Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/21/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
830 PM MST FRI MAR 20 2015
.SYNOPSIS...
LINGERING SHOWERS AND THUNDERSTORMS OVER HIGHER TERRAIN LOCATIONS
WILL DISSIPATE TONIGHT. OTHERWISE...THE REGION WILL DRY OUT WITH A
RETURN OF MOSTLY CLEAR SKIES AND A DISTINCT WARMING TREND. HIGH
TEMPERATURES WILL BE IN THE 80S WITH THROUGH EARLY NEXT WEEK.
&&
.DISCUSSION...
THE PRIMARY CIRCULATION CENTER AND STRONGEST SYNOPTIC ASCENT REMAINS
WELL SOUTH OF THE FORECAST AREA THIS EVENING...HOWEVER THE
COMBINATION OF WEAKLY DIFLUENT FLOW ALOFT...MARGINALLY STEEP
MIDLEVEL LAPSE RATES AND COLD CORE...AND SFC DESTABILIZATION CREATED
AN ENVIRONMENT OVER HIGHER TERRAIN CONDUCIVE FOR PERSISTENTLY DEEP
CONVECTIVE UPDRAFTS. PER REGIONAL MESOANALYSIS...STORMS HAVE LARGELY
EXHAUSTED AVAILABLE MLCAPE...WITH THE LAST VESTIGES OF ORGANIZED
UPDRAFTS TAPPING LINGERING 0-3KM 50 J/KG INSTABILITY UNDER A GROWING
CINH BACKGROUND. AS SUCH...RADAR TRENDS HAVE CERTAINLY TAKEN A
DOWNTURN IN THE PAST HOUR AND OTHER THAN SOME LINGER SHOWERS IN THE
HIGHER TERRAIN NORTHEAST OF THE PHOENIX METRO...ONLY THE RESIDUAL
OUTFLOW BOUNDARY WILL BE LEFT FOR THE LATE EVENING HOURS.
WITH DRY AIR ALOFT REMOVED FROM THE CONVECTIVE DEBRIS...FEEL THE
CLOUD COVER OVER CNTRL ARIZONA WILL READILY EVAPORATE TONIGHT WITH
LITTLE TO NO IMPACT ON EVENTUAL LOW TEMPERATURES. THEREFORE...HAVE
ONLY ADJUSTED THE SHORT TERM HOURLY TEMPERATURE TRENDS TO ACCOUNT
FOR LEFTOVER CLOUDS...WHILE ALSO INCREASING DEWPOINTS SOMEWHAT
ABRUPTLY ACCOUNTING TO MOIST OUTFLOW INFLUENCE.
&&
.PREVIOUS DISCUSSION...
/230 PM MST FRI MAR 20 2015/
LOW PRESSURE IS CURRENTLY IN PLACE JUST OFFSHORE OF THE NORTHERN
BAJA PENINSULA. WV IMAGERY SHOWS SOME DRY AIR INTRUSION WRAPPING
INTO THE LOW BUT STILL A GOOD BELT OF MOISTURE ON THE NORTHWEST SIDE
OF THE LOW...FROM NORTHERN BAJA UP THROUGH SOUTHWEST AZ ON UP TO
NORTHWEST NM. ALSO ON WV IMAGERY SOME SIGNS OF A RIDGE BEGINNING TO
MOVE BACK INTO THE REGION WITH A DRY SLOT SHOWING FROM OVER SAN
DIEGO UP THROUGH THE LAKE MEAD...COLORADO RIVER REGION. MODELS
INDICATE THE LOW PRESSURE WILL VERY SLOWLY MOVE EASTWARD FOR ANOTHER
24 HOURS BEFORE BEING ABSORBED BY THE LARGE SCALE WESTERLIES ONCE
THE LOW REACHES WEST TEXAS LATER ON SATURDAY. BY THEN ZONAL FLOW
ALOFT WILL TAKE OVER AND BUILD BACK SOME RIDGING OVER AZ AND CA.
THIS WILL BRING A RETURN TO WARMER TEMPS AND MOSTLY CLEAR CONDITIONS
TO THE REGION. BY MID WEEK ANOTHER NEW TROUGH WILL DROP DOWN INSIDE
THE NORTHWESTERLY FLOW AND ATTEMPT TO CUTOFF ANOTHER LOW PRESSURE
SYSTEM BY THURSDAY MORNING. GFS IS RATHER AGGRESSIVELY CALLING FOR
DEVELOPMENT OF A PRONOUNCED CUT OFF LOW OFF THE BAJA PENINSULA.
CONFIDENCE LEVELS ATTM NOT THAT STRONG AS TO WHAT IMPACTS MAY BE
FELT IN OUR REGION AS THERE IS SOME DIVERGENCE IN THE VARIOUS MODEL
SOLUTIONS. SO...WE SHALL HAVE TO WAIT AND SEE IF THERE IS MUCH
CHANCE FOR CLOUDS AND OR PRECIP FOR THE REGION.
EARLY MORNING WATER VAPOR IMAGERY REVEALS LOW PRESSURE OVER THE GULF
OF CALIFORNIA...AND CONTINUES TO DEPICT A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATING AROUND THE PARENT CIRCULATION. THE LOW HAS MOVED
SOUTHWARD SINCE THURSDAY EVENING AND MOST OF SOUTHEAST CALIFORNIA
AND SOUTHWEST ARIZONA IS BEGINNING TO EXPERIENCE THE EFFECTS OF
STRONG SUBSIDENCE...BUT A FEW SHOWERS PERSIST ACROSS THE AREA /MAINLY
SOUTH-CENTRAL ARIZONA/ AS OF 0830Z. RAINFALL AMOUNTS SINCE MIDNIGHT
HAVE BEEN VERY LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OR LESS.
WITH RAIN ACROSS THE REGION ON THURSDAY AND ELEVATED DEWPOINTS IN THE
LOWER 50S...THERE REMAINS A NON-ZERO CHANCE OF FOG THROUGH THE EARLY
MORNING HOURS BUT AT THIS POINT IT APPEARS THERE IS JUST ENOUGH CLOUD
COVER AND ENOUGH BL MIXING TO PRECLUDE WIDESPREAD FOG DEVELOPMENT.
RECENT RUNS OF THE HRRR ARE HINTING AT THE POTENTIAL FOR FOG
DEVELOPMENT ACROSS THE WEST VALLEY FROM BUCKEYE INTO LA PAZ COUNTY
ALTHOUGH SATELLITE INDICATES QUITE A BIT OF CLOUD COVER. AREA WEBCAMS
ARE FOG FREE AS WELL AND I WILL KEEP THE MENTION OF FOG OUT OF THE
FORECAST.
ANOMALOUSLY HIGH ATMOSPHERIC MOISTURE /PWATS IN THE 99TH PERCENTILE
ACROSS PORTIONS OF ARIZONA/ WILL REMAIN IN PLACE TODAY AND THE
MAJORITY OF OPERATIONAL HI-RES MODELS INDICATE ANOTHER ROUND OF
SHOWERS ARE POSSIBLE THIS AFTERNOON. HI-RES WRF GUIDANCE AND HRRR
INDICATE SHOWERS WILL DEVELOP AGAIN LATE THIS MORNING INTO THE
AFTERNOON HOURS AND REMAIN CONFINED TO AREAS FROM PHOENIX EASTWARD.
AS SUCH...I REFINED POPS SLIGHTLY TO INDICATE 20 PERCENT CHANCES IN
THE METRO AND CLOSER TO 50-60 POPS AROUND GLOBE/MIAMI AND POINTS
EAST. ALSO INTRODUCED A MENTION OF THUNDER AS MLCAPES /WHILE LARGELY
UNIMPRESSIVE BY MONSOON STANDARDS/ WILL APPROACH 100-250 J/KG THIS
AFTERNOON.
THE UPPER LOW WILL SLOWLY DEPART THE AREA FRIDAY NIGHT INTO SATURDAY
WITH ZONAL FLOW SETTING UP ACROSS THE SOUTHWESTERN CONUS THIS
WEEKEND. THIS WILL ALLOW CONDITIONS TO RAPIDLY DRY OUT ON SATURDAY
/DEWPOINTS WILL FALL NOTICEABLY INTO THE LOWER 40S AND MID 30S/ WHILE
ALLOWING TEMPERATURES TO RISE BACK INTO THE UPPER 80S. THIS MORNING`S
00Z SUITE OF OPERATIONAL MODELS DON`T INDICATE A REMARKABLE RISE IN
500MB HEIGHTS /ONLY FORECAST TO REACH APPROX 578-580DM/ AND THUS I
WON`T FORECAST ANYTHING NEAR RECORD VALUES. HOWEVER...ABOVE NORMAL
TEMPS CERTAINLY LOOK LIKE A SAFE BET THROUGH THE WEEKEND INTO EARLY
NEXT WEEK.
A MID-WEEK TROUGH WILL MOVE THROUGH THE GREAT BASIN AND ARRIVE
IN SOUTHEAST CALIFORNIA/ARIZONA WEDNESDAY AFTERNOON. GIVEN ITS OVER-
LAND TRAJECTORY I WOULD EXPECT THE SYSTEM TO BE RELATIVELY MOISTURE
STARVED AND THE NAEFS SUPPORTS THE IDEA OF UNIMPRESSIVE PWATS
COINCIDENT WITH THE PASSAGE OF THE TROUGH. NONETHELESS WITH A PERIOD
OF STRONG SOUTHERLY FLOW AHEAD OF THE TROUGH AND MODEST MOISTURE
TRANSPORT...FELT IT WORTHWHILE TO INCLUDE CLIMO-LIKE POPS
WEDNESDAY/THURSDAY. IF NOTHING ELSE THE TROUGH WILL BRING IN HIGH
CLOUD COVER AND SLIGHTLY COOLER TEMPERATURES BEFORE DEPARTING THE
AREA LATE NEXT WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
EASTERLY OUTFLOW WINDS WILL WEAKEN SUBSTANTIALLY
OVERNIGHT...POTENTIALLY BECOMING VARIABLE FOR PERIODS. HOWEVER...THE
TRENDS WILL FAVOR PERSISTENT EAST WINDS THROUGH SATURDAY MORNING.
SFC WINDS SHOULD CHANGE TO THE TRADITIONAL WESTERLY DIRECTION
SOMEWHAT EARLIER THAN USUAL LATE SATURDAY MORNING/EARLY AFTERNOON.
OTHERWISE...RESIDUAL MIDLEVEL CLOUDS FROM DECAYING STORMS WILL CLEAR
BY SUNRISE SATURDAY...WITH ONLY A FEW BUILDUPS OVER HIGH TERRAIN
SATURDAY AFTERNOON.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
NO AVIATION IMPACTS THROUGH SATURDAY AFTERNOON UNDER CLEAR
SKIES. SFC WINDS WILL FAVOR A S/SW DIRECTION THOUGH WILL LIKELY BE
VARIABLE FOR PROLONGED PERIODS SATURDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
AN AREA OF LOW PRESSURE WILL EXIT TO THE EAST SATURDAY ALLOWING A
DRIER WESTERLY FLOW TO FILTER INTO THE LOWER DESERTS...LOWERING
HUMIDITY VALUES INTO THE TEENS ACROSS THE CENTRAL AND WESTERN
DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE OF SHOWERS ACROSS
THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE EAST OF GLOBE.
FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT WILL DOMINATE
THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY BUILDS ACROSS
THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH THE WARMER
LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY MONDAY...THEN
LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE NEXT 2 DAYS.
MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS BETWEEN 10 AND
15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT WEEK. RATHER LIGHT
WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY WITH WINDS INCREASING
TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE
AFTERNOON HOURS EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...MO/WATERS/LEINS
AVIATION....MO
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
220 PM MST THU MAR 19 2015
.SYNOPSIS... CLOUDY CONDITIONS WITH AREAS OF LIGHT SHOWERS WILL
PERSIST TONIGHT. A DRYING AND WARMING TREND CAN BE EXPECTED
BEGINNING FRIDAY AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...PRECIPITATION FROM THIS MORNING HAS DISSIPATED WHILE
NEW CONVECTION HAS BLOSSOMED. FOCUS HAS SHIFTED FURTHER SOUTH
TOWARDS AN UNSTABLE AREA STRETCHING FROM EASTERN YUMA INTO PINAL
COUNTY. LATEST RAP MESOANALYSIS INDICATES SBCAPES AS HIGH AS 500
J/KG IN THIS REGION. ALTHOUGH THE LATEST RUNS OF THE HRRR HAVE
FAILED TO INITIALIZE THIS CONVECTION...CONDITIONS REMAIN FAVORABLE
FOR ADDITIONAL DEVELOPMENT THROUGH LATE AFTERNOON. MODEL CONSENSUS
ALSO INDICATES ANOTHER AREA FAVORABLE FOR PRECIPITATION IS ACROSS
EASTERN MARICOPA AND SOUTHERN GILA COUNTIES AND HIGHER POPS HAVE
BEEN RETAINED IN THESE AREAS THROUGH MIDNIGHT.
&&
.PREVIOUS DISCUSSION... LATEST RAP ANALYSIS SHOWS THE CENTER OF THE
MID-TROPOSPHERIC TROUGH NEAR PUERTO PENASCO. NUMEROUS SMALL VORTICES
ARE EMBEDDED IN THE TROUGH...WHICH HELPED TO ENHANCE ASCENT AND
SHOWER ACTIVITY OVERNIGHT. HIGHEST RAIN TOTALS HAVE BEEN OBSERVED
ACROSS NORTHERN MARICOPA COUNTY...GENERALLY BETWEEN A HALF OF AN
INCH AND THREE QUARTERS OF AN INCH...THOUGH ONLY 0.01 INCHES HAS
BEEN OBSERVED AT SKY HARBOR AIRPORT. KTWC MEASURED A PWAT OF 0.77
INCHES THIS MORNING...WHICH APPEARS TO BE A RECORD MAX FOR THE DATE.
THIS EQUATES TO STANDARDIZED ANOMALIES OF 2+ ACROSS MUCH OF AZ. AT
THE SURFACE...DEWPOINTS ARE ALSO WELL ABOVE AVERAGE...GENERALLY IN
THE MID 50S ACROSS THE AREA.
GLOBAL MODELS SUGGEST LARGER SCALE FORCING FOR ASCENT WILL BE WANING
TODAY AS MUCH OF THE AREA BECOMES POSITIONED BEHIND THE EASTWARD-
ADVANCING TROUGH AXIS. HOWEVER...HI-RES GUIDANCE INCLUDING THE HRRR
SUGGEST THE AFOREMENTIONED VORTICES WILL SUPPORT ADDITIONAL SHOWER
ACTIVITY THROUGH THIS AFTERNOON...MAINLY ACROSS NORTHERN AND WESTERN
MARICOPA COUNTY. POPS WERE INCREASED IN THESE AREAS AND TEMPERATURES
WERE ALSO LOWERED A FEW DEGREES. LATEST VISIBLE SATELLITE ALSO SHOWS
SOME AREAS OF CLEARING...MAINLY ACROSS PINAL COUNTY THIS MORNING.
INSTABILITY WILL INCREASE THIS AFTERNOON ACROSS PORTIONS OF THE AREA
AND CONVECTIVE PARAMETERS ALSO SUGGEST THE POTENTIAL FOR AN ISOLATED
RUMBLE OF THUNDER.
A DRYING TREND IS THEN EXPECTED TO BEGIN TO WORK ITS WAY EASTWARD
ACROSS THE REGION THIS EVENING AS THE MAIN TROF AXIS SHIFTS SLOWLY
OFF TO THE EAST AND PWATS BEGIN TO DROP...WITH MOST OF THE SHOWER
ACTIVITY SHIFTING INTO SOUTHERN GILA COUNTY BY LATE TONIGHT. FRIDAY
WILL SEE MORE ISOLATED-SCATTERED SHOWER ACTIVITY ACROSS SOUTHERN
GILA COUNTY AS A BIT OF MOISTURE IS WRAPPED BACK WESTWARD INTO THAT
REGION. THE CLOUDS AND SHOWERS WILL HOLD TEMPERATURES WELL INTO THE
70S ACROSS THE LOWER DESERTS OF SOUTH-CENTRAL ARIZONA...WITH SOME
LOW 80S ACROSS SW AZ AND SE CA...WITH SOME MODEST WARMING ON FRIDAY
AS SKIES BEGIN TO CLEAR.
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK ISOLD TO WIDELY SCT SHOWERS WITH MID-LEVEL CIGS AS LOW AS 6 TO
8KFT WILL PREVAIL THROUGH THE AFTERNOON. WINDS GENERALLY LIGHT
THROUGH 12Z FRIDAY MORNING...BUT STILL AN OUTSIDE CHANCE OF A
THUNDERSTORM AND GUSTY WINDS THIS AFTERNOON...HOWEVER CONFIDENCE TOO
LOW AND THE COVERAGE TOO ISOLATED TO MENTION IN TAFS. STORM ACTIVITY
EXPECTED TO DWINDLE AFTER 02Z...AND SKIES BEGIN TO CLEAR OUT LATER
THIS EVENING AS UPPER LEVEL LOW MOVES SLOWLY EAST OVERNIGHT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT-BKN MID-HIGH LEVEL CLOUD DECKS WILL BEGIN TO THIN OUT LATER THIS
AFTERNOON/EVENING...WITH AN ISOLATED SHOWER LINGERING OVER THE AREA
UNTIL 01Z FRIDAY. WINDS WILL STAY RATHER LIGHT/VARIABLE OVER THE
AREA THROUGH FRIDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE
WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO
FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE
TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A
LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF
PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A
DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER
PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES
WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER
80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS
EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH
DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST
HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY
THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND
WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS
EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...HIRSCH/PERCHA
AVIATION...MEYERS
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
935 AM MST THU MAR 19 2015
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION... LATEST RAP ANALYSIS SHOWS THE CENTER OF THE MID-
TROPOSPHERIC TROUGH NEAR PUERTO PENASCO. NUMEROUS SMALL VORTICES ARE
EMBEDDED IN THE TROUGH...WHICH HELPED TO ENHANCE ASCENT AND SHOWER
ACTIVITY OVERNIGHT. HIGHEST RAIN TOTALS HAVE BEEN OBSERVED ACROSS
NORTHERN MARICOPA COUNTY...GENERALLY BETWEEN A HALF OF AN INCH AND
THREE QUARTERS OF AN INCH...THOUGH ONLY 0.01 INCHES HAS BEEN
OBSERVED AT SKY HARBOR AIRPORT. KTWC MEASURED A PWAT OF 0.77 INCHES
THIS MORNING...WHICH APPEARS TO BE A RECORD MAX FOR THE DATE. THIS
EQUATES TO STANDARDIZED ANOMALIES OF 2+ ACROSS MUCH OF AZ. AT THE
SURFACE...DEWPOINTS ARE ALSO WELL ABOVE AVERAGE...GENERALLY IN THE
MID 50S ACROSS THE AREA.
GLOBAL MODELS SUGGEST LARGER SCALE FORCING FOR ASCENT WILL BE WANING
TODAY AS MUCH OF THE AREA BECOMES POSITIONED BEHIND THE EASTWARD-
ADVANCING TROUGH AXIS. HOWEVER...HI-RES GUIDANCE INCLUDING THE HRRR
SUGGEST THE AFOREMENTIONED VORTICES WILL SUPPORT ADDITIONAL SHOWER
ACTIVITY THROUGH THIS AFTERNOON...MAINLY ACROSS NORTHERN AND WESTERN
MARICOPA COUNTY. POPS WERE INCREASED IN THESE AREAS AND TEMPERATURES
WERE ALSO LOWERED A FEW DEGREES. LATEST VISIBLE SATELLITE ALSO SHOWS
SOME AREAS OF CLEARING...MAINLY ACROSS PINAL COUNTY THIS MORNING.
INSTABILITY WILL INCREASE THIS AFTERNOON ACROSS PORTIONS OF THE AREA
AND CONVECTIVE PARAMETERS ALSO SUGGEST THE POTENTIAL FOR AN ISOLATED
RUMBLE OF THUNDER.
&&
.PREVIOUS DISCUSSION... A DRYING TREND IS THEN EXPECTED TO BEGIN TO
WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE MAIN
TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THIS AFTERNOON...
POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE THIS MORNING
AND INTO THE EARLY AFTERNOON. VERY LIGHT SHOWERS/SPRINKLES WILL
CONTINUE INTO THE AFTERNOON...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE
THAN A TRACE AND PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN
ANY WIND SHIFTS THROUGH THE EARLY AFTERNOON...THOUGH DIRECTIONS
SHOULD FAVOR AN EASTERLY COMPONENT. WINDS SHOULD RETURN TO THE WEST
BY MID TO LATE AFTERNOON. THERE IS AN OUTSIDE CHANCE OF A
THUNDERSTORM DURING THE AFTERNOON BUT CONFIDENCE TOO LOW...AND
COVERAGE TOO ISOLATED...TO MENTION THUNDER IN THE UPCOMING MORNING
TAF PACKAGE. OF COURSE SHOULD A STORM DEVELOP THE WINDS WILL BECOME
SQUIRRELY AND UNCERTAIN...AND LOCALLY GUSTY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO
SCATTER BY THIS AFTERNOON. THERE MAY BE A FEW SHOWERS AT THE TAF
SITES THROUGH LATE MORNING...BUT THREATS FOR PRECIP SHOULD BE MOSTLY
OVER AFTER 19Z. WINDS WILL STAY RATHER LIGHT/VARIABLE AT BOTH SITES
TODAY BUT WILL LIKELY FAVOR THE SOUTH AT KBLH.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY... AN AREA OF LOW PRESSURE WILL EXIT TO
THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE
LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE
CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE
OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE
EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT
WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY
BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH
THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY
MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE
NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS
BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT
WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY
WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM
THE WEST DURING THE AFTERNOON HOURS EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO/CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
325 AM MST THU MAR 19 2015
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...
TODAY TROUGH FRIDAY... A RATHER UNSETTLED PATTERN CONTINUES THIS
MORNING ACROSS OUR CWA. CURRENT RADAR AND SATELLITE IMAGERY
CONTINUES TO SHOW SCATTERED-NUMEROUS SHOWERS ACROSS MUCH OF
ARIZONA...WITH EVEN A FEW THUNDERSTORMS ACROSS SOUTHWEST
ARIZONA...WHICH HAS LIKELY BROUGHT UP TO A HALF INCH...OR EVEN A
LITTLE MORE TO A FEW ISOLATED SPOTS. THE COMPLEX UPPER LOW CENTER
THAT HAS BROUGHT US THIS WET WEATHER IS NOW CENTERED OVER EXTREME
NORTHERN BAJA...AND IS FORECAST TO MOVE SLOWLY EASTWARD JUST SOUTH
OF THE INTERNATIONAL BORDER OVER THE NEXT 48-72 HOURS. THE FOCUS OF
THE HEAVIEST RAINFALL OVER THE LAST 6-9 HOURS HAS BEEN OVER LA
PAZ...NORTHERN YUMA...AND EXTREME WESTERN MARICOPA...AS A SPOKE OF
VORTICITY ROTATES SLOWLY WESTWARD AROUND THE MAIN LOW CENTER.
LIGHTER SHOWER ARE ALSO BEING OBSERVED AT THIS TIME ACROSS THE
REMAINDER OF MARICOPA COUNTY AS WELL...BUT RAINFALL AMOUNTS OVER THE
PAST FEW HOURS IN THAT REGION HAVE BEEN PRETTY MEAGER...MAINLY IN
THE TRACE-0.05 INCH RANGE...AS THERE HAS BEEN A BIT OF
DRYSLOTING/LOSS OF VERTICAL MOTION BEHIND THE AFOMENTIONED VORTICITY
LOBE. THE LATEST HRRR AND NAM SHORT-RANGE MODELS ARE NOW INDICATING
THAT THE HEAVIEST SHOWERS WILL LIKELY CONTINUE ACROSS SOUTHWEST AZ
AND NORTHWEST MARICOPA COUNTY...AND EVEN MOVE BACK INTO PASTS OF SE
CA BETWEEN NOW AND 18Z...THEN SHIFT BACK EASTWARD INTO MARICOPA/GILA
COUNTIES BETWEEN 18-00Z AS ANOTHER WEAK SHORTWAVE/COLD POOL ROTATES
AROUND THE MAIN LOW CENTER. ISOLATED THUNDERSTORMS WILL LIKELY
DEVELOP AGAIN THIS AFTERNOON AS SOLAR HEATING AND SLIGHTLY COLDER
AIR ALOFT DESTABILIZE THE COLUMN. A DRYING TREND IS THEN EXPECTED TO
BEGIN TO WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE
MAIN TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THIS AFTERNOON...
POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE THIS MORNING
AND INTO THE EARLY AFTERNOON. VERY LIGHT SHOWERS/SPRINKLES WILL
CONTINUE INTO THE AFTERNOON...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE
THAN A TRACE AND PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN
ANY WIND SHIFTS THROUGH THE EARLY AFTERNOON...THOUGH DIRECTIONS
SHOULD FAVOR AN EASTERLY COMPONENT. WINDS SHOULD RETURN TO THE WEST
BY MID TO LATE AFTERNOON. THERE IS AN OUTSIDE CHANCE OF A
THUNDERSTORM DURING THE AFTERNOON BUT CONFIDENCE TOO LOW...AND
COVERAGE TOO ISOLATED...TO MENTION THUNDER IN THE UPCOMING MORNING
TAF PACKAGE. OF COURSE SHOULD A STORM DEVELOP THE WINDS WILL BECOME
SQUIRRELY AND UNCERTAIN...AND LOCALLY GUSTY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO
SCATTER BY THIS AFTERNOON. THERE MAY BE A FEW SHOWERS AT THE TAF
SITES THROUGH LATE MORNING...BUT THREATS FOR PRECIP SHOULD BE MOSTLY
OVER AFTER 19Z. WINDS WILL STAY RATHER LIGHT/VARIABLE AT BOTH SITES
TODAY BUT WILL LIKELY FAVOR THE SOUTH AT KBLH.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY... AN AREA OF LOW PRESSURE WILL EXIT TO
THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE
LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE
CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE
OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE
EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT
WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY
BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH
THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY
MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE
NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS
BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT
WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY
WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM
THE WEST DURING THE AFTERNOON HOURS EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
AVIATION...MO/CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
235 AM MST THU MAR 19 2015
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...
TODAY TROUGH FRIDAY... A RATHER UNSETTLED PATTERN CONTINUES THIS
MORNING ACROSS OUR CWA. CURRENT RADAR AND SATELLITE IMAGERY
CONTINUES TO SHOW SCATTERED-NUMEROUS SHOWERS ACROSS MUCH OF
ARIZONA...WITH EVEN A FEW THUNDERSTORMS ACROSS SOUTHWEST
ARIZONA...WHICH HAS LIKELY BROUGHT UP TO A HALF INCH...OR EVEN A
LITTLE MORE TO A FEW ISOLATED SPOTS. THE COMPLEX UPPER LOW CENTER
THAT HAS BROUGHT US THIS WET WEATHER IS NOW CENTERED OVER EXTREME
NORTHERN BAJA...AND IS FORECAST TO MOVE SLOWLY EASTWARD JUST SOUTH
OF THE INTERNATIONAL BORDER OVER THE NEXT 48-72 HOURS. THE FOCUS OF
THE HEAVIEST RAINFALL OVER THE LAST 6-9 HOURS HAS BEEN OVER LA
PAZ...NORTHERN YUMA...AND EXTREME WESTERN MARICOPA...AS A SPOKE OF
VORTICITY ROTATES SLOWLY WESTWARD AROUND THE MAIN LOW CENTER.
LIGHTER SHOWER ARE ALSO BEING OBSERVED AT THIS TIME ACROSS THE
REMAINDER OF MARICOPA COUNTY AS WELL...BUT RAINFALL AMOUNTS OVER THE
PAST FEW HOURS IN THAT REGION HAVE BEEN PRETTY MEAGER...MAINLY IN
THE TRACE-0.05 INCH RANGE...AS THERE HAS BEEN A BIT OF
DRYSLOTING/LOSS OF VERTICAL MOTION BEHIND THE AFOMENTIONED VORTICITY
LOBE. THE LATEST HRRR AND NAM SHORT-RANGE MODELS ARE NOW INDICATING
THAT THE HEAVIEST SHOWERS WILL LIKELY CONTINUE ACROSS SOUTHWEST AZ
AND NORTHWEST MARICOPA COUNTY...AND EVEN MOVE BACK INTO PASTS OF SE
CA BETWEEN NOW AND 18Z...THEN SHIFT BACK EASTWARD INTO MARICOPA/GILA
COUNTIES BETWEEN 18-00Z AS ANOTHER WEAK SHORTWAVE/COLD POOL ROTATES
AROUND THE MAIN LOW CENTER. ISOLATED THUNDERSTORMS WILL LIKELY
DEVELOP AGAIN THIS AFTERNOON AS SOLAR HEATING AND SLIGHTLY COLDER
AIR ALOFT DESTABILIZE THE COLUMN. A DRYING TREND IS THEN EXPECTED TO
BEGIN TO WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE
MAIN TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THURSDAY
AFTERNOON...POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE
THURSDAY MORNING. VERY LIGHT SHOWERS/SPRINKLES WILL CONTINUE INTO
THE NIGHT...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE THAN A TRACE AND
PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN ANY WIND SHIFTS
THROUGH THURSDAY MORNING...THOUGH DIRECTIONS SHOULD FAVOR AN
EASTERLY COMPONENT.
MORE SCATTERED SHOWERS AND POTENTIALLY A FEW ISOLATED THUNDERSTORMS
WILL BE POSSIBLE THURSDAY AFTERNOON. GUSTY WIND SHIFTS MAY ACCOMPANY
ANY STORMS...WHICH WOULD BE MOST LIKELY AFTER 20Z. HAVE NOT INCLUDED
THUNDER MENTION IN TAFS GIVEN THE UNCERTAIN COVERAGE AT THIS TIME.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO SCATTER
THURSDAY AFTERNOON. SHOWERS WILL BE MOST PREVALENT AT KBLH TONIGHT
CAUSING SHIFTING WINDS...LOWERING CIGS POTENTIALLY DOWN TO 6K
FT...AND POSSIBLY BRIEF PERIODS OF LOWER VISIBILITIES. CONFIDENCE IS
LOW THAT FLIGHT CATEGORIES WOULD BE REDUCED...THOUGH NOT OUT OF THE
REALM OF POSSIBILITY. SHOWERS MAY BE POSSIBLE AGAIN FOR A SHORT
PERIOD THURSDAY AFTERNOON...THOUGH CONDITIONS SHOULD RAPIDLY IMPROVE
BY SUNSET.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...A DRYING TREND IS EXPECTED THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. EXPECT MINIMUM HUMIDITY LEVELS TO DROP
INTO THE LOWER TEENS OVER THE WEEKEND UNDER MOSTLY SUNNY SKIES.
LINGERING ISOLATED SHOWERS ARE POSSIBLE OVER THE HIGH TERRAIN EAST
OF PHOENIX THROUGH SATURDAY...BUT TEMPERATURES WILL STEADILY CLIMB
DURING THE PERIOD WITH THE WARMER DESERTS REACHING THE UPPER 80 TO
AROUND 90S BY EARLY NEXT WEEK. NO SIGNIFICANT WIND IS EXPECTED
THROUGH MONDAY...JUST SOME AFTERNOON UPSLOPE GUSTS FAVORING THE WEST
EACH DAY. INCREASING WEST WIND IS LIKELY TUESDAY WITH GUSTS IN
EXCESS OF 25 MPH POSSIBLE.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...CB/MEYERS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
230 AM MST THU MAR 19 2015
.SYNOPSIS...SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BE AROUND
THROUGH FRIDAY EVENING. DRY CONDITIONS WILL RETURN THIS WEEKEND
EXCEPT FOR A FEW LINGERING SHOWERS ACROSS THE WHITE MOUNTAINS
SATURDAY. COOLER DAYTIME TEMPERATURES TODAY AND FRIDAY THEN A
WARMING TREND THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...WIDESPREAD RAIN YESTERDAY WITH AMOUNTS RANGING FROM
0.01" TO 0.90". THIS WET WEATHER IS FORECAST TO CONTINUE TODAY INTO
FRIDAY BEFORE TURNING DRY FOR THE WEEKEND INTO NEXT WEEK.
AT 2 AM...DOPPLER RADAR SHOWED ISOLATED LIGHT SHOWERS EAST OF TUCSON
AND UP TOWARD PHOENIX. THE REST OF THE AREA WAS DRY AS SHORT WAVE
MOVES NORTH INTO CENTRAL AZ. OVERALL THE MAIN UPPER LEVEL TROF IS
STILL TO OUR WEST AND WILL SLOWLY MOVE EAST TODAY INTO FRIDAY
KEEPING SHOWER ACTIVITY GOING NEXT COUPLE OF DAYS. FOR THE SHORT
TERM A FEW THUNDERSTORMS DEVELOPED BETWEEN MIDNIGHT AND 1 AM NEAR
HERMOSILLO SONORA AND THE LATEST HRRR RUNS CAPTURED THIS NICELY AND
SPREAD THESE STORMS NNE TOWARD COCHISE COUNTY. RAINFALL AMOUNTS THRU
FRIDAY AFTERNOON ARE FORECAST TO RANGE BETWEEN 0.05" TO 0.50" IN THE
VALLEYS TO NEAR 1" IN THE MOUNTAINS. SNOW LEVEL WILL MOSTLY REMAIN
ABOVE THE TIPS BUT OCCASIONALLY FALL DOWN TO 9000 FEET. HIGH TODAY
AND FRIDAY WILL BE AT OR SLIGHTLY BELOW NORMAL.
A FEW LINGERING SHOWERS FAR EASTERN AREAS SATURDAY AS HIGH PRESSURE
BUILDS IN FROM THE WEST. FLAT RIDGE OVER THE AREA SUNDAY THROUGH
NEXT WEDNESDAY RESULTING IN A WARMING TREND.
&&
.AVIATION...VALID THRU 20/12Z.
BKN-OVC CLOUDS AT 6-10K FT AGL AND ISOLD-SCT -SHRA/-TSRA THRU THE
FORECAST PERIOD. BRIEF MVFR CONDITIONS POSSIBLE WITH THE STRONGEST
-SHRA/-TSRA...HOWEVER MOST LOCATIONS WILL HAVE VFR CONDITIONS.
SURFACE WIND LESS THAN 10 KTS THRU 19/18Z AND AGAIN AFT 20/02Z.
SURFACE WIND BETWEEN 19/18Z AND 20/02Z...WLY/NWLY AT 8-15 KTS. GUSTY
WINDS POSSIBLE NEAR THUNDERSTORMS...WITH GUSTS TO NEAR 35 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AN AREA OF LOW PRESSURE OVER THE NORTHERN BAJA
PENINSULA WILL MOVE SLOWLY EAST ACROSS THE REGION TODAY AND
FRIDAY...PUSHING EAST OF THE AREA SATURDAY. THIS SYSTEM WILL RESULT
IN A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF SOUTHEAST
ARIZONA TODAY...ACROSS THE EASTERN HALF OF SOUTHEAST ARIZONA ON
FRIDAY...AND MAINLY IN THE WHITE MOUNTAINS SATURDAY. DRY CONDITIONS
WILL THEN RETURN LATE THIS WEEKEND AND CONTINUE INTO THE MIDDLE OF
NEXT WEEK. GUSTY AND ERRATIC WINDS MAY OCCUR NEAR THUNDERSTORMS.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
127 PM PDT THU MAR 19 2015
.SYNOPSIS...
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN BAJA MAY BRING A
FEW ADDITIONAL SHOWERS AND THUNDERSTORMS THIS AFTERNOON INTO EARLY
EVENING...MAINLY FOR THE INLAND VALLEYS AND MOUNTAINS OF SAN DIEGO
COUNTY. HIGHER PRESSURE ALOFT WILL BRING DRY...WARMER WEATHER FRIDAY
THROUGH MONDAY...WITH DAY-TIME HIGHS SEVERAL DEGREES ABOVE NORMAL.
NIGHT AND MORNING MARINE LAYER STRATUS WILL CONTINUE OVER THE COAST
AND PORTIONS OF THE VALLEYS. SOME OFFSHORE FLOW AND MORE WARMING IS
POSSIBLE BY MID NEXT WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...
AN UPPER LEVEL LOW...CURRENTLY SOUTH OF THE BORDER ACCORDING TO
WATER VAPOR SATELLITE...WILL CONTINUE TO MOVE TO THE SOUTH AND EAST
THROUGH FRIDAY. BEFORE IT LEAVES...SOME LINGERING MOISTURE AND
INSTABILITY COULD BRING ANOTHER ROUND OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS TODAY. RADAR DOES NOT SHOW MUCH OVER OUR AREA
AT THE MOMENT...WITH THE NEAREST SHOWERS SOUTH OF THE BORDER AND
OVER IMPERIAL COUNTY. THE SHOWERS ARE MOVING TO THE SOUTHWEST DUE TO
THE NORTHEAST FLOW ALOFT. CURRENT GPS PRECIPITABLE WATER SENSORS
OVER THE REGION CONTINUE TO INDICATE ABOUT 0.8 TO 0.9 INCHES OF
PRECIPITABLE WATER...WHICH IS ENOUGH MOISTURE FOR
PRECIPITATION...AND THE LATEST SPC MESOANALYSIS INDICATES 500 J/KG
OF MOST UNSTABLE CAPE OVER THE AREA. ALSO...THE HRRR CONTINUES TO
SHOW THE SAN DIEGO COUNTY VALLEYS GETTING SOME HEAVY SHOWERS AND
THUNDERSTORMS FOR A FEW HOURS DURING THE MID TO LATE AFTERNOON HOURS
TODAY DUE TO DAY-TIME SURFACE HEATING AND A POSSIBLE UPPER WAVE
MOVING THROUGH. THUS...THE POTENTIAL REMAINS FOR SOME HEAVY SHOWERS
AND THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO EARLY
EVENING...WITH SAN DIEGO COUNTY LOOKING LIKE THE AREA WITH THE
BIGGEST THREAT.
TONIGHT INTO FRIDAY...AS THE LOW MOVES FARTHER FROM THE AREA TO THE
SOUTHEAST MUCH DRIER AIR MOVES IN OVER THE AREA BRINGING AN END TO
THE SHOWER/THUNDERSTORMS. THE MARINE LAYER SHOULD REMAIN
ESTABLISHED...WITH STRATUS LIKELY MOVING INTO THE COAST AND VALLEYS
AGAIN. TEMPERATURE LOOK TO BE SEVERAL DEGREES HIGHER ON FRIDAY DUE
TO CLEARING SKIES AND A RIDGE WHICH STARTS TO BUILD OVER THE AREA.
WEATHER CONDITIONS WILL BE SIMILAR SATURDAY THROUGH MONDAY WITH WEAK
RIDGING ALOFT...ONSHORE FLOW AT THE SURFACE...NIGHT AND MORNING
MARINE LAYER STRATUS MOVING INTO THE COAST AND WESTERN VALLEY
AREAS...AND TEMPERATURES SEVERAL DEGREES ABOVE NORMAL. A TROUGH
MOVING INTO THE PACIFIC NORTHWEST LATE MONDAY INTO EARLY TUESDAY
LOOKS TO BRING SOME STRONGER ONSHORE FLOW...AND SOME GUSTY WEST
WINDS TO THE MOUNTAINS AND DESERTS.
SLIGHTLY COOLER CONDITIONS WILL PREVAIL TUESDAY WITH WEAK OFFSHORE
FLOW STARTING TO DEVELOP. WEDNESDAY INTO THURSDAY...A WEAK AND DRY
TROUGH WILL MOVE OVER SOUTHERN CALIFORNIA...AND THERE IS THE
POTENTIAL FOR SOME MODERATE OFFSHORE FLOW AND INCREASED WARMING.
THIS WOULD ERADICATE THE MARINE LAYER.
&&
.AVIATION...
192000...VFR CONDITIONS FORECAST FOR MOST AREAS THROUGH LATE THIS
AFTERNOON. -SHRA/-TSRA WILL BE POSSIBLE THROUGH EARLY THIS
EVENING...MAINLY OVER INLAND AREAS. SMALL HAIL...REDUCED VIS FROM
RAIN...FREQUENT LIGHTNING AND STRONG UP/DOWN DRAFTS WILL BE POSSIBLE
NEAR STORMS. MARINE LAYER STRATUS...WITH BASES NEAR 1500 FT MSL AND
TOPS TO 2500 FT MSL...WILL REDEVELOP ALONG THE COAST THIS EVENING
AND PUSH AROUND 15-30 SM INLAND BY EARLY FRIDAY MORNING. VIS OF 3-5
SM BR WILL BE POSSIBLE WHERE STRATUS NEARS HIGHER TERRAIN. LOW
CLOUDS WILL CLEAR TOWARDS THE COAST BY LATE FRIDAY MORNING.
&&
.MARINE...
100 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SUNDAY.
BREEZY NORTHWEST WINDS WILL DEVELOP LATE MONDAY OVER THE OUTER
COASTAL WATERS...WITH GUSTS TO 20-25 KT POSSIBLE.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE...JJT
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
852 AM PDT THU MAR 19 2015
.SYNOPSIS...
UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN BAJA WILL BRING A FEW
ADDITIONAL SHOWERS AND THUNDERSTORMS THIS AFTERNOON...MAINLY FOR THE
INLAND VALLEYS AND MOUNTAINS. HIGHER PRESSURE ALOFT WILL BRING
DRY...WARMER WEATHER FRIDAY THROUGH MONDAY...WITH DAY-TIME HIGHS
SEVERAL DEGREES ABOVE NORMAL. NIGHT AND MORNING MARINE LAYER STRATUS
WILL CONTINUE OVER THE COAST AND PORTIONS OF THE VALLEYS. SOME
OFFSHORE FLOW AND MORE WARMING IS POSSIBLE BY MID NEXT WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...
AN UPPER LEVEL LOW...CURRENTLY SOUTH OF THE BORDER ACCORDING TO
WATER VAPOR SATELLITE...WILL CONTINUE TO MOVE TO THE SOUTH AND EAST
THROUGH FRIDAY. BEFORE IT LEAVES...SOME LINGERING MOISTURE AND
INSTABILITY COULD BRING ANOTHER ROUND OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS TODAY...MAINLY TO THE MOUNTAINS AND VALLEYS.
RADAR CURRENTLY SHOWS MOST OF THE SHOWER ACTIVITY OCCURRING OVER
ARIZONA...WITH SOME LIGHT SHOWERS/SPRINKLES MOVING NORTHEAST TO
SOUTHWEST OVER THE SAN BERNARDINO COUNTY MOUNTAINS AND RIVERSIDE
COUNTY. CURRENT GPS PRECIPITABLE WATER SENSORS OVER THE REGION
INDICATE ABOUT 0.8 TO 0.9 INCHES OF PRECIPITABLE WATER...WHICH IS
ENOUGH MOISTURE FOR PRECIPITATION. THE 12Z HRRR SHOWS THE SAN DIEGO
COUNTY VALLEYS GETTING SOME HEAVY SHOWERS AND THUNDERSTORMS FOR A
FEW HOURS DURING THE MID TO LATE AFTERNOON HOURS TODAY DUE TO DAY-
TIME SURFACE HEATING. MEANWHILE...VISIBLE SATELLITE SHOWS PATCHY
MARINE LAYER STRATUS OVER THE VALLEYS THIS MORNING...WHILE
INTERESTINGLY ENOUGH THE COASTAL AREAS ARE PRETTY MUCH DEVOID OF
STRATUS. ANY LOW LEVEL STRATUS LIKELY WILL CLEAR OUT BY LATE
MORNING.
TONIGHT INTO FRIDAY...AS THE LOW MOVES FARTHER FROM THE AREA TO THE
SOUTHEAST MUCH DRIER AIR MOVES IN OVER THE AREA BRINGING AN END TO
THE SHOWER/THUNDERSTORMS. THE MARINE LAYER SHOULD REMAIN
ESTABLISHED...WITH STRATUS LIKELY MOVING INTO THE COAST AND VALLEYS
AGAIN. TEMPERATURE LOOK TO BE SEVERAL DEGREES HIGHER ON FRIDAY DUE
TO CLEARING SKIES AND A RIDGE WHICH STARTS TO BUILD OVER THE AREA.
WEATHER CONDITIONS WILL BE SIMILAR SATURDAY THROUGH MONDAY WITH WEAK
RIDGING ALOFT...ONSHORE FLOW AT THE SURFACE...NIGHT AND MORNING
MARINE LAYER STRATUS MOVING INTO THE COAST AND WESTERN VALLEY
AREAS...AND TEMPERATURES SEVERAL DEGREES ABOVE NORMAL. A TROUGH
MOVING INTO THE PACIFIC NORTHWEST LATE MONDAY INTO EARLY TUESDAY
LOOKS TO BRING SOME STRONGER ONSHORE FLOW...AND SOME GUSTY WEST
WINDS TO THE MOUNTAINS AND DESERTS.
SLIGHTLY COOLER CONDITIONS WILL PREVAIL TUESDAY WITH WEAK OFFSHORE
FLOW STARTING TO DEVELOP. WEDNESDAY INTO THURSDAY...A WEAK AND DRY
TROUGH WILL MOVE OVER SOUTHERN CALIFORNIA...AND THERE IS THE
POTENTIAL FOR SOME MODERATE OFFSHORE FLOW AND INCREASED WARMING.
THIS WOULD ERADICATE THE MARINE LAYER.
&&
.AVIATION... 191530Z...PATCHY STRATUS OVER THE COAST/VALLEYS...WITH
BASES AROUND 2300 FT MSL AND TOPS TO 3200 FT MSL...WILL SLOWLY CLEAR
THIS MORNING. VIS OF 3-6 SM HZ IN THE INLAND EMPIRE WILL IMPROVE TO
P6SM BY LATE THIS MORNING. -SHRA/-TSRA WILL BE POSSIBLE THROUGH
EARLY THIS EVENING...MAINLY OVER INLAND AREAS. SMALL HAIL...REDUCED
VIS FROM RAIN...FREQUENT LIGHTNING AND STRONG UP/DOWN DRAFTS WILL BE
POSSIBLE NEAR STORMS.
MARINE LAYER STRATUS...WITH BASES NEAR 1500 FT MSL AND TOPS TO 2500
FT MSL...WILL REDEVELOP ALONG THE COAST THIS EVENING AND PUSH AROUND
15-30 SM INLAND BY EARLY FRIDAY MORNING. VIS OF 3-5 SM BR WILL BE
POSSIBLE WHERE STRATUS NEARS HIGHER TERRAIN. LOW CLOUDS MAY LIFT 200-
400 FT OVERNIGHT DUE TO A COASTAL EDDY.
&&
.MARINE... 830 AM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH
SUNDAY. BREEZY NORTHWEST WINDS WILL DEVELOP LATE MONDAY OVER THE
OUTER COASTAL WATERS...WITH GUSTS TO 20-25 KT POSSIBLE.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE...JJT
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1040 PM PDT WED MAR 18 2015
.UPDATE...REMOVED SHOWERS FROM THE SIERRA ZONES FOR TONIGHT AND
REVISED THE AVIATION DISCUSSION.
.SYNOPSIS...A WEAK STORM SYSTEM OFF THE COAST OF NORTHERN BAJA
WILL BRING A FEW RESIDUAL SHOWERS TO THE KERN COUNTY DESERT
TONIGHT. DRY WEATHER WILL PREVAIL ELSEWHERE AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE NORTH. THE RIDGE WILL BRING CLEAR
SKIES AND ABOVE NORMAL AFTERNOON TEMPERATURES TO THE DISTRICT
THURSDAY THROUGH FRIDAY.
&&
.DISCUSSION...UPPER LEVEL LOW CONTINUES TO SPIN ITS WHEELS OFF THE
COAST OF NORTHERN BAJA THIS EVENING. ALTHOUGH SHOWER ACTIVITY
DIMINISHED SHORTLY AFTER SUNSET IN THE MOUNTAINS...RADAR IS STILL
PICKING UP SOME LIGHT RAIN IN THE KERN COUNTY DESERT AS MOISTURE
WRAPS AROUND THE UPPER LEVEL LOW IN THE NORTHEAST FLOW ALOFT.
FARTHER NORTH AND WEST...MOISTURE IS HIGH BASED WITH A THIN VEIL
OF CIRRUS EXTENDING NORTHWARD TO FRESNO COUNTY.
A DRIER AIR MASS WILL SETTLE OVER THE CENTRAL CA INTERIOR TONIGHT
AND THURSDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS IN
FROM THE NORTH. THE RIDGE WILL DOMINATE OUR PATTERN THROUGH FRIDAY
BEFORE GETTING FLATTENED BY A WEAK SHORT WAVE TROUGH THAT TREKS
EASTWARD ACROSS THE NORTHERN PART OF THE STATE SATURDAY. THE
MODELS FORECAST A ZONAL FLOW ALOFT TO RESIDE OVER CENTRAL CA IN
THE 3 TO 7 DAY PERIOD. A SERIES OF WEAK UPPER LEVEL DISTURBANCES
WILL TRACK THROUGH THE PAC NW NEXT WEEK. ONE OF THESE SYSTEMS
COULD BRUSH YNP WITH SOME LIGHT PRECIP MONDAY INTO MONDAY NIGHT
BUT IT IS A VERY LOW CHANCE AT THIS POINT. OTHERWISE...DRY
WEATHER WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR FOR
THE NEXT 7 DAYS.
&&
.PREV DISCUSSION... /ISSUED 233 PM PDT WED MAR 18 2015/
DISCUSSION...PER LATEST HRRR GUIDANCE...ADDED IN SOME SLIGHT
CHANCE POPS IN SJ VALLEY IN TULARE COUNTY INCLUDING AS FAR WEST AS
VISALIA AND TULARE. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN
HIGHER ELEVATIONS OF SIERRA NEVADA MAINLY IN TULARE AND FRESNO
COUNTIES AROUND WET MEADOWS AND UPPER BURNT CORRAL. STEERING FLOWS
OF SIERRA THUNDERSTORMS ARE MAINLY FROM NORTHEAST AND COULD
GENERATE SHOWERS AND THUNDERSTORMS LOWER OVER FOOTHILLS OVER NEXT
FEW HOURS...OR THRU AROUND SUNSET.
&&
.AVIATION...
AREAS OF MVFR CONDITIONS OVER THE SIERRA NEVADA AND TEHACHAPI RANGE
THROUGH 16Z THURSDAY. A SHOWER MAY STILL BE POSSIBLE ACROSS THE KERN
COUNTY DESERT THROUGH 12Z THURSDAY. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CENTRAL CA INTERIOR FOR THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 03-18 87:2004 50:1991 57:1910 32:1898
KFAT 03-19 86:1928 50:1894 58:1916 32:1898
KFAT 03-20 89:1960 52:1897 59:1896 33:1982
KBFL 03-18 92:2004 51:1919 58:2004 23:1900
KBFL 03-19 90:1928 49:1919 60:1934 31:1903
KBFL 03-20 93:2004 52:1919 59:1909 32:1935
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...DURFEE
AVN/FW...MOLINA
PREV DISCUSSION...BSO
SYNOPSIS...DURFEE
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1034 PM PDT WED MAR 18 2015
.UPDATE...REMOVED SHOWERS FROM THE SIERRA ZONES FOR TONIGHT.
.SYNOPSIS...A WEAK STORM SYSTEM OFF THE COAST OF NORTHERN BAJA
WILL BRING A FEW RESIDUAL SHOWERS TO THE KERN COUNTY DESERT
TONIGHT. DRY WEATHER WILL PREVAIL ELSEWHERE AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE NORTH. THE RIDGE WILL BRING CLEAR
SKIES AND ABOVE NORMAL AFTERNOON TEMPERATURES TO THE DISTRICT
THURSDAY THROUGH FRIDAY.
&&
.DISCUSSION...UPPER LEVEL LOW CONTINUES TO SPIN ITS WHEELS OFF THE
COAST OF NORTHERN BAJA THIS EVENING. ALTHOUGH SHOWER ACTIVITY
DIMINISHED SHORTLY AFTER SUNSET IN THE MOUNTAINS...RADAR IS STILL
PICKING UP SOME LIGHT RAIN IN THE KERN COUNTY DESERT AS MOISTURE
WRAPS AROUND THE UPPER LEVEL LOW IN THE NORTHEAST FLOW ALOFT.
FARTHER NORTH AND WEST...MOISTURE IS HIGH BASED WITH A THIN VEIL
OF CIRRUS EXTENDING NORTHWARD TO FRESNO COUNTY.
