLE OVER THE COURSE OF THE NEXT FEW HOURS OVER THE I-75
CORRIDOR BUT SCT-BROKEN MID DECK CLOUDS MAY KEEP VSBY FROM GOING
MUCH BELOW 1-2 MILES. A SURGE OF NELY WINDS WILL OCCUR BEHIND THIS
BOUNDARY WITH OVERALL DRIER AIRMASS ADVECTING IN...ESPECIALLY ACROSS
OUR NRN AND NW ZONES. NIL POPS TODAY...WITH SKIES PARTLY CLOUDY.
TEMPS COOLER THAN YESTERDAY WITH HIGHS IN THE UPPER 70S N ZONES TO
MID 80S SW ZONES. BREEZY NELY WINDS AT THE COAST/BEACHES AROUND 15-
20G30MPH AT TIMES. THE BREEZY ONSHORE WINDS SHOULD DIMINISH
BY 5-6 PM.
TONIGHT...COLD FRONT THAT DROPS INTO CENTRAL FL TODAY STALLS TO OUR
S THEN BEGINS TO MAKE A NWD PUSH BY THE EARLY MORNING HOURS WITH
SKY COVER INCREASING WITH ISENTROPIC LIFT DEVELOPING RAPIDLY AFTER
06Z. MINS FCST IN THE UPPER 50S TO MID 60S. HAVE TRIMMED BACK POPS
TO LESS THAN 15 PERCENT BASED ON LATEST GUIDANCE...BUT CAN`T RULE
OUT A FEW SPRINKLES ACROSS WRN ZONES AS ISENTROPIC ASCENT INCREASES.
.SHORT TERM (SATURDAY THROUGH SUNDAY NIGHT)...
TROUGHING ALOFT WILL MIGRATE EASTWARD ACROSS THE PLAINS STATES AND
THE UPPER MIDWEST ON SATURDAY...REACHING THE OHIO VALLEY SATURDAY
NIGHT. MEANWHILE...RIDGING ALOFT WILL REMAIN CENTERED OVER THE
NORTHWESTERN CARIBBEAN...RESULTING IN STRENGTHENING WESTERLY FLOW
OVER OUR REGION. A WARM FRONT WILL LIFT NORTHWARD INTO SOUTHEAST GA
ON SATURDAY MORNING...WITH STRENGTHENING ISENTROPIC LIFT NORTH OF
THIS BOUNDARY POSSIBLY DEVELOPING A FEW SHOWERS ON SATURDAY MORNING
NEAR THE ALTAMAHA RIVER. OUR AREA WILL THEN BE LOCATED IN THE WARM
SECTOR WELL IN ADVANCE OF A COLD FRONT THAT WILL BE SWEEPING THROUGH
THE LOWER MISSISSIPPI VALLEY. SHORTWAVE ENERGY IS PROGGED TO MOVE
INTO SOUTHEAST GA FROM THE WEST DURING THE AFTERNOON HOURS ON
SATURDAY...WHICH SHOULD IGNITE AT LEAST SCATTERED AFTERNOON
CONVECTION OVER INLAND SOUTHEAST GA AND THE SUWANNEE
VALLEY...WITH THE GULF COAST SEA BREEZE BEING THE LIKELY TRIGGER
MECHANISM IN FL. CONVECTIVE ACTIVITY WILL BECOME WIDESPREAD OVER
SOUTHEAST GA BY LATE AFTERNOON...WITH LIKELY POPS FOR COASTAL
NORTHEAST FL AS ACTIVITY ENCOUNTERS A PINNED ATLANTIC SEA BREEZE
DURING THE LATE AFTERNOON. LESS ACTIVITY IS EXPECTED FOR
LOCATIONS SOUTH OF GAINESVILLE/ST. AUGUSTINE AS MID-LEVEL DRY AIR
ADVECTS OVERHEAD FROM THE NORTHEASTERN GULF. MODEL SOUNDINGS DEPICT
A STRENGTHENING LOW-LEVEL VEERING PROFILE AND MARGINAL
INSTABILITY...WITH CAPES OF 1000-1500 J/KG AND 500 MB TEMPS AROUND -
9 CELSIUS. GIVEN THESE VARIABLES AND STRENGTHENING SW/W WINDS
JUST OFF THE SURFACE...THE STORM PREDICTION CENTER HAS PLACED AREAS
ALONG AND NORTH OF INTERSTATE 10 WITHIN A SLIGHT RISK FOR SEVERE
THUNDERSTORM DEVELOPMENT ON SATURDAY AFTERNOON...WITH A MARGINAL
RISK FOR THE REST OF NORTHEAST AND NORTH CENTRAL FL. HIGHS WILL
CLIMB INTO THE 80S. STRONG DOWNBURST WINDS AND HAIL APPEAR TO BE THE
PRIMARY HAZARDS THROUGH SUNSET BEFORE ACTIVITY MOVES OFFSHORE.
STRONG W/SW FLOW WILL PERSIST ON SATURDAY NIGHT AND SUNDAY LOCALLY.
THIS MAY DEVELOP AN EARLY MORNING CONVECTIVE COMPLEX OVER THE
NORTHEAST GULF OF MEXICO THAT MAY MOVE ONSHORE INTO THE SUWANNEE
VALLEY ON SUNDAY MORNING. ABOVE NORMAL LOWS ARE EXPECTED...WITH
UPPER 60S TO LOWER 70S. EXPECT ANOTHER SEASONABLY WARM DAY REGION-
WIDE...WITH SCATTERED AFTERNOON CONVECTION OVER NORTHEAST AND NORTH
CENTRAL FL DEVELOPING ALONG THE GULF COAST SEA BREEZE. DRY AIR ALOFT
WILL SINK SOUTHWARD INTO SOUTHEAST GA AS TROUGHING ALOFT DIGS
SOUTHWARD OVER THE MID-ATLANTIC STATES...LIMITING CONVECTIVE
COVERAGE FOR LOCATIONS NORTH OF WAYCROSS TO BRUNSWICK. A FEW STRONG
TO SEVERE THUNDERSTORMS WILL BE POSSIBLE OVER FL...WHERE MODEL
SOUNDINGS DEPICT A VERY UNSTABLE ATMOSPHERE. HOWEVER...OVERALL
FORCING IS QUESTIONABLE...AND THUS DECIDED TO USE SCATTERED
COVERAGE. THE STORM PREDICTION CENTER HAS PLACED OUR REGION WITHIN A
MARGINAL RISK FOR SEVERE THUNDERSTORM DEVELOPMENT ON SUNDAY.
STRONG OFFSHORE FLOW WILL BOOST HIGHS TO THE 85-90 RANGE REGION-
WIDE. A COLD FRONT WILL THEN SINK SOUTHWARD THROUGH OUR REGION ON
SUNDAY NIGHT...WITH CONVECTION CONCLUDING DURING THE EARLY EVENING
HOURS. LOWS WILL RANGE FROM THE MID 60S NORTH TO THE LOWER 70S OVER
NORTH CENTRAL FL.
.LONG TERM (MONDAY THROUGH FRIDAY)...
A POTENT SHORTWAVE TROUGH WILL EMERGE FROM THE DESERT SOUTHWEST
EARLY MONDAY. THIS FEATURE WILL MOVE EASTWARD ACROSS THE DEEP SOUTH
THROUGH MIDWEEK. THE COLD FRONT THAT MOVES THROUGH OUR REGION ON
SUNDAY NIGHT WILL STALL OVER CENTRAL FL MONDAY...AND THEN WILL
RETREAT NORTHWARD AS A WARM FRONT ON TUESDAY. EXPECT WIDELY
SCATTERED AFTERNOON CONVECTION OVER MAINLY INLAND LOCATIONS OF
NORTHEAST AND NORTH CENTRAL FL MONDAY...WITH A DRY AIR MASS IN
SOUTHEAST GA EXPECTED TO KEEP THINGS DRY. HIGHS WILL RANGE FROM THE
MID 70S AT THE COAST DUE TO DEVELOPING ONSHORE FLOW TO THE LOWER 80S
IN NORTH CENTRAL FL. SCATTERED CONVECTION WILL BE POSSIBLE OVER FL
ON MONDAY NIGHT AS THE FRONT BEGINS TO RETREAT NORTHWARD...WITH DRY
CONDITIONS CONTINUING IN SOUTHEAST GA. LOWS WILL RANGE FROM NEAR 60
FOR INTERIOR SOUTHEAST GA TO THE MID/UPPER 60S IN FL. LIKELY POPS
ARE EXPECTED TUES AND TUES NIGHT AS THE WARM FRONT AND SHORTWAVE
ENERGY MIGRATE THROUGH OUR AREA. DEPENDING ON THE STRENGTH OF
SHORTWAVE ENERGY...STRONG TO SEVERE CONVECTION IS POSSIBLE ALONG THE
WARM FRONT TUES AND ALONG A COLD FRONT/STRENGTHENING SURFACE LOW
WED. HIGHS BOTH DAYS WILL RANGE FROM 75-80...WITH LOWS IN THE 60S. A
SLIGHTLY COOLER AND MUCH DRIER AIR MASS WILL PLUNGE INTO OUR REGION
LATE NEXT WEEK...WITH HIGHS GENERALLY IN THE 70S AND LOWS FALLING TO
THE 55-60 RANGE.
&&
.AVIATION...PREVAILING VFR WITH POSSIBILITY OF MVFR VSBY/LOW STRATUS
FOR A BRIEF TIME AT GNV EARLY THIS MORNING. OTHERWISE...WINDS WILL
SHIFT AROUND TO N EARLY THEN NE BY MID MORNING. STRONGER NE WINDS
FOR SSI...CRG...SGJ...JAX AND VQQ TERMINALS UP AROUND 12-15G20KT
THEN WEAKENING BY THIS EVENING AND TURNING E TO SE OVERNIGHT AT 10
KT OR LESS.
&&
.MARINE...W TO NW WINDS 10 KT OR LESS EARLY THIS MORNING WILL
BECOMING STRONGER OUT OF THE TO N TO NE BEHIND EARLY COLD
FRONTAL PASSAGE. HIGH-RES MODEL GUIDANCE AND BUOYS SHOW WE WILL
LIKELY REACH SCA CONDITIONS FOR ABOUT A 4-8 HOUR PERIOD TODAY SO
HOISTED SCA FOR THE NRN WATERS TIL 4 PM TODAY THOUGH COULD BE
SLIGHTLY EARLIER BASED ON LATEST RAP MODEL. SEAS FCST TO BUILD TO
ABOUT 4-6 FT BY MID DAY. FOR SRN WATERS S OF THE ST AUGUSTINE SCEC
HEADLINE WILL SUFFICE. WINDS WILL INCREASE ON SATURDAY AND SATURDAY
NIGHT VEERING FROM SOUTHERLY TO WESTERLY AS NEXT STORM SYSTEM PASSES
TO OUR N. NEXT COLD FRONT MOVES INTO THE AREA WATERS EARLY MONDAY
MORNING...STALLING MONDAY NIGHT OVER CENTRAL FL. A SFC LOW PRESSURE
APPROACHES FROM THE W ON TUESDAY.
RIP CURRENTS: MODERATE RISK AS SURF BUILDS TODAY. LOW TO MODERATE
RISK FOR SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 78 59 82 68 / 10 10 70 40
SSI 71 63 79 70 / 0 10 60 40
JAX 76 63 85 70 / 0 10 60 40
SGJ 74 67 85 71 / 10 10 50 20
GNV 82 63 87 71 / 10 10 40 20
OCF 86 65 86 71 / 10 10 30 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 4 PM EDT THIS
AFTERNOON FOR COASTAL WATERS FROM ALTAMAHA SOUND TO
FERNANDINA BEACH FL OUT 20 NM-COASTAL WATERS FROM
FERNANDINA BEACH TO ST. AUGUSTINE FL OUT 20 NM-WATERS FROM
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL FROM 20 TO 60 NM-
WATERS FROM FERNANDINA BEACH TO ST. AUGUSTINE FL FROM 20 TO
60 NM.
&&
$$
SHASHY/NELSON
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
339 AM EDT FRI APR 24 2015
.DISCUSSION...
THE TAIL END OF A FRONTAL TROUGH PASSING OFFSHORE THE SE STATES
WILL PASS OVER ECFL WITH LITTLE FANFARE DURING THIS MORNING. LOCAL
WINDS WILL RESPOND BY VEERING FROM WLY COMPONENT AT DAYBREAK TO
NORTH THEN NORTHEAST DURING THE AFTERNOON AS HIGH PRESSURE BUILDS
INTO THE AREA BEHIND THE DEPARTING BOUNDARY. AN APPROACHING RIDGE
EMBEDDED WITHIN THE PROGRESSIVE WLYS WL BRING WARM CONDS IN THE
MID TO UPR 80S ACROSS THE BULK OF THE AREA. RECENT HRRR GUID
SUPPORTED BY GFS MOS SHOWS A SMALL RAIN CHC ALONG THE SPACE CST
AND TREASURE CST TO LAKE OKEE DURING THE HEAT OF THE AFTERNOON AS
THE ONSHORE WINDS COMBINES WITH SFC HEATING AND SOME MODEST
MOISTURE TO CREATE ISOLD SHOWERS AND A FAST MOVING STORM OR TWO.
PRECIP CHCS WL RANGE FROM UNMENTIONED WEST OF THE I-4 CORRIDOR TO
AROUND 20 PERCENT ACROSS THE SOUTH. RAIN CHCS LARGELY TIED TO SFC
HEATING AND BOUNDARY INTERACTION WL DIMINISH AFTER NIGHTFALL. LOWS
WILL MAKE IT TO THE UPR 60S TO AROUND 70.
SAT...SURFACE HIGH CONTINUES TO SLIDE AWAY FROM THE SOUTHEAST COAST
INTO THE ATLANTIC AS THE NEXT SYSTEM MOVES ACROSS THE OH/TN VALLEYS
AND OFF THE CAROLINA COAST INTO LATE WEEKEND.
WHILE MODELS SHOW OVERALL MOISTURE WILL BE SUFFICIENT FOR SCATTERED
SHOWERS AND STORMS WITH PWATS 1.6-18"...FORECAST SOUNDINGS SHOW SOME
DRIER AIR LINGERING IN THE 850-500MB LEVEL...ESPECIALLY ON
SAT...WHICH MAY HELP DELAY CONVECTIVE ONSET UNTIL LATER IN THE
AFTERNOON. HOWEVER ANY LINGERING DRY AIR WILL ENHANCE THE WIND
THREAT FROM STRONG STORMS ESPECIALLY GIVEN THE MID LAYER WESTERLY
FLOW OF 45-55 KNOTS WITH WINDS EVEN IN THE 925-850MB LAYER
APPROACHING 30KTS.
SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER
A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS THE
MAIN HAZARD GIVEN THE BRISK STORM MOTION. A FEW ROTATING STORMS WILL
NOT BE OUT OF THE QUESTION ESPECIALLY NEAR THE COAST AS MODELS HINT
AT THE EAST COAST SEA BREEZE BOUNDARY TRYING TO FORM RIGHT ALONG THE
IMMEDIATE COAST LATE IN THE DAY.
ISOLATED SHOWERS POSSIBLE TOWARDS DAYBREAK SUNDAY AS THE FRONT EDGES
A LITTLE FURTHER SOUTH AND WEST FLOW INCREASES...BRINGING SOME
ACTIVITY FROM OFF THE GULF ACROSS THE PENINSULA.
TEMPERATURES CONTINUE ABOVE NORMAL IN THE UPPER 80S AND LOW 90S WITH
LOWS IN THE 70S.
SUNDAY...WEAK FRONTAL BOUNDARY DROPS INTO N FLORIDA WITH LITTLE
SOUTHWARD PROGRESS INTO SUNDAY EVENING. THERE WILL BE A LITTLE
BETTER MOISTENING IN THE MID LEVEL GIVEN THE CLOSER PROXIMITY OF THE
FRONT WITH BRISK WESTERLY FLOW INCREASING AS SPEEDS AT 925MB COME UP
TO 20-30 KNOTS AND 50-55 KNOTS AT 500MB.
GIVEN THE STRENGTH OF THE FLOW...NO SEABREEZE DEVELOPMENT IS
EXPECTED AND TEMPS WILL BE A FEW DEGREES WARMER...GENERALLY AROUND
90 OR LOW 90S IN MOST LOCATIONS.
EXPECT AN EARLY START TO CONVECTION WITH STORMS PROGRESSING QUICKLY
FROM WEST TO EAST ACROSS E CENTRAL FL IN THE LATE MORNING AND
AFTERNOON HOURS. AS WITH SATURDAY...SPC HAS THE AREA FROM BREVARD
AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX
WITH ISOLATED SEVERE WIND GUSTS CONTINUING TO BE THE MAIN HAZARD.
THE PROXIMITY OF THE FRONT AND BRISK FLOW MAY ALLOW AND GULF
ACTIVITY OVERNIGHT TO CONTINUE TO MOVE ACROSS THE PENINSULA...MAINLY
IN THE FORM OF SHOWERS.
MON-THURS...UNSETTLED PATTERN FOR THE FIRST HALF OF THE WEEK AS THE
WEEKEND`S FRONTAL BOUNDARY MEANDERS DOWN THE PENINSULA DURING THE
DAY ON MONDAY BEFORE STALLING/WASHING OUT ACROSS S FLORIDA LATE IN
THE DAY. ROBUST UPPER LEVEL LOW THAT MOVES INTO THE SOUTHERN PLAINS
ON MONDAY WILL SLOWLY PHASE WITH A NORTHERN STREAM SHORTWAVE AS IT
MOVES INTO THE EASTERN US WEDNESDAY AND THURSDAY.
AT THE SURFACE...WEAK BOUNDARY LIFTS BACK NORTH INTO TUESDAY AS
130KT JET SLIDING ACROSS THE NORTHERN GULF OF MEXICO HELPS SPAWN AN
ASSOCIATED SURFACE LOW THAT TRACKS ACROSS N FLORIDA/GA LATE
WEDNESDAY OR THURSDAY. WHILE THE GFS AND ECMWF SHOW THE SAME BROAD
SOLUTION...SOME DIFFERENCES IN TIMING AND EVOLUTION OF THE UPPER
LEVEL FEATURES TRANSLATE INTO LARGER DIFFERENCES IN THE STRENGTH OF
THE SURFACE LOW.
GFS HAS SWUNG BACK TOWARDS A DRIER SOLUTION ON MONDAY...BUT WILL
KEEP WITH PREVIOUS RUNS AND KEEP SCT POPS IN THE FORECAST WITH
ACTIVITY FOCUSED TOWARDS THE FAR WESTERN INTERIOR...OKEECHOBEE AND
TREASURE COAST GIVEN THE LOW LEVEL NE PUSH THAT OCCURS BEHIND THE
BOUNDARY.
CONSENSUS BETWEEN GFS AND ECMWF STILL KEEP 40-60 PERCENT POPS IN THE
FORECAST FOR TUES AND WED AS WEST-SOUTHWEST FLOW TAPS INTO
SUBTROPICAL MOISTURE AND PWATS COME UP TO CLOSE TO 2". WIND FIELDS
WILL SUPPORT A FEW BREEZY DAYS DURING THE PERIOD WITH THE POSSIBILITY
FOR SOME GUSTY STORMS AS WELL.
SURFACE LOW PULLS OUT INTO THE ATLANTIC WED NIGHT AND FRONT MOVING
THROUGH THE REGION. A FEW SHOWERS MAY LINGER DEPENDING ON THE SPEED
OF THE FRONT INTO THURSDAY.
&&
.AVIATION...
COTD VFR CONDS THE NEXT 24H OVER MOST SITES WITH EXCEPTION OF
SOME PSBL CIGS NR FL 040 AND ISOLD SHRA FM VRB-FPR-SUA-OKE. FM
24/15Z-24/22Z.
&&
.MARINE...
TODAY AND TONIGHT...PSG OF THE FRONTAL TROUGH OVER THE WATERS THIS
AM WI BRING CHANGING WIND CONDS FROM MORNING INTO THE AFTERNOON.
MAIN CONCERN WL BE DEVELOPING NLY TO ONSHORE WIND DURING AFTERNOON
WHICH WL INCREASE WAVE HGHTS ALONG WITH BRINGING A WIND CHOP TO
LCL WATERS. HEADLINES ARE NOT ANTICIPATED ATTM...HOWEVER SEA STATE
WL BEGIN TO RAMP UP ONCE THE NLYS BEHIND THE FRONTAL TROUGH MOVES
INTO THE AREA THIS AFTERNOON.
SAT-SUN...S/SW WINDS WILL INCREASE TO 15-20 KNOTS SAT AFTERNOON AS
GRADIENT INCREASES BETWEEN DEPARTING SURFACE HIGH AND SYSTEM MOVING
ACROSS OH/TN VALLEYS. WINDS VEER MORE W/SW INTO SUNDAY AS FRONT
DROPS INTO NORTH FLORIDA WITH WINDS CONTINUING 15-20KTS. SEAS WILL
INCREASE UP TO 4-5 FT OFFSHORE INTO SUNDAY WITH PERIODS SHORTENING
DUE TO THE SHORT FETCH. BOATERS SHOULD BE PREPARED FOR SCATTERED
STRONG STORMS APPROACHING FROM THE WEST QUICKLY THIS WEEKEND.
MON-WED...FRONT SLIDES THROUGH LATE ON MONDAY WITH WINDS VEERING
NORTH THEN NORTHEAST 10-15KTS. BOUNDARY LIFTS BACK INTO REGION INTO
TUESDAY WITH WINDS VEERING EAST-SOUTHEAST...THEN INCREASING OUT OF
THE SOUTH-SOUTHWEST LATE ON WEDNESDAY AS SURFACE LOW IS FORECASTED
TO TRACK ACROSS NORTH FLORIDA. POTENTIAL WILL REMAIN FOR SCATTERED
OFFSHORE MOVING STRONG STORMS INTO MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 80 68 85 72 / 10 10 30 20
MCO 86 70 87 71 / 10 10 30 10
MLB 82 71 87 72 / 20 10 30 20
VRB 82 69 87 72 / 20 10 20 10
LEE 86 70 84 73 / 10 10 30 20
SFB 84 69 86 74 / 10 10 30 20
ORL 85 70 86 72 / 10 10 30 20
FPR 84 69 88 71 / 20 10 20 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...PENDERGRAST
LONG TERM....MOSES
AREA FORECAST DISCUSSION
NWS TOPEKA KS
353 AM CDT Fri Apr 24 2015
.SHORT TERM...(Today and Tonight)
Issued at 353 AM CDT FRI APR 24 2015
Upper trough was located over Arizona this morning at 08Z while a
weak low pressure tough was located in the lee of the Rockies. Water
Vapor loop shows a fetch of moisture extending from the eastern
Pacific into the the Central Plains this morning. Low level jet was
advecting moisture northward across central Kansas with dew points
in the 50s. Expect an increase in low level moisture through the
morning hours with low level jet veering to the south southwest.
Models are in agreement with the progression of the upper trough
into the western Kansas by 00Z then ejecting northeast into
northeast Kansas tonight increasing forcing for ascent this evening
for convection. The surface low follows a similar track from
southwest Kansas into north central and northeast Kansas by late
evening. a dry line front will extend south from the low with a warm
front lifting northward across the area with much of the area south
of I-70 in the warm sector. Initial showers with isolated
thunderstorms are possible this morning on the nose of the
warm/moisture advection and isentropic lift. Expect a period of
little activity from late morning through mid/late afternoon. Later
this afternoon expect showers and thunderstorms to develop out in
southwest Kansas and into central Kansas then spreading northeast
through the evening hours. All of northeast Kansas will have a
chance for severe weather from late afternoon into the overnight
hours. All modes of severe weather will be possible with large hail,
damaging winds and a few tornadoes possible. Soundings show storms
remaining surfaced based through much of the evening hours, with
backed low level winds and 0-1km helicity of 200-300 m^2/s^2 in the
warm sector as well as along the warm front so the tornado threat
will likely continue after dark. Threat of storms will diminish
gradually after midnight with the passage of the upper trough. Highs
today will range from the mid 60s to lower 70s. Lows tonight in the
50s.
.LONG TERM...(Saturday through Thursday)
Issued at 353 AM CDT FRI APR 24 2015
Upper trough`s exit across northern Missouri brings a gradual end
to precip Saturday. Cold air advection on north to northeast
winds behind the system brings a modest boundary south through the
area in the afternoon, though meager moisture and rising heights
preclude any mention of convection. Weak high pressure to the
north and a deepening low over the Southwest keeps east winds in
place for Sunday. Cloud cover looks rather prevalent for the
morning but mixing deep enough to still realize highs in the lower
60s. Still appears the upstream system will stay south of the area
into the work week, but at this point will keep small PoPs in the
south Sunday night into Monday night. Western ConUS/Rockies
ridging dominates conditions through the end of the forecast for
high confidence in dry weather. Main challenge should be
temperatures with still some influence of eastern Canadian trough
not far away, but moderation is likely for at least Tuesday and
Wednesday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1142 PM CDT THU APR 23 2015
Forecast seems to be on track, so there are not a lot of changes
to the prev forecast. Still looks like there is a chance for
elevated showers and thunderstorms with it being tough to pin
point timing and location. Therefore continue with VCTS. There is
a little more uncertainty in how long MVFR CIGS hang in through
the day Friday. With the RAP starting to show similar solutions to
the NAM, have held onto the CIGS into the afternoon. Don`t have
much confidence in the MOS guidance indicating IFR CIGS, but it is
not out of the question. As for stronger storms, models have the
best forcing moving through between 00Z and 06Z. TS coverage may
end up being more scattered, but feel PROBs are good enough to
include a TEMPO. There will likely need to be refinements to the
forecast as the weather moves in.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...65
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
258 AM CDT FRI APR 24 2015
...UPDATED LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 342 PM CDT THU APR 23 2015
FORECAST ISSUES IN THE SHORT TERM CENTER AROUND THUNDERSTORM CHANCES
TONIGHT AND FRIDAY AND THE SEVERE WEATHER POTENTIAL ASSOCIATED WITH
THE STORMS.
THE ATMOSPHERE OVER THE HIGH PLAINS OF EASTERN COLORADO AND FAR WESTERN
KANSAS WAS BECOMING MODERATELY UNSTABLE WITH DAYTIME HEATING THIS
AFTERNOON. A SURFACE TROUGH OF LOW PRESSURE STRENGTHENING OVER EASTERN
COLORADO WAS ALSO PROVIDING SOME LOW LEVEL CONVERGENCE AND TRIGGERING
WIDELY SCATTERED THUNDERSTORMS. SPC MESOANALYSIS SHOWS 30- 40 KNOTS
OF SHEAR IN THE 0-6 KM LAYER BUT ABOVE THIS LAYER, STRONGER SHEAR
WAS IN PLACE IN THE PRESENCE OF A STRONG SUBTROPICAL JET. THE STORMS
OVER EASTERN COLORADO WILL BE IN A FAVORABLE ENVIRONMENT TO BECOME
ROTATING SUPERCELLS. GIVEN THE STRONG EVACUATION ALOFT, LARGE HAIL
WILL BE A GOOD POSSIBILITY. THE HRRR MODEL HAS BEEN VERY CONSISTENT
WITH THUNDERSTORMS MOVING INTO WESTERN KANSAS AROUND JOHNSON AND
SYRACUSE AND POINTS NORTH THIS EVENING AROUND 23Z-01Z AND HAVE
KEPT THE BEST CHANCES IN THAT AREA EARLY THIS EVENING. AS THE
NIGHT CONTINUES, AN AREA OF THUNDERSTORMS COULD CONTINUE TO DEVELOP
OVER WEST CENTRAL AND NORTHWEST KANSAS AS A WEAK MID LEVEL DISTURBANCE
ALONG WITH THE LEFT EXIT REGION OF AN UPPER LEVEL SPEED MAX MOVES
OVER THE AREA. THE MODELS ALSO SHOW INCREASING SOUTHERLY FLOW AT THE
850 MILLIBAR LEVEL WHICH COULD ALSO HELP SUSTAIN THUNDERSTORMS THROUGH
THE NIGHT. THE BEST CHANCE FOR STORMS SHOULD BE ALONG AND/OR NORTH
OF HIGHWAY 50 AND 156. THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH
SOMEWHAT AFTER DARK BUT CAN`T RULE OUT THE POSSIBILITY OF A FEW
ELEVATED HAILERS. CHANCES FOR STORMS WILL DIMINISH LATER TONIGHT
AS THE MID/UPPER LEVEL SUPPORT MOVES EAST OF THE AREA.
ON FRIDAY, THE MAIN UPPER TROUGH MOVES OUT INTO THE CENTRAL AND
SOUTHERN PLAINS. THE MODELS DEVELOP A SURFACE LOW OVER WEST CENTRAL
KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW. BY FRIDAY
AFTERNOON THE LOW WILL BE PROGRESSING EAST WHILE A DRYLINE PUSHES
EAST ACROSS SOUTHWEST THROUGH SOUTH CENTRAL KANSAS. THE UPPER LEVEL
JET PROPAGATES EAST THROUGH THE DAY. THE 18Z MODELS ARE NOW LOOKING
LESS FAVORABLE FOR SEVERE POTENTIAL AS THE BETTER 0-6 KM SHEAR WILL
BE TO THE SOUTH AND EAST OF THE DODGE CITY CWFA DURING THE MID/LATE
AFTERNOON HOURS. WITH SOME GOOD INSTABILITY OVER THE NORTHERN AND
EASTERN SECTIONS OF THE CWA, THERE WILL STILL BE POTENTIAL FOR
SOME SEVERE STORMS AS WELL AS THE POTENTIAL FOR TORNADOES ALONG
AND NORTH OF THE FRONTAL BOUNDARY OVER CENTRAL KANSAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE
RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS
A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE
A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB
TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE
MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S
IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE
OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME
NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS
BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT
WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING
UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL
MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH
EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR
PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF
ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE
MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD
COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN
HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE
OKLAHOMA BORDER.
FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO
CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS
SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY
TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS
BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST.
GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO
WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN
KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE
SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN
BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE
MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS
ALONG THE LEE OF THE ROCKIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 110 AM CDT FRI APR 24 2015
IFR/LIFR STRATUS WILL IMPACT AREA TERMINALS EARLY FRIDAY MORNING,
WITH POTENTIAL FOR REDUCED VISIBILITY IN BR, AS SURFACE MOISTURE
TRANSPORT IS MAXIMIZED AHEAD OF A DEEPENING SURFACE LEE LOW.
SCATTERED CONVECTION BECOMES AN IMPACT IN THE EARLY TO MID
AFTERNOON. A BRIEF PERIOD OF SEVERE STORMS THE LARGE HAIL (2 TO 3
INCH DIAMETER) AND DAMAGING WIND WILL BE POSSIBLE WITH ANY ROTATING
UPDRAFTS MAINLY AFFECTING THE HAYS AND DODGE CITY TERMINALS AHEAD OF
THE SURFACE DRYLINE IN THE MORE MOIST ENVIRONMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 49 78 47 / 20 20 10 10
GCK 77 48 77 47 / 20 20 10 20
EHA 76 47 79 48 / 10 10 10 10
LBL 80 48 81 49 / 10 10 10 10
HYS 73 50 73 45 / 40 40 10 20
P28 82 52 80 50 / 20 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...BURGERT
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
111 AM CDT FRI APR 24 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 342 PM CDT THU APR 23 2015
FORECAST ISSUES IN THE SHORT TERM CENTER AROUND THUNDERSTORM CHANCES
TONIGHT AND FRIDAY AND THE SEVERE WEATHER POTENTIAL ASSOCIATED WITH
THE STORMS.
THE ATMOSPHERE OVER THE HIGH PLAINS OF EASTERN COLORADO AND FAR WESTERN
KANSAS WAS BECOMING MODERATELY UNSTABLE WITH DAYTIME HEATING THIS
AFTERNOON. A SURFACE TROUGH OF LOW PRESSURE STRENGTHENING OVER EASTERN
COLORADO WAS ALSO PROVIDING SOME LOW LEVEL CONVERGENCE AND TRIGGERING
WIDELY SCATTERED THUNDERSTORMS. SPC MESOANALYSIS SHOWS 30- 40 KNOTS
OF SHEAR IN THE 0-6 KM LAYER BUT ABOVE THIS LAYER, STRONGER SHEAR
WAS IN PLACE IN THE PRESENCE OF A STRONG SUBTROPICAL JET. THE STORMS
OVER EASTERN COLORADO WILL BE IN A FAVORABLE ENVIRONMENT TO BECOME
ROTATING SUPERCELLS. GIVEN THE STRONG EVACUATION ALOFT, LARGE HAIL
WILL BE A GOOD POSSIBILITY. THE HRRR MODEL HAS BEEN VERY CONSISTENT
WITH THUNDERSTORMS MOVING INTO WESTERN KANSAS AROUND JOHNSON AND
SYRACUSE AND POINTS NORTH THIS EVENING AROUND 23Z-01Z AND HAVE
KEPT THE BEST CHANCES IN THAT AREA EARLY THIS EVENING. AS THE
NIGHT CONTINUES, AN AREA OF THUNDERSTORMS COULD CONTINUE TO DEVELOP
OVER WEST CENTRAL AND NORTHWEST KANSAS AS A WEAK MID LEVEL DISTURBANCE
ALONG WITH THE LEFT EXIT REGION OF AN UPPER LEVEL SPEED MAX MOVES
OVER THE AREA. THE MODELS ALSO SHOW INCREASING SOUTHERLY FLOW AT THE
850 MILLIBAR LEVEL WHICH COULD ALSO HELP SUSTAIN THUNDERSTORMS THROUGH
THE NIGHT. THE BEST CHANCE FOR STORMS SHOULD BE ALONG AND/OR NORTH
OF HIGHWAY 50 AND 156. THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH
SOMEWHAT AFTER DARK BUT CAN`T RULE OUT THE POSSIBILITY OF A FEW
ELEVATED HAILERS. CHANCES FOR STORMS WILL DIMINISH LATER TONIGHT
AS THE MID/UPPER LEVEL SUPPORT MOVES EAST OF THE AREA.
ON FRIDAY, THE MAIN UPPER TROUGH MOVES OUT INTO THE CENTRAL AND
SOUTHERN PLAINS. THE MODELS DEVELOP A SURFACE LOW OVER WEST CENTRAL
KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW. BY FRIDAY
AFTERNOON THE LOW WILL BE PROGRESSING EAST WHILE A DRYLINE PUSHES
EAST ACROSS SOUTHWEST THROUGH SOUTH CENTRAL KANSAS. THE UPPER LEVEL
JET PROPAGATES EAST THROUGH THE DAY. THE 18Z MODELS ARE NOW LOOKING
LESS FAVORABLE FOR SEVERE POTENTIAL AS THE BETTER 0-6 KM SHEAR WILL
BE TO THE SOUTH AND EAST OF THE DODGE CITY CWFA DURING THE MID/LATE
AFTERNOON HOURS. WITH SOME GOOD INSTABILITY OVER THE NORTHERN AND
EASTERN SECTIONS OF THE CWA, THERE WILL STILL BE POTENTIAL FOR
SOME SEVERE STORMS AS WELL AS THE POTENTIAL FOR TORNADOES ALONG
AND NORTH OF THE FRONTAL BOUNDARY OVER CENTRAL KANSAS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 PM CDT THU APR 23 2015
THE WEAK UPPER LEVEL LOW WILL CONTINUE TO MOVE EASTWARD ACROSS
THE KS/NE BORDER FRIDAY NIGHT. THIS WILL HELP PUSH A SURFACE LOW
AND ASSOCIATED COLD FRONT THROUGH THE REMAINDER OF THE CWA AND
INTO EASTERN KANSAS. A FEW LINGERING THUNDERSTORMS WILL BE
POSSIBLE ACROSS CENTRAL KANSAS AS WELL AS AROUND THE I-70 CORRIDOR
IN THE EVENING WITH PRECIPITATION CHANCES COMING TO AN END
SOMETIME AFTER MIDNIGHT. NORTHWESTERLY WINDS WILL BE FELT BEHIND
THIS SYSTEM AND CONTINUE THROUGH THE MOST OF SATURDAY. SKIES LOOK
TO BECOME MOSTLY CLEAR BY SUNRISE SATURDAY AND CONTINUE THROUGH
THE DAY SATURDAY AS DRIER AIR MOVES INTO THE AREA. WINDS THEN
SHIFT TO MORE OF AN EASTERLY DIRECTION SATURDAY EVENING THROUGH
SUNDAY AS AN AREA OF LOW PRESSURE DEVELOPS AND INTENSIFIES
SOUTHWEST OF THE AREA. THIS OCCURS IN RESPONSE TO AN UPPER LEVEL
OPEN WAVE DIGGING INTO THE DESERT SOUTHWEST SATURDAY, INTENSIFYING
INTO AN UPPER LEVEL LOW OVER THE FOUR CORNER`S REGION SUNDAY.
MODELS THEN SUGGEST THAT THIS LOW WILL MOVE EASTWARD ACROSS THE
SOUTHERN PLAINS MONDAY INTO TUESDAY. HOWEVER, WITH THIS SYSTEM
BEING MORE THAN 4 DAYS OUT TIMING AND POSITION WILL MOST LIKELY
CHANGE OVER THE NEXT COUPLE OF MODEL RUNS. IF FUTURE MODEL RUNS
PREDICT THIS FEATURE TO MOVE FARTHER NORTH, THE CWA COULD SEE SOME
BENEFICIAL RAIN SUNDAY NIGHT THROUGH TUESDAY. NEVERTHELESS, HIGH
CLOUDS LOOK INCREASE IN COVERAGE SUNDAY AS THIS FEATURE MOVES
CLOSER TO THE AREA WITH MOSTLY CLOUDY SKIES EXPECTED SUNDAY NIGHT
THROUGH AT LEAST MONDAY. WINDS SHIFT TO MORE OF A NORTHERLY
DIRECTION BEHIND THIS SYSTEM THROUGH TUESDAY. UPPER LEVEL RIDGING
IS THEN EXPECTED TO BUILD INTO THE WESTERN UNITED STATES BEHIND
THIS SYSTEM WITH HIGH PRESSURE BEING THE DOMINATING FACTOR AT THE
SURFACE. THIS WILL BRING DRIER CONDITIONS TO WESTERN KANSAS FOR
THE REMAINDER OF THE WEEK.
AS FOR TEMPERATURES, LOWS FRIDAY NIGHT THROUGH MONDAY NIGHT WILL
GENERALLY BE IN THE 40S WITH THE EXCEPTION OF SOUTH CENTRAL KANSAS
FRIDAY NIGHT WHERE LOWER 50S WILL BE POSSIBLE AND WEST CENTRAL
KANSAS MONDAY NIGHT WHERE UPPER 30S COULD BE POSSIBLE. HIGHS LOOK
TO BE IN THE 70S WITH A FEW AREAS ACROSS THE KS/OK BORDER REACHING
INTO THE LOWER 80S SATURDAY THEN DECREASE INTO THE 60S SUNDAY. THE
COLDEST DAY OVER THE EXTENDED PERIOD LOOKS TO BE ON MONDAY WITH
HIGHS POSSIBLY ONLY REACHING TO AROUND 60 DEGREES. HIGHS ARE
FORECASTED TO REACH INTO THE MID 60S TUESDAY WITH 70S POSSIBLE
WEDNESDAY. LOWS TUESDAY THROUGH THURSDAY MORNING LOOK TO DIP INTO
THE 40S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 110 AM CDT FRI APR 24 2015
IFR/LIFR STRATUS WILL IMPACT AREA TERMINALS EARLY FRIDAY MORNING,
WITH POTENTIAL FOR REDUCED VISIBILITY IN BR, AS SURFACE MOISTURE
TRANSPORT IS MAXIMIZED AHEAD OF A DEEPENING SURFACE LEE LOW.