A DRIER AIR MASS WILL SETTLE OVER THE CENTRAL CA INTERIOR TONIGHT
AND THURSDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS IN
FROM THE NORTH. THE RIDGE WILL DOMINANT OUR PATTERN THROUGH FRIDAY
BEFORE GETTING FLATTENED BY A WEAK SHORT WAVE TROUGH THAT TREKS
EASTWARD ACROSS THE NORTHERN PART OF THE STATE SATURDAY. THE
MODELS FORECAST A ZONAL FLOW ALOFT TO RESIDE OVER CENTRAL CA IN
THE 3 TO 7 DAY PERIOD. A SERIES OF WEAK UPPER LEVEL DISTURBANCES
WILL TRACK THROUGH THE PAC NW NEXT WEEK. ONE OF THESE SYSTEMS
COULD BRUSH YNP WITH SOME LIGHT PRECIP MONDAY INTO MONDAY NIGHT
BUT IT IS A LONG SHOT AT THIS POINT. OTHERWISE...DRY WEATHER WILL
PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 7 DAYS.
&&
.PREV DISCUSSION... /ISSUED 233 PM PDT WED MAR 18 2015/
DISCUSSION...PER LATEST HRRR GUIDANCE...ADDED IN SOME SLIGHT
CHANCE POPS IN SJ VALLEY IN TULARE COUNTY INCLUDING AS FAR WEST AS
VISALIA AND TULARE. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN
HIGHER ELEVATIONS OF SIERRA NEVADA MAINLY IN TULARE AND FRESNO
COUNTIES AROUND WET MEADOWS AND UPPER BURNT CORRAL. STEERING FLOWS
OF SIERRA THUNDERSTORMS ARE MAINLY FROM NORTHEAST AND COULD
GENERATE SHOWERS AND THUNDERSTORMS LOWER OVER FOOTHILLS OVER NEXT
FEW HOURS...OR THRU AROUND SUNSET.
&&
.AVIATION...
AREAS OF MVFR AND LOCAL IFR IN MOUNTAIN OBSCURATIONS 19Z WED THRU
06Z THU OVER THE SOUTHERN SIERRA NEVADA AND KERN COUNTY MOUNTAINS
WITH ISOLATED THUNDERSTORMS POSSIBLE. A FEW THUNDERSTORMS ALSO
POSSIBLE IN THE KERN COUNTY DESERT. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CENTRAL CA INTERIOR FOR THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 03-18 87:2004 50:1991 57:1910 32:1898
KFAT 03-19 86:1928 50:1894 58:1916 32:1898
KFAT 03-20 89:1960 52:1897 59:1896 33:1982
KBFL 03-18 92:2004 51:1919 58:2004 23:1900
KBFL 03-19 90:1928 49:1919 60:1934 31:1903
KBFL 03-20 93:2004 52:1919 59:1909 32:1935
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...DURFEE
AVN/FW...MOLINA
PREV DISCUSSION...BSO
SYNOPSIS...DURFEE
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1209 PM MDT THU MAR 19 2015
.UPDATE...
ISSUED AT 1206 PM MDT THU MAR 19 2015
BACK EDGE OF HEAVIER/STEADIER PRECIP DROPPING SLOWLY SOUTH THROUGH
THE AREA...AND HAVE BEGUN TO TAPER OFF POPS FROM NORTH TO SOUTH
ACCORDINGLY. HAVE KEPT CURRENT SET OF WINTER HIGHLIGHTS
INTACT...WILL LIKELY END CENTRAL MOUNTAINS/TELLER COUNTY EARLY
WITH NEXT FORECAST UPDATE LATER THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1102 AM MDT THU MAR 19 2015
BACK EDGE OF STEADIER/HEAVIER PRECIP ALREADY THROUGH KCOS AS OF
17Z...AND WILL LIKELY MOVE THROUGH KPUB AROUND 19Z. A FEW SHOWERS
WILL STILL LINGER BOTH SITES FOR THE REMAINDER OF THE
AFTERNOON...THOUGH CONDITIONS WILL BE PREDOMINATELY VFR WITH ONLY
SOME BRIEF MVFR UNDER HEAVIER SHOWERS. AT KALS...LOWER CLOUDS AND
A FEW SHOWERS WILL PERSIST INTO THE AFTERNOON...WITH PERIODS OF
MVFR UNTIL 01Z. ALL TERMINALS WILL BECOME VFR THIS EVENING AS
SKIES GRADUALLY CLEAR BEHIND DEPARTING WEATHER SYSTEM...WITH VFR
CONDITIONS OVERNIGHT INTO FRIDAY MORNING.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL REMAIN OBSCURRED BY
-SHRA/-SHSN THROUGH THE AFTERNOON...BEFORE IMPROVING CONDITIONS
WORK FROM NORTH TO SOUTH ACROSS THE AREA EARLY THIS EVENING. BY
06Z...VFR MOST LOCATIONS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ066-068-072-
074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
&&
$$
UPDATE...PETERSEN
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1109 AM MDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1102 AM MDT THU MAR 19 2015
BACK EDGE OF STEADIER/HEAVIER PRECIP ALREADY THROUGH KCOS AS OF
17Z...AND WILL LIKELY MOVE THROUGH KPUB AROUND 19Z. A FEW SHOWERS
WILL STILL LINGER BOTH SITES FOR THE REMAINDER OF THE
AFTERNOON...THOUGH CONDITIONS WILL BE PREDOMINATELY VFR WITH ONLY
SOME BRIEF MVFR UNDER HEAVIER SHOWERS. AT KALS...LOWER CLOUDS AND
A FEW SHOWERS WILL PERSIST INTO THE AFTERNOON...WITH PERIODS OF
MVFR UNTIL 01Z. ALL TERMINALS WILL BECOME VFR THIS EVENING AS
SKIES GRADUALLY CLEAR BEHIND DEPARTING WEATHER SYSTEM...WITH VFR
CONDITIONS OVERNIGHT INTO FRIDAY MORNING.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL REMAIN OBSCURRED BY
-SHRA/-SHSN THROUGH THE AFTERNOON...BEFORE IMPROVING CONDITIONS
WORK FROM NORTH TO SOUTH ACROSS THE AREA EARLY THIS EVENING. BY
06Z...VFR MOST LOCATIONS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ072-074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ066-068.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
429 AM MDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 428 AM MDT THU MAR 19 2015
IFR CONDITIONS CAN BE EXPECTED IN AND NEAR THE MOUNTAINS TODAY WITH
WIDESPREAD SNOW SHOWERS. HOWEVER...THE TAF SITES ARE EXPECTED TO
REMAIN PREDOMINANTLY MVFR WITH RAIN SHOWERS THROUGH THE DAY. KCOS
COULD SEE A BRIEF MIX WITH SNOW WHICH MAY BRIEFLY CAUSE CIGS AND VIS
TO APPROACH IFR THIS MORNING. KALS WILL LIKELY SEE PRECIP IN THE
FORM OF RAIN...WHICH WILL SPREAD BACK IN LATE THIS MORNING THROUGH
THIS AFTERNOON WITH VFR TO BRIEF MVFR CONDITIONS POSSIBLE. SHOWERS
WILL DIMINISH FROM NORTHEAST TO SOUTHWEST THROUGH THE LATE AFTERNOON
AND EVENING HOURS WITH VFR CONDITIONS EXPECTED BY LATE EVENING FOR
KCOS AND KPUB. DEPENDING ON THE AMOUNT OF CLEARING WHICH TAKES
PLACE OVERNIGHT...KALS COULD SEE SOME PATCHY FOG DEVELOP EARLY
FRIDAY MORNING...BUT PROBABILITY LOOKS LOW AT THIS POINT DUE TO
LIKELIHOOD OF SOME PERSISTENT MID/HIGH CLOUDINESS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ072-074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 AM MDT FRIDAY FOR
COZ066-068.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...KT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1142 PM EDT FRI MAR 20 2015
.SYNOPSIS...
LOW PRESSURE WILL PASS TO THE SOUTH OVERNIGHT. WEAK HIGH PRESSURE
WILL BUILD IN ON SATURDAY. A COLD FRONT WILL PASS THROUGH SATURDAY
EVENING...FOLLOWED BY CANADIAN HIGH PRESSURE THROUGH WEDNESDAY.
LOW PRESSURE WILL APPROACH FROM THE WEST LATE WEDNESDAY AND
WEDNESDAY NIGHT...WITH ITS ASSOCIATED COLD FRONT SLOWLY MOVING
ACROSS THURSDAY AND THURSDAY NIGHT. HIGH PRESSURE WILL RETURN ON
FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
FOR THE MOST PART...ACCUMULATING SNOW HAS COME TO AND END.
LIGHT SNOW IS TRANSITIONING TO A LIGHT WINTRY MIX...AS WARM LAYER
WITH ABOVE-FREEZING TEMPS ALOFT PUSHES IN FROM THE SOUTH AND
CHANCES OF ICE NUCLEATION FROM THE MID LEVELS DECREASES.
THE CHALLENGING FACTOR IS THAT MODELS INDICATING LOW-LEVELS WILL
BE SATURATED THROUGH ABOUT 700 MB ON AN ONSHORE FLOW PRESENTING
SEA SALT NUCLEI...WHICH LOWERS NUCLEATION CRITERIA AND WOULD KEEP
SNOW IN THE MIX. SO OVERALL...EXPECTATION IS A MIXTURE OF
-SN/-FZDZ AND -DZ IN WARMER SPOTS...WITH A TRACE TO A COUPLE
HUNDREDTHS OF AN INCH OF ICE ACCRETION POSSIBLE.
TEMPERATURES SHOULD REMAIN NEARLY STEADY OVERNIGHT...MID 20S TO
LOWER 30S.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
LOOKS LIKE MID LEVELS MOISTEN UP BY AROUND DAYBREAK ON SATURDAY...
SO WITH LINGERING LOW CHANCES OF PCPN STILL AROUND FOR THE FIRST
HALF OF THE MORNING...WILL GO WITH PCPN TYPE OF SNOW. DRY WEATHER
OTHERWISE FOR THE AFTERNOON WITH PARTIAL CLEARING. SIDED WITH THE
COLDER GUIDANCE FOR HIGH TEMPERATURES DUE TO EXPECTED CLOUD COVER
AND SOME SNOW ON THE GROUND. A COLD FRONT PASSES THROUGH LATE
AFTERNOON INTO EARLY EVENING WITH AN ISOLATED SPRINKLE. A MAV/NAM
MOS BLEND WAS USED FOR LOW TEMPS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
A CLOSED 850-500 HPA LOW PASSES TO THE N SUNDAY AND SUNDAY
NIGHT...WITH ITS ASSOCIATED TROUGH AXIS STAYING TO THE N AS WELL.
SO WITH NO SHORTWAVES FORECAST TO MOVE THROUGH AROUND THE BASE OF
THE TROUGH...SHOULD REMAIN DRY.
700 HPA TROUGH AXIS BUILDS IN MONDAY...FOLLOWED BY 500 HPA TROUGH
AXIS BUILDING IN MONDAY NIGHT...THEN SLIDING TO THE EAST ON TUESDAY.
DOWNSLOPING BOUNDARY LAYER FLOW COUPLED WITH RELATIVELY DRY LOW
LEVELS PROMPT A DRY FORECAST IN THIS TIME FRAME.
DEEP LAYERED RIDGING BUILDS IN TUESDAY NIGHT...THEN SLIDES TO THE
EAST ON MONDAY. SUBSIDENCE UNDER THE RIDGE SHOULD KEEP THINGS DRY
TUESDAY NIGHT AND WEDNESDAY MORNING. WSW-SW LOW LEVEL RETURN FLOW
WEDNESDAY AFTERNOON WILL BRING AN INCREASE IN LOW LEVEL
MOISTURE...AND WITH 700 HPA SHORTWAVE PROGGED TO BE WORKING UP THE
BACKSIDE OF THE DEPARTING RIDGE...COULD BRING A CHANCE OF SHOWERS TO
W ZONES WEDNESDAY AFTERNOON.
MODELS HAVE TRENDED SLOWER WITH THE SYSTEM FOR LATE NEXT...WITH
INDICATIONS OF ONLY SPOTTY SHOWERS WEDNESDAY NIGHT...THEN MORE
WIDESPREAD SHOWERS ON THURSDAY. GIVEN INHERENT UNCERTAINTY IN THIS
TIME FRAME HAVE CAPPED POPS ON THURSDAY AT CHANCE FOR NOW.
DIFFERENCES THEN ARISE BETWEEN THE ECMWF AND GFS WITH REGARDS TO THE
EXTENT ENERGY EJECTS FROM A TROUGH FROM THE SW US BACK INTO BAJA
CALIFORNIA LATE IN THE WEEK. THE GFS EJECTS MORE
ENERGY...INTERACTING WITH THE NORTHERN STREAM AND RESULTING IN A
SLOWER FRONTAL PASSAGE WITH WAVES OF LOW PRESSURE RIDING ALONG THE
FRONT - AND HENCE A RELATIVELY WET FORECAST. THE ECMWF DOES NOT
EJECT AS MUCH ENERGY/NOR HAVE MUCH IF ANY PHASING...SO IT HAS A
QUICKER FRONTAL PASSAGE...AND HENCE A DRY FORECAST. CMC SEEMS AT 144
HOURS (LAST TIME AVAILABLE) TO BE MORE TOWARDS THE GFS THAN THE
ECMWF BUT NOT QUITE AS AMPLIFIED. NOTING THAT...DO HAVE SLIGHT
CHANCE POPS CHANCE POPS IN FOR THURSDAY NIGHT THEN SLIGHT CHANCE
POPS IN FOR FRIDAY. VERY LOW CONFIDENCE FORECAST IN THIS TIME FRAME.
FOR TEMPERATURES SUNDAY-FRIDAY...
FOR HIGHS SUNDAY USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 850-825 HPA. HIGHS SHOULD BE
AROUND 10-15 DEGREES BELOW NORMAL. A BLEND OF MAV/MET GUIDANCE AND
NAM 2-METER TEMPERATURES WAS USED FOR LOWS SUNDAY NIGHT...WITH
VALUES FORECAST TO BE AROUND 10 DEGREES BELOW NORMAL. HIGHS MONDAY
WERE BASED ON A BLEND OF MEX/WPC GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 875 HPA. HIGHS SHOULD BE AROUND
10-15 DEGREES BELOW NORMAL.
TEMPERATURES MONDAY NIGHT-FRIDAY WERE BASED ON A BLEND OF MEX/WPC
GUIDANCE WITH TEMPERATURES MODERATING THROUGH THE PERIOD TO SLIGHTLY
BELOW NORMAL ON WEDNESDAY...THEN TO ABOVE NORMAL ON THURSDAY. FOR
NOW FORECASTING A RETURN TO BELOW NORMAL TEMPERATURES ON FRIDAY -
BUT STILL QUITE A BIT OF UNCERTAINTY ON WHAT ACTUAL PATTERN WILL BE
THEN.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
LOW PRESSURE TRACKS SOUTH OF THE REGION TONIGHT. A COLD FRONT
PASSES THROUGH THE REGION ON SATURDAY.
ACCUMULATING SNOW HAS ENDED WITH CONDS COMING UP TO MVFR IN MANY
SPOTS. MODEL SOUNDINGS AND GUIDANCE PROJECTING THAT THIS SHOULD BE
SHORT LIVED...AS SATURATED LOW-LEVELS SHOULD RE- DEVELOP IFR TO
LOCALLY LIFR CONDITIONS OVERNIGHT IN AREAS OF -FZDZSN. CONFIDENCE
ON THIS IS LOW TO MODERATE THOUGH...AS NARRE AND HRRR ARE NOT AS
ROBUST/WIDESPREAD WITH IFR CONDS...PARTICULARLY THE
INTERIOR...AND UPSTREAMS OBS ARE GENERALLY MVFR.
CONDITIONS EXPECTED TO GRADUALLY IMPROVE TO MVFR SATURDAY
MORNING INTO AFTERNOON. HIGH CONFIDENCE IN VFR CONDS IN WAKE OF
COLD FRONTAL PASSAGE LATE IN THE DAY.
LIGHT NE FLOW CONTINUES TO BACK N AND THEN NW OVERNIGHT INTO SAT
MORNING. WINDS LIKELY BACK SW SAT AFTERNOON AHEAD OF COLD FRONTAL
PASSAGE...BEFORE SHIFTING WNW IN THE EVENING IN ITS WAKE.
OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...
.SAT NIGHT...VFR.
.SUN...VFR. NW GUSTS AROUND 25 KT AM...AROUND 20 KT PM.
.MON...VFR. NW GUSTS AROUND 20 KT.
.TUE...VFR.
.WED...CHANCE OF SUB-VFR LATE WEDNESDAY.
&&
.MARINE...
WINDS HAVE PICKED UP AS LOW PRESSURE PASSES TO THE SOUTH... WITH
GUSTS 25-30 KT ON THE OCEAN WATERS...AND SEAS BUILDING TO 5-7 FT.
WILL LEAVE THE SCA UP THROUGH SATURDAY AFTERNOON...BUT THIS MIGHT
NEED TO BE EXTENDED IN TIME FOR LINGERING 5 FT SEAS SATURDAY NIGHT.
SCA CONDITIONS ARE LIKELY ON THE COASTAL OCEAN WATERS AND
EASTERN SOUND ON SUNDAY...AND POSSIBLE ELSEWHERE - THOUGH FOR NOW
GOING FOR GUSTS TO 20 KT ON THESE WATERS. THE GRADIENT THEN RELAXES
OVER THE WATERS...WITH SUB-SCA CONDITIONS FORECAST FROM SUNDAY NIGHT-
WEDNESDAY.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS FORECAST FROM SUNDAY INTO
WEDNESDAY.
ICE BREAKUP/MOVEMENT ACROSS THE LOWER HUDSON VALLEY AND
CONNECTICUT RIVERS/STREAMS IS EXPECTED TO BE LIMITED THROUGH EARLY
NEXT WEEK WITH LITTLE RUNOFF AND BELOW SEASONABLE TEMPS. ISOLATED
ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD RESULT IN
LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS UNPREDICTABLE AND
SUDDEN...INTERESTS ALONG ICE COVERED RIVERS SHOULD MONITOR NWS
FORECASTS FOR THE LATEST INFORMATION.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.AFTER THAT...NO SIGNIFICANT PCPN IS EXPECTED
THROUGH THE MIDDLE OF NEXT WEEK.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDE LEVELS ARE RUNNING RATHER HIGH DUE TO NEW
MOON. HIGH TIDE ALONG NYC HARBOR AND GREAT SOUTH BAY HAVE
PASSED WITH WATER LEVELS STAYING BELOW MINOR. THE MOST VULNERABLE
SPOTS ALONG WESTERN LI SOUND MAY BRIEFLY TOUCHING MINOR FLOODING
THRESHOLDS WITH A SURGE OF ONLY 1/2 FT NEEDED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR CTZ005>012.
NY...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR NYZ067>075-
078>081-176>179.
NJ...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR NJZ002-004-
006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...GOODMAN/MALOIT
NEAR TERM...GOODMAN
SHORT TERM...JC
LONG TERM...MALOIT
AVIATION...NV
MARINE...GOODMAN/MALOIT
HYDROLOGY...GOODMAN/MALOIT
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1120 PM EDT FRI MAR 20 2015
.SYNOPSIS...
LOW PRESSURE PASSES TO THE SOUTH OVERNIGHT...WITH WEAK HIGH
PRESSURE BUILDING IN FOR SATURDAY. A COLD FRONT THEN PASSES
THROUGH SATURDAY EVENING. CANADIAN HIGH PRESSURE BUILDS IN THROUGH
TUESDAY NIGHT...THEN BEGINS TO SLIDE OFFSHORE ON WEDNESDAY. A LOW
PRESSURE SYSTEM APPROACHES FROM THE WEST LATE WEDNESDAY AND
WEDNESDAY NIGHT...WITH ITS ASSOCIATED COLD FRONT SLOWLY CROSSING
THE AREA THURSDAY AND THURSDAY NIGHT. HIGH PRESSURE THEN BUILDS IN
FOR FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
FOR THE MOST PART...ACCUMULATING SNOW HAS COME TO AND END. LIGHT
SNOW SHOULD TRANSITION TO LIGHT WINTRY MIX
OVERNIGHT...PARTICULARLY NYC/NJ METRO AND LI...AS WARM LAYER WITH
ABOVE-FREEZING TEMPS ALOFT PUSHES IN FROM THE SOUTH AND CHANCES
OF ICE NUCLEATION FROM THE MID LEVELS DECREASES. THE CHALLENGING
FACTOR IS THAT MODELS INDICATING LOW-LEVELS WILL BE SATURATED
THROUGH ABOUT 700 MB ON AN ONSHORE FLOW PRESENTING SALT
NUCLEI...WHICH LOWERS NUCLEATION CRITERIA AND WOULD KEEP SNOW IN
THE MIX. SO OVERALL...EXPECTATION IS A MIXTURE OF -SN/-FZDZ AND
-DZ IN WARMER SPOTS...WITH A TRACE TO A COUPLE HUNDREDTHS OF AN
INCH OF ICE ACCRETION POSSIBLE.
TEMPERATURES SHOULD REMAIN NEARLY STEADY TONIGHT...UPPER 20S TO
LOWER 30S.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
LOOKS LIKE MID LEVELS MOISTEN UP BY AROUND DAYBREAK ON SATURDAY...
SO WITH LINGERING LOW CHANCES OF PCPN STILL AROUND FOR THE FIRST
HALF OF THE MORNING...WILL GO WITH PCPN TYPE OF SNOW. DRY WEATHER
OTHERWISE FOR THE AFTERNOON WITH PARTIAL CLEARING. SIDED WITH THE
COLDER GUIDANCE FOR HIGH TEMPERATURES DUE TO EXPECTED CLOUD COVER
AND SOME SNOW ON THE GROUND. A COLD FRONT PASSES THROUGH LATE
AFTERNOON INTO EARLY EVENING WITH AN ISOLATED SPRINKLE. A MAV/NAM
MOS BLEND WAS USED FOR LOW TEMPS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
CLOSED 850-500 HPA LOW PASSES
TO THE N OF THE AREA SUNDAY AND SUNDAY NIGHT...WITH ITS ASSOCIATED
TROUGH AXIS STAYING TO THE N AS WELL. SO WITH NO SHORTWAVES FORECAST
TO MOVE THROUGH AROUND THE BASE OF THE TROUGH...SHOULD REMAIN DRY.
700 HPA TROUGH AXIS BUILDS IN MONDAY...FOLLOWED BY 500 HPA TROUGH
AXIS BUILDING IN MONDAY NIGHT...THEN SLIDING TO THE EAST ON TUESDAY.
DOWNSLOPING BOUNDARY LAYER FLOW COUPLED WITH RELATIVELY DRY LOW
LEVELS PROMPT A DRY FORECAST IN THIS TIME FRAME.
DEEP LAYERED RIDGING BUILDS IN TUESDAY NIGHT...THEN SLIDES TO THE
EAST ON MONDAY. SUBSIDENCE UNDER THE RIDGE SHOULD KEEP THINGS DRY
TUESDAY NIGHT AND WEDNESDAY MORNING. WSW-SW LOW LEVEL RETURN FLOW
WEDNESDAY AFTERNOON WILL BRING AN INCREASE IN LOW LEVEL
MOISTURE...AND WITH 700 HPA SHORTWAVE PROGGED TO BE WORKING UP THE
BACKSIDE OF THE DEPARTING RIDGE...COULD BRING A CHANCE OF SHOWERS TO
W ZONES WEDNESDAY AFTERNOON.
MODELS HAVE TRENDED SLOWER WITH THE SYSTEM FOR LATE NEXT...WITH
INDICATIONS OF ONLY SPOTTY SHOWERS WEDNESDAY NIGHT...THEN MORE
WIDESPREAD SHOWERS ON THURSDAY. GIVEN INHERENT UNCERTAINTY IN THIS
TIME FRAME HAVE CAPPED POPS ON THURSDAY AT CHANCE FOR NOW.
DIFFERENCES THEN ARISE BETWEEN THE ECMWF AND GFS WITH REGARDS TO THE
EXTENT ENERGY EJECTS FROM A TROUGH FROM THE SW US BACK INTO BAJA
CALIFORNIA LATE IN THE WEEK. THE GFS EJECTS MORE
ENERGY...INTERACTING WITH THE NORTHERN STREAM AND RESULTING IN A
SLOWER FRONTAL PASSAGE WITH WAVES OF LOW PRESSURE RIDING ALONG THE
FRONT - AND HENCE A RELATIVELY WET FORECAST. THE ECMWF DOES NOT
EJECT AS MUCH ENERGY/NOR HAVE MUCH IF ANY PHASING...SO IT HAS A
QUICKER FRONTAL PASSAGE...AND HENCE A DRY FORECAST. CMC SEEMS AT 144
HOURS (LAST TIME AVAILABLE) TO BE MORE TOWARDS THE GFS THAN THE
ECMWF BUT NOT QUITE AS AMPLIFIED. NOTING THAT...DO HAVE SLIGHT
CHANCE POPS CHANCE POPS IN FOR THURSDAY NIGHT THEN SLIGHT CHANCE
POPS IN FOR FRIDAY. VERY LOW CONFIDENCE FORECAST IN THIS TIME FRAME.
FOR TEMPERATURES SUNDAY-FRIDAY...
FOR HIGHS SUNDAY USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 850-825 HPA PER BUFKIT SOUNDINGS.
HIGHS SHOULD BE AROUND 10-15 DEGREES BELOW NORMAL. A BLEND OF
MAV/MET GUIDANCE AND NAM 2-METER TEMPERATURES WAS USED FOR LOWS
SUNDAY NIGHT...WITH VALUES FORECAST TO BE AROUND 10 DEGREES BELOW
NORMAL. HIGHS MONDAY WERE BASED ON A BLEND OF MEX/WPC GUIDANCE WITH
NAM 2-METER TEMPERATURES AND A MIX DOWN FROM 875 HPA PER BUFKIT
SOUNDINGS. HIGHS SHOULD BE AROUND 10-15 DEGREES BELOW NORMAL.
TEMPERATURES MONDAY NIGHT-FRIDAY WERE BASED ON A BLEND OF MEX/WPC
GUIDANCE WITH TEMPERATURES MODERATING THROUGH THE PERIOD TO SLIGHTLY
BELOW NORMAL ON WEDNESDAY...THEN TO ABOVE NORMAL ON THURSDAY. FOR
NOW FORECASTING A RETURN TO BELOW NORMAL TEMPERATURES ON FRIDAY -
BUT STILL QUITE A BIT OF UNCERTAINTY ON WHAT ACTUAL PATTERN WILL BE
THEN.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
LOW PRESSURE TRACKS SOUTH OF THE REGION TONIGHT. A COLD FRONT
PASSES THROUGH THE REGION ON SATURDAY.
ACCUMULATING SNOW HAS ENDED WITH CONDS COMING UP TO MVFR IN MANY
SPOTS. MODEL SOUNDINGS AND GUIDANCE PROJECTING THAT THIS SHOULD BE
SHORT LIVED...AS SATURATED LOW-LEVELS SHOULD RE- DEVELOP IFR TO
LOCALLY LIFR CONDITIONS OVERNIGHT IN AREAS OF -FZDZSN. CONFIDENCE
ON THIS IS LOW TO MODERATE THOUGH...AS NARRE AND HRRR ARE NOT AS
ROBUST/WIDESPREAD WITH IFR CONDS...PARTICUALRLY THE INTERIOR...AND
UPSTREAMS OBS ARE GENERALLY MVFR.
CONDITIONS EXPECTED TO GRADUALLY IMPROVE TO MVFR SATURDAY
MORNING INTO AFTERNOON. HIGH CONFIDENCE IN VFR CONDS IN WAKE OF
COLD FRONTAL PASSAGE LATE IN THE DAY.
LIGHT NE FLOW CONTINUES TO BACK N AND THEN NW OVERNIGHT INTO SAT
MORNING. WINDS LIKELY BACK SW SAT AFTERNOON AHEAD OF COLD FRONTAL
PASSAGE...BEFORE SHIFTING WNW IN THE EVENING IN ITS WAKE.
OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...
.SAT NIGHT...VFR.
.SUN...VFR. NW GUSTS AROUND 25 KT AM...AROUND 20 KT PM.
.MON...VFR. NW GUSTS AROUND 20 KT.
.TUE...VFR.
.WED...CHANCE OF SUB-VFR LATE WEDNESDAY.
&&
.MARINE...
WINDS WILL PICK UP TONIGHT AS LOW PRESSURE PASSES TO THE
SOUTH...INCREASING THE PRESSURE GRADIENT. THIS BRING 25 KT GUSTS TO
THE OCEAN WATERS WHILE BUILDING SEAS TO 5 FT OR MORE. WILL LEAVE THE
SCA UP THROUGH SATURDAY AFTERNOON...BUT THIS MIGHT NEED TO BE
EXTENDED IN TIME FOR LINGERING 5 FT SEAS SATURDAY NIGHT.
SCA CONDITIONS ARE LIKELY ON THE COASTAL OCEAN WATERS AND
EASTERN SOUND ON SUNDAY...AND POSSIBLE ELSEWHERE - THOUGH FOR NOW
GOING FOR GUSTS TO 20 KT ON THESE WATERS. THE GRADIENT THEN RELAXES
OVER THE WATERS...WITH SUB-SCA CONDITIONS FORECAST FROM SUNDAY NIGHT-
WEDNESDAY.
&&
.HYDROLOGY...
LIGHT WINTRY MIX EXPECTED OVERNIGHT...WITH A FEW HUNDREDTHS OF AN
INCH QPF.
THEREAFTER...NO SIGNIFICANT PRECIPITATION IS FORECAST FROM SUNDAY
INTO WEDNESDAY.
ICE BREAKUP/MOVEMENT ACROSS THE LOWER HUDSON VALLEY AND
CONNECTICUT RIVERS/STREAMS IS EXPECTED TO BE LIMITED THROUGH EARLY
NEXT WEEK WITH LITTLE RUNOFF AND BELOW SEASONABLE TEMPS. ISOLATED
ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD RESULT IN
LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS UNPREDICTABLE AND
SUDDEN...INTERESTS ALONG ICE COVERED RIVERS SHOULD MONITOR NWS
FORECASTS FOR THE LATEST INFORMATION.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.AFTER THAT...NO SIGNIFICANT PCPN IS EXPECTED
THROUGH THE MIDDLE OF NEXT WEEK.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDE LEVELS ARE RUNNING RATHER HIGH DUE TO NEW
MOON. HIGH TIDE ALONG NYC HARBOR AND GREAT SOUTH BAY HAVE
PASSED WITH WATER LEVELS STAYING BELOW MINOR. THE MOST VULNERABLE
SPOTS ALONG WESTERN LI SOUND MAY BRIEFLY TOUCHING MINOR FLOODING
THRESHOLDS WITH A SURGE OF AROUND 1/2 FT NEEDED TO REACH THIS
THRESHOLDS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR CTZ005>012.
NY...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR NYZ067>075-
078>081-176>179.
NJ...WINTER WEATHER ADVISORY UNTIL 4 AM EDT SATURDAY FOR NJZ002-004-
006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...JC/MALOIT
NEAR TERM...JC/NV
SHORT TERM...JC
LONG TERM...MALOIT
AVIATION...NV
MARINE...JC/MALOIT
HYDROLOGY...JC/MALOIT/NV
TIDES/COASTAL FLOODING...NV
AREA FORECAST DISCUSSION
NWS ALBANY NY
710 PM EDT FRI MAR 20 2015
.SYNOPSIS...
A STORM SYSTEM PASSING TO THE SOUTH WILL BRING SOME
LIGHT SNOW TO THE REGION THROUGH THIS EVENING...MAINLY FOR AREAS TO
THE SOUTH OF ALBANY. AN ARCTIC COLD FRONT WILL BRING SOME ADDITIONAL
RAIN AND SNOW SHOWERS TO THE REGION ON SATURDAY...BEFORE YET ANOTHER
VERY COLD AIR MASS MOVES INTO THE REGION FOR SUNDAY INTO EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 615 PM EDT...THE COMBINATION OF SFC LOW PRESSURE OFF THE
DELMARVA COAST...AND A FAST MOVING SHORTWAVE MOVING ACROSS THE
MID ATLANTIC REGION HAVE ALLOWED FOR A PERIOD OF LIGHT SNOWFALL
OVER THE REGION LATE THIS AFTERNOON. THE STEADIEST SNOWFALL HAS
BEEN FROM THE CAPITAL REGION ON SOUTHWARD...WITH THE HIGHEST
REFLECTIVITY ECHOS ON KENX RADAR OVER THE SOUTHERN BERKSHIRES AND
NW CT.
WITH THIS BEING A FAST MOVING SYSTEM...PRECIP LOOKS TO BE COMING
TO AN END THIS EVENING. THE REGIONAL MOSAIC RADAR ALREADY SHOWS
THE BACK EDGE OF THE STEADY PRECIP SHIELD ACROSS CENTRAL NY AND
IT/S ADVANCING EASTWARD. THE LATEST 21Z 3KM HRRR SHOWS THE STEADY
PRECIP SHOULD BE ENDING THIS EVENING BETWEEN 7 PM AND 9 PM...WITH
ONLY A FEW LINGERING SNOW SHOWERS FOR THE MID HUDSON VALLEY...NW
CT AND BERKSHIRES BETWEEN 9 PM AND 10 PM. TOTAL SNOWFALL WILL
RANGE FROM A COATING TO AN INCH FOR NORTHERN AND CENTRAL
AREAS...INCLUDING THE CAPITAL REGION...TO AROUND 1 TO 3 INCHES FOR
THE CATSKILLS...MID HUDSON VALLEY...TACONICS...BERKSHIRES AND NW
CT. ONLY FAR SOUTHERN AREAS WILL BE CLOSE TO THE HIGHER END OF THE
RANGE...AS SNOW RATIOS HAVE BEEN FAIRLY LOW AND THE LIGHT
INTENSITY HAS ALLOWED SOME MELTING DUE TO THE WARM GROUND AND
STRONG MARCH SUN.
AFTERWARD...IT SHOULD JUST REMAIN CLOUDY THROUGH THE REMAINDER OF
THE OVERNIGHT HOURS. WITH THE CLOUDS AROUND...TEMPS WON/T DROP TOO
MUCH...BUT OVERNIGHT LOWS LOOK TO BE IN THE 20S IN MOST AREAS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
ON SATURDAY...A STRONG ARCTIC FRONTAL BOUNDARY WILL BE APPROACHING
FROM THE GREAT LAKES REGION. THIS FRONT LOOKS TO CROSS DURING THE
AFTN HOURS FROM WEST TO EAST. THIS FRONT WILL HAVE A STRONG
THERMAL GRADIENT ASSOCIATED WITH IT...WITH TEMPS ALOFT RAPIDLY
DROPPING OFF BEHIND THE BOUNDARY.
AHEAD OF THE FRONT...SOUTHERLY FLOW SHOULD ALLOW TEMPS TO WARM
INTO THE UPPER 30S TO MID 40S ACROSS THE REGION. A BAND OF
PRECIPITATION LOOKS TO ACCOMPANY THE BOUNDARY. INITIALLY...PRECIP
WILL LIKELY BE RAIN SHOWERS. ALTHOUGH MOISTURE WILL BE
LIMITED...THE STRONG SFC CONVERGENCE SHOULD ALLOW FOR A BAND OF
SHOWERS FOR MOST AREAS. WITH MID LEVEL LAPSE RATES /700-500 HPA/
WILL BE AROUND 6-7 DEGREES C/KM...THE SHOWERS MAY HAVE SOME
CONVECTIVE GROWTH TO THEM...AND MAY BE CAPABLE OF PRODUCING SOME
GRAUPEL. THE 4KM BTV WRF SHOWS A BROKEN LINE OF THESE CONVECTIVE
SHOWERS WITH SOME HEAVIER ECHOES MOVING ACROSS THE AREA DURING THE
AFTN HOURS.
WITH THE RAPIDLY COOLING BOUNDARY LAYER...RAIN SHOWERS LOOKS TO
SWITCH OVER TO SNOW SHOWERS BEFORE ENDING...FIRST HAPPENING IN THE
HIGH TERRAIN. IT/S TOUGH TO SAY IF SHOWERS WILL LAST LONG ENOUGH
IN VALLEY AREAS FOR THESE TO BE A CHANGEOVER TO SNOW SHOWERS IN
THOSE AREAS BEFORE ENDING DURING THE EARLY EVENING. A QUICK
COATING TO AN INCH OR TWO IS POSSIBLE FOR THE HIGH TERRAIN...ESP
THE WESTERN AND SOUTHERN ADIRONDACKS. TEMPS SHOULD QUICKLY FALL
DURING THE EVENING HOURS.
OVERNIGHT LOWS ON SAT NIGHT LOOK TO BE IN THE TEENS FOR MOST
AREAS...WITH SOME SINGLE DIGITS IN THE ADIRONDACKS. MOST AREAS
WILL SEE PRECIP END WITH THE PASSAGE OF THE BOUNDARY ON SAT
EVENING...BUT SOME UPSLOPE AREAS MAY CONTINUE TO SEE SNOW SHOWERS
SAT NIGHT IN THE ADIRONDACKS AND GREENS. IN ADDITION...SOME LAKE
EFFECT ACTIVITY OFF LAKE ONTARIO MAY BRING SOME CELLULAR SNOW
SHOWERS ACROSS THE MOHAWK VALLEY AND SCHOHARIE COUNTY BY SAT
NIGHT INTO SUN MORNING AS WELL....BUT ADDITIONAL SNOW ACCUMULATION
LOOKS LIGHT.
ASIDE FROM A FEW UPSLOPE SNOW SHOWERS IN THE ADIRONDACKS AND
PERHAPS THE SOUTHERN GREENS ON SUNDAY...IT LOOKS DRY FOR SUN INTO
SUNDAY NIGHT. HOWEVER...IT WILL BE VERY COLD...AS 850 HPA TEMPS
FALL TO AROUND -20 DEGREES C. THESE COLD TEMPS ALOFT WILL PROMOTE
GOOD MIXING...SO IT WILL BE RATHER BREEZY DURING THE DAY SUNDAY AS
WELL...WITH GUSTS OVER 25 MPH POSSIBLE. MAX TEMPS WILL LIKELY ONLY
BE IN THE MID 20S TO MID 30S FOR VALLEY AREAS...WITH HIGH TERRAIN
HIGHS IN THE TEENS TO LOW 20S. THESE TEMPS ARE 15-20 DEGREES BELOW
NORMAL FOR THIS TIME OF YEAR.
TEMPS WILL CONTINUE TO BE VERY COLD FOR SUNDAY NIGHT...WITH LOWS
IN THE SINGLE DIGITS AND TEENS. A FEW SPOTS IN THE ADIRONDACKS
WILL EVEN FALL BELOW ZERO AS WELL. THE WINDS WILL DIMINISH
SOMEWHAT FOR SUNDAY NIGHT...BUT WON/T BECOME CALM. THIS WILL ALLOW
FOR WIND CHILL VALUES 10 BELOW TO 10 ABOVE FOR MOST
AREAS...ALTHOUGH WIND CHILL VALUES WILL BE 10 TO 20 BELOW FOR THE
ADIRONDACKS. WHILE THESE FALL SHORT OF WIND CHILL ADVISORY
CRITERIA...IT/S STILL VERY COLD FOR LATE MARCH.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THIS WILL BE A PERIOD OF MODERATING TEMPERATURES...WITH HIGH
TEMPERATURES BEGINNING MONDAY NIGHT FROM AROUND 20 DEGREES TO THE
UPPER 30S...AND BECOMING AROUND 15 TO 25 DEGREES MILDER BY
THURSDAY. LOW TEMPERATURES IN THE SINGLE DIGITS AND TEENS MONDAY
NIGHT WILL BE LONG GONE BY WEDNESDAY NIGHT AS READINGS WILL BE 15
TO 25 DEGREES MILDER.
THE PERIOD WILL BEGIN WITH HIGH PRESSURE AND DRY CONDITIONS...WITH A
STORM SYSTEM FROM THE ROCKIES BRINGING A MIX OF PRECIPITATION BY
WEDNESDAY NIGHT. THE MAIN LOW WILL SCOOT ACROSS THE GREAT LAKES AND
PASS JUST TO OUR NORTH THROUGH WEDNESDAY NIGHT...WITH THE
PRECIPITATION BECOMING MORE SHOWERY BUT STILL MIXED. COLD AIR
BEHIND THE COLD FRONT WILL LAG...BUT EVENTUALLY THE PRECIPITATION
WILL CHANGE OVER TO SNOW SHOWERS WHERE IT STILL LINGERS NORTH AND
WEST OF THE CAPITAL REGION THURSDAY NIGHT. BROAD HIGH PRESSURE
BUILDS OVER THE WESTERN HALF OF THE COUNTRY AND IS POISED TO MAKE IT
IN FOR THE NEXT WEEKEND.
&&
.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
FLIGHT CONDITIONS WILL BEGIN TO IMPROVE THIS EVENING ACROSS THE
TAF SITES AS THE STORM OFF THE DELMARVA PENINSULA MOVES OUT TO
SEA. BY 03Z EXPECT THE SNOW TO HAVE ENDED. HOWEVER...LOW LEVEL
MOISTURE AND LIGHT WINDS WILL RESULT IN CIGS REMAINING MVFR
THROUGH THE NIGHT...ALONG WITH SOME MVFR VISIBILITIES DUE TO FOG.
VISIBILITIES WILL IMPROVE THE VFR BY AROUND 14Z...BUT CEILINGS
SHOULD REMAIN MVFR-VFR. WILL HAVE VCSH IN THE TAFS FOR KGFL...KALB
AND KPSF AS CANNOT RULE OUT SNOW SHOWERS IN THE VICINITY AHEAD OF
AN ARCTIC FRONT WHICH WILL DROP SOUTHEASTWARD FROM CANADA TOWARD
OUR REGION ON SATURDAY.
SURFACE WINDS WILL NOT BE MUCH OF A FACTOR THIS TAF PERIOD. WINDS
WILL BE BE SOUTH OR SOUTHEAST AT 4 TO 8 KT AT TIMES...DIMINISHING TO
NEAR CALM TONIGHT...THEN SOUTH AT 6 KT OR LESS TOMORROW MORNING
AND SOUTHWEST AT 5 TO 10 KTS LATE SATURDAY AFTERNOON.
OUTLOOK...
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY-WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
THERE CONTINUES TO BE A SOLID SNOWPACK IN PLACE OVER MUCH OF THE
REGION. WHILE SNOW HAS THINNED SOMEWHAT FOR THE HUDSON VALLEY
REGION...ONE TO THREE FEET OF SNOW REMAINS IN THE HIGHER
ELEVATIONS. WITH COLD TEMPERATURES EXPECTED OVER THE NEXT FEW
DAYS...LITTLE MELTING OF THE SNOW WILL OCCUR.
ALTHOUGH THE FIRE WEATHER SEASON OFFICIALLY BEGAN ON MARCH
16TH...WIDESPREAD FIRE WEATHER CONCERNS WILL BE MINIMAL UNTIL
MELTING OF THE SNOW OCCURS. AS ALWAYS...SPOT FORECASTS ARE READILY
AVAILABLE IF REQUESTED.
&&
.HYDROLOGY...
WIDESPREAD HYDROLOGIC CONCERNS ARE NOT ANTICIPATED OVER THE NEXT
FIVE DAYS.
TEMPERATURES WILL BE BELOW FREEZING THIS EVENING INTO
TONIGHT...WITH LIGHT SNOW TAPERING OFF. HOWEVER...AHEAD OF AN
ARCTIC COLD FRONT...TEMPERATURES WILL BRIEFLY SPIKE INTO THE UPPER
30S TO MID 40S ACROSS THE REGION. SOME SNOW MELT WILL LIKELY
OCCUR ON SATURDAY AND A SOME LIGHT RAIN OR SNOW SHOWERS ARE
POSSIBLE WITH THE BOUNDARY...BUT AMOUNTS WILL BE VERY LIGHT.
COLDER AIR WILL QUICKLY RETURN TO THE REGION LATE SUNDAY WITH
MAINLY BELOW FREEZING TEMPS SATURDAY NIGHT THROUGH TUESDAY
MORNING. BY TUESDAY INTO WEDNESDAY...IT LOOKS TO REMAIN MAINLY
DRY...BUT DAYTIME TEMPERATURES WILL RISE ABOVE FREEZING INTO THE
40S. SOME MELTING WILL LIKELY OCCUR...AND RIVER TRACES WILL FOLLOW A
DIURNAL SNOWMELT PATTERN TYPICALLY SEEN IN THE EARLY SPRING.
DUE TO THE COLD TEMPERATURES IN PLACE...MELTING WILL BE LIMITED
THROUGH TUESDAY MORNING...ALTHOUGH THE SNOW AND ICE WILL CONTINUE
TO BE SLOWLY REDUCED DUE TO SUBLIMATION. WITH ONLY SMALL AMOUNTS
OF PRECIP EXPECTED AND LITTLE MELTING EXPECTED...ICE BREAKUP OR
ICE JAMS ARE NOT ANTICIPATED FOR MOST AREAS. HOWEVER...A SMALL ICE
JAM ON ANY SMALLER STREAMS FOR FAR SOUTHERN AREAS CANNOT BE RULED
OUT...BUT WIDESPREAD PROBLEMS ARE NOT EXPECTED THROUGH THE MIDDLE
OF THE UPCOMING WEEK.
AFTERWARD...WE WILL HAVE TO WATCH THE PROSPECTS FOR RAINFALL AND
SEE HOW WARM TEMPERATURES CAN RISE IN THE LATE WEEK PERIOD.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/11
SHORT TERM...FRUGIS
LONG TERM...ELH
AVIATION...11/NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
810 PM EDT FRI MAR 20 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM, TRACKING TO OUR SOUTH, WILL MOVE ALONG THE
COAST THEN TO OUR EAST THROUGH TONIGHT. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE SATURDAY INTO SATURDAY NIGHT. HIGH PRESSURE
WILL BUILD TOWARD THE AREA SUNDAY AND MOVE ACROSS THE AREA MONDAY
INTO TUESDAY, BEFORE SHIFTING EASTWARD INTO WEDNESDAY. A SLOW
MOVING COLD FRONT WILL CROSS THE REGION ON THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH THIS UPDATE, WE ARE GOING TO EXTEND THE ADVISORY INTO THE
OVERNIGHT OVER NORTHERN AND CENTRAL NEW JERSEY, MATCHING OKX`S
TIMING WITH THE POTENTIAL OF SOME AREAS OF LIGHT FREEZING RAIN
OR DRIZZLE.
0C AT 850MB ON THE RAP IS MATCHING THE CHANGE TO NON SNOW PRETTY
WELL AND SHOWING UP ON THE CC DUAL POL ALSO. WE CANCELED SOME
OF THE SOUTHERN ADVISORY COUNTIES, BUT WILL LET THE ADVISORY
REMAIN UP ELSEWHERE WHERE THE CHANGEOVER JUST OCCURRED AS ITS
TOO SOON AND FOR ANY RESIDUAL IMPACTS FOR THE COMMUTE HOME
WESTERN PART OF OUR CWA.
NO CHANGE FROM PREVIOUS THINKING AS WE ARE GETTING TO AROUND
WARNING CRITERIA ON NON PAVED SURFACES, BUT HALF OR EVEN
MORE THAN HALF AS MUCH ON PAVED SURFACES.
STILL, POWER OUTAGES ARE OCCURRING THOUGH WE ARE NOT SURE IF THEY
SNOW-TREE/WIRE RELATED.
COULD SEE A SITUATION IN SOME PLACES WITH 1.0 INCH ON PAVEMENT AND 6
INCHES ON GRASS. WE TRIED TO WORD THAT IN SOME OF OUR STATEMENTS.
YOU SEE THE RADAR WITH A NICE BAND BACK INTO E PA AND MOVING
ENE HEADING FOR KBLM. THE HEAVIEST AXIS...VCNTY KRDG - KBLM WITH
WIDESPREAD 5-6", POSSIBLY 7 INCH ON GRASS AND AROUND 2 ON PAVEMENT
THERE. POSSIBLE ISOLATED POWER OUTAGES LATE TODAY NEAR THIS AXIS.
PLEASE CONTINUE SENDING US YOUR ACCUM REPORTS, INCLUDING DIFFERENCE
FROM PAVEMENT TO YOUR NORMAL MEASURING SFC AND WHETHER ROADS ARE
BECOMING SLIPPERY. THANK YOU AGAIN FOR YOUR ASSISTANCE.
TONIGHT...ACCUMULATING SNOW CONTINUES PAST 8 PM NNJ OR NE NJ WHILE
SOUTH OF THAT, SOME RAIN/DRIZZLE, (POSSIBLE SPOTTY ICING SE PA).
OPTED NOT TO HIT THE FREEZING RAIN RISK TOO HARD AS AM NOT
CONFIDENT OF ITS OCCURRENCE.
IT SHOULD DRY OUT OVERNIGHT WITH TEMPS NEARLY STEADY MOST OF THE
NIGHT UNTIL IT PARTIALLY CLEARS TOWARD DAWN? PATCHY FOG MAY THICKEN
UP TOWARD DAWN BUT NOT COVERED IN THE FCST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE DAY SATURDAY INTO
SATURDAY NIGHT. THERE IS NOT A LOT OF MOISTURE/LIFT ASSOCIATED
WITH THE FRONT ACROSS OUR AREA AS THE MAIN MOISTURE/LIFT
ASSOCIATED WITH THE FRONT AND SHORT WAVE ALOFT PASS TO OUR NORTH.
HOWEVER, THERE MAY BE ENOUGH COMBINED LIFT AND MOISTURE FOR SOME
ISOLATED SHOWERS ACROSS NORTHWEST PORTIONS OF THE AREA LATE IN THE
DAY SATURDAY INTO SATURDAY EVENING AS THE SOUTHERN EDGE OF THE
SHORT WAVE MAY CLIP OUR NORTHERN AREAS, SO WE CONTINUED WITH
SLIGHT CHANCE POPS OVER THE POCONOS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
OVERVIEW...THE PERIOD STARTS WITH A COLD FRONT TRACKING NORTHWEST
TO SOUTHEAST THROUGH THE REGION. SURFACE HIGH PRESSURE BUILDS IN
ACROSS THE GREAT LAKES AND MID-ATLANTIC ON MONDAY. THE CENTER OF THE
HIGH SHIFTS FROM ONTARIO ON SUNDAY AFTERNOON, TO THE GREAT LAKES ON
MONDAY AFTERNOON, TO THE ATLANTIC SEABOARD ON TUESDAY AFTERNOON, AND
THEN OFF THE COAST ON WEDNESDAY. ON WEDNESDAY NIGHT, SURFACE LOW
PRESSURE ACROSS THE GREAT LAKES WILL BEGIN TO INTENSIFY. THE LOW IS
FORECAST TO MOVE NEAR MAINE ON FRIDAY EVENING. A WARM FRONT,
ATTACHED TO THE LOW WILL TRACK THROUGH THE REGION LATE ON WEDNESDAY.
A SLOW MOVING COLD FRONT WILL CROSS THE FORECAST AREA LATE ON
THURSDAY INTO FRIDAY.
IMPACTS...AS THE TODAY`S SNOW MELTS OVER THE WEEKEND, WE WILL SEE
CREEKS, STREAMS, AND RIVERS RISE A BIT. AS FOR OUR FORECAST POINTS,
PEMBERTON AND PINE BROOK MAY ONCE AGAIN RISE INTO CAUTION STAGE.
OTHER THAN THAT, THE EXTENDED PERIOD LOOKS FAIRLY BENIGN. THE PRECIP
WITH THE SATURDAY COLD FRONT ACROSS THE NORTH LOOKS LIGHT AND MAINLY
LIQUID. THE PRECIP WITH THE COLD FRONT ON THURSDAY LOOKS TO BE
HEAVIER COMPARED TO SATURDAY, BUT ALL LIQUID.
TEMPS...SLIGHTLY BELOW NORMAL ON SATURDAY, BELOW NORMAL SUNDAY THROUGH
TUESDAY, AROUND NORMAL FOR WEDNESDAY AND THURSDAY, AND AT OR BELOW
NORMAL FOR FRIDAY.
WINDS...NO SIGNIFICANT WIND ISSUES EXPECTED. NORTHWEST WINDS SHOULD
INCREASE BEHIND THE COLD FRONT SATURDAY NIGHT INTO SUNDAY. SOME
GUSTS IN THE 20-25 MPH RANGE POSSIBLE. SOUTHERLY/SOUTHWESTERLY WINDS
SHOULD INCREASE IN THE PRE-FRONTAL AIRMASS ON THURSDAY AND THEN GO
NORTHWEST ON FRIDAY. GUSTS, ONCE AGAIN, IN THE 20-25 MPG RANGE LOOKS
REASONABLE.
PRECIP...RAIN CHANCES INCREASE WEDNESDAY THROUGH FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE BACK EDGE OF THE STEADY PRECIPITATION IS CROSSING THE DEL VALLEY
AT 00Z TAF ISSUANCE TIME. IT DOES NOT APPEAR THAT CONDITIONS WILL
IMPROVE VERY RAPIDLY HOWEVER. MUCH OF THE GUIDANCE IS SHOWING
LIFR/IFR CONDITIONS TONIGHT AND CONTINUING INTO SAT MORNING. IT HAVE
GONE ALONG WITH IT FOR THE MOST PART SINCE THE WINDS IN THE LOW/MID
LEVELS WILL BE RATHER LIGHT AND THE DRY AIR IS STILL WELL TO THE
WEST/NORTH. VFR WILL RETURN TO THE N/W SITES BY LATE MORNING
SAT...THEN IMPROVEMENT FOR THE DEL VALLEY DURING THE AFTERNOON.
WINDS WILL BE A BIT GUSTY THIS EVENING FROM THE NE OR N THEN SHIFT
TO NW AND BECOME LIGHTER OVERNIGHT.
OUTLOOK...
SATURDAY NIGHT...A COLD FRONT WILL TRACK ACROSS THE TERMINALS.
SCATTERED SHOWERS ARE POSSIBLE ACROSS THE NORTHERN TERMINALS. VFR
IS EXPECTED, EXCEPT A TEMPO MVFR POSSIBLE IN A SHOWER. HIGH
CONFIDENCE.
SUNDAY-TUESDAY...VFR UNDER HIGH PRESSURE. GUSTY NORTHWEST WINDS
AROUND 20 KT ARE POSSIBLE SATURDAY NIGHT AND SUNDAY. HIGH CONFIDENCE.
WEDNESDAY...VFR CONTINUES AS THE SURFACE HIGH SHIFTS OFFSHORE. HIGH
CONFIDENCE.
&&
.MARINE...
WE ARE ISSUING A SHORT FUSED GALE AS GALE FORCE GUSTS ARE POSSIBLE
UNTIL AROUND MIDNIGHT FROM COASTAL OCEAN COUNTY SOUTHWARD
ALONG THE OCEAN. REMAINING MARINE FLAGS STAY AS IS.
OUTLOOK... SATURDAY NIGHT...SCA SEAS MAY PERSIST INTO SATURDAY
EVENING ON THE OCEAN, OTHERWISE NO HEADLINES EXPECTED. A COLD
FRONT IS FORECAST TO TRACK OFF THE COAST SATURDAY NIGHT.
SUNDAY THROUGH WEDNESDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED. HIGH CONFIDENCE THROUGH THE PERIOD WITH THE EXCEPTION OF
EARLY SUNDAY WHERE, AS OF NOW, WINDS ARE FORECAST UP TO 20 KT.
SURFACE HIGH PRESSURE WILL DOMINATE THE 4 DAY PERIOD, MOVING FROM
THE INTERIOR TO OFF THE COAST.
&&
.CLIMATE...
SNOW WHILE SIGNIFICANT ACROSS A LARGE PORTION OF OUR AREA, IS NOT
EXPECTED TO EXCEED RECORD VALUES.
FOR PERSPECTIVE: MARCH 20 DAILY RECORD SNOWFALL VALUES FOLLOW
1958 WAS THE YEAR.
KABE 16.5 - 1958
KACY 5.0 - 1958
KILG 10.3 - 1958
KPHL 9.6 - 1958
LATEST OCCURRENCE OF MEASURABLE SNOW AND AMOUNT DURING THE
2013-2014 WINTER FOLLOWS...
KABE - 4/15/14 0.3"
KACY - 3/16/14 0.3"
(NOTE: LATEST OCCURRENCE ON RECORD IS 4/24/56 0.4")
KPHL - 3/25/14 0.4"
KILG - 3/25/14 0.7"
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
PAZ054-055-060>062-070-071-101>106.
NJ...WINTER WEATHER ADVISORY UNTIL 2 AM EDT SATURDAY FOR NJZ001-
007>010-012>015-019-020-026-027.
WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
NJZ017-018.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 2 AM EDT SATURDAY FOR ANZ451>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ450.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ431.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO/O`HARA
MARINE...GIGI/KRUZDLO
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
735 PM EDT FRI MAR 20 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM, TRACKING TO OUR SOUTH, WILL MOVE ALONG THE
COAST THEN TO OUR EAST THROUGH TONIGHT. A COLD FRONT WILL MOVE
ACROSS THE AREA LATE SATURDAY INTO SATURDAY NIGHT. HIGH PRESSURE
WILL BUILD TOWARD THE AREA SUNDAY AND MOVE ACROSS THE AREA MONDAY
INTO TUESDAY, BEFORE SHIFTING EASTWARD INTO WEDNESDAY. A SLOW
MOVING COLD FRONT WILL CROSS THE REGION ON THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH THIS UPDATE, WE ARE GOING TO EXTEND THE ADVISORY INTO THE
OVERNIGHT OVER NORTHERN AND CENTRAL NEW JERSEY, MATCHING OKX`S
TIMING WITH THE POTENTIAL OF SOME AREAS OF LIGHT FREEZING RAIN
OR DRIZZLE.
0C AT 850MB ON THE RAP IS MATCHING THE CHANGE TO NON SNOW PRETTY
WELL AND SHOWING UP ON THE CC DUAL POL ALSO. WE CANCELED SOME
OF THE SOUTHERN ADVISORY COUNTIES, BUT WILL LET THE ADVISORY
REMAIN UP ELSEWHERE WHERE THE CHANGEOVER JUST OCCURRED AS ITS
TOO SOON AND FOR ANY RESIDUAL IMPACTS FOR THE COMMUTE HOME
WESTERN PART OF OUR CWA.
NO CHANGE FROM PREVIOUS THINKING AS WE ARE GETTING TO AROUND
WARNING CRITERIA ON NON PAVED SURFACES, BUT HALF OR EVEN
MORE THAN HALF AS MUCH ON PAVED SURFACES.
STILL, POWER OUTAGES ARE OCCURRING THOUGH WE ARE NOT SURE IF THEY
SNOW-TREE/WIRE RELATED.
COULD SEE A SITUATION IN SOME PLACES WITH 1.0 INCH ON PAVEMENT AND 6
INCHES ON GRASS. WE TRIED TO WORD THAT IN SOME OF OUR STATEMENTS.
YOU SEE THE RADAR WITH A NICE BAND BACK INTO E PA AND MOVING
ENE HEADING FOR KBLM. THE HEAVIEST AXIS...VCNTY KRDG - KBLM WITH
WIDESPREAD 5-6", POSSIBLY 7 INCH ON GRASS AND AROUND 2 ON PAVEMENT
THERE. POSSIBLE ISOLATED POWER OUTAGES LATE TODAY NEAR THIS AXIS.
PLEASE CONTINUE SENDING US YOUR ACCUM REPORTS, INCLUDING DIFFERENCE
FROM PAVEMENT TO YOUR NORMAL MEASURING SFC AND WHETHER ROADS ARE
BECOMING SLIPPERY. THANK YOU AGAIN FOR YOUR ASSISTANCE.
TONIGHT...ACCUMULATING SNOW CONTINUES PAST 8 PM NNJ OR NE NJ WHILE
SOUTH OF THAT, SOME RAIN/DRIZZLE, (POSSIBLE SPOTTY ICING SE PA).
OPTED NOT TO HIT THE FREEZING RAIN RISK TOO HARD AS AM NOT
CONFIDENT OF ITS OCCURRENCE.
IT SHOULD DRY OUT OVERNIGHT WITH TEMPS NEARLY STEADY MOST OF THE
NIGHT UNTIL IT PARTIALLY CLEARS TOWARD DAWN? PATCHY FOG MAY THICKEN
UP TOWARD DAWN BUT NOT COVERED IN THE FCST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE DAY SATURDAY INTO
SATURDAY NIGHT. THERE IS NOT A LOT OF MOISTURE/LIFT ASSOCIATED
WITH THE FRONT ACROSS OUR AREA AS THE MAIN MOISTURE/LIFT
ASSOCIATED WITH THE FRONT AND SHORT WAVE ALOFT PASS TO OUR NORTH.
HOWEVER, THERE MAY BE ENOUGH COMBINED LIFT AND MOISTURE FOR SOME
ISOLATED SHOWERS ACROSS NORTHWEST PORTIONS OF THE AREA LATE IN THE
DAY SATURDAY INTO SATURDAY EVENING AS THE SOUTHERN EDGE OF THE
SHORT WAVE MAY CLIP OUR NORTHERN AREAS, SO WE CONTINUED WITH
SLIGHT CHANCE POPS OVER THE POCONOS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
OVERVIEW...THE PERIOD STARTS WITH A COLD FRONT TRACKING NORTHWEST
TO SOUTHEAST THROUGH THE REGION. SURFACE HIGH PRESSURE BUILDS IN
ACROSS THE GREAT LAKES AND MID-ATLANTIC ON MONDAY. THE CENTER OF THE
HIGH SHIFTS FROM ONTARIO ON SUNDAY AFTERNOON, TO THE GREAT LAKES ON
MONDAY AFTERNOON, TO THE ATLANTIC SEABOARD ON TUESDAY AFTERNOON, AND
THEN OFF THE COAST ON WEDNESDAY. ON WEDNESDAY NIGHT, SURFACE LOW
PRESSURE ACROSS THE GREAT LAKES WILL BEGIN TO INTENSIFY. THE LOW IS
FORECAST TO MOVE NEAR MAINE ON FRIDAY EVENING. A WARM FRONT,
ATTACHED TO THE LOW WILL TRACK THROUGH THE REGION LATE ON WEDNESDAY.
A SLOW MOVING COLD FRONT WILL CROSS THE FORECAST AREA LATE ON
THURSDAY INTO FRIDAY.
IMPACTS...AS THE TODAY`S SNOW MELTS OVER THE WEEKEND, WE WILL SEE
CREEKS, STREAMS, AND RIVERS RISE A BIT. AS FOR OUR FORECAST POINTS,
PEMBERTON AND PINE BROOK MAY ONCE AGAIN RISE INTO CAUTION STAGE.
OTHER THAN THAT, THE EXTENDED PERIOD LOOKS FAIRLY BENIGN. THE PRECIP
WITH THE SATURDAY COLD FRONT ACROSS THE NORTH LOOKS LIGHT AND MAINLY
LIQUID. THE PRECIP WITH THE COLD FRONT ON THURSDAY LOOKS TO BE
HEAVIER COMPARED TO SATURDAY, BUT ALL LIQUID.
TEMPS...SLIGHTLY BELOW NORMAL ON SATURDAY, BELOW NORMAL SUNDAY THROUGH
TUESDAY, AROUND NORMAL FOR WEDNESDAY AND THURSDAY, AND AT OR BELOW
NORMAL FOR FRIDAY.
WINDS...NO SIGNIFICANT WIND ISSUES EXPECTED. NORTHWEST WINDS SHOULD
INCREASE BEHIND THE COLD FRONT SATURDAY NIGHT INTO SUNDAY. SOME
GUSTS IN THE 20-25 MPH RANGE POSSIBLE. SOUTHERLY/SOUTHWESTERLY WINDS
SHOULD INCREASE IN THE PRE-FRONTAL AIRMASS ON THURSDAY AND THEN GO
NORTHWEST ON FRIDAY. GUSTS, ONCE AGAIN, IN THE 20-25 MPG RANGE LOOKS
REASONABLE.
PRECIP...RAIN CHANCES INCREASE WEDNESDAY THROUGH FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE BACK EDGE OF THE STEADY PRECIPITATION IS CROSSING THE DEL VALLEY
AT 00Z TAF ISSUANCE TIME. IT DOES NOT APPEAR THAT CONDITIONS WILL
IMPROVE VERY RAPIDLY HOWEVER. MUCH OF THE GUIDANCE IS SHOWING
LIFR/IFR CONDITIONS TONIGHT AND CONTINUING INTO SAT MORNING. IT HAVE
GONE ALONG WITH IT FOR THE MOST PART SINCE THE WINDS IN THE LOW/MID
LEVELS WILL BE RATHER LIGHT AND THE DRY AIR IS STILL WELL TO THE
WEST/NORTH. VFR WILL RETURN TO THE N/W SITES BY LATE MORNING
SAT...THEN IMPROVEMENT FOR THE DEL VALLEY DURING THE AFTERNOON.
WINDS WILL BE A BIT GUSTY THIS EVENING FROM THE NE OR N THEN SHIFT
TO NW AND BECOME LIGHTER OVERNIGHT.
OUTLOOK...
SATURDAY NIGHT...A COLD FRONT WILL TRACK ACROSS THE TERMINALS.
SCATTERED SHOWERS ARE POSSIBLE ACROSS THE NORTHERN TERMINALS. VFR
IS EXPECTED, EXCEPT A TEMPO MVFR POSSIBLE IN A SHOWER. HIGH
CONFIDENCE.
SUNDAY-TUESDAY...VFR UNDER HIGH PRESSURE. GUSTY NORTHWEST WINDS
AROUND 20 KT ARE POSSIBLE SATURDAY NIGHT AND SUNDAY. HIGH CONFIDENCE.
WEDNESDAY...VFR CONTINUES AS THE SURFACE HIGH SHIFTS OFFSHORE. HIGH
CONFIDENCE.
&&
.MARINE...
SCA CONTINUES AS POSTED. MAY NEED A SLIGHT UPWARD ADJUSTMENT LATE
THIS EVENING FOR A SMALL CHANCE BRIEF GALE CONDITIONS ON THE ATLC
WATERS ONLY (CENTRAL NJ TO DE COASTS) IN THE 6 PM TO 10 PM EDT
TIME FRAME.
OUTLOOK...
SATURDAY NIGHT...SCA SEAS MAY PERSIST INTO SATURDAY EVENING ON THE
OCEAN, OTHERWISE NO HEADLINES EXPECTED. A COLD FRONT IS FORECAST TO
TRACK OFF THE COAST SATURDAY NIGHT.
SUNDAY THROUGH WEDNESDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED. HIGH CONFIDENCE THROUGH THE PERIOD WITH THE EXCEPTION OF
EARLY SUNDAY WHERE, AS OF NOW, WINDS ARE FORECAST UP TO 20 KT.
SURFACE HIGH PRESSURE WILL DOMINATE THE 4 DAY PERIOD, MOVING FROM
THE INTERIOR TO OFF THE COAST.
&&
.CLIMATE...
SNOW WHILE SIGNIFICANT ACROSS A LARGE PORTION OF OUR AREA, IS NOT
EXPECTED TO EXCEED RECORD VALUES.
FOR PERSPECTIVE: MARCH 20 DAILY RECORD SNOWFALL VALUES FOLLOW
1958 WAS THE YEAR.
KABE 16.5 - 1958
KACY 5.0 - 1958
KILG 10.3 - 1958
KPHL 9.6 - 1958
LATEST OCCURRENCE OF MEASURABLE SNOW AND AMOUNT DURING THE
2013-2014 WINTER FOLLOWS...
KABE - 4/15/14 0.3"
KACY - 3/16/14 0.3"
(NOTE: LATEST OCCURRENCE ON RECORD IS 4/24/56 0.4")
KPHL - 3/25/14 0.4"
KILG - 3/25/14 0.7"
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
PAZ054-055-060>062-070-071-101>106.
NJ...WINTER WEATHER ADVISORY UNTIL 2 AM EDT SATURDAY FOR NJZ001-
007>010-012>015-019-020-026-027.
WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
NJZ017-018.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ431.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...KRUZDLO
AVIATION...KRUZDLO/O`HARA
MARINE...DRAG/KRUZDLO
CLIMATE...
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
900 AM EDT THU MAR 19 2015
.DISCUSSION... UA DATA FROM THE CANAVERAL SOUNDING SHOWS PRESENCE OF
A PARTIALLY BUOYANT AIRMASS THAT SHOULD BE ABLE TO OVERCOME MODEST
INHIBITION DURING THE COURSE OF THE AFTERNOON. CONSIDERABLE HIGHER
CLOUDS WL DELAY HEATING SOMEWHAT. ISOLD MARINE SHOWERS THIS MORNING
WL TRANSITION TO THE COAST WITH SOME ADTL DEVELOPMENT INLAND AS A
BREEZE BOUNDARY SETS UP FROM EARLY AFTN ONWARD. LTST HRRR GUID SHOWS
SOME DEVELOPMENT OF ECSB BOUNDARY RELATED PCPN WEST OF I-95 EARLY IN
AFTERNOON WITH ANOTHER ROUND OF EARLY EVENING DEVELOPMENT OF
SCT/ISOLD SHOWERS W OF METRO ORLANDO DUE TO A BREEZE COLLISION
TOWARD DUSK. NO FORECAST UPDATE PLANNED ATTM.
TODAY/TONIGHT...(PREV DISC) WEAK FRONTAL BOUNDARY OVER THE REGION
WILL LIFT NORTHWARD LATER TODAY INTO TONIGHT AS MID LEVEL S/W
CROSSING THE DEEP SOUTH DEVELOPS A WEAK LOW OFF THE SOUTHEAST U.S.
COAST. LOW LEVEL E/SE FLOW WILL BECOME MORE SOUTHERLY INTO THE AFT
AS THIS BOUNDARY LIFTS NORTH WITH SOME INCREASE IN MOISTURE
EXPECTED. FLOW WILL BE LIGHT ENOUGH FOR SEA BREEZE BOUNDARIES TO
DEVELOP AND MOVE INLAND INITIATING ISO/SCT SHOWERS ACROSS THE AREA.
BEST RAIN CHANCES (UP TO 30-40%) WILL EXIST FROM OSCEOLA/NRN BREVARD
COUNTY NORTHWARD WHERE GREATER MOISTURE EXISTS AND WHERE ENHANCED
SUPPORT FOR LIFT WILL RESIDE FROM PASSING S/W AND A LATE DAY SEA
BREEZE COLLISION ACROSS THE INTERIOR. RAIN CHANCES THEN DECREASE
INTO THE EVENING AND END OVER THE REGION BY MIDNIGHT.
&&
.AVIATION...FOG/STRATUS SHOULD BURN OFF BY MID MORNING WITH VFR
CONDS GENERALLY EXPECTED THROUGH THE DAY. ISO/SCT SHRA WILL BE
POSSIBLE ALONG THE INLAND MOVING EAST COAST SEA BREEZE INTO THE AFT
WITH BEST CHANCES ACROSS NRN TERMINALS WHERE BETTER MOISTURE WILL
RESIDE. PATCHY FOG PRODUCING IFR/MVFR CONDS WILL ONCE AGAIN BE
POSSIBLE LATE TONIGHT.
&&
.MARINE...
TODAY/TONIGHT...WEAK FRONTAL BOUNDARY OVER THE AREA WILL EVENTUALLY
LIFT NORTHWARD LATER TODAY INTO TONIGHT. ONSHORE WINDS UP TO 15-20
KNOTS OVER THE OFFSHORE WATERS NORTH OF THE CAPE WILL SLOWLY
DECREASE AS FLOW VEERS TO THE SOUTHEAST AND EVENTUALLY SOUTH TO
SOUTHWEST INTO TONIGHT.
WNAWAVE GUIDANCE CONTINUES TO BE OVERESTIMATING WAVE HEIGHTS BY A
FOOT SO HAVE LIMITED SEAS OFFSHORE TO 6 FEET. WILL KEEP SMALL CRAFT
EXERCISE CAUTION HEADLINES FOR THESE POOR BOATING CONDS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
JP/TES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
244 PM CDT THU MAR 19 2015
.SHORT TERM...
243 PM CDT
THROUGH SATURDAY...
MAIN FORECAST CONCERNS IN THE NEAR TERM INCLUDE PRECIP CHANCES IN
OUR SOUTHERN COUNTIES TONIGHT...AND A COLD FRONT WHICH WILL BRING
FALLING TEMPERATURES DURING THE DAY SATURDAY...
RADAR IMAGERY SHOWS AREA OF PRECIPITATION ACROSS PORTIONS OF
NORTHERN MISSOURI AND WEST CENTRAL ILLINOIS THIS AFTERNOON
ASSOCIATED WITH AN AREA OF WARM ADVECTION AND BROAD MID-LEVEL
HEIGHT FALLS IN ADVANCE OF A LOW AMPLITUDE WAVE. THIS AREA WILL
SPREAD ENE ACROSS PORTIONS OF MAINLY CENTRAL ILLINOIS THIS EVENING
AND TONIGHT...WITH THE BEST CHANCES FOR PRECIP STAYING SOUTH OF
I-80 IN THE LOCAL FORECAST AREA. EXPECT THE ENTIRE FORECAST AREA
TO BE DRY ON FRIDAY AS SUBSIDENCE OVERSPREADS THE REGION BEHIND
THE DEPARTING UPPER TROUGH. DOWN LOW...WINDS TURN SOUTHWEST IN
ADVANCE OF OUR NEXT SYSTEM HELPING TO ADVECT IN WARMER
TEMPERATURES. MID TO UPPER 50S ARE EXPECTED FRIDAY AFTERNOON.
SOUTHWEST FLOW SHOULD REMAIN STRONG ENOUGH TO PREVENT A LAKE
BREEZE FROM MAKING MUCH IF ANY INLAND PROGRESS TOMORROW.
MEANWHILE...LOW PRESSURE TRACKING ACROSS HUDSON BAY INTO THE
CANADIAN MARITIME PROVINCES TOMORROW WILL DRAG A COLD FRONT INTO
THE NORTHERN GREAT LAKES REGION WITH A WAVE FORMING ALONG THE
FRONT IN THE UPPER MIDWEST AS ANOTHER SHORTWAVE TROUGH DIVES INTO
THE NORTHERN TIER OF STATES. PRECIPITATION WITH THIS SYSTEM SHOULD
REMAIN WELL TO OUR NORTH WITH PRETTY DRY CONDITIONS NOTED IN THE
SOUNDINGS LOCALLY. DO EXPECT HOWEVER THAT THE COLD AIR BEHIND THE
FRONT WILL SURGE DOWN LAKE MICHIGAN PUSHING INTO NORTHERN ILLINOIS
EARLY IN THE DAY SATURDAY RESULTING IN EARLY HIGH TEMPS AND
FALLING TEMPS OFF THE LAKE BY AROUND MIDDAY.
DEUBELBEISS
&&
.LONG TERM...
243 PM CDT
SATURDAY NIGHT THROUGH THURSDAY...
RIDGE OF HIGH PRESSURE WILL BE IN PLACE JUST TO OUR NORTH SATURDAY
NIGHT INTO SUNDAY WITH A WEAK SURFACE LOW OVER THE CENTRAL PLAINS
AND THE LOCAL FORECAST AREA JUST ON THE COLD SIDE OF THE H85
BAROCLINIC ZONE. OVERNIGHT LOWS SHOULD FALL BELOW FREEZING AREA
WIDE SATURDAY NIGHT WITH TEMPERATURES ONLY REBOUNDING INTO THE 40S
SUNDAY. ISENTROPIC ASCENT INCREASES THROUGH THE DAY SUNDAY FOCUSED
FROM SOUTHERN MINNESOTA INTO NORTHERN ILLINOIS. WITH ANTECEDENT
DRY LOW LEVELS AND DRY NORTHEASTERLY FLOW ALSO IN THE LOW
LEVELS...LEANING TOWARDS SLOWER GUIDANCE AS FAR AS OSNET OF
PRECIPITATION SO EXPECT SUNDAY TO BE DRY ACROSS THE FORECAST AREA
WITH PRECIP CHANCES INCREASING FROM THE NORTHWEST LATE SUNDAY
NIGHT INTO MONDAY AS A COMPACT VORT MAX DROPS INTO THE MIDWEST.
DESPITE SURFACE TEMPERATURES EVENTUALLY RISING INTO THE MID TO
UPPER 30S MONDAY...THE DEPTH OF THE NEAR SURFACE WARM LAYER MAY BE
TOO SHALLOW FOR COMPLETE MELTING SO EXPECT PRECIPITATION TO
PRIMARILY FALL AS SNOW. LIGHT ACCUMULATIONS APPEAR POSSIBLE
HOWEVER DIFFERENCES IN THE TRACK PRECLUDE NAILING DOWN ANY OF THE
DETAILS THIS FAR OUT...BUT WOULD PROBABLY ERR ON THE DRIER SIDE
GIVEN SOME OF THE AFOREMENTIONED CONCERNS ABOUT MOISTURE
AVAILABILITY AND SATURATION CONCERNS.
CONTINUE TO MONITOR THE POSSIBILITY OF A MORE DYNAMIC SYSTEM
IMPACTING THE REGION TUESDAY AND WEDNESDAY WITH MODELS CONTINUING TO
ADVERTISE AT LEAST A BRIEF WARMUP THANKS TO 50KT+ LOW LEVEL JET
TRANSPORTING +10C 850MB TEMPS AND PWATS JUST IN EXCESS OF AN INCH
INTO PORTIONS OF THE UPPER MIDWEST. LATEST GFS AND ECMWF BOTH SHOW
THE THERMAL AXIS MOVING ACROSS NORTHERN ILLINOIS TUESDAY NIGHT.
BASED ON CURRENT TIMING OFF THE ECMWF AND GFS...WOULD EXPECT WARMING
TEMPS TUESDAY NIGHT AND CONSERVATIVELY MID TO UPPER 50S
WEDNESDAY...THOUGH GUIDANCE MAY BE UNDER-FORECASTING THE WARMUP.
PRECIPITATION...CLOUD COVER...AND TIMING OF THE COLD FRONT WILL
LIKELY BE LIMITING FACTORS BUT CLIMATOLOGY SUGGESTS WE COULD EASILY
BE ABLE TO GET INTO THE 60S WEDNESDAY. COLD FRONT EVENTUALLY SWEEPS
BACK ACROSS THE REGION MIDWEEK WITH WELL BELOW NORMAL CONDITIONS
RETURNING THE LATTER HALF OF NEXT WEEK.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIND SPEEDS AND DIRECTIONS THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
WINDS HAVE BEEN THE CHALLENGE TODAY...GOING A BIT EARLIER THAN
EXPECTED TO STRONGER SPEEDS AND A MORE EASTERLY DIRECTION THIS
MORNING...AND THEN VEERING SOUTHEASTERLY AGAIN BY EARLY
AFTERNOON WHILE INCREASING FURTHER. SPEEDS ARE EXPECTED TO RELAX
SOMEWHAT THIS AFTERNOON BUT THE DIRECTION MAY AGAIN TURN MORE
EASTERLY IF A LAKE BREEZE INFLUENCE DEVELOPS...SO GETTING BACK TO
A MORE FAVORABLE CONFIGURATION AT ORD MAY HAVE TO WAIT UNTIL LATER
THIS EVENING...PROBABLY AFTER THE PEAK RUSH.
ALSO MAINTAINED THE MENTION OF SHRA FOR LATER THIS EVENING BUT GIVEN
THE DRY AIR IN PLACE TODAY IT COULD BE HARD TO GET MORE THAN SOME
SPRINKLES OR BRIEF LIGHT RAIN SHOWERS.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM FOR WIND AND LOW FOR SHRA CHANCES BUT OTHERWISE HIGH.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
203 PM CDT
AS HIGH PRESSURE CONTINUES TO MOVE FROM THE EASTERN GREAT LAKES TO
THE EAST...GENERALLY SELY HAS DEVELOPED OVER LAKE MICHIGAN. A WEAK
GRADIENT OVER THE SOUTHERN PORTIONS OF THE LAKE HAVE ALLOWED A
PSEUDO-LAKE BREEZE TO DEVELOP WITH WINDS MORE ELY OVER THE NEARSHORE
WATERS ALONG THE ILLINOIS COAST...WHILE WINDS REMAIN SELY OVER THE
INDIANA NEARSHORE WATERS. AS THE HIGH CONTINUES TO THE EAST TONIGHT
AND LOW PRESSURE TRACKS ACROSS THE CANADIAN PRAIRIES...WITH A
TRAILING COLD FRONT EXTENDING INTO THE NRN PLAINS...WINDS WILL VEER
TO SOUTHERLY BY FRIDAY MORNING. THE COMBINATION OF A SLOW MOVING
HIGH MOVING OFF TO THE EAST AND A FASTER MOVING SFC TROUGH AND
ASSOCIATED COLD FRONT FROM THE WEST...WILL LEAD TO STRENGTHENING
SLY WINDS THROUGH FRIDAY INTO FRIDAY EVENING WITH SPEEDS INCREASING
TO 20-25KT...WITH THE STRONGEST WINDS OVER THE NRN PORTIONS OF THE
LAKE WHERE THE GRADIENT WILL BE STRONGEST. THE COLD FRONT IS
EXPECTED TO PUSH SOUTH DOWN THE LAKE LATE FRIDAY NIGHT...INTO
SATURDAY MORNING...TURNING WINDS MORE NORTHERLY AND DRAWING COLDER
AIR DOWN THE LAKE. THE INCREASING COLD ADVECTION AS ANOTHER ARCTIC
HIGH BUILDS OUT OF CANADA AND INTO THE UPPER MISSISSIPPI VALLEY AND
WESTERN GREAT LAKES SHOULD HELP BRING THE NORTHERLY WINDS BACK UP TO
20-25KT SATURDAY NIGHT AND INTO SUNDAY. WHILE GALES ARE NOT
EXPECTED FOLLOWING THE FRONTAL PASSAGE...THE EXTENDED NORTHERLY
FETCH SHOULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS FOR BOTH THE
ILLINOIS AND INDIANA NEARSHORE WATERS FOR SATURDAY NIGHT AND SUNDAY.
WINDS WILL GRADUALLY VEER TO NORTHEASTERLY TO EASTERLY SUNDAY NIGHT
AND MONDAY AS THE HIGH BUILDS ACROSS THE EASTERN GREAT LAKES AND
WEAK LOW PRESSURE DEVELOPING OVER THE CENTRAL PLAINS SUNDAY TRACKS
EAST TO THE LOWER OHIO VALLEY BEFORE WEAKENING TO AN OPEN TROUGH
EXTENDING FROM TENNESSEE TO WESTERN PENNSYLVANIA EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
211 PM CDT Thu Mar 19 2015
.SHORT TERM...(Tonight)
ISSUED AT 209 PM CDT THU MAR 19 2015
Area of rain across Missouri has spread into west central Illinois
early this afternoon, with some light rain being reported as far
east as Jacksonville at 2 pm. Still quite a bit of dry air
underneath this rain, with temp/dew point spreads around 15 degrees,
so amounts will remain rather light this afternoon. Latest HRRR and
NAM spread this eastward centered along the Jacksonville-Paris
corridor through the afternoon, reaching the Indiana border toward
4-5 pm., with a southern extent generally along I-70. Any northward
extension past Peoria would be more likely very late afternoon. The
bulk of the precipitation should be east of the forecast area by
around midnight or so, but some drizzle is likely to linger
overnight, especially in the south half of the forecast area, where
stratus should become extensive after midnight. Little change made
to the temperatures, with lows 35-38 in most areas.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 209 PM CDT THU MAR 19 2015
Split-flow pattern continues into the end of the week as deep trough
continues to pivot over the Hudson Bay area and southern stream
energy moves slowly over the southwest U.S.. Wave embedded in the
northern stream trough should exit the forecast area Friday bringing
gradual clearing and seasonal temperatures.
Next northern stream wave and associated cold front is expected to
impact the area on Saturday. Significant spread on frontal passage
timing is evident in operational model suite and SREF which has
major implications on temperatures for Saturday, particularly across
the central forecast area. Northern tier of area see passage before
peak heating in most of the solutions with I-70 southward not
impacted by cold advection until well after peak heating through the
solution envelope. Its the I-72/Danville corridor which has the
largest impact of this difference in timing. Operational 12Z NAM is
slow enough to suggest some lower 70s are possible across southwest
forecast area, however, the model seems to be on the warm side of the
SREF envelope. For now will be leaning toward the cooler, but still
above normal, GFS/SREF Mean timing. Either way, moisture remains
shunted south and east of Illinois so passage will be dry.
Much cooler temperatures will move into the region behind the front
with progged 850 mb temps expected below freezing across the
northern half of the area by Monday.
Models are suggesting a temporary transition to a more progressive
zonal pattern by early next week. The initial wave in this pattern
shift is progged to move eastward into Illinois Monday. Low-level
temperatures remain cool and Bufkit soundings suggest a mix of
precip may be possible late Sunday Night and early Monday across
northern portions of the forecast area. The southern stream energy
moving across the southern tier of the country is expected to be
over the eastern Gulf of Mexico by Sunday Night shunting any Gulf
moisture east limiting moisture available in the Midwest, so QPF
will likely be limited to a few tenths of liquid at most.
Phased ridging develops over the Mississippi Valley by Tuesday
allowing temps to respond rapidly. With the phasing, Gulf moisture
is available for the next wave expected to push into the state on
Wednesday. Latest model suite are fairly consistent on bringing 850
temps into the 10C range with surface dew points into the 50s.
Timing of the waves associated cold front will have an impact on any
potential instability and if a passage does occur near peak heating
can not rule out the potential for thunder, particularly across
southeast Illinois Wednesday afternoon and evening.
At this time, GFS and ECMWF suggest the strong wave on Wednesday
will assist in a transition back to a ridge west/trough east
longwave pattern allowing cold air to once again plummet into the
midwest. With 850 mb temps expected to be below 0C by Thursday
afternoon, highs on Thursday may struggle to make it out of the 40s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1230 PM CDT THU MAR 19 2015
Main forecast issue will be with development of MVFR/IFR
conditions later this afternoon and evening. MVFR ceilings
spreading toward the IL/MO border with IFR conditions underneath
the rain further west in Missouri. Some moistening of the lower
levels of the atmosphere will need to take place as the
precipitation arrives in central Illinois over the next few hours,
so current thinking is that ceilings below 3,000 feet will start
moving into KPIA/KSPI after 22-23Z and encompassing the remaining
TAF sites this evening. Have introduced some IFR ceilings from
KSPI-KCMI overnight, becoming more widespread as the rain exits in
the 05-09Z time frame. Further north, have kept KPIA/KBMI as MVFR
overnight. Some clearing should begin Friday morning from the
northwest, but a passing upper trough will likely keep MVFR
ceilings in much of central Illinois through a good part of the
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Barker
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1241 PM CDT THU MAR 19 2015
.SHORT TERM...
325 AM CDT
TODAY AND TONIGHT...
MAIN FORECAST CHALLENGES ARE WITH PRECIP TRENDS THIS EVENING
THROUGH THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN THIRD OF
THE CWA WITH PRIMARILY RAIN EXPECTED...BUT WITH THE POSSIBILITY
FOR A BRIEF WINDOW OF A RAIN SNOW MIX.
QUIET CONDITIONS IN THE NEAR TERM AS HIGH PRESSURE SPANS THE
GREAT LAKES REGION. MID/HIGH CLOUDS CONTINUE TO SPREAD OVERHEAD
FROM BOTH THE SOUTHERN STREAM ENERGY AND APPROACHING MID LEVEL
TROUGH OVER THE NORTHERN PLAINS. CURRENT CLOUDY CONDITIONS WILL
REMAIN POSSIBLY BRIEFLY THINNING AT TIMES FOR A TIME THIS
MORNING...BUT WITH INCREASING CLOUDS EXPECTED ONCE AGAIN THROUGH
MIDDAY. DESPITE CLOUDS IN PLACE...HIGHS AROUND 50 ARE EXPECTED
TODAY WITH SLIGHTLY COOLER CONDITIONS IN THE LOW TO MID 40S NEAR
THE LAKE.
THE BULK OF THE PRECIP THIS MORNING REMAINS WELL SOUTH OF THE
AREA OVER THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY. GUIDANCE
CONTINUES TO SHOW THAT THIS PRECIP WILL BLOSSOM FURTHER NORTH
LATER THIS AFTERNOON AND EARLY EVENING. THIS WILL BE IN RESPONSE
TO PERSISTENT SHORT WAVE ENERGY...WAA...AND BETTER LARGE SCALE
SUPPORT WITH APPROACHING TROUGH FROM THE NORTHWEST. HOWEVER...IT
DOES APPEAR THAT THIS WILL BE FOCUSED MORE ALONG THE SOUTHERN
THIRD OF THE CWA WITH THE FAR SOUTHERN TIER HAVING THE BEST
CHANCE. DID INCLUDE LIKELY POPS IN THIS LOCATION WITH CHANCE TO
SLIGHT CHANCE POPS FURTHER NORTH...JUST NORTH OF THE I80 CORRIDOR.
PRECIP WILL LIKELY STAY ALONG AND SOUTH OF I80 BUT WITH GUIDANCE
STILL VARYING TO THE NORTHERN EXTENT OF THIS PRECIP
SHIELD...WANTED TO KEEP AT LEAST SLIGHT CHANCE POPS SLIGHTLY
FURTHER NORTH. TIMING APPEARS TO BE FROM EARLY EVENING TO LATE
EVENING WITH IT THEN EXITING AFTER THE MIDNIGHT TIME FRAME.
THERMAL PROFILES SUGGEST ALL RAIN OVER THE ENTIRE CWA BUT IT DOES
LOOK LIKE THERE COULD BE A PERIOD WHEN SOME LOCATIONS COULD
OBSERVE A BRIEF WINDOW OF A RAIN SNOW MIX. HOWEVER...NOT OVERLY
EXCITED WITH THIS POSSIBILITY AND HAVE LEFT OUT ANY MENTION OF
SNOW IN THE GRIDS. LOW TEMPS TONIGHT WILL BE IN THE MID TO UPPER
30S...AND AM NOT CONCERNED WITH ANY FREEZING POTENTIAL AT THIS
TIME.
RODRIGUEZ
&&
.LONG TERM...
214 AM CDT
FRIDAY THROUGH WEDNESDAY...
500MB TROUGH AXIS WILL BE PIVOTING EAST ACROSS THE REGION FRI
MORNING...WITH A WEAK LOW SKIRTING THE OHIO VALLEY AND ANOTHER LOW
WELL NORTH OVER JAMES BAY. THIS WILL PLACE THE FORECAST AREA IN A
WEAK DIFFLUENCE ZONE WITH DEPARTING LOW/MID LVL MOISTURE. THE
RESULT APPEARS TO BE A QUICK SURGE IN A 850MB THERMAL RIDGE OF 6
TO 9 DEG C AIR LIFTING NORTHEAST ACROSS THE CWFA. SFC TEMPS SHUD
REBOUND INTO THE MID/UPR 50S. THE LONGWAVE PATTERN
FLATTENS...ALLOWING FOR A SLIGHTLY MORE PROGRESSIVE FLOW HEADING
INTO THE WEEKEND. WITH THE AFOREMENTIONED LOW NEAR JAMES
BAY...THIS WILL SETUP A TRAILING FRONTAL BOUNDARY THAT WILL
STRETCH SOUTHWEST ACROSS THE UPPER MIDWEST LATE FRI. THIS FEATURE
WILL BECOME A FOCAL POINT SAT AFTN/EVE FOR A SHARPENING BAROCLINIC
ZONE.
GUIDANCE CONTINUES TO KEEP THE ENVIRONMENT RELATIVELY DRY SAT INTO
SAT NIGHT...HOWEVER THE FRONTAL BOUNDARY WILL BE SLIDING SOUTH
ACROSS THE FORECAST AREA SAT AFTN/EVE WITH MUCH COOLER AIR. CANADIAN
SFC RIDGE WILL PUSH SOUTHEAST INTO THE UPPER MIDWEST/NORTHERN GREAT
LAKES SAT AFTN/EVE. SIMULATNEOUSLY GUIDANCE HAS PROGGED A WEAK LOBE
OF VORTICITY TO EJECT FROM THE CENTRAL ROCKIES AND DEVELOP A SFC
WAVE SAT NGT. THIS FEATURE WILL INTERACT WITH THE FRONTAL BOUNDARY
EARLY SUN...WITH A STEADY FEED OF MOISTURE INTO THE MID-MISSOURI
VALLEY. THE PRECIP SHIELD SHUD EVENTUALLY OVERCOME THE DRY NEAR SFC
CONDS...AND ARRIVE OVER THE CWFA SUN EVE. SOUNDINGS WOULD SUGGEST
PRECIP FALLING AS LGT SNOW...HOWEVER ENOUGH WARMTH COULD PROVIDE A
RA/SN MIX AT THE ONSET BEFORE DYNAMICALLY COOLING TO ALL SNOW.
TEMPS SUN WILL LIKELY REMAIN IN THE LOW/MID 40S...HOWEVER COULD SEE
TEMPS A FEW DEGREES COOLER BY MID/LATE AFTN.
MONDAY THROUGH THURSDAY... ENSEMBLES CONTINUE THE THEME OF TROUGHING
ACROSS THE GREAT LAKES THRU EARLY NEXT WEEK...WITH THE HIGH
AMPLITUDE RIDGING RELAXING TOWARDS MID-WEEK AND TRANSITIONING INTO A
SLIGHTLY MORE FLAT FLOW. UNSEASONABLY COOL AIR FOR MON WITH HIGHS
MAINLY IN THE UPR 30S...THEN BEGINNING TO REBOUND TUE INTO THE MID
40S. SFC RIDGE PUSHES EAST MID-WEEK...WITH WHAT APPEARS TO BE A
QUICK WARM PUSH AGAIN WED. BY THE MIDDLE OF NEXT WEEK GUIDANCE HAS
YET ANOTHER SHORTWAVE ARRIVING...AND APPEARS SOME INSTABILITY COULD
ACCOMPANY IT.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIND SPEEDS AND DIRECTIONS THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
WINDS HAVE BEEN THE CHALLENGE TODAY...GOING A BIT EARLIER THAN
EXPECTED TO STRONGER SPEEDS AND A MORE EASTERLY DIRECTION THIS
MORNING...AND THEN VEERING SOUTHEASTERLY AGAIN BY EARLY
AFTERNOON WHILE INCREASING FURTHER. SPEEDS ARE EXPECTED TO RELAX
SOMEWHAT THIS AFTERNOON BUT THE DIRECTION MAY AGAIN TURN MORE
EASTERLY IF A LAKE BREEZE INFLUENCE DEVELOPS...SO GETTING BACK TO
A MORE FAVORABLE CONFIGURATION AT ORD MAY HAVE TO WAIT UNTIL LATER
THIS EVENING...PROBABLY AFTER THE PEAK RUSH.
ALSO MAINTAINED THE MENTION OF SHRA FOR LATER THIS EVENING BUT GIVEN
THE DRY AIR IN PLACE TODAY IT COULD BE HARD TO GET MORE THAN SOME
SPRINKLES OR BRIEF LIGHT RAIN SHOWERS.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM FOR WIND AND LOW FOR SHRA CHANCES BUT OTHERWISE HIGH.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
214 AM CDT
DEPARTING SURFACE RIDGE TO THE EAST WILL ALLOW WINDS TO BECOME
SOUTHEASTERLY THEN SOUTHWESTERLY BY FRI EVENING. AN AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ACROSS ONTARIO TO JAMES BAY
FRI...WITH A TRAILING FRONTAL BOUNDARY STRETCHED SOUTHWEST ACROSS
THE UPPER MIDWEST. HIGH PRESSURE WILL ALSO BE STRETCHED ACROSS THE
OHIO VALLEY AND INFLUENCE THE BULK OF LAKE MICHIGAN FRI INTO FRI
NGT. A WEAK LOW IS EXPECTED TO THEN DEVELOP FRI EVENING ALONG THE
SOUTHWEST PORTION OF THE LOW AND SLIDE EAST ACROSS CENTRAL LAKE
MICHIGAN EARLY SAT. THIS WILL HELP TO PUSH THE FRONTAL BOUNDARY
FURTHER SOUTH AND CLEAR THE LAKE BY SAT AFTN...WITH WINDS TURNING
NORTH/NORTHEAST BEHIND THE FRONT. THEN HIGH PRESSURE ACROSS
CENTRAL CANADA WILL SLIDE SOUTHEAST ACROSS THE UPPER MIDWEST
SUN...WITH A TIGHTENING GRADIENT ACROSS THE SOUTHERN THIRD OF THE
LAKE AND WINDS TURNING EAST AND SOUTHEAST ACROSS THE SOUTHERN
TIP. HIGH PRESSURE THEN SPREADS SLOWLY SOUTHEAST ACROSS THE LAKE
MON INTO TUE...WITH A MUCH LIGHTER PRESSURE GRADIENT.
BEACHLER
&&
.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
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1230 PM CDT Thu Mar 19 2015
.UPDATE...
ISSUED AT 954 AM CDT THU MAR 19 2015
Narrow west-east bands of echoes continue to appear on radar,
mostly near the I-70 corridor. Some periodic light rain has been
reported, but there were also some sleet reports as well near
Effingham. Some more widespread rain showers were occurring in
central and west central Missouri, and latest runs of the HRRR and
NAM show this increasing as it moves eastward this afternoon ahead
of a shortwave that will be moving out of the Dakotas. Have sent
some refinements of the rain chances in the grids/zones, focusing
the best chances from about mid afternoon through late evening. No
significant changes made to temperatures.
&&
.SHORT TERM...(Today)
ISSUED AT 327 AM CDT THU MAR 19 2015
Dissipating short-wave tracking into the Tennessee River Valley has
spread light rain as far north as south-central Illinois early this
morning, with 07Z/2am radar imagery showing precip just south of a
Jacksonville to Paris line. 00Z KILX upper air sounding featured
plenty of dry air below 700mb, which is effectively keeping the
precip from spreading any further north. Recent radar trends and
HRRR forecasts support this as well, showing the light rain staying
across the far southern KILX CWA through mid-morning. As the
initial wave ripples by to the south, a second northern-stream
wave currently evident on water vapor imagery over the western
Dakotas will approach from the northwest later in the day. All
models suggest this feature will draw moisture currently across
Missouri/southern Illinois back northward this afternoon. Given
initially dry low-level air mass and continued easterly flow, think
this will be a slow process. Have therefore slowed the northward
spread of precip, delaying it across much of the CWA until
afternoon. In fact, areas around Rantoul and Danville may stay dry
until closer to evening. Further west, have raised PoPs to likely
along/west of a Peoria to Mattoon line this afternoon. Due to
extensive cloud cover, light easterly winds, and eventually light
rain...have undercut the warm MAV guidance by several degrees. High
temperatures will range from the middle 40s far southwest around
Jacksonville to around 50 degrees along/east of I-57.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 327 AM CDT THU MAR 19 2015
Light rain will be ongoing across much of the area this evening, as
short-wave tracks into the southern Great Lakes. As this feature
moves further east, the rain will come to an end from west to east
overnight. Total rainfall through tonight will generally range from
one tenth to one quarter of an inch.
High pressure will build into the region on Friday, providing dry
and seasonably warm conditions with highs well into the 50s. Even
warmer weather is expected on Saturday, as southwesterly winds
increase in advance of an approaching cold front. Boundary will pass
through Saturday afternoon/evening, but before it does, high
temperatures will climb into the lower to middle 60S. Once front
exits, a chilly air mass will settle into the area for early next
week.
00Z Mar 19 models continue to show a clipper system approaching from
the northwest Sunday night into Monday, with minor timing
differences noted. Given presence of initially dry air mass beneath
surface high pressure on Sunday, think precip with this feature will
be delayed. As a result, will keep Sunday evening dry with chance
PoPs spreading across the western half of the CWA overnight. With
850mb temps in the 0 to -5C range and ample evaporational cooling
occurring, think precip type will be snow or a rain/snow mix. This
wintry precip will continue into Monday morning before surface temps
warm sufficiently to support all rain by midday. The clipper will
be weakening as it tracks southeastward across the area and with
temps quickly climbing above freezing Monday morning, am expecting
little or no snow accumulation.
Once this system passes, cool/dry weather will be on tap for Tuesday
before yet another wave and its associated cold front approach on
Wednesday. GFS/ECMWF are in good agreement concerning timing of
this system, with both models spreading rain into Illinois Tuesday
night into Wednesday. Will carry high chance PoPs accordingly,
with southerly flow ahead of the cold front pushing high temps
back into the upper 50s and lower 60s on Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1230 PM CDT THU MAR 19 2015
Main forecast issue will be with development of MVFR/IFR
conditions later this afternoon and evening. MVFR ceilings
spreading toward the IL/MO border with IFR conditions underneath
the rain further west in Missouri. Some moistening of the lower
levels of the atmosphere will need to take place as the
precipitation arrives in central Illinois over the next few hours,
so current thinking is that ceilings below 3,000 feet will start
moving into KPIA/KSPI after 22-23Z and encompassing the remaining
TAF sites this evening. Have introduced some IFR ceilings from
KSPI-KCMI overnight, becoming more widespread as the rain exits in
the 05-09Z time frame. Further north, have kept KPIA/KBMI as MVFR
overnight. Some clearing should begin Friday morning from the
northwest, but a passing upper trough will likely keep MVFR
ceilings in much of central Illinois through a good part of the
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT THU MAR 19 2015
.SHORT TERM...
325 AM CDT
TODAY AND TONIGHT...
MAIN FORECAST CHALLENGES ARE WITH PRECIP TRENDS THIS EVENING
THROUGH THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN THIRD OF
THE CWA WITH PRIMARILY RAIN EXPECTED...BUT WITH THE POSSIBILITY
FOR A BRIEF WINDOW OF A RAIN SNOW MIX.
QUIET CONDITIONS IN THE NEAR TERM AS HIGH PRESSURE SPANS THE
GREAT LAKES REGION. MID/HIGH CLOUDS CONTINUE TO SPREAD OVERHEAD
FROM BOTH THE SOUTHERN STREAM ENERGY AND APPROACHING MID LEVEL
TROUGH OVER THE NORTHERN PLAINS. CURRENT CLOUDY CONDITIONS WILL
REMAIN POSSIBLY BRIEFLY THINNING AT TIMES FOR A TIME THIS
MORNING...BUT WITH INCREASING CLOUDS EXPECTED ONCE AGAIN THROUGH
MIDDAY. DESPITE CLOUDS IN PLACE...HIGHS AROUND 50 ARE EXPECTED
TODAY WITH SLIGHTLY COOLER CONDITIONS IN THE LOW TO MID 40S NEAR
THE LAKE.
THE BULK OF THE PRECIP THIS MORNING REMAINS WELL SOUTH OF THE
AREA OVER THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY. GUIDANCE
CONTINUES TO SHOW THAT THIS PRECIP WILL BLOSSOM FURTHER NORTH
LATER THIS AFTERNOON AND EARLY EVENING. THIS WILL BE IN RESPONSE
TO PERSISTENT SHORT WAVE ENERGY...WAA...AND BETTER LARGE SCALE
SUPPORT WITH APPROACHING TROUGH FROM THE NORTHWEST. HOWEVER...IT
DOES APPEAR THAT THIS WILL BE FOCUSED MORE ALONG THE SOUTHERN
THIRD OF THE CWA WITH THE FAR SOUTHERN TIER HAVING THE BEST
CHANCE. DID INCLUDE LIKELY POPS IN THIS LOCATION WITH CHANCE TO
SLIGHT CHANCE POPS FURTHER NORTH...JUST NORTH OF THE I80 CORRIDOR.
PRECIP WILL LIKELY STAY ALONG AND SOUTH OF I80 BUT WITH GUIDANCE
STILL VARYING TO THE NORTHERN EXTENT OF THIS PRECIP
SHIELD...WANTED TO KEEP AT LEAST SLIGHT CHANCE POPS SLIGHTLY
FURTHER NORTH. TIMING APPEARS TO BE FROM EARLY EVENING TO LATE
EVENING WITH IT THEN EXITING AFTER THE MIDNIGHT TIME FRAME.
THERMAL PROFILES SUGGEST ALL RAIN OVER THE ENTIRE CWA BUT IT DOES
LOOK LIKE THERE COULD BE A PERIOD WHEN SOME LOCATIONS COULD
OBSERVE A BRIEF WINDOW OF A RAIN SNOW MIX. HOWEVER...NOT OVERLY
EXCITED WITH THIS POSSIBILITY AND HAVE LEFT OUT ANY MENTION OF
SNOW IN THE GRIDS. LOW TEMPS TONIGHT WILL BE IN THE MID TO UPPER
30S...AND AM NOT CONCERNED WITH ANY FREEZING POTENTIAL AT THIS
TIME.
RODRIGUEZ
&&
.LONG TERM...
214 AM CDT
FRIDAY THROUGH WEDNESDAY...
500MB TROUGH AXIS WILL BE PIVOTING EAST ACROSS THE REGION FRI
MORNING...WITH A WEAK LOW SKIRTING THE OHIO VALLEY AND ANOTHER LOW
WELL NORTH OVER JAMES BAY. THIS WILL PLACE THE FORECAST AREA IN A
WEAK DIFFLUENCE ZONE WITH DEPARTING LOW/MID LVL MOISTURE. THE
RESULT APPEARS TO BE A QUICK SURGE IN A 850MB THERMAL RIDGE OF 6
TO 9 DEG C AIR LIFTING NORTHEAST ACROSS THE CWFA. SFC TEMPS SHUD
REBOUND INTO THE MID/UPR 50S. THE LONGWAVE PATTERN
FLATTENS...ALLOWING FOR A SLIGHTLY MORE PROGRESSIVE FLOW HEADING
INTO THE WEEKEND. WITH THE AFOREMENTIONED LOW NEAR JAMES
BAY...THIS WILL SETUP A TRAILING FRONTAL BOUNDARY THAT WILL
STRETCH SOUTHWEST ACROSS THE UPPER MIDWEST LATE FRI. THIS FEATURE
WILL BECOME A FOCAL POINT SAT AFTN/EVE FOR A SHARPENING BAROCLINIC
ZONE.