SCATTERED CONVECTION BECOMES AN IMPACT IN THE EARLY TO MID
AFTERNOON. A BRIEF PERIOD OF SEVERE STORMS THE LARGE HAIL (2 TO 3
INCH DIAMETER) AND DAMAGING WIND WILL BE POSSIBLE WITH ANY ROTATING
UPDRAFTS MAINLY AFFECTING THE HAYS AND DODGE CITY TERMINALS AHEAD OF
THE SURFACE DRYLINE IN THE MORE MOIST ENVIRONMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 49 78 47 / 20 20 10 10
GCK 77 48 77 47 / 20 20 10 20
EHA 76 47 79 48 / 10 10 10 10
LBL 80 48 81 49 / 10 10 10 10
HYS 73 50 73 45 / 40 40 10 20
P28 82 52 80 50 / 20 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...HOVORKA_42
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1142 PM CDT Thu Apr 23 2015
...AVIATION UPDATE...
.SHORT TERM...(This Evening through Friday)
Issued at 329 PM CDT THU APR 23 2015
A mid-level ridge was in place over the Central and Southern Plains
today with a mid-level trough progressing eastward across the
northeastern U.S. and another trough noted just north of the Baja
Peninsula. At the surface, southeasterly winds prevailed as high
pressure remained stationed just east of the forecast area. This
southeasterly flow helped to keep a low/mid cloud deck in place
across much of the region today, limiting the daytime heating.
However, visible satellite imagery showed more breaks in the cloud
cover near the Kansas/Nebraska border, resulting in afternoon
temperatures reaching into the middle 60s. Further south in
locations with more persistent cloud cover afternoon temperatures
struggled to reach near 60 degrees.
The mid-level trough north of the Baja Peninsula will lift
northeastward toward the Four Corners region overnight and progress
north of the Texas/Oklahoma panhandles Friday afternoon, which will
help to provide ample mid-level support for thunderstorm activity
late Friday afternoon through Friday evening. Ahead of this
advancing trough, water vapor imagery this afternoon showed a few
weak embedded shortwaves developing along the lee-side of the trough
over Wyoming and Colorado with increased cloud cover noted over that
region. Models show these weak waves shifting eastward with the
eastward progression of the trough, moving into Nebraska and
northern Kansas overnight into Friday morning. In general,
short-range models have trended a bit weaker with the shower and
thunderstorm potential for late tonight through the morning hours as
the region should remain capped and forcing is limited. However,
with MUCAPE values upwards of 500-1000 J/kg and 45-55kts of 0-6km
shear, cannot rule out the potential for a few strong elevated
thunderstorms to develop in which some small hail will be possible.
Short-range models show that the precipitation should be pretty
isolated this evening and become more widely scattered through the
overnight hours before diminishing in coverage from west to east
during the mid to late morning hours. As a result, models suggest
that we could see a window of a few hours from mid/late morning
through early/mid afternoon in which locations are
precipitation-free and, according to some model soundings, may
potentially see some breaks in the cloud cover, especially closer
toward central Kansas. This diminish in cloud cover will allow for
more daytime heating in the afternoon hours to boost temperatures
into the low/mid 70s from central to east central Kansas, with
cooler temperatures in the mid/upper 60s across northeast Kansas
from the lingering cloud cover. However, these high temperatures
will be very dependent upon how quickly the morning precipitation
dissipates and whether or not we are able to diminish the cloud
cover enough during the early/mid afternoon hours, so we will need
to continue to closely monitor these short-term conditions.
.LONG TERM...(Friday Night through Thursday)
Issued at 329 PM CDT THU APR 23 2015
Friday afternoon into the overnight presents a complicated weather
scenario with a likelihood of severe weather in the area, and a
potential for a few significant severe events.
The primary forecast questions through this period will be 1) How
far north does the warm sector surge? 2) How broad east/west will
the unstable warm sector be? 3) How much and how soon will the
boundary layer stabilize by mid to late evening?
In terms of the questions above, various model guidance are
generally in the same ballpark regarding how far north the warm
sector will surge, but the northern edge of the surface based
instability ranges from somewhere near the Nebraska border (GFS) to
a Council Grove to Lawrence line (NAM/NMM). The rest of guidance is
in between, and frankly the ECMWF rendition of the surface low and
warm front track looks to be quite reasonable, with the warm sector
coming as far north as Minneapolis to Manhattan to Holton line. Most
indications are also that the warm sector will not be particularly
broad east/west, and this *may* be able to limit the potential for
long track severe storms a bit as the individual storm forward speed
(40+ mph) should be faster than the system as a whole, and they
could move toward less unstable air with time. In terms of evening
stabilization, all indications point to an unstable warm sector
airmass through approximately 8-11 PM before becoming increasingly
stable. This is not entirely for sure as the surface low will track
directly across the area after midnight, but it does seem likely
that CINH will increase and the tornado threat decrease by late
evening.
The relative certainties in this forecast are following
1) Thunderstorms will develop and move across the forecast area. 2)
Wind shear parameters are very impressive and will support storm
organization. 3) The combination of steep lapse rates and strong
shear will support large hail (some very large) in storms both north
and south of the front.
The rest of the details are fuzzier but important. Damaging wind
potential does not appear to be a huge threat given low LCL heights,
but the potential for some upscale growth by mid/late evening and
very strong ambient wind fields suggest that a wind threat could
develop. The potential for tornadoes is conditional, but very
present. A worst case scenario would be if cells can remain
semi-discrete or move east of the main cluster of convection as any
isolated supercell in the warm sector would have full access to 30+
KTS of 0-1 km wind shear underneath a strong mid level steering flow
(60 KTS at 500 hPa) and exhaust jet aloft (130 KTS at 250 hPa).
There would seem to be a primary window of opportunity between 6 PM
and 10 PM for tornado potential, especially with any isolated
supercells, as the low level jet rapidly intensifies during this
period but inhibition is slow to increase. The take away message is
that the potential exists for all modes of severe weather, and while
there are complicating factors, it will be important to prepare for
a few significant severe storms.
Precipitation looks to exit the area by sunrise on Saturday. A cold
front will then move into the area from the north on Saturday
afternoon. There will be some weak instability across the area, but
most indications point to a slightly capped boundary layer with weak
forcing along the front so currently have a dry afternoon forecast.
However, if low level moisture is a bit deeper or if temperatures
ahead of the front warm up more than forecast, could possibly see a
storm or two develop.
The remainder of the forecast is rather uneventful. Have maintained
a slight chance for showers early next week as a slow moving closed
upper low drifts across the southern Plains, but for the most part
it looks like precip should remain south of the forecast area.
Temperatures look to be near or slightly below normal for much of
the long term period.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1142 PM CDT THU APR 23 2015
Forecast seems to be on track, so there are not a lot of changes
to the prev forecast. Still looks like there is a chance for
elevated showers and thunderstorms with it being tough to pin
point timing and location. Therefore continue with VCTS. There is
a little more uncertainty in how long MVFR CIGS hang in through
the day Friday. With the RAP starting to show similar solutions to
the NAM, have held onto the CIGS into the afternoon. Don`t have
much confidence in the MOS guidance indicating IFR CIGS, but it is
not out of the question. As for stronger storms, models have the
best forcing moving through between 00Z and 06Z. TS coverage may
end up being more scattered, but feel PROBs are good enough to
include a TEMPO. There will likely need to be refinements to the
forecast as the weather moves in.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1015 PM MDT THU APR 23 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 112 PM MDT THU APR 23 2015
LOW CLOUDS THAT WERE PRESENT ACROSS THE AREA DURING THE MORNING
HOURS CONTINUED TO LINGER FOR SOME LOCATIONS ACROSS THE TRI STATE
AREA IN THE EARLY AFTERNOON ON VISIBLE SATELLITE IMAGERY...HOWEVER
MOST LOCATIONS WERE UNDER PARTLY TO MOSTLY CLEAR SKIES. RAP 500 MB
ANALYSIS AND WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH ACROSS
THE CENTRAL HIGH PLAINS REGION...HOWEVER A LONGWAVE TROUGH ACROSS
THE GREAT BASIN REGION WAS MOVING EASTWARD INTO THE CENTRAL HIGH
PLAINS.
THE ADVANCING TROUGH WILL BRING SOME POCKETS OF HIGHER POTENTIAL
VORTICITY VALUES ACROSS THE TRI STATE AREA LATER THIS AFTERNOON AND
TONIGHT...WHICH WILL HELP DESTABILIZE THE ATMOSPHERE AND CAUSE
STORMS TO DEVELOP. A SURFACE STATIONARY BOUNDARY TO THE WEST ALONG
THE COLORADO FRONT RANGE WILL ALSO PROVIDE THE NEEDED PUSH AT THE
SURFACE TO GET STORMS GOING. MOST MODEL GUIDANCE HAS INITIATION
OCCURRING SOMETIME BETWEEN 21 AND 00Z IN EASTERN COLORADO WITH
STORMS GETTING GOING BY 00Z. PROFILE CAPE BETWEEN 1000 AND 1500
J/KG AND BULK SHEAR BETWEEN 30 AND 35 KTS MAY BE ENOUGH TO CAUSE
SOME STORMS TO PRODUCE LARGE HAIL...AND DRY MID LEVELS IN MODEL
SOUNDINGS WITH DCAPE BETWEEN 800 AND 1000 J/KG COULD RESULT IN
DAMAGING WINDS GUSTS. THE SHEAR VALUES DIMINISH OVERNIGHT...BUT
CAPE WILL STILL BE PRESENT OVERNIGHT AS STORMS MOVE EASTWARD.
THEREFORE...EXPECTING STORMS TO CONTINUE OVERNIGHT FOR SOME
LOCATIONS.
THE SURFACE STATIONARY FRONTAL BOUNDARY WILL REMAIN DRAPED ACROSS
THE TRI STATE AREA OVERNIGHT...WHICH WILL BRING SOUTHEAST WINDS AT
THE SURFACE AND INCREASED RELATIVE HUMIDITIES OVERNIGHT. AS A
RESULT...FOG WILL DEVELOP AND CLOUD COVER WILL REMAIN INCREASED
OVERNIGHT. EXPECTING LOW TEMPERATURES TO BE SLIGHTLY WARMER AS A
RESULT OF THE BLANKETING CLOUD COVER IN THE UPPER 40S.
FOG AND LOWER CLOUDS WILL BEGIN TO DIMINISH TOWARD THE EARLY TO MID
MORNING HOURS...BUT CLOUDS WILL RETURN DURING THE EARLY AFTERNOON AS
A SURFACE WARM FRONT APPROACHES THE TRI STATE AREA. RAIN SHOWERS
AND THUNDERSTORMS WILL DEVELOP IN THE LATE MORNING TO EARLY
AFTERNOON HOURS...MAINLY EAST OF HIGHWAY 83. CAPE VALUES AROUND
1000 J/KG AND BULK SHEAR BETWEEN 35 AND 40 KTS WILL BRING SOME
SEVERE POTENTIAL WITH LARGE HAIL AND DAMAGING WINDS...ALTHOUGH THE
MAIN ATMOSPHERIC DYNAMICS ARE WELL EAST OF OUR FORECAST AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 241 PM MDT THU APR 23 2015
THE UPPER TROUGH AND SURFACE LOW MOVING ACROSS THE AREA ON FRIDAY
WILL CONTINUE TO LIFT ENE AS A CLOSED LOW FRIDAY NIGHT WITH WEAK
SHORT WAVE RIDGING ALOFT OVER THE CENTRAL HIGH PLAINS ON SATURDAY.
SATURDAY LOOKS MOSTLY DRY BETWEEN SYSTEMS WITH THE NEXT LOW
PRESSURE CENTER DIVING INTO THE SOUTHWEST U.S. SOUTH OF THE
4-CORNERS REGION DURING BY SUNDAY MORNING. THE LOW ALOFT MOVES
INTO THE WEST TEXAS PANHANDLE REGION BY MONDAY MORNING...MOVING
SLOWLY INTO POSITION OVER EAST TEXAS AND EAST OKLAHOMA BY TUESDAY
MORNING AS THE SURFACE LOW TRACKS FURTHER SOUTH ALONG THE GULF
COAST OF TEXAS.
WITH THE MAIN LOW PRESSURE AREA ACROSS THE SOUTH CENTRAL U.S. WELL
SOUTH OF THE FORECAST AREA...THE SATURDAY NIGHT THROUGH MONDAY
NIGHT TIME FRAME WILL REMAIN UNSETTLED ACROSS THE FORECAST AREA WITH
A CHANCE OF RAIN SHOWERS AND THUNDERSTORMS...BUT EXPECT THE BULK
OF THE PRECIPITATION TO STAY OVER THE SOUTHERN PLAINS. TUESDAY
THROUGH THURSDAY SHOULD BE DRY AS THE AMPLIFYING RIDGE OVER THE
WEST COAST MOVES OVER THE ROCKIES AND HIGH PLAINS REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1015 PM MDT THU APR 23 2015
KGLD...STRATUS AND MVFR CIGS EXPECTED AT TAF ISSUANCE OR VERY
SHORTLY AFTER WITH CONFIDENCE INCREASING IN THE 07Z-15Z TIMEFRAME
FOR WIDESPREAD IFR/VLIFR CONDITIONS TO OCCUR. CONDITIONS EXPECTED
TO IMPROVE TO VFR CATEGORY AROUND 18Z-19Z. A WEATHER DISTURBANCE
APPROACHES THE TERMINAL AROUND 21Z MOVING THROUGH AND OUT OF THE
IMMEDIATE AREA AROUND 00Z WITH ONLY SOME MID AND HIGH CLOUDS
LEFTOVER. HAVE MENTIONED VCTS IN THE 21Z-00Z TIMEFRAME BUT SOME OF
THE MODELS SUGGESTING A LITTLE LATER STARTING AND ENDING TIME SO
ADJUSTMENTS WILL LIKELY OCCUR. WINDS THROUGH THE PERIOD GENERALLY
12KTS OR LESS...EXCEPT IN THE VICINITY OF ANY THUNDERSTORMS.
KMCK...MVFR CIGS EXPECTED AT TAF ISSUANCE OR VERY SHORTLY AFTER
WITH CONFIDENCE INCREASING IN THE 08Z-15Z TIMEFRAME FOR
WIDESPREAD IFR/VLIFR CONDITIONS TO OCCUR. FOR 16Z-19Z MVFR
CONDITIONS EXPECTED THEN VFR BY 20Z. A WEATHER DISTURBANCE
APPROACHES THE TERMINAL AROUND 22Z MOVING THROUGH AND OUT OF THE
IMMEDIATE AREA AROUND 01Z WITH ONLY SOME MID CLOUDS LEFTOVER. HAVE
MENTIONED VCTS IN THE 22Z-01Z TIMEFRAME BUT SOME OF THE MODELS
SUGGESTING A LITTLE LATER STARTING AND ENDING TIME SO ADJUSTMENTS
WILL LIKELY OCCUR. WINDS THROUGH THE PERIOD GENERALLY UNDER
12KTS...EXCEPT IN THE VICINITY OF ANY THUNDERSTORMS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...MK
LONG TERM...LOCKHART
AVIATION...99
AREA FORECAST DISCUSSION
NWS PADUCAH KY
300 AM CDT FRI APR 24 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
SEVERAL CHALLENGES TO THE FORECAST FOR THIS PART OF THE PACKAGE.
MID-HIGH LEVEL CLOUDS STREAMING ACROSS THE AREA EARLY THIS MORNING
AND SATELLITE SUGGESTS PATCHY MID-HIGH LEVEL CLOUDS WILL CONTINUE
THROUGH MOST OF THE DAY. SEVERAL SMALL PIECES OF ENERGY HEADED OUR
WAY TODAY. HRRR MODEL PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN SECTIONS LATER THIS MORNING AND THESE ARE SLOWLY
EXPECTED TO SPREAD EAST LATE THIS AFTERNOON.
BY TONIGHT A WARM FRONT WILL DEVELOP TO OUR SOUTH. CURRENT WATER
VAPOR IMAGES DEPICT MOISTURE STREAMING NORTHEAST OUT OF OLD MEXICO
AND TEXAS. SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE WIDESPREAD
TONIGHT ACROSS THE AREA.
ON SATURDAY...THERE SHOULD BE A LULL IN THE ACTION DURING THE
MORNING HOURS AS THE MAIN PRECIP ENDS FROM SOUTHWEST TO NORTHEAST.
THE CLOUDS ARE EXPECTED TO BREAK UP FOR SEVERAL HOURS DURING THE
MORNING HOURS ESPECIALLY OVER THE CENTRAL AND SOUTHERN SECTIONS.
AS THIS HAPPENS, MOST OF THE AREA WILL BECOME VERY UNSTABLE AS
WIND FIELDS BECOME MORE FAVORABLE FOR SEVERE WEATHER DURING THE
AFTERNOON HOURS. SPC HAS A MAJORITY OF THE AREA IN AN ENHANCED
RISK AND THIS SEEMS PRUDENT AS CONFIDENCE LEVELS CONTINUE TO
INCREASE FOR SEVERE WEATHER. VERY FAVORABLE LAPSE RATES SHOULD
ALLOW DEEP CONVECTION TO BEGIN BY EARLY-MID AFTERNOON. 0-3 KM
BULK SHEAR VECTORS WILL RANGE FROM 35 TO 40 KTS AS LOW LEVEL WINDS
INCREASE...ESPECIALLY OVER WEST KENTUCKY.
THERE IS POTENTIAL FOR LARGE HAIL...DAMAGING WINDS...AND A FEW
TORNADOES TOMORROW AFTERNOON AND EARLY EVENING ESPECIALLY OVER
WESTERN KENTUCKY.
PRECIPITATION SHOULD END SATURDAY NIGHT WITH SOME SUNSHINE ON
SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
SLIGHTLY BETTER FORECAST CONFIDENCE IN THE LONG TERM.
VIRTUALLY ALL OF THE WEATHER...OR LACK THEREOF...IN THE LONG TERM
PERIOD HINGES ON THE DEVELOPMENT AND EVOLUTION OF A STORM SYSTEM
FORECAST TO MOVE OUT OF THE SOUTHERN PLAINS.
THE GFS CONTINUES TO TRACK THIS SYSTEM EAST NORTHEASTWARD BRINGING
IT AND ITS ASSOCIATED PRECIPITATION SLIGHTLY FARTHER NORTH THEREBY
AFFECTING THE SOUTHERN HALF OF OUR CWA TUESDAY AND TUESDAY NIGHT. IN
THE SAME TIME FRAME THE ECMWF AND CANADIAN CONTINUE TO TRACK THE
SYSTEM MORE EASTERLY KEEPING ALL PRECIPITATION SOUTH OF OUR CWA. ON
A SIDE NOTE...THE LATEST GFS SOLUTION IS SLIGHTLY FARTHER SOUTH THAN
IT WAS FORECASTING 24 HOURS AGO. IF THIS TREND CONTINUES WE MAY BE
ABLE TO EVENTUALLY REMOVE CURRENT POPS.
FOR WHATEVER REASON THE SUPERBLEND STILL LEANS MORE TOWARD THE GFS
SOLUTION SO BASICALLY TOOK THE SUPERBLEND POPS AND TONED THEM DOWN A
BIT.
HIGH PRESSURE AT THE SURFACE SHOULD KEEP THE REGION DRY WITH THE
EXCEPTION OF TUESDAY AND TUESDAY NIGHT. TEMPERATURES THROUGH MOST OF
THE PERIOD WILL REMAIN BELOW NORMAL BUT RIDGING ALOFT SHOULD WARM
READINGS BACK TO NEAR NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION...
ISSUED AT 1139 PM CDT THU APR 23 2015
MID-LEVEL MOISTURE WILL OVERSPREAD THE AREA THROUGH THE
MORNING...AND CEILINGS MAY DESCEND TO NEAR MVFR LEVELS IN THE
EVENING. A FEW SHOWERS WILL BE POSSIBLE IN THE EVENING...BUT THEY
SHOULD HAVE LITTLE IMPACT ON THE TERMINALS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...PS
LONG TERM...JP
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1156 PM CDT THU APR 23 2015
.SYNOPSIS...
ISSUED AT 320 PM CDT THU APR 23 2015
SPLIT UPPER LEVEL PATTERN OVER THE WESTERN HALF OF THE CONUS...BROAD
CYCLONIC FLOW TO THE EAST. A SHORTWAVE RIDGE WAS TRANSLATING EAST
ACROSS THE CENTRAL PLAINS...IN ADVANCE OF A STRONG PV MAX SLOWLY
MOVING NORTHEASTWARD ACROSS THE DESERT SOUTHWEST. THE ASSOCIATED
HEIGHT FALLS WITH THIS PATTERN WERE SUPPORTING THE GRADUAL DEEPENING
OF A LEE SIDE SFC TROUGH FROM NORTHEAST COLORADO THROUGH THE WESTERN
NEBRASKA PANHANDLE. EAST OF THIS TROUGH WINDS WERE BREEZY OUT OF THE
SOUTH...TRANSPORTING LOW LEVEL MOISTURE INTO THE CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 320 PM CDT THU APR 23 2015
CUMULUS CLOUDS AND A FEW SHOWERS AND THUNDERSTORMS HAVE ALREADY
DEVELOPED JUST WEST OF THE CWA EARLY THIS AFTERNOON. HI-RES MODELS
HAVE CONSISTENTLY SHOWN THE THUNDERSTORM ACTIVITY INCREASING IN
COVERAGE AND MOVING EAST LATER THIS AFTERNOON AS A WEAK UPPER LEVEL
SHORTWAVE EJECTS OUT OF THE CENTRAL ROCKIES. THE BEST CHANCES
THROUGH THE EVENING WILL GENERALLY BE CONFINED TO THE PANHANDLE AND
SOUTHWEST NEBRASKA. AS FAR AS STORM INTENSITY...MLCAPE IN THE
VICINITY OF THE SFC TROUGH WILL NEAR 1000 J/KG BY LATER AFTERNOON
AND EARLY EVENING. STEEP MID LEVEL LAPSE RATES OF 7-8 C/KM ARE ALSO
IN PLACE OVER THE HIGH PLAINS. A STORM OR TWO REACHING STRONG TO
SEVERE LIMITS WITH HAIL AND GUSTY WINDS CANNOT BE RULED OUT...MAINLY
WEST OF HWY 61. THE ABILITY FOR STORMS TO SUSTAIN THEMSELVES AND
REMAIN ORGANIZED IS IN QUESTION DUE RATHER WEAK MID LEVEL FLOW AND
DEEP LAYER SHEAR ONLY AROUND 25 TO 30 KTS. THE MORE FAVORABLE
ENVIRONMENT WILL REMAIN TO THE SOUTH WHERE FASTER FLOW ALOFT AND
BETTER SHEAR PROFILES RESIDE.
THUNDERSTORM CHANCES MOVE EAST OVERNIGHT BUT COVERAGE SHOULD REMAIN
SCATTERED. UPPER LEVEL LOW CURRENTLY OVER THE DESERT SOUTHWEST WILL
EJECT EASTWARD TOWARD THE CENTRAL PLAINS. THIS WILL KEEP SOUTHERLY
FLOW IN PLACE OVERNIGHT...AND EVENTUALLY THE REDEVELOPMENT OF
STRATUS CLOUDS OVER MUCH OF THE AREA. PATCHY FOG IS POSSIBLE OVER
CENTRAL NEB...BUT BUFKIT DATA CONTINUES TO SUPPORT THICK LOW STRATUS
IN OUR ZONES. THIS IS ALSO SUPPORTED BY VISBY FIELDS IN RECENT RUNS
OF THE HRRR AND NAM. CONFIDENCE NOT HIGH ENOUGH TO INCLUDE ANY FOG
IN THE GRIDS AT THIS POINT...BUT THE EVENING SHIFT WILL NEED TO
REEVALUATE.
MODELS PAINT QPF ACROSS MUCH OF THE CWA BY FRIDAY AFTERNOON...BUT
REMAIN ALL OVER THE PLACE IN REGARDS TO THEIR PLACEMENT. EXPECTING
SCATTERED AND DISORGANIZED SHOWERS AND THUNDERSTORMS DUE TO LACK OF
A FOCUS FOR DEVELOPMENT. NOT EXPECTING MUCH IN THE WAY OF SEVERE
WEATHER AS THE MUCH BETTER ENVIRONMENT WILL BE OFF TO OUR SOUTH AND
EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU APR 23 2015
LONG WAVE TROUGH WILL BE MOVING INLAND FROM THE WEST COAST
FRIDAY NIGHT...WITH A LEAD SHORTWAVE MOVING ACROSS THE CENTRAL PLAINS
AHEAD OF THE TROUGH FRIDAY NIGHT. OPERATIONAL MODELS FCST THE
CENTRAL PLAINS TROUGH TO BECOME CLOSED NEAR OR JUST WEST OF THE MID
MISSOURI VALLEY. THIS WILL BE A RATHER DISORGANIZED EVENT...AND
WITH ONLY WEAK MOISTURE TRANSPORT...LIFT WILL ALSO BE SOMEWHAT
LIMITED AND UNFOCUSED. THIS CONTINUES TO SUGGEST A SHOWERY AND
UNORGANIZED PRECIPITATION EVENT. WILL LIMIT HIGHEST POPS TO 40 TO
50 PERCENT EVENING AND 20 TO 30 PERCENT AFTER MIDNIGHT. BEST
INSTABILITY ACROSS SERN ZONES...WITH HIGHER TSTM CHANCES WITH ONLY
ISOLATED EXPECTED ACROSS THE NORTH/NORTHWEST.
THE MAIN UPPER TROUGH WILL DIG SOUTHEAST ACROSS THE GREAT BASIN ON
SATURDAY AS A TRANSITORY RIDGE MOVES INTO THE CNTRL PLAINS. THIS
WILL LESSEN POPS TO ONLY A SLIGHT CHANCE NORTH AND WEST WITH PARTLY
SUNNY SKIES AND HIGH TEMPS NEAR 60 NORTHEAST TO NEAR 70 FAR
SOUTHWEST. THE GFS ENSEMBLE...GFS...AND ECMWF ALL AGREE THAT THE
UPPER TROUGH WILL DEEPEN INTO THE FOUR CORNERS REGION SATURDAY
NIGHT WITH AN AMPLIFIED SRLY FLOW ALOFT ACROSS THE CNTRL HIGH
PLAINS. CHCS FOR SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE
HIGHS PLAINS WITH CHC POPS WEST OF HWY 83...AND NO WX ACROSS THE
EAST. ANY SHOWERS THAT DEVELOP WILL MOVE NORTH WILL LITTLE OR NOW
EASTWARD PROGRESSION. MEDIUM RANGE MODELS THEN INDICATED CLOSED
LOW WILL TRACK EAST ACROSS NEW MEXICO...THE TEXAS PANHANDLE...AND
THEN ACROSS NORTHERN TEXAS AND SOUTHERN OKLAHOMA SUNDAY THROUGH
MONDAY NIGHT. THERE REMAINS ENOUGH MODEL AGREEMENT AND CONFIDENCE
TO KEEP POPS INTO THE LIKELY CATEGORY ACROSS THE EASTERN PANHANDLE
SUNDAY WITH CHC POPS EAST TO VALENTINE THROUGH BROKEN BOW. AS NRN
STREAM TROUGH APPROACHES SUNDAY NIGHT AND MONDAY...POPS LESSEN AND
REMAIN ONLY ACROSS THE WEST. DRY MONDAY NIGHT AND BEYOND. UPPER
RIDGE OVER THE GREAT BASIN WILL SLOWLY BUILD EAST INTO THE CENTRAL
CONUS THROUGH THURSDAY. THE COOLEST DAY LOOK TO BE SUNDAY AS
EASTERLY UPSLOPE WINDS AND CLOUDINESS/SHOWERS LIMITS HIGHS TO
LOWER MID 50S WEST TO NEAR 60 EAST. HIGHS THEN WARM INTO THE 60S
MONDAY/TUESDAY...LOW 70S WEDNESDAY...THEN MID/UPPER 70S THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1154 PM CDT THU APR 23 2015
LOOK FOR LOW LEVEL CLOUDINESS TO DEVELOP OVERNIGHT AT BOTH THE
KLBF AND KVTN TERMINALS. CIGS WILL RANGE FROM 700 TO 1500 FT AGL.
LOOK FOR CIGS TO LIFT TO VFR FRIDAY AFTERNOON WITH CIGS RANGING
FROM 10000 TO 20000 FT AGL. FOR FRIDAY EVENING...THERE WILL BE A
THREAT FOR THUNDERSTORMS. GIVEN THE EXPECTED WIDELY SCATTERED
COVERAGE...WILL HANDLE THIS WITH A PROB30 GROUP.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MARTIN
SHORT TERM...MARTIN
LONG TERM...ROBERG
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
129 AM EDT FRI APR 24 2015
.SYNOPSIS...
A LARGE STORM SYSTEM WILL SLIDE NORTHEASTWARD OVERNIGHT THROUGH
FRIDAY, KEEPING TEMPERATURES WELL BELOW NORMAL. SNOW SHOWER AND
FLURRY ACTIVITY WILL DIMINISH AS DRIER AIR MOVES IN LATE TONIGHT
AND FRIDAY, WITH IMPROVING CONDITIONS FOR SATURDAY WITH SUNSHINE
EXPECTED.
&&
.NEAR TERM /THROUGH TODAY/...
WATER VAPOR IMAGERY SHOWS A LARGE UPPER LEVEL CYCLONE OVER
NORTHERN NEW ENGLAND AND SOUTHERN QUEBEC THIS EVENING WHICH
CONTINUES TO LEAD TO A COLD AND MOIST NORTHWEST FLOW OF AIR ACROSS
CENTRAL NY AND NORTHEAST PA. 850 MB TEMPERATURES WERE VERY CHILLY
FOR THIS TIME OF YEAR RUNNING AROUND -8C TO -10C AT THIS TIME.
HRRR, RAP. WRF NMM, WRF ARW AND NAM12 ALL SHOW 850 MB TEMPS
DROPPING TO -11C OR SO BY 12Z. LAKE ONTARIO AND ERIE WATER
TEMPERATURES WERE ARND +1 TO 3C LEADING TO SOME LAKE ENHANCEMENT
OF THE SYNOPTIC SCALE MOISTURE THAT WAS WRAPPING ARND THE UPPER
LEVEL LOW. THIS WILL CONTINUE TO LEAD TO LATE SEASON SNOW SHOWERS
AND FLURRIES OVERNIGHT.
ONE SHORT WAVE WAS PASSING EAST OF OUR REGION AT THIS TIME SO THE
RADAR COVERAGE OF THE SNOW SHOWERS AND FLURRIES HAS DIMINISHED AT
THIS TIME. THE RAP SHOWS ANOTHER SHRT WAVE WILL PASS BY ARND 5-6Z
WHICH SHUD RAMP SN SHOWER ACVTY UP A BIT...ESPECIALLY IN NC NY
WHERE THERE WILL BE MORE LAKE MOISTURE ON A W-NW LL FLOW PATTERN.
THE REST OF THE FORECAST AREA WILL REMAIN UNDER A STRATOCUMULUS
DECK THROUGH THE NIGHT WITH A FEW FLURRIES AT TIMES.
FOR FRIDAY...THE STRG LATE APRIL SUN WILL EVENTUALLY BREAK UP THE
LAKE ENHANCED MOISTURE AND CLOUDS AND WE SHUD SEE SOME BREAKS BY
AFTERNOON. OUR WRN AND SRN PARTS OF OUR FORECAST AREA LIKELY WILL
BREAK OUT AND BECOME PC TO MS BY AFTERNOON. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH SUB FREEZING TEMPERATURE MOST AREAS
OVERNIGHT. THERE IS TOO MUCH WIND AND CLOUDS FOR ANY FROST AND
OUR GROWING SEASON HAS NOT BEGUN YET SO NO MENTION OF FROST IN OUR
ZONES FOR OVERNIGHT.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
STACKED CYCLONE DRIFTS FROM MAINE TO OFF THE ATLANTIC COAST THIS
PERIOD. AFTER WIDELY SCATTERED RAIN/SNOW SHOWER ACTIVITY DURING
THE MORNING HOURS, ESPECIALLY OVER NERN FA, DRY NORTHWESTERLY
FLOW SHOULD YIELD FAIR WEATHER FOR FRIDAY AFTERNOON AND SATURDAY.
AFTER MAXES IN THE UPPER 30S TO MIDDLE 40S ON FRIDAY, BL-850MB
TEMPS WILL REBOUND SEVERAL DEGREES CELSIUS FOR SATURDAY. GIVEN DRY
ATMOSPHERE AND GOOD AMOUNT OF SUN, THINK MAX TEMPS WILL BOUNCE
BACK INTO THE LOWER 50S IN MOST SPOTS, THOUGH THIS WILL STILL BE
8 TO 12 DEGREES BELOW NORMAL MAX TEMPS.
A SURFACE LOW PRESSURE CENTER WILL SLIDE EASTWARD THROUGH VA/NC ON
SUNDAY, WHILE A COOL RIDGE BUILDS SOUTH THROUGH THE GREAT LAKES
INTO THE OHIO VALLEY. BELIEVE THE PRECIPITATION WILL REMAIN SOUTH
AND WEST OF OUR FA, THOUGH A WEAK WAVE IN THE UPPER FLOW MAY
SPAWN A SPRINKLE OR LIGHT SHOWER UP THE LAKE PLAIN.
330 AM EDT UPDATE...
THE STACKED UPPR LOW WILL MOVE AS FAR EAST AS MAINE AND WE WILL
REMAIN UNDER A NW FLOW ALOFT ON FRIDAY. THE CHANCE FOR SHOWERS
WILL CONTINUE THRU FRIDAY AS WE WILL REMAIN WITHIN THE WRAP AROUND
MOISTURE. THE CHANCE FOR SHOWERS ON SAT WILL BECOME LESS AS THE
MOISTURE WITH THIS SYSTEM SHIFT SLIGHTLY FURTHER EAST AND THE LOW
SHIFTS SLIGHTLY FURTHER EAST OFF THE EAST COAST. PRECIP TYPE WILL
BE DEPENDENT ON SFC TEMPS... THUS SNOW POSSIBLE DURING THE
OVERNIGHT HOURS AND RAIN DURING THE DAY TIME.
NW FLOW ALOFT WILL REMAIN OVER THE REGION THRU THE FORECAST PERIOD
AND CONTINUE TO SUPPORT COLDER THAN NORMAL TEMPS ACROSS THE
REGION. TEMPS ON SAT WILL SLIGHTLY REBOUND INTO THE LOW TO UPPR
40S. AS THE UPPR LOW SHIFT EAST ON SAT... TEMPS WILL BE ABLE TO
RISE INTO THE LOWER 50S OVER MUCH OF THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
BOTH THE GFS AND EURO SHOW A DEEP AND VERTICALLY STACKED LOW
WOBBLING OFF THE NE CST ON MON. NLY FLOW BHD THE FLOW WITH THE LWR
UPR HGTS WILL KEEP ISLTD TO SCT SHOWRS OVER THE FCST AREA...ESP
OVER THE NY ZONES...WITH BLO NRML DAYTIME TEMPS.
IRONICALLY...THE EURO IS MORE PROGRESSIVE WITH THE SYSTEM AND
SHOWS SOME IMPRVMT LTR TUE INTO THU WITH WEAK SFC RDGG AND A
NARROW RDG ALOFT. GFS WANTS TO KEEP THE UPR LOW HANGING ARND AND
IN FACT CAPTURES A SRN STREAM SYSTEM LATE IN THE PD TO ENHANCE
THE UPR TROF.
MODELS HAVE BEEN INCONSISTENT WITH THE FCST IN THE LONG TERM LDG
TO A LOW CONFIDENCE FCST...NOT ALL THAT UNUSUAL THIS TIME OF YEAR.
SO...CONTD WITH THE HPC GUID IDEA OF LOW CHANCE OR SLGT CHANCE
POPS FOR MUCH OF THE LONG TERM...ESP IN THE NRN AND ERN ZONES.
WITH THE NLY FLOW...TEMPS WILL REMAIN BLO NRML...ESP DURING THE
DAY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
06Z FRI UPDATE... MAINLY UNRESTRICTED/VFR CONDS WILL BE WITH US
FOR THE VALID TAF PD (THROUGH 06Z SAT). THE EXCEPTION COULD BE
AROUND DAYBREAK (EITHER SIDE OF 12Z)...WHEN SCTD SNOW SHWRS/LWR
CIG BASES COULD PROVIDE MVFR/FUEL ALT CONDS...WITH A LOWER
PROBABILITY OF BRIEF IFR RESTRICTIONS AT KSYR/KITH/KBGM.
NW SFC WINDS AROUND 10 KT EARLY THIS MRNG...WILL INCREASE AND
BECOME GUSTY DURING THE LATE MRNG-AFTN HRS...BEFORE DIMINISHING
AGN THIS EVE (AFTER 00Z SAT).
.OUTLOOK...
SAT-SUN...VFR.
MON-TUE...OCNL -SHRA...WITH BRIEF MVFR RESTRICTIONS...MAINLY NY
TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/DJP
NEAR TERM...DJN
SHORT TERM...DJP
LONG TERM...DGM
AVIATION...DJN/MLJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1145 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 1145 PM CDT THU APR 23 2015
QUICK UPDATE TO INCLUDE THUNDERSTORMS IN THE FORECAST.
THERE IS SOME MID-LEVEL INSTABILITY THIS EVENING PER THE 00 UTC
BISMARCK SOUNDING. A LOW LEVEL JET HAS KICKED IN PROVIDED ENOUGH
LIFT FOR CONVECTION TO OCCUR AND SPARK A FEW ISOLATED
THUNDERSTORMS.
REST OF THE FORECAST IS ON TRACK WITH SHOWERS/THUNDERSTORMS
CONTINUING ACROSS THE JAMES VALLEY THROUGH THIS MORNING.
UPDATE ISSUED AT 938 PM CDT THU APR 23 2015
TRENDED THE POPS EAST WITH THE RADAR RETURNS. HRRR MODEL CONTINUES
TO DEVELOP SHOWERS OVER THE JAMES RIVER VALLEY IN LOW LEVEL WARM
ADVECTION THROUGH TONIGHT. CLEARING WEST.
UPDATE ISSUED AT 724 PM CDT THU APR 23 2015
UPDATE FOR POPS AND CLOUDS MAINLY. SURFACE LOW PRESSURE IDENTIFIED
BY RUC MODEL CENTERED NEAR THE BLACK HILLS WITH A SOUTHEAST TO
EASTERLY WIND COMPONENT ACROSS ALL OF NORTH DAKOTA. THIS WILL
MAINTAIN FAVORABLE SHEAR AND MAY SUPPORT MAINTAINING THE LIMITED
MOISTURE ACROSS THE JAMES RIVER VALLEY TONIGHT. SHOWERS EXPECTED TO
DEVELOP AND REMAIN IN THE JAMES RIVER VALLEY TONIGHT.
UPDATE ISSUED AT 503 PM CDT THU APR 23 2015
GETTING REPORTS OF SNOW FROM STANLEY AND PARSHALL AREAS. LOOKS
LIKE COOLING TO THE WET BULB IS CREATING ENOUGH COOLING FOR SNOW
LATE THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
SHOWERS THIS AFTERNOON THROUGH TONIGHT HIGHLIGHT THE SHORT TERM
FORECAST.
OUTSIDE OF THE HIGHWAY 200 CORRIDOR...THE MAJORITY OF
PRECIPITATION IS NOT REACHING THE GROUND DUE TO DRY AIR IN THE
SUB-800 MB LAYER. THE 16-18 UTC HRRR ITERATIONS HAVE THE BEST
HANDLING OF THE ONGOING PRECIPITATION...ESPECIALLY THAT WHICH IS
REACHING THE GROUND...AND WILL WEIGH HEAVILY ON THEIR SOLUTIONS
THROUGH AFTERNOON AND EVENING. THEREAFTER...THE 12 AND INCOMING 18
UTC GLOBAL AND HIGH RESOLUTION SUITES ARE IN AGREEMENT ON ELEVATED
SHOWERS DEVELOPING TONIGHT ACROSS THE JAMES AND INTO THE RED RIVER
VALLEYS BY 05 UTC WITH A MODEST LOW LEVEL JET AHEAD OF THE
SURFACE LOW ACROSS WESTERN SOUTH DAKOTA. GIVEN MARGINALLY POSITIVE
SHOWALTER VALUES...WILL NOT PUT IN THUNDER AT THIS TIME. FRIDAY
APPEARS TO BE DRY ACROSS WESTERN AND CENTRAL NORTH DAKOTA BETWEEN
THE STRONGER LOW ACROSS THE CENTRAL PLAINS AND THE PACIFIC
NORTHWEST TROUGH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 303 PM CDT THU APR 23 2015
A SPLIT FLOW THROUGH THE WEEKEND WITH PERIODS OF INTERACTION
BETWEEN THE SOUTHERN STREAM AND NORTHERN STREAM. THIS WILL
ULTIMATELY SET UP AN INCREASINGLY WET/UNSETTLED WEATHER PATTERN
THROUGH EARLY NEXT WEEK. TWO MAIN SHORTWAVES TO PUSH ACROSS WESTERN
AND CENTRAL NORTH DAKOTA FRIDAY NIGHT THROUGH MONDAY. THE LATEST
ECMWF IS ADVERTISING A MORE CONTINUOUS RAIN OVER THE WEEKEND INTO
MONDAY...WHILE THE GFS/CANADIAN GEM HAS A MORE DISTINCT START/END
TIME WITH EACH WAVE. UTILIZED A BLEND OF THE ABOVE MODELS ABOVE.
EXPECT A BRIEF DRYING AND WARMING TREND BY MIDWEEK...THEN A
PROGRESSIVE AND POSSIBLY UNSETTLED WEATHER PATTERN SETTING UP LATE
IN THE EXTENDED.
FOR FRIDAY NIGHT THROUGH SATURDAY...A TRANSITORY 700MB-500MB RIDGE
DEVELOPS OUT AHEAD OF AN APPROACHING SHORTWAVE TROUGH SLIDING INTO
THE NORTHERN ROCKIES. THIS SHOULD KEEP CONDITIONS DRY FOR MOST AREAS
FRIDAY NIGHT BEFORE EAST TO SOUTHEAST WINDS ADVECT AN AREA OF
MOISTURE INTO THE WEST. THIS MOISTURE WILL CONVERGE INTO AN
APPROACHING SURFACE COLD FRONT IN EASTERN MONTANA. THUS POPS BECOME
LIKELY THEN CATEGORICAL SATURDAY IN THE WEST...WITH DRIER CONDITIONS
IN THE EAST AS MID LEVEL RIDGING REMAINS INTACT UNTIL 00Z SUNDAY.
SATURDAY NIGHT THROUGH MONDAY NIGHT...AS MENTIONED ABOVE THERE ARE
DIFFERENCES IN THE ECMWF AND GFS/GEM...ESPECIALLY SATURDAY NIGHT
THROUGH SUNDAY. PER GFS/GEM...THE SURFACE LOW/COLD FRONT AND SHORTWAVE
MOVE INTO SOUTHERN CANADA WITH SHOWERS DIMINISHING SATURDAY NIGHT
INTO SUNDAY. THE TRAILING COLD FRONT STALLS UNDER A SOUTHWEST FLOW
ALOFT...WITH LOW LEVEL SOUTH TO SOUTHEAST WINDS FEEDING MOISTURE
INTO NORTH DAKOTA. THE GFS/GEM MODELS TREND TOWARD A CESSATION TO
THE PRECIPITATION UNTIL SUNDAY NIGHT WHEN THE THE FRONT BECOMES
RE-ENERGIZED AS THE NEXT SHORTWAVE TROUGH APPROACHES. WITH THE
SURFACE COLD FRONT AND SOUTHERN STREAM MOISTURE ALREADY IN
PLACE...THIS SETS THE STAGE FOR A MORE WIDESPREAD PRECIPITATION
EVENT SUNDAY NIGHT THROUGH MONDAY. AS MENTIONED ABOVE THE LATEST
ECMWF REALLY DOES NOT STOP THE PRECIPITATION WITH THE INITIAL
SHORTWAVE...RATHER KEEPS THE SURGE MAINLY CONTINUOUS IN THE WEST AND
SLOWLY SPREADS IT EAST AND NORTH THROUGH MONDAY. TOTAL PRECIPITATION
AMOUNTS COULD RANGE BETWEEN A HALF INCH TO ONE INCH IN THE WEST TO
AROUND A QUARTER OF AN INCH IN CENTRAL NORTH DAKOTA THROUGH MONDAY NIGHT.
MONDAY NIGHT THROUGH THURSDAY...GOOD AGREEMENT THAT PRECIPITATION
WILL BE EAST OF THE JAMES RIVER VALLEY BY 12Z TUESDAY FOLLOWED BY
UPPER RIDGING TUESDAY AND WEDNESDAY. WARM AIR ADVECTION RAMPS UP
LATE TUESDAY INTO WEDNESDAY...AHEAD OF AN ADVANCING COLD FRONT WHICH
IS FORECAST TO CROSS SOUTHERN CANADA WEDNESDAY AFTERNOON/EVENING. THE GFS
SHOWS SOME LIGHT PRECIPITATION DEVELOPING IN THE NORTH BEHIND THE
FRONT WEDNESDAY AFTERNOON. THE ECMWF IS ABOUT 6HRS SLOWER WITH THE
COLD FRONT...NOT ARRIVING INTO THE NORTHWEST UNTIL AROUND 00Z
THURSDAY. THURSDAY LOOKS DRY...ALTHOUGH THIS MAY BE BRIEF AS
THE NEXT SYSTEM IS ALREADY APPROACHING THURSDAY NIGHT INTO FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1145 PM CDT THU APR 23 2015
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF
PERIOD. VCTS POSSIBLE NEAR JAMESTOWN AROUND 06Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...AYD
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1136 PM CDT THU APR 23 2015
.UPDATE...
ISSUED AT 1140 PM CDT THU APR 23 2015
NO CHANGES NEEDED FOR THIS UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 321 PM CDT THU APR 23 2015
PRECIP CHANCES AND TYPE TONIGHT AND TOMORROW WILL BE THE MAIN
FORECAST ISSUE FOR THE SHORT TERM.
WEST TO SOUTHWEST FLOW CONTINUES OVER THE REGION WITH VARIOUS WEAK
SHORTWAVES MOVING THROUGH THE FLOW. ONE WEAK LEAD SHORTWAVE HAS
ALREADY BEEN HEADING TOWARDS WESTERN ND...WITH SOME DECENT RADAR
RETURNS OVER THAT PART OF THE STATE. SOME LIGHT RAIN HAS BEEN
REACHING THE GROUND...ALTHOUGH NOT AS MUCH AS RADAR WOULD
INDICATE. DEW POINTS OVER THE CWA HAVE BEEN IN THE SINGLE DIGITS
TO TEENS. THE RAP AND HRRR HAVE THE PRECIP DISSIPATING AS IT MOVES
EAST...WHICH SEEMS REASONABLE GIVEN THE VERY DRY AIR. THINK THE
BETTER SHOT FOR PRECIPITATION WILL BE LATER TONIGHT AS A MORE
SOUTHERN SHORTWAVE MOVES INTO WY AND SFC LOW PRESSURE DEVELOPS
OVER WESTERN SD. THERE WILL BE SOME MID LEVEL WARM AIR
ADVECTION/FRONTOGENESIS OVER MAINLY THE SOUTHERN COUNTIES TONIGHT.
SOME OF THE MODELS HAVE SEVERAL TENTHS OF QPF TONIGHT...BUT GIVEN
HOW LONG IT WILL TAKE TO SATURATE WILL LEAN TOWARDS THE LOWER END
FOR PRECIP AMOUNTS. MODEL SOUNDINGS SHOW MOSTLY ABOVE ZERO AS THE
COLUMN SATURATES...BUT SOME SNOW MIXING IN ON THE NORTHERN EDGE OF
THE PRECIP IS NOT OUT OF THE QUESTION.
TOMORROW...THE SHORTWAVE TROUGH MOVES OUT INTO THE PLAINS...AND
THERE SHOULD BE A DECENT AMOUNT OF PRECIP OVER THE SOUTHERN
COUNTIES SPREADING NORTH AND EAST AS THE BEST MID LEVEL BAROCLINIC
ZONE LIFTS ACROSS THE AREA. CONTINUED TO KEEP LIKELY POPS FOR A
RAIN/SNOW MIX OVER THE SOUTHEASTERN COUNTIES FOR FRIDAY
MORNING...LINGERING INTO THE AFTERNOON. THE CLOUDS AND PRECIP
SHOULD KEEP TEMPS IN THE LOWER 40S IN THE EAST...BUT THINK THERE
WILL BE ENOUGH PEAKS OF SUN TO GET ABOVE 50 IN THE WESTERN
COUNTIES WHERE IT WILL BE DRIER. PRECIP WILL BEGIN TO TAPER OFF
FRIDAY NIGHT BUT KEPT SOME LOWER POPS THROUGH SATURDAY MORNING IN
OUR SOUTHEAST TO COORDINATE WITH NEIGHBORS. CLOUDS AND INCREASING
EASTERLY WINDS WILL KEEP TEMPS IN THE 30S FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 321 PM CDT THU APR 23 2015
SATURDAY AND SUNDAY...UPPER RIDGING WILL BUILD IN BRIEFLY...BUT
GIVE WAY AS THE NEXT SPLIT TROUGH BEGINS TO MOVE OUT FROM THE
WESTERN CONUS BY LATE SUNDAY. SFC HIGH PRESSURE OVER ONTARIO
SATURDAY WILL BRING EAST TO SOUTHEASTERLY WINDS WITH DRIER AIR INTO
THE CWA AND HIGHS SHOULD REACH THE 50S WITH AT LEAST SOME BREAKS
IN THE CLOUDS. TEMPS WILL BE EVEN WARMER FOR SUNDAY AS THE SFC
HIGH MOVES OFF TO THE EAST AND A TROUGH DEVELOPING OVER THE
WESTERN PLAINS STARTS SOME WARMER AIR MOVING BACK TO THE NORTH.
THE ECMWF TRIES TO BRING SOME PRECIP INTO OUR WESTERN COUNTIES FOR
SUNDAY AS THE NEXT UPPER SYSTEM APPROACHES...BUT THE OTHER MODELS
ARE A BIT SLOWER. INCLUDED SOME LOW POPS IN THE DEVILS LAKE BASIN
BUT THINK THE MAIN PRECIP WILL HOLD OFF UNTIL AFTER 00Z MONDAY.
SUNDAY NIGHT THROUGH THURSDAY...LONG WAVE UPPER LEVEL LOW PRESSURE
THAT WAS NORTH OF THE GREAT LAKES WILL MOVE OFF THE NEW ENGLAND
STATES EARLY IN THE PERIOD. BUT LONG WAVE TROUGH BECOMES RE-
ESTABLISHED OVER THE NORTHEAST STATES BY THE END OF THE PERIOD.
LONG WAVE UPPER RIDGE BUILDS OVER THE US AND CANADIAN ROCKIES THIS
PERIOD. ECMWF AND GFS WERE TRENDING FASTER THEN SLOWER OVER THE
LAST COUPLE MODEL RUNS. THE GFS IS FASTER THAN THE ECMWF. SO WILL
PREFER THE SLOWER ECMWF.
KEPT POPS FROM PREVIOUS RUN FOR MON NIGHT THROUGH TUE NIGHT.
APPROACHING UPPER LEVEL TROUGH WILL PRODUCE PRECIP FOR MON AND TUE
AND ANOTHER SHORT WAVE TROUGH IS EXPECTED WED NIGHT THROUGH THU
NIGHT.
HIGH TEMPS WERE INCREASED TWO TO FIVE DEGREES FOR MON TUE AND WED.
HIGH TEMPS DECREASED TWO TO FIVE DEGREES FOR THU FROM THIS MORNINGS
FORECAST PACKAGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1140 PM CDT THU APR 23 2015
EXPECT VFR CIGS TO LOWER INTO MVFR RANGE LATE TONIGHT OR
FRI...AS LOW LEVEL MOISTURE INCREASES. THERE COULD BE A FEW
SHOWERS MAINLY IN THE SOUTH AND EAST. WINDS SHOULD BE FROM THE
E/SE AND COULD GUST OVER 20KT ON FRI.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...JR/HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
416 AM CDT FRI APR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT FRI APR 24 2015
NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION
CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS
IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET
FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA.
MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE
WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS
BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO
SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH
RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR
THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH...
BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR
FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF
THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK
RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH
AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF
HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA.
AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN
THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE
WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE
OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE
SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL
MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND
LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT
IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES
REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER
MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT
ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE
THIS AFTERNOON/EVENING.
FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES
SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT
STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS
HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS
EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER
NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD
ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED
TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST
IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST
MINNESOTA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 415 AM CDT FRI APR 24 2015
ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM
NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS
NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS
AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH
EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW
NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH
DAKOTA.
MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY
FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW
POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL
CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY
IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG
ENOUGH FOR RED FLAG.
MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH
WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME
SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE.
CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE
LIMITED.
LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET
BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO
INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE
WEATHER CONCERNS LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1101 PM CDT THU APR 23 2015
ALTHOUGH VFR IS PREVAILING RIGHT NOW...THE NAM MODEL SOUNDINGS AND
HUMIDITY TIME SECTIONS ARE STILL SHOWING A DETERIORATION OF
CEILINGS INTO THE MVFR CATEGORY FROM SOUTH TO NORTH BETWEEN 06Z
AND 12Z THIS MORNING. THE MVFR SCENARIO BECOMES MORE ENTRENCHED ON
FRIDAY AND FRIDAY EVENING...EXCEPT PERHAPS AT KHON WHO MAY BE IN
THE LOWER END VFR CATEGORY FOR A BULK OF FRIDAY. FOR NOW...ONLY
HAVE THE MENTION OF SHOWERS IN THE TAF FORECASTS. CONDITIONS ARE
STABLE FROM THE SURFACE TO ALMOST 700MB. THERE IS MID LEVEL
INSTABILITY BETWEEN 700-500MB SO IF ANY PRECIPITATION WOULD HAPPEN
TO TAP INTO THAT AIR...THEN SOME ISOLATED THUNDERSTORMS ARE
POSSIBLE. BUT AT THIS TIME...THUNDER CHANCES LOOK TOO SKITTISH TO
MENTION IN THE FORECASTS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1149 PM CDT THU APR 23 2015
.UPDATE...
UPDATED FOR THE 06Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 942 PM CDT THU APR 23 2015/
DISCUSSION...
COOL HIGH PRESSURE HAS SETTLED OVER THE REGION WITH HIGH CLOUDS
STREAMING IN FROM THE WEST. TEMPS ARE IN THE 50S WITH LIGHT WINDS.
NOT MUCH CHANGE OVERNIGHT. TEMPS WILL FALL A FEW DEGREES AND THE
LATEST HRRR IS BRINGING SOME SHRAS TOWARD THE AREA LATE AS THE
WARM FRONT STARTS LIFTING NORTH. CURRENT FORECAST ON TRACK. NO
CHANGES NEEDED.
SJM
PREV DISCUSSION... /ISSUED 239 PM CDT THU APR 23 2015/
CURRENTLY THE MIDSOUTH WAS PARTLY TO MOSTLY CLOUDY WITH A FEW
SPRINKLES STILL LINGERING ON RADAR ACROSS THE SOUTHERN COUNTIES OF
NORTH MISSISSIPPI. TEMPERATURES WERE IN THE LOW TO MID 60S...WITH
NORTH TO NORTHEAST WINDS RANGING FROM 5 TO 10 KTS. ONLY AN
ADDITIONAL DEGREE OR TWO OF WARMING IS EXPECTED TODAY.
FOR TONIGHT...REDUCED RAIN CHANCES TONIGHT AND KEPT THEM MAINLY
WEST OF THE MISSISSIPPI RIVER AS MODELS HAVE SLOWED THE ONSET OF
A LIFTING WARM FRONT. SKIES HOWEVER WILL REMAIN MOSTLY CLOUDY OVER
MOST OF THE REGION...KEEPING TEMPERATURES A BIT MILDER.
FRIDAY AND SATURDAY...CURRENT TROUGH ACROSS THE SOUTHWEST STATES
IS PROGGED TO ADVANCE NORTHEAST TO THE MID MISSISSIPPI VALLEY...
WHILE A SURFACE LOW IN WESTERN KANSAS TRACKS TO THE OHIO RIVER.
THIS SYSTEM IS FORECASTED TO UNDERGO DEEPENING INITIALLY FRIDAY
AND FRIDAY NIGHT...AND THEN MAINTAIN STEADY STRENGTH ON SATURDAY.
A WARM FRONT WILL LIFT NORTH THROUGH THE MIDSOUTH WITH THE THREAT
FOR SHOWERS AND STORMS INCREASING THROUGHOUT THE DAY. BEST CHANCES
FOR RAIN THOUGH WILL ARRIVE FRIDAY EVENING WITH EMBEDDED ELEVATED
THUNDER. QUESTIONS ARISE AFTER MIDNIGHT IF STORMS CAN REFORM NEAR
THE BOUNDARY OR IN THE WARM SECTOR. INSTABILITY APPEARS WEAK BUT
SHEAR IS STRONG. SO AN ISOLATED LARGE HAIL OR DAMAGING WIND REPORT
COULD MATERIALIZE...ESPECIALLY ACROSS THE WEST. BY MID MORNING
SATURDAY A SURGING DRY SLOT WILL BEGIN SHOVING THE LOW LEVEL
MOISTURE INTO MIDDLE TENNESSEE AND NORTHERN ALABAMA. THE MIDSOUTH
COUNTIES WILL HAVE A SMALL WINDOW FOR SEVERE WEATHER AROUND MIDDAY.
THESE STORMS WOULD HAVE A BETTER POTENTIAL FOR LARGE HAIL AND
DAMAGING WINDS AS CAPE CLIMBS TO NEAR 2500 J/KG AND LI`S DROP TO
-9C. UNLESS THE SYSTEM SLOWS CONSIDERABLY THE BEST THREAT ON
SATURDAY WILL BE EAST OF THE MEMPHIS METRO. THE DRY SLOT WILL
PROVIDE FOR GUSTY WINDS...WITH THE STRONG MIXING PROVIDING HIGHS
IN THE 80S. THE DELTA COUNTIES MAY NEED A WIND ADVISORY SATURDAY
AFTERNOON. A WEAK COLD FRONT WILL PASS THROUGH THE MIDSOUTH
SATURDAY NIGHT...BUT LIFT FROM THIS FEATURE WILL BE WEAK WITH ONLY
A FEW STRAY SHOWERS POSSIBLE.
SUNDAY AND SUNDAY NIGHT...SURFACE HIGH PRESSURE WILL BRIEFLY
BUILD INTO THE REGION WITH DRY WEATHER AND MILDER HIGHS.
MONDAY THROUGH WEDNESDAY...A SECOND TROUGH/CLOSED LOW WILL TRACK
ACROSS THE SOUTHERN U.S. THE EURO AND GFS ARE BIT BETTER ALIGNED
ON STORM STRENGTH AND TRACK...WITH THE GFS STILL REMAINING A BIT
FASTER WITH TIMING. A COASTAL SURFACE LOW IS ANTICIPATED TO FORM
AHEAD OF THE UPPER LOW. MOISTURE WILL RETURN TO THE MIDSOUTH WITH
A PERSISTENT LOW LEVEL NORTH TO NORTHEAST FLOW...A MORE WINTER
LIKE PATTERN. CLOUDS AND PERIODS OF RAIN WITH BELOW NORMAL
TEMPERATURES ARE EXPECTED.
JAB
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS WILL CONTINUE INTO FRIDAY WITH CEILINGS GRADUALLY
LOWERING TO MVFR LEVELS FRIDAY AFTERNOON OVER WESTERN SECTIONS OF
THE FORECAST AND BY FRIDAY EVENING OVER THE EAST. SHOWERS AND
THUNDERSTORMS WILL START TO MOVE INTO THE WESTERN PART OF THE
FORECAST AREA BY FRIDAY AFTERNOON WITH MOST AREAS SEEING SOME RAIN
FRIDAY EVENING. WINDS WILL BE MAINLY FROM THE NORTHEAST AROUND 5
KNOTS OVERNIGHT AND THEN BECOME SOUTHERLY AT 5 TO 10 KNOTS FRIDAY
MORNING.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
401 AM CDT FRI APR 24 2015
.DISCUSSION...
AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO
TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR
SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD
SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING
BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A
FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER
WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES
IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT
SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN
OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT.
MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED
2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C
AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850
MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO
EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700
MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST.
AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE
TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK
RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF.
MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE
CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE
WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY
WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z.
THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST
DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND
FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000
AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS
INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF
SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN
OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO
TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE
850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT
NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE
COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN
LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO
MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE
STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE
ENTIRE AREA.
PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY
SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL
EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH
A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH
A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL
LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20
POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL
APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND
OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD
AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES
MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF
THE FRONT. 43
&&
.MARINE...
ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT
CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT
INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY
TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL
PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY
AFTERNOON AND PERSIST INTO TUESDAY NIGHT.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20
HOUSTON (IAH) 84 72 88 70 88 / 40 40 50 10 10
GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
415 AM CDT FRI APR 24 2015
.SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH.
A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND
FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL
INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE
SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN
THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE
DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB
FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE
IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH
SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM
WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER
ARRIVES BY EARLY AFTERNOON.
KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT
PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA.
THIS OCCURS AS A STRONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT
SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB
FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES
INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID
30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH.
SATURDAY... FORECAST CONFIDENCE HIGH.
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY
TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A
RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST...
ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF
VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE
DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB
FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL
BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE
CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN
SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW.
THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE
CANADIAN...ECMWF AND 06Z NAM.
THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE
THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT
WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO.
PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER
WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE
REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING.
EXPECT LOWS TO BE RIGHT AROUND FREEZING.
.LONG TERM...
SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH.
RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY
WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON
THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF
LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S.
TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM.
A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME
LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH
THIS TROUGH THAN THE ECWMF... BUT THEN STALLS THE TROUGH OVER THE
NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL
SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN
TEMPERATURES.
&&
.AVIATION/12Z TAFS/...MIDDLE LEVEL CLOUDS WILL INCREASE ACROSS SRN
WI THIS AFTERNOON AND EVENING ALONG WITH SCT SHOWERS AS A SHORTWAVE
TROUGH MOVES INTO THE AREA. THE LOW LEVELS WILL REMAIN FAIRLY DRY SO
VFR CONDITIONS WILL STILL PREVAIL WITH PERHAPS MVFR VSBYS WITH ANY
HEAVIER SHOWERS THAT MAY OCCUR. THE RAIN WILL BECOME MORE WIDESPREAD
FOR SAT AM AS A STRONGER SHORTWAVE TROUGH AND LOW PRESSURE AREA
MOVES FROM THE CENTRAL GREAT PLAINS TO THE OHIO RIVER VALLEY. SAT AM
IS WHEN THE CIGS WILL DROP TO 1-3.0 KFT AND VSBYS TO 3-5SM WITH THE
WIDESPREAD MDT RAINFALL.
&&
.MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR SAT AND
SAT NT. BRISK ELY WINDS WILL DEVELOP ON SAT AS THE PRESSURE GRADIENT
TIGHTENS BETWEEN POLAR HIGH PRESSURE OVER SRN CANADA AND LOW
PRESSURE MOVING FROM THE CENTRAL GREAT PLAINS INTO THE MIDDLE MS
RIVER VALLEY. THE WINDS WILL TURN NELY FOR SAT AFT AND NIGHT AS THE
LOW TRACKS ACROSS THE OHIO RIVER VALLEY. WAVE HEIGHTS WILL BUILD TO
3 TO 5 FEET DURING THIS TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
SATURDAY THROUGH THURSDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
333 AM CDT FRI APR 24 2015
.SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH.
A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND
FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL
INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE
SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN
THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE
DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB
FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE
IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH
SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM
WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER
ARRIVES BY EARLY AFTERNOON.
KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT
PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA.
THIS OCCURS AS A STONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT
SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB
FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES
INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID
30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH.
SATURDAY... FORECAST CONFIDENCE HIGH.
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY
TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A
RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST...
ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF
VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE
DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB
FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL
BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE
CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN
SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW.
THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE
CANADIAN...ECMWF AND 06Z NAM.
THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE
THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT
WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO.
PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER
WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE
REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING.
EXPECT LOWS TO BE RIGHT AROUND FREEZING.
.LONG TERM...
SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH.
RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY
WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON
THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF
LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S.
TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM.
A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME
LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH
THIS TROUGH THAN THE ECWMF... BUT THEN STALLS THE TROUGH OVER THE
NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL
SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN
TEMPERATURES.
&&
.AVIATION/12Z TAFS/...COMING SOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
SATURDAY THROUGH THURSDAY...MRC
AREA FORECAST DISCUSSION
NWS TUCSON AZ
850 AM MST FRI APR 24 2015
.SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL MOVE ACROSS THE STATE
TODAY...RESULTING IN A CHANCE OF SHOWERS AND THUNDERSTORMS MAINLY
FROM TUCSON WEST AND NORTH. DRY CONDITIONS WILL PREVAIL AREA-WIDE ON
SATURDAY. A STRONG LOW PRESSURE SYSTEM WILL THEN MOVE INTO THE
REGION SATURDAY NIGHT AND SUNDAY. THIS SYSTEM WILL BRING GUSTY
WINDS...COOLER TEMPERATURES AND A GOOD CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS TO THE EASTERN HALF OF SOUTHERN ARIZONA
SATURDAY NIGHT AND SUNDAY. DRY CONDITIONS WILL RETURN TO START THE
WORK WEEK...ALONG WITH A STRONG WARMING TREND TUESDAY THROUGH
THURSDAY.
&&
.DISCUSSION...ISOLATED SHOWERS HAVE DEVELOPED THIS MORNING AS UPPER
LEVEL TROF MOVES ACROSS THE AREA. LATEST HRRR RUNS INDICATE THAT
ISOLATED SHOWERS WILL BE AROUND MAINLY FROM TUCSON WEST AND NORTH
INTO THE AFTERNOON HOURS. HAVE UPDATED THE FORECAST FOR THIS MORNING
TIME FRAME TO ADD ISOLATED SHOWERS...MAINLY FROM TUCSON WEST AND
NORTH...AND WILL CONTINUE TO LOOK AT NEW MODEL DATA FOR THE
AFTERNOON PART OF THE TODAYS FORECAST SHORTLY.
&&
.AVIATION...VALID THRU 25/18Z. SCT-BKN CLOUD DECKS 5-8 KFT AGL
PRIMARILY NW OF KFHU-KCLT LINE WITH ISOLATED -SHRA/TS THROUGH
25/03Z. LIGHT WINDS LESS THAN 10 KTS...THEN SWLY TO WLY WINDS OF 12-
20 KTS WITH OCCASIONAL GUSTS TO 30 KTS THIS AFTERNOON WITH THE
HIGHEST WIND SPEEDS SOUTH AND EAST OF KTUS. CLEARING SKIES ALONG
WITH TYPICAL DIURNAL WINDS DEVELOPING AFTER 25/03Z. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED SHOWERS...POSSIBLY A THUNDERSTORM...FROM
TUCSON WEST AND NORTH TODAY. IN ADDITION...BREEZY WEST TO SOUTHWEST
WINDS OF 15 TO 20 MPH WITH AN OCCASIONAL GUST TO 35 MPH WILL DEVELOP
AGAIN THIS AFTERNOON. THE STRONGEST WINDS WILL OCCUR SOUTH AND EAST
OF TUCSON. ANY SHOWERS OR STORMS WILL BE CAPABLE OF PRODUCING BRIEF
GUSTY AND ERRATIC WINDS. DRY CONDITIONS ARE EXPECTED TONIGHT AND
SATURDAY.
THEREAFTER...ANOTHER STORM SYSTEM WILL APPROACH THE REGION WHICH
WILL BRING ANOTHER ROUND OF ELEVATED WINDS AND A CHANCE OF SHOWERS
AND THUNDERSTORMS SATURDAY NIGHT THROUGH SUNDAY. THIS AREA OF
DISTURBED WEATHER WILL QUICKLY EXIT THE AREA RESULTING IN DRY
CONDITIONS RETURNING SUNDAY NIGHT THROUGH THE END OF NEXT WEEK.
A SUBSTANTIAL WARMING TREND IS ANTICIPATED STARTING MONDAY...WITH
CURRENT INDICATIONS POINTING TO HIGH TEMPERATURES INCREASING TO 6-12
DEGREES ABOVE NORMAL BY THE END OF THE WEEK.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1130 AM EDT FRI APR 24 2015
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS DEEP TROUGHING THROUGH
THE DESERT SOUTHWEST INTO NORTHERN MEXICO...FOLLOWED DOWNSTREAM BY
AMPLIFIED RIDGING ACROSS THE GULF OF MEXICO AND DEEP SOUTH STATES.
MOIST SUBTROPICAL JET IS RIDING NORTHWARD BETWEEN THESE TWO
FEATURES OVER THE SOUTHERN PLAINS BEFORE TURNING EASTWARD ACROSS
THE SOUTHEAST CONUS. THE FLORIDA PENINSULA RESIDES ON THE EASTERN
PERIPHERY OF THE UPPER RIDGE WHERE OUR DEEP LAYER WINDS PER 12Z
KTBW SOUNDING PROFILE WERE FROM THE NORTHWEST. SOUNDING DID SHOW A
BIT OF A SUBSIDENCE INVERSION ASSOCIATED WITH THE UPPER RIDGE
AROUND 700MB...WITH A MOIST PROFILE BELOW THIS LEVEL TO THE
SURFACE.
AT THE SURFACE...
1020MB CONTINENTAL HIGH PRESSURE RIDGING DOWN INTO THE SOUTHEAST
CONUS HAS PUSHED A WEAK FRONTAL BOUNDARY DOWN INTO THE CENTRAL
FLORIDA PENINSULA. SEEING A BIG GRADIENT IN SURFACE DEWPOINTS
ACROSS THIS BOUNDARY WITH LOWER TO MIDDLE 70S SOUTH OF THE I-4
CORRIDOR...AND THEN QUICKLY DROPPING TO READINGS IN THE 40S UP
TOWARD THE I-10 CORRIDOR. THE GENERAL LOCATION OF THE BOUNDARY CAN
ALSO BE EASILY SEEN WITH VISIBLE SATELLITE IMAGERY...WHERE A
DEFINED CUMULUS DEVELOPMENT CUTOFF IS LOCATED VERY NEAR I-4. SOUTH
OF THIS LINE...DIURNAL HEATING IS WORKING WITH THE GREATER
BOUNDARY LAYER MOISTURE TO FORM THE SCT-BKN CUMULUS FIELD...WHILE
NORTH THE MOISTURE IS SIMPLY NOT IN PLACE TO EFFICIENTLY PRODUCE
THE CLOUDS.
REGIONAL RADARS SHOW A FEW SHOWERS OVER THE COASTAL WATERS ALONG
THIS BOUNDARY...BUT SO FAR NOTHING MORE THAN A FEW SPRINKLES OVER
LAND. WILL SEE SOME DEVELOPMENT TO THE SOUTH OF I-4 THIS
AFTERNOON...BUT SHOULD NOT BE ANYTHING LIKE THE DEGREE OF
CONVECTION EXPERIENCED IN MANY SPOTS DURING THURSDAY.
REST OF TODAY...
THE FORECAST WILL BE SPLIT NORTH TO SOUTH BY THE BOUNDARY NEAR THE
I-4 CORRIDOR. NORTH OF THIS BOUNDARY...THE LACK OF BL MOISTURE
MAKES INSTABILITY REALLY LACKING AND DO NOT HAVE THUNDERSTORM
MENTION IN THE FORECAST. IN FACT...NONE OF THE HIGH RESOLUTION
CONVECTION ALLOWING MODEL MEMBERS ARE PRODUCING ANY RAIN OVER
THESE NORTHERN ZONES...SO THE CURRENT FORECAST LOOKS ON TRACK.
SOUTH OF THE I-4 CORRIDOR...THE EVENTUAL DEVELOPMENT OF THE SEA-
BREEZE SHOULD PROVIDE THE FOCUS FOR A FEW SCT LATE DAY STORMS.
HAVE INCREASED POPS TO AROUND 20% AS FAR NORTH AS POLK COUNTY
ALONG THE SOUTHERN EDGE OF THE BOUNDARY...AND HAVE CHANCE 30-40%
POPS OVER THE SOUTHERN ZONES (MAINLY AWAY FROM THE BEACHES). A
SHOWER OR STORMS IS POSSIBLE RIGHT AT THE COAST...HOWEVER THE
SEA-BREEZE SHOULD MAKE SOME PROGRESS INLAND...AND MOST OF THE
RELIABLE GUIDANCE FAVORS AREAS AWAY FROM THE COAST.
TONIGHT...
ANY ISOLATED EVENING STORMS WILL DISSIPATE QUICKLY WITH THE LOSS
OF DIURNAL HEATING. UPPER RIDGE AXIS WILL BE SHIFTING EASTWARD AND
BE CENTERED OVER THE EASTERN GULF OF MEXICO BY EARLY SATURDAY
MORNING. SEVERAL UPPER LEVEL SHORTWAVE FEATURES WILL COMBINE WITH
EFFICIENT WAA REGIME TO RESULT IN AN ACTIVE CONVECTION NIGHT
ACROSS THE LOWER MS VALLEY OVER TO AL/GA. HOWEVER...HIGH PRESSURE
SHIFTING OFF THE EASTERN SEABOARD WILL RIDGE BACK TO THE SOUTHWEST
OVER OUR HEADS. THIS STACKED RIDGING REGIME SHOULD BE PLENTY TO
PROTECT OUR ZONES AND KEEP THIS INCLEMENT WEATHER WELL TO OUR
NORTH AND NORTHWEST THROUGH THE OVERNIGHT.
SATURDAY...
STRONG SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW WILL EJECT OUT
OF THE CENTRAL PLAINS INTO THE OHIO/TN VALLEYS...WHILE A SERIES OF
WEAKER IMPULSES RIDE EASTWARD ALONG THE NORTH-CENTRAL GULF COAST.
THE MOVEMENT OF THESE MASS FIELDS WILL RESULT IN A DE-
AMPLIFICATION OF THE UPPER RIDGE OVER OUR REGION THROUGH THE DAY.
WARM FRONTAL BOUNDARY WILL BE ALIGNED TO THE NORTH OF THE I-4
CORRIDOR WITH QUITE A BIT OF ONGOING SHOWER AND STORM ACTIVITY
FROM THE FLORIDA PANHANDLE TO AL/GA. THE QUESTION FOR OUR FORECAST
WILL BE HOW THE WEST COAST SEA-BREEZE BEHAVES THROUGH THE DAY.
GENERALLY SPEAKING...THE GOOD SYNOPTIC SETUP FOR LIFT WILL REMAIN
TO OUR NORTH TOMORROW...BUT WE WILL HAVE THE SEA-BREEZE TO PROVIDE
AT LEAST SOME FOCUS. WIND FIELDS EVOLVE FAVORABLY TOWARD ORGANIZED
CONVECTIVE POTENTIAL DURING THE DAY...WITH 0-6KM SHEAR VALUES
ELEVATING TO BETWEEN 40-45 KNOTS OVER OUR NORTHERN AREAS FOR THE
SECOND HALF OF THE DAY. THESE VALUES...ALTHOUGH NOT EXTREME...ARE
CAPABLE OF SUSTAINING ORGANIZED CONVECTION. HERE IS THE PROBLEM
FOR OUR AREA...THE 1000-700MB FLOW TOMORROW IS FROM THE W/SW AT
15-25 KNOTS. FIRST OF ALL...THIS WILL KEEP THE WEST COAST SEA-
BREEZE FAIRLY WEAK AND DISORGANIZED. SECOND...THE BOUNDARY WILL
VERY QUICKLY TRANSLATE INLAND. WITH THIS IN MIND...CURRENT
THINKING IS THAT THE BEST CHANCES FOR AFTERNOON THUNDER WOULD BE
OVER TOWARD THE FLORIDA EAST COAST...WHERE SEA-BREEZE COLLISION
WILL TAKE PLACE. IT IS A TOUGH CALL SINCE ANY CONVECTION THAT
DOES DEVELOP WILL BE MOVING QUICKLY AND MAY PRODUCE LOCALLY
DAMAGING WINDS...BUT THE OVERALL COVERAGE LOOKS MUCH GREATER EAST
AND NORTH OF OUR ZONES. WILL TAKE A CLOSE LOOK AT THE 12Z GUIDANCE
PACKAGE AND SEE IF THIS "EAST COAST" PHILOSOPHY STILL SEEMS VALID.
&&
.AVIATION...
PERIODS OF MVFR CIGS THIS MORNING AS THE BKN CUMULUS FIELD FILLS
IN. THESE CIGS WILL RISE ABOVE VFR LEVELS TOWARD MIDDAY...WITH
GENERAL VFR CONDITIONS THEN ANTICIPATED THROUGH THE EVENING HOURS.
ONLY EXCEPTIONS WILL BE IN THE VICINITY OF ISOLATED TO SCATTERED
PM STORMS ALONG THE SEA-BREEZE. BEST CHANCES AT A LATE DAY STORM
WILL BE SOUTH OF THE I-4 CORRIDOR TERMINALS.
&&
.MARINE...
NORTHERLY WINDS WILL BE IN PLACE THROUGH TODAY WITH A
TURN ONSHORE EXPECTED NEAR THE COAST IN THE AFTERNOON AS THE SEA
BREEZE DEVELOPS. FLOW WILL BECOME MORE SOUTHEAST AND THEN
SOUTHWEST AND WEST TONIGHT INTO SATURDAY AFTERNOON AS HIGH
PRESSURE SINKS TO THE SOUTHEAST. WIND SPEEDS WILL BRIEFLY APPROACH
CAUTIONARY LEVELS TONIGHT AND SUNDAY NIGHT FOR THE NORTHERN
WATERS...BUT WILL OTHERWISE REMAIN AROUND 15 KNOTS OR LESS THROUGH
THE WEEKEND.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS AS RELATIVE HUMIDITY VALUES REMAIN ABOVE
CRITICAL LEVELS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 87 73 84 75 / 20 10 10 10
FMY 90 73 87 75 / 20 10 10 0
GIF 88 70 87 72 / 20 10 20 10
SRQ 87 72 83 75 / 20 0 0 10
BKV 87 66 86 70 / 10 0 20 10
SPG 86 75 85 76 / 20 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE/FIRE WEATHER...14/MROCZKA
DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
930 AM EDT FRI APR 24 2015
.DISCUSSION...
CURRENT-THIS AFTERNOON...FRONTAL TROUGH JUST ENTERING CENTRAL
FLORIDA PER THE 0900Z SURFACE ANALYSIS. THE TROUGH WILL WORK ITS WAY
DOWN THE FORECAST AREA AND IS FORECAST TO BE CLEAR OF THE SOUTHERN
COUNTIES THIS EVENING. ACCOMPANYING WIND SHIFTS FROM THE NORTHWEST
TO THE NORTH THEN NORTHEAST THIS AFTERNOON AND EVENING AS THE TROUGH
CLEARS AND HIGH PRESSURE BUILDS IN FROM THE NORTH.
FIRST COUPLE OF VISIBLE SATELLITE IMAGES SHOWING NOT MUCH IN THE WAY
OF MARINE STRATOCUMULUS IN THE NORTHEAST WINDFLOW OFF NORTHEAST
FLORIDA...GEORGIA AND THE CAROLINAS.
ANY CHANGE(S) TO BE MADE TO THIS AFTERNOON`S FORECAST WOULD BE TO
CLOUDS AND THE WIND DIRECTION/SPEED WHICH ARE DEPENDENT ON HOW FAST
THE FRONTAL TROUGH MOVES DOWN THE PENINSULA.
.AVIATION...MORNING LOW CLOUDS...IFR INITIALLY THEN MVFR WITH
HEATING OF THE LOWER LAYERS... FROM ORLANDO INTERNATIONAL (MCO)
SOUTH MOVE SOUTH AND CLEAR THE AREA AS THE WINDS SHIFT FROM
NORTHWEST TO THE NORTH THEN EVENTUALLY NORTH LATE TODAY/THIS EVENING.
.MARINE...THE NOAA BUOYS WERE RECORDING NORTHWEST WINDS 12 TO 14
KNOTS AT 20NM AND 8 KNOTS AT 120NM AND 2 TO 3 FOOT SEAS AT BOTH THE
NOAA BUOYS AND THE TWO SCRIPPS BUOYS AT 4 AND 6NM OFF THE BEACH. THE
MAYPORT CMAN SITE ALREADY NORTHEAST AND THE SAINT AUGUSTINE SITE
NORTH. TRIDENT PIER IN PORT CANAVERAL...BUOY 009 AND SEBASTIAN INLET
CMAN SITES STILL NORTHWEST BUT SHOULD SHIFT TO THE NORTH DURING THE
AFTERNOON.