GUIDANCE CONTINUES TO KEEP THE ENVIRONMENT RELATIVELY DRY SAT INTO
SAT NIGHT...HOWEVER THE FRONTAL BOUNDARY WILL BE SLIDING SOUTH
ACROSS THE FORECAST AREA SAT AFTN/EVE WITH MUCH COOLER AIR. CANADIAN
SFC RIDGE WILL PUSH SOUTHEAST INTO THE UPPER MIDWEST/NORTHERN GREAT
LAKES SAT AFTN/EVE. SIMULATNEOUSLY GUIDANCE HAS PROGGED A WEAK LOBE
OF VORTICITY TO EJECT FROM THE CENTRAL ROCKIES AND DEVELOP A SFC
WAVE SAT NGT. THIS FEATURE WILL INTERACT WITH THE FRONTAL BOUNDARY
EARLY SUN...WITH A STEADY FEED OF MOISTURE INTO THE MID-MISSOURI
VALLEY. THE PRECIP SHIELD SHUD EVENTUALLY OVERCOME THE DRY NEAR SFC
CONDS...AND ARRIVE OVER THE CWFA SUN EVE. SOUNDINGS WOULD SUGGEST
PRECIP FALLING AS LGT SNOW...HOWEVER ENOUGH WARMTH COULD PROVIDE A
RA/SN MIX AT THE ONSET BEFORE DYNAMICALLY COOLING TO ALL SNOW.
TEMPS SUN WILL LIKELY REMAIN IN THE LOW/MID 40S...HOWEVER COULD SEE
TEMPS A FEW DEGREES COOLER BY MID/LATE AFTN.
MONDAY THROUGH THURSDAY... ENSEMBLES CONTINUE THE THEME OF TROUGHING
ACROSS THE GREAT LAKES THRU EARLY NEXT WEEK...WITH THE HIGH
AMPLITUDE RIDGING RELAXING TOWARDS MID-WEEK AND TRANSITIONING INTO A
SLIGHTLY MORE FLAT FLOW. UNSEASONABLY COOL AIR FOR MON WITH HIGHS
MAINLY IN THE UPR 30S...THEN BEGINNING TO REBOUND TUE INTO THE MID
40S. SFC RIDGE PUSHES EAST MID-WEEK...WITH WHAT APPEARS TO BE A
QUICK WARM PUSH AGAIN WED. BY THE MIDDLE OF NEXT WEEK GUIDANCE HAS
YET ANOTHER SHORTWAVE ARRIVING...AND APPEARS SOME INSTABILITY COULD
ACCOMPANY IT.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* WINDS HAVE INCREASED AS PREVIOUSLY MENTIONED AND REMAIN JUST
SOUTH OF EASTERLY BUT ARE EXPECTED TO RELAX A BIT THIS
AFTERNOON.
LENNING
//DISCUSSION...UPDATED 12Z...
VFR CONDITIONS WILL CONTINUE THIS FORECAST PERIOD WITH A LOW
CHANCE OF RAIN LATER THIS EVENING. LATEST TRENDS WOULD SUGGEST
THE BULK OF THIS RAIN WILL STAY SOUTH OF THE TERMINALS...WITH THE
NORTHERN EDGE OF THIS PRECIP LIKELY NEARING ORD/MDW BUT WITH GYY
HAVING THE BEST CHANCE. LIGHT EAST SOUTHEAST WINDS THIS MORNING
ARE EXPECTED TO SLOWLY INCREASE LATER THIS MORNING...AS LAKE
INFLUENCE HELPS WINDS BECOME MORE EAST NORTHEAST BY MIDDAY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM FOR WIND...OTHERWISE HIGH. WINDS LIKELY STAYING BETWEEN
EAST AND SOUTHEAST AND IN THE TEENS...WITH GUSTS TO AROUND 20 IN
THE LATE MORNING AND EARLY AFTERNOON.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
214 AM CDT
DEPARTING SURFACE RIDGE TO THE EAST WILL ALLOW WINDS TO BECOME
SOUTHEASTERLY THEN SOUTHWESTERLY BY FRI EVENING. AN AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ACROSS ONTARIO TO JAMES BAY
FRI...WITH A TRAILING FRONTAL BOUNDARY STRETCHED SOUTHWEST ACROSS
THE UPPER MIDWEST. HIGH PRESSURE WILL ALSO BE STRETCHED ACROSS THE
OHIO VALLEY AND INFLUENCE THE BULK OF LAKE MICHIGAN FRI INTO FRI
NGT. A WEAK LOW IS EXPECTED TO THEN DEVELOP FRI EVENING ALONG THE
SOUTHWEST PORTION OF THE LOW AND SLIDE EAST ACROSS CENTRAL LAKE
MICHIGAN EARLY SAT. THIS WILL HELP TO PUSH THE FRONTAL BOUNDARY
FURTHER SOUTH AND CLEAR THE LAKE BY SAT AFTN...WITH WINDS TURNING
NORTH/NORTHEAST BEHIND THE FRONT. THEN HIGH PRESSURE ACROSS
CENTRAL CANADA WILL SLIDE SOUTHEAST ACROSS THE UPPER MIDWEST
SUN...WITH A TIGHTENING GRADIENT ACROSS THE SOUTHERN THIRD OF THE
LAKE AND WINDS TURNING EAST AND SOUTHEAST ACROSS THE SOUTHERN
TIP. HIGH PRESSURE THEN SPREADS SLOWLY SOUTHEAST ACROSS THE LAKE
MON INTO TUE...WITH A MUCH LIGHTER PRESSURE GRADIENT.
BEACHLER
&&
.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
NATIONAL WEATHER SERVICE LINCOLN IL
956 AM CDT Thu Mar 19 2015
.UPDATE...
ISSUED AT 954 AM CDT THU MAR 19 2015
Narrow west-east bands of echoes continue to appear on radar,
mostly near the I-70 corridor. Some periodic light rain has been
reported, but there were also some sleet reports as well near
Effingham. Some more widespread rain showers were occurring in
central and west central Missouri, and latest runs of the HRRR and
NAM show this increasing as it moves eastward this afternoon ahead
of a shortwave that will be moving out of the Dakotas. Have sent
some refinements of the rain chances in the grids/zones, focusing
the best chances from about mid afternoon through late evening. No
significant changes made to temperatures.
&&
.SHORT TERM...(Today)
ISSUED AT 327 AM CDT THU MAR 19 2015
Dissipating short-wave tracking into the Tennessee River Valley has
spread light rain as far north as south-central Illinois early this
morning, with 07Z/2am radar imagery showing precip just south of a
Jacksonville to Paris line. 00Z KILX upper air sounding featured
plenty of dry air below 700mb, which is effectively keeping the
precip from spreading any further north. Recent radar trends and
HRRR forecasts support this as well, showing the light rain staying
across the far southern KILX CWA through mid-morning. As the
initial wave ripples by to the south, a second northern-stream
wave currently evident on water vapor imagery over the western
Dakotas will approach from the northwest later in the day. All
models suggest this feature will draw moisture currently across
Missouri/southern Illinois back northward this afternoon. Given
initially dry low-level air mass and continued easterly flow, think
this will be a slow process. Have therefore slowed the northward
spread of precip, delaying it across much of the CWA until
afternoon. In fact, areas around Rantoul and Danville may stay dry
until closer to evening. Further west, have raised PoPs to likely
along/west of a Peoria to Mattoon line this afternoon. Due to
extensive cloud cover, light easterly winds, and eventually light
rain...have undercut the warm MAV guidance by several degrees. High
temperatures will range from the middle 40s far southwest around
Jacksonville to around 50 degrees along/east of I-57.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 327 AM CDT THU MAR 19 2015
Light rain will be ongoing across much of the area this evening, as
short-wave tracks into the southern Great Lakes. As this feature
moves further east, the rain will come to an end from west to east
overnight. Total rainfall through tonight will generally range from
one tenth to one quarter of an inch.
High pressure will build into the region on Friday, providing dry
and seasonably warm conditions with highs well into the 50s. Even
warmer weather is expected on Saturday, as southwesterly winds
increase in advance of an approaching cold front. Boundary will pass
through Saturday afternoon/evening, but before it does, high
temperatures will climb into the lower to middle 60S. Once front
exits, a chilly air mass will settle into the area for early next
week.
00Z Mar 19 models continue to show a clipper system approaching from
the northwest Sunday night into Monday, with minor timing
differences noted. Given presence of initially dry air mass beneath
surface high pressure on Sunday, think precip with this feature will
be delayed. As a result, will keep Sunday evening dry with chance
PoPs spreading across the western half of the CWA overnight. With
850mb temps in the 0 to -5C range and ample evaporational cooling
occurring, think precip type will be snow or a rain/snow mix. This
wintry precip will continue into Monday morning before surface temps
warm sufficiently to support all rain by midday. The clipper will
be weakening as it tracks southeastward across the area and with
temps quickly climbing above freezing Monday morning, am expecting
little or no snow accumulation.
Once this system passes, cool/dry weather will be on tap for Tuesday
before yet another wave and its associated cold front approach on
Wednesday. GFS/ECMWF are in good agreement concerning timing of
this system, with both models spreading rain into Illinois Tuesday
night into Wednesday. Will carry high chance PoPs accordingly,
with southerly flow ahead of the cold front pushing high temps
back into the upper 50s and lower 60s on Wednesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 607 AM CDT THU MAR 19 2015
VFR conditions will prevail at all TAF sites this morning and into
early afternoon. Then as clouds lower during the afternoon, will
include VCSH to catch any light rain showers than might occur. As
the rain does begin later this afternoon and into early this
evening, cig heights are expected to drop to 3 kft or less. As the
rain gets steadier, the vis will drop to around 5SM at all sites.
The pcpn will continue during the evening, but then end from
northwest to eastward at midnight or later. Should end at PIA
first and then last at CMI. Will keep fog in the forecast, based
on light winds and some low level moisture. Winds will be east to
southeasterly at 12kts or less during the day, but then become
light and variable through the rest of the period tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
609 AM CDT THU MAR 19 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 232 AM CDT THU MAR 19 2015
THE MOST SIGNIFICANT FORECAST CHALLENGES FOR THE SHORT TERM ARE 1)
VISIBILITY RESTRICTION IN FOG THIS MORNING; 2) EVOLUTION OF LIGHT
RAIN DURING THE DAY AND TIMING THE CESSATION OF RAIN; 3)
TEMPERATURES TODAY; AND 4) PATCHY FOG THURSDAY NIGHT. INTERACTION
BETWEEN FLOW AROUND AN UPPER LEVEL CYCLONE CENTERED OVER THE
NORTHERN GULF OF CALIFORINA AND UPPER LEVEL TROUGHS RIPPLING THROUGH
THE NORTHERN BRANCH OF THE WESTERLIES ACROSS THE NORTHERN UNITED
STATES IS CONTRIBUTING TO METEOROLOGICAL UNCERTAINTY IN THE CENTRAL
PLAINS. A SURFACE CYCLONE WAS CENTERED IN NORTHEAST NEW MEXICO EARLY
THIS MORNING WITH A DEVELOPING WARM FRONT EXTENDING FROM THE CYCLONE
INTO CENTRAL TEXAS. AN UPPER LEVEL TROUGH WAS EVIDENT ON SATELLITE
IMAGERY FROM SOUTH CENTRAL COLORADO TO EASTERN NEW MEXICO, AND
ANOTHER STRONGER UPPER LEVEL TROUGH WAS APPROACHING WESTERN MEXICO.
THE TROUGH APPROACHING WESTERN MEXICO WILL PROPAGATE NORTHEAST INTO
WESTERN TEXAS THIS AFTERNOON, AND THE SURFACE CYCLONE WILL MOVE
ALONG THE BAROCLINIC ZONE NEAR THE RED RIVER INTO NORTHERN TEXAS
THIS EVENING. THE UPPER LEVEL TROUGH FROM SOUTHERN COLORADO INTO
EASTERN NEW MEXICO WILL MOVE INTO WESTERN KANSAS THIS MORNING AND
WILL WEAKEN IN THE CONFLUENT UPPER LEVEL FLOW OVER THE CENTRAL
PLAINS.
MOIST UPSLOPE FLOW HAS FAVORED DEVELOPMENT OF WIDESPREAD STRATUS IN
CENTRAL AND EASTERN KANSAS, AND THE AREA OF STRATUS WILL CONTINUE TO
PROPAGATE WEST THROUGH THE EARLY MORNING HOURS. THE BEST OPPORTUNITY
FOR FOG WITH VISIBILITIES BELOW A MILE WILL BE NEAR THE WEST EDGE OF
THE MOISTURE FIELD FROM NORTH CENTRAL INTO WEST CENTRAL KANSAS. WITH
THE WEAKNESS OF THE LOW LEVEL FLOW AND EXTENSIVE MID AND HIGH LEVEL
CLOUDINESS TO INTERFERE WITH RADIATIONAL COOLING, SURFACE COOLING
WEST OF THE RICHER MOISTURE FIELD LIKELY WILL NOT BE SUFFICIENT TO
ALLOW THE GROUND TO COOL ENOUGH TO SUPPORT EVOLUTION OF DENSE FOG AS
THE HIGHER DEWPOINTS GRADUALLY ADVECT WEST. WIDESPREAD VISIBILITIES
OF ONE TO TWO MILES SEEM LIKELY.
SCATTERED LIGHT SHOWERS HAVE BEEN PERSISTENT IN ADVANCE OF A MID
LEVEL DEFORMATION ZONE FROM EASTERN INTO SOUTH CENTRAL KANSAS DURING
THE NIGHT AND LIKELY WILL CONTINUE INTO THE MORNING HOURS. AS THE
UPPER LEVEL TROUGH MOVES FROM COLORADO AND NEW MEXICO INTO WESTERN
KANSAS THIS MORNING, A WEAK MID LEVEL CIRCULATION IS LIKELY TO
DEVELOP IN SOUTHWEST KANSAS ALONG A SHARP H7 BAROCLINIC ZONE AND
GRADUALLY TO WEAKEN AS IT MOVES EAST DURING THE DAY. A JET STREAK
EAST OF THE GULF OF CALIFORNIA UPPER LEVEL LOW WILL INCREASE IN
STRENGTH TODAY, AND UPPER LEVEL DIVERGENCE IN THE LEFT EXIT REGION
OF THE JET STREAK WILL ENHANCE UPWARD VERTICAL MOTION IN SOUTHWEST
KANSAS. THE COMBINATION OF UPPER LEVEL DIVERGENCE AND WEAK
ISENTROPIC LIFT OVER THE MID LEVEL BAROCLINIC ZONE WILL SUPPORT
DEVELOPMENT OF WIDESPREAD LIGHT RAIN THIS MORNING. AS THE JET STREAK
PROPAGATES EAST THIS AFTERNOON, UPWARD VERTICAL MOTION WILL
DECREASE, AND ISENTROPIC DOWNGLIDE WILL EVOLVE IN THE MID LEVELS OF
THE ATMOSPHERE. RAIN WILL END FROM NORTH TO SOUTH LATE HIS AFTERNOON
AND EARLY THIS EVENING AS SUBSIDENCE BEGINS AND DRY AIR IN THE LOW
LEVELS INVADES WESTERN KANSAS.
TEMPERATURES TODAY WILL BE SLOW TO RISE WITH EXTENSIVE CLOUD COVER
AND PRECIPITATION. THE WARMEST READINGS LIKELY WILL BE IN NORTHERN
KANSAS, WHERE CLOUDINESS WILL ERODE ENOUGH TO ALLOW AT LEAST SOME
SOLAR RADIATION TO REACH THE SURFACE. MOST HIGHS WILL BE IN THE 40S.
WINDS WILL BECOME LIGHT AND VARIABLE THIS EVENING WITH A WEAK
SURFACE HIGH PRESSURE RIDGE IN KANSAS AND WILL BECOME LIGHT WEST
AFTER MIDNIGHT. MODEL SOUNDINGS ARE VERY DRY ABOVE THE SURFACE
TONIGHT AND ARE NOT SUPPORTIVE OF FOG FORMATION; HOWEVER, THE MOIST
BOUNDARY LAYER SHOULD PRODUCE SOME REALLY HEAVY DEW AND PATCHY
RADIATION FOG IN LOW LYING AREAS IS POSSIBLE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 244 AM CDT THU MAR 19 2015
A COLD FRONT WILL MOVE SOUTH ACROSS THE NORTHERN PLAINS ON FRIDAY
AS AN UPPER LEVEL TROUGH EXITS CENTRAL CANADA AND MOVES INTO THE
WESTERN GREAT LAKES REGION. AHEAD OF THIS COLD FRONT 850MB
TEMPERATURES ARE FORECAST BY THE NAM AND GFS AT 00Z SATURDAY TO
RANGE FROM +9C IN SOUTH CENTRAL KANSAS TO NEAR +13C ACROSS
NORTHWEST KANSAS. BASED ON THESE TEMPERATURES LATE FRIDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK WITH HIGHS RANGING FROM THE
MID 60S TO LOWER 70S.
THE WEAK COLD FRONT WILL MOVE INTO NORTHERN KANSAS LATE FRIDAY
NIGHT WHERE IT WILL BRIEFLY BECOME STATIONARY ON SATURDAY. A
TROUGH OF LOW PRESSURE WILL DEEPEN NEAR THE COLORADO BORDER DURING
THE DAY AS A WEAK UPPER LEVEL DISTURBANCE APPROACHES THE AREA FROM
THE WEST. ACROSS NORTH CENTRAL KANSAS THE 850MB TEMPERATURE TREND
FROM 00Z SATURDAY TO 00Z SUNDAY INDICATED AT 1 TO 2 WARMUP.
FURTHER WEST/SOUTHWEST THE 850MB TEMPERATURES WARM 4 TO 6C OVER
THE SAME TIME FRAME. GIVEN THESE TEMPERATURE TRENDS THE PREVIOUS
FORECAST STILL LOOKS ON TRACK WITH TEMPERATURES BEING WARMER ON
SATURDAY COMPARED TO FRIDAY WITH THE LARGER WARMUP BEING ACROSS
SOUTHWEST KANSAS.
ON SATURDAY NIGHT A WEAK UPPER LEVEL DISTURBANCE WILL BEGIN TO
CROSS THE CENTRAL HIGH PLAINS WITH 700-500MB LAPSE RATES BETWEEN
00Z SUNDAY TO 06Z SUNDAY RANGING FROM 7 TO AROUND 7.5 C/KM. GFS
DOES ATTEMPT TO GENERATE SOME PRECIPITATION AHEAD OF THIS WEEKEND
SYSTEM BUT IT ALSO HAS BETTER MOISTURE RETURN OCCURRING OVER
WESTERN KANSAS. ECMWF KEEPS THE BETTER MOISTURE FURTHER SOUTH
CLOSER TO THE WEAKENING UPPER LEVEL TROUGH THAT WILL BE CROSSING
NORTH TEXAS. AT THIS TIME GIVEN SOME CONCERN ON MOISTURE OVER
WESTERN KANSAS SATURDAY NIGHT WILL ONLY INCREASE CLOUD COVER AT
THIS TIME AHEAD OF THIS WEAK UPPER LEVEL DISTURBANCE.
ON SUNDAY THIS MOISTURE RETURN OVER WESTERN KANSAS WILL GET
SHUNTED EAST AS THE SURFACE TROUGH OF LOW PRESSURE MOVES INTO
CENTRAL KANSAS. ANOTHER WEAK UPPER DISTURBANCE WILL THEN CROSS THE
CENTRAL HIGH PLAINS SUNDAY NIGHT INTO EARLY MONDAY AS THE COLD
FRONT FINALLY MOVE ACROSS WESTERN KANSAS. THIS NEXT FEATURE
APPEARS TO HAVE SLIGHTLY BETTER UPPER LEVEL DYNAMICS BASED ON THE
LOCATION OF THE 70-80KT 250MB JET STREAK EARLY MONDAY MORNING.
MOISTURE HOWEVER MAY BE MORE QUESTIONABLE ACROSS FAR WESTERN
KANSAS NORTH OF THE COLD FRONT. MID LEVEL INSTABILITY STILL
PRESENT BASED ON THE 700MB TO 500MB LAPSE RATES SO GIVEN BETTER
JET DYNAMICS LATE SUNDAY NIGHT INTO MONDAY WILL RETAIN A MENTION
OF SHOWERS AND ISOLATED THUNDERSTORMS AS THIS NEXT WEAK FEATURE
CROSSES WESTERN KANSAS.
AN UPPER LEVEL RIDGE AXIS AXIS WILL CROSS THE ROCKIES MONDAY AND
TUESDAY AS AN UPPER LEVEL TROUGH EXITS THE EASTERN PACIFIC AND
BEGINS TO CROSS THE PACIFIC NORTHWEST. AS THIS UPPER RIDGE AXIS
CROSSES THE ROCKIES A WESTERLY DOWNSLOPE FLOW WILL IMPROVE ACROSS
WESTERN KANSAS. BASED ON IMPROVING DOWNSLOPE FLOW AND RIDGING
ALOFT EARLY NEXT WEEK WILL STAY CLOSE TO THE LATEST
CREXTENDFCST_INIT WITH TEMPERATURES CLIMBING BACK AT LEAST INTO
THE LOW TO MID 70S BY TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 607 AM CDT THU MAR 19 2015
LIGHT RAIN WILL INCREASE IN AREAL COVERAGE ACROSS SOUTHWEST
KANSAS THIS MORNING AND THEN CONTINUE THROUGH THE LATE AFTERNOON.
MODEL SOUNDINGS, RAP, AND HRRR ALL SUGGEST THAT THE LIFR/IFR CLOUD
BASES WILL BEGIN TO GRADUALLY IMPROVE LATE MORNING AND CONTINUE
THROUGH THE LATE AFTERNOON. AT THIS TIME CEILINGS ARE EXPECTED TO
IMPROVE INTO THE LOW VFR CATEGORY BETWEEN 20Z THURSDAY AND 00Z
FRIDAY. AT DDC AND GCK MVFR VISIBILITIES FROM FOG AND LIGHT RAIN
WILL BE LIKELY UNTIL MID AFTERNOON. AT HYS MVFR VISIBILITIES ARE
EXPECTED TO IMPROVE BY 18Z. WINDS WILL BE MAINLY NORTHEAST AT 10
KNOTS OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 34 69 40 / 90 40 0 0
GCK 46 32 68 38 / 90 30 0 0
EHA 46 36 64 40 / 90 40 0 0
LBL 46 34 66 39 / 90 50 0 0
HYS 53 32 71 38 / 40 0 0 0
P28 48 36 70 43 / 90 40 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUTHI
LONG TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1107 PM EDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 1105 PM EDT FRI MAR 20 2015
HOURLY GRIDS WERE UPDATED BASED ON RECENT RADAR AND OBSERVATION
TRENDS. AREAS OF DRIZZLE CONTINUE ACROSS THE RADAR PER OBS AND
RADAR IMAGERY GENERALLY SOUTH OF INTERSTATE 64 AND EAST OF
INTERSTATE 75. THIS SHOULD GRADUALLY DIMINISH AS THE MOISTURE
BECOMES SHALLOWER. PATCHY FOG IS STILL ANTICIPATED AND MAY BE
DENSE AT TIMES ON SOME RIDGES. CLOUDS SHOULD NOT SCATTER OUT UNTIL
AROUND DAYBREAK...EXCEPT PERHAPS IN THE FAR NORTHWEST.
UPDATE ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 810 PM EDT FRI MAR 20 2015
LOW CLOUDS...AND EVEN PATCHY DRIZZLE WILL KEEP IFR AND MVFR
CONDITIONS GOING ACROSS EASTERN KENTUCKY THROUGH THE EVENING.
ANY DRIZZLE SHOULD END BY 6Z...BUT THE LOW CLOUDS IN THE IFR
AND MVFR RANGE SHOULD PERSIST THROUGH THE NIGHT. THESE CLOUDS
THEN LOOK TO SCATTER OUT GENERALLY BETWEEN 12Z AND 18Z...WITH VFR
CONDITIONS DEVELOPING AND REMAINING IN PLACE THROUGH THE END OF
THE PERIOD. WINDS WILL GENERALLY BE AROUND 5 KT OR LESS THROUGH
THE PERIOD OUT OF THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...GREIF/JP
AREA FORECAST DISCUSSION
NWS PADUCAH KY
940 PM CDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 940 PM CDT FRI MAR 20 2015
UPDATED FORECAST TO INCREASE SKY COVER THROUGH THE REMAINDER OF THE
NIGHT. AS LOW CLOUDS CONTINUE TO CLEAR...HIGH CLOUDS ARE ON THE
INCREASE. MODEL FORECAST OF 300 MB DEWPOINT DEPRESSION SUGGESTS THIS
HIGH CLOUD COVER WILL LIKELY STICK AROUND THROUGH MUCH OF THE NIGHT.
REMAINDER OF FORECAST IS UNCHANGED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
LOW LEVEL TRAJECTORIES NOT FAVORABLE FOR RAPID CLEAR OUT...BUT
SLOWLY OVER TIME...HIGH PRESSURE WORKS IN AND ACROSS THE TENNESSEE
VALLEY AND OVERALL SUBSIDENCE/DRYING THROUGH THE COLUMN SHOULD WIN
OUT...CERTAINLY...BY TMRW. THIS WILL RESULT IN A NICE WARMUP WITH
TEMPS CLIMBING THRU THE 60S AND FLIRTING WITH/REACHING TOWARD 70
ESP ACROSS OUR SOUTH/WEST.
A MORE OR LESS ZONAL FLOW THEN RIDES OUT THE REMAINDER OF THE
SHORT TERM AND CARRIES THE FORECAST THRU THE WEEKEND. ENERGY IN
THE FLOW PATTERN TO OUR NORTH AND SOUTH MEANS MORE CLOUDS SUNDAY
THAN SATURDAY...AND AS A RESULT...TEMPS MAY NOT CLIMB AS HIGH BUT
WILL STILL BE RELATIVELY PLEASANT IN THE 60S.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
HIGH CONFIDENCE THROUGH MID WEEK....DECREASING TO LOW CONFIDENCE
AFTER THURSDAY.
THE MODELS ARE IN GOOD AGREEMENT WITH NEXT SYSTEM TO MOVE THROUGH
MID WEEK...BUT AFTER THAT THEY DIVERGE A GREAT DEAL. THEY BOTH KEEP
US UNDER A SLOW MOVING UPPER TROUGH BUT DIFFER IN SPOKES OF ENERGY
MOVING THROUGH THE TROF AND AVAILABLE MOISTURE. THE GFS CONTINUES TO
SHOW NUMEROUS SPOKES OF ENERGY PRODUCING LIGHT RAIN AFTER THE MAIN
COLD FRONT PASSAGE IN CONTRAST TO SEVERAL RUNS OF THE ECMWF WHICH
KEEPS US DRY AFTER THURSDAY. MAY HAVE SOME SLIGHT CHANCES IN FOR THE
POSSIBILITY THE GFS VERIFIES BUT WILL WAIT AND SEE WHAT THE EXTENDED
INIT YIELDS AND TAKE IT FROM THERE. I INTRODUCED THUNDER YESTERDAY
AND NOW THINK IT WILL BE SURFACE BASED WITH LI`S AT THE SURFACE
YIELDING -1 TO -4. ALSO K INDEX 30 AND ABOVE WITH SHOWALTER ZERO
TO -4. WILL KEEP TRW- OVER THE ENTIRE AREA THROUGH 00Z THURSDAY
AND THEN TAPER IT OFF TO ALONG AND SOUTHEAST OF THE OHIO RIVER
0-06Z THU. PLAN ON TAKING THUNDER COMPLETELY OUT AFTER 06Z
THURSDAY. THE THUNDER WILL BE POSSIBLE IN THE WARM SECTOR AFTER
THE WARM FRONT HAS LIFTED NORTH AND AHEAD OF THE APPROACHING COLD
FRONT FROM THE NORTHWEST.
SLIGHTLY ABOVE NORMAL TEMPERATURES FOR MOST OF THE WORK WEEK WILL
FALL BELOW NORMAL IN THE COLD FRONTS WAKE AT THE END OF THE WORK
WEEK.
&&
.AVIATION...
ISSUED AT 411 PM CDT FRI MAR 20 2015
SIGNIFICANT CHANGES MADE TO THE TAFS. DECK OF CLOUDS WITH MVFR
BASES WILL MOVE OUT. SATELLITE SHOWS CLEARING IMMINENT AT KCGI AND
WILL SOON FOLLOW AT KPAH. SHOULD HAPPEN BY 01-02Z AT KEVV AND
KOWB. THE RAP IS NOT DEPICTING THE PLACEMENT CORRECTLY...TOO FAR
SOUTH...SO WILL STRICTLY FOLLOW SATELLITE. MODELS DO NOT LINGER
THE LOW LEVEL MOISTURE AROUND OVERNIGHT. JUST HIGH CLOUDS AT
TIMES. WILL TAKE ANOTHER LOOK AT THE PROSPECT FOR SOME LIGHT FOG
GIVEN LIGHT WINDS AND RESIDUAL LOW LEVEL MOISTURE. THE LATEST MOS
DOES HINT AT IT FOR LATE TONIGHT...EARLY SATURDAY MORNING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
830 PM EDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 810 PM EDT FRI MAR 20 2015
LOW CLOUDS...AND EVEN PATCHY DRIZZLE WILL KEEP IFR AND MVFR
CONDITIONS GOING ACROSS EASTERN KENTUCKY THROUGH THE EVENING.
ANY DRIZZLE SHOULD END BY 6Z...BUT THE LOW CLOUDS IN THE IFR
AND MVFR RANGE SHOULD PERSIST THROUGH THE NIGHT. THESE CLOUDS
THEN LOOK TO SCATTER OUT GENERALLY BETWEEN 12Z AND 18Z...WITH VFR
CONDITIONS DEVELOPING AND REMAINING IN PLACE THROUGH THE END OF
THE PERIOD. WINDS WILL GENERALLY BE AROUND 5 KT OR LESS THROUGH
THE PERIOD OUT OF THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...GREIF/JP
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1254 PM CDT THU MAR 19 2015
.AVIATION...
SOME LINGERING CIGS BELOW 030 WILL KEEP MVFR CONDITIONS AROUND
SOME AIRPORTS EARLY THIS AFTERNOON...HOWEVER MOST LOCATIONS SHOULD
SEE THE LOWER CLOUD DECKS SCATTER OUT. VISIBLE SATELLITE IMAGERY
INDICATED MODERATE TO TOWERING CUMULUS CLOUDS...AND RADAR
INDICATED A FEW SHRA WERE DEVELOPING. THESE SHRA ARE EXPECTED TO
REMAIN ISOLATED IN MOST LOCATIONS...BUT A FEW AIRPORTS COULD HAVE
SOME BRIEF IMPACTS WITH CIGS AND LOWERED VSBYS. THE MAIN CONCERN
IS FOR LOW STRATUS AND FOG LATE TONIGHT INTO FRIDAY MORNING WHICH
APPEARS LIKELY...AND HAVE ADDED LIFR CONDITIONS TO THE 18Z TAFS.
22/TD
&&
.PREV DISCUSSION... /ISSUED 1014 AM CDT THU MAR 19 2015/
UPDATE...
BASED ON RADAR TRENDS AND THE 12Z SOUNDING HAVE LOWERED POPS
ACROSS THE AREA TO SLIGHT CHANCE...AND COMPLETELY REMOVED THE
MENTION OF RAIN FROM THE FORECAST FOR TONIGHT AND TOMORROW
MORNING. HAVE ALSO INCREASED THE FOG COVERAGE FOR TONIGHT...AS
LIGHT BOUNDARY LAYER WINDS AND A HIGH DEWPOINT AIRMASS CREATE
FAVORABLE CONDITIONS FOR FOG TO FORM. SIMILAR CONDITIONS ARE
EXPECTED FOR TOMORROW NIGHT. TEMPERATURES ARE ON TRACK AT MOST
LOCATIONS. HOWEVER...CONDITIONS ARE WARMING FASTER THAN
ANTICIPATED ON THE MISSISSIPPI GULF COAST. EXPECT TO SEE A
SEABREEZE FORM BY EARLY AFTERNOON...WHICH SHOULD KEEP TEMPERATURES
MORE STEADY ALONG THE COAST IN THE AFTERNOON HOURS. 32
PREV DISCUSSION... /ISSUED 415 AM CDT THU MAR 19 2015/
SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 20 20 40 40
BTR 81 62 82 64 / 20 20 30 40
ASD 80 63 81 65 / 20 10 30 30
MSY 80 63 80 65 / 20 10 20 20
GPT 77 63 77 64 / 20 10 30 20
PQL 80 62 79 64 / 20 10 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1014 AM CDT THU MAR 19 2015
.UPDATE...
BASED ON RADAR TRENDS AND THE 12Z SOUNDING HAVE LOWERED POPS
ACROSS THE AREA TO SLIGHT CHANCE...AND COMPLETELY REMOVED THE
MENTION OF RAIN FROM THE FORECAST FOR TONIGHT AND TOMORROW
MORNING. HAVE ALSO INCREASED THE FOG COVERAGE FOR TONIGHT...AS
LIGHT BOUNDARY LAYER WINDS AND A HIGH DEWPOINT AIRMASS CREATE
FAVORABLE CONDITIONS FOR FOG TO FORM. SIMILAR CONDITIONS ARE
EXPECTED FOR TOMORROW NIGHT. TEMPERATURES ARE ON TRACK AT MOST
LOCATIONS. HOWEVER...CONDITIONS ARE WARMING FASTER THAN
ANTICIPATED ON THE MISSISSIPPI GULF COAST. EXPECT TO SEE A
SEABREEZE FORM BY EARLY AFTERNOON...WHICH SHOULD KEEP TEMPERATURES
MORE STEADY ALONG THE COAST IN THE AFTERNOON HOURS. 32
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT THU MAR 19 2015/
SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 20 20 40 40
BTR 81 62 82 64 / 20 20 30 40
ASD 80 63 81 65 / 20 10 30 30
MSY 80 63 80 65 / 20 10 20 20
GPT 77 63 77 64 / 20 10 30 20
PQL 80 62 79 64 / 20 10 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
415 AM CDT THU MAR 19 2015
.SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
.LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
&&
.AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
&&
.MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
&&
.DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 30 20 40 40
BTR 81 62 82 64 / 30 20 30 40
ASD 80 63 81 65 / 30 20 30 30
MSY 80 63 80 65 / 20 20 20 20
GPT 77 63 77 64 / 30 20 30 20
PQL 80 62 79 64 / 30 20 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
958 AM EDT THU MAR 19 2015
.SYNOPSIS...
STRONG LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES
TODAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT AND
CREST OVER THE REGION FRIDAY. LOW PRESSURE SYSTEMS FROM THE MID
ATLANTIC STATES AND CENTRAL CANADA WILL APPROACH LATE FRIDAY NIGHT
AND TRACK SOUTH AND NORTH OF THE REGION BY SAT NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
945 AM UPDATE: LATEST IR ENHANCED SATELLITE IMAGERY SHOWED CLOUDS
DROPPING SOUTHWARD ACROSS NORTHERN MAINE DOWN INTO EAST-CENTRAL
AREAS. STREAMLINE TRAJECTORIES AT 12Z SHOWED A NICE CONVERGENCE
AXIS IN PLACE ACROSS THE NORTH AND NORTHWEST AREAS W/A SFC TROF IN
PLACE. 12Z UA SHOWED A TROF DROPPING SE FROM SOUTHERN CANADA INTO
NORTHERN MAINE W/NW FLOW SETTING UP AGAIN. STREAMER ACTION CAN BE
SEEN ON THE VISIBLE SATELLITE IMAGERY AS WELL OFF THE OPEN ST.
LAWRENCE. THIS ACTION WILL ALLOW FOR SOME LIGHT SNOW/FLURRIES INTO
THE AFTERNOON. THIS IS WELL SUPPORTED BY THE RAP SOUNDINGS SHOWING
MOISTURE TRAPPED BENEATH 6K FT. SB CAPE CLIMBS TO 30-40 JOULES
W/SOME STEEPENING OF THE LAPSE RATES, ESPECIALLY BELOW 3 KM.
THEREFORE, DECIDED TO ADD POPS UP TO 30% ACROSS THE NORTHERN AND
EASTERN AREAS FOR SOME LIGHT SNOW/FLURRIES.
AS MENTIONED BY THE MIDNIGHT CREW, THE STEEPER LAPSE RATES WILL
LEAD TO GUSTY WINDS INTO THE AFTERNOON W/POTENTIAL OF 40 MPH OVER
HIGHER TERRAIN. KEPT PATCHY BLOWING SNOW IN PLACE. HRLY TEMPS
WERE ADJUSTED TO MATCH THE LATEST OBS, WHICH SHOWS A WARMER TREND.
AFTERNOON MAXES MAY NEED TO BE BOOSTED ESPECIALLY DOWNEAST TO THE
COAST W/MORE SUN. WILL TAKE A LOOK AT THINGS AFTER 11 AM. R
A MDTLY STRONG SFC PRES GRAD AND WINDS IN THE 925 TO 850 MB LAYER
ABOUT 25 KT XPCTD TO CONT OVR THE REGION INTO AFTN...THE POTENTIAL
OF BRISK GUSTY WINDS TO 35 MPH AND EVEN 40+ MPH OVR HIER TRRN
EXISTS LATER THIS MORN INTO MID AFTN WHEN SFC-1000M LAPSE RATES
BECOME STEEP. WIND GUSTS OF 35+ MPH WILL STILL BE CAPABLE OF
PRODUCING PATCHY BLSN OVR OPEN TRRN AREAS...BUT ALL IN ALL
CONDITIONS WILL STILL BE AN IMPROVEMENT OVR YSTDY WHICH FEATURED
MORE WIDESPREAD BLSN. HI TEMPS THIS AFTN WILL CONT VERY COLD...BUT
NOT QUITE AS COLD AS YSTDY AFTN.
WITH BOTH THE SFC PRES GRAD AND WINDS ALF SLACKENING AFT SUNSET...
WINDS SHOULD DECREASE TO A LGT BREEZE OVR ERN PTNS OF THE FA...
AND EVEN DECOUPLE OVR BROAD WRN VLYS LATE TNGT AS THE AXIS OF THE
SFC HI APCHS THIS PTN OF THE REGION BY ERLY FRI MORN. THE
POTENTIAL OF SHALLOW SFC-BASE INVSN OVR THE BROAD WRN VLYS SHOULD
ALLOW FOR LOW TEMPS TO FALL BLO ZERO OVR THIS AREA...WITH SINGLE
DIGITS OVR THE REST OF THE N AND CNTRL AND ARND 10 ABV FOR
DOWNEAST AREAS BY ERLY FRI MORN.
FRI WILL BEGIN SUNNY...THEN CLDNSS FROM SFC LOWS AND ASSOCIATED
S/WVS FROM THE MID ATLC STATES AND CNTRL CAN BEGIN TO ARRIVE FRI
AFTN...SPCLY OVR WRN PTNS OF THE FA. WITH MUCH LIGHTER WINDS HI
TEMPS SHOULD CONT TO RECOVER ON FRI...REACHING THE LOWER TO MID
30S ACROSS ALL XCPT HIGHEST TRRN LCTNS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
PRECIPITATION CHANCES INCREASE FOR THE END OF THE WEEK AS AN
UPPER TROUGH APPROACHES FROM THE NORTHWEST. THE LATEST RUN OF THE
ECMWF HAS COME INTO LINE WITH THE REST OF THE GUIDANCE WITH THE
HANDLING OF THIS SYSTEM. MODEL CONSENSUS DEVELOPS A NORTHERN
STREAM SURFACE LOW WHICH WOULD TRACK ACROSS SOUTHERN
QUEBEC/NORTHERN MAINE, BRINGING ITS ATTENDANT COLD FRONT TO OUR
WESTERN AREAS BY SATURDAY EVENING. THIS SOLUTION ALSO DEVELOPS A
SOUTHERN LOW BUT KEEPS IT WELL SOUTH OF NOVA SCOTIA. THIS PATTERN
WOULD MEAN A MIX OF LIGHT RAIN AND SNOW FOR OUR FORECAST AREA
DURING THE DAY SATURDAY. HAVE GONE WITH A BLEND THAT LEANED
HEAVILY ON THE GFS AND ALSO INCLUDED THE PREVIOUS FORECAST TO
MAINTAIN SOME CONSISTENCY. THE MAIN CHANGE WAS TO INCREASE QPF A
BIT OVER NORTHERN AND WESTERN MAINE WHILE LOWERING IT DOWNEAST AND
OVER THE WATERS. TEMPERATURES WILL BE IN THE LOWER TO MID 30S ON
SATURDAY, SO EXPECT THAT DOWNEAST WILL CHANGE OVER TO RAIN FOR A
TIME DURING THE AFTERNOON. ELSEWHERE, RAIN WILL AT LEAST MIX WITH
SNOW, EXCEPT IN THE HIGHER TERRAIN IN THE NORTH WOODS. SNOW
ACCUMULATION WILL BE AROUND AN INCH AT MOST, THOUGH THE HIGHER
TERRAIN MAY SEE AROUND 2 INCHES BY SATURDAY EVENING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE AFOREMENTIONED COLD FRONT WILL CROSS THE STATE FROM WEST TO
EAST SATURDAY NIGHT. THIS WILL ALLOW PRECIPITATION TO TAPER OFF TO
SHOWERS WHILE CHANGING OVER TO ALL SNOW. A MUCH COLDER AIRMASS
WILL FOLLOW, WITH BRISK NORTHWEST WINDS AND WELL BELOW NORMAL
TEMPERATURES FOR SUNDAY THROUGH MONDAY. LINGERING SNOW SHOWERS
WILL BE POSSIBLE OVER FAR NORTHERN AREAS EARLY NEXT WEEK AS WELL.
WE`LL START TO SEE SOME IMPROVEMENT ON TUESDAY AS HIGH PRESSURE
CRESTS OVER THE REGION. THE HIGH WILL MOVE OFFSHORE ON WEDNESDAY,
PLACING NEW ENGLAND UNDER SOUTHWEST FLOW AND ALLOWING TEMPERATURES
TO FINALLY GET CLOSE TO NORMAL.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR XPCTD THRU FRI...WITH PERHAPS BRIEF INTERVALS OF
SC MVFR CLGS THIS MORN OVR NRN MOST TAF SITES...SPCLY KFVE.
SHORT TERM: VFR CONDITIONS FRIDAY NIGHT AND EARLY SATURDAY WILL
GIVE WAY TO MVFR/LOCAL IFR BY SATURDAY AFTERNOON AS LIGHT RAIN AND
SNOW CROSS THE REGION. THE NORTHERN TERMINALS, ESPECIALLY KFVE,
HAVE THE BEST CHANCES OF REMAINING ALL SNOW DURING THE DAY
SATURDAY. MVFR TO LINGER THROUGH AT LEAST 06Z SUNDAY, WITH IFR
POSSIBLE AT KFVE DUE TO SNOW SHOWERS COMING OFF THE SAINT
LAWRENCE. CONDITIONS WILL IMPROVE DURING THE DAY SUNDAY WITH ALL
SITES TO BE VFR BY 00Z MONDAY.
&&
.MARINE...
NEAR TERM: WILL CONT WITH THE GALE WRNG OVR OUR WATERS WITH LLVL
COLD ADVCN WNW WINDS...DUE TO EXPIRE AT NOON...AT WHICH POINT AN
INTERIM SCA WILL LIKELY BE NEEDED FOR THE REMAINDER OF THE AFTN
INTO ERLY EVE...SPCLY OVR THE OUTER MZS WATERS. THE FZGSPY ADV FOR
MDT FZSPY WOULD ALSO EXPIRE OVR OUR WATERS AT NOON...FOLLOWED BY
A PD OF LGT FZSPY ROUGHLY CORRESPONDING WITH SCA CONDITIONS.
AFTWRDS...WE ANTICIPATE NO HDLNS LATER TNGT CONTG THRU FRI.
INITIALLY ERLY THIS MORN...OBSVD WV HTS ARE RUNNING ABOUT 1 TO 2
FT ABV FCST WW3 WV GUIDANCE...THEN WE SLOWLY MERGE TO WW3 GUIDANCE
LATE TNGT INTO FRI.
SHORT TERM: GALE HEADLINES WILL LIKELY BE NEEDED ACROSS THE
WATERS FOR EARLY NEXT WEEK. A STRONG COLD FRONT WILL CROSS THE
WATERS LATE SATURDAY, WITH MUCH COLDER AIR SPREADING IN ITS WAKE.
THIS WILL RESULT IN GUSTY NORTHWEST WINDS OF 20 TO 25 KT, WITH
GUSTS OF 35-40 KT. SEAS WILL BE 5 TO 8 FEET. SMALL CRAFT
CONDITIONS WILL BE MET BY MIDNIGHT SUNDAY MORNING, WITH GALES TO
PREVAIL THROUGH THE DAY SUNDAY INTO SUNDAY EVENING. THERE WILL BE
SOME IMPROVEMENT MONDAY, THOUGH WINDS WILL LIKELY STAY ABOVE SMALL
CRAFT CRITERIA UNTIL MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...FREEZING SPRAY ADVISORY UNTIL NOON EDT TODAY FOR ANZ050>052.
GALE WARNING UNTIL NOON EDT TODAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT/VJN
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...HEWITT/VJN/HASTINGS
MARINE...HEWITT/VJN/HASTINGS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
622 AM EDT THU MAR 19 2015
.SYNOPSIS...
STRONG LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES
TODAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT AND
CREST OVER THE REGION FRIDAY. LOW PRESSURE SYSTEMS FROM THE MID
ATLANTIC STATES AND CENTRAL CANADA WILL APPROACH LATE FRIDAY NIGHT
AND TRACK SOUTH AND NORTH OF THE REGION BY SAT NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
610 AM UPDATE: LATEST RADAR REF IMAGERY AND SFC OBS FROM KCAR
STILL INDICATE SCT FLURRIES INTERSECTING FAR NE AROOSTOOK COUNTY
ATTMS ERLY THIS MORN...WITH LATEST HRRR MODEL OUTPUT SUGGESTING
THAT ALL SN SHWR ACTIVITY EXITING OUT FA VIA NB BY 8 AM EDT.
OTHERWISE...FCST LOWS WERE UPDATED BY SUBTRACTING TWO DEG F FROM
6 AM EDT OBSVD TEMP GRID AND POSTING THE RESULT AT 7 AM. THIS
RESULTED IN LOWS NOT AS PREVIOUSLY COLD OVR ERN ME ERLY THIS MORN
DUE TO PERSISTENT CLD CVR. FCST HRLY TEMPS WERE THEN UPDATED INTO
THE AFTN TO UNCHGD FCST HI TEMPS POSTED AT 4-5 PM EDT. WINDS...
WHICH HAVE DROPPED OFF SOME ERLY THIS MORN...WILL INCREASE
SOMEWHAT LATER THIS MORN AS SFC TEMPS RISE...RESULTING IN
STEEPENING SFC-500M LAPSE RATES AND BETTER MIXING OF STRONGER
WIND ALF TO THE SFC AS WIND GUSTS.
ORGNL DISC: SAT IMAGERY STILL SHOWS CLDNSS ACROSS NRN AND ERN
PTNS OF THE FA FROM THE SLOWLY RETREATING SFC/UPPER LOW OVR THE
ERN CAN MARITIMES...BUT BELIEVE THIS CLD DECK IS RELATIVELY THIN.
MOST OF THIS CLDNSS WILL MOVE E OUT OF THE REGION THIS AFTN AS THE
LOW CONTS E INTO THE OPEN N ATLC. WITH A MDTLY STRONG SFC PRES
GRAD AND WINDS IN THE 925 TO 850 MB LAYER ABOUT 25 KT XPCTD TO
CONT OVR THE REGION INTO AFTN...THE POTENTIAL OF BRISK GUSTY WINDS
TO 35 MPH AND EVEN 40+ MPH OVR HIER TRRN EXISTS LATER THIS MORN
INTO MID AFTN WHEN SFC-1000M LAPSE RATES BECOME STEEP. WIND GUSTS
OF 35+ MPH WILL STILL BE CAPABLE OF PRODUCING PATCHY BLSN OVR OPEN
TRRN AREAS...BUT ALL IN ALL CONDITIONS WILL STILL BE AN
IMPROVEMENT OVR YSTDY WHICH FEATURED MORE WIDESPREAD BLSN. HI
TEMPS THIS AFTN WILL CONT VERY COLD...BUT NOT QUITE AS COLD AS
YSTDY AFTN.
WITH BOTH THE SFC PRES GRAD AND WINDS ALF SLACKENING AFT SUNSET...
WINDS SHOULD DECREASE TO A LGT BREEZE OVR ERN PTNS OF THE FA...
AND EVEN DECOUPLE OVR BROAD WRN VLYS LATE TNGT AS THE AXIS OF THE
SFC HI APCHS THIS PTN OF THE REGION BY ERLY FRI MORN. THE
POTENTIAL OF SHALLOW SFC-BASE INVSN OVR THE BROAD WRN VLYS SHOULD
ALLOW FOR LOW TEMPS TO FALL BLO ZERO OVR THIS AREA...WITH SINGLE
DIGITS OVR THE REST OF THE N AND CNTRL AND ARND 10 ABV FOR
DOWNEAST AREAS BY ERLY FRI MORN.
FRI WILL BEGIN SUNNY...THEN CLDNSS FROM SFC LOWS AND ASSOCIATED
S/WVS FROM THE MID ATLC STATES AND CNTRL CAN BEGIN TO ARRIVE FRI
AFTN...SPCLY OVR WRN PTNS OF THE FA. WITH MUCH LIGHTER WINDS HI
TEMPS SHOULD CONT TO RECOVER ON FRI...REACHING THE LOWER TO MID
30S ACROSS ALL XCPT HIGHEST TRRN LCTNS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
PRECIPITATION CHANCES INCREASE FOR THE END OF THE WEEK AS AN
UPPER TROUGH APPROACHES FROM THE NORTHWEST. THE LATEST RUN OF THE
ECMWF HAS COME INTO LINE WITH THE REST OF THE GUIDANCE WITH THE
HANDLING OF THIS SYSTEM. MODEL CONSENSUS DEVELOPS A NORTHERN
STREAM SURFACE LOW WHICH WOULD TRACK ACROSS SOUTHERN
QUEBEC/NORTHERN MAINE, BRINGING ITS ATTENDANT COLD FRONT TO OUR
WESTERN AREAS BY SATURDAY EVENING. THIS SOLUTION ALSO DEVELOPS A
SOUTHERN LOW BUT KEEPS IT WELL SOUTH OF NOVA SCOTIA. THIS PATTERN
WOULD MEAN A MIX OF LIGHT RAIN AND SNOW FOR OUR FORECAST AREA
DURING THE DAY SATURDAY. HAVE GONE WITH A BLEND THAT LEANED
HEAVILY ON THE GFS AND ALSO INCLUDED THE PREVIOUS FORECAST TO
MAINTAIN SOME CONSISTENCY. THE MAIN CHANGE WAS TO INCREASE QPF A
BIT OVER NORTHERN AND WESTERN MAINE WHILE LOWERING IT DOWNEAST AND
OVER THE WATERS. TEMPERATURES WILL BE IN THE LOWER TO MID 30S ON
SATURDAY, SO EXPECT THAT DOWNEAST WILL CHANGE OVER TO RAIN FOR A
TIME DURING THE AFTERNOON. ELSEWHERE, RAIN WILL AT LEAST MIX WITH
SNOW, EXCEPT IN THE HIGHER TERRAIN IN THE NORTH WOODS. SNOW
ACCUMULATION WILL BE AROUND AN INCH AT MOST, THOUGH THE HIGHER
TERRAIN MAY SEE AROUND 2 INCHES BY SATURDAY EVENING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE AFOREMENTIONED COLD FRONT WILL CROSS THE STATE FROM WEST TO
EAST SATURDAY NIGHT. THIS WILL ALLOW PRECIPITATION TO TAPER OFF TO
SHOWERS WHILE CHANGING OVER TO ALL SNOW. A MUCH COLDER AIRMASS
WILL FOLLOW, WITH BRISK NORTHWEST WINDS AND WELL BELOW NORMAL
TEMPERATURES FOR SUNDAY THROUGH MONDAY. LINGERING SNOW SHOWERS
WILL BE POSSIBLE OVER FAR NORTHERN AREAS EARLY NEXT WEEK AS WELL.
WE`LL START TO SEE SOME IMPROVEMENT ON TUESDAY AS HIGH PRESSURE
CRESTS OVER THE REGION. THE HIGH WILL MOVE OFFSHORE ON WEDNESDAY,
PLACING NEW ENGLAND UNDER SOUTHWEST FLOW AND ALLOWING TEMPERATURES
TO FINALLY GET CLOSE TO NORMAL.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR XPCTD THRU FRI...WITH PERHAPS BRIEF INTERVALS OF
SC MVFR CLGS THIS MORN OVR NRN MOST TAF SITES...SPCLY KFVE.