WINDS SHOULD PICK UP TO NORTHWEST 15 TO 20 KNOTS WELL OFFSHORE THIS
AFTERNOON AS THE LEADING EDGE OF THE HIGHER PRESSURE BUILDS IN. THIS
WILL PROMPT AN SMALL CRAFT OPERATORS EXERCISE CAUTION FOR WINDS
SEBASTIAN INLET NORTH.
PREVIOUS DISCUSSION
THE TAIL END OF A FRONTAL TROUGH PASSING OFFSHORE THE SE STATES WILL
PASS OVER ECFL WITH LITTLE FANFARE DURING THIS MORNING. LOCAL WINDS
WILL RESPOND BY VEERING FROM WLY COMPONENT AT DAYBREAK TO NORTH THEN
NORTHEAST DURING THE AFTERNOON AS HIGH PRESSURE BUILDS INTO THE AREA
BEHIND THE DEPARTING BOUNDARY. AN APPROACHING RIDGE EMBEDDED WITHIN
THE PROGRESSIVE WLYS WL BRING WARM CONDS IN THE MID TO UPR 80S
ACROSS THE BULK OF THE AREA. RECENT HRRR GUID SUPPORTED BY GFS MOS
SHOWS A SMALL RAIN CHC ALONG THE SPACE CST AND TREASURE CST TO LAKE
OKEE DURING THE HEAT OF THE AFTERNOON AS THE ONSHORE WINDS COMBINES
WITH SFC HEATING AND SOME MODEST MOISTURE TO CREATE ISOLD SHOWERS
AND A FAST MOVING STORM OR TWO. PRECIP CHCS WL RANGE FROM
UNMENTIONED WEST OF THE I-4 CORRIDOR TO AROUND 20 PERCENT ACROSS THE
SOUTH. RAIN CHCS LARGELY TIED TO SFC HEATING AND BOUNDARY
INTERACTION WL DIMINISH AFTER NIGHTFALL. LOWS WILL MAKE IT TO THE
UPR 60S TO AROUND 70.
SAT...SURFACE HIGH CONTINUES TO SLIDE AWAY FROM THE SOUTHEAST COAST
INTO THE ATLANTIC AS THE NEXT SYSTEM MOVES ACROSS THE OH/TN VALLEYS
AND OFF THE CAROLINA COAST INTO LATE WEEKEND.
WHILE MODELS SHOW OVERALL MOISTURE WILL BE SUFFICIENT FOR SCATTERED
SHOWERS AND STORMS WITH PWATS 1.6-18"...FORECAST SOUNDINGS SHOW SOME
DRIER AIR LINGERING IN THE 850-500MB LEVEL...ESPECIALLY ON
SAT...WHICH MAY HELP DELAY CONVECTIVE ONSET UNTIL LATER IN THE
AFTERNOON. HOWEVER ANY LINGERING DRY AIR WILL ENHANCE THE WIND
THREAT FROM STRONG STORMS ESPECIALLY GIVEN THE MID LAYER WESTERLY
FLOW OF 45-55 KNOTS WITH WINDS EVEN IN THE 925-850MB LAYER
APPROACHING 30KTS.
SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER
A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS THE
MAIN HAZARD GIVEN THE BRISK STORM MOTION. A FEW ROTATING STORMS WILL
NOT BE OUT OF THE QUESTION ESPECIALLY NEAR THE COAST AS MODELS HINT
AT THE EAST COAST SEA BREEZE BOUNDARY TRYING TO FORM RIGHT ALONG THE
IMMEDIATE COAST LATE IN THE DAY.
ISOLATED SHOWERS POSSIBLE TOWARDS DAYBREAK SUNDAY AS THE FRONT EDGES
A LITTLE FURTHER SOUTH AND WEST FLOW INCREASES...BRINGING SOME
ACTIVITY FROM OFF THE GULF ACROSS THE PENINSULA.
TEMPERATURES CONTINUE ABOVE NORMAL IN THE UPPER 80S AND LOW 90S WITH
LOWS IN THE 70S.
SUNDAY...WEAK FRONTAL BOUNDARY DROPS INTO N FLORIDA WITH LITTLE
SOUTHWARD PROGRESS INTO SUNDAY EVENING. THERE WILL BE A LITTLE
BETTER MOISTENING IN THE MID LEVEL GIVEN THE CLOSER PROXIMITY OF THE
FRONT WITH BRISK WESTERLY FLOW INCREASING AS SPEEDS AT 925MB COME UP
TO 20-30 KNOTS AND 50-55 KNOTS AT 500MB.
GIVEN THE STRENGTH OF THE FLOW...NO SEABREEZE DEVELOPMENT IS
EXPECTED AND TEMPS WILL BE A FEW DEGREES WARMER...GENERALLY AROUND
90 OR LOW 90S IN MOST LOCATIONS.
EXPECT AN EARLY START TO CONVECTION WITH STORMS PROGRESSING QUICKLY
FROM WEST TO EAST ACROSS E CENTRAL FL IN THE LATE MORNING AND
AFTERNOON HOURS. AS WITH SATURDAY...SPC HAS THE AREA FROM BREVARD
AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX
WITH ISOLATED SEVERE WIND GUSTS CONTINUING TO BE THE MAIN HAZARD.
THE PROXIMITY OF THE FRONT AND BRISK FLOW MAY ALLOW AND GULF
ACTIVITY OVERNIGHT TO CONTINUE TO MOVE ACROSS THE PENINSULA...MAINLY
IN THE FORM OF SHOWERS.
MON-THURS...UNSETTLED PATTERN FOR THE FIRST HALF OF THE WEEK AS THE
WEEKEND`S FRONTAL BOUNDARY MEANDERS DOWN THE PENINSULA DURING THE
DAY ON MONDAY BEFORE STALLING/WASHING OUT ACROSS S FLORIDA LATE IN
THE DAY. ROBUST UPPER LEVEL LOW THAT MOVES INTO THE SOUTHERN PLAINS
ON MONDAY WILL SLOWLY PHASE WITH A NORTHERN STREAM SHORTWAVE AS IT
MOVES INTO THE EASTERN US WEDNESDAY AND THURSDAY.
AT THE SURFACE...WEAK BOUNDARY LIFTS BACK NORTH INTO TUESDAY AS
130KT JET SLIDING ACROSS THE NORTHERN GULF OF MEXICO HELPS SPAWN AN
ASSOCIATED SURFACE LOW THAT TRACKS ACROSS N FLORIDA/GA LATE
WEDNESDAY OR THURSDAY. WHILE THE GFS AND ECMWF SHOW THE SAME BROAD
SOLUTION...SOME DIFFERENCES IN TIMING AND EVOLUTION OF THE UPPER
LEVEL FEATURES TRANSLATE INTO LARGER DIFFERENCES IN THE STRENGTH OF
THE SURFACE LOW.
GFS HAS SWUNG BACK TOWARDS A DRIER SOLUTION ON MONDAY...BUT WILL
KEEP WITH PREVIOUS RUNS AND KEEP SCT POPS IN THE FORECAST WITH
ACTIVITY FOCUSED TOWARDS THE FAR WESTERN INTERIOR...OKEECHOBEE AND
TREASURE COAST GIVEN THE LOW LEVEL NE PUSH THAT OCCURS BEHIND THE
BOUNDARY.
CONSENSUS BETWEEN GFS AND ECMWF STILL KEEP 40-60 PERCENT POPS IN THE
FORECAST FOR TUES AND WED AS WEST-SOUTHWEST FLOW TAPS INTO
SUBTROPICAL MOISTURE AND PWATS COME UP TO CLOSE TO 2". WIND FIELDS
WILL SUPPORT A FEW BREEZY DAYS DURING THE PERIOD WITH THE POSSIBILITY
FOR SOME GUSTY STORMS AS WELL.
SURFACE LOW PULLS OUT INTO THE ATLANTIC WED NIGHT AND FRONT MOVING
THROUGH THE REGION. A FEW SHOWERS MAY LINGER DEPENDING ON THE SPEED
OF THE FRONT INTO THURSDAY.
&&
.AVIATION...
COTD VFR CONDS THE NEXT 24H OVER MOST SITES WITH EXCEPTION OF
SOME PSBL CIGS NR FL 040 AND ISOLD SHRA FM VRB-FPR-SUA-OKE. FM
24/15Z-24/22Z.
&&
.MARINE...
TODAY AND TONIGHT...PSG OF THE FRONTAL TROUGH OVER THE WATERS THIS
AM WI BRING CHANGING WIND CONDS FROM MORNING INTO THE AFTERNOON.
MAIN CONCERN WL BE DEVELOPING NLY TO ONSHORE WIND DURING AFTERNOON
WHICH WL INCREASE WAVE HGHTS ALONG WITH BRINGING A WIND CHOP TO
LCL WATERS. HEADLINES ARE NOT ANTICIPATED ATTM...HOWEVER SEA STATE
WL BEGIN TO RAMP UP ONCE THE NLYS BEHIND THE FRONTAL TROUGH MOVES
INTO THE AREA THIS AFTERNOON.
SAT-SUN...S/SW WINDS WILL INCREASE TO 15-20 KNOTS SAT AFTERNOON AS
GRADIENT INCREASES BETWEEN DEPARTING SURFACE HIGH AND SYSTEM MOVING
ACROSS OH/TN VALLEYS. WINDS VEER MORE W/SW INTO SUNDAY AS FRONT
DROPS INTO NORTH FLORIDA WITH WINDS CONTINUING 15-20KTS. SEAS WILL
INCREASE UP TO 4-5 FT OFFSHORE INTO SUNDAY WITH PERIODS SHORTENING
DUE TO THE SHORT FETCH. BOATERS SHOULD BE PREPARED FOR SCATTERED
STRONG STORMS APPROACHING FROM THE WEST QUICKLY THIS WEEKEND.
MON-WED...FRONT SLIDES THROUGH LATE ON MONDAY WITH WINDS VEERING
NORTH THEN NORTHEAST 10-15KTS. BOUNDARY LIFTS BACK INTO REGION INTO
TUESDAY WITH WINDS VEERING EAST-SOUTHEAST...THEN INCREASING OUT OF
THE SOUTH-SOUTHWEST LATE ON WEDNESDAY AS SURFACE LOW IS FORECASTED
TO TRACK ACROSS NORTH FLORIDA. POTENTIAL WILL REMAIN FOR SCATTERED
OFFSHORE MOVING STRONG STORMS INTO MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 80 68 85 72 / 10 10 30 20
MCO 86 70 87 71 / 10 10 30 10
MLB 82 71 87 72 / 20 10 30 20
VRB 82 69 87 72 / 20 10 20 10
LEE 86 70 84 73 / 10 10 30 20
SFB 84 69 86 74 / 10 10 30 20
ORL 85 70 86 72 / 10 10 30 20
FPR 84 69 88 71 / 20 10 20 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
LONG TERM/IMPACT WX...JOHNSON
SHORT TERM/AVIATION...WIMMER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
620 AM CDT FRI APR 24 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT FRI APR 24 2015
A SHARP INCREASE IN SURFACE MOISTURE SHOULD BE NOTICED ACROSS
WESTERN KS AS BOUNDARY LAYER MOISTURE TRANSPORT INCREASES IN
RESPONSE TO A DEEPENING LEE SURFACE LOW EXPECTED TO TRACK FROM
EASTERN CO TO NORTHEAST KS BY LATER TONIGHT. THIS INCREASED SURFACE
MOISTURE MIGHT LEAD TO A FEW AREAS OF DRIZZLE AS THE MODELS INDICATE
THIS MORNING, BUT MORE IMPORTANTLY CONTRIBUTE TO MUCH HIGHER
SURFACE BASED CAPES BY THE EARLY AFTERNOON. A DRYLINE WILL BE
PRESENT TO AID IN CONVECTIVE INITIATION AS EARLY AS THE 18 TO 20 UTC
TIMEFRAME.
WITH RESPECT TO CONVECTIVE THREATS, HAIL WILL BE THE MAIN THREAT AT
LEAST EARLY IN THE EVENT. A TORNADO RISK IS ALSO A POSSIBILITY GIVEN
THE DEEP SHEAR AND STEEP LOW LEVEL LAPSE RATES/HIGH SURFACE DEW
POINTS. THE PARALLEL FLOW TO THE BOUNDARY MIGHT SUGGEST LONG TRACK
TORNADOES AREA NOT LIKELY, BUT BRIEF TORNADOES THE MORE LIKELY
SCENARIO. ISOLATED, DISCREET STORMS SHOULD BEGIN THE EVENT ALONG THE
DRYLINE WITH VERY LARGE HAIL POTENTIAL; EASILY IN THE 2 TO 3 INCH
RANGE, AND POTENTIALLY EVEN HIGHER. THE LATEST 4 KM NAM CONVECTIVE
SCHEME SUGGESTED THE MORE DISCREET STORMS MORPHING INTO CLUSTER OR
SMALL LINES IN CENTRAL KANSAS BY THE EVENING, SUGGESTING POSSIBILITY
FOR NOT ONLY SEVERE OUTFLOW, BUT HEAVY RAIN AND LOCALIZED FLOODING.
THE UPPER LOW WILL BECOME STACKED SOMEWHERE NEAR KANSAS CITY BY
EARLY SATURDAY MORNING, LEAVING WESTERN KANSAS IN A DEEP
NORTHWESTERLY FLOW WITH LIGHT WEST SURFACE WINDS. NEGATIVE VORTICITY
ADVECTION AND DOWNSLOPE CONDITIONS SHOULD PROMOTE CLEARING SKIES
OVERNIGHT INTO SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE
RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS
A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE
A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB
TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE
MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S
IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE
OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME
NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS
BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT
WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING
UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL
MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH
EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR
PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF
ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE
MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD
COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN
HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE
OKLAHOMA BORDER.
FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO
CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS
SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY
TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS
BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST.
GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO
WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN
KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE
SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN
BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE
MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS
ALONG THE LEE OF THE ROCKIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 618 AM CDT FRI APR 24 2015
A MOIST UPSLOPE SOUTHEASTERLY FLOW WILL BECOME SOUTHWEST AT 10 TO
15 KNOTS DURING THE DAY AS A WARM FRONT LIFTS NORTH ACROSS
SOUTHWEST KANSAS. BASED ON THE 06Z NAM AND THE LATEST HRRR AND RAP
THE IFR/LIFR CEILINGS AND AREAS OF MVFR FOG WILL ERODE BETWEEN 13Z
AND 16Z AT GCK AND DDC. HYS WILL LIKELY REMAIN IN THE STATUS AND
PATCHY FOG UNTIL AROUND 17Z FRIDAY. SCATTERED AFTERNOON
THUNDERSTORMS WILL THEN BE POSSIBLE FROM DDC NORTH AND EAST AS AN
UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS. GIVEN THE HIGHER
PROBABILITY FOR AFTERNOON THUNDERSTORMS AT DDC AND HYS WILL INSERT
A PREVAILING PERIOD OF VCTS IN THIS LOCATION. TONIGHT SKIES WILL
CLEAR AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL DISTURBANCE AS
MOVES INTO CENTRAL KANSAS. WEST TO NORTHWEST WINDS WILL BE AT 10
TO 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 50 79 48 / 50 10 10 10
GCK 77 48 78 48 / 40 10 10 10
EHA 76 48 79 47 / 30 10 10 10
LBL 80 49 81 48 / 30 10 10 10
HYS 73 51 73 46 / 60 50 10 20
P28 82 53 81 52 / 40 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS PADUCAH KY
627 AM CDT FRI APR 24 2015
.UPDATE...
ISSUED AT 625 AM CDT FRI APR 24 2015
THE AVIATION SECTION HAS BEEN UPDATED FOR THE 12Z TAF ISSUANCE.
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
SEVERAL CHALLENGES TO THE FORECAST FOR THIS PART OF THE PACKAGE.
MID-HIGH LEVEL CLOUDS STREAMING ACROSS THE AREA EARLY THIS MORNING
AND SATELLITE SUGGESTS PATCHY MID-HIGH LEVEL CLOUDS WILL CONTINUE
THROUGH MOST OF THE DAY. SEVERAL SMALL PIECES OF ENERGY HEADED OUR
WAY TODAY. HRRR MODEL PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN SECTIONS LATER THIS MORNING AND THESE ARE SLOWLY
EXPECTED TO SPREAD EAST LATE THIS AFTERNOON.
BY TONIGHT A WARM FRONT WILL DEVELOP TO OUR SOUTH. CURRENT WATER
VAPOR IMAGES DEPICT MOISTURE STREAMING NORTHEAST OUT OF OLD MEXICO
AND TEXAS. SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE WIDESPREAD
TONIGHT ACROSS THE AREA.
ON SATURDAY...THERE SHOULD BE A LULL IN THE ACTION DURING THE
MORNING HOURS AS THE MAIN PRECIP ENDS FROM SOUTHWEST TO NORTHEAST.
THE CLOUDS ARE EXPECTED TO BREAK UP FOR SEVERAL HOURS DURING THE
MORNING HOURS ESPECIALLY OVER THE CENTRAL AND SOUTHERN SECTIONS.
AS THIS HAPPENS, MOST OF THE AREA WILL BECOME VERY UNSTABLE AS
WIND FIELDS BECOME MORE FAVORABLE FOR SEVERE WEATHER DURING THE
AFTERNOON HOURS. SPC HAS A MAJORITY OF THE AREA IN AN ENHANCED
RISK AND THIS SEEMS PRUDENT AS CONFIDENCE LEVELS CONTINUE TO
INCREASE FOR SEVERE WEATHER. VERY FAVORABLE LAPSE RATES SHOULD
ALLOW DEEP CONVECTION TO BEGIN BY EARLY-MID AFTERNOON. 0-3 KM
BULK SHEAR VECTORS WILL RANGE FROM 35 TO 40 KTS AS LOW LEVEL WINDS
INCREASE...ESPECIALLY OVER WEST KENTUCKY.
THERE IS POTENTIAL FOR LARGE HAIL...DAMAGING WINDS...AND A FEW
TORNADOES TOMORROW AFTERNOON AND EARLY EVENING ESPECIALLY OVER
WESTERN KENTUCKY.
PRECIPITATION SHOULD END SATURDAY NIGHT WITH SOME SUNSHINE ON
SUNDAY.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
SLIGHTLY BETTER FORECAST CONFIDENCE IN THE LONG TERM.
VIRTUALLY ALL OF THE WEATHER...OR LACK THEREOF...IN THE LONG TERM
PERIOD HINGES ON THE DEVELOPMENT AND EVOLUTION OF A STORM SYSTEM
FORECAST TO MOVE OUT OF THE SOUTHERN PLAINS.
THE GFS CONTINUES TO TRACK THIS SYSTEM EAST NORTHEASTWARD BRINGING
IT AND ITS ASSOCIATED PRECIPITATION SLIGHTLY FARTHER NORTH THEREBY
AFFECTING THE SOUTHERN HALF OF OUR CWA TUESDAY AND TUESDAY NIGHT. IN
THE SAME TIME FRAME THE ECMWF AND CANADIAN CONTINUE TO TRACK THE
SYSTEM MORE EASTERLY KEEPING ALL PRECIPITATION SOUTH OF OUR CWA. ON
A SIDE NOTE...THE LATEST GFS SOLUTION IS SLIGHTLY FARTHER SOUTH THAN
IT WAS FORECASTING 24 HOURS AGO. IF THIS TREND CONTINUES WE MAY BE
ABLE TO EVENTUALLY REMOVE CURRENT POPS.
FOR WHATEVER REASON THE SUPERBLEND STILL LEANS MORE TOWARD THE GFS
SOLUTION SO BASICALLY TOOK THE SUPERBLEND POPS AND TONED THEM DOWN A
BIT.
HIGH PRESSURE AT THE SURFACE SHOULD KEEP THE REGION DRY WITH THE
EXCEPTION OF TUESDAY AND TUESDAY NIGHT. TEMPERATURES THROUGH MOST OF
THE PERIOD WILL REMAIN BELOW NORMAL BUT RIDGING ALOFT SHOULD WARM
READINGS BACK TO NEAR NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 615 AM CDT FRI APR 24 2015
VFR CONDITIONS EXPECTED THROUGH 06Z ALTHOUGH ISOLATED SHOWERS AND
THUNDERSTORMS WILL MOVE ACROSS THE AREA FROM LATE THIS MORNING
INTO THE EVENING HOURS. EXPECT THE COVERAGE TO INCREASE WITH A
BETTER CHANCE OF OCCURRANCE OVER A TAF SITE AFTER 06Z. MFVR AND
POSSIBLY IFR CONDITIONS WITH SHOWERS AND THUNDERSTORMS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...PS
LONG TERM...JP
AVIATION...PS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1032 AM CDT FRI APR 24 2015
.DISCUSSION...
TWO AREAS OF CONCERN THIS MORNING ACROSS THE REGION...THE FIRST
BEING INCREASING COVERAGE OF THUNDERSTORMS ACROSS SOUTHEAST/EAST
CENTRAL TX AND THE SECOND BEING INCREASING COVERAGE NORTH OF THE
I-20 CORRIDOR.
THE FIRST IS DUE IN PART TO A WEAK PERTURBATION IN SW FLOW ALOFT
SWINGING NE FROM CENTRAL TX. THIS UPPER LEVEL FEATURE ALSO HAS
SOME SURFACE SUPPORT AS AN ANALYSIS SHOWS A WARM FRONT NEARLY
STAGNATED FROM N TX...SNAKING ITS WAY SOUTHEAST ACROSS THE LOWER
TOLEDO BEND RESERVOIR INTO SOUTHEAST LA. THIS WARM FRONT IS
EXPECTED TO COME SLOWLY NORTHWARD TODAY...PERHAPS AS FAR NORTH AS
THE I-20 CORRIDOR OF N LA. THE SECOND AREA OF CONCERN IS OF A MORE
ELEVATED NATURE THIS MORNING WITH COVERAGE NORTH OF THE I-20
CORRIDOR. THIS ACTIVITY IS WELL NORTH OF THE WARM FRONT BUT IS
SITUATED AGAIN WITH STRONGER PERTURBATIONS IN THE SOUTHWEST FLOW
ALOFT.
FOR THE UPDATE THIS MORNING...RAISED RAIN CHANCES WHERE THESE TWO
ENHANCED AREAS OF PRECIP WERE OBSERVED. OUR SEVERE WEATHER THREAT
FOR LATER TODAY/THIS EVENING WILL DEPEND GREATLY ON JUST HOW MUCH
WE ARE ABLE TO DESTABILIZE AND HOW FAR NORTH THE WARM FRONT MAKES
IT INTO OUR REGION FROM THE SOUTH. THE HRRR SHOWS A BREAK IN THE
WIDESPREAD ACTIVITY LATER THIS AFTN ACROSS THE SOUTHERN HALF OF NE
TX IN THE WAKE OF THE FIRST DISTURBANCE AND THIS MAY BE THE BREAK
NECESSARY FOR AT LEAST OUR SOUTHERN HALF TO WARM UP AS THIS AREA
SHOULD BE WELL INTO THE WARM SECTOR BY THIS TIME. DEEP LAYER SHEAR
IS SUPPORTIVE OF SUPERCELLS AND EVENTUAL BOWING LINE SEGMENTS IF
WE CAN GET THE INSTABILITY TO INCREASE LATER TODAY. LOW LEVEL
SHEAR WILL ALSO BE SUPPORTIVE OF A FEW TORNADOES...ESPECIALLY
ALONG AND JUST SOUTH OF THE WARM FRONT LATE THIS AFTERNOON/THIS
EVENING.
UPDATE OUT SHORTLY...13.
&&
.PREV DISCUSSION... /ISSUED 813 AM CDT FRI APR 24 2015/
AVIATION...
FOR THE 24/12Z TAFS...IFR/MVFR CIGS FOR MANY ATTM WITH WIDE
SPREAD SHWRS/TSTMS N ALONG I-30 AS A WARM FRONT IS RETURNING
NORTHWARD. EXPECT INTENSE CONVECTION DEVELOPING DURING THE
AFTERNOON IN OUR CWA FM W TO E AS A COLD FRONT SHIFTS EWRD ACROSS
TX/OK AT PEAK HEATING...DRIVING A SQ LINE(S) OF TSTMS DURING THE
EVENING HOURS. OUR ELY SFC WINDS WILL GRADUALLY BE VEERING TO
S/SELY THIS CYCLE. ALOFT...OUR CLIMB WINDS ARE ALREADY S/SE
5-25KTS TO 2KFT...THEN VEER TO ALL SW/W ALOFT 20-50KTS TO
20KFT...AND DUE WEST AT 75KTS BY FL240. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 75 70 89 64 / 80 80 20 0
MLU 74 71 90 64 / 70 80 30 10
DEQ 67 63 86 55 / 80 70 10 0
TXK 70 69 89 60 / 80 80 10 0
ELD 70 69 90 60 / 80 80 20 0
TYR 78 70 89 64 / 80 50 10 0
GGG 77 69 90 64 / 80 70 10 0
LFK 80 71 91 67 / 80 50 30 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24/13
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
606 AM CDT FRI APR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT FRI APR 24 2015
STRONG THETA-E ADVECTION IS ENSUING ACROSS THE AREA...WITH SKIES
MAINLY CLOUDY NOW ACROSS MN AS A RESULT. AS STRONG AS THIS FORCING
MAY BE...IT IS RUNNING INTO ONE HUGE PROBLEM...THE INCREDIBLY DRY
AIRMASS IN THE LOWER LEVELS IN PLACE ACROSS THE AREA EARLY THIS
MORNING. EVEN AT 3 AM THERE WERE SEVERAL LOCATIONS THAT STILL HAD
HUMIDITIES UNDER 25 PERCENT AND IN FACT...THERE ARE A FEW SITES OUT
IN WRN MN THAT ARE EVEN BORDERLINE RED FLAG CRITERIA WHERE SE WINDS
ARE STARTING TO GUST OUT OVER 20 MPH WITH HUMIDITIES UNDER 30
PERCENT. THE TRUE MAGNITUDE OF HOW DRY THIS AIRMASS IS COMES FROM
THE TWO SOUNDINGS RELEASED FROM MPX ON THURSDAY...BOTH OF WHICH
TALLIED PWATS UNDER A TENTH OF AN INCH. THIS IS COMMON WITH ARCTIC
OUTBREAKS IN THE DEAD OF WINTER...BUT IT IS EXCEEDINGLY RARE TO SEE
PWATS SO LOW AT THIS POINT IN APRIL.
WITHIN THIS WARM ADVECTION...THE MOISTURE CONVERGENCE AND
FRONTOGENESIS ARE REALLY CENTERED AROUND SE NODAK...WHERE RAIN IS
FINALLY STARTING TO MAKE INROADS TO THE SFC UP AROUND FARGO. FOR
THE REST OF TODAY...THEIR IS QUITE A BIT OF SPREAD AMONGST THE
SHORT TERM MODELS ON HOW THIS SYSTEM WILL SPREAD RAINFALL INTO
AREA...SO THERE IS LOW CONFIDENCE ON EXACT TIMING OF PRECIP AT ANY
ONE LOCATION. THIS IS LIKELY DUE TO THE LACK OF MUCH JET
SUPPORT...ALONG WITH NO REAL SHORT WAVE TO HELP FOCUS ACTIVITY.
INSTEAD...TODAY LOOKS TO BRING A GOOD 6-10 HOUR WINDOW TO MOST
LOCATIONS WHERE LIGHT RAIN WILL BE INTERMITTENT AS THE ZONE OF
THETA-E ADVECTION SWINGS THROUGH. DID CUT BACK SOME MORE ON QPF AS
WELL...WITH THIS LOOKING TO BE YET ANOTHER DISAPPOINTING SYSTEM IN
THE RAINFALL DEPARTMENT...WITH MOST FOLKS GETTING UNDER A TENTH OF
AN INCH OF RAIN. THE ONLY AREA THAT LOOKS LIKE THEY COULD DO
BETTER THAN THAT IS ACROSS CENTRAL MN...AS FRONTAL FORCING
CURRENTLY IN THE FARGO AREA PUSHES EAST THIS MORNING BEFORE
WEAKENING. FOR THE WEATHER GRIDS...MADE TWO CHANGES. ONE WAS TO
INTRODUCE ISOLATED THUNDER WORDING AS THE PLUME OF INSTABILITY
CURRENTLY UP INTO SE SODAK WILL PUSH INTO SW MN THIS
AFTERNOON...WITH THE NAM SHOWING A FEW HUNDRED J/KG OF MUCAPE
WORKING UP TO ABOUT A RED WING TO ALEXANDRIA LINE. ADDING FURTHER
SUPPORT TO BRINGING IN THE THUNDER MENTION WERE THE FACT THAT WE
HAVE SEEN INTERMITTENT LIGHTNING ACTIVITY ALL NIGHT WITH THE
SHOWERS WORKING ACROSS THE DAKOTAS...WITH THE SPC SREF
THUNDERSTORM PROBABILITIES GETTING UP ABOUT AS FAR NORTH AS I-94
AS WELL. THE SECOND CHANGE WAS TO REMOVE ANY MIXED PRECIP FROM THE
GRIDS THIS MORNING AS CLOUD COVER OVERNIGHT KEPT TEMPERATURES
HIGHER THAN WERE FORECAST...MEANING PRECIP MOVING IN WILL HAVE NO
PROBLEM MAINTAINING A LIQUID STATE.
TONIGHT WHAT LOOKS LIKE A CERTAINTY IS THE DEVELOPMENT OF LOW
STRATUS. AGAIN...THE FORCING FOR PRECIP DOES NOT LOOK ALL THAT GREAT
AS SFC ENERGY CONSOLIDATES INTO A SUB 1000 MB LOW THAT WILL BE
MOVING INTO THE KC AREA. THIS LOOKS TO KEEP THE BULK OF THE PRECIP
SOUTH OF THE MPX AREA...WITH THIS AREA LOOKING TO GET MORE LIGHT
RAIN/SPRINKLES TO GO ALONG WITH THE STRATUS. BASED ON WHAT WE SAW
WITH TEMPERATURES WITH THE CLOUDS TONIGHT...DID BOOST LOWS TONIGHT A
FEW DEGREES WITH THE CLOUDY SKIES EXPECTED. THIS RESULTED IN THE
BULK OF THE MIXED IN THE FORECAST FOR TONIGHT GETTING REMOVED AS
WELL.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 348 AM CDT FRI APR 24 2015
GOOD CONTINUITY CONTINUES BETWEEN THE GFS AND ECMWF FOR MUCH OF
THE LONG TERM...LEADING TO HIGHER CONFIDENCE WITH THE SENSIBLE
WEATHER. RAIN WILL DIMINISH FROM NORTH TO SOUTH ON SATURDAY AS A
WAVE OF LOW PRESSURE DROPS SOUTHEAST ACROSS THE MIDDLE MISSISSIPPI
VALLEY. LIKELY TO CATEGORICAL POPS CONTINUE IN FAR SOUTHERN MN
FOR THE MORNING WITH CHANCE POPS IN THE AFTERNOON. A RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE LOCAL AREA FOR SUNDAY AND MONDAY WITH
SOME FINE SPRING WEATHER OCCURRING. AFTER HIGHS IN THE LOWER 50S
ON SATURDAY...TEMPERATURES WILL WARM TO AROUND 60 FOR SUNDAY WITH
LOWER TO MIDDLE 60S FOR TUESDAY...WHICH IS ACTUALLY NORMAL FOR
LATE APRIL.
THERE REMAINS A SHORT WAVE AND WEAK COOL FRONT THAT WILL PUSH
ACROSS THE FORECAST AREA FROM MONDAY NIGHT THROUGH TUESDAY NIGHT.
THIS SYSTEM IS WEAKENING WITH TIME WITH ONLY SMALL POPS INDICATED
TO THE WEST AND NORTH OF THE TWIN CITIES FOR MONDAY NIGHT AND
TUESDAY. A MUCH LARGER RIDGE OF HIGH PRESSURE WILL FOLLOW AND EXPAND
OUT ACROSS THE NORTHERN ROCKIES AND PLAINS FOR WEDNESDAY AND
THURSDAY. DRY WEATHER IS IN STORE FOR THE REGION WITH HIGH
TEMPERATURES TRENDING ABOVE NORMAL WITH UPPER 60S TO LOWER 70S
LIKELY. EVEN WARMER TEMPERATURES ARE POSSIBLE FOR THE END OF THE
WEEK (FRIDAY AND SATURDAY) AS RIDGING ALOFT DOMINATES THE CENTRAL
THIRD OF THE CONUS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 606 AM CDT FRI APR 24 2015
LLJ WORKING INTO WRN MN THIS MORNING HAS SHOWERS WITH EMBEDDED
TSTRMS FROM OMAHA TO FARGO. HOWEVER...WE ARE STILL DEALING WITH A
VERY DRY AIRMASS IN THE LOW LEVELS WHICH IS MAKING EWRD PROGRESS
INTO THE MPX AREA DIFFICULT. FELT TIMING FROM INHERITED TAFS
LOOKED GOOD BASED ON LATEST HRRR/HOPWRF FORECASTS SO MADE MINIMAL
CHANGES THERE. GIVEN THE DRY AIR...ALSO FAVORED THE SLOWER SREF
FOR BRINGING MVFR AND LOWER CIGS INTO THE AREA. IN FACT...SREF CIG
PROBABILITIES PAINT THE POSSIBILITY THAT DRY ERLY FLOW WILL KEEP
THE WI TERMINALS VFR THROUGH THIS TAF PERIOD. AT THE VERY
LEAST...LOWEST CLOUDS LOOK TO BE OUT IN WRN MN TONIGHT...WITH IFR
OR LOWER CIGS LIKELY WEST OF I-35.
KMSP...UNCERTAINTY EXISTS ON TWO FRONT FOR THIS TAF...TIMING ON
WHEN OR EVEN IF MSP SEES RAIN ALONG WITH HOW LOW DO CIGS GO. FOR
THE RAIN...ONE BAND OF VIRGA ALREADY MOVED THROUGH THIS
MORNING...BUT MAIN BATCH OF FORCING LOOKS TO ARRIVE CLOSER TO 18Z.
FOR MUCH OF THE AFTERNOON...EXPECT INTERMITTENT PERIODS OF -RA
THAT MAY CONTINUE INTO MUCH OF TONIGHT. HRRR AND LAMP WOULD SAY
MVFR CIGS MOVE IN WITH THE RAIN CHANCES...BUT GIVEN HOW DRY WE ARE
IN THE LOW LEVELS...FAVORED THE SLOWER TIMING OF THE SREF.
CONFIDENCE ON CIGS GOING BELOW 018 TONIGHT IS MEDIUM AS LOWER
CIGS AND BETTER MOISTURE LOOK TO REMAIN OFF TO THE WEST...WITH
CONTINUED DRY ERLY SFC WINDS PLAYING HAVOC ON CLOUD HEIGHTS
THROUGH TONIGHT.
/OUTLOOK FOR KMSP/
SAT...BCMG VFR. WINDS E 10-15 KT.
SUN...VFR. WINDS NE 5-10 KT.
MON...VFR. WINDS NNE 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...RAH
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1046 AM EDT FRI APR 24 2015
.SYNOPSIS...
A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE
ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW
WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE
HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW
NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1046 AM EDT FRIDAY...HAVE LOWERED MAX TEMPERATURES FOR
TODAY SEVERAL DEGREES FROM THE PREVIOUS FORECAST...BASED ON
CURRENT SURFACE OBSERVATIONS...THE LATEST GFS LAMP GUIDANCE AND
THE 06Z GFS MOS GUIDANCE. FORECAST AREA REMAINS UNDER CYCLONIC
FLOW FROM A SURFACE LOW PRESSURE AREA AND AN UPPER LOW OVER THE
CANADIAN MARITIMES. WILL CONTINUE TO KEEP IN LOW CHANCE POPS FOR
RAIN OR SNOW SHOWERS TODAY...WITH SNOW SHOWERS MAINLY OVER THE
HIGHER ELEVATIONS DURING THE DAY TODAY.
PREVIOUS DISCUSSION FROM 638 AM EDT FRIDAY...JUST A ROUTINE
LITTLE REFRESH TO INJECT CURRENT OBSERVATION/RADAR TRENDS INTO THE
FIRST FEW HOURS OF THE FORECAST. A FEW SNOW SHOWERS HAVE AGAIN
BLOSSOMED ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST
EAST OF BURLINGTON. 06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL
MARGINALLY BLOCKED WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS
PROBABLY CONTRIBUTING TO THE FORMATION OF THESE FLURRIES/SNOW
SHOWERS. FLOW GOES UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE
09Z HRRR DEPICTION OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT
ADJUSTMENTS TO THE POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE.
THUS, THE CURRENT FLURRIES/SNOW SHOWERS SHOULD COME TO AN END
SHORTLY, THEN A BREAK, THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS
AFTERNOON ACROSS THE HIGHER TERRAIN.
WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING...
SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR.
RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE
AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD
TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS
RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER
ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS
ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING
OVER THE NEXT 6 HOURS OR SO.
A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA
BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW
PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH
NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE
BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT
THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO
SEE A FEW GUSTS OVER 25 MPH.
OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT
ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY
CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER,
GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD
WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN
THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS.
WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF
DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO
DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN
NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW.
IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200
FEET. ACCUMULATIONS WILL BE VERY MINOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL,
PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER
LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO
TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET
RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED
CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF
THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO
SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW.
INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL
AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO
PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES
OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT
EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF
SNOW.
SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM
THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE
TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT
INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY.
STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION
EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW
STILL DEPENDING ON ELEVATION).
TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH
DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN
SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE,
SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND
OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL
INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING
EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY
LATE NEXT WEEK.
THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST
CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY
NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER
ELEVATIONS AT NIGHT.
SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW
PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT
POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK.
TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON
THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT
WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER
ELEVATIONS.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
THROUGH 12Z SATURDAY...PRIMARILY VFR THROUGH 00Z SATURDAY UNDER A
BKN-OVC SKY. SOME INSTABILITY/WRAPAROUND SHOWERS MAY RETURN...MAINLY
ACROSS MOUNTAINS AFT 21Z FRI AND BECOME MORE WIDESPREAD AFT 00Z
SAT...AFT 00Z POSSIBLE MVFR AT KSLK/KMPV. SURFACE WINDS WNW
10-15 KNOTS WITH SOME GUSTS UP TO 20 KNOTS.
OUTLOOK 12Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD -
VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED
RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...WGH/NASH
SHORT TERM...NASH
LONG TERM...SLW
AVIATION...SLW
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
737 AM EDT FRI APR 24 2015
.SYNOPSIS...
A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE
ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW
WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE
HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW
NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 638 AM EDT FRIDAY...JUST A ROUTINE LITTLE REFRESH TO INJECT
CURRENT OBSERVATION/RADAR TRENDS INTO THE FIRST FEW HOURS OF THE
FORECAST. A FEW SNOW SHOWERS HAVE AGAIN BLOSSOMED ALONG THE
WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST EAST OF BURLINGTON.
06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL MARGINALLY BLOCKED
WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS PROBABLY CONTRIBUTING
TO THE FORMATION OF THESE FLURRIES/SNOW SHOWERS. FLOW GOES
UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE 09Z HRRR DEPICTION
OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT ADJUSTMENTS TO THE
POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE. THUS, THE CURRENT
FLURRIES/SNOW SHOWERS SHOULD COME TO AN END SHORTLY, THEN A BREAK,
THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS AFTERNOON ACROSS THE
HIGHER TERRAIN.
WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING...
SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR.
RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE
AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD
TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS
RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER
ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS
ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING
OVER THE NEXT 6 HOURS OR SO.
A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA
BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW
PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH
NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE
BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT
THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO
SEE A FEW GUSTS OVER 25 MPH.
OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT
ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY
CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER,
GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD
WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN
THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS.
WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF
DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO
DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN
NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW.
IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200
FEET. ACCUMULATIONS WILL BE VERY MINOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL,
PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER
LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO
TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET
RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED
CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF
THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO
SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW.
INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL
AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO
PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES
OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT
EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF
SNOW.
SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM
THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE
TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT
INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY.
STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION
EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW
STILL DEPENDING ON ELEVATION).
TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH
DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN
SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE,
SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND
OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL
INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING
EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY
LATE NEXT WEEK.
THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST
CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY
NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER
ELEVATIONS AT NIGHT.
SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW
PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT
POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK.
TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON
THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT
WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER
ELEVATIONS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THROUGH 12Z SATURDAY...PRIMARILY VFR THROUGH 00Z SATURDAY UNDER A
BKN-OVC SKY. SOME INSTABILITY/WRAPAROUND SHOWERS MAY RETURN...MAINLY
ACROSS MOUNTAINS AFT 21Z FRI AND BECOME MORE WIDESPREAD AFT 00Z
SAT...AFT 00Z POSSIBLE MVFR AT KSLK/KMPV. SURFACE WINDS WNW
10-15 KNOTS WITH SOME GUSTS UP TO 20 KNOTS.
OUTLOOK 12Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD -
VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED
RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT.
&&
.HYDROLOGY...
UPDATED 1102 PM THURSDAY...THE FLOOD WARNING CONTINUES FOR THE
BARTON RIVER NEAR COVENTRY. THE RIVER WENT ABOVE FLOOD STAGE EARLY
THIS MORNING AND WENT UP QUICKLY...CRESTING AROUND 8.8 FEET THIS
AFTERNOON. SINCE THEN...THE WATER LEVEL OF THE RIVER HAS BEGUN TO
FALL...AND AT 11 PM IT WAS AT 8.4 FEET. EXPECT THIS TREND TO
CONTINUE OVERNIGHT. CURRENTLY THE BARTON RIVER NEAR COVENTRY IS
THE ONLY RIVER THAT WE EXPECT TO REACH FLOOD STAGE AS MOST OF THE
OTHER RIVERS AND STREAMS HAVE CRESTED BELOW FLOOD STAGE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...NASH
SHORT TERM...NASH
LONG TERM...SLW
AVIATION...SLW
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
646 AM EDT FRI APR 24 2015
.SYNOPSIS...
A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE
ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW
WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE
HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW
NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 638 AM EDT FRIDAY...JUST A ROUTINE LITTLE REFRESH TO INJECT
CURRENT OBSERVATION/RADAR TRENDS INTO THE FIRST FEW HOURS OF THE
FORECAST. A FEW SNOW SHOWERS HAVE AGAIN BLOSSOMED ALONG THE
WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST EAST OF BURLINGTON.
06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL MARGINALLY BLOCKED
WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS PROBABLY CONTRIBUTING
TO THE FORMATION OF THESE FLURRIES/SNOW SHOWERS. FLOW GOES
UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE 09Z HRRR DEPICTION
OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT ADJUSTMENTS TO THE
POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE. THUS, THE CURRENT
FLURRIES/SNOW SHOWERS SHOULD COME TO AN END SHORTLY, THEN A BREAK,
THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS AFTERNOON ACROSS THE
HIGHER TERRAIN.
WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING...
SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR.
RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE
AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD
TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS
RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER
ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS
ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING
OVER THE NEXT 6 HOURS OR SO.
A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA
BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW
PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH
NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE
BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT
THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO
SEE A FEW GUSTS OVER 25 MPH.
OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT
ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY
CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER,
GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD
WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN
THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS.
WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF
DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO
DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN
NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW.
IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200
FEET. ACCUMULATIONS WILL BE VERY MINOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL,
PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER
LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO
TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET
RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED
CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF
THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO
SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW.
INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL
AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO
PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES
OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT
EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF
SNOW.
SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM
THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE
TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT
INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY.
STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION
EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW
STILL DEPENDING ON ELEVATION).
TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH
DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN
SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE,
SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND
OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL
INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING
EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY
LATE NEXT WEEK.
THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST
CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY
NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER
ELEVATIONS AT NIGHT.
SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW
PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT
POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK.
TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON
THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT
WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER
ELEVATIONS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THROUGH 06Z SATURDAY...A VARIETY OF FLIGHT CATEGORIES IS EXPECTED
OVERNIGHT WILL GRADUALLY IMPROVE TO VFR CONDITIONS FOR LATER
FRIDAY MORNING AND AFTERNOON. WEST/NORTHWESTERLY HAS LEAD TO
TERRAIN-DRIVEN RAIN AND SNOW SHOWERS...ESPECIALLY SLK/MPV AND
WESTERN SLOPES JUST E OF BTV BUT ACTIVITY SHOULD DECREASE BY
MORNING. NOT MUCH IMPACT EXPECTED AT BTV/PBG/MSS EXCEPT FOR A
POSSIBLE LIGHT SHOWER...WITH VFR IN THE FORECAST. MPV/SLK WILL SEE
PERIODS OF SNOW SHOWERS...WITH MVFR/IFR LIKELY. RUT EXPECTED TO
SEE SOME LOWER CEILINGS (MVFR) AND A FEW SHOWERS NEARBY. LOWER
CEILINGS/SHOWERS GRADUALLY DISSIPATE AND LIFT ON FRIDAY WITH ALL
SITES VFR BY 16Z. SOME INSTABILITY SHOWERS MAY RETURN...MAINLY
ACROSS MOUNTAINS AFT 21Z FRI. SURFACE WINDS GENERALLY ANTICIPATED
TO BE OUT OF THE WEST FROM 5-15 KNOTS...WITH SOME GUSTS UP TO 20
KNOTS...MAINLY ON FRIDAY.
OUTLOOK 06Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD -
VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED
RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT.
&&
.HYDROLOGY...
UPDATED 1102 PM THURSDAY...THE FLOOD WARNING CONTINUES FOR THE
BARTON RIVER NEAR COVENTRY. THE RIVER WENT ABOVE FLOOD STAGE EARLY
THIS MORNING AND WENT UP QUICKLY...CRESTING AROUND 8.8 FEET THIS
AFTERNOON. SINCE THEN...THE WATER LEVEL OF THE RIVER HAS BEGUN TO
FALL...AND AT 11 PM IT WAS AT 8.4 FEET. EXPECT THIS TREND TO
CONTINUE OVERNIGHT. CURRENTLY THE BARTON RIVER NEAR COVENTRY IS
THE ONLY RIVER THAT WE EXPECT TO REACH FLOOD STAGE AS MOST OF THE
OTHER RIVERS AND STREAMS HAVE CRESTED BELOW FLOOD STAGE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...NASH
SHORT TERM...NASH
LONG TERM...SLW
AVIATION...MUCCILLI/SLW
HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
648 AM CDT FRI APR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT FRI APR 24 2015
NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION
CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS
IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET
FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA.
MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE
WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS
BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO
SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH
RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR
THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH...
BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR
FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF
THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK
RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH
AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF
HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA.
AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN
THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE
WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE
OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE
SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL
MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND
LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT
IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES
REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER
MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT
ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE
THIS AFTERNOON/EVENING.
FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES
SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT
STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS
HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS
EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER
NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD
ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED
TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST
IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST
MINNESOTA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 415 AM CDT FRI APR 24 2015
ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM
NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS
NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS
AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH
EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW
NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH
DAKOTA.
MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY
FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW
POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL
CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY
IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG
ENOUGH FOR RED FLAG.
MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH
WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME
SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE.
CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE
LIMITED.
LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET
BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO
INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE
WEATHER CONCERNS LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 648 AM CDT FRI APR 24 2015
AREAS OF MVFR CEILINGS NEAR/EAST OF I-29 CORRIDOR AT THE START OF
THE PERIOD EXPECTED TO BECOME MORE WIDESPREAD THROUGH THE DAY AS
INCREASING LOW LEVEL MOISTURE SPREADS INTO THE REGION. SHOWERS AND
ISOLATED THUNDERSTORMS WILL ALSO ACCOMPANY THE INCREASING MOISTURE
ACROSS THE AREA TODAY THROUGH TONIGHT. BOTH THE LOW CEILINGS AND
GREATER CHANCE OF PRECIPITATION WILL BE MORE PROMINENT EAST OF THE
JAMES RIVER VALLEY...WITH THE KHON TAF SITE LARGELY EXPECTED TO
REMAIN VFR UNTIL AFTER 03Z THIS EVENING WHEN A MORE EASTERLY LOW
LEVEL FLOW WILL PULL THE MVFR CEILINGS WESTWARD INTO THE JAMES
VALLEY.
GIVEN UNCERTAINTY REGARDING TIMING/LOCATION OF THUNDER CHANCES...
OPTED TO LEAVE OUT OF THE TAFS AT THIS TIME. HOWEVER...POTENTIAL
CANNOT BE RULED OUT GIVEN MID LEVEL INSTABILITY. KHON MAY ACTUALLY
SEE A GREATER THUNDER THREAT THAN KFSD/KSUX...AS INSTABILITY MAY
BECOME SURFACE BASED THERE IN THE LATE AFTERNOON/EVENING. HOWEVER
THIS THREAT CONDITIONAL ON WHETHER PRECIPITATION ACTUALLY DEVELOPS
IN THAT FAR NORTH...SO AGAIN WILL KEEP THE TAF DRY FOR NOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...
AVIATION...JH
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
948 AM CDT FRI APR 24 2015
.DISCUSSION...
LEADING IMPULSE SUPPORTING AREA OF ELEVATED MOIST CONVECTION OVER
THE NRN COUNTIES WILL CONTINUE TO QUICKLY PULL NEWD THROUGH THE
DAY...AND PULL RAIN OUT OF THE AREA BY EARLY AFTERNOON. MODEST
DIURNAL HEATING HAS ALLOWED AIRMASS TO BECOME MODERATELY UNSTABLE
FEEDING INTO THIS COMPLEX AS OF 14Z. HOWEVER...CAPPING REMAINS IN
PLACE. WITH FURTHER DIURNAL HEATING...A FEW CELLS MAY STRENGTHEN
WITH PRIMARY THREATS OF BRIEF HEAVY RAIN AND SOME HAIL. WILL
CONTINUE TO MONITOR RADAR TRENDS FOR THESE CELLS...ALTHOUGH
CURRENT THINKING IS SVR THREAT WILL REMAIN MODEST AT BEST WITH
ONGOING STORMS THROUGH THE REST OF THE MORNING WITH BRIEF HEAVY
RAINFALL.
MUCH OF THE AREA WILL ESSENTIALLY REMAIN BETWEEN SYSTEMS
TODAY...WITH LOWER POPS THIS AFTERNOON. 12Z UA ANALYSIS/SOUNDINGS
INDICATE RICH SURFACE MOISTURE FEED IS QUITE SHALLOW...WHICH WILL
LIKELY KEEP RAIN CHANCES IN THE SCATTERED RANGE AT BEST FOR THE
REST OF THE AFTERNOON AS AFTERNOON HEATING FURTHER WEAKENS CAP.
OTHER THAN MAKING NEAR TERM CHANGES ASSOCIATED WITH ONGOING
WEATHER...HAVE LEFT REST OF FORECAST THE SAME.
48
&&
.PREV DISCUSSION... /ISSUED 705 AM CDT FRI APR 24 2015/
AVIATION...
THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY.
LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO
DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY.
THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHING
KCLLAT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS
ACROSS KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL
LIKELY OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW
OF HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z.
THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER
CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP
LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE
SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A
MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE
MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE
CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING
MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT
FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 84 70 88 68 88 / 90 50 20 10 20
HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20
GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...48
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
705 AM CDT FRI APR 24 2015
.UPDATE...
SENT AN UPDATE FOR THE MARINE WINDS FOR THIS MORNING. THE REMNANTS
OF THE MESOSCALE CONVECTIVE COMPLEX THAT AFFECTING DEEP SOUTH
TEXAS EARLIER THIS MORNING SHOULD MOVE UP THE COAST THIS MORNING.
THESE MAY GENERATE ISOLATED SHOWERS AND THUNDERSTORMS AND GUSTY
WINDS.
40
&&
.PREV DISCUSSION... /ISSUED 632 AM CDT FRI APR 24 2015/
DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
AVIATION...
THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY.
LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO
DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY.
THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHING
KCLLAT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS
ACROSS KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL
LIKELY OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW
OF HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z.
THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER
CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP
LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE
SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A
MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE
MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE
CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING
MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT
FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY.
40
PREV DISCUSSION... /ISSUED 547 AM CDT FRI APR 24 2015/
UPDATE...
RAISING POPS PER RADAR TRENDS.
DISCUSSION...
WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A
WEAK 850 MB BOUNDARY. CONVECTION IS BACK BUILDING TO THE E-SE IN
LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43
PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/
DISCUSSION...
AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO
TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR
SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD
SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING
BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A
FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER
WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES
IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT
SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN
OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT.
MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED
2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C
AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850
MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO
EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700
MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST.
AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE
TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK
RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF.
MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE
CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE
WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY
WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z.
THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST
DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND
FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000
AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS
INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF
SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN
OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO
TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE
850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT
NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE
COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN
LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO
MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE
STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE
ENTIRE AREA.
PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY
SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL
EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH
A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH
A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL
LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20
POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL
APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND
OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD
AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES
MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF
THE FRONT. 43
MARINE...
ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT
CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT
INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY
TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL
PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY
AFTERNOON AND PERSIST INTO TUESDAY NIGHT.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20
HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20
GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
632 AM CDT FRI APR 24 2015
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY.
LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO
DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY.
THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHINGKCLL
AT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS ACROSS
KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL LIKELY
OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW OF
HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z.
THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER
CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP
LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE
SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A
MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE
MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE
CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING
MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT
FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY.
40
&&
.PREV DISCUSSION... /ISSUED 547 AM CDT FRI APR 24 2015/
UPDATE...
RAISING POPS PER RADAR TRENDS.
DISCUSSION...
WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A
WEAK 850 MB BOUNDARY. CONVECTION IS BACKBUILDING TO THE E-SE IN
LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43
PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/
DISCUSSION...
AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO
TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR
SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD
SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING
BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A
FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER
WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES
IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT
SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN
OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT.
MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED
2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C
AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850
MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO
EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700
MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST.
AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE
TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK
RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF.
MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE
CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE
WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY
WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z.
THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST
DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND
FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000
AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS
INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF
SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN
OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO
TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE
850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT
NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE
COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN
LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO
MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE
STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE
ENTIRE AREA.
PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY
SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL
EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH
A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH
A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL
LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20
POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL
APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND
OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD
AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES
MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF
THE FRONT. 43
MARINE...
ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT
CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT
INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY
TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL
PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY
AFTERNOON AND PERSIST INTO TUESDAY NIGHT.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20
HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20
GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
547 AM CDT FRI APR 24 2015
.UPDATE...
RAISING POPS PER RADAR TRENDS.
&&
.DISCUSSION...
WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A
WEAK 850 MB BOUNDARY. CONVECTION IS BACKBUILDING TO THE E-SE IN
LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43
&&
.PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/
DISCUSSION...
AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO
TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR
SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD
SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING
BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A
FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER
WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES
IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT
SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN
OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT.
MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED
2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C
AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850
MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO
EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700
MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST.
AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE
TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK
RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF.
MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE
CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE
WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY
WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z.
THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST
DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND
FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000
AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS
INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF
SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN
OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO
TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE
850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT
NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE
COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN
LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO
MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE
STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE
ENTIRE AREA.
PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY
SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL
EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH
A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH
A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL
LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20
POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL
APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND
OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD
AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES
MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF
THE FRONT. 43
MARINE...
ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT
CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT
INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY
TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL
PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY
AFTERNOON AND PERSIST INTO TUESDAY NIGHT.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20
HOUSTON (IAH) 84 72 88 70 88 / 40 40 50 10 20
GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1000 AM MST FRI APR 24 2015
.SYNOPSIS...
A SERIES OF PACIFIC WEATHER DISTURBANCES WILL SLOWLY
MOVE THROUGH THE REGION TODAY AND THIS WEEKEND...PROVIDING COOLER
TEMPERATURES AND MORE HUMID CONDITIONS. A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS IS FORECAST OVER THE SOUTH CENTRAL ARIZONA
MOUNTAINS TODAY...WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS
SATURDAY NIGHT IN SOUTHWEST AND SOUTH CENTRAL ARIZONA. A STRONG COLD
FRONT IS FORECAST TO MOVE INTO CENTRAL ARIZONA SATURDAY NIGHT.
CLEARING SKIES ARE EXPECTED BY LATER SUNDAY WITH DRY AND MUCH
WARMER WEATHER NEXT WEEK.
&&
.DISCUSSION...
UPPER TROUGH AXIS IS OVER ARIZONA THIS MORNING EXTENDING
SOUTHWESTWARD ACROSS NORTHERN BAJA MEXICO. THE MAIN VORT MAX WITHIN
THE TROUGH IS ALREADY OVER NEW MEXICO. A WEAKER TRAILING VORT MAX
HAS BEEN HELPING TO PRODUCE ISOLATED TO SCATTERED SHOWERS OVER
MARICOPA...PINAL...AND GILA COUNTIES. CAPE LOOKS QUITE MODEST BUT
JUST ENOUGH TO GET SOME STRAY SHOWERS THAT HAVE HEAVIER SHOWERS WITH
THEM THAN THE OTHERS. COULD POSSIBLY GET A DEEP ENOUGH SHOWER TO GET
A RUMBLE OF THUNDER. EVEN IN THAT SCENARIO...NOT LOOKING AT ANY
FLOODING ISSUES AS IT WOULD BE VERY LOCALIZED AND BRIEF. HRRR KEEPS
ISOLATED SHOWER ACTIVITY GOING INTO THE AFTERNOON WHILE OTHER HI RES
MODELS TREND THINGS DOWN QUICKLY AFTER MIDDAY. WILL MAKE SOME MINOR
ADJUSTMENTS TO KEEP POPS GOING PAST 18Z TODAY. NEXT SYSTEM BEGINS
ENTERING OUR FORECAST AREA SATURDAY AFTERNOON WITH THE MAIN
DYNAMICAL PUSH HAPPENING BETWEEN 00Z-18Z SUNDAY. MORE LATER.
&&
.PREVIOUS DISCUSSION ISSUED 305 AM MST/PDT...
TODAY...
A BROAD COOL LOW PRESSURE SYSTEM WAS SLOWLY MOVING THROUGH
CENTRAL ARIZONA EARLY THIS MORNING FROM THE WEST. 00Z PLOT DATA...
5PM LAST EVENING DETECTED A CONSIDERABLE AMOUNT OF BOUNDARY LAYER
MOISTURE 7000 FEET DEEP SPREADING ACROSS THE COLORADO RIVER FROM
SOUTHERN CA. THIS IS A SIGNIFICANT AMOUNT OF MOISTURE RELATIVE TO
TEMPS ALOFT...AND WILL SPREAD EAST ACROSS AZ TODAY.
AS THE UPPER LOW SLOWLY MOVED INTO AZ OVERNIGHT...SHOWERS AND
THUNDERSTORMS WERE NOTED IN FAR SOUTHEAST AZ JUST BEFORE MIDNIGHT...
WITH ISOLATED SHOWERS AND THUNDERSTORMS IN MARICOPA COUNTY JUST
NORTH OF PHOENIX AT 2 AM. CURRENT FORECASTS HANG ON TO A SLIGHT
CHANCE OF SHOWERS THROUGH THE FRIDAY MORNING HOURS...WITH THE SHOWER
THREAT ENDING IN ALL BUT SOUTHERN GILA COUNTY ZONE 24 BY EARLY
AFTERNOON.
TONIGHT AND SATURDAY...
ALTHOUGH CONSIDERABLE BOUNDARY LAYER MOISTURE WILL RESIDE OVER THE
FORECAST AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ...THE ATMOSPHERE
WILL BE TOO STABLE TO GENERATE ANY SHOWER ACTIVITY. THEREFORE PARTLY
CLOUDY SKIES WITH BELOW NORMAL TEMPERATURES ARE FORECAST AREA-WIDE.
SATURDAY NIGHT AND SUNDAY...
A POWERFUL NEGATIVE TILT TROF IS STILL FORECAST TO RAPIDLY DEEPEN
INTO CENTRAL AZ SATURDAY NIGHT. IN FACT... THE STRONGEST VERTICAL
MOTION FIELD...REPLETE WITH POSSIBLE HEAVY SHOWERS AND THUNDERSTORMS
WILL BECOME FOCUSED BETWEEN PRESCOTT AND QUARTZSITE BY 9 PM
SATURDAY...OR IN LA PAZ AND NORTHWEST MARICOPA COUNTIES...THEN
SPREAD EAST ACROSS THE PHOENIX AREA BY 2 AM SATURDAY NIGHT. SINCE
BOUNDARY LAYER MOISTURE WILL BE RELATIVELY DEEP...THIS CLASSIC FAST
MOVING COLD FRONT MAY RESULT IN A LINE OF SHWRS/TSTMS WITH POTENTIAL
FOR BRIEF HEAVY RAIN AND STRONG WIND. PORTIONS OF SOUTHEAST CA IN
RIVERSIDE COUNTY MAY SEE A FEW SHOWERS/SLIGHT CHANCE OF
THUNDERSTORMS EARLY SATURDAY EVENING...BUT MOST OF THE ACTIVITY WILL
BE CONFINED TO ARIZONA.
THE COLD FRONT BY 7 AM SUNDAY SHOULD HAVE MOVED TO THE EASTERN AZ
BORDER RESULTING IN LINGERING SHOWERS OR UNSETTLED CONDITIONS OVER
SOUTH CENTRAL ARIZONA SUNDAY AFTERNOON...MAINLY PHOENIX EASTWARD.
CLEARING SUNDAY NIGHT.
MONDAY THROUGH THURSDAY...
DRY NORTHERLY FLOW WILL DEVELOP MONDAY AND TUESDAY FOLLOWED BY A
BUILDING RIDGE OVER THE REGION WEDNESDAY AND THURSDAY. MUCH WARMER
TEMPERATURES ARE FORECAST WEDNESDAY WITH NEAR 100 DEGREE HEAT ON THE
WARMEST DESERTS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SCATTERED SHOWERS CONTINUE ACROSS THE AREA THIS MORNING AND WILL
PERSIST INTO THE EARLY AFTERNOON HOURS. KIWA/KSDL THE MOST LIKELY TO
SEE SHOWERS AT THE AIRFIELD WHILE KPHX MAY ONLY SEE VCSH BASED ON
RADAR TRENDS. WIDESPREAD CIGS AROUND 6KFT WILL BE COMMON THROUGH LATE
AFTERNOON. OTHERWISE EXPECT CONDITIONS TO IMPROVE LATE THIS
AFTERNOON/EVENING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
FEW-SCT HIGH CLOUDS FROM FRIDAY MORNING ONWARD. PASSING UPPER LEVEL
TROUGH WILL CONTINUE ELEVATED WINDS...WITH GUSTS INTO TO 20KT RANGE
PSBL THROUGHOUT THE DAY. STRONGER WINDS IN THE FORECAST FOR
SATURDAY...WITH GUSTS PUSHING 35KTS PARTICULARLY ACROSS IMPERIAL
COUNTY AND KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
FINAL PIECE OF A POTENT UPPER LEVEL TROUGH WILL SWIFTLY MOVE THROUGH
THE REGION SUNDAY...SUPPORTING ADDITIONAL BREEZY TO LOCALLY WINDY
CONDITIONS. DEWPOINTS WILL SLOWLY DRY IN THE WAKE OF A PASSING COOL
FRONT...BUT CRITICALLY LOW HUMIDITIES WILL GENERALLY BE OFFSET OF
THE STRONGEST WINDS AND EVEN THEN ONLY DRY INTO THE 20 PERCENT RANGE
OR SO ON SUNDAY. THE MAIN TROUGH FEATURE WILL CLEAR THE AREA SUNDAY
NIGHT/MONDAY...WITH RESIDUAL WEAK TROUGH HEIGHTS LINGERING OVER THE
SOUTHWEST. DRY AIR WILL CONTINUE TO SETTLE INTO THE REGION WHILE
TEMPERATURES WARM TO MORE SEASONAL...AND EVEN ABOVE
SEASONAL...READINGS. THIS WILL RESULT IN SINGLE DIGIT AFTERNOON
HUMIDITIES WITH FAIR OVERNIGHT RECOVERIES. WINDS FROM MONDAY ONWARD
WILL GENERALLY BE LIGHT AND WILL FOLLOW TYPICAL DIURNAL TRENDS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...WIND ADVISORY FROM 1 PM TO 9 PM PDT SATURDAY FOR CAZ030>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...VASQUEZ
AVIATION...LEINS
FIRE WEATHER...NOLTE/LEINS
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
400 PM EDT FRI APR 24 2015
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS DEEP TROUGHING THROUGH
THE DESERT SOUTHWEST INTO NORTHERN MEXICO...FOLLOWED DOWNSTREAM BY
AMPLIFIED RIDGING ACROSS THE GULF OF MEXICO AND DEEP SOUTH STATES.
MOIST SUBTROPICAL JET IS RIDING NORTHWARD BETWEEN THESE TWO
FEATURES OVER THE SOUTHERN PLAINS BEFORE TURNING EASTWARD ACROSS
THE SOUTHEAST CONUS. THE FLORIDA PENINSULA RESIDES ON THE EASTERN
PERIPHERY OF THE UPPER RIDGE WHERE OUR DEEP LAYER WINDS PER 12Z
KTBW SOUNDING PROFILE WERE FROM THE NORTHWEST. SOUNDING DID SHOW A
BIT OF A SUBSIDENCE INVERSION ASSOCIATED WITH THE UPPER RIDGE
AROUND 700MB...WITH A MOIST PROFILE BELOW THIS LEVEL TO THE
SURFACE.
AT THE SURFACE...
1020MB CONTINENTAL HIGH PRESSURE RIDGING DOWN INTO THE SOUTHEAST
CONUS HAS PUSHED A WEAK FRONTAL BOUNDARY DOWN INTO THE CENTRAL
FLORIDA PENINSULA. CONTINUE TO SEE A BIG GRADIENT IN SURFACE
DEWPOINTS ACROSS THIS BOUNDARY WITH LOWER 70S SOUTH OF THE I-4
CORRIDOR...AND THEN QUICKLY DROPPING TO READINGS IN THE 50S AROUND
OCALA. THE GENERAL LOCATION OF THE BOUNDARY CAN ALSO BE EASILY
SEEN WITH VISIBLE SATELLITE IMAGERY...WHERE A DEFINED CUMULUS
DEVELOPMENT CUTOFF IS LOCATED VERY NEAR I-4. SOUTH OF THIS
LINE...DIURNAL HEATING WORKED WITH THE GREATER BOUNDARY LAYER
MOISTURE TO FORM THE SCT-BKN CUMULUS FIELD...WHILE NORTH THE
MOISTURE IS SIMPLY NOT IN PLACE TO EFFICIENTLY PRODUCE MUCH IN THE
WAY OF CLOUDS.
REGIONAL RADARS SHOW A FEW SHOWERS TRYING TO DEVELOP ALONG THE SEA
BREEZE JUST EAST OF FORT MYERS DOWN TOWARD AREAS JUST EAST OF
NAPLES. LAST FEW HRRR RUNS SUGGEST WE WILL SEE SOME ADDITIONAL
DEVELOPMENT UP INTO OUR SOUTH-CENTRAL ZONES INTO THE EARLY EVENING
AS THE SEA-BREEZE CONTINUES TO ATTEMPT MIGRATING INLAND...HOWEVER
ONLY EXPECTING ISOLATED TO WIDELY SCT COVERAGE.
&&
.SHORT TERM (REST OF TODAY THROUGH SATURDAY...
REST OF TODAY...
THE FORECAST WILL BE SPLIT NORTH TO SOUTH BY THE BOUNDARY NEAR THE
I-4 CORRIDOR. NORTH OF THIS BOUNDARY...THE LACK OF BL MOISTURE
MAKES INSTABILITY REALLY LACKING AND DO NOT HAVE ANY THUNDERSTORM
MENTION IN THE FORECAST. AS MENTIONED ABOVE IN THE SYNOPSIS...SOUTH
OF THE I-4 CORRIDOR...THE SEA- BREEZE SHOULD PROVIDE JUST ENOUGH
FOCUS...AND THE COLUMN IS JUST CONDUCIVE ENOUGH TO POP A FEW SCT
LATE DAY SHOWERS/STORMS. 20% POPS EXTEND AS FAR NORTH AS POLK
COUNTY ALONG THE SOUTHERN EDGE OF THE BOUNDARY...AND THEN HAVE
CHANCE 30% POPS OVER THE SOUTHERN ZONES (MAINLY AWAY FROM THE
BEACHES).
TONIGHT...
ANY ISOLATED EVENING STORMS WILL DISSIPATE QUICKLY WITH THE LOSS
OF DIURNAL HEATING. UPPER RIDGE AXIS WILL BE SHIFTING EASTWARD AND
BE CENTERED OVER THE EASTERN GULF OF MEXICO BY EARLY SATURDAY
MORNING. SEVERAL UPPER LEVEL SHORTWAVE FEATURES WILL COMBINE WITH
EFFICIENT WAA REGIME TO RESULT IN AN ACTIVE CONVECTION NIGHT
ACROSS THE LOWER MS VALLEY OVER TO AL/GA. HOWEVER...HIGH PRESSURE
SHIFTING OFF THE EASTERN SEABOARD WILL RIDGE BACK TO THE SOUTHWEST
OVER OUR HEADS. THIS STACKED RIDGING REGIME SHOULD BE PLENTY TO
PROTECT OUR ZONES AND KEEP THIS INCLEMENT WEATHER WELL TO OUR
NORTH AND NORTHWEST THROUGH THE OVERNIGHT.
SATURDAY...
STRONG SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW WILL EJECT OUT
OF THE CENTRAL PLAINS INTO THE OHIO/TN VALLEYS...WHILE A SERIES OF
WEAKER IMPULSES RIDE EASTWARD ALONG THE NORTH-CENTRAL GULF COAST.
THE MOVEMENT OF THESE MASS FIELDS WILL RESULT IN A DE-
AMPLIFICATION OF THE UPPER RIDGE OVER OUR REGION THROUGH THE DAY.
WARM FRONTAL BOUNDARY WILL BE ALIGNED TO THE NORTH OF THE I-10
CORRIDOR WITH QUITE A BIT OF ONGOING SHOWER AND STORM ACTIVITY
FROM THE FLORIDA PANHANDLE TO AL/GA. THE QUESTION FOR OUR FORECAST
WILL BE HOW THE WEST COAST SEA-BREEZE BEHAVES THROUGH THE DAY.
GENERALLY SPEAKING...THE GOOD SYNOPTIC SETUP FOR LIFT WILL REMAIN
TO OUR NORTH TOMORROW...BUT WE WILL HAVE THE SEA-BREEZE TO PROVIDE
AT LEAST SOME FOCUS. WIND FIELDS EVOLVE FAVORABLY TOWARD ORGANIZED
CONVECTIVE POTENTIAL DURING THE DAY (ESPECIALLY NORTH OF TAMPA
BAY)...WITH 0-6KM SHEAR VALUES ELEVATING TO BETWEEN 40-45 KNOTS
OVER OUR NORTHERN ZONES. THESE VALUES...ALTHOUGH NOT
EXTREME...ARE CAPABLE OF SUSTAINING ORGANIZED CONVECTION. HERE IS
THE PROBLEM FOR OUR AREA...THE 1000-700MB FLOW TOMORROW IS FROM
THE W/SW AT 15-25 KNOTS. FIRST OF ALL...THIS WILL KEEP THE WEST
COAST SEA- BREEZE FAIRLY WEAK AND DISORGANIZED. SECOND...THE
BOUNDARY WILL VERY QUICKLY TRANSLATE INLAND. WITH THIS IN
MIND...CURRENT THINKING IS THAT THE BEST CHANCES FOR AFTERNOON
THUNDER WOULD BE OVER TOWARD THE FLORIDA EAST COAST...WHERE SEA-
BREEZE COLLISION WILL TAKE PLACE. IT IS A TOUGH CALL SINCE ANY
CONVECTION THAT DOES DEVELOP WILL BE MOVING QUICKLY AND COULD
TRANSLATE STRONGER WIND MOMENTUM TO THE GROUND. JUST UNSURE THAT
MUCH CONVECTION WILL EVEN TAKE PLACE OVER OUR ZONES IN THE FIRST
PLACE. BETTER CHANCES FOR THE STORMS SHOULD STAY MAINLY EAST AND
NORTH OF OUR ZONES.
&&
.LONG TERM (SUNDAY THROUGH NEXT FRIDAY)...
SUN - A PACIFIC NORTHWEST SHORT WAVE TROUGH DROPS INTO THE FOUR CORNERS
AREA AND CUTS-OFF AS A TROUGH FROM THE LOWER GREAT LAKES TO THE MID-
ATLANTIC STATES SLIDES OUT OVER THE ATLANTIC...WITH NEARLY ZONAL/FLAT
RIDGING ACROSS THE GULF REGION. A WEAK FRONTAL BOUNDARY OVER THE GULF
COASTAL STATES SHIFTS DOWN INTO FL WITH AN ATLANTIC SURFACE RIDGE...
INITIALLY ACROSS FL...SLIPPING SOUTH OF THE STATE.
MON -TUE - THE FOUR CORNERS LOW OPENS AS IT TRACKS TO THE EASTERN
PLAINS...WITH TROUGHINESS DROPPING INTO THE WEST GULF AS RIDGING IN THE
EAST GULF SLIDES ACROSS FL. THE FRONTAL BOUNDARY ACROSS THE STATE LIFTS
NORTH WITH A LOW FORMING ON THE WESTERN PORTION...OVER THE CENTRAL GULF
OR GULF COAST.
WED-THU - THE EASTERN PLAINS TROUGH MOVES TO THE EASTERN SEABOARD...AS
A TROUGH OR CLOSED LOW...WITH SOUTHWESTERLY FLOW ALOFT STREAMING SOME
DEEPER MOISTURE ACROSS THE GULF AND MUCH OF FL. THE SURFACE LOW TREKS
EAST OR EAST-NORTHEAST WITH A TRAILING COLD FRONT SWINGING INTO FL.
FRI - THE UPPER TROUGH/LOW EXITS THE EASTERN SEABOARD AS UPPER RIDGING
BUILDS OVER THE NATIONS/S MID-SECTION. SURFACE HIGH PRESSURE SETTLES IN
ACROSS THE PLAINS OR THE MISSISSIPPI VALLEY WITH THE FL BOUNDARY GETTING
PUSHED TO OR OFFSHORE FAR SOUTH FL.
SENSIBLE WEATHER AND FORECAST - THE UP-COMING WEEK IS A COMPLEX PATTERN
WITH THE GFS/ECMWF/CMC MODELS NOT IN VERY GOOD AGREEMENT AND PERHAPS
OVERDOING SOME OF THE SMALLER DETAILS. IN ANY CASE...EXPECT MOIST TO
WET CONDITIONS THROUGH MOST OF THE PERIOD WITH SHOWERS AND STORMS. THE MOST
COVERAGE WILL BE TUE INTO WED AHEAD OF THE FRONT...SOME OF THESE STORMS
MAY BECOME STRONG AND THERE COULD BE SOME FLOODING CONCERNS. FINALLY BY THE
LAST SOME DAY SOME DRIER AND COOLER AIR WILL BEGIN TO SWEEP IN FROM THE
NORTH.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA
TERMINALS. EXPECT THESE CONDITIONS TO PERSIST THROUGH THE EVENING
HOURS...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR A SHOWER OR
STORM FOR KPGD/KFMY/KRSW. ANY SHOWERS SHOULD DISSIPATE QUICKLY
AROUND SUNSET. WINDS SHIFT SOUTH AND THEN SOUTHWEST DURING
SATURDAY AND BECOME GUSTY AT TIMES. MOST OF THE SHOWERS AND
STORMS ARE EXPECTED TO OCCUR TO THE EAST OF THE FORECAST
TERMINALS...SO TAFS SHOW PREVAILING VFR.
&&
.MARINE...
WINDS WILL SHIFT TO THE SOUTHEAST TONIGHT AND THEN SOUTHERLY AND
SOUTHWESTERLY ON SATURDAY AS HIGH PRESSURE SHIFTS OFF THE
SOUTHEAST COAST AND RIDGES BACK TO THE WEST OVER SOUTH FLORIDA
AND THE FLORIDA STRAITS. A PERIOD OF CAUTIONARY LEVEL WINDS IS
EXPECTED TONIGHT OVER THE NORTHERN WATERS...WITH SOUTHERLY FLOW
AT TIMES APPROACHING CAUTIONARY LEVELS OVER THE REMAINDER OF
THE FORECAST WATERS DURING THE UPCOMING WEEKEND.
&&
.FIRE WEATHER...
A FRONT BISECTS THE STATE THIS AFTERNOON SEPARATING DRIER
CONDITIONS NORTH OF THE I-4 CORRIDOR FROM MORE MOIST AND
HUMID CONDITIONS TO THE SOUTH. THIS BOUNDARY WILL DISSIPATE
AND LIFT NORTH INTO SATURDAY AS SOUTHERLY FLOW DEVELOPS AND
ADVECTS HIGHER MOISTURE BACK ACROSS THE REST OF THE STATE.
WITH RELATIVE HUMIDITY VALUES ABOVE CRITICAL LEVELS...THE
ONLY FIRE WEATHER CONCERNS WILL BE HIGH DISPERSION INDICES
ON SATURDAY.
FOG POTENTIAL...NO SIGNIFICANT FOG IS EXPECTED THROUGH THE
UPCOMING WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 74 84 76 85 / 0 10 20 30
FMY 74 86 76 90 / 10 10 0 20
GIF 70 89 73 87 / 10 30 10 30
SRQ 73 84 77 85 / 0 10 10 30
BKV 68 88 70 86 / 0 10 30 40
SPG 74 84 77 83 / 0 10 20 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT FROM SATURDAY MORNING THROUGH
SUNDAY EVENING FOR COASTAL CHARLOTTE-COASTAL LEE-
COASTAL MANATEE-COASTAL SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...14/MROCZKA
LONG TERM...09/RUDE
DECISION SUPPORT...09/RUDE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
515 PM CDT FRI APR 24 2015
.SHORT TERM...
323 PM CDT
THROUGH SATURDAY NIGHT...
SHORT TERM...THROUGH SATURDAY NIGHT...
PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE
SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN
AND AMOUNTS.
DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH
GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT
WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT
WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN
OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE
LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO
AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH
OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY
SHOULD BE IN FAR NORTHERN CWA.
LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD
WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH
MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL
MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN
WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO
SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES
ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW
LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN
STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS
ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY
PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY
RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL
SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES
THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE
AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE
RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND
SKIES CLEARING TOWARD EARLY SUNDAY.
RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY
SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS
OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW-
MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO
SHIFT.
REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO
GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE.
CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW
CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID
40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF
I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8
TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN
INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE
ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION.
RC
&&
.LONG TERM...
333 PM CDT
SUNDAY THROUGH FRIDAY...
EXTENDED PERIOD THROUGH AT LEAST THURSDAY WILL BE DOMINATED BY
ONSHORE FLOW AND COOLER CONDITIONS NEAR THE LAKE...BUT ALSO
GRADUAL WARMING INLAND. WITH POSSIBLY MINOR EXCEPTION OF
WEDNESDAY...CONDITIONS SHOULD BE PRIMARILY DRY AS WELL. AIRMASS
WILL BE COOLEST SUNDAY THROUGH EARLY MONDAY...WITH ONLY MID-UPPER
40S ALONG SHORE AND MID-UPPER 50S INLAND AND THEN OVERNIGHT LOWS
SUNDAY NIGHT AWAY FROM CHICAGO HEAT ISLAND IN LOWER-MID 30S. AS
HIGH PRESSURE DROPS SOUTHEAST TOWARD EARLY MONDAY...WINDS MAY
DIMINISH ENOUGH TO SUPPORT AT LEAST PATCHY FROST...BUT HAVE NOT
ADDED IT TO GRIDS YET. INLAND HIGHS SHOULD BE INTO THE 60S EACH
DAY MON-THU AND TEMPS COULD APPROACH 70 NEXT FRIDAY.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER
TONIGHT AND SATURDAY MORNING.