SHORT TERM: VFR CONDITIONS FRIDAY NIGHT AND EARLY SATURDAY WILL
GIVE WAY TO MVFR/LOCAL IFR BY SATURDAY AFTERNOON AS LIGHT RAIN AND
SNOW CROSS THE REGION. THE NORTHERN TERMINALS, ESPECIALLY KFVE,
HAVE THE BEST CHANCES OF REMAINING ALL SNOW DURING THE DAY
SATURDAY. MVFR TO LINGER THROUGH AT LEAST 06Z SUNDAY, WITH IFR
POSSIBLE AT KFVE DUE TO SNOW SHOWERS COMING OFF THE SAINT
LAWRENCE. CONDITIONS WILL IMPROVE DURING THE DAY SUNDAY WITH ALL
SITES TO BE VFR BY 00Z MONDAY.
&&
.MARINE...
NEAR TERM: WILL CONT WITH THE GALE WRNG OVR OUR WATERS WITH LLVL
COLD ADVCN WNW WINDS...DUE TO EXPIRE AT NOON...AT WHICH POINT AN
INTERIM SCA WILL LIKELY BE NEEDED FOR THE REMAINDER OF THE AFTN
INTO ERLY EVE...SPCLY OVR THE OUTER MZS WATERS. THE FZGSPY ADV FOR
MDT FZSPY WOULD ALSO EXPIRE OVR OUR WATERS AT NOON...FOLLOWED BY
A PD OF LGT FZSPY ROUGHLY CORRESPONDING WITH SCA CONDITIONS.
AFTWRDS...WE ANTICIPATE NO HDLNS LATER TNGT CONTG THRU FRI.
INITIALLY ERLY THIS MORN...OBSVD WV HTS ARE RUNNING ABOUT 1 TO 2
FT ABV FCST WW3 WV GUIDANCE...THEN WE SLOWLY MERGE TO WW3 GUIDANCE
LATE TNGT INTO FRI.
SHORT TERM: GALE HEADLINES WILL LIKELY BE NEEDED ACROSS THE
WATERS FOR EARLY NEXT WEEK. A STRONG COLD FRONT WILL CROSS THE
WATERS LATE SATURDAY, WITH MUCH COLDER AIR SPREADING IN ITS WAKE.
THIS WILL RESULT IN GUSTY NORTHWEST WINDS OF 20 TO 25 KT, WITH
GUSTS OF 35-40 KT. SEAS WILL BE 5 TO 8 FEET. SMALL CRAFT
CONDITIONS WILL BE MET BY MIDNIGHT SUNDAY MORNING, WITH GALES TO
PREVAIL THROUGH THE DAY SUNDAY INTO SUNDAY EVENING. THERE WILL BE
SOME IMPROVEMENT MONDAY, THOUGH WINDS WILL LIKELY STAY ABOVE SMALL
CRAFT CRITERIA UNTIL MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...FREEZING SPRAY ADVISORY UNTIL NOON EDT TODAY FOR ANZ050>052.
GALE WARNING UNTIL NOON EDT TODAY FOR ANZ050>052.
&&
$$
NEAR TERM...VJN
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...VJN/HASTINGS
MARINE...VJN/HASTINGS
AREA FORECAST DISCUSSION
NWS DULUTH MN
401 AM CDT THU MAR 19 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 401 AM CDT THU MAR 19 2015
MAIN FORECAST CHALLENGES THIS MORNING ARE RAIN/SNOW CHANCES
THROUGH THIS AFTERNOON AND AGAIN ON FRIDAY AFTERNOON.
WARM AIR ADVECTION AND WEAK MID-LEVEL FRONTOGENESIS SUPPORTED A
BAND OF LIGHT SNOW FROM EASTERN NORTH DAKOTA SOUTHEAST TO WESTERN
WISCONSIN EARLY THIS MORNING. VERY DRY AIR IN THE MID/LOW- LEVELS
AS INDICATED BY 00Z MPX/INL SOUNDINGS AND MID-LEVEL CEILINGS WAS
EVAPORATING PRECIPITATION FROM CENTRAL MINNESOTA TO WESTERN
WISCONSIN. HAVE TRENDED FORECAST TOWARD NAM/SREF SOLUTION THROUGH
LATE AFTERNOON. EXPECT AREA FROM BRAINERD TO WALKER TO SATURATE
WITH A BRIEF PERIOD OF LIGHT SNOW BEFORE BAND MOVES OUT. SNOW
WILL CHANGE OVER TO RAIN BY NOON AS IT MOVES INTO FAR NORTH-
CENTRAL AND NORTHEAST MINNESOTA. EXPECT LESS THAN THREE-TENTHS OF
AN INCH OF SNOW ACCUMULATION... MAINLY ON GRASSY SURFACES.
TEMPERATURES WILL TREND SLIGHTLY WARMER WITH HIGHS IN THE UPPER
30S NORTHEAST AND THE LOW 50S SOUTHWEST.
PRECIPITATION WINDS DOWN TONIGHT IN NORTHEAST MINNESOTA. FORECAST
DRY FOR THE REMAINDER OF THE NIGHT AS WEAK SURFACE RIDGE SLIDES
THROUGH THE STATE. WITH WEAK WARM ADVECTION THROUGH TODAY...THINK
OVERNIGHT LOWS TONIGHT WILL TREND SLIGHTLY WARMER AS WELL. LOOK
FOR MIN TEMPS IN THE UPPER 20S NORTH TO THE LOW 30S SOUTH.
NEXT CLIPPER SYSTEM WILL MOVE INTO THE AREA ON FRIDAY BRINGING AN
INCREASE IN CLOUD COVER AND A BAND OF LIGHT RAIN...CHANGING OVER
TO SNOW ALONG THE NORTHERN EDGE DURING THE LATE AFTERNOON HOURS.
PREFER A CONSENSUS BLEND WEIGHTED TOWARD THE NAM/SREF FOR TIMING
AND POPS. RAIN TOTALS OF AROUND FIVE ONE-HUNDREDTHS SEEM
REASONABLE...WITH SOME SPOTS POSSIBLY RECEIVING A TENTH OF AN
INCH. TEMPS WILL TREND WARMER ACROSS THE SOUTH ONCE AGAIN WITH
STRONG WARM ADVECTION AHEAD OF THE CLIPPER. CLOUDS ACCOMPANYING
THE APPROACHING CLIPPER WILL LIMIT INSOLATION AND HEATING ACROSS
THE NORTH. HIGHS WILL REACH THE UPPER 30S NORTH...AND THE MIDDLE
50S SOUTHEAST.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 401 AM CDT THU MAR 19 2015
HIGH PRESSURE WILL MOVE INTO THE NORTHLAND AND UPPER MIDWEST OVER
THE WEEKEND AND HELP KEEP THE NORTHLAND DRY THROUGH EARLY NEXT
WEEK. TEMPERATURES WILL BE ABOUT 10 DEGREES BELOW NORMAL ON
SATURDAY...BUT WILL BUILD BACK TO NORMAL BY MONDAY.
THERE ARE SIGNS THAT A SIGNIFICANT STORM SYSTEM COULD DEVELOP IN
THE HIGH PLAINS AND MOVE THROUGH THE MINNESOTA AND WISCONSIN
DURING THE MIDDLE OF NEXT WEEK. THE GFS AND ECMWF ARE BOTH
INDICATING THIS SYSTEM. THE STORM IS TOO FAR OUT IN TIME TO
GATHER MUCH DETAILS...SO FORECASTED A MIXTURE OF RAIN AND SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1225 AM CDT WED MAR 18 2015
DRY AIR COVERED MUCH OF THE NORTHLAND LATE THIS EVENING AS SEEN
ON FORECAST SOUNDINGS AND EARLIER 00Z KMPX/KINL SOUNDINGS.
SURFACE DEWPOINTS HAVE BEEN INCREASING THOUGH. AREA RADARS
CONTINUE TO SHOW RETURNS FROM NORTHWEST NORTH DAKOTA SOUTHEAST
INTO WESTERN WISCONSIN. MUCH OF THESE RETURNS WERE NOT PRODUCING
PRECIP AT THE SURFACE...BUT THERE ARE SOME AREAS OF LIGHT SNOW OR
RAIN OCCURRING WEST OF THE NORTHLAND. WE DO NOT EXPECT MUCH
PRECIP ACROSS THE NORTHLAND TONIGHT...AS THE FGEN CONTINUES TO
WEAKEN. A SHORTWAVE OVER FAR WESTERN NORTH DAKOTA LATE THIS
EVENING WILL MOVE EAST ACROSS THE NORTHLAND ON THURSDAY. THERE
WILL BE A CHANCE FOR A LIGHT MIX ON THURSDAY WHICH SHOULD BECOME
MAINLY RAIN AS THE BOUNDARY LAYER WARMS. OVERALL...VFR CONDITIONS
WILL PREVAIL THROUGH THE PERIOD. THERE WILL BE 3 TO 4 HOUR PERIOD
WHERE MVFR CEILINGS WILL BE POSSIBLE. AT THIS TIME...WE CONFINED
THE MENTION TO KINL AND KHIB. THE RAP IS LESS BULLISH ON THESE
CEILINGS COMPARED TO THE NAM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 49 33 49 17 / 10 10 60 30
INL 46 29 38 6 / 40 10 10 10
BRD 52 31 52 20 / 10 10 40 20
HYR 48 33 54 19 / 0 10 50 50
ASX 49 34 52 19 / 10 0 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...HUYCK
LONG TERM...GROCHOCINSKI
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1225 AM CDT THU MAR 19 2015
.UPDATE...
ISSUED AT 1225 AM CDT WED MAR 18 2015
UPDATED FOR THE NEW 06Z AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 933 PM CDT WED MAR 18 2015
FORECAST REMAINS ON TRACK AND FEW CHANGES WERE NEEDED IN THE SHORT
TERM. FGEN BAND OF MAINLY SNOW SOUTH AND WEST OF THE NORTHLNAD CONTINUED
TO MAKE VERY SLOW PROGRESS NORTH THIS EVENING. FORECAST SOUNDINGS
AND EVENING KMPX/KINL SOUNDINGS CONTINUE TO INDICATE SOME VERY DRY
AIR IN PLACE ACROSS THE NORTHLAND. THIS FGEN IS EXPECTED TO WEAKEN
OVERNIGHT SO WE EXPECT LITTLE IN THE WAY OF PRECIP. WE WILL
CONTINUE A SMALL MENTION OF SNOW OVER PORTIONS OF NORTHERN
MINNESOTA LATE. THE 00Z NAM IS IN GOOD AGREEMENT WITH OUR CURRENT
FORECAST. WE MADE SOME MINOR ADJUSTMENTS TO TEMPS TONIGHT TO
ACCOUNT FOR CURRENT TRENDS.
AN UPPER WAVE WILL MOVE IN THURSDAY MORNING BRINGING A CHANCE FOR
MORE LIGHT PRECIP. ANY PRECIP WOULD START AS A MIX OR MAINLY
SNOW...THEN SWITCH OVER TO LIGHT RAIN.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 412 PM CDT WED MAR 18 2015
WIDESPREAD CIRROSTRATUS WILL CONTINUE TO STREAM ACROSS THE DULUTH
CWA TONIGHT..AND WILL THICKEN WITH TIME FROM SOUTH TO NORTH IN
ADVANCE OF A WEAK SHORT WAVE APPROACHING FROM THE DAKOTAS. SURFACE
WINDS WILL BECOME LIGHT SOUTH TO SOUTHEAST TONIGHT AS SURFACE HIGH
PRESSURE MOVES OFF TO THE EAST. TEMPS TONIGHT WILL LIKELY NOT DROP
TOO FAR/FAST WITH THE INCREASINGLY THICK CLOUD COVER. HOWEVER..
TEMPS ACROSS FAR NORTHERN MINNESOTA AND ESPECIALLY THE INTERIOR
ARROWHEAD WHERE CLOUDS WILL BE THINNER AND WINDS NEAR CALM..MAY
DROP A BIT MORE THEN WE HAVE FORECASTED.
WEAK ASCENT WILL LIKELY RESULT IN SCATTERED RAIN AND SNOW SHOWERS
ON THURSDAY. PTYPE WILL BE DEPENDENT ON BOUNDARY LAYER TEMPS..WITH
SNOW SHOWERS MORE LIKELY IN THE MORNING AND AGAIN IN THE
EVENING..WITH A CHANGE OVER TO MOSTLY RAIN SHOWERS DURING THE DAY
AS TEMPS WARM INTO THE MID 30S TO LOWER 40S. VERY DRY AIR IN THE
LOWEST LEVELS MAY ALSO RESULT IN A LOT OF THE PRECIP EVAPORATING
BEFORE REACHING THE GROUND. BEST CHANCES FOR A COUPLE TENTHS OF AN
INCH OF SNOW WILL BE ACROSS FAR NORTHERN MINNESOTA WHERE DEEPER
SATURATION WILL PERSIST FOR A LONGER PERIOD OF TIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 412 PM CDT WED MAR 18 2015
A COLD FRONT AND ASSOCIATED UPPER TROUGH WILL BE MOVING EWD
THROUGH NRN MN AND NRN WI THURSDAY NIGHT AND FRIDAY MORNING...WITH
LIGHT RAIN AND/OR SNOW SPREADING THROUGH THE REGION. A BRIEF BREAK
IN THE PRECIP WILL BE SEEN LATE FRI MORNING/EARLY AFTERNOON BEFORE
A POST FRONTAL TROUGH DROPS IN FROM THE NORTH AND PHASES WITH AN
SECONDARY SFC WAVE AND EMBEDDED MID-LEVEL TROUGH FROM THE
NORTHWEST. THIS SYSTEM ON FRIDAY WILL PRODUCE ANOTHER ROUND OF
MAINLY RAIN DURING THE DAY ALONG AND SOUTH OF THE HIGHWAY 2
CORRIDOR...AND A RAIN/SNOW MIX TO THE NORTH. RAINFALL AMOUNTS WILL
BE GENERALLY LIGHT...LESS THAN A QUARTER OF AN INCH WITH TRACE
SNOWFALL POSSIBLE. HIGH PRESSURE BUILDS IN FROM THE NORTH FOR THE
WEEKEND WITH A SLIGHT SHIFT IN THE RIDGE AXIS TO THE EAST BY
MONDAY AS THE NEXT SYSTEM MOVES FROM THE NRN/CENTRAL PLAINS INTO
THE MID MS RIVER VALLEY AND BRUSHES THE NORTHLAND WITH LOW-END
POPS IN THE BRAINERD AREA. THE NEXT SIGNIFICANT SYSTEM MOVES ON
TUESDAY WITH RAIN AND SNOW POSSIBLE.
MILD TEMPERATURES EXPECTED FRIDAY WITH HIGHS IN THE 40S AND LOWER
50S. HOWEVER THE FIRST PUSH OF COLD AIR ARRIVES FRIDAY NIGHT WITH
TEMPERATURES FALLING INTO THE SINGLE DIGITS TO LOWER 20S. THE COLD
AIR PERSISTS ON SATURDAY WITH HIGHS ONLY REACHING INTO THE 20S AND
LOWER/MID 30S. A SLIGHT WARMING TREND BEGINS SUNDAY INTO EARLY NEXT
WEEK WITH HIGHS EVENTUALLY INTO THE 40S...AND LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1225 AM CDT WED MAR 18 2015
DRY AIR COVERED MUCH OF THE NORTHLAND LATE THIS EVENING AS SEEN
ON FORECAST SOUNDINGS AND EARLIER 00Z KMPX/KINL SOUNDINGS.
SURFACE DEWPOINTS HAVE BEEN INCREASING THOUGH. AREA RADARS
CONTINUE TO SHOW RETURNS FROM NORTHWEST NORTH DAKOTA SOUTHEAST
INTO WESTERN WISCONSIN. MUCH OF THESE RETURNS WERE NOT PRODUCING
PRECIP AT THE SURFACE...BUT THERE ARE SOME AREAS OF LIGHT SNOW OR
RAIN OCCURRING WEST OF THE NORTHLAND. WE DO NOT EXPECT MUCH
PRECIP ACROSS THE NORTHLAND TONIGHT...AS THE FGEN CONTINUES TO
WEAKEN. A SHORTWAVE OVER FAR WESTERN NORTH DAKOTA LATE THIS
EVENING WILL MOVE EAST ACROSS THE NORTHLAND ON THURSDAY. THERE
WILL BE A CHANCE FOR A LIGHT MIX ON THURSDAY WHICH SHOULD BECOME
MAINLY RAIN AS THE BOUNDARY LAYER WARMS. OVERALL...VFR CONDITIONS
WILL PREVAIL THROUGH THE PERIOD. THERE WILL BE 3 TO 4 HOUR PERIOD
WHERE MVFR CEILINGS WILL BE POSSIBLE. AT THIS TIME...WE CONFINED
THE MENTION TO KINL AND KHIB. THE RAP IS LESS BULLISH ON THESE
CEILINGS COMPARED TO THE NAM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 45 33 48 / 10 20 30 50
INL 20 44 29 37 / 10 20 10 20
BRD 31 50 31 50 / 10 20 20 50
HYR 27 48 33 52 / 10 20 20 40
ASX 23 46 34 51 / 10 20 20 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
715 PM CDT Fri Mar 20 2015
.UPDATE:
Issued at 715 PM CDT Fri Mar 20 2015
Cirrus clouds are much thicker than originally anticipated based
on ground obs and visible satellite before the sun went down. Have
boosted sky cover for this evening for most of the area with the
trend expected to be for the thicker cloud cover to sag south a
bit overnight. SW surface winds also won`t allow much of a temp
drop either and so edged min temps up a deg or two as well for
many areas. Only in the far northern CWA around UIN will the
forecast be relatively unaffected.
TES
&&
.SHORT TERM: (Through Tonight)
Issued at 250 PM CDT Fri Mar 20 2015
Focus tonight will be temps.
Clouds continue to struggle to dissipate this afternoon. It appears
the RAP is handling these clouds the best for now. Nrn edge of the
clouds shud continue slowly moving ewd. Further S, believe clouds
will continue to dissipate and move newd. A section of the nrn
clouds from near KCOU to KUIN will likely be the last to dissipate
or advect out of the area. Across the srn portions of the CWA, CI
has already begun to move into the area and will continue to do so
overnight. However, it is a little uncertain how thick these clouds
will be.
Have trended twd the cooler guidance tonight partially because of
anticipating the clearing. However, going forecast may not be cold
enuf since temps struggled today.
Tilly
.LONG TERM: (Saturday through Next Friday)
Issued at 250 PM CDT Fri Mar 20 2015
A cdfnt shud have arrived across the nrn third of the CWA by 12z
Sat. This fnt will continue to push swd thru the day. While this may
be a cold fnt, with nearly full insolation expected, tomorrow shud
actually be warmer than today. Mdls also push the thermal ridge
across the region on Sat. The fnt begins to lift nwd on Sun as a sfc
low and associated s/w approach the region. While not high chances,
this system will bring a chance for RA across nrn portions of the
CWA Sun night and across much of the area on Mon, more probable
during the afternoon with heating.
As the trof deepens across the Plains and the LLJ increases with
what shud be an open Gulf, precip chances increase quickly Mon night
and Tues, with TS becoming more probable as well. Going forecast
PoPs may be too low attm, but have not gone higher for now due to
lack of persistence among mdl guidance. Given the amount of shear
available with the system on Tues, there is a very narrow window
where severe weather potential exists. However, given a number of
questions regarding timing with this event, will hold off mention in
products now other than that it remains to be a system to watch.
Behind the cdfnt late Wed and a secondary cdfnt on Thurs, the
potential for a very cold rain or possibly even light snow event
exists. Have kept as RA for now, but again, will be a system to
monitor.
Tilly
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 653 PM CDT Fri Mar 20 2015
Residual stratus/stratocu continues to slowly erode in a band that
originates from near Pike Counties in IL/MO to the NE into cntrl
and e cntrl IL. Meanwhile...thick cirrus continues to stream ENE
across the region from the sthrn Plains. There is the chance for
some MFVR fog around sunrise due to the recent damp conditions and
cloud cover hanging round for most of the day. Given that the
cirrus is thicker than originally thought...the threat for fog may
be less than previously thought...except at KUIN. Skies should be
clearer there than the rest of the TAF sites. Also...clouds didn`t
clear out til sunset and VSBYs remained MVFR most of the day. A
weak cold front pushes thru the terminals Sat mrng backing the
wind from SW to NE from mrng to aftn...but with speeds aob
10kts...impacts should be minimal.
Specifics for KSTL:
VFR fcst with the exception of the chance for some MVFR fog towards
12Z. Although this chance appears to be less then originally
thought with the thicker than expected cirrus overhead tonight.
Weak bndry pushes through tomorrow mrng switching the wind from SW
to E from mrng to evng though with speed expected aob 10 kts
impacts should be minimal.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
706 PM CDT Fri Mar 20 2015
.SHORT TERM: (Through Tonight)
Issued at 250 PM CDT Fri Mar 20 2015
Focus tonight will be temps.
Clouds continue to struggle to dissipate this afternoon. It appears
the RAP is handling these clouds the best for now. Nrn edge of the
clouds shud continue slowly moving ewd. Further S, believe clouds
will continue to dissipate and move newd. A section of the nrn
clouds from near KCOU to KUIN will likely be the last to dissipate
or advect out of the area. Across the srn portions of the CWA, CI
has already begun to move into the area and will continue to do so
overnight. However, it is a little uncertain how thick these clouds
will be.
Have trended twd the cooler guidance tonight partially because of
anticipating the clearing. However, going forecast may not be cold
enuf since temps struggled today.
Tilly
.LONG TERM: (Saturday through Next Friday)
Issued at 250 PM CDT Fri Mar 20 2015
A cdfnt shud have arrived across the nrn third of the CWA by 12z
Sat. This fnt will continue to push swd thru the day. While this may
be a cold fnt, with nearly full insolation expected, tomorrow shud
actually be warmer than today. Mdls also push the thermal ridge
across the region on Sat. The fnt begins to lift nwd on Sun as a sfc
low and associated s/w approach the region. While not high chances,
this system will bring a chance for RA across nrn portions of the
CWA Sun night and across much of the area on Mon, more probable
during the afternoon with heating.
As the trof deepens across the Plains and the LLJ increases with
what shud be an open Gulf, precip chances increase quickly Mon night
and Tues, with TS becoming more probable as well. Going forecast
PoPs may be too low attm, but have not gone higher for now due to
lack of persistence among mdl guidance. Given the amount of shear
available with the system on Tues, there is a very narrow window
where severe weather potential exists. However, given a number of
questions regarding timing with this event, will hold off mention in
products now other than that it remains to be a system to watch.
Behind the cdfnt late Wed and a secondary cdfnt on Thurs, the
potential for a very cold rain or possibly even light snow event
exists. Have kept as RA for now, but again, will be a system to
monitor.
Tilly
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 653 PM CDT Fri Mar 20 2015
Residual stratus/stratocu continues to slowly erode in a band that
originates from near Pike Counties in IL/MO to the NE into cntrl
and e cntrl IL. Meanwhile...thick cirrus continues to stream ENE
across the region from the sthrn Plains. There is the chance for
some MFVR fog around sunrise due to the recent damp conditions and
cloud cover hanging round for most of the day. Given that the
cirrus is thicker than originally thought...the threat for fog may
be less than previously thought...except at KUIN. Skies should be
clearer there than the rest of the TAF sites. Also...clouds didn`t
clear out til sunset and VSBYs remained MVFR most of the day. A
weak cold front pushes thru the terminals Sat mrng backing the
wind from SW to NE from mrng to aftn...but with speeds aob
10kts...impacts should be minimal.
Specifics for KSTL:
VFR fcst with the exception of the chance for some MVFR fog towards
12Z. Although this chance appears to be less then originally
thought with the thicker than expected cirrus overhead tonight.
Weak bndry pushes through tomorrow mrng switching the wind from SW
to E from mrng to evng though with speed expected aob 10 kts
impacts should be minimal.
2%
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 43 69 43 69 / 0 0 0 5
Quincy 39 63 38 63 / 0 0 0 5
Columbia 41 69 44 72 / 0 0 0 5
Jefferson City 41 71 44 72 / 0 0 0 5
Salem 41 68 40 62 / 0 0 0 5
Farmington 43 72 42 69 / 0 0 0 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
347 PM CDT Thu Mar 19 2015
.SHORT TERM: (Through Late Tonight)
Issued at 342 PM CDT Thu Mar 19 2015
The combination of weak mid level frontogenesis, weak low-level
convergence, and weak large scale ascent having been driving a band
of rain from eastern KS across northern MO into west central IL for
much of the afternoon. The band has managed to stay just north of
Columbia for much of the day. Present indications are that as the
attendant upstream shortwave migrates eastward this evening, the
western portion of the band will sink a bit south and impact areas
slight further south with likely or higher pops through mid-evening
persisting in the north. Later tonight the RAP and HRRR have been
very persistent for the last 4+ runs indicating another pocket of
rain will move along and just north of I-44 moving into central MO
around 05z and exiting the CWA by 10z. This appears to be in
response to mid-level convergence and frontogenesis and looks quite
reasonable, thus I have introduced some high chance to likely pops.
Otherwise clouds/stratus will hang tuf with clearing across parts of
central MO in the predawn hours, probably allowing for some fog.
Glass
.LONG TERM: (Friday through Next Thursday)
Issued at 342 PM CDT Thu Mar 19 2015
Mdls are in relatively good agreement thru the forecast period. A
cdfnt will drop into the region late Sat, bringing cooler temps for
Sun. Ahead of the fnt, have trended aoa the warmer guidance, which
is slightly warmer than the prev forecast.
Mdls prog a s/w within the nrn branch approaching the region on Mon.
Have kept PoPs low attm given the different mdl solns. For Tues, the
GFS/GEM mdls suggest any precip will remain further W, with a more
amplified flow and a more sly component of the LLJ. While the ECMWF
soln is a possibility, this does not seem likely attm. With
differences in sfc low track and strength of upper low, timing of
precip for Wed and beyond is more difficult. Have kept PoPs out of
the likely range for now given timing differences. However, it seems
that precip will be likely sometime between Tues night and Thurs
morning. Hopefully, timing will improve with future mdl cycles.
Temps are expected to remain near or above seasonal average.
Tilly
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1242 PM CDT Thu Mar 19 2015
In general, all terminals should see deteriorating flight conditions
from the afternoon into the evening. IFR should become dominate at
KCOU this afternoon, with IFR at KUIN this evening,and the St.
Louis area near 06z. Rainfall through this afternoon is expected
to remain predominately from west central MO into west central IL
with KCOU on the southern periphery and KUIN on the northern edge.
This rain area should move east and settle slowly south this
evening with drizzle and light rain become more predominate from
late evening into overnight. Stratus/cigs will also be slow to
clear and improve with KCOU/KUIN clearing on Friday morning and
the St. Louis area early Friday afternoon.
Specifics for KSTL:
Flight conditions expected to lower to MVFR this afternoon however
rain should remain just to the north. Light rain/drizzle expected to
settle in early this evening with continual lowering of cigs/vsbys
and IFR flight conditions around 06z. Stratus/cigs will be slow
to clear with clearing not expected until early Friday afternoon.
Glass
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 40 63 44 73 / 60 5 0 0
Quincy 36 59 42 68 / 70 0 0 0
Columbia 37 63 43 73 / 60 5 0 0
Jefferson City 37 63 42 74 / 60 5 0 0
Salem 41 57 43 69 / 50 10 0 0
Farmington 39 60 42 71 / 50 10 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
858 PM MDT FRI MAR 20 2015
.UPDATE...
LATEST OBSERVATIONS SHOWED THE STATIONARY BACK DOOR FRONT WAS
PARKED OVER THE NE ZONES. TEMPERATURES WERE IN THE 40S E OF THE
FRONT AND IN THE 50S TO LOWER 60S OVER THE REST OF THE AREA. IT
WAS ALSO QUITE DRY WITH DEWPOINTS IN THE TEENS AND 20S OVER MOST
OF THE AREA. E OF THE FRONT...READINGS WERE IN THE 30S. AREA
RADARS SHOWED SCATTERED RAIN AND SNOW SHOWERS MOVING THROUGH S
CANADA DUE TO JET ENERGY AND WEAK ISENTROPIC LIFT OVER THE FRONT.
A FEW ECHOES WERE ALSO NORTH OF KGGW...WHERE SPOTTERS REPORTED
SPRINKLES. THE HRRR WAS NOT PICKING UP ANY PRECIPITATION S OF THE
MT/CANADIAN BORDER...AND MODELS KEPT QPF OUT OF THE FORECAST AREA
OVERNIGHT. HOWEVER...THE NEW WRF STRENGTHENED ISENTROPIC LIFT ON
THE 300K SURFACE OVERNIGHT OVER THE FRONTAL BOUNDARY...SO GIVEN
THIS LIFT AND GENERAL PATH OF ECHOES N OF THE AREA...HAVE
INTRODUCED SOME SPRINKLES/FLURRIES INTO THE KBHK AREA AFTER 06Z
TONIGHT.
OTHERWISE A WEAK LEE TROUGH WILL REMAIN OVER THE AREA OVERNIGHT
AND HIGH CLOUDS WILL INCREASE FROM THE W THROUGH THE UPPER RIDGE.
RAISED TEMPERATURES IN A FEW LOCATIONS IN THE WESTERN ZONES DUE TO
THE ABOVE. ALSO LOWERED HUMIDITIES BASED ON LATEST DEWPOINTS AND
SREFBC GUIDANCE WHICH LOOKED REASONABLE. MADE JUST SMALL
ADJUSTMENTS TO WINDS AND SKY COVER.
A SHORTWAVE WILL MOVE THROUGH N MT SAT AFTERNOON THROUGH SAT NIGHT
BRINGING A PACIFIC COLD FRONT THROUGH THE AREA AS WELL AS
SCATTERED SHOWERS AND POSSIBLY A FEW AFTERNOON AND EVENING
THUNDERSTORMS AS LATEST SREF SHOWED POSSIBLE CAPE OF 250 J/KG.
AREA WILL DRY OUT AGAIN SUN THROUGH SUN NIGHT AS THE RIDGE
REBUILDS OVER THE REGION. ARTHUR
&&
.SHORT TERM...VALID FOR SAT AND SUN...
MODELS IN GOOD AGREEMENT IN THE SHORT PERIODS WITH A RIDGE OVER
THE PACIFIC NORTHWEST SLIDING OVER THE INTER-MOUNTAIN WEST AND
MONTANA BY SATURDAY. THIS MEANS A CONTINUATION OF WELL ABOVE
NORMAL TEMPERATURES WITH SOME BREEZY CONDITIONS DUE TO LEE SIDE
SURFACE TROUGHING. HOWEVER...THERE IS A FAST MOVING SHORT WAVE
WHICH BREAKS DOWN THE RIDGE HEADING INTO SATURDAY NIGHT. THIS WAVE
GENERALLY TRACKS ACROSS THE CANADIAN BORDER...BUT DOES DRAG SOME
ENERGY ACROSS OUR FORECAST AREA BY LATE SATURDAY AFTERNOON THROUGH
THE OVERNIGHT HOURS. ALTHOUGH WE REMAIN UNIMPRESSED WITH THE LIFT
AND DEPTH OF THE CAPE...THERE IS SOME STEEP LAPSE RATES. I DECIDED
TO ADD A MENTION OF ISOLATED THUNDER OVER OUR NW ZONES...BUT WE
ARE STILL LOOKING FOR PRIMARILY SCATTERED SHOWERS. LOW LEVELS DO
REMAIN PRETTY DRY SO WE DO NOT EXPECT ANY SIGNIFICANT
PRECIPITATION. DRIER ZONAL FLOW PREVAILS SUNDAY WITH SOMEWHAT
COOLER TEMPERATURES...AND MAYBE SOME ISOLATED INSTABILITY SHOWERS
OVER AND NEAR THE HIGH COUNTRY. BT
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
RELATIVELY MINOR CHANGES AT THIS POINT FOR THE EXTENDED FORECAST
PERIOD. MODELS REMAIN IN PRETTY GOOD AGREEMENT...BUT RUN TO RUN
INCONSISTENCIES RAISE ISSUES WITH ANY SIGNIFICANT CHANGES.
CONCENTRATION REMAINS ON BROAD PACIFIC SYSTEM CROSSING THE REGION
THROUGH THE MIDDLE OF THE WORK WEEK. MODELS HAVE SWITCHED TO AN
OPEN WAVE TYPE SIGNATURE AND SHIFTED MORE TO THE NORTHEAST. THIS
ENDS UP BEING MORE OF A GLANCING BLOW FOR MUCH OF THE
REGION...WITH BEST POTENTIAL FOR ACCUMULATING PRECIP IN HIGH
TERRAIN AS OPPOSED TO ACROSS THE EASTERN PLAINS. THAT SAID...IT
DOES APPEAR THAT THE AREA WEST OF BILLINGS COULD SEE A BIT BETTER
POTENTIAL FOR PRECIP ON TUESDAY NIGHT AND WEDNESDAY...AS
STREAMWISE VORTICITY MOVES THROUGH UNSETTLED NORTHWEST
FLOW. APPEARS TO BE PRETTY GOOD UPPER LEVEL JET SUPPORT WITH THIS
WAVE AS WELL. THIS SET UP COULD RESULT IN A PERIOD OF HEAVIER
PRECIP...WITH RAIN IN LOWER ELEVATIONS...AND QUICKLY ACCUMULATING
SNOW IN THE HIGH TERRAIN. DID INCREASE POPS ACROSS WESTERN ZONES
SLIGHTLY FOR THIS PERIOD....ESPECIALLY OVER THE MOUNTAINS. KEPT
GENERALLY SLIGHT POPS IN PLACE ELSEWHERE.
ADDITIONALLY...COLD AIR DOES NOT APPEAR TO DIG SO DEEPLY INTO THE
SOUTH CENTRAL AND SOUTH EASTERN MONTANA. THEREFORE INHERITED TEMPS
IN UPPER 40S AND LOW 50S THROUGH THURSDAY LOOK PRETTY GOOD. AN
UPPER LEVEL RIDGE BUILDS BUILDS BACK INTO THE REGION FOR FRIDAY
WITH TEMPS CLIMBING BACK TOWARD 60. AAG
&&
.AVIATION...
VFR CONDITIONS THROUGH TOMORROW AFTERNOON. BREEZY CONDITIONS WILL
RETURN TOMORROW...WITH GUSTS TO 25 KTS ALONG THE FOOTHILLS/RIDGES
MAINLY IN THE AFTERNOON. RAIN CHANCES INCREASE LATE TOMORROW
AFTERNOON AS A FRONT MOVES IN FROM THE WEST...MAINLY AROUND
LIVINGSTON BY 00Z. REIMER
&&
.PRELIMINARY POINT TEMP/POPS...
SAT SUN MON TUE WED THU FRI
-----------------------------------------------------------
BIL 044/071 040/065 037/065 037/053 029/048 026/052 032/060
00/E 31/B 03/W 43/W 33/W 22/W 11/B
LVM 044/068 036/061 036/062 036/050 028/049 023/051 031/057
02/W 31/B 03/W 44/W 33/W 22/W 11/B
HDN 036/075 038/067 034/067 037/052 028/048 023/052 029/060
00/E 41/B 02/W 44/W 33/W 22/W 11/B
MLS 036/070 040/064 033/060 037/047 025/044 022/049 026/056
10/B 41/B 02/W 55/W 32/W 22/W 11/B
4BQ 034/074 039/066 034/064 037/048 026/044 020/049 026/055
00/B 21/B 02/W 44/W 32/W 22/W 11/B
BHK 032/065 035/060 029/056 033/043 023/039 019/044 022/049
11/B 42/W 01/B 55/W 32/J 22/J 11/B
SHR 036/073 037/063 034/066 036/051 027/045 023/049 026/058
00/B 21/B 02/W 34/W 55/W 22/W 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
757 PM CDT FRI MAR 20 2015
.SYNOPSIS...
ISSUED AT 340 PM CDT FRI MAR 20 2015
H5 ANALYSIS FROM EARLIER THIS MORNING CONTINUES TO
INDICATE RIDGING ACROSS THE WESTERN CONUS WITH A CUTOFF LOW OVER
PORTIONS OF SOUTHERN BAJA CALIFORNIA. A DECENT SHORTWAVE WAS NOTED
OVER SRN COLORADO. NORTH OF THE BORDER...LOW PRESSURE WAS NOTED OVER
HUDSON BAY AND A SECOND LOW WAS NOTED SOUTH OF GREENLAND. ANOTHER
LOW WAS LOCATED SOUTH OF THE ALEUTIANS OF ALASKA WITH A TANDEM OF
SHORTWAVES ON THE SRN AND SERN PERIPHERY OF THIS FEATURE. WV IMAGERY
FROM THIS AFTERNOON IS INDICATING A NICE PLUME OF UPPER LEVEL
MOISTURE...STREAMING INTO THE PACIFIC NORTHWEST AND THE CANADIAN
ROCKIES. ANOTHER AREA OF ABUNDANT HIGH LEVEL MOISTURE WAS NOTED FROM
MEXICO INTO TEXAS AND THE SERN STATES. ACROSS THE CENTRAL
CONUS...DRYING WAS NOTED WITH CLEAR SKIES IN PLACE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA. AT THE SURFACE...LOW PRESSURE WAS
LOCATED OVER CENTRAL NORTH DAKOTA WITH A DECENT TROUGH OF LOW
PRESSURE EXTENDING SWD INTO CENTRAL AND SRN NEBRASKA. WINDS WERE
FROM THE WEST AND WEST SOUTHWEST AT 10 TO 20 MPH THIS
AFTERNOON...WITH A FEW GUSTS TO 30 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
CLEAR SKIES AND LIGHT WINDS ARE EXPECTED TONIGHT. A WEAK BACK DOOR
COLD FRONT WILL TRY TO PUSH SOUTHWEST INTO THE AREA...AND SHOULD
PUSH THROUGH THE ONEILL AREA AND STALL ALONG A LINE FROM BROKEN BOW
TO AINSWORTH LATE TONIGHT. THE ONLY NOTICEABLE DIFFERENCE ASSOCIATED
WITH THE FRONT WILL BE A SHIFT IN THE WIND TO LIGHT NORTHEAST AS THE
FRONT PASSES. TEMPERATURES WILL REALLY NOT BE MUCH DIFFERENT ON
EITHER SIDE OF THE FRONT.
A SHORTWAVE TROUGH WILL MOVE INTO MONTANA FROM THE WEST LATER
SATURDAY. AHEAD OF THIS FEATURE...SURFACE LOW PRESSURE WILL DEEPEN
AND MOVE EAST ALONG THE NE/SD BORDER DURING THE DAY. A WARM FRONT
WILL EXTEND SOUTHEAST FROM THE LOW CENTER...AND WILL ADVANCE EAST
ACROSS THE AREA DURING THE DAY SATURDAY. BOTH THE NAM AND GFS ARE IN
GOOD AGREEMENT AND HAVE THE LOW NEAR VALENTINE BY LATE
AFTERNOON...WITH THE WARM FROM ARCING SOUTHEAST FROM THE LOW CENTER
TOWARD BROKEN BOW. TO THE EAST OF THE WARM FRONT...WINDS WILL REMAIN
BACKED A BIT TO THE SOUTHEAST...WITH TEMPERATURES PROBABLY NOT
REACHING MUCH ABOVE 65 DEGREES. TO THE WEST OF THE WARM
FRONT...SOUTHWEST TO WESTERLY DOWNSLOPE WEST WINDS WILL COMBINE WITH
A PLUME OF WARM AIR ALOFT /H850MB TEMPS NEAR 17C/ WITH HIGHS WELL
INTO THE 70S. SOUNDING PROFILES INDICATE A DEEPLY MIXED
ATMOSPHERE...SO THINK A FIRE WEATHER WATCH IS NEEDED FOR AREAS ALONG
AND WEST OF THE WARM FRONT ACROSS WESTERN NEBRASKA. WINDS MAY BE
MARGINAL...BUT WITH THE VERY DRY AIR AND DEEP MIXING FEEL A WATCH IS
NEEDED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
MID RANGE...SATURDAY NIGHT THROUGH MONDAY...FOR SATURDAY NIGHT
THROUGH MONDAY...TEMPERATURES WILL BE THE MAIN FORECAST CHALLENGE.
ON SATURDAY NIGHT...SURFACE LOW PRESSURE WILL TRACK FROM THE
PANHANDLE INTO CENTRAL PORTIONS OF THE FORECAST AREA. WITH THE LOW
OVER CENTRAL PORTIONS OF THE FORECAST AREA...LOW LEVEL MOISTURE WILL
BE SHOVED EAST OF THE FORECAST AREA...WHICH WILL ALLOW MINS TO DROP
OFF INTO THE 30S SATURDAY NIGHT. IF THE LOW CONTINUES TO TREND
FARTHER EAST...WILL NEED TO DROP LOWS A BIT FURTHER AS DRIER AIR
WILL BE DRAWN FURTHER EAST FROM THE PANHANDLE. ON SUNDAY...LOW
PRESSURE WILL DROP SOUTH INTO KANSAS WITH A COLD FRONT EXTENDING
FROM SERN NEBRASKA INTO SWRN KS. WINDS WILL BE GUSTY INITIALLY
BEHIND THE FRONT WITH DECREASING WINDS IN THE AFTERNOON HOURS.
YESTERDAY...WAS CONCERNED SOME ABOUT HAZARDOUS FIRE DANGER CONDS
SUNDAY AFTERNOON...HOWEVER...BOTH THE NAM AND GFS THIS MORNING HAVE
DEW POINTS IN THE 20S BEHIND THE FRONT...WHICH IS A SLIGHT INCREASE
FROM YESTERDAY. ALSO...HIGHS TRENDED A LITTLE COOLER AS WELL...SO
MIN RH/S ARE NOT AS CRITICAL NOW. ATTM...DECIDED TO TREND HIGHS
SUNDAY A TAD COOLER WITH UPPER 50S IN THE NORTHEAST TO UPPER 60S IN
THE FAR SOUTHWEST. ON SUNDAY NIGHT...MID LEVEL WARM AIR ADVECTION
WILL BEGIN TO INCREASE IN THE PANHANDLE AND NORTHWEST OVERNIGHT
LEADING TO INCREASED CLOUDINESS AND AN OUTSIDE CHANCE OF A SHOWER IN
THE NORTHWEST. ON MONDAY SURFACE LOW PRESSURE WILL CONTINUE TO
DEEPEN ACROSS EASTERN WYOMING...LEADING TO INCREASED SOUTHEASTERLY
FLOW FLOW. WITH AN EASTERLY COMPONENT TO THE LOW LEVEL WINDS MONDAY
AND INCREASED LOW LEVEL MOISTURE ADVECTION...DECIDED TO DROP HIGHS A
TAD MONDAY FROM THE INHERITED FCST. THIS YIELDED HIGHS IN THE 60S
ACROSS THE FORECAST AREA.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY...DECENT LOW LEVEL MOISTURE
ADVECTION WILL CONTINUE MONDAY NIGHT WITH DEW POINTS REACHING THE
LOWER 40S ACROSS THE EASTERN 2/3RDS OF THE FORECAST AREA OVERNIGHT.
A LEAD SHORTWAVE WILL APPROACH THE PANHANDLE LATE MONDAY
NIGHT...LEADING TO INCREASED ELEVATED INSTABILITY. AS WAS THE CASE
YESTERDAY...H850 LI/S RANGE FROM 0 TO -2C ACROSS THE EASTERN 2/3RDS
OF THE FORECAST AREA LATE MONDAY NIGHT. INHERITED FCST HAD A MENTION
OF THUNDER AND WILL KEEP THIS INTACT WITH THE AFTERNOON PACKAGE. ON
TUESDAY...SURFACE LOW PRESSURE WILL QUICKLY LIFT INTO SOUTH DAKOTA
BY MIDDAY...FORCING THE DRYLINE INTO EASTERN NEBRASKA BY 18Z. STILL
HELD ONTO SOME SLIGHT CHANCE POPS...FOR ANY RESIDUAL THUNDERSTORMS
TUESDAY MORNING. THE AFTERNOON WILL BE DRY AND WINDY...AND WILL
LIKELY NEED SOME SORT OF FIRE HEADLINE...ESPECIALLY IN THE WEST
WHERE SFC DEW POINTS REACH THE SINGLE DIGITS BY TUESDAY AFTERNOON.
WILL CONTINUE TO HIT THE FIRE DANGER TUESDAY HARD IN THE HWO SINCE
CONFIDENCE CONTINUES TO INCREASE IN THIS HAPPENING. BEYOND
TUESDAY...THE PATTERN WILL BEGIN TO AMPLIFY ACROSS THE CONUS WITH
RIDGING ACROSS THE WESTERN THIRD OF THE CONUS AND A DEEPENING TROUGH
OVER THE GREAT LAKES SWD TO THE NRN GULF COAST. ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...MUCH COOLER TEMPS WILL ARRIVE ON WEDNESDAY
AND WILL PERSIST THROUGH FRIDAY. WITH THE MODELS TRENDING TOWARD A
DRIER PATTERN LATE NEXT WEEK...WILL LEAVE THE FCST DRY BEYOND
TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 604 PM CDT FRI MAR 20 2015
VFR IS EXPECTED ALL AREAS OVERNIGHT AND SATURDAY.
A WEAK COLD FRONT CURRENTLY MOVING THROUGH NCNTL NEB WILL MOVE
SOUTH TO NEAR NORTH PLATTE AND BECOME STATIONARY OVERNIGHT. THE
FRONT WILL THEN LIFT NORTH SATURDAY AS LOW PRESSURE DEVELOPS
ACROSS THE NRN HIGH PLAINS. GENERALLY CLEAR SKIES ARE EXPECTED
DURING THIS TIME.
&&
.FIRE WEATHER...
ISSUED AT 756 PM CDT FRI MAR 20 2015
WINDS HAVE DECREASED AS EXPECTED AND THE RED FLAG WARNING HAS BEEN
ALLOWED TO EXPIRE.
THE STRONGER WIND SPEEDS SATURDAY AFTN APPEAR TO BE NORTH OF
INTERSTATE 80 AND GENERALLY ALONG AND EAST OF HIGHWAY 61
SUGGESTING RED FLAG CONDITIONS ARE MOST LIKELY IN THIS AREA. THIS
IS BASED ON A MULTI MODEL BLEND APPROACH. THERE ARE NO STAND OUT
SOLNS EXCEPT FOR THE GEM REGIONAL WHICH SHOWED THE STRONGEST WINDS.
TONIGHTS MODEL RUNS AND THE RAP MAY TREND TOWARD THE GEM MODEL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
EVENING FOR NEZ204-206-210-219.
&&
$$
SYNOPSIS...CLB
SHORT TERM...TAYLOR
LONG TERM...CLB
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1148 PM MDT WED MAR 18 2015
.AVIATION...
06Z TAF CYCLE
THE CURRENT BATCH OF SHOWERS OVER THE NORTHERN HIGH TERRAIN AND
THE NORTHEAST PLAINS WILL EXIT SLOWLY THROUGH SUNRISE. CLEARING
BEHIND THIS WAVE MAY ALLOW FOR FOG DEVELOPMENT AROUND THE AREAS
MENTIONED EARLIER TONIGHT...FROM KAEG TO KABQ/KSAF AND KLVS.
WIDESPREAD RAINFALL BTWN 0.05 AND 0.15 WAS REPORTED AND CURRENT
DEWPOINT DEPRESSIONS ARE ON THE ORDER OF 3 SO IT LOOKS MORE
POSSIBLE WITH THIS AREA OF CLEARING. PLACED TEMPO GROUPS FOR
JUST A COUPLE HOURS TO NARROW IN ON BEST WINDOW...BEFORE THE
NEXT AREA OF CLOUD COVER INCREASING OVERHEAD FROM THE SOUTHWEST.
THURSDAY STILL LOOKS LIKE A VERY DYNAMIC DAY AFT 18Z AS A COLD
FRONT MOVES INTO THE AREA BENEATH AN APPROACHING UPPER WAVE.
WIDESPREAD SHOWERS AND THUNDERSTORMS...RAIN CHANGING TO SNOW IN
THE HIGH TERRAIN...AND GUSTY WINDS ARE EXPECTED BEHIND THE FRONT.
GUYER
&&
.PREV DISCUSSION...822 PM MDT WED MAR 18 2015...
.UPDATE...
A BACK DOOR COLD FRONT SHOULD LOWER SNOW LEVELS ACROSS THE
NORTHERN MOUNTAINS LATE THURSDAY...SO WE DECIDED TO ISSUE A WINTER
STORM WATCH. SEVERAL INCHES TO LOCALLY NEAR 1 FOOT OF SNOW WILL BE
POSSIBLE. ALSO ADDED FOG TO THE FORECAST FOR THE MORENO VALLEY
LATE TONIGHT DUE TO ALL THE MOISTURE THAT WILL SOCK IN THAT AREA.
CONSIDERED FORECASTING FOG FOR OTHER LOCATIONS...BUT SKY COVER
SHOULD STAY THICK ENOUGH TO PREVENT MUCH DEVELOPMENT.
44
&&
.PREV DISCUSSION...328 PM MDT WED MAR 18 2015...
.SYNOPSIS...
AN UPPER LOW NEAR SAN DIEGO WILL COMBINE WITH PLENTY OF LOW LEVEL MOISTURE
TO BRING SCATTERED TO NUMEROUS SHOWERS TO MUCH OF CENTRAL AND
NORTHERN NEW MEXICO TONIGHT. THIS SAME UPPER LOW WILL COMBINE
WITH ANOTHER UPPER LEVEL STORM SYSTEM DROPPING IN FROM THE
NORTHWEST ALONG WITH A BACKDOOR COLD FRONT TO PRODUCE NUMEROUS
SHOWERS TO THE NORTHERN TWO THIRDS OF NEW MEXICO THURSDAY AND
THURSDAY NIGHT. BRIEF HEAVY RAIN AND SMALL HAIL IS LIKELY WITH THE
STRONGER SHOWERS AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
PLENTIFUL RESIDUAL MOISTURE WILL KEEP SCATTERED SHOWERS IN THE
FORECAST FRIDAY...WITH A DRYING AND WARMING TREND EXPECTED FOR THE
WEEKEND.
&&
.DISCUSSION...
BAND OF LIGHT TO MODERATE RAIN EXTENDS FROM CATRON AND WESTERN
SOCORRO COUNTIES NORTHWARD INTO EASTERN CIBOLA AND SOUTHEAST
MCKINLEY COUNTIES WILL CONTINUE TO SLOWLY MOVE EASTWARD THIS EVENING.
BIG QUESTION IS WHETHER OR NOT THIS BAND WILL MAKE THE TRIP DOWNWARD
INTO THE RIO GRANDE VALLEY. 18Z NAM12 AND 18Z HRRR MODELS
INDICATING THAT THIS LINE...IN FACT...WILL MAKE IT INTO THE RGV AND
GIVEN THE CURRENT TEMP OF 66F AT THE ABQ SUNPORT AND THE 40F
DEWPOINT TEMPERATURE...SUSPECT THAT THESE HIGH RESOLUTION MODELS
ARE ON TO SOMETHING. WAVE/SPEED MAX MOVING UP FROM THE SOUTH WILL
SHIFT MAIN FOCUS FOR SHOWERS LATE TONIGHT TO THE SOUTHWEST
MOUNTAINS. ADDITIONALLY...SHOWERS WILL ALSO FOCUS OVER THE
NORTHEAST PLAINS LATE TONIGHT AND THURSDAY MORNING AS A BACKDOOR
FRONT DROPS IN. NORTHERN STREAM SHORT- WAVE TROUGH STILL PROGGED
TO PHASE WITH THE SOUTHERN STREAM CLOSED LOW OVER ERN AZ/WRN NM THURSDAY.
GOOD LAPSE RATES/INSTABILITY...ASSOCIATED LIFT FROM 100KT SUBTROPICAL
JET OVER SE NM AND COPIOUS AMOUNTS OF PACIFIC MOISTURE WILL
COMBINE WITH A BACKDOOR COLD FRONT TO GENERATE NUMEROUS SHOWERS
AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
UPPER LOW TO THE SOUTHWEST REMAINS IN TACT AND PASSES EASTWARD WELL
SOUTH OF NM WHILE THE NRN STREAM TROUGH SHEARS APART AND FILLS
OVER THE STATE FRIDAY AND FRIDAY NIGHT. PLENTY OF RESIDUAL
MOISTURE WILL COMBINE WITH DECENT LAPSE RATES/INSTABILITY AND
DAYTIME HEATING TO PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN AND NORTHERN MOUNTAINS FRIDAY AFTERNOON AND
EVENING.
ON SATURDAY...WEST COAST RIDGE CONTINUES TO PROPAGATE EAST AND FOLD
OVER AND THE RESULTING HIGHER HEIGHTS AND A VERY DRY NORTHERLY
FLOW ALOFT LIMIT SHOWERS CHANCES SATURDAY AND ALL BUT ELIMINATE
CHANCES SUNDAY INTO EARLY NEXT WEEK. MODELS AGREE THAT A DRY ZONAL
FLOW SETS UP OVER THE SOUTHWEST U.S. EARLY NEXT WEEK WITH THE
POTENTIAL FOR A TROUGH DROPPING SEWD INTO THROUGH COLORADO AND
CLIPPING THE NE AROUND MIDWEEK. 33
&&
.FIRE WEATHER...