* AREA OF LIGHT RAIN EXPECTED TO MOVE IN BY 00Z...WITH GREATEST
COVERAGE FROM ORD NORTH. UPSTREAM CONDITIONS INDICATE VFR CIGS
WITH OCNL MVFR VIS WITH RA/SHRA. RAIN LINGERING THROUGH 03Z OR
SO WITH A LULL POSSIBLE AFTER THAT.
* RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY
WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET.
//DISCUSSION...UPDATED 18Z...
SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION
AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS
SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST
ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT
WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED.
MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE
IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL
INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS
THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT
RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER
DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN
WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF
SITES.
THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY
THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE
PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE
MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR
LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS
WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF
THE AREA.
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM-HIGH IN WINDS.
* MEDIUM-HIGH IN PERIOD OF LIGHT RAIN/SHOWERS STARTING AROUND 00Z
ESPECIALLY FROM ORD NORTH AND WEST. MEDIUM HIGH IN VFR CIGS AND
VFR/MVFR VIS IN HEAVIER SHOWERS.
* HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
* SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY
WINDS.
MTF/RATZER
&&
.MARINE...
215 PM CDT
HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET
UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE
LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A
LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION
THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN
MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST
FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY
LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY
STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE
ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH
PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND
SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE
SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO
VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO
NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN
PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL
CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL
CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH
SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO
MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY
TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF
NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER
THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
334 PM CDT FRI APR 24 2015
.SHORT TERM...
323 PM CDT
THROUGH SATURDAY NIGHT...
SHORT TERM...THROUGH SATURDAY NIGHT...
PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE
SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN
AND AMOUNTS.
DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH
GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT
WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT
WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN
OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE
LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO
AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH
OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY
SHOULD BE IN FAR NORTHERN CWA.
LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD
WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH
MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL
MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN
WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO
SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES
ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW
LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN
STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS
ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY
PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY
RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL
SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES
THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE
AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE
RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND
SKIES CLEARING TOWARD EARLY SUNDAY.
RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY
SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS
OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW-
MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO
SHIFT.
REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO
GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE.
CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW
CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID
40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF
I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8
TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN
INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE
ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION.
RC
&&
.LONG TERM...
333 PM CDT
SUNDAY THROUGH FRIDAY...
EXTENDED PERIOD THROUGH AT LEAST THURSDAY WILL BE DOMINATED BY
ONSHORE FLOW AND COOLER CONDITIONS NEAR THE LAKE...BUT ALSO
GRADUAL WARMING INLAND. WITH POSSIBLY MINOR EXCEPTION OF
WEDNESDAY...CONDITIONS SHOULD BE PRIMARILY DRY AS WELL. AIRMASS
WILL BE COOLEST SUNDAY THROUGH EARLY MONDAY...WITH ONLY MID-UPPER
40S ALONG SHORE AND MID-UPPER 50S INLAND AND THEN OVERNIGHT LOWS
SUNDAY NIGHT AWAY FROM CHICAGO HEAT ISLAND IN LOWER-MID 30S. AS
HIGH PRESSURE DROPS SOUTHEAST TOWARD EARLY MONDAY...WINDS MAY
DIMINISH ENOUGH TO SUPPORT AT LEAST PATCHY FROST...BUT HAVE NOT
ADDED IT TO GRIDS YET. INLAND HIGHS SHOULD BE INTO THE 60S EACH
DAY MON-THU AND TEMPS COULD APPROACH 70 NEXT FRIDAY.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER
TONIGHT AND SATURDAY MORNING.
* SCATTERED LIGHT RAIN SHOWERS AT LEAST NEARBY THROUGH 03Z OR SO.
* RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY
WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET.
//DISCUSSION...UPDATED 18Z...
SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION
AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS
SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST
ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT
WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED.
MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE
IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL
INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS
THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT
RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER
DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN
WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF
SITES.
THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY
THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE
PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE
MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR
LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS
WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF
THE AREA.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH IN WINDS.
* LOW-MEDIUM IN SCATTERED LIGHT RAIN SHOWERS THROUGH MID-EVENING.
HIGH THAT IF ANY SHOWERS OCCUR THEY WILL BE LIGHT WITH VFR
CONDITIONS.
* HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
* SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY
WINDS.
MTF
&&
.MARINE...
215 PM CDT
HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET
UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE
LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A
LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION
THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN
MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST
FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY
LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY
STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE
ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH
PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND
SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE
SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO
VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO
NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN
PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL
CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL
CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH
SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO
MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY
TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF
NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER
THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
324 PM CDT FRI APR 24 2015
.SHORT TERM...
323 PM CDT
THROUGH SATURDAY NIGHT...
SHORT TERM...THROUGH SATURDAY NIGHT...
PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE
SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN
AND AMOUNTS.
DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH
GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT
WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT
WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN
OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE
LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO
AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH
OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY
SHOULD BE IN FAR NORTHERN CWA.
LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD
WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH
MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL
MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN
WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO
SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES
ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW
LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN
STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS
ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY
PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY
RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL
SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES
THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE
AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE
RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND
SKIES CLEARING TOWARD EARLY SUNDAY.
RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY
SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS
OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW-
MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO
SHIFT.
REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO
GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE.
CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW
CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID
40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF
I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8
TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN
INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE
ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION.
RC
&&
.LONG TERM...
323 PM CDT
SUNDAY THROUGH FRIDAY...
TO BE ISSUED SHORTLY.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER
TONIGHT AND SATURDAY MORNING.
* SCATTERED LIGHT RAIN SHOWERS AT LEAST NEARBY THROUGH 03Z OR SO.
* RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY
WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET.
//DISCUSSION...UPDATED 18Z...
SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION
AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS
SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST
ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT
WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED.
MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE
IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL
INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS
THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT
RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER
DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN
WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF
SITES.
THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY
THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE
PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE
MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR
LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS
WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF
THE AREA.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH IN WINDS.
* LOW-MEDIUM IN SCATTERED LIGHT RAIN SHOWERS THROUGH MID-EVENING.
HIGH THAT IF ANY SHOWERS OCCUR THEY WILL BE LIGHT WITH VFR
CONDITIONS.
* HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
* SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY
WINDS.
MTF
&&
.MARINE...
215 PM CDT
HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET
UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE
LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A
LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION
THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN
MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST
FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY
LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY
STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE
ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH
PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND
SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE
SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO
VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO
NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN
PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL
CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL
CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH
SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO
MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY
TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF
NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER
THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS GOODLAND KS
435 PM MDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 201 PM MDT FRI APR 24 2015
AT 1PM MDT VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS
SHOWED PARTLY TO MOSTLY CLOUDY SKIES FOR LOCATIONS ACROSS THE TRI
STATE AREA WEST OF HIGHWAY 83...WITH LOWER BROKEN TO OVERCAST
CONDITIONS EAST OF THE HIGHWAY AHEAD OF AN ADVANCING WARM FRONTAL
BOUNDARY. CUMULUS DEVELOPMENT WAS BEGINNING TO DEVELOP ON RADAR
AND SATELLITE IMAGERY ALONG A TROUGH/DRY LINE IN EASTERN COLORADO.
RAP AND WATER VAPOR IMAGERY SHOWED AN UPPER LEVEL SHORTWAVE TROUGH
BEGINNING TO TAKE A NEGATIVE TILT INTO THE CENTRAL AND SOUTHER
HIGH PLAINS.
THE LATEST HRRR GUIDANCE WAS SHOWING CONVECTIVE INITIATION AT
20Z...ALTHOUGH CELLS ARE ALREADY BEGINNING TO DEVELOP. NMM AND ARW
GUIDANCE IS ALSO A BIT BEHIND REALITY WITH HAVING CONVECTION DEVELOP
BETWEEN 21Z AND 00Z. 0-1 KM AND 0-3 KM HELICITY WAS NOT IMPRESSIVE
WITH WIDESPREAD VALUES UNDER 50 FOR THE FORECAST AREA...SO NOT
EXPECTING TORNADOES TO BE A WIDESPREAD THREAT THIS AFTERNOON WITH
DEVELOPING STORMS. HOWEVER...0-6 KM BULK SHEAR APPROACHING 35-40 KTS
ACROSS THE AREA IN COMBINATION WITH 1500 J/KG OF CAPE SUGGESTS A
LARGE HAIL THREAT. WITH DCAPE VALUES MOSTLY BETWEEN 400 AND 500
J/KG...ISOLATED SEVERE WIND GUSTS FROM STORMS IS POSSIBLE...BUT
EXPECTING THUNDERSTORMS THIS AFTERNOON TO PRIMARILY HAVE A LARGE
HAIL THREAT. STORMS WILL GET GOING BY MID AFTERNOON AND LAST THROUGH
THE EVENING.
CLOUD COVER WILL BE PRESENT LATE THIS EVENING DUE TO A STEADY STREAM
OF MOISTURE MOVING INTO THE FORECAST AREA...HOWEVER A SHORTWAVE
RIDGE ALOFT WILL BEGIN TO FORM ACROSS THE AREA AND BRING DRIER AIR
INTO THE AREA OVERNIGHT. LOW TEMPERATURES WILL BE SLIGHTLY WARMER
THAN NORMAL IN THE MID TO UPPER 40S.
DRY AND WARM CONDITIONS WILL BE PRESENT TOMORROW WITH THE SHORTWAVE
UPPER LEVEL RIDGE THAT WILL MOVE INTO THE AREA...ALTHOUGH DRY
WEATHER WILL BE SHORT LIVED AS ANOTHER TROUGH WITH A CUT OFF LOW
FEATURE MOVES INTO THE COLORADO FRONT RANGE AND BRINGS CHANCES FOR
SHOWERS AND THUNDERSTORMS. THERE ARE SOME LOCATIONS WITH CAPE VALUES
APPROACHING 700 J/KG AND 0-6 BULK SHEAR APPROACHING 35 KTS...HOWEVER
FORECAST AREAS IN MODELS DO NOT NECESSARILY LINE UP.
THEREFORE...NOT EXPECTING A WIDE SEVERE WEATHER THREAT SATURDAY
AFTERNOON...ALTHOUGH AN ISOLATED SEVERE THUNDERSTORM THREAT WILL
EXIST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 201 PM MDT FRI APR 24 2015
SATURDAY NIGHT-MONDAY...LARGE SCALE UPPER LOW CLOSES OFF JUST SOUTH
OF FOUR CORNERS REGION SATURDAY NIGHT AND MOVES ACROSS THE SOUTHERN
PLAINS THROUGH MONDAY NIGHT. A COLD FRONT WILL DROP SOUTH ACROSS THE
THE CWA LATE SATURDAY NIGHT AND SUNDAY AND STALL SOUTH AND WEST OF
OUR CWA. SOUTHERLY THEN EASTERLY FLOW WILL BRING VERY GOOD MOISTURE
ADVECTION INTO OUR CWA AS THIS UPPER LEVEL FEATURE MOVES EAST WITH
OVERRUNNING NORTH OF THE STALLED FRONTAL ZONE WHERE ELEVATED
FRONT/FRONTOGENETIC FORCING WILL BE IN PLACE. BETTER PRECIP
SIGNAL IS CURRENTLY SATURDAY NIGHT THROUGH SUNDAY ACROSS THE
WESTERN AND SOUTHWESTERN PART OF THE CWA...WHERE I CONTINUED TREND
OF RAISING POPS. IT STILL LOOKS LIKE WE COULD SEE LIGHT PRECIP
PERSIST AT LEAST THROUGH LATE SUNDAY NIGHT BEFORE DRIER AIR BEGINS
TO ADVECT SOUTH AND SUBSIDENCE BUILDS SOUTHWEST MONDAY.
IF CURRENT SIGNAL/TREND CONTINUE I COULD SEE RAISING POPS TO
CATEGORICAL LATE SATURDAY NIGHT/SUNDAY...AND TO LIKELY CATEGORY
SUNDAY NIGHT THROUGH MONDAY. WHILE 40KM GUIDANCE SHOWS QPF AS FAR
EAST AS NORTON/GRAHAM THROUGH THESE PERIODS...PATTERN TENDS TO FAVOR
AREAS CLOSER TO FRONTAL ZONE/HIGHER TERRAIN IN COLORADO...SO I
KEPT LOWERS POPS NORTHEAST/EAST. IN POST FRONTAL ENVIRONMENT WITH
THICK STRATUS/LIKELY PRECIPITATION HIGH TEMPS WILL BE COOLER AND I
CONTINUED THE TREND OF LOWER HIGHS ESPECIALLY SUNDAY WHEN HIGHS
MAY STRUGGLE TO REACH THE UPPER 40S IN SOME AREAS.
MONDAY NIGHT-FRIDAY...THERE IS A SECONDARY H3 JET ROTATING THROUGH
THE NORTHERN PLAINS BEHIND THE LARGE SCALE TROUGH...AND THIS COULD
BRING ANOTHER QUICK SHOT OF LIGHT SHOWERS....OTHERWISE LARGE SCALE
RIDGING WILL BRING DRY CONDITIONS AND A WARMING TREND BACK TO THE
REGION THROUGH THURSDAY. MUCH WARMER CONDITIONS ARE EXPECTED BY
NEXT FRIDAY (80S) AS LEE TROUGH STRENGTHENS. WHILE THERE ISN`T A
LOT OF AGREEMENT AT THIS RANGE THE PATTERN DOES SUPPORT POSSIBLE
AFTERNOON/EVENING THUNDERSTORM DEVELOPMENT IN THE HIGHER TERRAIN
IN COLORADO MOVING EAST INTO THE WESTERN PORTIONS OF OUR CWA...SO
SLIGHT CHANCE POPS WERE KEPT IN PLACE FRIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 430 PM MDT FRI APR 24 2015
KGLD...VFR THROUGH THE PERIOD. THROUGH 01Z OR 02Z WINDS GENERALLY
FROM THE NORTHEAST 5-10KTS BUT WITH VARIOUS OUTFLOW BOUNDARIES
FROM THUNDERSTORMS ERRATIC AND GUSTY WINDS POSSIBLE. 02Z-14Z WINDS
FROM THE WEST NEAR 10KTS WITH ONLY A FEW CLOUDS EXPECTED. 14Z-18Z
WINDS VEER TO THE NORTHWEST AROUND 12KTS WITH SKC CONDITIONS
EXPECTED. 18Z THROUGH THE REST OF THE TAF PERIOD WINDS CONTINUE TO
VEER TO THE NORTH (18Z) THEN NORTHEAST (22Z) AT 11KTS OR LESS. MAY
SEE A FEW CU DEVELOP AROUND 18Z BUT MORE LIKELY LATER IN THE
AFTERNOON AS A WEATHER DISTURBANCE APPROACHES FROM THE WEST.
KMCK...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 05Z WINDS
VARIABLE WINDS 6KTS OR LESS. 06Z-15Z MODELS HINT AT SOME LOW LEVEL
MOISTURE IN THE BOUNDARY LAYER THAT MAY BE ENOUGH TO PRODUCE A
SCATTERED TO BROKEN DECK. FOR NOW HAVE A SCATTERED DECK. WINDS
BECOMING NORTHWEST 5-10KTS. 16Z THROUGH THE REST OF THE TAF PERIOD
AM EXPECTING NORTHWEST WINDS TO VEER TO THE NORTHEAST THEN EAST-
NORTHEAST UNDER 10KTS. SHOULD SEE A BROKEN DECK OF CLOUDS AROUND
4K FT FOR MUCH OF THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...MK
LONG TERM...DR
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
203 PM MDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 201 PM MDT FRI APR 24 2015
AT 1PM MDT VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS
SHOWED PARTLY TO MOSTLY CLOUDY SKIES FOR LOCATIONS ACROSS THE TRI
STATE AREA WEST OF HIGHWAY 83...WITH LOWER BROKEN TO OVERCAST
CONDITIONS EAST OF THE HIGHWAY AHEAD OF AN ADVANCING WARM FRONTAL
BOUNDARY. CUMULUS DEVELOPMENT WAS BEGINNING TO DEVELOP ON RADAR
AND SATELLITE IMAGERY ALONG A TROUGH/DRY LINE IN EASTERN COLORADO.
RAP AND WATER VAPOR IMAGERY SHOWED AN UPPER LEVEL SHORTWAVE TROUGH
BEGINNING TO TAKE A NEGATIVE TILT INTO THE CENTRAL AND SOUTHER
HIGH PLAINS.
THE LATEST HRRR GUIDANCE WAS SHOWING CONVECTIVE INITIATION AT
20Z...ALTHOUGH CELLS ARE ALREADY BEGINNING TO DEVELOP. NMM AND ARW
GUIDANCE IS ALSO A BIT BEHIND REALITY WITH HAVING CONVECTION DEVELOP
BETWEEN 21Z AND 00Z. 0-1 KM AND 0-3 KM HELICITY WAS NOT IMPRESSIVE
WITH WIDESPREAD VALUES UNDER 50 FOR THE FORECAST AREA...SO NOT
EXPECTING TORNADOES TO BE A WIDESPREAD THREAT THIS AFTERNOON WITH
DEVELOPING STORMS. HOWEVER...0-6 KM BULK SHEAR APPROACHING 35-40 KTS
ACROSS THE AREA IN COMBINATION WITH 1500 J/KG OF CAPE SUGGESTS A
LARGE HAIL THREAT. WITH DCAPE VALUES MOSTLY BETWEEN 400 AND 500
J/KG...ISOLATED SEVERE WIND GUSTS FROM STORMS IS POSSIBLE...BUT
EXPECTING THUNDERSTORMS THIS AFTERNOON TO PRIMARILY HAVE A LARGE
HAIL THREAT. STORMS WILL GET GOING BY MID AFTERNOON AND LAST THROUGH
THE EVENING.
CLOUD COVER WILL BE PRESENT LATE THIS EVENING DUE TO A STEADY STREAM
OF MOISTURE MOVING INTO THE FORECAST AREA...HOWEVER A SHORTWAVE
RIDGE ALOFT WILL BEGIN TO FORM ACROSS THE AREA AND BRING DRIER AIR
INTO THE AREA OVERNIGHT. LOW TEMPERATURES WILL BE SLIGHTLY WARMER
THAN NORMAL IN THE MID TO UPPER 40S.
DRY AND WARM CONDITIONS WILL BE PRESENT TOMORROW WITH THE SHORTWAVE
UPPER LEVEL RIDGE THAT WILL MOVE INTO THE AREA...ALTHOUGH DRY
WEATHER WILL BE SHORT LIVED AS ANOTHER TROUGH WITH A CUT OFF LOW
FEATURE MOVES INTO THE COLORADO FRONT RANGE AND BRINGS CHANCES FOR
SHOWERS AND THUNDERSTORMS. THERE ARE SOME LOCATIONS WITH CAPE VALUES
APPROACHING 700 J/KG AND 0-6 BULK SHEAR APPROACHING 35 KTS...HOWEVER
FORECAST AREAS IN MODELS DO NOT NECESSARILY LINE UP.
THEREFORE...NOT EXPECTING A WIDE SEVERE WEATHER THREAT SATURDAY
AFTERNOON...ALTHOUGH AN ISOLATED SEVERE THUNDERSTORM THREAT WILL
EXIST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 201 PM MDT FRI APR 24 2015
SATURDAY NIGHT-MONDAY...LARGE SCALE UPPER LOW CLOSES OFF JUST SOUTH
OF FOUR CORNERS REGION SATURDAY NIGHT AND MOVES ACROSS THE SOUTHERN
PLAINS THROUGH MONDAY NIGHT. A COLD FRONT WILL DROP SOUTH ACROSS THE
THE CWA LATE SATURDAY NIGHT AND SUNDAY AND STALL SOUTH AND WEST OF
OUR CWA. SOUTHERLY THEN EASTERLY FLOW WILL BRING VERY GOOD MOISTURE
ADVECTION INTO OUR CWA AS THIS UPPER LEVEL FEATURE MOVES EAST WITH
OVERRUNNING NORTH OF THE STALLED FRONTAL ZONE WHERE ELEVATED
FRONT/FRONTOGENETIC FORCING WILL BE IN PLACE. BETTER PRECIP
SIGNAL IS CURRENTLY SATURDAY NIGHT THROUGH SUNDAY ACROSS THE
WESTERN AND SOUTHWESTERN PART OF THE CWA...WHERE I CONTINUED TREND
OF RAISING POPS. IT STILL LOOKS LIKE WE COULD SEE LIGHT PRECIP
PERSIST AT LEAST THROUGH LATE SUNDAY NIGHT BEFORE DRIER AIR BEGINS
TO ADVECT SOUTH AND SUBSIDENCE BUILDS SOUTHWEST MONDAY.
IF CURRENT SIGNAL/TREND CONTINUE I COULD SEE RAISING POPS TO
CATEGORICAL LATE SATURDAY NIGHT/SUNDAY...AND TO LIKELY CATEGORY
SUNDAY NIGHT THROUGH MONDAY. WHILE 40KM GUIDANCE SHOWS QPF AS FAR
EAST AS NORTON/GRAHAM THROUGH THESE PERIODS...PATTERN TENDS TO FAVOR
AREAS CLOSER TO FRONTAL ZONE/HIGHER TERRAIN IN COLORADO...SO I
KEPT LOWERS POPS NORTHEAST/EAST. IN POST FRONTAL ENVIRONMENT WITH
THICK STRATUS/LIKELY PRECIPITATION HIGH TEMPS WILL BE COOLER AND I
CONTINUED THE TREND OF LOWER HIGHS ESPECIALLY SUNDAY WHEN HIGHS
MAY STRUGGLE TO REACH THE UPPER 40S IN SOME AREAS.
MONDAY NIGHT-FRIDAY...THERE IS A SECONDARY H3 JET ROTATING THROUGH
THE NORTHERN PLAINS BEHIND THE LARGE SCALE TROUGH...AND THIS COULD
BRING ANOTHER QUICK SHOT OF LIGHT SHOWERS....OTHERWISE LARGE SCALE
RIDGING WILL BRING DRY CONDITIONS AND A WARMING TREND BACK TO THE
REGION THROUGH THURSDAY. MUCH WARMER CONDITIONS ARE EXPECTED BY
NEXT FRIDAY (80S) AS LEE TROUGH STRENGTHENS. WHILE THERE ISN`T A
LOT OF AGREEMENT AT THIS RANGE THE PATTERN DOES SUPPORT POSSIBLE
AFTERNOON/EVENING THUNDERSTORM DEVELOPMENT IN THE HIGHER TERRAIN
IN COLORADO MOVING EAST INTO THE WESTERN PORTIONS OF OUR CWA...SO
SLIGHT CHANCE POPS WERE KEPT IN PLACE FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1134 AM MDT FRI APR 24 2015
IN THE IMMEDIATE TERM FOR KMCK...A PESKY LAYER OF MVFR OVERCAST
SKIES WILL CONTINUE FOR THE EARLY AFTERNOON HOURS. LOWER CEILINGS
SHOULD IMPROVE MY MID AFTERNOON.
AN APPROACHING UPPER LEVEL DISTURBANCE WILL BRING SHOWERS AND
THUNDERSTORMS IN THE VICINITY OF THE TAF SITES THIS AFTERNOON. DUE
TO LACK OF CONFIDENCE IN THE EXACT TRACK OF THE STORMS...ONLY PUT
VCTS MENTION IN THE FORECAST. OVERCAST SKIES WILL BE PRESENT
OVERNIGHT UNTIL THE MORNING HOURS WHEN SKIES BEGIN TO CLEAR. VFR
CONDITIONS WILL PREVAIL FOR BOTH KMCK AND KGLD OVERNIGHT THROUGH
THE END OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...MK
LONG TERM...DR
AVIATION...MK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
111 PM CDT FRI APR 24 2015
...UPDATED LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1234 PM CDT FRI APR 24 2015
THE SHORT-FUSE SEVERE WEATHER COMPOSITE AT MIDDAY WAS SHOWING A
THREAT AREA STARTING TO DEVELOP ALONG THE SLOWLY NORTHWARD ADVANCING
WARM FRONT ACROSS WEST-CENTRAL KANSAS. SURFACE-BASED CAPE WAS
APPROACHING 1000 J/KG PER LAPS ANALYSIS AS OF 16Z. A SYNOPTIC DRY
INTRUSION/DRYLINE WILL CONTINUE TO ADVANCE NORTHEASTWARD, SHUNTING
THE SURFACE-BASED INGREDIENTS FOR SEVERE THUNDERSTORMS UP TOWARD THE
I-70 CORRIDOR. BY 21Z, THE HRRR INDICATES DEEP MOIST CONVECTION
DEVELOPING ALONG THE WARM FRONT BY 20-21Z. THERE SHOULD BE PRETTY
GOOD LOW LEVEL SHEAR ALONG THE FRONT WITH AMPLE STREAMWISE VORTICITY
TO INGEST INTO AN INCIPIENT SUPERCELL STORM. THE HRRR HAS SHOWN A
PERSISTENT LONG-TRACK UPDRAFT HELICITY SIGNAL, WHICH WOULD SUPPORT A
FAIRLY LONG-LIVED SUPERCELL THUNDERSTORM. IT CERTAINLY APPEARS THE
BEST TORNADO THREAT WILL BE UP ALONG THE FRONT ALONG THE I-70
CORRIDOR, WITH THE MOST VIGOROUS SURFACE-BASED STORMS EXITING OUR
AREA OF RESPONSIBILITY (EAST OF ELLIS AND RUSH COUNTY) BY AS SOON AS
23Z. WE WILL HAVE TO WATCH THE BENT-BACK REGION OF ENHANCED
CAPE/MOISTURE WESTWARD ALONG I-70 FOR FUTURE GROWTH OF DEEP MOIST
CONVECTION AS SOME OF THE LATEST RUNS OF THE HRRR SUGGEST. THERE
WILL LIKELY BE A LOCALIZED HEAVY RAIN RISK ALONG THE FRONT UP THERE
SHOULD THE HRRR PAN OUT. THE SHORTWAVE TROUGH WILL QUICKLY EXIT THE
SOUTHWEST KANSAS REGION BY LATE EVENING WITH SOME WESTERLY LOW LEVEL
MOMENTUM FINALLY PUSHING INTO OUR REGION ESPECIALLY AFTER 06Z
TONIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 111 PM CDT FRI APR 24 2015
BY THE BEGINNING OF THE EXTENDED PERIOD, AN UPPER TROUGH WILL BE BE
DEEPENING OVER THE WESTERN STATES THANKS TO A 120+ KNOT JET LOCATED
ON THE WEST SIDE OF THE TROUGH. THIS TROUGH WILL CONTINUE TO DEEPEN
AND CLOSE OFF INTO AN UPPER LOW OVER NEW MEXICO ON SUNDAY BEFORE
MOVING OUT ACROSS THE SOUTHERN PLAINS EARLY NEXT WEEK. AS THE TROUGH
AND LOW DEVELOP, LOW PRESSURE OVER EASTERN COLORADO WILL DROP SOUTH
INTO THE TEXAS PANHANDLE WHILE A COOL FRONT DROPS SOUTH ACROSS
WESTERN KANSAS SATURDAY NIGHT. COOL AND MOIST LOW LEVEL EASTERLY
FLOW WILL DEVELOP OVER SOUTHWEST KANSAS BEHIND THE FRONT. THIS WILL
LEAD TO CLOUDY AND COOLER CONDITIONS ALONG WITH INCREASING CHANCES
FOR SHOWERS AND POSSIBLY A FEW THUNDERSTORMS LATE SUNDAY THROUGH THE
EARLY PART OF NEXT WEEK.
THE MEDIUM RANGE MODELS HAVE BEEN HOLDING ON TO THEIR RESPECTIVE
SOLUTIONS REGARDING THE TRACK OF THE UPPER LOW AS IT MOVES OUT
THROUGH THE SOUTHERN PLAINS MONDAY AND TUESDAY. THE TRACK OF THE LOW
WILL HAVE AN IMPACT ON PRECIPITATION CHANCES AND RAINFALL AMOUNTS
ACROSS SOUTHWEST KANSAS. THE GFS CONTINUES TO BE FARTHEST NORTH WITH
ITS TRACK ACROSS THE TEXAS PANHANDLE THROUGH OKLAHOMA INTO MISSOURI.
THIS MODEL IS SHOWING DECENT RAINFALL ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS. BOTH THE ECMWF AND CANADIAN MODELS TRACK THE UPPER
LOW OUT ACROSS WESTERN AND NORTHERN TEXAS INTO ARKANSAS AND HAVE THE
BEST RAINFALL AMOUNTS CONFINED TO AREAS ALONG AND JUST NORTH OF THE
OKLAHOMA BORDER. THE CURRENT FORECAST THROUGH MONDAY LOOKS
REASONABLE WITH LIKELY POPS NEAR THE OKLAHOMA BORDER THAT DIMINISH
FARTHER NORTH AND HAVE ONLY MADE SOME MINOR ADJUSTMENTS.
GIVEN THE CLOUDY, COOL AND MOIST CONDITIONS THAT DEVELOP, HIGH
TEMPERATURES ON SUNDAY AND MONDAY WILL LIKELY NOT GET OUT OF THE 50S
IN MANY LOCATIONS ESPECIALLY ON MONDAY.
THE REMAINDER OF THE EXTENDED PERIOD SHOULD SEE DRIER AND WARMER
WEATHER RETURNING AS UPPER LEVEL RIDGING BUILDS BACK OVER THE
CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1234 PM CDT FRI APR 24 2015
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE COMMON
ACROSS SOUTHWEST KANSAS FROM MID AFTERNOON THROUGH LATE THIS
EVENING. THE GREATEST SEVERE WEATHER RISK WILL BE CONFINED TO THE
HYS TERMINAL, WHERE WE WILL GO WITH A 2-HR TEMPO GROUP OF SEVERE
THUNDERSTORMS INCLUDING HAIL, WITH FAIRLY HIGH CONFIDENCE OF
OCCURRENCE BASED ON RUN-TO-RUN CONTINUITY FROM THE HRRR MODEL OF A
SUPERCELL ALONG THE WARM FRONT. AT GCK AND DDC, THUNDERSTORMS WILL
BE IN THE VICINITY ANY TIME AFTER 21Z AND CONTINUING THROUGH MID-
EVENING, WITH THE PRECIPITATION MODE BECOMING MORE SHOWERY BY MID TO
LATE EVENING PRIOR TO ENDING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 50 79 48 62 / 60 10 10 20
GCK 48 78 48 57 / 40 10 10 30
EHA 48 79 47 68 / 20 10 10 30
LBL 49 81 48 68 / 40 10 10 30
HYS 51 73 46 58 / 60 10 20 20
P28 53 81 52 68 / 40 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...GERARD
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1235 PM CDT FRI APR 24 2015
...UPDATED AVIATION AND SHORT TERM SECTIONS...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1234 PM CDT FRI APR 24 2015
THE SHORT-FUSE SEVERE WEATHER COMPOSITE AT MIDDAY WAS SHOWING A
THREAT AREA STARTING TO DEVELOP ALONG THE SLOWLY NORTHWARD ADVANCING
WARM FRONT ACROSS WEST-CENTRAL KANSAS. SURFACE-BASED CAPE WAS
APPROACHING 1000 J/KG PER LAPS ANALYSIS AS OF 16Z. A SYNOPTIC DRY
INTRUSION/DRYLINE WILL CONTINUE TO ADVANCE NORTHEASTWARD, SHUNTING
THE SURFACE-BASED INGREDIENTS FOR SEVERE THUNDERSTORMS UP TOWARD THE
I-70 CORRIDOR. BY 21Z, THE HRRR INDICATES DEEP MOIST CONVECTION
DEVELOPING ALONG THE WARM FRONT BY 20-21Z. THERE SHOULD BE PRETTY
GOOD LOW LEVEL SHEAR ALONG THE FRONT WITH AMPLE STREAMWISE VORTICITY
TO INGEST INTO AN INCIPIENT SUPERCELL STORM. THE HRRR HAS SHOWN A
PERSISTENT LONG-TRACK UPDRAFT HELICITY SIGNAL, WHICH WOULD SUPPORT A
FAIRLY LONG-LIVED SUPERCELL THUNDERSTORM. IT CERTAINLY APPEARS THE
BEST TORNADO THREAT WILL BE UP ALONG THE FRONT ALONG THE I-70
CORRIDOR, WITH THE MOST VIGOROUS SURFACE-BASED STORMS EXITING OUR
AREA OF RESPONSIBILITY (EAST OF ELLIS AND RUSH COUNTY) BY AS SOON AS
23Z. WE WILL HAVE TO WATCH THE BENT-BACK REGION OF ENHANCED
CAPE/MOISTURE WESTWARD ALONG I-70 FOR FUTURE GROWTH OF DEEP MOIST
CONVECTION AS SOME OF THE LATEST RUNS OF THE HRRR SUGGEST. THERE
WILL LIKELY BE A LOCALIZED HEAVY RAIN RISK ALONG THE FRONT UP THERE
SHOULD THE HRRR PAN OUT. THE SHORTWAVE TROUGH WILL QUICKLY EXIT THE
SOUTHWEST KANSAS REGION BY LATE EVENING WITH SOME WESTERLY LOW LEVEL
MOMENTUM FINALLY PUSHING INTO OUR REGION ESPECIALLY AFTER 06Z
TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI APR 24 2015
MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE
RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS
A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE
A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB
TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE
MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S
IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE
OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME
NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS
BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT
WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING
UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL
MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH
EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR
PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF
ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE
MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD
COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN
HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE
OKLAHOMA BORDER.
FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO
CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS
SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY
TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS
BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST.
GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO
WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN
KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE
SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN
BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE
MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS
ALONG THE LEE OF THE ROCKIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1234 PM CDT FRI APR 24 2015
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE COMMON
ACROSS SOUTHWEST KANSAS FROM MID AFTERNOON THROUGH LATE THIS
EVENING. THE GREATEST SEVERE WEATHER RISK WILL BE CONFINED TO THE
HYS TERMINAL, WHERE WE WILL GO WITH A 2-HR TEMPO GROUP OF SEVERE
THUNDERSTORMS INCLUDING HAIL, WITH FAIRLY HIGH CONFIDENCE OF
OCCURRENCE BASED ON RUN-TO-RUN CONTINUITY FROM THE HRRR MODEL OF A
SUPERCELL ALONG THE WARM FRONT. AT GCK AND DDC, THUNDERSTORMS WILL
BE IN THE VICINITY ANY TIME AFTER 21Z AND CONTINUING THROUGH MID-
EVENING, WITH THE PRECIPITATION MODE BECOMING MORE SHOWERY BY MID TO
LATE EVENING PRIOR TO ENDING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 81 50 79 48 / 50 60 10 10
GCK 77 48 78 48 / 60 40 10 10
EHA 76 48 79 47 / 30 20 10 10
LBL 80 49 81 48 / 40 40 10 10
HYS 73 51 73 46 / 70 60 10 20
P28 82 53 81 52 / 10 40 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...BURGERT
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
507 PM CDT FRI APR 24 2015
.UPDATE...
JUST SENT OUT A QUICK UPDATE TO INCLUDE TORNADO WATCH 103 THROUGH
10 PM TONIGHT. STORMS TO DEVELOP ALONG AND SOUTH OF A BAROCLINIC
ZONE ORIENTED EAST TO WEST MAINLY ACROSS THE INTERSTATE 20
CORRIDOR. DAMAGING WINDS...HEAVY RAIN...HAIL...AND ISOLATED
TORNADOES POSSIBLE. /05/
.PREV DISCUSSION... /ISSUED 326 PM CDT FRI APR 24 2015/
DISCUSSION...
LATEST SFC ANALYSIS SHOWING A DEEPENING SFC LOW ACROSS SE CO INTO
SW KS WITH A DRYLINE ACROSS THE TX/OK PNDL INTO W TX. A SOUTHEAST
FLANKING WARM FRONT EXTENDED FROM THE SFC LOW AND SNAKED SOUTH
AND EAST INTO CENTRAL OK TO JUST SOUTH OF DFW TO NEAR TYR TO ESF.
THIS WARM FRONT HAS MOVED VERY LITTLE TODAY ACROSS S/CENTRAL LA
BUT HAS SHOWN A GREATER TENDENCY TO MOVE NORTHWARD INTO NORTH
CENTRAL TEXAS OVER THE LAST COUPLE HOURS. CLOUD COVER REMAINS VERY
THICK AND ITS THIS CLOUD COVER THAT HAS TEMPERED DAYTIME HIGH
TEMPS TODAY. ITS ALSO THIS CLOUD COVER THAT HAS NOT ALLOWED FOR
MUCH IN THE WAY OF INSTABILITY. LATEST MESOANALYSIS ONLY SHOWING
CAPE VALUES NEAR 1000J/KG ALONG AND SOUTHWEST OF THE SLOWLY
RETURNING NORTHWARD WARM FRONT.
SUPERCELL THUNDERSTORM THAT FORMED SOUTH OF OUR AREA EARLIER TODAY
FORMED ALONG THE WARM FRONT AND THE BEST UPPER LEVEL SUPPORT WHICH
IS MEAGER AT BEST...EXISTS OUT WEST WHERE TORNADO WATCH #100 WAS
JUST ISSUED FOR PORTIONS OF CENTRAL AND N TX. THE LATEST WRF
OUTPUT HAS SHOWN A TENDENCY TO LIFT THE WARM FRONT TOO FAR NORTH
AND THUS ITS SOLUTION WAS DISCOUNTED. HAVE INSTEAD GONE WITH A
MODEL BLEND OF THE HRRR FOR THE VERY SHORT TERM...FOLLOWED BY A
GFS/ECMWF BLEND BEYOND TONIGHT. HAVING SAID THAT...THE LATEST HRRR
SHOWS CONVECTION DEVELOPING RAPIDLY NEAR AND NORTH OF THE I-20
CORRIDOR OF N TX LATER THIS EVENING WITH SOME OF THESE STORMS
LIKELY EXHIBITING DISCRETE CHARACTERISTICS AS THEY MOVE EASTWARD
INTO OUR NW ZONES. SOME OF THIS STRONG/SEVERE CONVECTION COULD
EVENTUALLY MOVE ITS WAY INTO NW LA LATE THIS EVENING/OVERNIGHT BUT
THE EVENTUAL STORM MODE SHOULD BE FOR A BROKEN LINE OF STRONG TO
SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REGION...RAPIDLY
EXPANDING AND SPREADING SOUTH AND EAST THROUGH THE NIGHT. DAMAGING
WIND GUSTS...LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE TO BE
A THREAT...WITH THE TORNADIC THREAT LIKELY ORIENTED NEAR WHERE THE
WARM FRONT SETS UP LATER THIS EVENING...SOMEWHERE ACROSS NE TX
INTO WEST CENTRAL OR NORTHWEST LOUISIANA.
THE LEAD SHORTWAVE EJECTS NORTHWARD INTO THE CENTRAL PLAINS
OVERNIGHT TONIGHT WITH NEAR ZONAL FLOW IN ITS WAKE SETTING UP
ACROSS THE SOUTHERN PLAINS. THIS SHOULD RESULT IN A MUCH DRIER DAY
ON SATURDAY BUT A STRONG PRESSURE GRADIENT WILL EXIST ACROSS THE
REGION AS WELL. STRONG SOUTHWEST WINDS AND EVENTUAL SUNSHINE WILL
ALLOW FOR SFC TEMPS TO WARM WELL INTO THE 80S ON SAT AS WELL AS
SUN WITH SOME LOCATIONS LIKELY FLIRTING WITH THE 90 DEGREE MARK.