WELL ABOVE NORMAL PWATS OVER THE AREA TO PERSIST THROUGH FRIDAY WITH
A GRADUAL DRYING TREND TAKING PWATS DOWN TO NEAR NORMAL VALUES FOR
MARCH BY THE END OF THE WEEKEND. FURTHER DRYING FORECAST EARLY NEXT
WEEK WITH THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS AS
EARLY AS TUESDAY.
CHANCES FOR WETTING PRECIPITATION WILL BE ON THE INCREASE THROUGH
THURSDAY NIGHT AS A SLOW MOVING TROUGH APPROACHES FROM THE WEST AND
A BACKDOOR COLD FRONT MAKES SOUTHWEST PROGRESS. THE 12Z MODEL
SOLUTIONS AND RESULTING MOS ARE WETTER THAN THE PAST SEVERAL RUNS
FOR CENTRAL AND NORTHERN NEW MEXICO LATE THURSDAY THROUGH THURSDAY
NIGHT DUE TO THE TIMING OF THE BACKDOOR FRONT COINCIDING WITH THE
NORTHERN STREAM TROUGH DROPPING INTO THE AREA AND PHASING WITH THE
SLOW MOVING SOUTHERN STREAM TROUGH. NOT MUCH IN THE WAY OF LIGHTNING
ACTIVITY LATE THIS AFTERNOON THROUGH TONIGHT...BUT AN UPTICK IS
EXPECTED THURSDAY AND FRIDAY.
A DRYING/WARMING TREND TO KICK-OFF SATURDAY WITH TEMPERATURES
RETURNING TO ABOVE NORMAL. A LAST ROUND OF DAYTIME HEATING TRIGGERED
CONVECTION IS FORECAST SATURDAY...ALTHOUGH COVERAGE OF WETTING
PRECIPITATION WILL BE VERY LOW. VENT RATES ARE FORECAST TO IMPROVE
THROUGH THE WEEKEND WITH THE WARMING AND INCREASING WIND PROFILE.
EARLY NEXT WEEK WILL FEATURE INCREASING WESTERLY FLOW...CONTINUED
DRYING WITH INCREASING HAINES...MIXING AND VENT RATES. POTENTIAL FOR
CRITICAL FIRE WEATHER CONDITIONS ON THE UPTREND TUESDAY AND MAY
EXTEND INTO WEDNESDAY PRIOR TO A COLD FRONT...ALTHOUGH THE PRECEDING
LEE SIDE TROUGH DOES NOT LOOK PARTICULARLY DEEP AT 1001MB. MODERATE
FORECASTER CONFIDENCE ON THE MON/TUE FORECAST AT THIS TIME GIVEN
GOOD AGREEMENT BETWEEN THE 12Z GFS AND ECMWF SOLUTIONS. 11
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY MORNING
FOR THE FOLLOWING ZONES...NMZ510>515.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1045 PM EDT FRI MAR 20 2015
.SYNOPSIS...
LOW PRESSURE PULLING AWAY FROM THE CAROLINAS WILL BE REPLACED BY
A DRYING TREND AS HIGH PRESSURE BUILDS FROM WEST SATURDAY. CLOUDS
WILL BEGIN TO THICKEN UP ON SUNDAY AS GULF MOISTURES SPREADS INTO
THE REGION...WITH RAIN LIKELY SUNDAY NIGHT THROUGH MONDAY MORNING.
SEASONABLE TEMPERATURES WILL FOLLOW FOR MUCH OF NEXT WEEK AS WEAK
HIGH PRESSURE REMAIN OVER THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM FRIDAY...THE WEAK COLD
FRONT/TROUGH AXIS HAS PROBABLY PUSHED THROUGH THE BULK OF MY
FORECAST AREA...WITH WIND DIRECTIONS RECENTLY VEERING NORTHWESTERLY
AT GEORGETOWN AND WINYAH BAY. WITH NORTHERLY WINDS ANTICIPATED TO
CONTINUE OVERNIGHT RELATIVELY COOL DRY AIR WILL BUILD SOUTHWARD. UP
ABOVE 3000 FEET AGL WINDS WILL REMAIN SOUTHWESTERLY. THERE IS GOOD
DEAL OF MOISTURE UP ABOVE THE FRONTAL SURFACE...PARTICULARLY IN THE
5000-10000 FT RANGE. DESPITE WEAK TO NONEXISTENT SYNOPTIC SUPPORT I
WILL MAINTAIN SPRINKLES IN THE FORECAST ACROSS SOUTH CAROLINA
OVERNIGHT GIVEN CURRENT RADAR COMPOSITE AND LATEST HRRR DEPICTIONS
OF SOME LIGHT RAIN CONTINUING THROUGH NEARLY DAYBREAK BEFORE PUSHING
OFFSHORE.
NO SIGNIFICANT CHANGES HAVE BEEN MADE TO TEMPERATURES...STILL
ANTICIPATED TO BOTTOM OUT IN THE UPPER 40S TO LOWER 50S...WARMEST
NEAR THE SANTEE RIVER.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 320 PM FRIDAY...IT APPEARS SUNSHINE WILL BE IN THE OFFERING
ON THE FIRST FULL DAY OF SPRING 2015...WITH MAXIMUM TEMPERATURES
RISING TO NEAR CLIMATOLOGICAL EXPECTATIONS FOR MARCH 21ST. RECENT
TIME HEIGHT DEPICTIONS OF RH/WIND SHOW COASTAL CLOUDS CANNOT BE
RULED OUT EARLY IN THE GOING SATURDAY AS NE WIND FLOW SPREADS A
MARITIME INFLUENCE INTO THE COASTAL INTERIOR. DRY AIR ABOVE 900MB
HOWEVER AND ASCENDING MARCH SUNSHINE...SHOULD BEGIN OPEN UP TO
BLUE SKIES AND AMPLE SUNSHINE MINUTES AS MIXING BECOMES VIGOROUS.
WSW WINDS IN THE UPPER ATMOSPHERE WILL BEGIN TO SPREAD CLOUDS INTO
THE CAROLINAS AS WE PROGRESS THROUGH SUNDAY...WITH RH IN THE H9-H7
LAYER REMAINING LOW A PORTION OF THE DAY. AN ATLANTIC TAP WILL
BEGIN TO MOISTEN THE SFC-H8 LAYER SUNDAY NIGHT...AND AS THIS
DEEPENS...ISENTROPIC OMEGA WILL RAMP UP AND RAIN CHANCES BOOSTED.
LOW-LEVEL WSW-SW FLOW AND EARLY OR PARTIAL SUNSHINE SUNDAY WILL
HELP BRING MAXIMUMS WELL INTO THE 60S ON SUNDAY...BUT COULD LEVEL
OFF IN THE AFTERNOON AS A HIGH OVERCAST OVERSPREADS THE REGION.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 320 PM FRIDAY...THE MID LEVEL PATTERN FOR THE EXTENDED WILL
BE QUITE PROGRESSIVE THROUGH THE FIRST PART OF THE PERIOD BEFORE
DEEP TROUGHING SETS UP BY THE END OF THE WEEK. SURFACE FEATURES
INCLUDE A FAST MOVING LOW PRESSURE SYSTEM MOVING ACROSS A
BAROCLINIC ZONE TO THE SOUTH MONDAY AS HIGH PRESSURE PRESSES INTO
OUR AREA FROM THE NORTH. I DID MAINTAIN THE LIKELY POPS...MAINLY
SOUTHERN AREAS FOR MONDAY. BEYOND THIS THE FORECAST IS DRY UNTIL
FRIDAY WHEN THE DEVELOPING EAST COAST TROUGH ARRIVES WITH WHAT
SEEMS TO BE A RELATIVELY STRONG COLD FRONT. TEMPERATURE TRENDS
REMAIN MOSTLY UNCHANGED WITH COOL READINGS FOR THE FIRST FEW DAYS
MODERATING WITH THE DEVELOPING SOUTHERLY FLOW AHEAD OF THE FRONT
FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... AS OF 00Z...POTENTIAL
FOR MVFR/IFR INTO THE EARLY OVERNIGHT HOURS DUE TO PATCHY AREAS OF
FOG AND INTERMITTENT LOW CIGS. OTHERWISE EXPECT VFR THROUGH THE
VALID TAF PERIOD.
VFR PREVAILS ACROSS THE AREA THIS EVENING WITH WEST-SOUTHWEST WINDS
AOB 8 KTS AND INTERMITTENT PATCHES OF FEW/SCT MID TO HIGH CLOUDS.
INTO THE EARLY OVERNIGHT HOURS...COULD SEE PATCHY FOG...ESPECIALLY
AT KCRE/KMYR/KFLO...BEFORE CLOUDS INCREASE AGAIN WITH -DZ POSSIBLE
AS ANOTHER BOUNDARY PUSHES THROUGH THE FORECAST AREA. AS A
RESULT...COULD SEE CONDITIONS BRIEFLY DETERIORATE TO MVFR/IFR. WINDS
THEN BECOME LIGHT LATE OVERNIGHT...GRADUALLY SHIFTING TO THE NORTH.
ON SATURDAY...EXPECT VFR TO PREVAIL WITH NORTHEASTERLY WINDS AOB 5
KTS...BECOMING SOUTHEAST IN THE AFTERNOON AOB 10 KTS...WITH
CLEARING SKIES.
EXTENDED OUTLOOK...SLIGHT CHANCE OF RAIN MONDAY WITH MVFR/IFR
CONDITIONS POSSIBLE MONDAY AND TUESDAY. OTHERWISE EXPECT VFR.
&&
.MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM
FRIDAY...WINDS CONTINUE TO VEER MORE NORTHERLY AS THE WEAK
FRONT/TROUGH AXIS DROPS SOUTHWARD. THE ACTUAL BOUNDARY IS DIFFICULT
TO DEFINE BUT PROBABLY EXTENDS FROM ABOUT 20 MILES EAST OF CAPE FEAR
THROUGH GEORGETOWN. NORTH WINDS ARE EXPECTED FOR THE REMAINDER OF
TONIGHT...VEERING MORE NORTHEASTERLY AROUND AND AFTER SUNRISE. RADAR
SHOWS SOME LIGHT RAIN OR SPRINKLES ACROSS INTERIOR EASTERN SOUTH
CAROLINA MOVING EASTWARD. SUFFICIENT MOISTURE SHOULD EXIST FOR
SCATTERED SPRINKLES SOUTH OF CAPE FEAR THROUGH THE NIGHT.
BUOY-MEASURED SEAS CURRENTLY RANGE FROM 2-4 FEET...LOWEST AT THE
NEARSHORE SUNSET BEACH BUOY AND HIGHEST AT FRYING PAN SHOALS.
SPECTRAL WAVE DATA INDICATES DOMINANT WAVE PERIOD IS 7-8 SECONDS
WITH A SMALLER SECONDARY PEAK AROUND 3 SECONDS. LITTLE CHANGE IS
ANTICIPATED THROUGH THE NIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 320 PM FRIDAY...EARLY SATURDAY A MODERATE NE WIND WILL KEEP
THE OCEAN A BIT ROUGHED UP BUT AN ADVISORY MAY NOT BE NEEDED AS
MUCH AS AN EXERCISE CAUTION STATEMENT MAY BE...FOR 15-20 KT WINDS
AND 3-5 FT SEAS. VAST IMPROVEMENT WILL BE SEEN SATURDAY AFTERNOON
AND SUNDAY AS WINDS LIGHTEN UP CONSIDERABLY. NO TSTM OR VSBY
RESTRICTIONS EXPECTED...EXCEPT RAIN MAY BEGIN TO SETTLE ACROSS THE
0-20 NM WATERS SUNDAY NIGHT...LOCALLY REDUCING VSBYS TO 4NM OR
LESS LATE SUNDAY NIGHT INTO EARLY MONDAY.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 320 PM FRIDAY...YET ANOTHER RUGGED DAY FOR THE MARINE
COMMUNITY MONDAY AS A POTENT NORTHEAST FLOW DEVELOPS AS HIGH
PRESSURE BUILDS IN FROM THE GREAT LAKES REGION. WIND SPEEDS WILL
BE 20-25 KNOTS. THE FLOW WILL CONTINUE THROUGH WEDNESDAY MORNING
BUT THE TREND WILL BE FOR SPEEDS TO WEAKEN. BY EARLY WEDNESDAY
SPEEDS WILL BE TEN KNOTS OR LESS. A RETURN FLOW DEVELOPS LATER
WEDNESDAY. SMALL CRAFT SEAS WILL DEVELOP MONDAY AND PERSIST
THROUGH MOST OF THE DAY TUESDAY. SEAS DROP TO 2-4 FEET WEDNESDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MJC
LONG TERM...SHK
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
937 PM CDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 933 PM CDT FRI MAR 20 2015
LATEST HRRR RUNS SUGGEST THE PRECIP WILL TREND NORTH OF THE BORDER
DURING THE OVERNIGHT HOURS AND DEVELOP SOUTH INTO NORTH CENTRAL
NORTH DAKOTA BEFORE SUNRISE. NEW NAM RUN SIMILAR BUT A BIT FURTHER
WEST. EITHER ONE IS WELL WITHIN THE CURRENT FORECAST ENVELOPE AND
WILL NOT MAKE ANY CHANGES TO POPS FOR THIS REASON. TEMPERATURES
AND WINDS LOOK GOOD.
UPDATE ISSUED AT 639 PM CDT FRI MAR 20 2015
STRATUS CONTINUES TO SLIDE SOUTH ACROSS THE REGION. THE STRATUS
REPRESENTS THE BAROCLINIC ZONE THAT WILL BE THE KEY IN LIFTING THE
FLOW OVER THE COOL AIR AND GENERATE SNOW ACROSS THE NORTH AND EAST.
MADE SOME ADJUSTMENTS FOR TEMPERATURES AND CLOUDS. OTHERWISE SO FAR
FORECAST TRENDING OK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
CURRENT SURFACE ANALYSIS PLACES LOW SETTLING DOWN THROUGH EASTERN
SOUTH DAKOTA WITH COLD FRONT SETTLING THROUGH SOUTHEAST INTO WEST
CENTRAL NORTH DAKOTA. CLEAR SKIES AND VERY WARM TEMPS ARE NOTED
AHEAD OF THE FRONT...WITH LOW CLOUDS AND CHILLY TEMPS BEHIND.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...CLOUD COVER WILL
CONTINUE TO SPREAD ACROSS THE AREA THROUGH THE AFTERNOON AS COOL
AIRMASS SPREADS IN. SOME LIGHT SNOW MAY START DEVELOPING LATE
TONIGHT OVER THE NORTHWEST AND SPREAD TO THE SOUTHEAST AS RIGHT
ENTRANCE REGION OF UPPER JET SLIDES THROUGH THE REGION WHILE SOME
MODEST ISENTROPIC LIFT DEVELOPS.
ON SATURDAY...CHANCES FOR SNOW CONTINUE PRIMARILY OVER THE NORTHERN
PORTIONS OF THE AREA IN MODEST ISENTROPIC LIFT AS AFOREMENTIONED JET
SLOWLY WORKS ITS WAY OFF TO THE EAST. SNOW AMOUNTS SHOULD REMAIN
LIGHT...MAINLY UNDER AN INCH. TEMPERATURES WILL AGAIN BE WARMEST OFF
TO THE SOUTHWEST WHILE COLD AIRMASS REMAINS OVER THE NORTH CENTRAL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
SEVERAL ROUNDS OF RAIN AND ACCUMULATING SNOW SATURDAY THROUGH
WEDNESDAY.
THERE IS THE POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW SATURDAY
AFTERNOON THROUGH LATE SUNDAY NIGHT. ALL OF THE MAJOR OPERATIONAL
MODELS (GFS/ECMWF/GEM/NAM/SREF) CONTINUE TO INDICATE ACCUMULATING
SNOW NORTH AND EAST OF THE MISSOURI RIVER SATURDAY THROUGH SUNDAY.
A RATHER PRONOUNCED BAROCLINIC ZONE WILL BISECT NORTH DAKOTA.
NORTH AND EAST OF THE MISSOURI RIVER TEMPERATURES ARE EXPECTED TO
REMAIN NEAR OR BELOW FREEZING. WHILE TEMPERATURES SOUTH AND WEST
OF THE RIVER SHOULD CLIMB INTO THE 40S AND 50S. UPSLOPE
FLOW...LEE CYCLOGENESIS AND A FAVORABLE CURVED UPPER LEVEL
JET...SHOULD PRODUCE WIDESPREAD 2 TO 4 INCHES ACROSS THE NORTH
AND EAST.
THE NEXT SYSTEM COULD IMPACT THE REGION MONDAY NIGHT THROUGH
WEDNESDAY. THERE IS STILL A LOT OF UNCERTAINTY IN THE EXACT TRACK
OF THIS SYSTEM. OVER THE PAST TWO MODEL RUNS THE GFS HAS
COMPLETELY FLIP FLOPPED FROM A NORTHERN SOLUTION TO A SOUTHERN
SOLUTION. THE ECMWF REMAINS FAIRLY CONSISTENT WITH A MIDDLE OF THE
ROAD SOLUTION. THERE APPEARS TO BE A GREAT DEAL OF WARM AIR WRAPPED
UP AHEAD OF THIS SYSTEM. THEREFORE...INITIAL PRECIPITATION MAY BE
ALL RAIN BEFORE CHANGING OVER TO SNOW AS COLD AIR MOVES IN BEHIND
THE LOW. TEMPERATURES WILL VARY GREATLY BASED ON THE EXACT
TRACK OF THE LOW PRESSURE CENTER. THEREFORE...WHILE HEAVY
SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG
FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROWL SET UP
ACROSS THE REGION...TOO MUCH UNCERTAINTY REMAINS TO NAIL DOWN
SPECIFIC LOCATIONS AND SNOWFALL AMOUNTS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 639 PM CDT FRI MAR 20 2015
COOL AIR HAS MOVED SOUTH INTO NORTH DAKOTA BEHIND A COLD FRONT. IFR
CONDITIONS ARE EXPECTED TO PREVAIL FROM KISN-KMOT-KJMS AS SNOW
DEVELOPS ACROSS THE NORTHERN INTO THE CENTRAL SECTIONS OF THE STATE
AFTER MIDNIGHT TONIGHT. MVFR EXPECTED FROM KDIK-KBIS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...JJS
LONG TERM...AJ
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
321 PM CDT THU MAR 19 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 257 PM CDT THU MAR 19 2015
SNOW ACROSS NORTHERN NORTH DAKOTA TONIGHT HIGHLIGHTS THE SHORT
TERM FORECAST.
THE LOW STRATUS FIELD ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WILL CONTINUE TO ERODE FROM WEST TO EAST THROUGH THE REMAINDER OF
THE AFTERNOON AND EARLY EVENING GIVEN THE LATEST VISIBLE SATELLITE
TRENDS AND 16-18 UTC HRRR ITERATIONS. THEREAFTER...A RAPIDLY
PROPAGATING CLIPPER SYSTEM WILL ENTER NORTHWESTERN NORTH DAKOTA
EARLY FRIDAY MORNING...EXITING INTO NORTH CENTRAL SOUTH DAKOTA BY
18 UTC. A BAND OF LIGHT TO MODERATE SNOW WILL DEVELOP NORTH OF THE
SURFACE LOW TRACK ACROSS NORTH CENTRAL NORTH DAKOTA IN CONJUNCTION
WITH THE ARRIVAL OF A COLD FRONT INTO NORTHERN NORTH DAKOTA. THE
GREATEST SNOWFALL TOTALS OF TWO TO THREE INCHES ARE FORECAST FOR
THE TURTLE MOUNTAINS...QUICKLY DECREASING TO THE SOUTH AND WEST.
IN THE WARM SECTOR OF THE CLIPPER ACROSS SOUTHERN NORTH
DAKOTA...HIGHS IN THE LOWER 60S ARE POSSIBLE...NEAR THE WARMER
EDGE OF THE 12 UTC SUITE...GIVEN THE BIAS TO BE TOO COLD SO FAR IN
A WELL MIXED ENVIRONMENT WITH GOOD INSOLATION THIS MONTH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU MAR 19 2015
SEVERAL PERIODS OF ACCUMULATING SNOW ARE POSSIBLE SATURDAY THROUGH
WEDNESDAY.
AN ACTIVE WEATHER PATTERN IS SETTING UP FOR WESTERN AND CENTRAL
NORTH DAKOTA THIS WEEKEND THROUGH MID-WEEK.
THE FIRST STORM...AND POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW...
WILL ARRIVE LATE SATURDAY AFTERNOON AND REMAIN THROUGH LATE SUNDAY
NIGHT. UPSLOPE FLOW...POTENT LEE CYCLOGENESIS AND FAVORABLE UPPER
LEVEL JET DYNAMICS (RIGHT ENTRANCE REGION OF A AN 80 KNOT JET)
COULD PRODUCE WIDESPREAD MODERATE SNOWFALL. THE MAIN AXIS OF
FRONTOGENESIS AND LIFT APPEARS TO BE SETTING UP MAINLY NORTH AND
EAST OF THE MISSOURI RIVER.
THE NEXT...AND POTENTIALLY STRONGER...STORM SYSTEM SHOULD IMPACT
THE REGION MONDAY NIGHT THROUGH WEDNESDAY AFTERNOON. THERE IS SOME
UNCERTAINTY IN THE EXACT TRACK OF THIS SYSTEM. THE 12 UTC GFS HAS
BEEN CONSISTENT IN SHOWING THE DEFORMATION ZONE ACROSS SOUTHERN
NORTH DAKOTA...WHILE THE 12 UTC ECMWF IS STILL SHOWING A FURTHER
NORTH SOLUTION. IT IS IMPORTANT TO NOTE THAT THE LATEST ECMWF RUN
IS TRENDING FURTHER SOUTH COMPARED TO PREVIOUS RUNS. SO IT DOES
APPEAR THAT AT LEAST SOME PORTION OF NORTH DAKOTA WILL BE
IMPACTED. HEAVY SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG
FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROW SET UP
ACROSS THE REGION. SURFACE TEMPERATURES WILL PLAY A LARGE ROLE IN
DETERMINING HOW MUCH SNOWFALL ACTUALLY ACCUMULATES. INDICATIONS
ARE THAT DURING THE DAYLIGHT HOURS TEMPERATURES ACROSS THE
NORTH DAKOTA WILL REMAIN WELL ABOVE FREEZING. DYNAMIC COOLING IN
SNOWBANDS WOULD LIKELY REDUCE AFTERNOON HEATING...BUT REGARDLESS
IT APPEARS THE MAJORITY OF ACCUMULATING SNOW WILL HAVE TO TAKE
PLACE OVERNIGHT.
NO HEADLINES WERE ISSUED WITH THIS FORECAST. IF TRENDS AND
CONFIDENCE CONTINUE TO INCREASE...HEADLINES ARE POSSIBLE THIS
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 256 PM CDT THU MAR 19 2015
PRECIPITATION WAS MOVING OUT OF THE FORECAST AREA EARLY THIS
AFTERNOON. EXPECT SOME LINGERING FLURRIES AND MVFR CIGS EARLY IN THE
PERIOD...RISING TO VFR FROM WEST TO EAST AFT 20Z. A FEW SPRINKLES
AND BAND OF LOWER CIGS WILL MOVE SOUTHEAST FROM THE MONTANA BORDER
OVERNIGHT. BREEZY CONDITIONS IN THE SOUTHWEST PART OF THE STATE WILL
GIVE WAY TO LIGHT AND VARIABLE WINDS ACROSS ALL SITES BY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM...AJ
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
100 AM CDT THU MAR 19 2015
.UPDATE...
ISSUED AT 100 AM CDT THU MAR 19 2015
MAIN CHANGE THIS UPDATE WAS TO KEEP CURRENT ON RADAR TRENDS AND
LATEST SHORT TERM HIGH RES MODELS FOR EXPECTED MOVEMENT OF AREA OF
LIGHT SNOW.
UPPER LEVEL SHORTWAVE LOW/TROUGH WAS OVER NORTHEASTERN
MONTANA/NORTHWESTERN NORTH DAKOTA. AT THE SURFACE...A LOW PRESSURE
TROUGH EXTENDED FROM WESTERN NEBRASKA TO SOUTHWESTERN NORTH DAKOTA
AND INTO EASTERN MONTANA. LOW LEVEL FLOW WAS SOUTHEASTERLY ACROSS
EASTERN SOUTH DAKOTA AND NORTH DAKOTA...WITH A STRONG H850 SOUTHERLY
WIND. LOW LEVEL LIFT EXTENDED IN AN ARC FROM THE UPPER LEVEL LOW TO
MINOT...HARVEY...JAMESTOWN/FARGO. THIS ARC IS EXPECTED TO PIVOT
NORTH...THEN WRAP AROUND THE UPPER LOW AS THE UPPER LOW MOVES
EAST/SOUTHEAST ACROSS THE STATE THIS MORNING...REACHING MINNESOTA
AROUND NOON. THE AREA OF LIGHT SNOW AND LOW CLOUDS SHOULD BE ACROSS
NORTHERN NORTH DAKOTA EARLY THIS MORNING...THEN PIVOT AROUND AND
BEGIN MOVING INTO DICKINSON AND BISMARCK BEFORE DAYBREAK...FINALLY
REACHING JAMESTOWN. HOWEVER...PRECIPITATION CHANCES SHOULD DECREASE
DURING THE MORNING AS THE UPPER LEVEL LOW/TROUGH EXITS THE AREA.
UPDATE ISSUED AT 853 PM CDT WED MAR 18 2015
PERSISTENT LIGHT SNOW WILL REQUIRE A LARGER AND LONGER PERIOD OF
SNOW ACROSS THE NORTH CENTRAL INTO THE JAMES RIVER VALLEY. DID
THAT WITH THIS UPDATE. VISIBILITIES IN THE SNOW SEEM TO CONFIRM
ITS FAIRLY LIGHT...WITH VSBYS GENERALLY A MILE OR ABOVE...ALSO
CONFIRMED BY DOT CAMERAS...AND SURFACE TEMPERATURES ARE 33 TO 36
MOST AREAS SO THERE IS SOME MELTING. NDOT TRAVEL MAP SHOWS WET AND
SLUSHY AREAS ACROSS THE AREA OF RADAR COVERAGE. SO A BOOST TO THE
POPS IS THE MAIN CHANGE FOR THE EVENING.
UPDATE ISSUED AT 636 PM CDT WED MAR 18 2015
RADAR AND SURFACE REPORTS SHOW A BAND OF MOSTLY SNOW ACROSS NORTH
CENTRAL NORTH DAKOTA. GLASGOW RADAR NOW SHOWING THE SNOW WILL TAPER
OFF AT WILLISTON. WILL INCORPORATE THESE TRENDS IN THE UPDATED
FORECAST AND GO CATEGORICAL SNOW NORTH THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
HIGHLIGHTS OF THE SHORT TERM ARE SNOWFALL AND FOG THROUGH TONIGHT.
AS OF 20 UTC...A BAND OF LIGHT TO MODERATE SNOW WAS CENTERED ALONG
A LINE FROM WATFORD CITY THROUGH JAMESTOWN. THIS BAND IS EXPECTED
TO CONTINUE TO PROPAGATE NORTHEAST THROUGH THE EVENING AND SLOWLY
WEAKEN...BECOMING CENTERED ALONG THE US HIGHWAY 2 CORRIDOR AS
DEPICTED BY THE 17-19 UTC HRRR AND 18 UTC NAM SOLUTIONS.
ADDITIONAL ACCUMULATIONS OF LESS THAN ONE INCH ARE EXPECTED GIVEN
THE VERY LOW SNOW RATIOS THAT HAVE BEEN OBSERVED THROUGH THE DAY.
DID ADD A MENTION OF FOG ACROSS THE WEST TONIGHT WITH STRATUS
BUILD DOWN AS WINDS BECOME LIGHT IN THE INVERTED TROUGH AXIS.
SCATTERED RAIN AND SNOW SHOWERS MAY LINGER INTO THURSDAY MORNING
IN ASSOCIATION WITH THE DEPARTING UPPER LEVEL WAVE...WITH MOSTLY
SUNNY CONDITIONS EXPECTED BY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
AN ACTIVE LONG TERM PERIOD. THE HUDSON BAY LOW SHIFTS EAST THROUGH
THE PERIOD ALLOWING FOR A MORE ENERGETIC/MOIST PACIFIC FLOW WITH
SEVERAL SHORTWAVES TO MOVE ACROSS NORTH DAKOTA. ONE LAST SHORTWAVE
ASSOCIATED WITH THE HUDSON BAY LOW WILL PUSH A CLIPPER SYSTEM ACROSS
MAINLY NORTH CENTRAL INTO EAST CENTRAL NORTH DAKOTA FRIDAY. HAVE
INCREASED POPS TO LIKELY CATEGORY IN THE NORTH CENTRAL/TURTLE
MOUNTAINS WITH ALL MODELS DEPICTING THE SHORTWAVE AND ASSOCIATED
PRECIPITATION ACROSS THIS AREA. COULD BE AROUND ONE INCH IN THE
TURTLE MOUNTAINS. POPS TAPER OFF TO BELOW MEASURABLE FARTHER SOUTH
AND WEST. AS THE FLOW TRANSITIONS FROM NORTHWEST TO ZONAL FLOW...A
SERIES OF SHORTWAVES SHIFTING EAST FROM THE PACIFIC QUICKLY MOVE
TOWARD NORTH DAKOTA. A WEAK SHORTWAVE SLIDES THROUGH SATURDAY WITH A
CHANCE OF SNOW/RAIN MOSTLY AFFECTING NORTHWEST THROUGH NORTH CENTRAL
NORTH DAKOTA. THEREAFTER...TWO SIGNIFICANT MID LEVEL SHORTWAVES WILL
NEED MONITORING. THE FIRST SHORTWAVE COMES THROUGH WESTERN AND
CENTRAL NORTH DAKOTA...NEGATIVELY TILTED...SUNDAY INTO SUNDAY NIGHT.
THIS WILL PRODUCE WIDESPREAD SNOW ACROSS CENTRAL NORTH DAKOTA WITH
THE GFS AND ECMWF DEPICTING TWO TO THREE TENTHS OF LIQUID...OR
POSSIBLY 2 TO 3.5 INCHES OF SNOW FOR PORTIONS OF CENTRAL NORTH
DAKOTA. TEMPERATURES SHOULD BE WARMER SOUTHWEST FOR SNOW CHANGING
OVER TO RAIN IN THE AFTERNOON. A BRIEF TRANSITORY RIDGE SLIDES BY
MONDAY/MONDAY NIGHT BEFORE THE NEXT POTENT SHORTWAVE ARRIVES
TUESDAY/WEDNESDAY. THE GFS IS FARTHER SOUTH WITH THE LOW PRESSURE
COMPLEX...SLIDING THROUGH CENTRAL/NORTHERN SOUTH DAKOTA RESULTING IN
COLDER AIR TO BE DRAWN INTO THE LOW WITH WIDESPREAD SNOW FOR
CENTRAL/SOUTHERN NORTH DAKOTA. THE ECMWF IS FARTHER NORTH WITH THIS
SYSTEM AND PRODUCES SOME LIGHT PRECIPITATION IN THE WARM AIR
ADVECTION TUESDAY FOLLOWED BY A DRY SLOT. SOME SNOW SHOWERS DEVELOP
ON THE BACK SIDE OF THE LOW WITH COLD AIR ADVECTION COMMENCING
TUESDAY NIGHT INTO WEDNESDAY. OVERALL THE ECMWF IS WEAKER WITH
REGARDS TO QPF THAN THE GFS. WILL ALSO NEED TO MONITOR THIS IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 100 AM CDT THU MAR 19 2015
TROUGH OF LOW PRESSURE CONTINUED LIFTING NORTH ACROSS NORTHERN NORTH
DAKOTA THIS MORNING. AS THE SYSTEM PIVOTS AND BEGINS MOVING
SOUTHEAST DURING THE NIGHTTIME HOURS MVFR/IFR CONDITIONS WILL
RETURN TO TAF SITES. LIGHT SNOW AND FOG WILL REDUCE VSBYS AND
CEILINGS TO IFR CONDITIONS ACROSS KISN AND KMOT UNTIL AROUND 18Z.
KDIK- KBIS-KJMS WILL GENERALLY SEE VFR AT 06Z UNTIL MVFR AND IFR
CIGS MOVE INTO KDIK AROUND 08Z...KBIS 09Z-11Z...AND REACHING KJMS
AROUND 16Z. VFR CONDITIONS EXPECTED TO DEVELOP FROM NORTHWEST TO
SOUTHEAST...BEGINNING AT 18Z NORTHWEST AND FINALLY EXITING KJMS BY
AROUND 00Z.
&&
.HYDROLOGY...
ISSUED AT 342 PM CDT WED MAR 18 2015
THE WILLOW CREEK NEAR WILLOW CITY IS FORECAST TO CONTINUE TO RISE
INTO THURSDAY...CRESTING JUST BELOW FLOOD STAGE. HOWEVER...PRECIPITATION
THIS WEEKEND INTO NEXT WEEK MAY LEAD TO ADDITIONAL RISES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...AYD
LONG TERM...KS
AVIATION...JV
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS NORMAN OK
542 PM CDT THU MAR 19 2015
.AVIATION...
IFR CONDITIONS IN FOG AND LOW CEILINGS ARE EXPECTED TO LAST
THROUGH THE EVENING AND INTO EARLY FRIDAY. CONDITIONS WILL SLOWLY
IMPROVE NORTH TO SOUTH ACROSS OKLAHOMA LATER FRIDAY MORNING.
ISOLATED THUNDERSTORMS WILL END AROUND WICHITA FALLS BEFORE
200600. LIGHT RAIN WILL MOVE EAST OF OKLAHOMA CITY FRIDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 356 PM CDT THU MAR 19 2015/
DISCUSSION...
THE FIRST POINT OF CONCERN IS THE RISK OF THUNDERSTORMS INTO THIS
EVENING...MAINLY IN OUR TEXAS COUNTIES. THE RECENTLY-ISSUED
MESOSCALE DISCUSSION FROM SPC PROVIDES DETAILS ON THE SITUATION
THERE. IN ADDITION...THE HRRR MODEL SUPPORTS STORM DEVELOPMENT
FROM NOW INTO THE LATE EVENING...INCLUDING A FEW NON-SEVERE STORMS
NORTH ALMOST AS FAR AS I-40.
A COLD FRONT...WHICH IS PART OF THE REASON FOR THE RAIN AND
STORMS...WILL STRENGTHEN AND EDGE SOUTH THIS EVENING AND
OVERNIGHT...EVENTUALLY PUSHING THE MAIN PRECIPITATION AREA SOUTH.
HOWEVER...THE FRONT WILL NOT GET ALL THAT FAR INTO TEXAS...AND
SUFFICIENT MOISTURE/LIFT WILL REMAIN IN PLACE TO KEEP A CHANCE OF
RAIN IN OUR SOUTHERN COUNTIES WELL INTO THE WEEKEND.
ON TUESDAY...ANOTHER STORM SYSTEM WILL TAKE SHAPE...AND TUESDAY
SHOULD BE A WINDY DAY WITH A MODERATE TO STRONG CAPPING INVERSION.
THIS WILL HOLD DOWN THE CHANCES FOR STORMS UNTIL A COLD FRONT
ARRIVES LATE TUESDAY INTO WEDNESDAY. STORM CHANCES WILL RETURN
WITH THIS FRONT...ALTHOUGH IT WILL STILL HAVE THE CAP TO CONTEND
WITH.
BEYOND WEDNESDAY...MODELS DIVERGE QUITE A BIT...ALTHOUGH THE GFS
DOES NOT APPEAR TO HAVE A GOOD BACKING FROM ITS OWN ENSEMBLE.
SO...WE CAN PROBABLY SAFELY IGNORE THE SNOWFALL THAT IT GENERATES
ON THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 66 47 70 / 70 10 0 10
HOBART OK 42 62 46 70 / 70 10 0 10
WICHITA FALLS TX 49 62 50 68 / 90 20 10 20
GAGE OK 37 70 43 74 / 50 10 0 0
PONCA CITY OK 39 71 44 73 / 50 10 0 0
DURANT OK 52 62 53 66 / 90 40 20 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
356 PM CDT THU MAR 19 2015
.DISCUSSION...
THE FIRST POINT OF CONCERN IS THE RISK OF THUNDERSTORMS INTO THIS
EVENING...MAINLY IN OUR TEXAS COUNTIES. THE RECENTLY-ISSUED
MESOSCALE DISCUSSION FROM SPC PROVIDES DETAILS ON THE SITUATION
THERE. IN ADDITION...THE HRRR MODEL SUPPORTS STORM DEVELOPMENT
FROM NOW INTO THE LATE EVENING...INCLUDING A FEW NON-SEVERE STORMS
NORTH ALMOST AS FAR AS I-40.
A COLD FRONT...WHICH IS PART OF THE REASON FOR THE RAIN AND
STORMS...WILL STRENGTHEN AND EDGE SOUTH THIS EVENING AND
OVERNIGHT...EVENTUALLY PUSHING THE MAIN PRECIPITATION AREA SOUTH.
HOWEVER...THE FRONT WILL NOT GET ALL THAT FAR INTO TEXAS...AND
SUFFICIENT MOISTURE/LIFT WILL REMAIN IN PLACE TO KEEP A CHANCE OF
RAIN IN OUR SOUTHERN COUNTIES WELL INTO THE WEEKEND.
ON TUESDAY...ANOTHER STORM SYSTEM WILL TAKE SHAPE...AND TUESDAY
SHOULD BE A WINDY DAY WITH A MODERATE TO STRONG CAPPING INVERSION.
THIS WILL HOLD DOWN THE CHANCES FOR STORMS UNTIL A COLD FRONT
ARRIVES LATE TUESDAY INTO WEDNESDAY. STORM CHANCES WILL RETURN
WITH THIS FRONT...ALTHOUGH IT WILL STILL HAVE THE CAP TO CONTEND
WITH.
BEYOND WEDNESDAY...MODELS DIVERGE QUITE A BIT...ALTHOUGH THE GFS
DOES NOT APPEAR TO HAVE A GOOD BACKING FROM ITS OWN ENSEMBLE.
SO...WE CAN PROBABLY SAFELY IGNORE THE SNOWFALL THAT IT GENERATES
ON THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 66 47 70 / 70 10 0 10
HOBART OK 42 62 46 70 / 70 10 0 10
WICHITA FALLS TX 49 62 50 68 / 90 20 10 20
GAGE OK 37 70 43 74 / 50 10 0 0
PONCA CITY OK 39 71 44 73 / 50 10 0 0
DURANT OK 52 62 53 66 / 90 40 20 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/23
AREA FORECAST DISCUSSION
NWS MEDFORD OR
902 PM PDT FRI MAR 20 2015
.DISCUSSION...A BAND OF SHOWERS ARE MOVING INTO SOUTHERN OREGON
AND NORTHERN CALIFORNIA. THIS BAND HAD PRODUCED MODERATE SHOWERS
AT THE COAST WITH LIGHTNING STRIKES IN CURRY COUNTY. SHORT TERM
MODEL TAKES THIS BAND THROUGH THE CASCADES AROUND MIDNIGHT, THEN
THROUGH QUARTZ MTN AREA INTO LAKE COUNTY AROUND 4-5 AM SATURDAY.
THE SOUTHERN PORTION OF THIS BAND MAY NOT HOLD TOGETHER PAST THE
CASCADES WITH GUIDANCE SHOWING VERY LITTLE RAIN IN TULELAKE AND
MODOC COUNTY.
WE HAD UPDATED THE GRIDS EARLIER TO INDICATE THUNDERSTORMS AT THE
COAST THIS EVENING. OTHERWISE FORECAST IS ON TRACK WITH SOME BREAK
SATURDAY BEFORE NEXT SYSTEM ARRIVES ON SUNDAY AND MONDAY. SHOWERS
WILL CONTINUE INTO THE MIDDLE OF NEXT WEEK BEFORE DRYING RETURNS.
/FB
&&
.AVIATION...FOR THE 21/00Z TAF CYCLE...AREAS OF MVFR WITH LOCAL IFR
CIGS/VSBYS ARE EXPECTED ALONG THE COAST THIS EVENING...THEN WILL
SPREAD INLAND TO THE CASCADES THROUGH 06Z...WITH HIGHER TERRAIN
BECOMING OBSCURED. THESE AREAS WILL CLEAR TO VFR BY SATURDAY
AFTERNOON. EAST OF THE CASCADES...VFR CONDITIONS WILL PREVAIL
THROUGH SATURDAY...BUT AREAS OF HIGHER TERRAIN WILL BECOME OBSCURED
AFTER 06Z TONIGHT. SPILDE
&&
.MARINE...UPDATED 230 PM PDT FRIDAY 20 MAR 2015...A COLD FRONT WITH
MODERATE WINDS AND HAZARDOUS SEAS WILL MOVE THROUGH THE WATERS THIS
EVENING WITH A SLIGHT CHANCE OF THUNDERSTORMS. WINDS AND SEAS WILL
GRADUALLY DIMINISH OVERNIGHT INTO SATURDAY NIGHT AS WEAK HIGH
PRESSURE BUILDS IN. ANOTHER COLD FRONT WILL MOVE ONSHORE SUNDAY
MORNING AND THIS WILL BRING ANOTHER ROUND OF SOUTH WINDS AND CHOPPY
SEAS SATURDAY NIGHT INTO SUNDAY. WINDS MAY APPROACH GALE FORCE
SUNDAY MORNING. A SERIES OF WEAKER DISTURBANCES WILL MOVE THROUGH
THE WATERS MONDAY AND TUESDAY. SPILDE
&&
.PREV DISCUSSION... /ISSUED 505 PM PDT FRI MAR 20 2015/
UPDATE...A FEW LIGHTNING STRIKES ARE SHOWING UP ALONG THE COOS
AND CURRY COAST AS WELL AS THE COASTAL WATERS THIS EVENING. AS
SUCH, THE FORECAST HAS BEEN UPDATED TO REFLECT THE CURRENT
TRENDS. ALSO THE AVIATION SECTION BELOW WAS REFRESHED. SPILDE
SHORT TERM...AN ACTIVE PATTERN IS IN THE WORKS STARTING THIS
EVENING AND LASTING INTO THE EARLY PART OF NEXT WEEK. THE FIRST
FRONT IS MAKING HEADWAY TOWARDS THE OREGON COAST. SO FAR NO RAINFALL
HAS BEEN REPORTED AT ANY OF THE COASTAL LOCATIONS, BUT THE COMPOSITE
RADAR IMAGES FROM MEDFORD AND EUREKA SHOW THE LEADING EDGE OF
RAINFALL MOVING INTO THE OUTER MARINE WATERS. THE LATEST HRRR MODEL
SHOWS RAINFALL ARRIVING AT THE COAST AROUND 5 PM PDT THEN PUSHING
INLAND IN COOS AND CURRY COUNTY DURING THE EVENING. THE MODELS SHOW
WEAK ELEVATED INSTABILITY OVER THE MARINE WATERS THIS EVENING, BUT
HAVE NOT SEEN ANY LIGHTNING STRIKES OVER THE WATERS AND THE COLD AIR
ALOFT IS STILL TO THE WEST, SO HAVE DECIDED TO REMOVE IT FROM THE
FORECAST THIS EVENING. THE COLD FRONT WILL CONTINUE TO MOVE
SOUTHEAST TONIGHT WITH RAIN AND HIGHER ELEVATION MOUNTAIN SNOW
MAINLY ALONG AND WEST OF THE CASCADES. SNOW LEVELS START OUT AROUND
7000 FEET THIS EVENING, LOWERING TO AROUND 5500 FEET BY SATURDAY
MORNING, SO WOULD NOT BE SURPRISED TO SEE ROADS SNOW COVERED NEAR
DIAMOND LAKE AND CRATER LAKE AREAS BY DAYBREAK SATURDAY.
THE UPPER TROUGH WILL SWING THROUGH SATURDAY MORNING THEN THE MODELS
SHOW WEAK RIDGING BUILDING IN SATURDAY AFTERNOON. THIS SHOULD RESULT
IN DECREASING PRECIPITATION LATE SATURDAY MORNING WITH DRY
CONDITIONS MOST HOURS AND LOCATIONS SATURDAY AFTERNOON. ALSO THERE
WILL BE SLIGHT WARMING ALOFT WHICH WILL REDUCE THE AMOUNT OF
INSTABILITY.
THE NAM SHOWS PRECIPITATION BREAKING OUT OVER NORTHERN CAL AND
SOUTHWEST OREGON SATURDAY NIGHT. THE GFS ALSO SHOWS THIS, BUT TO
A MUCH LESSER EXTENT AND THE EC KEEPS IT DRY. FOR NOW DID NOT MAKE
ANY SIGNIFICANT CHANGES TO THE FORECAST, BUT DID EXPEND POPS
FURTHER NORTH AND NORTHEAST.
ANOTHER, BUT STRONGER FRONT WILL ARRIVE SUNDAY BRINGING ANOTHER
ROUND OF PRECIPITATION TO THE COAST LATE SUNDAY MORNING, MOVING
INLAND SUNDAY AFTERNOON. A MUCH COLDER AIR MASS ALOFT (THE COLDEST
WE HAVE SEEN IN A WHILE) WILL MOVE IN SUNDAY NIGHT AND REMAIN
OVERHEAD THROUGH MONDAY. SNOW LEVELS WILL FALL FROM AROUND 6000
FEET TO 4000 FEET SUNDAY NIGHT WITH PLENTY OF SHOWERS. SO IF YOU
PLAN ON TRAVELING ON HIGHWAY 140 NEAR LAKE OF THE WOODS, HIGHWAY
62 NEAR CRATER LAKE, HIGHWAY 130 NEAR DIAMOND LAKE AND SISKIYOU
SUMMIT SUNDAY NIGHT, BE PREPARED FOR WINTRY TRAVEL.
MODELS CONTINUE TO SHOW 500 MB TEMPERATURES NEAR OR A LITTLE LOWER
THEN -30 C MOVING OVER THE AREA DURING THE DAY MONDAY. IN ADDITION
NEGATIVE LIFTED INDICES ARE EXPECTED. ALL THIS IN COMBINATION WITH
SURFACE HEATING WILL CREATE ENOUGH INSTABILITY FOR AT LEAST ISOLATED
THUNDERSTORMS MONDAY AFTERNOON. RIGHT NOW, THE BEST CHANCE FOR
THUNDERSTORMS WILL BE ALONG AND EAST OF THE CASCADES FROM AROUND
CRATER LAKE NORTH, THE NORTHERN HALF OF KLAMATH COUNTY AND MOST OF
LAKE COUNTY, BUT THE DETAILS ON THIS ARE LIKELY TO CHANGE AS WE GET
CLOSER TO MONDAY.
IF NOTHING ELSE, WE`LL SEE SHOWERS INCREASE IN COVERAGE WITH SOME
MODERATE TO HEAVY PRODUCING SMALL HAIL, ESPECIALLY IN THE AFTERNOON.
SNOW LEVELS WILL START AROUND 4000 FEET MONDAY MORNING, THEN WE`LL
HAVE A DIURNAL INCREASE TO AROUND 4500 FEET IN THE AFTERNOON.
HOWEVER, THEY COULD TEMPORARILY LOWER TO 4000 FEET OR LESS IN
HEAVIER SHOWERS. IF THIS HAPPENS, THEN LAKE OF THE WOODS AND
SISKIYOU SUMMIT COULD SEE RAIN SHOWERS TURN TO WET SNOW SHOWERS THAT
COULD BRIEFLY ACCUMULATE ON THE ROADS.
A COOL MOIST NORTHWEST FLOW CONTINUES MONDAY NIGHT WITH THE BULK OF
THE PRECIPITATION ALONG AND WEST OF THE CASCADES. THE GFS AND EC
SHOW A WEAK LOW DEVELOPING AND MOVING TOWARDS NORTHWEST OREGON.
THIS WILL BRING ANOTHER ROUND OF MODERATE PRECIPITATION AND
THERE`S A CHANCE SNOW LEVELS COULD COME UP AS A WARM FRONT MOVES
THROUGH. -PETRUCELLI
LONG TERM...TUESDAY THROUGH FRIDAY.
THE EXTENDED PERIOD WILL START OFF WITH NEARLY ZONAL FLOW ALOFT OVER
THE PACIFIC NORTHWEST. A LONG WAVE RIDGE WILL BEGIN TO BUILD
OFFSHORE BETWEEN 130W AND 140W TUESDAY...AND IT WILL AMPLIFY AS IT
MOVES SLOWLY EAST. FLOW ALOFT WILL BECOME NORTHWESTERLY OVER THE
PACIFIC NORTHWEST.
AFTER THE LAST OF THE SHORT WAVES EMBEDDED IN THE ZONAL FLOW MOVES
THROUGH TUESDAY NIGHT INTO WEDNESDAY...EXPECT DRY WEATHER TO DEVELOP
ALONG WITH A WARMING TREND WEDNESDAY INTO THURSDAY.
BOTH THE EC AND THE GFS BREAK THE LONG WAVE RIDGE AXIS TO THE EAST
OF THE MEDFORD CWA SOMETIME THURSDAY. AFTER THIS THE MODEL
SOLUTIONS DIVERGE. THE EC IS THE MOST PROGRESSIVE...BRINGING THE
NEXT SHORT WAVE ONSHORE FRIDAY MORNING. THE GFS DELAYS THIS WAVE
UNTIL FRIDAY EVENING.
THE ENSEMBLES SHOW QUITE A BIT OF SPREAD IN THE MEMBERS FROM FRIDAY
ON...ESPECIALLY THE EC. SO...CONFIDENCE ON THE TIMING OF THE
INCOMING SYSTEM IS LOW TO MODERATE.
AT THIS TIME...WILL GO THE MIDDLE ROAD AND BRING PRECIPITATION BACK
INTO THE FORECAST FRIDAY. -JRS
AVIATION...FOR THE 21/00Z TAF CYCLE...AREAS OF MVFR WITH LOCAL
IFR CIGS/VSBYS ARE EXPECTED ALONG THE COAST THIS EVENING...THEN
WILL SPREAD INLAND TO THE CASCADES THROUGH 06Z...WITH HIGHER
TERRAIN BECOMING OBSCURED. THESE AREAS WILL CLEAR TO VFR BY
SATURDAY AFTERNOON. EAST OF THE CASCADES...VFR CONDITIONS WILL
PREVAIL THROUGH SATURDAY...BUT AREAS OF HIGHER TERRAIN WILL BECOME
OBSCURED AFTER 06Z TONIGHT. SPILDE
MARINE...UPDATED 230 PM PDT FRIDAY 20 MAR 2015...A COLD FRONT WITH
MODERATE WINDS AND HAZARDOUS SEAS WILL MOVE THROUGH THE WATERS THIS
EVENING WITH A SLIGHT CHANCE OF THUNDERSTORMS. WINDS AND SEAS WILL
GRADUALLY DIMINISH OVERNIGHT INTO SATURDAY NIGHT AS WEAK HIGH
PRESSURE BUILDS IN. ANOTHER COLD FRONT WILL MOVE ONSHORE SUNDAY
MORNING AND THIS WILL BRING ANOTHER ROUND OF SOUTH WINDS AND CHOPPY
SEAS SATURDAY NIGHT INTO SUNDAY. WINDS MAY APPROACH GALE FORCE
SUNDAY MORNING. A SERIES OF WEAKER DISTURBANCES WILL MOVE THROUGH
THE WATERS MONDAY AND TUESDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 PM PDT THIS EVENING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370-376.
$$
FJB/MAS/MAS
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
505 PM PDT FRI MAR 20 2015
.UPDATE...A FEW LIGHTNING STRIKES ARE SHOWING UP ALONG THE COOS
AND CURRY COAST AS WELL AS THE COASTAL WATERS THIS EVENING. AS
SUCH, THE FORECAST HAS BEEN UPDATED TO REFLECT THE CURRENT
TRENDS. ALSO THE AVIATION SECTION BELOW WAS REFRESHED. SPILDE
.SHORT TERM...AN ACTIVE PATTERN IS IN THE WORKS STARTING THIS
EVENING AND LASTING INTO THE EARLY PART OF NEXT WEEK. THE FIRST
FRONT IS MAKING HEADWAY TOWARDS THE OREGON COAST. SO FAR NO RAINFALL
HAS BEEN REPORTED AT ANY OF THE COASTAL LOCATIONS, BUT THE COMPOSITE
RADAR IMAGES FROM MEDFORD AND EUREKA SHOW THE LEADING EDGE OF
RAINFALL MOVING INTO THE OUTER MARINE WATERS. THE LATEST HRRR MODEL
SHOWS RAINFALL ARRIVING AT THE COAST AROUND 5 PM PDT THEN PUSHING
INLAND IN COOS AND CURRY COUNTY DURING THE EVENING. THE MODELS SHOW
WEAK ELEVATED INSTABILITY OVER THE MARINE WATERS THIS EVENING, BUT
HAVE NOT SEEN ANY LIGHTNING STRIKES OVER THE WATERS AND THE COLD AIR
ALOFT IS STILL TO THE WEST, SO HAVE DECIDED TO REMOVE IT FROM THE
FORECAST THIS EVENING. THE COLD FRONT WILL CONTINUE TO MOVE
SOUTHEAST TONIGHT WITH RAIN AND HIGHER ELEVATION MOUNTAIN SNOW
MAINLY ALONG AND WEST OF THE CASCADES. SNOW LEVELS START OUT AROUND
7000 FEET THIS EVENING, LOWERING TO AROUND 5500 FEET BY SATURDAY
MORNING, SO WOULD NOT BE SURPRISED TO SEE ROADS SNOW COVERED NEAR
DIAMOND LAKE AND CRATER LAKE AREAS BY DAYBREAK SATURDAY.
THE UPPER TROUGH WILL SWING THROUGH SATURDAY MORNING THEN THE MODELS
SHOW WEAK RIDGING BUILDING IN SATURDAY AFTERNOON. THIS SHOULD RESULT
IN DECREASING PRECIPITATION LATE SATURDAY MORNING WITH DRY
CONDITIONS MOST HOURS AND LOCATIONS SATURDAY AFTERNOON. ALSO THERE
WILL BE SLIGHT WARMING ALOFT WHICH WILL REDUCE THE AMOUNT OF
INSTABILITY.
THE NAM SHOWS PRECIPITATION BREAKING OUT OVER NORTHERN CAL AND
SOUTHWEST OREGON SATURDAY NIGHT. THE GFS ALSO SHOWS THIS, BUT TO
A MUCH LESSER EXTENT AND THE EC KEEPS IT DRY. FOR NOW DID NOT MAKE
ANY SIGNIFICANT CHANGES TO THE FORECAST, BUT DID EXPEND POPS
FURTHER NORTH AND NORTHEAST.
ANOTHER, BUT STRONGER FRONT WILL ARRIVE SUNDAY BRINGING ANOTHER
ROUND OF PRECIPITATION TO THE COAST LATE SUNDAY MORNING, MOVING
INLAND SUNDAY AFTERNOON. A MUCH COLDER AIR MASS ALOFT (THE COLDEST
WE HAVE SEEN IN A WHILE) WILL MOVE IN SUNDAY NIGHT AND REMAIN
OVERHEAD THROUGH MONDAY. SNOW LEVELS WILL FALL FROM AROUND 6000
FEET TO 4000 FEET SUNDAY NIGHT WITH PLENTY OF SHOWERS. SO IF YOU
PLAN ON TRAVELING ON HIGHWAY 140 NEAR LAKE OF THE WOODS, HIGHWAY
62 NEAR CRATER LAKE, HIGHWAY 130 NEAR DIAMOND LAKE AND SISKIYOU
SUMMIT SUNDAY NIGHT, BE PREPARED FOR WINTRY TRAVEL.
MODELS CONTINUE TO SHOW 500 MB TEMPERATURES NEAR OR A LITTLE LOWER
THEN -30 C MOVING OVER THE AREA DURING THE DAY MONDAY. IN ADDITION
NEGATIVE LIFTED INDICES ARE EXPECTED. ALL THIS IN COMBINATION WITH
SURFACE HEATING WILL CREATE ENOUGH INSTABILITY FOR AT LEAST ISOLATED
THUNDERSTORMS MONDAY AFTERNOON. RIGHT NOW, THE BEST CHANCE FOR
THUNDERSTORMS WILL BE ALONG AND EAST OF THE CASCADES FROM AROUND
CRATER LAKE NORTH, THE NORTHERN HALF OF KLAMATH COUNTY AND MOST OF
LAKE COUNTY, BUT THE DETAILS ON THIS ARE LIKELY TO CHANGE AS WE GET
CLOSER TO MONDAY.
IF NOTHING ELSE, WE`LL SEE SHOWERS INCREASE IN COVERAGE WITH SOME
MODERATE TO HEAVY PRODUCING SMALL HAIL, ESPECIALLY IN THE AFTERNOON.
SNOW LEVELS WILL START AROUND 4000 FEET MONDAY MORNING, THEN WE`LL
HAVE A DIURNAL INCREASE TO AROUND 4500 FEET IN THE AFTERNOON.
HOWEVER, THEY COULD TEMPORARILY LOWER TO 4000 FEET OR LESS IN
HEAVIER SHOWERS. IF THIS HAPPENS, THEN LAKE OF THE WOODS AND
SISKIYOU SUMMIT COULD SEE RAIN SHOWERS TURN TO WET SNOW SHOWERS THAT
COULD BRIEFLY ACCUMULATE ON THE ROADS.
A COOL MOIST NORTHWEST FLOW CONTINUES MONDAY NIGHT WITH THE BULK OF
THE PRECIPITATION ALONG AND WEST OF THE CASCADES. THE GFS AND EC
SHOW A WEAK LOW DEVELOPING AND MOVING TOWARDS NORTHWEST OREGON.
THIS WILL BRING ANOTHER ROUND OF MODERATE PRECIPITATION AND
THERE`S A CHANCE SNOW LEVELS COULD COME UP AS A WARM FRONT MOVES
THROUGH. -PETRUCELLI
.LONG TERM...TUESDAY THROUGH FRIDAY.
THE EXTENDED PERIOD WILL START OFF WITH NEARLY ZONAL FLOW ALOFT OVER
THE PACIFIC NORTHWEST. A LONG WAVE RIDGE WILL BEGIN TO BUILD
OFFSHORE BETWEEN 130W AND 140W TUESDAY...AND IT WILL AMPLIFY AS IT
MOVES SLOWLY EAST. FLOW ALOFT WILL BECOME NORTHWESTERLY OVER THE
PACIFIC NORTHWEST.
AFTER THE LAST OF THE SHORT WAVES EMBEDDED IN THE ZONAL FLOW MOVES
THROUGH TUESDAY NIGHT INTO WEDNESDAY...EXPECT DRY WEATHER TO DEVELOP
ALONG WITH A WARMING TREND WEDNESDAY INTO THURSDAY.
BOTH THE EC AND THE GFS BREAK THE LONG WAVE RIDGE AXIS TO THE EAST
OF THE MEDFORD CWA SOMETIME THURSDAY. AFTER THIS THE MODEL
SOLUTIONS DIVERGE. THE EC IS THE MOST PROGRESSIVE...BRINGING THE
NEXT SHORT WAVE ONSHORE FRIDAY MORNING. THE GFS DELAYS THIS WAVE
UNTIL FRIDAY EVENING.
THE ENSEMBLES SHOW QUITE A BIT OF SPREAD IN THE MEMBERS FROM FRIDAY
ON...ESPECIALLY THE EC. SO...CONFIDENCE ON THE TIMING OF THE
INCOMING SYSTEM IS LOW TO MODERATE.
AT THIS TIME...WILL GO THE MIDDLE ROAD AND BRING PRECIPITATION BACK
INTO THE FORECAST FRIDAY. -JRS
&&
.AVIATION...FOR THE 21/00Z TAF CYCLE...AREAS OF MVFR WITH LOCAL
IFR CIGS/VSBYS ARE EXPECTED ALONG THE COAST THIS EVENING...THEN
WILL SPREAD INLAND TO THE CASCADES THROUGH 06Z...WITH HIGHER
TERRAIN BECOMING OBSCURED. THESE AREAS WILL CLEAR TO VFR BY
SATURDAY AFTERNOON. EAST OF THE CASCADES...VFR CONDITIONS WILL
PREVAIL THROUGH SATURDAY...BUT AREAS OF HIGHER TERRAIN WILL BECOME
OBSCURED AFTER 06Z TONIGHT. SPILDE
&&
.MARINE...UPDATED 230 PM PDT FRIDAY 20 MAR 2015...A COLD FRONT WITH
MODERATE WINDS AND HAZARDOUS SEAS WILL MOVE THROUGH THE WATERS THIS
EVENING WITH A SLIGHT CHANCE OF THUNDERSTORMS. WINDS AND SEAS WILL
GRADUALLY DIMINISH OVERNIGHT INTO SATURDAY NIGHT AS WEAK HIGH
PRESSURE BUILDS IN. ANOTHER COLD FRONT WILL MOVE ONSHORE SUNDAY
MORNING AND THIS WILL BRING ANOTHER ROUND OF SOUTH WINDS AND CHOPPY
SEAS SATURDAY NIGHT INTO SUNDAY. WINDS MAY APPROACH GALE FORCE
SUNDAY MORNING. A SERIES OF WEAKER DISTURBANCES WILL MOVE THROUGH
THE WATERS MONDAY AND TUESDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 PM PDT
THIS EVENING FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370-376.
$$
MAS/MAP/JRS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
208 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS INCREASED
QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS HIGHER FOR
LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING THE POSSIBLE
WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE EVENT...HIGHER
DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN THE INCREASED
QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL STRENGTH OF
THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE CONSALL QPF AND
ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER THAN 10/1 TRANSLATE
TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A LARGE PORTION OF
CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES THROUGH A PORTION OF
SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR AND MARGINAL SFC
TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON- PAVEMENT
SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW ACCUMS
WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS ON THE
RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE OVER THE GREAT LAKES WILL MIGRATE SEWD OVER CENTRAL
PA AIRSPACE TODAY BEFORE WEDGING EAST OF THE APPALACHIANS TONIGHT
INTO EARLY FRIDAY. THIS WILL ENSURE PREVAILING VFR CONDITIONS
THROUGH 3/4 OF THE PERIOD OR 00Z FRIDAY. SFC WINDS 290-330 DEC AOB
5KTS THROUGH THE AFTN THEN SHIFTING TO 090-150 FROM THIS EVENING
INTO TONIGHT. MOISTURE ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM
TRACKING INTO THE SRN MID-ATLC REGION WILL OVERRUN THE ESTABLISHED
COLD SECTOR AND RESULT IN WIDESPREAD MVFR TO IFR SNOW SPREADING SW
TO NE FROM APPROX 06-18Z FRI. TIMING MAY BE EARLIER IN THE SW AND
END A LITTLE LATER IN THE EAST. A RAIN/SNOW MIX IS STILL POSSIBLE
DURING THE AFTN OVER THE SE AIRFIELDS...BUT OVERALL THERMAL
PROFILES SUPPORT THE BULK OF THE PCPN AS SNOW. SNOW ENDS FROM W TO
EAST BY LATE FRI EVENING WITH LOW CIGS LKLY HOLDING INTO FRIDAY
NIGHT ESPECIALLY OVER THE WRN TAFS IN ZOB SECTOR. SOME LINGERING
DZ/FZDZ IS ALSO POSSIBLE INTO SATURDAY MORNING.
OUTLOOK...
SAT...MVFR/IFR -SHSN WEST...VFR CNTRL AND EAST. 20-25KT WIND GUSTS
FROM 270-300.
SUN-MON...NO SIG WX.
&&
.CLIMATE...
SPRING OFFICIALLY BEGINS AT 645 PM EDT ON MARCH 20 2015.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
202 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS INCREASED
QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS HIGHER FOR
LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING THE POSSIBLE
WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE EVENT...HIGHER
DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN THE INCREASED
QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL STRENGTH OF
THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE CONSALL QPF AND
ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER THAN 10/1 TRANSLATE
TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A LARGE PORTION OF
CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES THROUGH A PORTION OF
SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR AND MARGINAL SFC
TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON- PAVEMENT
SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW ACCUMS
WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS ON THE
RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE OVER THE GREAT LAKES WILL MIGRATE SEWD OVER CENTRAL
PA AIRSPACE TODAY BEFORE WEDGING EAST OF THE APPALACHIANS TONIGHT
INTO EARLY FRIDAY. THIS WILL ENSURE PREVAILING VFR CONDITIONS
THROUGH 3/4 OF THE PERIOD OR 00Z FRIDAY. SFC WINDS 290-330 DEC AOB
5KTS THROUGH THE AFTN THEN SHIFTING TO 090-150 FROM THIS EVENING
INTO TONIGHT. MOISTURE ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM
TRACKING INTO THE SRN MID-ATLC REGION WILL OVERRUN THE ESTABLISHED
COLD SECTOR AND RESULT IN WIDESPREAD MVFR TO IFR SNOW SPREADING SW
TO NE FROM APPROX 06-18Z FRI. TIMING MAY BE EARLIER IN THE SW AND
END A LITTLE LATER IN THE EAST. A RAIN/SNOW MIX IS STILL POSSIBLE
DURING THE AFTN OVER THE SE AIRFIELDS...BUT OVERALL THERMAL
PROFILES SUPPORT THE BULK OF THE PCPN AS SNOW. SNOW ENDS FROM W TO
EAST BY LATE FRI EVENING WITH LOW CIGS LKLY HOLDING INTO FRIDAY
NIGHT ESPECIALLY OVER THE WRN TAFS IN ZOB SECTOR. SOME LINGERING
DZ/FZDZ IS ALSO POSSIBLE INTO SATURDAY MORNING.
OUTLOOK...
SAT...MVFR/IFR -SHSN WEST...VFR CNTRL AND EAST. 20-25KT WIND GUSTS
FROM 270-300.
SUN-MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1233 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS
INCREASED QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS
HIGHER FOR LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING
THE POSSIBLE WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE
EVENT...HIGHER DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN
THE INCREASED QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL
STRENGTH OF THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE
CONSALL QPF AND ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER
THAN 10/1 TRANSLATE TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A
LARGE PORTION OF CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES
THROUGH A PORTION OF SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR
AND MARGINAL SFC TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON-
PAVEMENT SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW
ACCUMS WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS
ON THE RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
WINDS STILL UP A LITTLE HIGHER THAN I EXPECTED. WILL
MAKE SOME MINOR ADJUSTMENTS TO THE 03Z TAFS.
OVERALL WINDS WILL CONTINUE TO WEAKEN OVERNIGHT.
LOOKING AT VFR CONDITIONS THROUGH 00Z FRIDAY...WITH JUST SOME
HIGH CLDS.
CLOUDS WILL INCREASE FROM THE SOUTHWEST THURSDAY NIGHT...THEN
LOWER AND THICKEN UP LATE WITH SNOW SPREADING INTO THE SW ZONES
AROUND OR SHORTLY AFTER MIDNIGHT...AND LIKELY REACHING THE TAF
SITES /KBFD...KUNV AND KMDT/ BETWEEN 09-12Z FRIDAY.
MVFR TO IFR EXPECTED FOR MUCH OF FRIDAY IN PERIODS OF
SNOW...POSSIBLY MIXED WITH RAIN AT TIMES IN THE LOWER SUSQ VALLEY
DURING THE AFTERNOON HOURS.
EXPECT BULK OF THE PRECIPITATION TO BE IN THE FORM OF SNOW...AS
TEMPS AT 850 MB COOL DURING THE EVENT...AS LOW TRANSFERS TO THE
COAST. THIS MAKES SENSE...GIVEN HOW DRY THE AIRMASS IS...AND THAT
UPWARD MOTION WILL COOL THE AIRMASS.
MOST OF THE SNOW WILL BE EAST OF THE AREA BY 00Z SAT...EARLIER
ACROSS THE FAR WEST.
OUTLOOK...
THU NGT-FRI...MVFR/IFR LIKELY DEVELOPING IN SN ASSOCD WITH LOW
PRES TRACKING NE TO THE MID-ATLC/NORTHEAST COAST.
FRIDAY NIGHT...LINGERING DRIZZLE...FREEZING DRIZZLE OR LIGHT SNOW
EARLY AS LOW PRESSURE DEPARTS EAST OF THE MID ATL COAST WITH IFR
TO LIFR STRATUS CIGS/VSBYS...AND LIGHT/VARIABLE WIND.
SAT...MAINLY VFR...BUT MVFR/IFR PSBL NW IN -SHSN.
SUN-MON...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
410 AM CDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CDT THU MAR 19 2015
A WEAK TROUGH ACROSS THE FAR WESTERN DAKOTAS EARLY THIS MORNING WILL
SHIFT EAST THROUGH THE FORECAST AREA THIS AFTERNOON. EXPECT A FAIR
AMOUNT OF CLOUDS AHEAD OF THE BOUNDARY...BUT WILL GRADUALLY SHIFT
SOUTH AND EAST TOWARDS THIS EVENING. STILL COULD SEE SOME HIGH
CLOUDS TONIGHT ASSOCIATED WITH A WAVE PASSING TO THE
NORTH...OTHERWISE SHOULD SEE A CLEARING TREND BEHIND THE FRONT.
GUSTY WEST TO NORTHWEST WINDS ARE EXPECTED TO DEVELOP BEHIND THE
FRONT...AND WITH THE DRY FUELS ACROSS THE AREA WILL SEE A HIGH TO
VERY HIGH FIRE DANGER.
WITH MIXY CONDITIONS...WILL SEE HIGH TEMPS 10-15 DEGREES ABOVE
NORMAL IN THE 50S TO LOWER 60S. TONIGHT...DRY AND DECREASING
CLOUDS WILL ALLOW TEMPS TO FALL BACK INTO THE LOWER 30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM CDT THU MAR 19 2015
MAIN FOCUS FRIDAY THROUGH SATURDAY WILL BE WARM AND DRY CONDITIONS
ON FRIDAY AHEAD OF COLD FRONT...WHICH IS SET TO PUSH THROUGH THE
REGION LATE FRIDAY AND FRIDAY NIGHT. DEEP WEST-SOUTHWEST FLOW AHEAD
OF THE FRONT SHOULD RESULT IN STRONG MIXING OVER OUR DRY GROUND...
AND HAVE CONTINUED TO FAVOR WARMER END OF TEMPERATURE GUIDANCE WITH
HIGHS FROM THE LOWER 60S NORTHEAST...TO LOWER/MID 70S SOUTHWEST.
ALONG WITH THE WARM TEMPERATURES WILL BE MIXING DOWN OF DRIER DEW
POINTS...AND HAVE LOWERED AFTERNOON DEW POINTS INTO THE UPPER 20S TO
AROUND 30. THIS WILL RESULT IN MINIMUM RH LEVELS RANGING FROM NEAR
20 PERCENT IN SOUTH CENTRAL SD...TO NEAR 30 PERCENT IN SOUTHWEST MN
AND EAST CENTRAL SD. GFS/ECMWF/GEM NOW IN PRETTY GOOD AGREEMENT ON
FRONTAL TIMING...BRINGING THE BOUNDARY THROUGH THE NORTHWEST HALF OF
THE FORECAST AREA BY 00Z SATURDAY...THEN CONTINUING THROUGH THE
SOUTHEAST HALF DURING THE EVENING HOURS. THIS TIMING OF THE FRONT
SHOULD BRING A SLACKENED GRADIENT TO AREAS WITH THE MOST CRITICAL RH
VALUES DURING THE AFTERNOON...SO WHILE THESE CONDITIONS WILL BRING
AN ELEVATED FIRE DANGER TO MOST OF THE CWA...AT THIS TIME APPEARS
WIND SPEEDS WILL REMAIN BELOW CRITICAL LEVELS. FURTHER DETAIL CAN BE
FOUND IN THE FIRE WEATHER PORTION OF THIS DISCUSSION.
WINDS WILL SWING AROUND TO THE NORTHEAST LATE FRIDAY NIGHT INTO
SATURDAY. WILL SEE MORE LIMITED MIXING WITH THESE WINDS...BUT AMPLE
SUNSHINE AND DRY GROUND MAY OVERCOME THIS SOMEWHAT AND HAVE NUDGED
HIGHS UP JUST A BIT IN OUR NORTHEAST...WITH READINGS RANGING FROM
MID 40S NORTHEAST TO UPPER 50S THROUGH THE MISSOURI RIVER VALLEY.
GFS/ECMWF COMING INTO A LITTLE BETTER CONSENSUS ON EVOLUTION OF
SYSTEM SET TO AFFECT THE REGION EARLY NEXT WEEK. STRONG ISENTROPIC
LIFT AHEAD OF THE WAVE SATURDAY NIGHT/SUNDAY MORNING ACROSS MUCH OF
THE AREA...FOLLOWED BY A PERIOD OF WEAKER LIFT AND MID LEVEL DRYING
AS THE WAVE SLIDES SOUTHEAST ACROSS THE REGION. LACK OF MOISTURE
STILL A CONCERN TO START WITH...SO WILL HOLD POPS IN THE LOWER-MID
CHANCE RANGE... FOCUSING MORE ACROSS OUR NORTHEAST WHERE MOISTURE
PROFILES ARE A LITTLE MORE FAVORABLE. WITH LINGERING UNCERTAINTY IN
EXACT THERMAL PROFILES AT THIS RANGE...WILL STICK WITH GENERAL
RAIN/SNOW WORDING...WITH POTENTIAL FOR SOME ACCUMULATION ACROSS OUR
NORTHEAST FORECAST AREA. HOWEVER WILL HAVE TO MONITOR LATE SATURDAY
NIGHT/SUNDAY MORNING PERIOD FOR POSSIBLE WINTRY MIX AS TEMPERATURES
ALOFT CLIMB IN STRONG WARM ADVECTION WHILE LOW LEVEL NORTHEAST FLOW
DRAWS SOME COOLER AIR IN NEAR THE SURFACE.
GENERAL CONSENSUS MOVES THE PRECIP THREAT EAST OF THE AREA BY MIDDAY
MONDAY...BUT ANOTHER WAVE MOVES INTO THE NORTHERN PLAINS BY TUESDAY
AND BRINGS AN INCREASING PRECIP THREAT TUESDAY/TUESDAY NIGHT. LOOKS
TO BE WARM ENOUGH WITH THIS SYSTEM FOR PRIMARILY RAIN...WITH COLD
AIR MOVING IN BEHIND THE PRECIP THREAT. GFS/ECMWF BOTH SHOW A RIBBON
OF INSTABILITY AHEAD OF THE FRONT ON TUESDAY...BUT WITH DISAGREEMENT
IN TIMING OF THE WAVE/FRONT...HAVE LEFT THUNDER MENTION OUT OF THE
FORECAST FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1102 PM CDT WED MAR 18 2015
VFR CONDITIONS ARE EXPECTED TO REMAIN PREVAILING THROUGH THE TAF
PERIOD. THE EXCEPTION MAY BE SOME MVFR STRATUS LOCATED IN
NORTHERN KANSAS WHICH MAY SPREAD NORTHWARD INTO WEST CENTRAL IOWA
ONCE WINDS TURN SOUTHERLY LATE TONIGHT. MAIN CONCERN IS MAINLY
AROUND 12Z TO 16Z FOR THE KSUX TAF. THE NAM HAS BACKED AWAY FROM
THIS SOLUTION...HOWEVER THE HRRR CONTINUES TO SHOW SOME STRATUS
JUST SOUTH OF THE REGION. DECIDED TO REMOVE MENTION OF BROKEN
SKIES FROM THE KSUX TAF BUT WILL HAVE TO MONITOR THE PROGRESSION
OF THIS STRATUS LAYER OVERNIGHT.
&&
.FIRE WEATHER...
FRIDAY WILL BE A DAY OF ELEVATED FIRE DANGER OVER MUCH OF THE
REGION AS WARM AND DRY AIR MIX TO THE SURFACE AHEAD OF A COLD
FRONT. LOWEST RELATIVE HUMIDITY LEVELS EXPECTED TO REACH AROUND 20
PERCENT ACROSS THE LOWER BRULE AREA...EASTWARD THROUGH THE
MISSOURI RIVER VALLEY... RANGING UP TO AROUND 30 PERCENT FROM THE
MIDDLE BIG SIOUX VALLEY INTO SOUTHWEST MINNESOTA. AT THIS
TIME...APPEARS AS THOUGH LOCATIONS WITH THE LOWEST HUMIDITY LEVELS
WILL BE SPARED FROM THE STRONGEST WINDS...THOUGH THESE AREAS COULD
STILL SEE WINDS IN THE 15 TO 20 MPH RANGE WITH BRIEF GUSTS TO 25
MPH POSSIBLE. STRONGER WINDS FROM 20 TO 30 MPH ARE EXPECTED ACROSS
SOUTHWEST MINNESOTA AND THE IOWA GREAT LAKES...WHERE MINIMUM
HUMIDITY LEVELS WILL BE CLOSER TO 30 PERCENT. THUS WILL KEEP ALL
AREAS IN THE VERY HIGH FIRE DANGER CATEGORY FOR NOW...BUT
CONDITIONS WILL BE MONITORED CLOSELY OVER THE NEXT COUPLE OF DAYS
FOR CHANGES WHICH COULD RESULT IN FIRE WEATHER HEADLINES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...JH
AVIATION...
FIRE WEATHER...JH
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1021 PM CDT FRI MAR 20 2015
.DISCUSSION...MADE SOME CHANGES TO ACCOUNT FOR POSITIONING OF COLD
FRONT. RUC13 IS CAPTURING THE PROGRESSION OF THE FRONT BETTER THAN
MOST OTHER AVAILABLE GUIDANCE. BOUNDARY IS THROUGH THE NORTHERN
PART OF THE CWA. CONVECTION OVER THE VICTORIA CROSSROADS HAS MOVED
TO THE NORTHEAST...BUT RENEWED SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE OVERNIGHT. INGREDIENTS ARE STILL COMING
TOGETHER FOR A HEAVY RAIN EVENT OVER THE AREA TONIGHT INTO
SATURDAY MORNING. MOST LOCATIONS WILL RECEIVE BETWEEN 1 AND 3
INCHES OF RAIN...WITH SOME ISOLATED SPOTS OF 4 TO 6 INCHES. NO
CHANGES TO THE FLASH FLOOD WATCH ARE ANTICIPATED. LOCAL WEBCAMS
AND SURFACE OBS CONTINUE TO INDICATE DENSE FOG OVER THE NEARSHORE
WATERS AND BAYS SO WILL CONTINUE WITH DENSE FOG ADVISORY OVER
THESE AREAS.
&&
.PREV DISCUSSION... /ISSUED 645 PM CDT FRI MAR 20 2015/
DISCUSSION...BASED ON CURRENT RADAR TRENDS...STARTED THE ONSET OF
HIGHER POPS AROUND 23Z. NO CHANGES WERE MADE THOUGH TO THE FLASH
FLOOD WATCH AS HEAVY RAINFALL EVENT LOOKS LIKELY THIS EVENING AND
OVERNIGHT...ESPECIALLY OVER THE BRUSH COUNTRY AND RIO GRANDE
PLAINS. UPDATED AVIATION SECTION ATTACHED AS WELL.
AVIATION...POOR FLIGHT CONDITIONS ARE EXPECTED TO DEVELOP TONIGHT
AS LOW CLOUDS AND RAIN OVERSPREAD SOUTH TEXAS. VFR/MVFR CIGS
INITIALLY WILL TRANSITION TO IFR/LIFR THIS EVENING/OVERNIGHT AND
CONTINUE INTO SATURDAY. RAINFALL THREAT WILL INCREASE AS WELL AS
SLOWLY MOVING COLD FRONT INTERACTS WITH APPROACHING UPPER LEVEL
DISTURBANCE AND PLENTIFUL MOISTURE. A FEW THUNDERSTORMS WILL BE
POSSIBLE AS WELL. FOR THE MOST PART...PREVAILED SHRA AND INCLUDED
SOME VCTS REMARKS FOR ALL THE TERMINALS. FUTURE AMENDMENTS WILL
LIKELY BE NEEDED AND WILL UPDATE AS NECESSARY,
PREV DISCUSSION... /ISSUED 324 PM CDT FRI MAR 20 2015/
SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...MAIN FOCUS IN THE
SHORT TERM IS EXCESSIVE RAINFALL POTENTIAL ACROSS THE COASTAL BEND
WITH AN INCOMING FRONT TAPPING INTO BOTH PACIFIC AND GULF MOISTURE.
A SLOW MOVING UPPER LOW MOVING ACROSS NORTHERN MEXICO WILL AID IN
PACIFIC MOISTURE TRANSPORT...AND INFLOW INTO A WEAK COLD FRONT WILL
ADD GULF MOISTURE TO THE MIX TO CREATE VERY HIGH PRECIPITABLE WATER
TOTALS FOR THIS EVENT.
A PREFRONTAL TROUGH WILL TRACK ACROSS THE FORECAST AREA
OVERNIGHT...ACTING AS AN INITIAL AREA OF FOCUS. SCATTERED TO
NUMEROUS SHOWERS HAVE ALREADY DEVELOPED OVER PARTS OF THE AREA...AND
THAT ACTIVITY WILL INCREASE IN COVERAGE OVERNIGHT AS THE BOUNDARY
APPROACHES. THE BOUNDARY IS EXPECTED TO STALL OUT SOMEWHERE NEAR OR
JUST NORTH OF THE COASTAL BEND TOMORROW BEFORE FINALLY PUSHING
THROUGH SATURDAY NIGHT. BY THEN BEST FORCING AND MOISTURE WILL BE
MOVING EAST OF THE AREA...AND PRECIPITATION WILL BEGIN TO TAPER OFF.
NO SIGNIFICANT CHANGE IN EXPECTED RAINFALL TOTALS...WITH HIGHEST
AMOUNTS OVER THE WESTERN BRUSH COUNTRY AND LESSER AMOUNTS TOWARD THE
SOUTHEAST. WITH SATURATED GROUNDS ACROSS THE ENTIRE COASTAL
BEND...HOWEVER...ANY SIGNIFICANT RAINFALL ANYWHERE IN THE FORECAST
AREA WILL LIKELY CAUSE PONDING OF WATER AND LOCALIZED FLOODING. AS A
RESULT...A FLASH FLOOD WATCH IS IN EFFECT FROM THIS EVENING THROUGH
SATURDAY EVENING.
SEVERE THREAT FROM THIS SYSTEM...APART FROM FLOODING...APPEARS
MINIMAL. ISOLATED THUNDERSTORMS ARE POSSIBLE THROUGH THE EVENT...AND
SOME OF THESE MAY PRODUCE STRONG WIND GUSTS OR SMALL HAIL.
HIGH DEWPOINT AIR OVER THE RELATIVELY COOL NEARSHORE WATERS WILL
CONTINUE TO PRODUCE DENSE MARINE FOG OVERNIGHT...AND AN ADVISORY
REMAINS IN EFFECT AS VISIBILITIES WILL REMAIN COMMONLY LESS THAN A
MILE.
REDUCED DIURNAL TEMPERATURE RANGES SLIGHTLY FROM GUIDANCE BASED ON
COPIOUS MOISTURE LEVELS AND THICK CLOUD COVER.
LONG TERM (SUNDAY THROUGH FRIDAY)...MAIN FORECAST FOCUS HAS NOW
SHIFTED AWAY FROM THE LONG TERM...WITH THE HEAVY RAINFALL EVENT IN
THE SHORT TERM. BY SUNDAY MORNING UPPER LOW WILL HAVE LIFTED TO
NORTHEAST TEXAS. AN AREA OF ELEVATED MOISTURE STILL LINGERS ACROSS
THE GULF WATERS AND UP INTO THE VICTORIA CROSSROADS. BEFORE THE TAIL
END OF THE UPPER TROUGH SWINGS PAST AND DRIER AIR PUSHES INTO THE
REGION...COULD SEE A FEW ISOLATED THUNDERSTORMS LINGERING ACROSS
THESE AREAS IN THE MORNING....TAPERING OFF BY EARLY SUNDAY
AFTERNOON. THE MAJORITY OF THE LONG TERM WILL THEN REMAIN FAIRLY
TRANQUIL WITH ZONAL FLOW ALOFT...BRINGING MORE SUNSHINE AND WARMER
TEMPERATURES THROUGH THE MID WEEK. NEXT FORECAST CHALLENGE WILL BE
TIMING AND STRENGTH OF THE NEXT COLD FRONT LATE IN THE WEEK.
CONTINUE TO SEE DIFFERENCES IN MODELS AND RUNS WITH REGARD TO
TIMING...STRENGTH OF THIS FRONT...AND ANY PRECIP WITH IT. GFS BRINGS
DEEPER PLUME OF PACIFIC MOISTURE UP ACROSS THE REGION AGAIN...WHILE
THE ECMWF REMAINS SOMEWHAT DRIER ALOFT. CURRENT FORECAST TIMING HAS
FROPA OCCURRING THURSDAY EVENING INTO FRIDAY MORNING. TEMPERATURES
WILL BE COOLER ON THURSDAY BEFORE THE FRONT MOVES THROUGH
THOUGH...AS CLOUD COVER REALLY INCREASES AND CONVECTION DEVELOPS
AHEAD OF THE FRONT DURING THE DAY THURSDAY. FRIDAY WILL BE SEVERAL
DEGREES COOLER IN WAKE OF THIS COLD FRONT...AND WITH LINGERING
SHOWERS OVER THE AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 68 72 62 78 58 / 70 90 50 10 10
VICTORIA 63 71 61 77 55 / 90 100 70 20 10
LAREDO 66 73 61 79 58 / 100 80 30 10 10
ALICE 66 72 62 80 57 / 90 90 40 10 10
ROCKPORT 66 70 62 75 58 / 70 90 60 20 10
COTULLA 63 71 59 78 56 / 100 80 30 10 10
KINGSVILLE 67 73 62 79 58 / 70 90 50 10 10
NAVY CORPUS 66 71 63 75 59 / 70 90 60 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR THE FOLLOWING
ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...JIM
WELLS...KLEBERG...LA SALLE...LIVE OAK...MCMULLEN...NUECES...
REFUGIO...SAN PATRICIO...VICTORIA...WEBB.
GM...DENSE FOG ADVISORY UNTIL 4 AM CDT SATURDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...
BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR...
COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...
COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
OUT 20 NM.
&&
$$
TB/78...SHORT TERM
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
948 PM CDT FRI MAR 20 2015
.DISCUSSION...THE COMBINATION OF SURFACE OBS AND WEB CAM IMAGES
FROM SPI INDICATES THAT VSBYS ARE FALLING STEADILY DUE TO THE WAA
COMING IN FROM THE SE OVER FAIRLY COOLER SURF AND BAY WATER TEMPS
IN THE MID 60S. SO WILL POST UP A DENSE FOG ADVISORY FOR THE
LAGUNA MADRE...LOWER TX GULF WATERS OUT TO 20 NM OFFSHORE AND FOR
COASTAL WILLACY AND COASTAL CAMERON COUNTIES THROUGH 7 AM
TOMORROW.
CONCERNING THE MAIN SHORT TERM THREAT...HEAVY RAINFALL...THE SHORT
RANGE HRRR GUIDANCE MAINTAINS THE THREAT OF LOCALLY HEAVY RAINFALL
OVER PORTIONS OF THE NORTHERN AND WESTERN COUNTIES THROUGHOUT LATE
TONIGHT INTO SATURDAY MORNING. THE RAINFALL WILL EXPAND FURTHER
EAST AND SOUTH THROUGHOUT SATURDAY AS THE 500 MB CLOSED LOW TO OUR
WEST OPENS UP AND PUSHES EAST ACROSS TX SAT AND SAT NIGHT. SPC
MAINTAINS A MARGINAL THREAT FOR SVR T-STORMS THROUGHOUT SATURDAY
AS THE PWATS...CAPE VALUES AND BULK SHEAR INCREASE OVER THE
REGION. THE MAIN THREAT FROM ANY OF THE STRONGER CONVECTION THAT
FORMS WILL BE MAINLY FROM GUSTY WINDS AND POSSIBLE SEVERE HAIL.
FOR NOW WILL NOT MAKE ANY OTHER MAJOR CHANGES TO THE ONGOING
FORECAST WORDING. THE CURRENT FFA IN EFFECT MAY NEED TO BE
ADJUSTED OR POSSIBLY EXPANDED THROUGH THE OVERNIGHT HOURS TO
ACCOUNT FOR THE NEAR TERM CONV TRENDS OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 755 PM CDT FRI MAR 20 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...A FAIRLY COMPLEX AVIATION SITUATION IS SETTING UP
OVER THE NEXT 24 HOURS AS THE DEEP 500 MB TROUGH AXIS TO THE WEST
OF SOUTH TX DIGS EAST. THE APPROACH OF THIS TROUGH AXIS WILL
STEADILY DEEPEN THE PWAT AND CAPE VALUES THROUGHOUT TONIGHT AND
SATURDAY LIKELY RESULTING IN INCREASING CONV COVERAGE ACROSS THE
RGV AIPPORTS DURING THE LATTER HALF OF THE CURRENT TAF SETS AS THE
UPPER LEVEL SUPPORT INCREASES. THIS WILL RESULT IN PERIODS OF
VFR/MVFR CONDITIONS WITH PERIODS OF IFR CEILINGS/VSBYS DUE TO
PERIODS OF THE STRONGER CONV MAINLY AFTER 12Z SAT. IN THE EARLIER
TAF PERIODS EXPECT THE LOW LEVEL WAA MOVING OVER THE COOLER
NEARSHORE WATERS NEAR SPI TO ALLOW AREAS OF LOW CLOUDS AND VSBYS
TO REFORM AND ADVECT WESTWARDS LATER TONIGHT REUSLTING IN
IFR/LIFR CEILINGS FOR ALL THREE RGV AIRPORTS.
PREV DISCUSSION... /ISSUED 323 PM CDT FRI MAR 20 2015/
SHORT TERM /NOW THROUGH SATURDAY NIGHT/...LATEST WATER VAPOR
IMAGERY SHOWS A 500MB LOW OVER BAJA CALIFORNIA WITH ABUNDANT PACIFIC
MOISTURE STREAMING ACROSS THE AREA FROM THE SOUTHWEST. BRO RADAR
SHOWS SOME WEAK ECHOS ACROSS THE RIO GRANDE RIVER...SOUTH OF ZAPATA.
CURRENT SURFACE ANALYSIS SHOWS A WEAK COLD FRONT ACROSS THE HILL
COUNTRY THIS AFTERNOON. SURFACE OBSERVATIONS AND WEBCAMS ON SOUTH
PADRE ISLAND INDICATE LIGHT FOG/HAZE ALONG THE LOWER TEXAS...WITH
VISIBILITIES RANGING BETWEEN 5 TO 6 MILES. HOWEVER...THICKER SEA FOG
CONTINUES OVER THE NEAR SHORE GULF WATERS 0 TO 20 NM EAST OF PADRE
ISLAND.
TONIGHT...THE CUT OFF LOW WILL EJECT SLOWLY EAST INTO NORTHWEST
MEXICO. DEEP LAYERED SOUTHWEST FLOW WILL CONTINUE TO ADVECT GULF AND
PACIFIC MOISTURE THE REGION. THE WEAK COLD FRONT WILL SLOWLY MOVE
INTO THE RANCHLANDS LATER TONIGHT. THE WEAK SURFACE FRONT COMBINED
WITH ENERGY ALOFT WILL PROVIDE THE OPPORTUNITY FOR HEAVY RAIN...
ESPECIALLY ACROSS THE NORTHERN RANCHLANDS...FOR TONIGHT INTO
SATURDAY. THE LATEST WPC QPF VALUES PAINTS BETWEEN 1 TO 3
INCHES...LOCALLY UP TO 4 INCHES...ACROSS THE WESTERN PORTIONS OF
DEEP SOUTH TEXAS. DUE TO RECENT RAINS AND EXPECTED HEAVY RAINS...A
FLASH FLOOD WATCH HAS BEEN ISSUED FOR BROOKS...JIM HOGG AND ZAPATA
COUNTIES BEGINNING THIS EVENING AT 7 PM.
RAINFALL WILL INCREASE ACROSS THE WESTERN BRUSH COUNTRY INTO THE
UPPER VALLEY TONIGHT. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE ACROSS THE LOWER VALLEY..ESPECIALLY AFTER MIDNIGHT.
FOG WILL BE A CONCERN AGAIN TONIGHT ALONG THE COAST AND ACROSS THE
NEAR SHORE GULF WATERS TONIGHT DUE TO LIGHT WINDS AND HIGH
DEWPOINTS. AREAS OF FOG...LOCALLY DENSE FOG NEAR THE
COAST...EXPECTED TONIGHT. LOW TEMPERATURES TONIGHT WILL BE NEAR
NORMAL...IN THE MID 60S...UNDER CLOUDY SKIES.
SATURDAY AND SATURDAY NIGHT...THE 500MB LOW MOVES TOWARDS THE BIG
BEND REGION SATURDAY AND INTO NORTHERN TEXAS BY SATURDAY NIGHT.
SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS DEEP SOUTH TEXAS WITH
THE BEST LIFT OCCURRING SATURDAY INTO SATURDAY NIGHT. SPC SHOWS A
MARGINAL RISK OF SEVERE THUNDERSTORMS...GENERALLY ALONG AND EAST OF
I-69C/HWY 281 SATURDAY INTO SATURDAY NIGHT. THE MAIN IMPACTS WITH
THIS ACTIVITY WILL BE HEAVY RAIN...GUSTY WINDS AND SMALL HAIL...DIME
SIZE OR LESS. THE WEAK FRONT DRAPED ACROSS THE REGION SATURDAY NIGHT
WILL RESULT IN VERY LIGHT WINDS. THIS WILL RESULT IN AREAS OF
FOG...SOME LOCALLY DENSE...ALONG THE COAST. HIGH TEMPERATURES
SATURDAY WILL BE IN THE 70S WITH UPPER 60S ALONG THE COAST.
OVERNIGHT LOW TEMPERATURES SATURDAY NIGHT WILL BE IN THE UPPER 50S
ACROSS THE RANCHLANDS TO THE MID 60S NEAR THE COAST.
LONG TERM /SUNDAY THROUGH FRIDAY/...DRIER AIR WILL MOVE INTO
SOUTHWEST TEXAS SUNDAY BRINGING AN END TO THE RAIN CHANCES ACROSS
THE CWA AS THE 500MB SHORTWAVE TROUGH ACROSS TEXAS MOVES EASTWARD
AND THE SOUTHWEST FLOW ALOFT VEERS TO THE WEST AND NORTHWEST
PROVIDING SUBSIDENCE ACROSS THE WESTERN HALF OF THE STATE. AT THE
SURFACE...THE WEAK COLD FRONT WILL MOVE THROUGH THE RIO GRANDE
VALLEY SUN AFTERNOON. WARM AND RELATIVELY DRY CONDITIONS SHOULD
PREVAIL ACROSS SOUTH TX MONDAY THROUGH WEDNESDAY WITH A NEARLY
ZONAL FLOW PREVAILING ACROSS THE SOUTHERN UNITED STATES. A 500MB
TROUGH IS EXPECTED TO DEVELOP ACROSS THE CENTRAL U.S. AND A 500MB
TROUGH/LOW IS ALSO EXPECTED TO DEVELOP ACROSS BAJA CALIFORNIA
WEDNESDAY INTO THURSDAY. LOW TO MID LEVEL MOISTURE IS PROGGED TO
INCREASE ACROSS SOUTH TX WEDNESDAY AND THURSDAY BEFORE A COLD
FRONT MOVES THROUGH THE RIO GRANDE VALLEY THURS NIGHT INTO FRI
MORNING. THERE ARE STILL SOME DIFFERENCES BETWEEN THE ECMWF AND
THE GFS ON THE TIMING OF THIS FRONT. WILL MENTION A SLIGHT CHANCE
TO CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY AND A CHANCE OF
SHOWERS FRIDAY AS MOISTURE POOLS ALONG AND AHEAD OF THE FRONT
THROUGH THE REST OF THE FORECAST PERIOD.
MARINE...
NOW THROUGH SATURDAY NIGHT...SHOWERS AND THUNDERSTORMS POSSIBLE
SATURDAY AND SATURDAY NIGHT AS A WEAK COLD FRONT APPROACHES THE
LOWER TEXAS COASTAL WATERS. LIGHT TO MODERATE SOUTHEAST WINDS AND
LOW SEAS WILL PREVAIL THROUGH THE FORECAST PERIOD.
SUNDAY THROUGH WEDNESDAY...LIGHT SOUTH WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS SUNDAY BEFORE A WEAK COLD FRONT MOVES OFFSHORE
THE LOWER TEXAS COAST SUN AFTERNOON. WINDS WILL SHIFT TO THE
NORTHWEST SUN AFTERNOON BUT BECOME LIGHT AND VARIABLE SUN NIGHT.
THE WINDS WILL INCREASE FROM THE NORTH AS HIGH PRESSURE FINALLY
BUILDS INTO THE WESTERN GULF OF MEXICO MONDAY IN THE WAKE OF THE
FRONTAL SYSTEM OVER EAST TX SUNDAY MOVING EASTWARD MONDAY. LIGHT
TO MODERATE NORTH WINDS MONDAY WILL VEER TO THE SOUTHEAST TUESDAY
AS THE SURFACE RIDGE MOVES QUICKLY EASTWARD. LIGHT TO MODERATE
SOUTHEAST WINDS SHOULD PREVAIL ACROSS THE LOWER TX COAST TUESDAY
INTO WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 68 74 63 80 / 30 50 60 20
BROWNSVILLE 68 76 63 82 / 30 50 60 20
HARLINGEN 68 76 63 84 / 40 60 60 20
MCALLEN 68 75 62 86 / 50 70 50 20
RIO GRANDE CITY 67 72 60 83 / 70 70 40 10
SOUTH PADRE ISLAND 67 69 63 76 / 30 40 60 20
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR TXZ248>250.
DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR TXZ256-257.
GM...DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR GMZ130-132-135-
150-155.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM...60
LONG TERM...67
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
403 AM MDT THU MAR 19 2015
.SYNOPSIS...
SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE TODAY THROUGH SATURDAY
AS AN UPPER LOW SOUTHWEST OF ARIZONA SLIDES ACROSS NORTHERN MEXICO
AND TO THE BIG BEND REGION SATURDAY. TEMPERATURES WILL REMAIN NEAR
NORMAL. DRIER WEST FLOW DEVELOPS LATER SATURDAY AND LASTS THROUGH
MID WEEK OF NEXT WEEK. THIS WILL KEEP SKIES MOSTLY CLEAR AND
TEMPERATURES WILL CLIMB TO WELL ABOVE NORMAL. AFTERNOONS WILL BE
BREEZY ON TUESDAY AND WEDNESDAY.
&&
.DISCUSSION...
UPPER LOW NOW JUST WEST OF THE NORTHERN BAJA WITH SOME SUBTROPICAL
MOISTURE STREAMING AHEAD OF THE LOW OVER MOST OF ARIZONA AND NEW
MEXICO. RADAR SHOWS WESTERN CWA (LUNA COUNTY WEST) FILLING IN WITH
SHOWERS. HI-RES MODELS SHOWING A FAVORED AREA OF THE CWA TODAY WEST
OF EL PASO. LATEST HRRR SHOWING DECENT QPF DEMING WEST THIS MORNING
WITH RAINFALL AMOUNTS APPROACHING ONE-HALF INCH. NAM 12 ALSO HITS
THE BOOTHEEL AND GILA HARD WITH RAIN TODAY. POPS IN GRIDS DEFINITELY
SHOW THIS FAVORING...THOUGH KEEP LOW POPS IN FOR THE REST OF THE
AREA. SHOWERS TO CONTINUE TONIGHT THOUGH LESS COVERAGE EXPECTED.
MODELS SHOW WEAK BACK DOOR COLD FRONT MOVING IN LATE TONIGHT/EARLY
FRIDAY MORNING...PROBABLY ONLY MAKING IT AS FAR WEST AS THE RIO
GRANDE VALLEY. THIS COULD BE A FOCUS FOR SHOWERS FRIDAY...BUT MODELS
MOSTLY BEARISH (NAM/ECMWF) ON RAINFALL FRIDAY. BOTH THESE MODELS
SHOW DRY SLOTTING AND RAINFALL BECOMING QUITE SPOTTY. GFS STILL MORE
BULLISH WITH NOT MUCH SIGN OF ANY DRY SLOTTING.
BY SATURDAY MORNING THE UPPER LOW IS JUST WEST OF THE BIG BEND AND
WESTERN PARTS OF THE CWA SHOULD BEGIN CLEARING. STILL SLIGHT CHANCE
OF SHOWERS EL PASO EAST WHERE MOISTURE IS STILL AVAILABLE...BUT THIS
SHOULD MOVE EAST OUT OF THE AREA BY SATURDAY AFTERNOON.
REST OF FORECAST PERIOD RESEMBLES A MORE TYPICAL MARCH AS DRY
WESTERLIES DEVELOP BEHIND THE EXITING LOW. TEMPERATURES SHOULD CLIMB
SMARTLY WITH THIS DRIER FLOW...WITH MANY LOWLAND AREAS REACHING 80+
DEGREES BY TUESDAY. AFTERNOONS WILL BECOME BREEZY TUESDAY AND
WEDNESDAY.
&&
.AVIATION...VALID 19/12Z-20/12Z...
VFR GENERALLY THROUGH PERIOD...WITH SKIES SCT/BKN120 LAYERS TO 300.
SCATTERED -SHRA BKN080...MOSTLY FREQUENT WEST OF EL PASO. FOR THE
MORNING HOURS THROUGH ABT 15Z...FEW AREAS OF VSBY LESS THAN ONE MILE
IN FOG. AFT 18Z...A FEW THUNDERSTORMS POSSIBLE. WIND GUSTS OF 25-35
KTS POSSIBLE WITH THESE STORM.
&&
.FIRE WEATHER...
AN UPPER LOW CURRENTLY MOVING INTO THE BAJA REGION WILL PROGRESS
VERY SLOWLY EASTWARD THROUGH SATURDAY. THIS WILL KEEP A CHANCE FOR
SHOWERS AND THUNDERSTORMS OVER THE FORECAST AREA. DECENT LOW LEVEL
MOISTURE WILL REMAIN IN PLACE KEEPING RELATIVE HUMIDITIES ABOVE 20
PERCENT. AS THE UPPER LOW EXITS TO THE EAST...ZONAL FLOW WILL SETUP
WITH OCCASIONAL BREEZY TO WINDY CONDITIONS BY TUESDAY AND
WEDNESDAY...BUT AT THIS TIME LOOKING TO REMAIN BELOW RED FLAG WIND
CRITERIA. TEMPERATURES WILL ALSO BE ON THE INCREASE WITH HIGHS
POSSIBLY TOPPING 80 DEGREES FOR THE FIRST TIME THIS YEAR OVER THE
LOWLANDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 70 51 71 49 73 / 20 20 20 20 20
SIERRA BLANCA 69 49 66 47 68 / 20 20 20 30 40
LAS CRUCES 69 47 70 45 72 / 30 20 20 20 20
ALAMOGORDO 70 47 69 43 72 / 30 30 30 20 30
CLOUDCROFT 47 34 49 35 53 / 40 40 40 30 30
TRUTH OR CONSEQUENCES 66 46 67 43 70 / 40 30 30 20 20
SILVER CITY 56 44 59 42 64 / 50 30 40 30 20
DEMING 69 45 70 44 73 / 40 20 30 20 20
LORDSBURG 66 44 69 42 71 / 40 30 30 20 10
WEST EL PASO METRO 70 52 71 51 73 / 20 20 20 20 20
DELL CITY 72 44 68 43 71 / 20 20 20 20 40
FORT HANCOCK 72 50 71 48 72 / 20 20 20 20 40
LOMA LINDA 66 50 66 48 66 / 20 20 20 20 30
FABENS 70 49 71 47 73 / 20 20 20 20 30
SANTA TERESA 70 49 70 48 72 / 20 20 20 20 20
WHITE SANDS HQ 68 50 68 48 71 / 20 20 20 20 20
JORNADA RANGE 70 44 70 42 72 / 30 30 30 20 20
HATCH 69 46 69 44 73 / 30 30 30 20 10
COLUMBUS 67 49 69 47 71 / 40 20 20 20 10
OROGRANDE 69 50 68 47 71 / 20 20 20 20 30
MAYHILL 57 36 55 36 60 / 30 30 40 30 30
MESCALERO 57 35 57 36 60 / 40 40 40 30 30
TIMBERON 56 38 56 38 59 / 30 30 40 20 30
WINSTON 57 39 58 39 64 / 50 30 40 30 30
HILLSBORO 65 46 64 44 66 / 40 30 30 30 20
SPACEPORT 69 42 69 41 72 / 40 30 30 20 20
LAKE ROBERTS 58 39 61 37 64 / 60 30 50 30 30
HURLEY 59 43 61 42 66 / 40 30 30 30 20
CLIFF 65 42 67 40 71 / 50 30 40 30 20
MULE CREEK 63 40 65 38 68 / 50 30 40 30 20
FAYWOOD 64 45 64 44 66 / 40 30 30 30 20
ANIMAS 67 46 69 45 73 / 40 30 30 20 10
HACHITA 68 45 70 43 72 / 40 30 30 20 10
ANTELOPE WELLS 67 44 70 43 72 / 40 30 30 20 10
CLOVERDALE 65 46 67 44 68 / 50 30 30 20 10
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
17 HEFNER
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
644 PM EDT THU MAR 19 2015
.SYNOPSIS...