MOISTURE BEGINS TO RETURN QUICKLY BACK INTO THE REGION FROM THE
SOUTH DURING THE DAY SUNDAY INTO SUNDAY NIGHT AS YET ANOTHER UPPER
TROUGH DIGS INTO THE SOUTHWEST CONUS AND CUTS OFF ACROSS THE FOUR
CORNERS REGION LATE SUNDAY NIGHT. THIS RETURNING MOISTURE AND
INSTABILITY WILL LIKELY RESULT IN ANOTHER RISK OF STRONG TO SEVERE
THUNDERSTORMS ACROSS OUR REGION MONDAY INTO MONDAY NIGHT WITH THE
UPPER TROUGH ONLY MAKING SLOW EASTWARD PROGRESS INTO CENTRAL OK BY
TUE. THE GOOD NEWS IS BY THIS TIME...WE SHOULD BEGIN TO SEE DRY
SLOTTING ALONG THE SOUTHERN FLANK OF THE CLOSED LOW WHICH SHOULD
RESULT IN DRIER CONDITIONS TUESDAY AND ESPECIALLY WEDNESDAY
THROUGH THE END OF THE WORK WEEK AS AS UPPER LEVEL RIDGING BEGINS
TO TAKE OVER FROM THE WEST.
PRELIMS TO FOLLOW...13.
PREV DISCUSSION... /ISSUED 102 PM CDT FRI APR 24 2015/
AVIATION...
MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR
OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO
VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80
DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL
DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND
POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM
FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG
SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT
LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING
LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS
TO RETURN TO AREA BY AROUND 25/15Z.
VII
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 69 89 64 89 / 60 20 0 10
MLU 70 87 66 87 / 60 30 10 10
DEQ 62 86 51 85 / 80 10 0 10
TXK 68 87 60 85 / 80 10 0 10
ELD 68 85 60 84 / 60 20 0 10
TYR 69 89 63 88 / 60 10 0 10
GGG 68 88 63 88 / 60 10 0 10
LFK 70 89 65 89 / 60 30 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
05/05
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
326 PM CDT FRI APR 24 2015
.DISCUSSION...
LATEST SFC ANALYSIS SHOWING A DEEPENING SFC LOW ACROSS SE CO INTO
SW KS WITH A DRYLINE ACROSS THE TX/OK PNDL INTO W TX. A SOUTHEAST
FLANKING WARM FRONT EXTENDED FROM THE SFC LOW AND SNAKED SOUTH
AND EAST INTO CENTRAL OK TO JUST SOUTH OF DFW TO NEAR TYR TO ESF.
THIS WARM FRONT HAS MOVED VERY LITTLE TODAY ACROSS S/CENTRAL LA
BUT HAS SHOWN A GREATER TENDENCY TO MOVE NORTHWARD INTO NORTH
CENTRAL TEXAS OVER THE LAST COUPLE HOURS. CLOUD COVER REMAINS VERY
THICK AND ITS THIS CLOUD COVER THAT HAS TEMPERED DAYTIME HIGH
TEMPS TODAY. ITS ALSO THIS CLOUD COVER THAT HAS NOT ALLOWED FOR
MUCH IN THE WAY OF INSTABILITY. LATEST MESOANALYSIS ONLY SHOWING
CAPE VALUES NEAR 1000J/KG ALONG AND SOUTHWEST OF THE SLOWLY
RETURNING NORTHWARD WARM FRONT.
SUPERCELL THUNDERSTORM THAT FORMED SOUTH OF OUR AREA EARLIER TODAY
FORMED ALONG THE WARM FRONT AND THE BEST UPPER LEVEL SUPPORT WHICH
IS MEAGER AT BEST...EXISTS OUT WEST WHERE TORNADO WATCH #100 WAS
JUST ISSUED FOR PORTIONS OF CENTRAL AND N TX. THE LATEST WRF
OUTPUT HAS SHOWN A TENDENCY TO LIFT THE WARM FRONT TOO FAR NORTH
AND THUS ITS SOLUTION WAS DISCOUNTED. HAVE INSTEAD GONE WITH A
MODEL BLEND OF THE HRRR FOR THE VERY SHORT TERM...FOLLOWED BY A
GFS/ECMWF BLEND BEYOND TONIGHT. HAVING SAID THAT...THE LATEST HRRR
SHOWS CONVECTION DEVELOPING RAPIDLY NEAR AND NORTH OF THE I-20
CORRIDOR OF N TX LATER THIS EVENING WITH SOME OF THESE STORMS
LIKELY EXHIBITING DISCRETE CHARACTERISTICS AS THEY MOVE EASTWARD
INTO OUR NW ZONES. SOME OF THIS STRONG/SEVERE CONVECTION COULD
EVENTUALLY MOVE ITS WAY INTO NW LA LATE THIS EVENING/OVERNIGHT BUT
THE EVENTUAL STORM MODE SHOULD BE FOR A BROKEN LINE OF STRONG TO
SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REGION...RAPIDLY
EXPANDING AND SPREADING SOUTH AND EAST THROUGH THE NIGHT. DAMAGING
WIND GUSTS...LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE TO BE
A THREAT...WITH THE TORNADIC THREAT LIKELY ORIENTED NEAR WHERE THE
WARM FRONT SETS UP LATER THIS EVENING...SOMEWHERE ACROSS NE TX
INTO WEST CENTRAL OR NORTHWEST LOUISIANA.
THE LEAD SHORTWAVE EJECTS NORTHWARD INTO THE CENTRAL PLAINS
OVERNIGHT TONIGHT WITH NEAR ZONAL FLOW IN ITS WAKE SETTING UP
ACROSS THE SOUTHERN PLAINS. THIS SHOULD RESULT IN A MUCH DRIER DAY
ON SATURDAY BUT A STRONG PRESSURE GRADIENT WILL EXIST ACROSS THE
REGION AS WELL. STRONG SOUTHWEST WINDS AND EVENTUAL SUNSHINE WILL
ALLOW FOR SFC TEMPS TO WARM WELL INTO THE 80S ON SAT AS WELL AS
SUN WITH SOME LOCATIONS LIKELY FLIRTING WITH THE 90 DEGREE MARK.
MOISTURE BEGINS TO RETURN QUICKLY BACK INTO THE REGION FROM THE
SOUTH DURING THE DAY SUNDAY INTO SUNDAY NIGHT AS YET ANOTHER UPPER
TROUGH DIGS INTO THE SOUTHWEST CONUS AND CUTS OFF ACROSS THE FOUR
CORNERS REGION LATE SUNDAY NIGHT. THIS RETURNING MOISTURE AND
INSTABILITY WILL LIKELY RESULT IN ANOTHER RISK OF STRONG TO SEVERE
THUNDERSTORMS ACROSS OUR REGION MONDAY INTO MONDAY NIGHT WITH THE
UPPER TROUGH ONLY MAKING SLOW EASTWARD PROGRESS INTO CENTRAL OK BY
TUE. THE GOOD NEWS IS BY THIS TIME...WE SHOULD BEGIN TO SEE DRY
SLOTTING ALONG THE SOUTHERN FLANK OF THE CLOSED LOW WHICH SHOULD
RESULT IN DRIER CONDITIONS TUESDAY AND ESPECIALLY WEDNESDAY
THROUGH THE END OF THE WORK WEEK AS AS UPPER LEVEL RIDGING BEGINS
TO TAKE OVER FROM THE WEST.
PRELIMS TO FOLLOW...13.
&&
.PREV DISCUSSION... /ISSUED 102 PM CDT FRI APR 24 2015/
AVIATION...
MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR
OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO
VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80
DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL
DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND
POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM
FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG
SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT
LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING
LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS
TO RETURN TO AREA BY AROUND 25/15Z.
VII
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 69 89 64 89 / 60 20 0 10
MLU 70 87 66 87 / 60 30 10 10
DEQ 62 86 51 85 / 80 10 0 10
TXK 68 87 60 85 / 80 10 0 10
ELD 68 85 60 84 / 60 20 0 10
TYR 69 89 63 88 / 60 10 0 10
GGG 68 88 63 88 / 60 10 0 10
LFK 70 89 65 89 / 60 30 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
VII/13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
102 PM CDT FRI APR 24 2015
.AVIATION...
MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR
OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO
VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80
DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL
DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND
POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM
FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG
SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT
LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING
LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS
TO RETURN TO AREA BY AROUND 25/15Z./VII/.
&&
.PREV DISCUSSION... /ISSUED 1032 AM CDT FRI APR 24 2015/
DISCUSSION...
TWO AREAS OF CONCERN THIS MORNING ACROSS THE REGION...THE FIRST
BEING INCREASING COVERAGE OF THUNDERSTORMS ACROSS SOUTHEAST/EAST
CENTRAL TX AND THE SECOND BEING INCREASING COVERAGE NORTH OF THE
I-20 CORRIDOR.
THE FIRST IS DUE IN PART TO A WEAK PERTURBATION IN SW FLOW ALOFT
SWINGING NE FROM CENTRAL TX. THIS UPPER LEVEL FEATURE ALSO HAS
SOME SURFACE SUPPORT AS AN ANALYSIS SHOWS A WARM FRONT NEARLY
STAGNATED FROM N TX...SNAKING ITS WAY SOUTHEAST ACROSS THE LOWER
TOLEDO BEND RESERVOIR INTO SOUTHEAST LA. THIS WARM FRONT IS
EXPECTED TO COME SLOWLY NORTHWARD TODAY...PERHAPS AS FAR NORTH AS
THE I-20 CORRIDOR OF N LA. THE SECOND AREA OF CONCERN IS OF A MORE
ELEVATED NATURE THIS MORNING WITH COVERAGE NORTH OF THE I-20
CORRIDOR. THIS ACTIVITY IS WELL NORTH OF THE WARM FRONT BUT IS
SITUATED AGAIN WITH STRONGER PERTURBATIONS IN THE SOUTHWEST FLOW
ALOFT.
FOR THE UPDATE THIS MORNING...RAISED RAIN CHANCES WHERE THESE TWO
ENHANCED AREAS OF PRECIP WERE OBSERVED. OUR SEVERE WEATHER THREAT
FOR LATER TODAY/THIS EVENING WILL DEPEND GREATLY ON JUST HOW MUCH
WE ARE ABLE TO DESTABILIZE AND HOW FAR NORTH THE WARM FRONT MAKES
IT INTO OUR REGION FROM THE SOUTH. THE HRRR SHOWS A BREAK IN THE
WIDESPREAD ACTIVITY LATER THIS AFTN ACROSS THE SOUTHERN HALF OF NE
TX IN THE WAKE OF THE FIRST DISTURBANCE AND THIS MAY BE THE BREAK
NECESSARY FOR AT LEAST OUR SOUTHERN HALF TO WARM UP AS THIS AREA
SHOULD BE WELL INTO THE WARM SECTOR BY THIS TIME. DEEP LAYER SHEAR
IS SUPPORTIVE OF SUPERCELLS AND EVENTUAL BOWING LINE SEGMENTS IF
WE CAN GET THE INSTABILITY TO INCREASE LATER TODAY. LOW LEVEL
SHEAR WILL ALSO BE SUPPORTIVE OF A FEW TORNADOES...ESPECIALLY
ALONG AND JUST SOUTH OF THE WARM FRONT LATE THIS AFTERNOON/THIS
EVENING.
UPDATE OUT SHORTLY...13.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 75 70 89 64 / 80 80 20 0
MLU 74 71 90 64 / 70 80 30 10
DEQ 67 63 86 55 / 80 70 10 0
TXK 70 69 89 60 / 80 80 10 0
ELD 70 69 90 60 / 80 80 20 0
TYR 78 70 89 64 / 80 50 10 0
GGG 77 69 90 64 / 80 70 10 0
LFK 80 71 91 67 / 80 50 30 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 PM EDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM EDT FRI APR 24 2015
FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM
ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN
MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER
12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND
WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS
OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST
MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN.
BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS
EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR
MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON
RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL
PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF
THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING
ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO
SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY
SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING
ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A
COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL
BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND
WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S
TO MID 30S...WARMEST WEST.
MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE
BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH
WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE
INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI
BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE
LAND OF EAST HALF OF UPR MICHIGAN.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 342 PM EDT FRI APR 24 2015
SAT NIGHT AND SUN...SFC RIDGING AND DRY WEATHER IS EXPECTED TO
DOMINATE THE WRN GREAT LAKES AS A MID LEVEL RIDGE BUILDS TOWARD MN
AND NW ONTARIO AND TROUGH LINGERS FROM NRN NEW ENGLAND THROUGH THE
ERN GREAT LAKES. WITH LIGHT NE TO N LOW LEVEL FLOW...TEMPS WILL
REMAIN BELOW NORMAL...ESPECIALLY NEAR LAKE SUPERIOR WHERE HIGHS WILL
REACH ONLY INTO THE LOWER 40S. READINGS TO AROUND 50 WILL PREVAIL
OVER THE SOUTH HALF.
THE SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON
WILL BE SIMILAR TO SUN. HOWEVER...WITH THE PRES GRADIENT WEAKENING
AND A SLIGHT MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE
SEVERAL DEGREES HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR.
MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN
PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE
ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER
TX/LWR MISSISSIPPI VALLEY REGION PER 12Z RUNS OF GFS AND GEM AND
23/12Z ECMWF...RESULTING IN CONTINUED DRY WEATHER HERE. THE 24/00Z
AND 24/12Z RUNS OF THE ECMWF HAVE TRENDED STRONGER WITH THE
SHORTWAVE SHOWING A MORE AGGRESSIVE EASTWARD PROGRESSION BEFORE
DIVING THE SHORTWAVE SE. THIS SOLN MAY RESULT IN SOME LIGHT SHRA
SPREADING INTO UPPER MI TUE INTO WED MORNING. GIVEN THAT LATEST
ECMWF STILL SHOWS THE MORE AGGRESSIVE EASTWARD PROGRESSION WITH
SHORTWAVE WILL MAINTAIN SLIGHT CHC POPS FOR SHRA OVER THE CWA TUE
INTO WED. CAA IN N-NE FLOW AHEAD OF BUILDING SFC HIGH FM CANADA AS
DEPICTED BY 12Z ECMWF WL KEEP TEMPS COOLER WED INTO WED NIGHT
PROBABLY SIMILAR TO EXPECTED BELOW NORMAL READINGS THIS WEEKEND.
THU-FRI...SFC HIGH PRES BUILDS BACK OVER THE REGION AND SINCE BOTH
12Z GFS AND ECMWF HAVE TRENDED FARTHER NORTH WITH SERIES OF
SHORTWAVES MOVING ACROSS SCNTRL CANADA EXPECT GENERALLY DRY
CONDITIONS TO PREVAIL. GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS
FOR UPSTREAM MID-UPR LVL RIDGING OVER THE WRN CONUS TO BE A BIT MORE
PRONOUNCED WHICH RESULTS IN A SHARPER NW FLOW DEVELOPING INTO THE
UPPER LAKES. THIS WOULD TEMPER THE WARMUP INTO THE WRN GREAT LAKES
FOR LATE WEEK AND MAY RESULT IN TEMPS CLOSER TO NORMAL INSTEAD OF
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 119 PM EDT FRI APR 24 2015
HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3
TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL
EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE
SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT
INTO SATURDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 241 PM EDT FRI APR 24 2015
HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER
GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE
WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE
TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO
NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE
EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...VOSS
AVIATION...JLA
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
334 PM EDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM EDT FRI APR 24 2015
FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM
ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN
MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER
12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND
WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS
OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST
MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN.
BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS
EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR
MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON
RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL
PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF
THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING
ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO
SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY
SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING
ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A
COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL
BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND
WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S
TO MID 30S...WARMEST WEST.
MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE
BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH
WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE
INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI
BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE
LAND OF EAST HALF OF UPR MICHIGAN.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 334 PM EDT FRI APR 24 2015
SAT NIGHT AND SUN...SFC RIDGING AND DRY WEATHER IS EXPECTED TO
DOMINATE THE WRN GREAT LAKES AS A MID LEVEL RIDGE BUILDS TOWARD MN
AND NW ONTARIO AND TROUGH LINGERS FROM NRN NEW ENGLAND THROUGH THE
ERN GREAT LAKES. WITH LIGHT NE TO N LOW LEVEL FLOW...TEMPS WILL
REMAIN BELOW NORMAL...ESPECIALLY NEAR LAKE SUPERIOR WHERE HIGHS WILL
REACH ONLY INTO THE LOWER 40S. READINGS TO AROUND 50 WILL PREVAIL
OVER THE SOUTH HALF.
THE SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON
WILL BE SIMILAR TO SUN. HOWEVER...WITH THE PRES GRADIENT WEAKENING
AND A SLIGHT MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE
SEVERAL DEGREES HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR.
MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN
PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE
ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER
TX/LWR MISSISSIPPI VALLEY REGION PER 12Z RUNS OF GFS AND GEM AND
23/12Z ECMWF...RESULTING IN CONTINUED DRY WEATHER HERE. THE 24/00Z
AND 24/12Z RUNS OF THE ECMWF HAVE TRENDED STRONGER WITH THE
SHORTWAVE SHOWING A MORE AGGRESSIVE EASTWARD PROGRESSION BEFORE
DIVING THE SHORTWAVE SE. THIS SOLN MAY RESULT IN SOME LIGHT SHRA
SPREADING INTO UPPER MI TUE INTO WED MORNING. GIVEN THAT LATEST
ECMWF STILL SHOWS THE MORE AGGRESSIVE EASTWARD PROGRESSION WITH
SHORTWAVE WILL MAINTAIN SLIGHT CHC POPS FOR SHRA OVER THE CWA TUE
INTO WED. N-NE FLOW AHEAD OF BUILDING SFC HIGH FM CANADA WL KEEP
TEMPS COOLER WED INTO WED NIGHT SIMILAR TO EXPECTED BELOW
NORMAL READINGS THIS WEEKEND.
THU-FRI...SFC HIGH PRES BUILDS BACK OVER THE REGION AND SINCE BOTH
12Z GFS AND ECMWF HAVE TRENDED FARTHER NORTH WITH SERIES OF
SHORTWAVES MOVING ACROSS SCNTRL CANADA EXPECT GENERALLY DRY
CONDITIONS TO PREVAIL. GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS
FOR UPSTREAM MID-UPR LVL RIDGING OVER THE WRN CONUS TO BE A BIT MORE
PRONOUNCED WHICH RESULTS IN A SHARPER NW FLOW DEVELOPING INTO THE
UPPER LAKES. THIS WOULD TEMPER THE WARMUP INTO THE WRN GREAT LAKES
FOR LATE WEEK AND MAY RESULT IN TEMPS CLOSER TO NORMAL INSTEAD OF
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 119 PM EDT FRI APR 24 2015
HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3
TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL
EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE
SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT
INTO SATURDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 241 PM EDT FRI APR 24 2015
HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER
GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE
WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE
TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO
NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE
EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...VOSS
AVIATION...JLA
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
241 PM EDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM EDT FRI APR 24 2015
FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM
ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN
MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER
12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND
WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS
OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST
MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN.
BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS
EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR
MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON
RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL
PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF
THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING
ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO
SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY
SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING
ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A
COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL
BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND
WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S
TO MID 30S...WARMEST WEST.
MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE
BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH
WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE
INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI
BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE
LAND OF EAST HALF OF UPR MICHIGAN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 449 AM EDT FRI APR 24 2015
AFTER A FEW PERIODS OF MUCH NEEDED PCPN DURING THE LAST 2
WEEKS...THE PATTERN IS ONCE AGAIN BECOMING ONE THAT FAVORS DRY
WEATHER IN THE UPPER GREAT LAKES. RIDGING/POSITIVE HEIGHT ANOMALIES
DEVELOPING FROM THE UPPER MISSISSIPPI VALLEY THROUGH HUDSON BAY THIS
WEEKEND WILL REDEVELOP W TO THE ROCKIES NEXT WEEK. THIS CHANGE IN THE
UPPER LEVELS WILL TRANSLATE TO SFC HIGH PRES RIDGING S FROM HUDSON
BAY THIS WEEKEND AND THEN HIGH PRES SETTLING S THRU THE PLAINS TO THE
WRN GULF THRU THU NEXT WEEK. END RESULT IS AN OVERALL DRY PATTERN
WITH NO CHANCE FOR GULF MOISTURE TO REACH UPPER MI DURING THE LONG
TERM PORTION OF THE FCST. AS FOR TEMPS...SFC HIGH PRES RIDGING S FROM
HUDSON BAY THIS WEEKEND WILL KEEP TEMPS BLO NORMAL...ESPECIALLY
ACROSS THE N WHERE GRADIENT WINDS REMAIN OFF LAKE SUPERIOR. GRADUAL
WARMING WILL OCCUR NEXT WEEK...AND THIS WILL LEAD TO TEMPS RISING TO
ABOVE NORMAL FOR ALL OR MOST LOCATIONS BY WED/THU. HOWEVER...00Z
MODEL RUNS CAST DOUBT ON THE WARMTH MIDWEEK. MORE ON THAT LATER.
OVER THE WEEKEND...AFORMENTIONED SFC HIGH PRES RIDGING S FROM HUDSON
BAY INTO THE UPPER LAKES WILL KEEP CONDITIONS NEAR LAKE SUPERIOR ON
THE CHILLY SIDE WITH HIGH TEMPS NOT GETTING HIGHER THAN THE LOWER
40S AT BEST. SOME LAKESIDE LOCATIONS FROM THE KEWEENAW EASTWARD
WON`T GET OUT OF THE 30S ON BOTH DAYS. WELL IN THE INTERIOR...
ESTIMATED MIXING HEIGHTS ON NAM/GFS FCST SOUNDINGS SUGGEST HIGHS
SAT/SUN AROUND 50F TO THE LWR 50S. SUN MAY END UP SLIGHTLY COOLER
THAN SAT AT MANY LOCATIONS UNDER A MORE NORTHERLY WIND AS OPPOSED TO
THE MORE NORTHEASTERLY WIND ON SAT. WHILE CLOUDS WILL BE DECREASING
OVER THE W SAT...LEADING TO MOSTLY SUNNY CONDITIONS ACROSS THE AREA
IN THE AFTN...SOME MOISTURE MAY BACK IN FROM THE NE FOR SUN...
LEADING TO A LITTLE MORE CLOUD COVER AT THAT TIME. MIN TEMPS SAT
NIGHT AND SUN NIGHT WILL BE IN THE 20S IN THE INTERIOR.
SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON WILL
BE SIMILAR TO SUN. HOWEVER...WITH WEAKENING PRES GRADIENT AND SLIGHT
MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE SEVERAL DEGREES
HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR.
MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN
PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE
ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER
TX/LWR MISSISSIPPI VALLEY REGION PER 12Z ECMWF AND 00Z/12Z GEM...
RESULTING IN CONTINUED DRY WEATHER HERE. EVEN IF THE GFS WHICH
DRIVES SHORTWAVE THRU THE UPPER LAKES IS CORRECT...LACK OF MOISTURE
ADVECTION/ANTECEDANT DRY AIR MASS SUGGEST VERY LITTLE POTENTIAL OF
ANY PCPN. 00Z ECMWF HAS TRENDED STRONGER WITH A MORE EASTWARD
PROGRESSION OF SHORTWAVE BEFORE DIVING SE...RESULTING IN POTENTIAL
OF SHRA SPREADING INTO UPPER MI TUE AFTN AND NIGHT. WITH THIS THE
FIRST RUN TRENDING IN THAT DIRECTION...WILL MAINTAIN A DRY FCST FOR
NOW.
HEADING INTO WED/THU...GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS
FOR UPSTREAM RIDGING TO BE A BIT MORE PRONOUNCED...RESULTING IN
SHARPER NW FLOW DEVELOPING INTO THE UPPER LAKES. SINCE THIS HAS
OFTEN BEEN A FAVORED PATTERN OVER THE LAST FEW MONTHS...THIS TREND
IN THE 00Z MODEL RUNS MAY END UP BEING A CORRECT TREND. THIS
SUGGESTS THE WARMTH (TEMPS NEAR TO SLIGHTLY ABOVE NORMAL) REFLECTED
IN THE FCST FOR WED/THU (A RESULT OF MORE WEIGHTING FROM THE
PREVIOUS WARMER SOLUTIONS) MAY BE TOO OPTIMISTIC.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 119 PM EDT FRI APR 24 2015
HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3
TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL
EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE
SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT
INTO SATURDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 241 PM EDT FRI APR 24 2015
HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER
GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE
WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE
TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO
NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE
EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE
REGION. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...JLA
MARINE...JLA
AREA FORECAST DISCUSSION
NWS JACKSON MS
445 PM CDT FRI APR 24 2015
.DISCUSSION...MORNING CONVECTIVE COMPLEXES HAVE DIMINISHED AS THEY
HAVE MOVED EAST BUT HAVE BROUGHT SOME RAIN TO THE REGION THROUGH THIS
AFTERNOON. ADDITIONAL SHOWERS AND A FEW THUNDERSTORMS CONTINUE TO
MOVE INTO THE REGION FROM THE WEST BUT THESE ARE MUCH MORE SCATTERED.
DESPITE THE DRIER AIR THAT WAS IN PLACE ACROSS THE REGION THIS
MORNING...LOW LEVEL MOISTURE HAS RETURNED TO THE REGION WITH
DEWPOINTS ACROSS SOUTHERN AND CENTRAL SECTIONS OF THE REGION IN THE
MID TO UPPER 60S. THIS IS THANKS TO A NORTHWARD MOVING WARM FRONT
FROM THE COAST. NORTH OF THE WARM FRONT...DEWPOINTS ARE IN THE MID
50S BUT EXPECT THAT THESE SHOULD INCREASE THROUGH THE REMAINDER OF
THE EVENING AS SOME MODELS EVEN SHOW UP TO 70 DEGREE DEWPOINTS ACROSS
PORTIONS OF THE REGION. MODELS CONTINUE TO INDICATE THAT ADDITIONAL
STORMS WILL DEVELOP ACROSS THE DELTA AS THE EVENING
PROGRESSES....PARTICULARLY AFTER 8-10PM. AT THIS POINT VERTICAL
TOTALS AND DEEP LAYER SHEAR INCREASE THROUGH THE EVENING(WITH SHEAR
VALUES APPROACHING 60-70KTS) AND SHOULD BE PLENTY SUFFICIENT FOR
DAMAGING WINDS...HAIL AND TORNADOES. IT APPEARS THAT THE LATEST RUNS
OF THE HRRR MIGHT HAVE THE BEST HANDLE ON THE SITUATION AS A SMALL
AREA OF LOW PRESSURE DEVELOPS IN THE DELTA IN ASSOCIATION WITH THE
APPROACHING SQUALL LINE. IT BRINGS THE LINE THROUGH MOSTLY THE
NORTHERN SECTIONS OF MY CWA FROM ABOUT 03-10Z WITH SEVERAL LEWP
STRUCTURES AND IT DOES APPEAR THAT LOCATIONS ALONG AND NORTH OF I-20
HAVE THE GREATEST SEVERE POTENTIAL...ESPECIALLY IN THE DELTA. WE
HAVE GONE AHEAD AND UPGRADED OUR HWO PRODUCTS ESPECIALLY IN THE DELTA
WHERE A SIGNIFICANT THREAT FOR SEVERE WEATHER IS EXPECTED WITH
GREATER THAN 75MPH WINDS AND STRONG TORNADOES POSSIBLE. /28/
ON SATURDAY THE OVERNIGHT THUNDERSTORM ACTIVITY WILL LEAVE A
BOUNDARY SET UP OVER THE AREA AND THE GFS/ECMWF INDICATE AT LEAST
ISOLATED TO SCATTERED THUNDERSTORM POTENTIAL SATURDAY AFTERNOON.
WITH GOOD LAPSE RATES OF AROUND 6.5 C/KM...LARGE HAIL LOOKS LIKE IT
WILL BE THE MAIN CONCERN ALONG WITH DAMAGING WIND GUSTS. STILL CANT
COMPLETELY RULE OUT A TORNADO BUT HAIL AND WIND SHOULD BE THE MAIN
CONCERN. EXPECT ALL OF THE THUNDERSTORM POTENTIAL TO END EARLY
SATURDAY EVENING WITH CLEARING SKIES SATURDAY NIGHT AS DRIER AIR
BUILDS IN./15/
THE UPPER LEVEL PATTERN ACROSS THE CONUS LOOKS TO GET QUITE
AMPLIFIED BY SUNDAY AS THE PREVIOUS TROUGH ENERGY BRINGING INCLEMENT
WEATHER IN THE SHORT TERM BECOMES PART OF A CONSOLIDATED AND LARGE
UPPER LOW OFF THE NORTHEAST COAST AND MORE ENERGY DIGS TOWARD THE
SOUTHERN PLAINS. SHORT WAVE RIDGING IN BETWEEN THESE TROUGHS WILL BE
OVER THE LOWER MS VALLEY WITH A COLD FRONT PREVIOUSLY EXPECTED TO
COME INTO THE NORTH SUNDAY LIKELY DELAYED UNTIL LATE IN THE DAY
ACCORDING TO LATEST MODEL CONSENSUS. THIS SHOULD SPELL A VERY WARM
AND MOSTLY SUNNY SUNDAY FOR MUCH OF THE REGION WITH HIGHS IN THE MID
TO UPPER 80S.
BY LATER SUNDAY NIGHT AND ESPECIALLY MONDAY DISTURBANCES SHOULD
START EJECTING OUT OF THE APPROACHING PLAINS UPPER
LOW...UNDERCUTTING HIGH LATITUDE BLOCKING IN THE PERSISTENTLY ACTIVE
SOUTHERN BRANCH OF THE JET STREAM. LATEST MODEL SOLUTIONS ARE
HINTING IN THIS PATTERN THAT BAROCLINICITY AND INSTABILITY FOCUSED
FROM THE RED RIVER VALLEY TOWARD THE GULF COAST WILL PROVIDE A FOCUS
FOR THUNDERSTORM COMPLEXES RIDING SOUTHEAST AND BLENDED GUIDANCE IS
CATCHING ON TO THIS. MONDAY AND MONDAY NIGHT POPS ARE MOST STRONGLY
FOCUSED IN SOUTHERN (AND ESPECIALLY SOUTHWESTERN) ZONES AND IT IS
QUITE POSSIBLE POPS COULD TREND EVEN MORE WEIGHTED TOWARD THE COAST.
IT IS NOT UNTIL TUESDAY OR WEDNESDAY WHEN THE UPPER LOW SHOULD COME
OVER THE REGION AND POSITIVELY FORCE SOLID RAIN AND EMBEDDED STORM
OPPORTUNITIES ACROSS THE WHOLE OF THE LOWER MS VALLEY.
MUCH DRIER WEATHER LOOKS TO MOVE IN FOR MIDDLE OF THE WEEK INTO THE
WEEKEND AS UPPER RIDGING TAKES HOLD ONCE AGAIN. /BB/
&&
.AVIATION...AS A WARM FRONT PUSHES NORTHEAST ACROSS THE AREA LATER
TONIGHT...EXPECT INCREASING CHANCES FOR TSRA AND LOWER
CIGS...ESPECIALLY ALONG AND NORTHWEST OF THE HEZ-JAN-GTR CORRIDOR IN
THE 03Z-12Z TIME FRAME. DRIER AIR WILL BECOME TO MOVE BACK IN
SATURDAY FROM THE WEST...BUT THERE WILL BE LINGERING CHANCES FOR
TSRA ESPECIALLY IN THE HBG/PIB AREA. OTHERWISE...EXPECT VFR
CONDITIONS TO PREVAIL THROUGH THE AFTERNOON INTO THE EVENING HOURS.
/EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 70 85 67 87 / 71 40 8 7
MERIDIAN 68 84 66 86 / 66 50 11 7
VICKSBURG 70 87 66 87 / 74 26 8 9
HATTIESBURG 71 85 68 89 / 42 45 10 8
NATCHEZ 71 85 68 86 / 53 31 7 7
GREENVILLE 67 86 63 82 / 97 22 5 9
GREENWOOD 67 86 63 83 / 96 34 8 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
28/15/BB/EC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
250 PM CDT FRI APR 24 2015
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 250 PM CDT FRI APR 24 2015
THE PRIMARY FORECAST CONCERNS IN THE SHORT TERM ARE POTENTIAL FOR
SEVERE STORMS...MAINLY BEFORE 08Z...AND THEN RAIN CHANCES LINGERING
ON SATURDAY. SOME AREAS OF HEAVY RAIN ARE POSSIBLE TONIGHT.
SURFACE ANALYSIS AT MID AFTERNOON SHOWED TWO LOW PRESSURE CENTERS.
ONE WAS OVER WESTERN KANSAS AND THE OTHER WAS OVER CENTRAL SOUTH
DAKOTA. THE FIRST LOW WILL STRENGTHEN OVERNIGHT AND TRACK INTO
NORTHWEST MISSOURI BY DAYBREAK SATURDAY. MODEST LOW LEVEL MOISTURE
HAD MOVED NORTHWARD INTO THE FORECAST AREA WITH DEWPOINTS IN THE
LOWER TO MID 50S AT MANY LOCATIONS. LATEST SPC MESOSCALE ANALYSIS
SHOWED THE MIXED LAYER CAPE AXIS EXTENDING FROM CENTRAL KANSAS TO
SOUTHWEST NEBRASKA THEN INTO NORTH CENTRAL NEBRASKA. EFFECTIVE
SHEAR VALUES AS OF 19Z WERE MOSTLY LESS THAN 30 KNOTS LOCALLY.
MID LEVEL LAPSE RATES WERE MOSTLY 7.5 TO 8.5 DEGREES C PER KM.
EXPECT THAT STORMS WILL INCREASE IN COVERAGE TO OUR WEST AND SOUTH
LATER THIS AFTERNOON AND EVENING...THEN CONTINUE FOR THE OVERNIGHT.
RECENT HRRR AND RAP MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THAT.
SEVERE THREAT APPEARS TO BE MAINLY HAIL AND THAT MAINLY IN OUR
FAR SOUTHWEST COUNTIES AS STORMS LIFT/MOVE NORTHEAST FROM KANSAS.
THERE IS ALSO SOME THREAT OF HAIL WITH STORMS THAT MAY AFFECT
PARTS OF NORTHEAST NEBRASKA MAINLY BEFORE MIDNIGHT. HIGHEST
POTENTIAL FOR PCPN AMOUNTS OF AN INCH OR MORE IS ACROSS SOUTHEAST
NEBRASKA AND SOUTHWEST IOWA...BUT ALL AREAS COULD SEE LOCALLY
HEAVY RAIN.
ON SATURDAY...PCPN SHOULD DECREASE IN COVERAGE AND INTENSITY DURING
THE MORNING. SOME LIGHT SHOWERS COULD LINGER INTO THE AFTERNOON...
MAINLY IN SOUTHWEST IOWA. OTHERWISE...A WEAK RIDGE OF HIGH PRESSURE
WILL BUILD INTO THE FORECAST AREA WITH NORTHERLY WINDS. CLOUDS ARE
EXPECTED TO LIMIT HEATING...SO KEPT MOST HIGHS SATURDAY IN THE MID
50S TO LOWER 60S.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 250 PM CDT FRI APR 24 2015
THIS PERIOD SHOULD BE MAINLY DRY WITH MODERATING TEMPERATURES. A
CLOSED LOW AT 500 MB IS EXPECTED TO BE OVER THE TEXAS PANHANDLE AT
THE START OF THIS PERIOD. THIS WILL TRACK OFF TO THE NORTHEAST AND
OPEN UP THROUGH MID WEEK AS A RIDGE BUILDS IN FROM THE NORTHWEST.
THE EARLY PART OF THE WEEK MAY NOT BE COMPLETELY DRY...BUT AT THIS
TIME PCPN CHANCES SEEMED TO BE 14 PERCENT OR LESS FOR ANY GIVEN
PERIOD. HIGHS WILL START OUT IN THE 60S MONDAY/TUESDAY...THEN WARM
TO THE 70S BY THURSDAY AND POSSIBLY NEAR 80 BY FRIDAY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1217 PM CDT FRI APR 24 2015
MVFR CIGS WILL CONT THROUGH THE AFTN AT KOMA/KLNK AND WILL MOVE
INTO KOFK OVER THE NEXT COUPLE OF HOURS. DRY CONDITIONS ARE
EXPECTED THROUGH THE AFTERNOON...BUT RA CHCS WILL INCREASE THIS
EVENING FOR ALL 3 TAF SITES. KOFK MAY SEE SOME SHRA MV IN FM THE
NW FM TSRA THAT DEVELOP ALONG THE COLD FRONT IN NORTHERN NEB...BUT
WILL HOLD OFF WITH THUNDER MENTION FOR NOW THERE. KLNK/KOMA WILL
SEE ACTIVITY INCREASE FM THE SOUTH THROUGH THE EVENING AND WILL
INCLUDE SOME THUNDER AT KLNK BUT WILL LEAVE OUT OF KOMA ATTM. IFR
CONDS ARE LIKELY OVERNIGHT AS THE FRONT MOVS THRU THE SITES...
IMPROVING TO MVFR ON SAT MRNG.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS ELKO NV
326 PM PDT FRI APR 24 2015
.SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON
SATURDAY. ALSO ON SATURDAY...WINDS WILL BECOME GUSTY AND MOST
AREAS WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING
SNOW LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO
TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY. CURRENTLY...A SHORTWAVE IS
MOVING THROUGH NORTHERN NEVADA. THIS SHOWS UP NICELY ON THE WATER
VAPOR. THIS WILL CONTINUE TO SLIDE EASTWARD THROUGH THE
EVENING...DEVELOPING/MAINTAINING LIGHT TO MODERATE RAIN SHOWERS
AND AN ISOLATED THUNDERSTORM OR TWO. ANY ONE SHOWER COULD DROP
~0.25 INCHES OF RAIN. THE HRRR SHOWS CONVECTION ENDING AROUND 00Z
TO 03Z FROM WEST TO EAST.
WE WILL HAVE A BRIEF BREAK FROM SHOWERS LATER THIS EVENING...BUT
THAT WILL BE SHORT LIVED AS THE NEXT WAVE DROPS IN FROM THE
NORTHWEST. THIS TROUGH IS MUCH STRONGER AND IS NEGATIVELY TILTED.
DUE TO THE NEGATIVE TILT OF THE TROUGH...THE MODELS MAY BE A TAD
TOO QUICK WITH THE TROUGH. THEREFORE...THE HIGHEST QPF/SNOW
AMOUNTS ARE IN WHITE PINE AND NE NYE COUNTIES. ISOLATED TS WILL
AGAIN BE POSSIBLE ON SATURDAY...MAINLY EAST OF HIGHWAY 95. SNOW
LEVELS WILL START OUT ABOVE 7000FT...BUT WILL LOWER TO MOST
VALLEY FLOORS BETWEEN 5500-6500FT THROUGH THE AFTERNOON/EVENING.
SNOW LEVELS IN FAR NW NV WILL START OUT AROUND 6500FT AND LOWER
TO 5000FT BY SATURDAY EVENING. EXPECTING LITTLE...IF ANY...IMPACTS
IN THE VALLEYS. THE COLD AIR WILL BE SLOW TO ARRIVE...AND GIVEN
THE HIGH SUN ANGLE...ROADS SHOULD REMAIN WET. ANY IMPACTS WILL BE
ABOVE 6500FT...BUT WILL STILL BE MINIMAL GIVEN THE TIME OF YEAR. A
TRACE TO ONE INCH OF SNOW WILL BE POSSIBLE BELOW 6500FT...WITH
SEVERAL INCHES IN THE MOUNTAINS. SOME OF THE HIGHER ELEVATION
VALLEYS IN NORTHERN ELKO AND WHITE PINE COUNTIES COULD LOCALLY SEE
UP TO 3 INCHES. LOCALLY A FOOT OF SNOW COULD FALL IN THE HIGHEST
MTNS IN WHITE PINE AND NE NYE COUNTIES.
IN ADDITION...GUSTY NW WINDS WILL DEVELOP SATURDAY EVENING THROUGH
SUNDAY AFTERNOON. NW NYE WILL APPROACH WIND ADV CRITERIA DUE TO
PRESSURE GRADIENT/PRESSURE FALLS. MAV/MET GUIDANCE SUPPORTS STRONG
GUSTS AND THIS WILL BE MONITORED FOR AN ADV.
BY SUNDAY MORNING...MOST LOCATIONS WILL BE DRY. A WARMING TREND
WILL COMMENCE ON MONDAY...WHERE 60S/70S WILL BE PREVALENT.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. MODELS IN FAIRLY GOOD
AGREEMENT WITH THE OVERALL PATTERN THROUGH WEDNESDAY NIGHT. RIDGE
BUILDING IN FROM THE WEST MONDAY NIGHT WITH RIDGE AXIS OVER THE CWA
BY 18Z TUESDAY FOR A WARMING TREND AND DRY CONDITIONS. SHORTWAVE
PASSING TO THE NORTHWEST FLATTENS THE RIDGE A BIT BUT KEEPS WARM
SOUTHWEST FLOW OVER OUR REGION...WITH TEMPERATURES NEAR 80 DEGREES
BY WEDNESDAY. 12Z MODELS DIFFER WITH GFS NOW TRYING TO DIG A STRONG
TROF INTO NORTHERN CA WHILE THE EC MUCH WEAKER WITH THIS SHORTWAVE.
STILL...EITHER SOLUTION WOULD KEEP THE CWA DRY...BUT GFS WOULD IMPLY
WINDY CONDITIONS AND SOME INSTABILITY IN CENTRAL NV. UNTIL MODELS
COME INTO BETTER AGREEMENT...RIGHT NOW WILL LEAN TOWARD WEAKER EC
MODEL IN KEEPING THE CWA DRY WITH LESS WIND AND STABILITY.
&&
.AVIATION...RAIN SHOWERS OVER THE CWA WILL DECREASE THIS EVENING
BRIEFLY BEFORE INCREASING AGAIN AFTER 10Z AT KWMC...18Z AT KEKO
...AND 20Z AT KELY. THUS ON SATURDAY...CIGS ARE EXPECTED TO LOWER TO
AT LEAST MVFR AND PERHAPS BRIEFLY IFR AT THESE TERMINALS. WINDS WILL
BE GUSTY AT THE TERMINALS THROUGH 03Z THIS EVENING.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
94/87/87
AREA FORECAST DISCUSSION
NWS ELKO NV
1159 AM PDT FRI APR 24 2015
.SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON
SATURDAY. ALSO ON SATURDAY WINDS WILL BECOME GUSTY AND MOST AREAS
WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING SNOW
LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO
TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK.
&&
.SHORT TERM UPDATE...DECIDED TO INCLUDE SLIGHT CHANCE OF THUNDER
FOR THE REST OF THIS AFTERNOON. MARGINAL INSTABILITY AND
APPROACHING SHORTWAVE WILL PROMOTE SOME ISOLATED TS. CURRENT RADAR
TRENDS ARE SHOWING SOME ENHANCED CORES MOVING IN FROM
PERSHING/CHURCHILL COUNTIES. HRRR SHOWS THESE SHOWERS MOVING
EASTWARD THROUGHOUT THE DAY.
.PREV DISCUSSION... /ISSUED AT 322 AM /
SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON
SATURDAY. ALSO ON SATURDAY WINDS WILL BECOME GUSTY AND MOST AREAS
WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING SNOW
LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO
TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK.
SHORT TERM...TODAY THROUGH SUNDAY. TROUGH DROPPING INTO THE
PACIFIC NORTHWEST THIS MORNING WITH ASSOCIATED JET MOVING OVER
NORTHERN CALIFORNIA AND NEVADA. AS A RESULT PRECIPITATION WILL
SPREAD NORTHWEST TO SOUTHEAST ACROSS NEVADA TODAY WITH RAIN IN THE
VALLEYS AND SNOW IN THE MOUNTAINS. MANY VALLEY LOCATIONS WILL
RECEIVE A TENTH OF AN INCH OF RAIN TODAY. WEAK INSTABILITY SETS
UP ACROSS EAST-CENTRAL NEVADA THIS AFTERNOON WHICH MAY TRIGGER
SOME ISOLATED THUNDERSTORMS. BEST CHANCES FOR TS WILL BE OVER AND
NEAR GREAT BASIN PARK THIS AFTERNOON WHICH COULD ENHANCE
PRECIPITATION AMOUNTS.
THE FIRST WAVE OF MOISTURE EXITS EAST INTO UTAH THIS EVENING
FOLLOWED ALMOST IMMEDIATELY WITH ANOTHER ROUND OF MOISTURE
APPROACHING FROM THE WEST. THIS SECOND SYSTEM TONIGHT INTO
SATURDAY HAS THE POTENTIAL TO SPREAD MODERATE PRECIPITATION TO
MUCH OF THE REGION. ONE TO THREE TENTHS OF AN INCH OF QPF WILL BE
COMMON ON SATURDAY...WITH HIGHER AMOUNTS POSSIBLE. MANY OF THE
MOUNTAINS ACROSS NORTHERN AND CENTRAL NEVADA WILL ADD ANOTHER 2-6
INCHES OF SNOW ON SATURDAY. MAY NEED TO CONSIDER AN ELEVATION
BASED WINTER WEATHER ADVISORY FOR SATURDAY AS SNOW AND BLOWING
SNOW ABOVE 6500-7000 FEET MAY BE A CONCERN...ESPECIALLY WITH
RESPECT TO REDUCED VISIBILITIES ON HIGH ELEVATION SUMMITS.
SHOWER ACTIVITY EXITS INTO UTAH SATURDAY NIGHT...THIS TIME
FOLLOWED UP WITH RIDGING BUILDING IN FROM THE WEST. COLD NORTHERLY
FLOW ALOFT SUNDAY MORNING WILL RESULT IN TEMPERATURES FALLING BACK
INTO THE 20S FOR MANY LOCATIONS. IF SKIES SCATTER OUT OR CLEAR
COMPLETELY EARLY SUNDAY...SOME VALLEYS MAY SEE SOME FREEZING FOG.
NORTHERLY FLOW SUNDAY WILL KEEP HIGHS ON THE COOL SIDE...GENERALLY
UPPER 50S...WHICH WOULD BE 5-10 DEGREES BELOW NORMAL.
LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. TROUGH WILL BE EXITING
THE AREA TO OUR EAST SUNDAY NIGHT WITH RIDGE BUILDING IN FROM
THE WEST. THIS TREND WILL CONTINUE THROUGH TUESDAY WITH QUICKLY
WARMING TEMPERATURES AND SUNNY SKIES. SHORTWAVE PASSING TO THE
NORTHWEST FLATTENS THE RIDGE A BIT BUT KEEPS WARM SOUTHWEST FLOW
OVER OUR REGION...WITH TEMPERATURES NOW LOOKING LIKE THEY WILL
APPROACH OR EXCEED 80 ACROSS MUCH OF THE CWA`S VALLEYS ON
WEDNESDAY. DESPITE OUR VERY WARM LATE WINTER AND EARLY
SPRING...THIS WOULD BE THE FIRST 80 OF THE YEAR IN MOST LOCALES.
ANOTHER SHORTWAVE APPROACHING OR PASSING TO THE NORTHWEST ON
THURSDAY WOULD LIKELY KNOCK TEMPS DOWN A BIT BUT IT SHOULD REMAIN
VERY WARM AND DRY WITH THE RIDGE AXIS NOT FAR AWAY TO OUR
SOUTHEAST. RCM
AVIATION...RAIN SHOWERS WILL OVERSPREAD MUCH OF THE CWA FROM WEST
TO EAST LATE TONIGHT AND FRIDAY. NORTHERN AND WESTERN TERMINALS
SHOULD AVOID THUNDER...BUT THUNDERSTORMS MAY DEVELOP FURTHER SOUTH
AND EAST AROUND KELY AND KTPH LATER IN THE DAY. CIGS LOOK TO
LOWER TO AT LEAST MVFR AND PERHAPS BRIEFLY IFR AT THE NORTHERN
TERMINALS AS THE SHOWERS MOVE IN...BUT SHOULD STAY HIGHER FOR THE
MOST PART FURTHER SOUTH. WINDS WILL BE GUSTY BY THIS AFTERNOON AT
ALL TERMINALS WITH A FEW GUSTS UP AROUND 30 KNOTS POSSIBLE.
CONDITIONS WILL GENERALLY IMPROVE IN ALL REGARDS THIS EVENING. RCM
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
94/99
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1252 PM CDT FRI APR 24 2015
.UPDATE...
ISSUED AT 1252 PM CDT FRI APR 24 2015
IMPACT OF WAVE LIFTING ACROSS NORTHWEST IOWA AT MIDDAY HAS BEEN
TWOFOLD...FIRST TO GENERATE AS EXPECTED SCATTERED SHOWERS AND A
FEW THUNDERSTORMS MAINLY NORTHWEST IOWA INTO SOUTHWEST
MINNESOTA...AND SECOND TO BRING A GREATER DEAL OF CLEARING TO THE
WESTERN/SOUTHERN CWA.
SOME ALTERATIONS MADE TO THE CONVECTIVE TRENDS THROUGH THE DAY.
WITH SUBSIDENCE FOR THE TIME BEING SETTLING ACROSS THE CWA... HAVE
DROPPED MOST OF THE LOWER POPS IN REGION BEHIND WAVE...WHILE
INCREASING CERTAINTY A BIT AHEAD. CONCERN THEN BECOMES WITH THE
LATTER AFTERNOON...WHERE THE DESTABILIZATION FROM THE ADDED
HEATING WILL ERODE WEAK CAPPING. AT LEAST MODEST CONVERGENCE
ALONG BOUNDARY LIKELY TO POOL ENOUGH MOISTURE TO RESULT IN A
500-1200 J/KG MIXED LAYER INSTABILITY...BUT DEEPER LAYER SHEAR IS
FAIRLY WEAK DUE TO THE LACK OF ANY MID LEVEL WINDS. PERHAPS COULD
SCARE UP A PULSE MULTICELL MARGINAL SEVERE HAILER ACROSS AREAS
NEAR/WEST OF THE JAMES RIVER LATE AFTERNOON INTO EARLY
EVENING...BUT OVERALL ANY SEVERE THREAT IS MINIMAL.
TOUGH PART OF TEMPERATURE FORECAST FOR LOWER MISSOURI VALLEY IS
HOW WARM IT COULD GET PRIOR TO RETURN OF STRATUS FROM THE SOUTH
AROUND MID AFTERNOON. PUSHED READINGS UP QUITE A BIT...FROM 4 TO 7
DEGREES...BUT MAY NOT BE ENOUGH IF CAN REACH POTENTIAL INDICATED
IN RAP MODEL...WHICH IS MUCH MORE IN TUNE WITH CURRENT TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT FRI APR 24 2015
NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION
CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS
IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET
FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA.
MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE
WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS
BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO
SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH
RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR
THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH...
BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR
FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF
THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK
RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH
AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF
HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA.
AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN
THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE
WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE
OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE
SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL
MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND
LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT
IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES
REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER
MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT
ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE
THIS AFTERNOON/EVENING.
FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES
SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT
STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS
HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS
EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER
NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD
ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED
TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST
IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST
MINNESOTA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 415 AM CDT FRI APR 24 2015
ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM
NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS
NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS
AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH
EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW
NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH
DAKOTA.
MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY
FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW
POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL
CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY
IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG
ENOUGH FOR RED FLAG.
MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH
WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME
SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE.
CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE
LIMITED.
LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET
BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO
INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE
WEATHER CONCERNS LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI APR 24 2015
HAVE BROKEN OUT INTO LARGELY VFR CONDITIONS ACROSS THE AREA WITH
EXCEPTION OF AREAS OF MVFR CEILINGS AHEAD OF UPPER WAVE LIFTING
ACROSS NORTHWEST IOWA. MVFR STRATUS WILL ATTEMPT TO SPREAD BACK
NORTHWARD THROUGH EASTERN NEBRASKA TOWARD KSUX BY MID TO LATE
AFTERNOON...FIGHTING MIXING ALL THE WAY. OTHER CONCERN WILL BE
WITH POTENTIAL CONVECTIVE DEVELOPMENT VERY LATE AFTERNOON AND
EARLY EVENING NEAR SURFACE CONVERGENCE TOWARD SOUTH CENTRAL SD AND
THE LOWER TO MID JAMES VALLEY. CONVECTION WOULD LIKELY HAVE BRIEF
IFR VISIBILITY AND MVFR CEILINGS. WHILE ACKNOWLEDGE THERE IS A
SMALL THREAT AT KFSD AND KSUX...WOULD SEEM A BIT LOW PROBABILITY
AND MORE DIFFICULT TO TIME AND THUS HAVE LEFT OUT ON THIS 18Z
ISSUANCE. MORE WIDESPREAD MVFR TO IFR CEILINGS WILL DEVELOP
DURING THE EVENING AND OVERNIGHT...LINGERING THROUGH SATURDAY
MORNING AS MOIST EASTERLY FLOW INTENSIFIES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHAPMAN
SHORT TERM...JH
LONG TERM...
AVIATION...CHAPMAN
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 PM CDT FRI APR 24 2015
.TONIGHT AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
AREA OF RAIN SHOWERS EXTENDS FROM NORTH CENTRAL IOWA AND SOUTHEAST
MINNESOTA INTO SOUTH CENTRAL WISCONSIN. THIS IS IN RESPONSE TO 700
MB WARM AIR ADVECTION AND FRONTOGENESIS RESPONSE...AS WELL AS FROM
AN ADVANCING 500 MB VORTICITY MAXIMUM. THESE FEATURES SHOULD
CONTINUE TO SLIDE EAST NORTHEAST ACROSS THE AREA INTO EARLY THIS
EVENING...SPREADING LIGHT TO MODERATE RAIN SHOWERS THROUGH THE AREA.
STRENGTH OF UPWARD VERTICAL MOTION SHOULD OVERCOME DRY LOW LEVELS
BELOW 5000 FEET ABOVE GROUND LEVEL DURING THIS TIME. RAP SOUNDINGS
SHOWING WEAK ELEVATED CAPE...LITTLE TO NONE ON OTHER MODELS...SO
WILL NOT INCLUDE THUNDER MENTION.
500 MB SHORTWAVE TROUGH SLIDES EAST SOUTHEAST FROM NORTHWEST
MISSOURI TO CENTRAL ILLINOIS SATURDAY. MODELS HAVE BEEN TRENDING
SLIGHTLY SOUTHWARD WITH THE BEST UPWARD VERTICAL MOTION ASSOCIATED
WITH THE SHORTWAVE AND LOW TO MID LEVEL FRONTOGENESIS/Q VECTOR
CONVERGENCE. THUS...THE QPF SHIELD IN THE MODELS HAS TRENDED A BIT
SOUTHWARD AS WELL.
AREA FORECAST SOUNDINGS STILL SHOWING A FAIR AMOUNT OF DEEP MOISTURE
IN THE SOUTH LATER TONIGHT INTO SATURDAY...LESS SO IN THE FAR
NORTHERN COUNTIES. LOOKS TO BE A NORTH TO SOUTH GRADIENT IN THE POPS
FOR THIS SYSTEM...WITH SOME UNCERTAINTY WITH THE SYSTEM TRACK.
CONTINUED HIGH POPS IN THE SOUTHERN 2/3 OF THE AREA SATURDAY...WITH
CHANCE POPS IN THE FAR NORTH. EAST NORTHEAST WINDS ARE EXPECTED TO
GRADUALLY INCREASE IN MAGNITUDE TONIGHT...WITH GUSTY EAST NORTHEAST
WINDS SATURDAY. THIS WILL MAKE FOR A RAW DAY WITH THE RAIN. LOWS
TONIGHT WILL DROP INTO THE UPPER 30S TO AROUND 40...WITH HIGHS ONLY
IN THE 40S SATURDAY WITH THE CLOUDS AND RAIN.
.SATURDAY NIGHT THROUGH MONDAY...FORECAST CONFIDENCE HIGH.
ANY LINGERING PRECIPITATION WILL COME TO AN END SATURDAY EVENING AS
A SHORTWAVE IMPULSE AND ASSOCIATED SFC LOW TRACK EASTWARD THROUGH
THE OHIO VALLEY. UPSTREAM 500 MB HEIGHTS BEGIN RISING OVER MINNESOTA
ON SATURDAY NIGHT...WITH THE MID-LEVEL RIDGE AXIS BECOMING ORIENTED
FROM THE CENTRAL PLAINS NORTHEASTWARD INTO SOUTHERN ONTARIO BY
MONDAY. THIS WILL SUPPORT SFC RIDGING THAT BUILDS INTO THE WESTERN
GREAT LAKES AND UPPER MIDWEST REGIONS ON SUNDAY NIGHT INTO MONDAY.
LOW-LEVEL COLD ADVECTION AND NORTHEASTERLY FLOW OFF THE LAKE WILL
KEEP TEMPERATURES RELATIVELY COOL ON SUNDAY. 925 MB TEMPERATURES IN
THE 3 TO 8C RANGE SUPPORT HIGHS IN THE 50S TO NEAR 60 AWAY FROM THE
LAKESHORE. WITH NEAR NEUTRAL LOW-LEVEL THERMAL ADVECTION AND
NORTHERLY FLOW ON MONDAY EXPECT READINGS TO WARM A BIT MORE ACROSS
THE WEST. PERSISTENT EASTERLY WIND COMPONENT WILL ONCE AGAIN PREVAIL
FOR THE EASTERN CWA ON MONDAY...KEEPING THE LAKESHORE COMMUNITIES
COOLER.
.TUESDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM.
MID-LEVEL RIDGING INITIALLY OVER THE EASTERN GREAT LAKES REGION
SHIFTS EAST INTO NEW ENGLAND THROUGH WEDNESDAY AS SHORTWAVE ENERGY
ADVANCES FROM THE NORTHERN/CENTRAL PLAINS INTO THE EASTERN GREAT
LAKES AND MISSISSIPPI VALLEY REGIONS. SOME UNCERTAINTY REGARDING
SHORTWAVE EVOLUTION TUESDAY NIGHT...WITH DETERMINISTIC 00Z ECMWF
BRINGING A MORE PROGRESSIVE AND STRONGER WAVE THROUGH SOUTHERN
WISCONSIN THAN THE 06Z GFS. 12Z ECMWF RUN APPEARS SLOWER...AND
EVOLVES A CLOSED LOW OVER LAKE MICHIGAN ON WEDNESDAY. SOME LIGHT
PCPN IS POSSIBLE TUESDAY NIGHT OR WEDNESDAY...BUT OVERALL FORCING
FOR ASCENT APPEARS WEAK. WARMING 925 MB TEMPERATURES OF 9-12C
SUPPORT HIGHS POTENTIALLY REACHING WELL INTO THE 60S AWAY FROM THE
LAKE.
.THURSDAY THROUGH FRIDAY...FORECAST CONFIDENCE MEDIUM.
MID-LEVEL RIDGE AXIS SETS UP OVER THE NORTHERN PLAINS WITH WEAK SFC
RIDGING KEEPING THINGS QUIET ACROSS THE CWA FOR THURSDAY INTO FRIDAY
AFTERNOON. THEREAFTER...MODEL DIFFERENCES IN THE TIMING/STRENGTH OF
A SHORTWAVE IMPULSE PASSING THROUGH SOUTHERN CANADA SUGGEST ADDING
SLIGHT CHANCE POPS FOR AREA FRIDAY NIGHT. SOME UNCERTAINTY REGARDING
TEMPERATURES DURING THE PERIOD...AND DID NOT DEVIATE FROM MODEL
BLENDED CONSENSUS VALUES.
&&
.AVIATION/00Z TAFS/...
LIGHT TO MODERATE BAND OF RAIN SHOWERS SHOULD
CONTINUE TO MOVE EAST NORTHEAST THROUGH THE AREA THROUGH EARLY THIS
EVENING. VFR CONDITIONS SHOULD REMAIN DURING THIS TIME.
EAST/SOUTHEAST WINDS WILL BECOME EAST NORTHEAST BY MIDDLE TO LATE
EVENING...GRADUALLY INCREASING IN STRENGTH LATER TONIGHT.
A LULL IN THE SHOWER ACTIVITY SHOULD OCCUR LATER THIS EVENING AND
INTO THE OVERNIGHT HOURS...UNTIL MAIN TROUGH OF LOW PRESSURE SLIDES
EAST SOUTHEAST FROM NORTHWEST MISSOURI INTO CENTRAL ILLINOIS
SATURDAY.
AREA OF LIGHT TO MODERATE RAIN SHOULD SPREAD ACROSS TAF SITES
BETWEEN 10Z AND 14Z SATURDAY...LINGERING THROUGH THE DAY. EAST TO
EAST NORTHEAST WINDS WILL REMAIN MODERATE IN STRENGTH
SATURDAY...WITH GUSTS TO AROUND 24 KNOTS. EXPECT MAINLY MVFR
CEILINGS AND VISIBILITIES WITH THE RAIN. SOME IFR VISIBILITIES AND
CEILINGS ARE POSSIBLE TOWARD KENOSHA...REMAINING ABOVE ALTERNATE
MINIMUMS.
&&
.MARINE...
EAST NORTHEAST WINDS ARE EXPECTED TO GATHER STRENGTH TONIGHT INTO
SATURDAY...BECOMING NORTHEAST SATURDAY NIGHT. GUSTS TO 25 KNOTS ARE
EXPECTED SATURDAY INTO SATURDAY NIGHT...WITH TIGHT PRESSURE GRADIENT
FROM PASSING LOW PRESSURE TO THE SOUTH.
ONSHORE FLOW WILL BUILD WAVE HEIGHTS INTO THE 3 TO 6 FOOT RANGE FOR
THE NEARSHORE WATERS. A SMALL CRAFT ADVISORY WILL BE NEEDED FOR
SATURDAY AND SATURDAY NIGHT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM SATURDAY TO 7 AM CDT SUNDAY FOR
LMZ645-646.
SMALL CRAFT ADVISORY FROM 10 AM SATURDAY TO 7 AM CDT SUNDAY FOR
LMZ643-644.
&&
$$
TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD
SATURDAY NIGHT THROUGH FRIDAY...SPM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
222 PM CDT FRI APR 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 222 PM CDT FRI APR 24 2015
AS WAVE EJECTS OUT OF SOUTHWEST U.S. MAIN FOCUS IN SHORT TERM IS
RAIN THREAT...ESPECIALLY ON SATURDAY AS SYNOPTIC SURFACE LOW PASSES
BY TO THE SOUTH.
WEAKER INITIAL SHORT WAVE TROUGH SWINGING THROUGH AREA THIS
AFTERNOON HAS GENERATED BROAD RAIN SHIELD WITH SOME WARM AIR
ADVECTION. CONSIDERABLY DRIER AIR IN CENTRAL AND EASTERN WISCONSIN
WILL BATTLE THIS. AS FORCING SHIFTS EAST THIS EVENING...BULK OF RAIN
SHOULD END BY EARLY EVENING WITH ONLY PATCHY THREAT AFTER THAT. THIS
TREND IS SUPPORTED IN HIGH RESOLUTION MODELS AND HAVE ADJUSTED RAIN
CHANCES DOWNWARD TO ACCOUNT FOR THAT.
AS STRONGER MAIN WAVE EJECTS INTO CENTRAL U.S. TONIGHT...WITH
STRONGER...DEEPER Q-G FORCING...EXTENSIVE AREA OF RAIN AND
THUNDERSTORMS WILL FORM ACROSS PARTS OF THE CORNBELT AND MID
MISSISSIPPI RIVER VALLEY. BETTER AGREEMENT IN 24.12Z MODELS WITH HOW
FAR NORTH PRECIPITATION WILL GET WHILE SOME MODELS HAVE BEEN VERY
CONSISTENT KEEPING RAIN SOUTH OF INTERSTATE 90 CONSISTENTLY. THIS
WILL MEAN A TIGHT NORTH-SOUTH GRADIENT IN RAIN CHANCES MAINLY
SATURDAY MORNING BEFORE SYSTEM EXITS BY LATE AFTERNOON. AS SURFACE
LOW SHIFTS EAST...COULD ALSO SEE INCREASING EAST TO NORTHEAST WINDS
PICK UP DRIER AIR TO THE NORTHEAST WHICH WOULD ALSO BATTLE NORTHWARD
EXTENT OF PRECIPITATION.
HAVE TRIED TO TIGHTEN THIS RAIN THREAT GRADIENT UP WITH UP TO AN
INCH OF RAIN POSSIBLE CLOSER TO HIGHWAY 20 IN IOWA...TO NOTHING
NORTH OF INTERSTATE 90. NIL TO MINIMAL CAPE SUGGEST THUNDER THREAT
TOO LOW TO MENTION THIS FAR NORTH.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 222 PM CDT FRI APR 24 2015
SHORT TERM UPPER RIDGE WILL BUILD IN QUICKLY SATURDAY NIGHT AS RAIN
THREAT ENDS AND SKIES CLEAR OUT. THIS WILL LAST INTO EARLY NEXT WEEK
WITH QUIET WEATHER ON TAP AND WARMING TEMPERATURES...CLOSER TO
NORMALS FOR LATE APRIL.
UPPER FLOW ACROSS U.S. BECOMES FAR MORE MESSY NEXT WEEK WITH LARGE
LOW OFF OF NORTHEAST AND SPLIT FLOW DEVELOPS IN WEST. THIS COULD
LEAVE OUR REGION IN FAIRLY QUIET PATTERN BETWEEN ALL THIS. MEDIUM
RANGE GUIDANCE SUGGESTS WEAK WAVE COULD DRAG COLD FRONT INTO AREA
NEXT TUESDAY WITH MINOR RAIN THREAT BUT BESIDES THAT...MORE SIGNALS
FOR RIDGING AND NICE SPRING WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1259 PM CDT FRI APR 24 2015
INITIAL ROUND OF SHOWERS MOVING ACROSS THE AREA IN A REGION OF
SOME ISENTROPIC UP GLIDE AND FRONTOGENESIS IN THE 1000-700 MB
LAYER. THESE HAVE BEEN ABLE TO PRODUCE SOME SHORT PERIODS OF MVFR
CONDITIONS. LOOKING AT THE 24.15Z HRRR AND 24.18Z NAM...THESE
SHOWERS WILL CONTINUE TO PROGRESS NORTHEAST BUT WILL HAVE A TOUGH
TIME GETTING VERY FAR INTO WESTERN WISCONSIN WHERE DEW POINTS
HAVE REMAINED IN THE TEENS. PLAN TO SHOW TEMPO GROUPS FOR BOTH TAF
SITES THROUGH THE MIDDLE OF THE AFTERNOON WITH THE SHOWERS AROUND
AND THE POTENTIAL FOR MVFR CONDITIONS. AFTER THAT...THE FORCING
BEGINS TO REFOCUS FARTHER TO THE SOUTH WITH THE FRONTOGENESIS
FOCUSING OVER EXTREME SOUTHERN WISCONSIN INTO IOWA AS THE MAIN
SURFACE LOW TRACKS ACROSS KANSAS INTO MISSOURI. THIS SHOULD TAKE
MOST OF THE RAIN SOUTH OF BOTH TAF SITES AND WENT BACK TO JUST
VCSH FOR THE LATE AFTERNOON INTO THE EARLY EVENING. AFTER
THAT...THINK THE ACTIVITY WILL BE TO THE SOUTH AND HAVE GONE DRY
FOR THE REMAINDER OF THE PERIOD. WITH THE LOW LEVEL FLOW TURNING
MORE TO THE EAST...THIS WILL HELP TO BRING IN THE LOW LEVEL DRY
AIR WHICH SHOULD SERVE TO KEEP CEILINGS VFR ONCE THE SHOWERS ARE
OUT OF THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...SHEA
LONG TERM...SHEA
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
100 PM CDT FRI APR 24 2015
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT FRI APR 24 2015
A 500 MB LOW TROUGH IS SLATED TO MOVE NORTHEAST OUT OF THE DESERT
SOUTHWEST...MOVING ACROSS THE MID MISSISSIPPI RIVER VALLEY BY 18Z
SAT. THE TROUGH/S ASSOCIATED SFC LOW WILL HOLD WITH THE
TROUGH...MOVING FROM THE SOUTHERN PLAINS TOWARD THE OH RIVER VALLEY
BY 00Z SUN. WHILE THE HEART OF THE SYSTEM WILL STAY SOUTH...OTHER
PARTS WILL PROVIDE A GOOD SHOT AT SOME RAIN...ESPECIALLY FOR
NORTHEAST IA/SOUTHWEST WI.
FIRST...STRENGTHENING 900-800 MB FRONTOGENETIC REGION WITH A NICE
NORTH-SOUTH RUNNING SWATH OF 850 MB WARM AIR ADVECTION MOVES INTO
EASTERN MN THIS AFTERNOON...WEAKENING AS THEY MOVE INTO WESTERN WI
TONIGHT. SOME LOW LEVEL MOISTURE TRANSPORT WITH THE
THERMODYNAMICS...AND EXPECT AREAS OF SHOWERS AS A RESULT.
HOWEVER...HOW FAR EAST THESE ADVANCE IS IN QUESTION. BUFKIT
SOUNDINGS AND RH FIELDS POINT TO A LOT OF DRY AIR ACROSS
WI...ACTING AS AN INHIBITOR TO THE RAIN/S EASTWARD MARCH.
THAT...WITH WEAKENING FORCING MAKE CHANCES OVER WESTERN A BIT LESS
COMPARED TO EASTERN MN.
SECOND...AS THE SFC LOW MOVES SOUTH OF THE FORECAST AREA...ITS
DEFORMATION REGION WITH SLOPING FRONTOGENETIC LIFT WILL EXTEND
ACROSS IA AND ILL. MOISTURE WRAPS AROUND THE LOW AND THERE SHOULD BE
AMPLE SATURATION FOR A BROAD AREA OF RAIN. HOW FAR NORTH THE BEST
RAIN CHANCES EXTEND IS THE BIGGEST QUESTION...AND NAM/GFS/EC ALL
SEEM TO FAVOR THE I-90 CORRIDOR SOUTH. LOOKS REASONABLE AT THE
MOMENT. SOME SOUNDINGS SUGGEST ICE COULD BE LOST FOR A PERIOD OF
TIME OVERNIGHT...MAKING DRIZZLE MORE LIKELY. GOING TO STICK WITH
RAIN AS THE PTYPE. THIS AREA OF RAIN LOOKS MOST LIKELY SAT MORNING.
DON/T SEE MUCH OF A THUNDER THREAT AT THIS TIME...MINIMAL IF ANY
INSTABILITY...AND WHAT COULD BE THERE IS AWFULLY SKINNY. BEST
CHANCES FOR ISOLATED THUNDER WOULD BE PARTS OF SOUTHEAST
MN/NORTHEAST IA THIS AFTERNOON. CONFIDENCE LOW...SO GOING TO LEAVE
OUT OF THE FORECAST FOR THE MOMENT.
THERE COULD BE SOME SNOW IN THE NORTH...BUT CHANCES FOR PCPN ARE
MUCH LESS...AND THE SUB CLOUD LAYER IS RATHER DRY...INHIBITING ANY
PCPN TYPE FROM REACHING THE GROUND.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 245 AM CDT FRI APR 24 2015
THE GFS HAS TRENDED TOWARD THE EC/GEM SOLUTION OF BUILDING A
SHORTWAVE UPPER LEVEL RIDGE ACROSS THE REGION FOR THE END OF THE
WEEKEND. SOLUTIONS THEN FAVOR A LONG WAVE RIDGE TAKING OVER FOR NEXT
WEEK...WITH VARIOUS RIDGE RUNNERS WORKING THROUGH/ACROSS IT.
PLACEMENT AND TIMING OF THESE SHORTWAVE TROUGHS ARE DUBIOUS AT
BEST...BUT THE VARIOUS SOLUTIONS ALL POINT TO DRY FOR THE BETTER
PART OF NEXT WEEK.
WITH THE SWING BACK TO RIDGING...TEMPS SHOULD FOLLOW SUIT. EXPECTING
AT OR ABOVE NORMAL HIGHS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1259 PM CDT FRI APR 24 2015
INITIAL ROUND OF SHOWERS MOVING ACROSS THE AREA IN A REGION OF
SOME ISENTROPIC UP GLIDE AND FRONTOGENESIS IN THE 1000-700 MB
LAYER. THESE HAVE BEEN ABLE TO PRODUCE SOME SHORT PERIODS OF MVFR
CONDITIONS. LOOKING AT THE 24.15Z HRRR AND 24.18Z NAM...THESE
SHOWERS WILL CONTINUE TO PROGRESS NORTHEAST BUT WILL HAVE A TOUGH
TIME GETTING VERY FAR INTO WESTERN WISCONSIN WHERE DEW POINTS
HAVE REMAINED IN THE TEENS. PLAN TO SHOW TEMPO GROUPS FOR BOTH TAF
SITES THROUGH THE MIDDLE OF THE AFTERNOON WITH THE SHOWERS AROUND
AND THE POTENTIAL FOR MVFR CONDITIONS. AFTER THAT...THE FORCING
BEGINS TO REFOCUS FARTHER TO THE SOUTH WITH THE FRONTOGENESIS
FOCUSING OVER EXTREME SOUTHERN WISCONSIN INTO IOWA AS THE MAIN
SURFACE LOW TRACKS ACROSS KANSAS INTO MISSOURI. THIS SHOULD TAKE
MOST OF THE RAIN SOUTH OF BOTH TAF SITES AND WENT BACK TO JUST
VCSH FOR THE LATE AFTERNOON INTO THE EARLY EVENING. AFTER
THAT...THINK THE ACTIVITY WILL BE TO THE SOUTH AND HAVE GONE DRY
FOR THE REMAINDER OF THE PERIOD. WITH THE LOW LEVEL FLOW TURNING
MORE TO THE EAST...THIS WILL HELP TO BRING IN THE LOW LEVEL DRY
AIR WHICH SHOULD SERVE TO KEEP CEILINGS VFR ONCE THE SHOWERS ARE
OUT OF THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM.....RIECK
LONG TERM......RIECK
AVIATION...04
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1147 AM CDT FRI APR 24 2015
.UPDATE...
AREA OF RAIN SHOWERS CONTINUE TO DEVELOP ACROSS SOUTHERN MINNESOTA
INTO NORTH CENTRAL AND NORTHEAST IOWA. THIS IS IN RESPONSE TO 700
MB WARM AIR ADVECTION AND FRONTOGENESIS RESPONSE...AS WELL AS FROM
AN ADVANCING 500 MB VORTICITY MAXIMUM. THESE FEATURES SHOULD
CONTINUE TO SLIDE EAST NORTHEAST ACROSS THE AREA THIS AFTERNOON
AND EARLY THIS EVENING...BRINGING SOME LIGHT RAIN SHOWERS TO THE
AREA.
THE BEST SHOT WILL BE ACROSS THE SOUTHERN HALF OF THE AREA...WHERE
BETTER DEEP MOISTURE SHOULD RESIDE. DRY LOW LEVELS BELOW 5000 FEET
ABOVE GROUND LEVEL MAY LIMIT AREAL COVERAGE OF SHOWERS. WILL HAVE
TO ADJUST POPS AFTER WATCHING TRENDS WITH THESE SHOWERS OVER THE
NEXT HOUR OR SO. RAP SOUNDINGS SHOWING WEAK ELEVATED CAPE...LOWER
ON OTHER MODELS...SO WILL NOT INCLUDE THUNDER MENTION AT THIS
TIME.
EAST SOUTHEAST WINDS WILL GRADUALLY INCREASE THIS AFTERNOON...AS
WELL AS THE CLOUD COVER. HIGHS SHOULD REACH THE MIDDLE TO UPPER
50S WELL INLAND...WITH 40S NEAR LAKE MICHIGAN.
WOOD
&&
.AVIATION/18Z TAFS/...
MIDDLE LEVEL CLOUDS WILL CONTINUE TO SPREAD EAST ACROSS TAF SITES
THIS AFTERNOON...AS EAST SOUTHEAST WINDS GRADUALLY INCREASE. ON
AND OFF LIGHT RAIN SHOWERS SHOULD MOVE EAST NORTHEAST THROUGH THE
AREA LATER THIS AFTERNOON AND EARLY THIS EVENING. VFR CONDITIONS
SHOULD REMAIN DURING THIS TIME.
A LULL IN THE SHOWER ACTIVITY SHOULD OCCUR LATER THIS EVENING AND
OVERNIGHT...UNTIL MAIN TROUGH OF LOW PRESSURE SLIDES EAST
SOUTHEAST FROM IOWA INTO CENTRAL ILLINOIS LATER TONIGHT INTO
SATURDAY. AREA OF LIGHT TO MODERATE RAIN SHOULD SPREAD ACROSS TAF
SITES BY MID MORNING ON SATURDAY...LINGERING THROUGH THE DAY. EAST
TO EAST NORTHEAST WINDS WILL REMAIN MODERATE IN STRENGTH LATER
TONIGHT INTO SATURDAY. EXPECT MVFR TO SOMETIMES IFR CEILINGS AND
VISIBILITIES WITH THE RAIN...REMAINING ABOVE ALTERNATE MINIMUMS.
WOOD
&&
.MARINE...
EASTERLY WINDS CONTINUE FOR THE NEARSHORE WATERS THROUGH EARLY
SATURDAY...BEFORE BACKING NORTHEASTERLY AND INCREASING DURING THE
DAY WITH THE STRONG PRESSURE GRADIENT BETWEEN ADVANCING CENTRAL
PLAINS LOW PRESSURE SYSTEM AND SOUTHERN CANADIAN RIDGING.
ONSHORE FLOW WILL BUILD WAVE HEIGHTS INTO THE 3 TO 6 FOOT RANGE
FOR THE NEARSHORE WATERS...AND WIND GUSTS INCREASE TO 20 KNOTS OR
GREATER FROM ROUGHLY 12Z TO 23Z SATURDAY. STILL APPEARS THAT A
SMALL CRAFT ADVISORY WILL BE NEEDED FOR SATURDAY AND SATURDAY
NIGHT.
SPM
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT FRI APR 24 2015/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH.
A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND
FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL
INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE
SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN
THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE
DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB
FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE
IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH
SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM
WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER
ARRIVES BY EARLY AFTERNOON.
KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT
PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA.
THIS OCCURS AS A STRONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT
SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB
FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES
INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID
30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH.
SATURDAY... FORECAST CONFIDENCE HIGH.
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY
TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A
RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST...
ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF
VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE
DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB
FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL
BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE
CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN
SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW.
THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE
CANADIAN...ECMWF AND 06Z NAM.
THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE
THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT
WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO.
PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER
WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE
REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING.
EXPECT LOWS TO BE RIGHT AROUND FREEZING.
LONG TERM...
SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH.
RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY
WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON
THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF
LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S.
TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM.
A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME
LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH
THIS TROUGH THAN THE ECMWF... BUT THEN STALLS THE TROUGH OVER THE
NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL
SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN
TEMPERATURES.
AVIATION/12Z TAFS/...MIDDLE LEVEL CLOUDS WILL INCREASE ACROSS SRN
WI THIS AFTERNOON AND EVENING ALONG WITH SCT SHOWERS AS A SHORTWAVE
TROUGH MOVES INTO THE AREA. THE LOW LEVELS WILL REMAIN FAIRLY DRY SO
VFR CONDITIONS WILL STILL PREVAIL WITH PERHAPS MVFR VSBYS WITH ANY
HEAVIER SHOWERS THAT MAY OCCUR. THE RAIN WILL BECOME MORE WIDESPREAD
FOR SAT AM AS A STRONGER SHORTWAVE TROUGH AND LOW PRESSURE AREA
MOVES FROM THE CENTRAL GREAT PLAINS TO THE OHIO RIVER VALLEY. SAT AM
IS WHEN THE CIGS WILL DROP TO 1-3.0 KFT AND VSBYS TO 3-5SM WITH THE
WIDESPREAD MDT RAINFALL.
MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR SAT AND
SAT NT. BRISK ELY WINDS WILL DEVELOP ON SAT AS THE PRESSURE GRADIENT
TIGHTENS BETWEEN POLAR HIGH PRESSURE OVER SRN CANADA AND LOW
PRESSURE MOVING FROM THE CENTRAL GREAT PLAINS INTO THE MIDDLE MS
RIVER VALLEY. THE WINDS WILL TURN NELY FOR SAT AFT AND NIGHT AS THE
LOW TRACKS ACROSS THE OHIO RIVER VALLEY. WAVE HEIGHTS WILL BUILD TO
3 TO 5 FEET DURING THIS TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...WOOD/SPM
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
SATURDAY THROUGH THURSDAY...MRC