ONE LOW PRESSURE SYSTEM WILL CROSS TO THE COAST FROM THE TENNESSEE VALLEY
AND THEN HEAD NORTH ALONG THE COAST FRIDAY. A SECOND LOW WILL HEAD
EASTWARD ALONG THE OHIO VALLEY ON FRIDAY WITH ITS ASSOCIATED COLD
FRONT SWEEPING ACROSS THE AREA. HIGH PRESSURE WILL BUILDS INTO THE
AREA FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 630 PM EDT THURSDAY...
MADE SOME ADJUSTMENTS TO POPS/WX TYPE/TEMPS AND SNOW AMOUNTS
THROUGH EVENING. HRRR FROM 21Z SEEMS TO BE HANDLING LOCATION OF
PRECIP FAIRLY WELL. STILL GETTING A MIX OF SLEET/RAIN HERE WITH
SNOW FURTHER NORTH INTO THE HIGHER ELEVATIONS. MADE ADJUSTMENTS TO
THE PTYPE BASED ON THE RAP AND WET BULB...WHICH GIVES MORE SNOW TO
THE HIGHER ELEVATIONS NORTH OF LWB AND LEXINGTON. SOME AREAS COULD
SEE AN INCH OR TWO OF SNOW...BUT OVERALL THE SNOW AMOUNTS WILL BE
LIMITED BY WET/MILD GROUND. MOST LOCATIONS WILL HAVE MAINLY RAIN
OVERNIGHT...WITH SOME PERIODS WHERE NOTHING IS FALLING FROM THE
SKY BETWEEN UPPER VORTS. THERE IS A TIGHT GRADIENT IN TERMS OF
DEWPOINTS IN THE NORTH...WHERE CHO/SHD HAVE DEWPOINTS IN THE 20S
WHERE PRECIP HAS HELD OFF TO MID 30S AROUND LYH...SO THERE WILL
BE WET-BULBING EFFECTS NORTH OF INTERSTATE 64 INTO THE BLUE RIDGE
NORTH OF ROANOKE WHERE SNOW AND SLEET OCCUR EARLY.
ROADS SHOULD STAY WET GIVEN MILD TEMPERATURES OF THE
GROUND...THOUGH OVER THE HIGHER SECONDARY ROADS OF GREENBRIER
COUNTY EAST TO ROCKBRIDGE...A COATING MAY OCCUR.
PREVIOUS VALID DISCUSSION...
LOW PRESSURE WAS PROGRESSING INTO EASTERN TENNESSEE ALL WHILE A
PRECIPITATION ASSOCIATED WITH ITS WARM CONVEYOR BELT SPREAD ACROSS
THE REGION.
THROUGH THE OVERNIGHT...BOTH TEMPERATURES AND DEW POINTS WILL SLOWLY
RISE SO THAT LOW TEMPERATURES SHOULD OCCUR AROUND SUNSET...EXCEPT
FOR THOSE AREAS IN THE NORTH THAT WILL START TO COOL AS THE
PRECIPITATION INCREASES IN INTENSITY. LOWS WILL RANGE FROM THE
LOW TO MID 30S ACROSS THE MOUNTAINS TO THE UPPER 30S TO LOWER 40S
ACROSS THE PIEDMONT.
BY FRIDAY MORNING...THE TENNESSEE LOW WILL BE NEAR THE
COAST...AND STARTED ITS PROGRESSION NORTHEAST.
CONCURRENTLY...ANOTHER AREA OF LOW PRESSURE WILL BE PROGRESSING
EASTWARD THROUGH THE OHIO VALLEY. ITS ASSOCIATED COLD FRONT WILL
PROGRESS ACROSS THE AREA FRIDAY AFTERNOON. UNTIL THAT
TIME...EXPECT THE COLD AIR DAMMING WEDGE TO HOLD FAST ACROSS THE
REGION...WITH PLENTY OF CLOUD COVER. PRECIPITATION WILL GRADUALLY
DECREASE IN COVERAGE ACROSS THE AREA FRIDAY MORNING WITH THE
DEPARTURE OF THE COASTAL LOW. HOWEVER...LOOK FOR A RESURGENCE IN
THE WEST AS THE COLD FRONT CROSSES THE AREA. FRIDAY
AFTERNOON...PRECIPITATION IS EXPECTED TO BE LACKING EAST OF THE
BLUE RIDGE AS DOWNSLOPE WINDS SUPPRESS THE ACTIVITY. TEMPERATURES
WILL BE SLOW TO RISE WHILE THE COLD AIR DAMMING IS STILL IN PLACE.
IRONICALLY...IT WILL TAKE THE COLD FRONT TO HELP MIX THE LOWER
ATMOSPHERE AND START TO THIN OUT THE CLOUD COVER A BIT IN THE EAST
TO HELP TEMPERATURES RISE ON FRIDAY. HIGHS ARE EXPECTED TO RANGE
FROM THE UPPER 40S TO AROUND 50 ACROSS THE MOUNTAINS...TO THE 50S
ACROSS THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 310 PM EDT THURSDAY...
CONFLUENT FLOW ALOFT AND DRIER AIR BEHIND THE COLD FRONT FRIDAY AND
SATURDAY. ANY PRECIPITATION THAT IS LEFT OVER LATE IN THE DAY ON
FRIDAY WILL QUICKLY DISSIPATE FRIDAY EVENING.
A COLD FRONT WILL COME THROUGH SATURDAY. NO PRECIPITATION IS
EXPECTED ALONG THIS BOUNDARY.
HAVE PROBABILITY OF PRECIPITATION MOVING BACK INTO THE SOUTHERN
COUNTY WARNING AREA ON SUNDAY WITH THE APPROACH OF A WEAKENING
SOUTHERN STREAM SHORT WAVE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 1205 PM EDT THURSDAY...
SPLIT FLOW WITH BROAD EASTERN UNITED STATES TROF ON MONDAY
TRANSITIONS TO A WESTERN TROF AND RIDGING OVER THE EAST ON WEDNESDAY
AND THURSDAY. SOUTHERN STREAM SYSTEM REMAINS SUPPRESSED ON SUNDAY
NIGHT AND MONDAY WITH A MAJORITY OF THE HEAVIER PRECIPITATION ACROSS
THE SOUTHEAST UNITED STATES. SOME WINTER PRECIPITATION MAY BE
POSSIBLE ON THE NORTHERN FRINGE OF THIS SYSTEM. THIS WILL DEPEND ON
HOW FAR COLDER AIR AND HIGH PRESSURE WEDGES DOWN INTO THE MID
ATLANTIC REGION. CENTER OF HIGH PRESSURE WILL BE IN A FAVORABLE
POSITION FOR A WEDGE ON MONDAY. CAD WILL ALSO BE ENHANCED BY INVERTED
TROFFING WEST OF THE APPALACHIANS.
SOME SHORT WAVE ENERGY COMING THROUGH THE NORTHERN STREAM ON TUESDAY
MAY IMPACT THE FORECAST AREA. THERE WILL ALSO BE A WARMING TREND ON
WEDNESDAY AND THURSDAY IN ADVANCE OF THE NEXT SIGNIFICANT COLD
FRONT. ECMWF SHOWED SOME INDICATIONS OF A CHANCE OF PRECIPITATION IN
ASSOCIATION WITH A WARM FRONT ON WEDNESDAY. SURFACE HIGH PRESSURE
MOVES OFFSHORE BY WEDNESDAY WITH DEEP MOISTURE COMING OUT OF THE
GULF AHEAD OF THE COLD FRONT.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 145 PM EDT THURSDAY...
PRECIPITATION SHIELD OF RAIN AND SNOW CONTINUES TO SPREAD ACROSS
THE AREA. ISOLATED SLEET HAS BEEN NOTED NEAR THE VA/NC BORDER.
CIGS WILL CONTINUE TO TREND TO MVFR LEVELS AS THE AFTERNOON
PROGRESSES ALONG WITH MVFR/VFR VSBYS IN ASSOCIATION WITH THE
PRECIPITATION. PRECIPITATION WILL INCREASE THROUGH THE NIGHT WITH
A TREND TOWARDS MORE RAIN THAN SNOW...ALTHOUGH SNOW WILL STILL BE
POSSIBLE AT HIGHER ELEVATIONS...ESPECIALLY ALONG AND NORTH OF I-64.
CIGS AND VSBYS WILL TREND LOWER WITH MANY LOCATIONS WITH IFR CIGS
AND VSBYS BY 12Z/8AM FRIDAY.
THERE WILL BE A DECREASE IN THE PRECIPITATION COVERAGE FRIDAY
MORNING AS A COASTAL LOW LIFTS NORTHEAST AWAY FROM THE AREA.
HOWEVER...ANOTHER LOW MOVING THROUGH THE OHIO VALLEY WILL BRING
ITS ASSOCIATED PRECIPITATION TOWARDS THE REGION BY MID-DAY
FRIDAY. ANTICIPATE AREAS ALONG AND EAST OF THE BLUE RIDGE TO TREND
TO LOW END VFR. MVFR CONDITIONS WILL BE MORE COMMON ACROSS THE
MOUNTAINS.
EXTENDED FORECAST...COLD FRONT MOVES THROUGH THE REGION ON FRIDAY
IMPROVING CONDITIONS TO VFR AT ROA/LYH/DAN. CLOUDS MAY LINGER IN
THE MOUNTAINS...IMPACTING BLF/LWB/BCB...WITH POTENTIAL FOR MVFR
THROUGH MUCH OF FRIDAY. HIGH PRESSURE AND RETURN TO MAINLY VFR
CONDITIONS EXPECTED FOR THE WEEKEND AND EARLY NEXT WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS PADUCAH KY
320 AM CDT SAT MAR 21 2015
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 320 AM CDT SAT MAR 21 2015
HIGH CLOUDS ARE STREAMING NORTHEAST ACROSS THE ENTIRE REGION
THIS MORNING..AND THAT IS LIKELY TO CONTINUE THROUGH THE DAY
TODAY. NOT SURE HOW MUCH IMPACT IT WILL HAVE ON TEMPERATURES...BUT
ESPECIALLY IN THE SOUTH WOULD NOT BE SURPRISED IF IT HELD READINGS
DOWN A FEW DEGREES. IN THE NORTH...THE 00Z MODELS ALL BRING A WEAK
COLD FRONTAL WIND SHIFT INTO THE REGION...AND THAT COULD ALSO
PRESUMABLY KNOCK TEMPERATURES DOWN A FEW DEGREES FROM PREVIOUS
FORECASTS. THE OZARK FOOTHILLS REGION WILL STILL SEE TEMPERATURES
AROUND 70...BUT ELSEWHERE KNOCKED HIGHS DOWN A FEW DEGREES CLOSER
TO THE CONSENSUS OF 00Z GUIDANCE.
THE 00Z MODELS CONTINUE TO OPEN UP AND PUSH THE BAJA UPPER LOW
EAST NORTHEASTWARD INTO THE MID-SOUTH BY 00Z MONDAY. THE 03Z
SREF...00Z CANADIAN...AND 00Z WRF ARW AND NMM MODELS ALL BRING
THE NORTHERN EDGE OF THE PRECIPITATION SHIELD RIGHT TO THE
SOUTHERN BORDER OF OUR AREA. INCREASED POPS TO NEAR 15 RIGHT ON
THE AR AND TN BORDERS...BUT KEPT OUR REGION DRY FOR LATE TONIGHT
THROUGH SUNDAY AND INTO SUNDAY EVENING. IT WILL NOT BE A SURPRISE
TO SEE SOME LIGHT RAIN EVENTUALLY GET INTO SOUTHEAST MISSOURI OR
WEST KENTUCKY IN THIS TIME FRAME...BUT THE EVIDENCE IS JUST NOT
GREAT ENOUGH TO WARRANT A POP AT THIS TIME.
AS THAT SYSTEM PUSHES FARTHER EAST...A DISTURBANCE IN THE
NORTHWEST FLOW ALOFT MAY ALLOW A FEW SHOWERS TO PUSH INTO
NORTHWEST PORTIONS OF THE AREA MONDAY. THIS SYSTEM IS LOSING ITS
SURFACE REFLECTION OVER THE PLAINS AND ANY SHOWERS THAT TRY TO
REACH OUR AREA WOULD LIKELY BE DRYING UP QUICKLY AND AMOUNT TO
NEXT TO NOTHING. DID INSERT A SLIVER OF A SLIGHT CHANCE ALONG I-64
IN SOUTHERN ILLINOIS JUST TO BE SAFE.
A STRONGER UPPER-LEVEL STORM SYSTEM WILL PUSH EASTWARD INTO THE
NORTHERN PLAINS BY 12Z TUESDAY. THE 00Z MODELS ARE IN AGREEMENT IN
PUSHING A WARM FRONT NORTHWARD INTO OUR REGION...AND DEVELOPING
SLIGHTLY NEGATIVE SHOWALTER INDICES ALONG AND NORTH OF IT
OVERNIGHT. A FEW ELEVATED SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE MAINLY OVER SOUTHERN ILLINOIS OVERNIGHT MONDAY NIGHT INTO
TUESDAY MORNING. SLIGHT CHANCE POPS SHOULD SUFFICE FOR NOW.
WITH PLENTY OF AT LEAST HIGH CLOUD COVER... AND SURFACE HIGH
PRESSURE BUILDING INTO THE REGION FROM LATE THIS AFTERNOON THROUGH
MONDAY...TEMPERATURES ARE TRENDING SLIGHT DOWNWARD FROM PREVIOUS
FORECASTS. AFTER HIGHS ABOVE NORMAL IN THE UPPER 60S TODAY...A
COOLING TREND IS EXPECTED THROUGH MONDAY. THIS WILL STILL KEEP
READINGS AT OR ABOVE NORMAL EACH AFTERNOON. LOWS WILL ALSO BE AT
OR ABOVE NORMAL THROUGH THE PERIOD. MONDAY NIGHT COULD BE QUITE
MILD WITH THE WARM FRONT AND PRESUMABLY QUITE A BIT CLOUD COVER.
.LONG TERM...(TUESDAY THROUGH SATURDAY NIGHT)
ISSUED AT 320 AM CDT SAT MAR 21 2015
THIS EXTENDED FORECAST PERIOD STARTS WITH THE BEGINNING INFLUENCE OF
A DEVELOPING AND NEGATIVELY TILTED SHORTWAVE MOVING LEE OF THE
ROCKIES INTO THE UPPER MIDWEST AND THE CENTRAL PLAINS. THE
DIFFERENTIAL VORTICITY FIELDS AND INCREASING MOISTURE ADVECTION FROM
THE GULF OF MEXICO SERVES TO ACTIVATE (LIGHT UP) THE BAROCLINIC ZONE
(ENHANCED WARM FRONTAL ZONE) ORIENTED ACROSS THE NORTHERN HALF OF
THE WFO PAH FORECAST AREA.
RECENT MODEL TRENDS THE LAST 24-48 HOURS INDICATE THAT A TRAIN OF
ENERGY (SHORTWAVES) FOLLOWING THE LEAD SHORTWAVE SERVE TO
DEEPEN/SLOW DOWN THE TROUGH WEDNESDAY AFTERNOON THROUGH THURSDAY
EVENING. THIS ENHANCES COLD AIR ADVECTION FROM THE UPPER MIDWEST,
TIGHTENING THE BAROCLINIC ZONE AND INCREASING FRONTOGENESIS OVER THE
MIDDLE AND UPPER MISSISSIPPI VALLEY WEDNESDAY AFTERNOON.
FOR WHAT SEEMS TO BE THE STORY OF THE WINTER SEASON, SOME OF THE
ENERGY IN THE NORTHERN U.S. DIVES DOWN TOWARD CALIFORNIA/NORTHERN
MEXICO, GENERATING A CLOSED LOW CIRCULATION. AS PREVIOUSLY MENTIONED
IN OTHER DISCUSSIONS, THIS LOW SERVES TO AID IN HEIGHT FALLS
UPSTREAM, ENHANCING AND SHARPENING THE TROUGH IN THE CENTRAL PLAINS
AS THE UPPER LOW SHEARS OUT OVER THE NORTHEAST U.S. THIS IN TURN
SLOWS THE OVERALL EXIT OF THE COLD FRONT THROUGH THE WFO PAH
FORECAST AREA AND LEADS TO MINOR-OVERRUNNING OF MOISTURE OVER THE
POST FRONTAL ZONE. THIS WILL KEEP A SMALL CHANCE FOR RAIN OVER THE
AREA THROUGH AT LEAST FRIDAY.
NUMERICAL MODEL SIGNALS STILL SUGGEST THAT THE STRONGEST FORCING,
HIGHEST PRECIPITABLE WATER VALUES, HIGHEST POPS WILL BE FOCUSED ON
WEDNESDAY AFTERNOON AND EVENING. THE GREATEST CONVECTIVE POTENTIAL
STILL LIES JUST BEFORE AND DURING THAT TIME PERIOD. A FURTHER
ASSESSMENT FOR ANY SEVERE OR NEAR SEVERE POTENTIAL WILL BE ADDRESSED
IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.AVIATION...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
CONSIDERABLE HIGH CLOUDS OVERNIGHT. WINDS NOT ENTIRELY CALM
THROUGH 06Z. GUIDANCE SUGGESTS CALM BUT THE RAP 13KM SAYS IT MAY
NOT STAY THAT WAY (2-3 KTS AT TIMES). GIVEN BOTH FACTORS...WILL
LIMIT THE FOG MENTION. HIGH CLOUDS WILL PERSIST THROUGH SATURDAY
AS WELL WITH LIGHT WINDS CONTINUING...MAINLY WITH A SSW COMPONENT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...SMITH
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 150 AM EDT SAT MAR 21 2015
QUICK UPDATE TO FRESHEN UP GRIDS WITH LATEST OBS AND TRENDS. DID
PUT DRIZZLE IN A BIT LONGER MAINLY ACROSS THE EAST AS RADAR
CONTINUES TO SHOW SOME LIGHTER RETURNS. OTHERWISE NO MAJOR
CHANGES NEEDED FOR THIS UPDATE.
UPDATE ISSUED AT 1105 PM EDT FRI MAR 20 2015
HOURLY GRIDS WERE UPDATED BASED ON RECENT RADAR AND OBSERVATION
TRENDS. AREAS OF DRIZZLE CONTINUE ACROSS THE RADAR PER OBS AND
RADAR IMAGERY GENERALLY SOUTH OF INTERSTATE 64 AND EAST OF
INTERSTATE 75. THIS SHOULD GRADUALLY DIMINISH AS THE MOISTURE
BECOMES SHALLOWER. PATCHY FOG IS STILL ANTICIPATED AND MAY BE
DENSE AT TIMES ON SOME RIDGES. CLOUDS SHOULD NOT SCATTER OUT UNTIL
AROUND DAYBREAK...EXCEPT PERHAPS IN THE FAR NORTHWEST.
UPDATE ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 125 AM EDT SAT MAR 21 2015
LOW CLOUDS AND DRIZZLE STILL HANGING IN AT MANY SITES TONIGHT.
AREAS OF DRIZZLE ARE EXPECTED TO CONTINUE TO SUBSIDE OVERNIGHT AS
DRIER AIR SLOWLY WORKS EAST. MOST SITES WILL STAY IFR OR MVFR
THROUGH MID MORNING AT THE LATEST BEFORE WE BEGIN TO SEE SKIES
SCATTER OUT FROM WEST TO EAST. VFR CONDITIONS RETURN FOR MUCH OF
THE END OF THE TAF PERIOD AS DRYER AIR CONTINUES TO WORK EAST.
LIGHT WEST WINDS WILL GENERALLY PREVAIL THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
125 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1105 PM EDT FRI MAR 20 2015
HOURLY GRIDS WERE UPDATED BASED ON RECENT RADAR AND OBSERVATION
TRENDS. AREAS OF DRIZZLE CONTINUE ACROSS THE RADAR PER OBS AND
RADAR IMAGERY GENERALLY SOUTH OF INTERSTATE 64 AND EAST OF
INTERSTATE 75. THIS SHOULD GRADUALLY DIMINISH AS THE MOISTURE
BECOMES SHALLOWER. PATCHY FOG IS STILL ANTICIPATED AND MAY BE
DENSE AT TIMES ON SOME RIDGES. CLOUDS SHOULD NOT SCATTER OUT UNTIL
AROUND DAYBREAK...EXCEPT PERHAPS IN THE FAR NORTHWEST.
UPDATE ISSUED AT 815 PM EDT FRI MAR 20 2015
AREAS OF DRIZZLE HAVE DEVELOPED WITH AN UPSLOPE COMPONENT ACROSS
THE REGION. THIS LOW LEVEL MOISTURE WILL BECOME SHALLOWER AS THE
NIGHT PROGRESSES...WHICH SHOULD END THE DRIZZLE...BUT LOW CLOUDS
WILL REMAIN. SOME PATCHY FOG IS ANTICIPATED AND THIS COULD BECOME
DENSE ON THE RIDGES THROUGH STRATUS BUILD DOWN. THIS THREAT WILL
CONTINUE TO BE MONITORED. LOW CLOUDS HAVE CLEARED ACROSS PARTS OF
WESTERN IL...FAR WESTERN KY AND TN...BUT IT WILL PROBABLY BE AFTER
SUNRISE BEFORE THE LOW CLOUDS BEGIN TO LIFT ACROSS EASTERN KY.
MODEL TIME HEIGHT SECTIONS AND FORECAST SOUNDINGS SUGGEST THE LOW
CLOUDS LINGERING PAST 8 AM ON SATURDAY IN MANY LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 310 PM EDT FRI MAR 20 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF
KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA.
THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME
POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW
CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE
RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID
TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN
THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A
DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A
SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON
WEST TO NORTHWEST WINDS OF 5 TO 10 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM.
THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS
EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE
NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL
HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN
BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A
BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY
AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE
ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO
SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY
MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER
RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT
TERM.
SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH
BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG
AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE
FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP.
IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN
ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED
THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE
NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS
WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND
PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA
SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN
LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL
RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY
NIGHT...DESPITE THE HIGH CLOUDS.
USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS
WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS
WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z
TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM EDT FRI MAR 20 2015
THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN
PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT
THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE
END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST
TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE
WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A
WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL
WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND.
IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE
WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY
TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST
U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM
SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN
IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH
AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A
STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE
OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A
COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE
GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION
CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS
TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN.
HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT
THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 125 AM EDT SAT MAR 21 2015
LOW CLOUDS AND DRIZZLE STILL HANGING IN AT MANY SITES TONIGHT.
AREAS OF DRIZZLE ARE EXPECTED TO CONTINUE TO SUBSIDE OVERNIGHT AS
DRIER AIR SLOWLY WORKS EAST. MOST SITES WILL STAY IFR OR MVFR
THROUGH MID MORNING AT THE LATEST BEFORE WE BEGIN TO SEE SKIES
SCATTER OUT FROM WEST TO EAST. VFR CONDITIONS RETURN FOR MUCH OF
THE END OF THE TAF PERIOD AS DRYER AIR CONTINUES TO WORK EAST.
LIGHT WEST WINDS WILL GENERALLY PREVAIL THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1112 PM CDT FRI MAR 20 2015
.UPDATE...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
AVIATION UPDATE.
UPDATE ISSUED AT 940 PM CDT FRI MAR 20 2015
UPDATED FORECAST TO INCREASE SKY COVER THROUGH THE REMAINDER OF THE
NIGHT. AS LOW CLOUDS CONTINUE TO CLEAR...HIGH CLOUDS ARE ON THE
INCREASE. MODEL FORECAST OF 300 MB DEWPOINT DEPRESSION SUGGESTS THIS
HIGH CLOUD COVER WILL LIKELY STICK AROUND THROUGH MUCH OF THE NIGHT.
REMAINDER OF FORECAST IS UNCHANGED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
LOW LEVEL TRAJECTORIES NOT FAVORABLE FOR RAPID CLEAR OUT...BUT
SLOWLY OVER TIME...HIGH PRESSURE WORKS IN AND ACROSS THE TENNESSEE
VALLEY AND OVERALL SUBSIDENCE/DRYING THROUGH THE COLUMN SHOULD WIN
OUT...CERTAINLY...BY TMRW. THIS WILL RESULT IN A NICE WARMUP WITH
TEMPS CLIMBING THRU THE 60S AND FLIRTING WITH/REACHING TOWARD 70
ESP ACROSS OUR SOUTH/WEST.
A MORE OR LESS ZONAL FLOW THEN RIDES OUT THE REMAINDER OF THE
SHORT TERM AND CARRIES THE FORECAST THRU THE WEEKEND. ENERGY IN
THE FLOW PATTERN TO OUR NORTH AND SOUTH MEANS MORE CLOUDS SUNDAY
THAN SATURDAY...AND AS A RESULT...TEMPS MAY NOT CLIMB AS HIGH BUT
WILL STILL BE RELATIVELY PLEASANT IN THE 60S.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 1249 PM CDT FRI MAR 20 2015
HIGH CONFIDENCE THROUGH MID WEEK....DECREASING TO LOW CONFIDENCE
AFTER THURSDAY.
THE MODELS ARE IN GOOD AGREEMENT WITH NEXT SYSTEM TO MOVE THROUGH
MID WEEK...BUT AFTER THAT THEY DIVERGE A GREAT DEAL. THEY BOTH KEEP
US UNDER A SLOW MOVING UPPER TROUGH BUT DIFFER IN SPOKES OF ENERGY
MOVING THROUGH THE TROF AND AVAILABLE MOISTURE. THE GFS CONTINUES TO
SHOW NUMEROUS SPOKES OF ENERGY PRODUCING LIGHT RAIN AFTER THE MAIN
COLD FRONT PASSAGE IN CONTRAST TO SEVERAL RUNS OF THE ECMWF WHICH
KEEPS US DRY AFTER THURSDAY. MAY HAVE SOME SLIGHT CHANCES IN FOR THE
POSSIBILITY THE GFS VERIFIES BUT WILL WAIT AND SEE WHAT THE EXTENDED
INIT YIELDS AND TAKE IT FROM THERE. I INTRODUCED THUNDER YESTERDAY
AND NOW THINK IT WILL BE SURFACE BASED WITH LI`S AT THE SURFACE
YIELDING -1 TO -4. ALSO K INDEX 30 AND ABOVE WITH SHOWALTER ZERO
TO -4. WILL KEEP TRW- OVER THE ENTIRE AREA THROUGH 00Z THURSDAY
AND THEN TAPER IT OFF TO ALONG AND SOUTHEAST OF THE OHIO RIVER
0-06Z THU. PLAN ON TAKING THUNDER COMPLETELY OUT AFTER 06Z
THURSDAY. THE THUNDER WILL BE POSSIBLE IN THE WARM SECTOR AFTER
THE WARM FRONT HAS LIFTED NORTH AND AHEAD OF THE APPROACHING COLD
FRONT FROM THE NORTHWEST.
SLIGHTLY ABOVE NORMAL TEMPERATURES FOR MOST OF THE WORK WEEK WILL
FALL BELOW NORMAL IN THE COLD FRONTS WAKE AT THE END OF THE WORK
WEEK.
&&
.AVIATION...
ISSUED AT 1112 PM CDT FRI MAR 20 2015
CONSIDERABLE HIGH CLOUDS OVERNIGHT. WINDS NOT ENTIRELY CALM
THROUGH 06Z. GUIDANCE SUGGESTS CALM BUT THE RAP 13KM SAYS IT MAY
NOT STAY THAT WAY (2-3 KTS AT TIMES). GIVEN BOTH FACTORS...WILL
LIMIT THE FOG MENTION. HIGH CLOUDS WILL PERSIST THROUGH SATURDAY
AS WELL WITH LIGHT WINDS CONTINUING...MAINLY WITH A SSW COMPONENT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
301 AM EDT SAT MAR 21 2015
.SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
&&
.MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.AVIATION...ISSUED 121 AM EDT SAT MAR 21 2015
MVFR CEILING WILL CONVERGE ON THE SE MICHIGAN TERMINAL CORRIDOR
DURING THE EARLY MORNING FROM THE NORTH WITH A COLD FRONT AND FROM
THE SOUTH WHERE AN AREA OF MVFR CEILING RESIDES OVER INDIANA AND
OHIO. LIGHT PRECIPITATION MAY BRUSH THE MBS TERMINAL BUT THE
BOUNDARY LAYER WILL REMAIN WARM ENOUGH FOR ALL RAIN BEFORE SINCE THE
PRECIPITATION WILL BE MOSTLY EAST OF THE TERMINAL BEFORE THE COLD
FRONT ARRIVES. NORTHWEST WIND GUSTING TO AROUND 20 KNOTS WILL THEN
BRING DRY AND COLDER AIR INTO THE REGION THAT WILL LEAD TO A
DIMINISHING CLOUD TREND DURING THE AFTERNOON INTO SATURDAY NIGHT.
FOR DTW... INCONSISTENT COVERAGE OF VFR CEILING BELOW 5000 FT WILL
PRECEDE MVFR CEILING POISED TO DEVELOP NORTHWARD FROM INDIANA AND
OHIO BEFORE SUNRISE. THESE CLOUDS WILL MERGE WITH MVFR CEILING ALONG
AND BEHIND A COLD FRONT SET TO MOVE THROUGH DTW MID TO LATE MORNING.
A CLEARING TREND WILL THEN GET UNDERWAY DURING THE AFTERNOON AS DRY
AND COLDER AIR MOVES INTO THE REGION.
//DTW THRESHOLD PROBABILITIES...
* MODERATE FOR CEILING BELOW 5000 FT FOR THE REST OF TONIGHT THROUGH
EARLY AFTERNOON.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
AVIATION.....BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1149 PM CDT Fri Mar 20 2015
.UPDATE:
Issued at 715 PM CDT Fri Mar 20 2015
Cirrus clouds are much thicker than originally anticipated based
on ground obs and visible satellite before the sun went down. Have
boosted sky cover for this evening for most of the area with the
trend expected to be for the thicker cloud cover to sag south a
bit overnight. SW surface winds also won`t allow much of a temp
drop either and so edged min temps up a deg or two as well for
many areas. Only in the far northern CWA around UIN will the
forecast be relatively unaffected.
TES
&&
.SHORT TERM: (Through Tonight)
Issued at 250 PM CDT Fri Mar 20 2015
Focus tonight will be temps.
Clouds continue to struggle to dissipate this afternoon. It appears
the RAP is handling these clouds the best for now. Nrn edge of the
clouds shud continue slowly moving ewd. Further S, believe clouds
will continue to dissipate and move newd. A section of the nrn
clouds from near KCOU to KUIN will likely be the last to dissipate
or advect out of the area. Across the srn portions of the CWA, CI
has already begun to move into the area and will continue to do so
overnight. However, it is a little uncertain how thick these clouds
will be.
Have trended twd the cooler guidance tonight partially because of
anticipating the clearing. However, going forecast may not be cold
enuf since temps struggled today.
Tilly
.LONG TERM: (Saturday through Next Friday)
Issued at 250 PM CDT Fri Mar 20 2015
A cdfnt shud have arrived across the nrn third of the CWA by 12z
Sat. This fnt will continue to push swd thru the day. While this may
be a cold fnt, with nearly full insolation expected, tomorrow shud
actually be warmer than today. Mdls also push the thermal ridge
across the region on Sat. The fnt begins to lift nwd on Sun as a sfc
low and associated s/w approach the region. While not high chances,
this system will bring a chance for RA across nrn portions of the
CWA Sun night and across much of the area on Mon, more probable
during the afternoon with heating.
As the trof deepens across the Plains and the LLJ increases with
what shud be an open Gulf, precip chances increase quickly Mon night
and Tues, with TS becoming more probable as well. Going forecast
PoPs may be too low attm, but have not gone higher for now due to
lack of persistence among mdl guidance. Given the amount of shear
available with the system on Tues, there is a very narrow window
where severe weather potential exists. However, given a number of
questions regarding timing with this event, will hold off mention in
products now other than that it remains to be a system to watch.
Behind the cdfnt late Wed and a secondary cdfnt on Thurs, the
potential for a very cold rain or possibly even light snow event
exists. Have kept as RA for now, but again, will be a system to
monitor.
Tilly
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1135 PM CDT Fri Mar 20 2015
Cirrus is expected to continue to stream ENE from the sthrn
Plains thru the fcst prd...esp across sthrn MO and sthrn IL. There
may still be some MVFR fog towards 12Z...but the thick cirrus may
limit fog potential with KUIN being the exception since they are
north of the densest cloud cover. A weak bndry will push thru the
area Sat mrng causing winds to go from S/SW sat mrng to NE by late
aftn as a sfc ridge noses into the Grt Lks region out of Canada.
Winds are expected to remain aob 10kts.
Specifics for KSTL:
VFR fcst thru the prd. Removed the high end MVFR fog with current
thinking that the thick cirrus expected for the rest of the night will
hold temps up enough so the cross over temp is not reached. Otherwise
expect a slowly backing wind from mid mrng thru the aftn as a weak
cold front slides thru.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1123 PM CDT FRI MAR 20 2015
.SYNOPSIS...
ISSUED AT 340 PM CDT FRI MAR 20 2015
H5 ANALYSIS FROM EARLIER THIS MORNING CONTINUES TO
INDICATE RIDGING ACROSS THE WESTERN CONUS WITH A CUTOFF LOW OVER
PORTIONS OF SOUTHERN BAJA CALIFORNIA. A DECENT SHORTWAVE WAS NOTED
OVER SRN COLORADO. NORTH OF THE BORDER...LOW PRESSURE WAS NOTED OVER
HUDSON BAY AND A SECOND LOW WAS NOTED SOUTH OF GREENLAND. ANOTHER
LOW WAS LOCATED SOUTH OF THE ALEUTIANS OF ALASKA WITH A TANDEM OF
SHORTWAVES ON THE SRN AND SERN PERIPHERY OF THIS FEATURE. WV IMAGERY
FROM THIS AFTERNOON IS INDICATING A NICE PLUME OF UPPER LEVEL
MOISTURE...STREAMING INTO THE PACIFIC NORTHWEST AND THE CANADIAN
ROCKIES. ANOTHER AREA OF ABUNDANT HIGH LEVEL MOISTURE WAS NOTED FROM
MEXICO INTO TEXAS AND THE SERN STATES. ACROSS THE CENTRAL
CONUS...DRYING WAS NOTED WITH CLEAR SKIES IN PLACE ACROSS WESTERN
AND NORTH CENTRAL NEBRASKA. AT THE SURFACE...LOW PRESSURE WAS
LOCATED OVER CENTRAL NORTH DAKOTA WITH A DECENT TROUGH OF LOW
PRESSURE EXTENDING SWD INTO CENTRAL AND SRN NEBRASKA. WINDS WERE
FROM THE WEST AND WEST SOUTHWEST AT 10 TO 20 MPH THIS
AFTERNOON...WITH A FEW GUSTS TO 30 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
CLEAR SKIES AND LIGHT WINDS ARE EXPECTED TONIGHT. A WEAK BACK DOOR
COLD FRONT WILL TRY TO PUSH SOUTHWEST INTO THE AREA...AND SHOULD
PUSH THROUGH THE ONEILL AREA AND STALL ALONG A LINE FROM BROKEN BOW
TO AINSWORTH LATE TONIGHT. THE ONLY NOTICEABLE DIFFERENCE ASSOCIATED
WITH THE FRONT WILL BE A SHIFT IN THE WIND TO LIGHT NORTHEAST AS THE
FRONT PASSES. TEMPERATURES WILL REALLY NOT BE MUCH DIFFERENT ON
EITHER SIDE OF THE FRONT.
A SHORTWAVE TROUGH WILL MOVE INTO MONTANA FROM THE WEST LATER
SATURDAY. AHEAD OF THIS FEATURE...SURFACE LOW PRESSURE WILL DEEPEN
AND MOVE EAST ALONG THE NE/SD BORDER DURING THE DAY. A WARM FRONT
WILL EXTEND SOUTHEAST FROM THE LOW CENTER...AND WILL ADVANCE EAST
ACROSS THE AREA DURING THE DAY SATURDAY. BOTH THE NAM AND GFS ARE IN
GOOD AGREEMENT AND HAVE THE LOW NEAR VALENTINE BY LATE
AFTERNOON...WITH THE WARM FROM ARCING SOUTHEAST FROM THE LOW CENTER
TOWARD BROKEN BOW. TO THE EAST OF THE WARM FRONT...WINDS WILL REMAIN
BACKED A BIT TO THE SOUTHEAST...WITH TEMPERATURES PROBABLY NOT
REACHING MUCH ABOVE 65 DEGREES. TO THE WEST OF THE WARM
FRONT...SOUTHWEST TO WESTERLY DOWNSLOPE WEST WINDS WILL COMBINE WITH
A PLUME OF WARM AIR ALOFT /H850MB TEMPS NEAR 17C/ WITH HIGHS WELL
INTO THE 70S. SOUNDING PROFILES INDICATE A DEEPLY MIXED
ATMOSPHERE...SO THINK A FIRE WEATHER WATCH IS NEEDED FOR AREAS ALONG
AND WEST OF THE WARM FRONT ACROSS WESTERN NEBRASKA. WINDS MAY BE
MARGINAL...BUT WITH THE VERY DRY AIR AND DEEP MIXING FEEL A WATCH IS
NEEDED.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 340 PM CDT FRI MAR 20 2015
MID RANGE...SATURDAY NIGHT THROUGH MONDAY...FOR SATURDAY NIGHT
THROUGH MONDAY...TEMPERATURES WILL BE THE MAIN FORECAST CHALLENGE.
ON SATURDAY NIGHT...SURFACE LOW PRESSURE WILL TRACK FROM THE
PANHANDLE INTO CENTRAL PORTIONS OF THE FORECAST AREA. WITH THE LOW
OVER CENTRAL PORTIONS OF THE FORECAST AREA...LOW LEVEL MOISTURE WILL
BE SHOVED EAST OF THE FORECAST AREA...WHICH WILL ALLOW MINS TO DROP
OFF INTO THE 30S SATURDAY NIGHT. IF THE LOW CONTINUES TO TREND
FARTHER EAST...WILL NEED TO DROP LOWS A BIT FURTHER AS DRIER AIR
WILL BE DRAWN FURTHER EAST FROM THE PANHANDLE. ON SUNDAY...LOW
PRESSURE WILL DROP SOUTH INTO KANSAS WITH A COLD FRONT EXTENDING
FROM SERN NEBRASKA INTO SWRN KS. WINDS WILL BE GUSTY INITIALLY
BEHIND THE FRONT WITH DECREASING WINDS IN THE AFTERNOON HOURS.
YESTERDAY...WAS CONCERNED SOME ABOUT HAZARDOUS FIRE DANGER CONDS
SUNDAY AFTERNOON...HOWEVER...BOTH THE NAM AND GFS THIS MORNING HAVE
DEW POINTS IN THE 20S BEHIND THE FRONT...WHICH IS A SLIGHT INCREASE
FROM YESTERDAY. ALSO...HIGHS TRENDED A LITTLE COOLER AS WELL...SO
MIN RH/S ARE NOT AS CRITICAL NOW. ATTM...DECIDED TO TREND HIGHS
SUNDAY A TAD COOLER WITH UPPER 50S IN THE NORTHEAST TO UPPER 60S IN
THE FAR SOUTHWEST. ON SUNDAY NIGHT...MID LEVEL WARM AIR ADVECTION
WILL BEGIN TO INCREASE IN THE PANHANDLE AND NORTHWEST OVERNIGHT
LEADING TO INCREASED CLOUDINESS AND AN OUTSIDE CHANCE OF A SHOWER IN
THE NORTHWEST. ON MONDAY SURFACE LOW PRESSURE WILL CONTINUE TO
DEEPEN ACROSS EASTERN WYOMING...LEADING TO INCREASED SOUTHEASTERLY
FLOW FLOW. WITH AN EASTERLY COMPONENT TO THE LOW LEVEL WINDS MONDAY
AND INCREASED LOW LEVEL MOISTURE ADVECTION...DECIDED TO DROP HIGHS A
TAD MONDAY FROM THE INHERITED FCST. THIS YIELDED HIGHS IN THE 60S
ACROSS THE FORECAST AREA.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY...DECENT LOW LEVEL MOISTURE
ADVECTION WILL CONTINUE MONDAY NIGHT WITH DEW POINTS REACHING THE
LOWER 40S ACROSS THE EASTERN 2/3RDS OF THE FORECAST AREA OVERNIGHT.
A LEAD SHORTWAVE WILL APPROACH THE PANHANDLE LATE MONDAY
NIGHT...LEADING TO INCREASED ELEVATED INSTABILITY. AS WAS THE CASE
YESTERDAY...H850 LI/S RANGE FROM 0 TO -2C ACROSS THE EASTERN 2/3RDS
OF THE FORECAST AREA LATE MONDAY NIGHT. INHERITED FCST HAD A MENTION
OF THUNDER AND WILL KEEP THIS INTACT WITH THE AFTERNOON PACKAGE. ON
TUESDAY...SURFACE LOW PRESSURE WILL QUICKLY LIFT INTO SOUTH DAKOTA
BY MIDDAY...FORCING THE DRYLINE INTO EASTERN NEBRASKA BY 18Z. STILL
HELD ONTO SOME SLIGHT CHANCE POPS...FOR ANY RESIDUAL THUNDERSTORMS
TUESDAY MORNING. THE AFTERNOON WILL BE DRY AND WINDY...AND WILL
LIKELY NEED SOME SORT OF FIRE HEADLINE...ESPECIALLY IN THE WEST
WHERE SFC DEW POINTS REACH THE SINGLE DIGITS BY TUESDAY AFTERNOON.
WILL CONTINUE TO HIT THE FIRE DANGER TUESDAY HARD IN THE HWO SINCE
CONFIDENCE CONTINUES TO INCREASE IN THIS HAPPENING. BEYOND
TUESDAY...THE PATTERN WILL BEGIN TO AMPLIFY ACROSS THE CONUS WITH
RIDGING ACROSS THE WESTERN THIRD OF THE CONUS AND A DEEPENING TROUGH
OVER THE GREAT LAKES SWD TO THE NRN GULF COAST. ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...MUCH COOLER TEMPS WILL ARRIVE ON WEDNESDAY
AND WILL PERSIST THROUGH FRIDAY. WITH THE MODELS TRENDING TOWARD A
DRIER PATTERN LATE NEXT WEEK...WILL LEAVE THE FCST DRY BEYOND
TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1122 PM CDT FRI MAR 20 2015
VFR IS EXPECTED ALL AREAS OVERNIGHT THRUOGH SATURDAY EVENING.
A WEAK COLD FRONT LOCATED IN THE PLATTE VALLEY WILL BE LIFTED
NORTH AS LOW PRESSURE ACROSS THE NRN HIGH PLAINS TRACKS INTO
NEBRASKA SATURDAY AND SATURDAY NIGHT. GENERALLY CLEAR SKIES ARE
EXPECTED DURING THIS TIME.
&&
.FIRE WEATHER...
ISSUED AT 756 PM CDT FRI MAR 20 2015
WINDS HAVE DECREASED AS EXPECTED AND THE RED FLAG WARNING HAS BEEN
ALLOWED TO EXPIRE.
THE STRONGER WIND SPEEDS SATURDAY AFTN APPEAR TO BE NORTH OF
INTERSTATE 80 AND GENERALLY ALONG AND EAST OF HIGHWAY 61
SUGGESTING RED FLAG CONDITIONS ARE MOST LIKELY IN THIS AREA. THIS
IS BASED ON A MULTI MODEL BLEND APPROACH. THERE ARE NO STAND OUT
SOLNS EXCEPT FOR THE GEM REGIONAL WHICH SHOWED THE STRONGEST WINDS.
TONIGHTS MODEL RUNS AND THE RAP MAY TREND TOWARD THE GEM MODEL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
EVENING FOR NEZ204-206-210-219.
&&
$$
SYNOPSIS...CLB
SHORT TERM...TAYLOR
LONG TERM...CLB
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
441 AM EDT SAT MAR 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE AREA TODAY. LOW PRESSURE WILL
PASS SOUTHEAST OF THE REGION LATE SUNDAY INTO TUESDAY. HIGH
PRESSURE WILL BUILD OVER THE AREA WEDNESDAY. A COLD FRONT WILL
APPROACH THE AREA ON THURSDAY STALLING JUST OF THE REGION THURSDAY
NIGHT. LOW PRESSURE WILL MOVE ALONG THIS FRONT FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 4 AM SATURDAY...THE LATEST SURFACE ANALYSIS SHOWS THE 1008
MB LOW PRESSURE SYSTEM APPROX 225 MILES EAST OF OCEAN CITY, MD
WITH A 1020 MB HIGH CENTERED OVER MD. THE LOW WILL CONTINUE TO
LIFT NE TODAY WITH THE HIGH MIGRATING SOUTH ACROSS THE AREA
THROUGH THE DAY AND SETTLING OFFSHORE LATE THIS AFTERNOON AND
EVENING, ALLOWING LIGHT N WINDS TO BACK TO W THIS AFTERNOON THEN
SW LATE TODAY. STRATUS CONTINUES TO ADVECT SOUTH ACROSS THE AREA
EARLY THIS MORNING WITH ONLY SWRN PORTIONS OF ONSLOW AND DUPLIN
COUNTIES CLEAR, HOWEVER EXPECT THESE AREAS TO BECOME CLOUDY OVER
THE NEXT HOUR TO SO. THE STRATUS WILL LIKELY LINGER MID TO LATE
MORNING BEFORE ERODING AND THE HRRR EVEN HOLDS ON TO IT ACROSS THE
COASTAL PLAIN UNTIL EARLY AFTERNOON, THEN SUNNY TO PARTLY CLOUDY
SKIES EXPECTED TO DEVELOP THIS AFTERNOON. TEMPS WILL LIKELY HOLD
IN THE 40S TO LOWER 50S THIS MORNING WITH CLOUD COVER, BUT ONCE
THE LOW CLOUDS ERODE EXPECT TEMPS TO WARM INTO THE MID 60S INLAND
WHILE HIGHS IN THE LOW TO MID 50S CAN BE EXPECTED ACROSS THE
NORTHERN BEACHES AND UPPER 50S TO AROUND 60S SOUTHERN BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
AS OF 4 AM SATURDAY...SFC HIGH PRES OFFSHORE DISSIPATES TONIGHT
WITH A BACKDOOR COLD FRONT PUSHING SOUTH ACROSS THE MID ATLANTIC
STATES. THE FRONT IS EXPECTED TO BE JUST SOUTH OF THE VA/NC
BORDER AROUND 12Z SUNDAY. EXPECT MAINLY CLEAR SKIES THROUGH THE
EVENING HOURS BUT INCREASING MID AND HIGH CLOUDS EXPECTED AFTER
MIDNIGHT AS SOUTHERN STREAM MOISTURE LIFTS NORTH ACROSS THE GULF
STATES AND SOUTHEAST. LIGHT SW WINDS CONTINUE THROUGH THE
OVERNIGHT WITH LOWS A FEW DEGREES WARMER THAN TODAY, MAINLY IN THE
MID 40S. HYDROLAPSE RATES SUPPORT FOG DEVELOPMENT TONIGHT HOWEVER
CROSSOVER TEMPS ARE NOT EXPECTED TO BE REACHED AND GUIDANCE IS NOT
DEVELOPING FOG SO WILL NOT PUT IN THE FORECAST AT THIS TIME.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 355 AM SATURDAY...EARLY IN THE PERIOD THE UPPER LOW
VICINITY OF BAJA MEXICO WILL MOVE EASTWARD AS AN OPEN WAVE
DAMPENING IN THE CONFLUENT FLOW OVER THE EASTERN US. THIS SYSTEM
WILL PRODUCE CYCLOGENESIS ALONG A WAVY STALLED FRONT SOUTH OF THE
REGION. A SERIES OF BROAD LOW PRESSURE AREAS ARE FORECAST TO PASS
SOUTH OF THE REGION THROUGH MONDAY NIGHT. MAIN QUESTION IS
PLACEMENT AND AMOUNTS OF PRECIPITATION ASSOCIATED WITH THIS
SYSTEM. THE GFS HAS TRENDED WETTER AND NOW ALL THE OPERATIONAL
MODELS ARE INDICATING RAIN ACROSS PORTIONS OF EASTERN NC SUNDAY
THROUGH MONDAY ALTHOUGH THERE ARE SIGNIFICANT DIFFERENCES AMONG THEM.
THE GUIDANCE IS INDICATING THE POTENTIAL FOR A SHARP MOISTURE
GRADIENT ACROSS EASTERN NC AS HIGH PRESSURE TO THE NORTH INHIBITS
PRECIPITATION DEVELOPMENT ACROSS THE NORTHERN ZONES. CONSENSUS OF
THE GUIDANCE SUGGESTS BEST PRECIPITATION POTENTIAL SOUTH OF
HIGHWAY 64 WITH ONLY LIGHT AMOUNTS EXPECTED TO THE NORTH. THE
HEAVIEST RAINS SHOULD OCCUR ALONG AND SOUTH OF HIGHWAY 70. THINK
LIGHT RAIN DEVELOPS SOMETIME SUNDAY AFTERNOON AND THEN BECOMES A
LITTLE MORE WIDESPREAD SUNDAY NIGHT AND MONDAY AS THE REGION
COMES UNDER THE INFLUENCE OF THE LEFT FRONT QUAD OF THE UPPER JET.
WAS TEMPTED TO RAISE POPS SOUTHERN AREAS TO LIKELY BUT THINK ITS
WORTH WAITING 1 MORE MODEL RUN TO SEE IF THE MODELS NARROW THE GAP
BETWEEN THEM. THE PRECIPITATION IS EXPECTED TO COME TO AN END
MONDAY NIGHT AS HIGH PRESSURE BUILDS OVER THE AREA FROM THE NORTH.
HIGH TEMPERATURES TRICKY FOR SUNDAY AS CLOUDS/NORTHERLY FLOW AND
POSSIBLE PRECIPITATION WILL LIMIT WARMING BUT STILL THINK LOWER TO
MIDDLE 60S A GOOD BET ACROSS MOST OF THE AREA AWAY FROM COLDER
NEAR SHORE WATERS. TEMPERATURES SUNDAY COULD DROP INTO THE UPPER
30S IN STRENGTHENING NORTHERLY FLOW WHICH CONTINUES MONDAY WITH
CLOUDY SKIES/PRECIPITATION PRODUCING BELOW NORMAL HIGHS IN THE
LOWER 50S.
SHOULD HAVE A COUPLE OF DRY DAYS TUESDAY AND WEDNESDAY AS HIGH
PRESSURE BUILDS OVER THE AREA. HIGHS TUESDAY WILL CONTINUE BELOW
NORMAL IN THE MID TO UPPER 50S MOST AREAS WITH MODERATING
SOUTHERLY FLOW PRODUCING WARMER MID TO UPPER 60S AWAY FROM THE
BEACHES.
THERE ARE STILL DIFFERENCES FOR LATE IN THE WEEK AS A STRONG COLD
FRONT MOVES ACROSS THE EASTERN US BUT IT APPEARS THE COLD FRONT
WILL CROSS THE AREA THURSDAY NIGHT STALLING JUST TO THE SOUTH.
THEN FRIDAY A WAVE OF LOW PRESSURE WILL DEVELOP AND MOVE EAST
ALONG THE FRONT. RESULT OF THIS WILL BE THE POTENTIAL FOR
UNSETTLED WEATHER THURSDAY AND FRIDAY. HIGHS ON THURSDAY SHOULD BE
ABLE TO WARM WELL INTO THE 70S WITH COOLER TEMPS IN THE 60S
FRIDAY. HIGHS COULD BE EVEN LOWER DEPENDING ON HOW MUCH COLD AIR
CAN FILTER IN BEHIND THE FRONT.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 210 PM FRI...AN AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA AND HAS REACHED THE HIGHWAY 70 CORRIDOR AFFECTING ALL TAF
SITES BUT OAJ TO THIS POINT, HOWEVER EXPECT IT TO REACH OAJ IN THE
NEXT HOUR OR TWO. VSBYS HAVE REMAINED GOOD BUT CIGS HAVE BEEN
GENERALLY AROUND 1-1.5K FT, OCCASIONALLY DROPPING JUST BELOW INTO
THE IFR RANGE.
HIGH CONFIDENCE THAT MVFR CIGS WILL PREVAIL AT THE TERMINALS EARLY
THIS MORNING BUT HAVE BELOW NORMAL CONFIDENCE FOR POTENTIAL IFR
CONDITIONS AS GUIDANCE NOT IN BEST AGREEMENT WITH AREAL EXTENT
AND HEIGHT OF THE STRATUS. NAM MOS IS UNDERDONE WITH THE STRATUS
WHILE THE GFS MOS APPEARS TOO PESSIMISTIC WITH IFR/LIFR ALREADY
IN PLACE WHERE CONDITIONS REMAIN MVFR. GENERALLY FOLLOWED UPSTREAM
TRENDS ALONG WITH THE GFS LAMP WHICH DOES BRING A PERIOD OF IFR TO
PGV AND ISO DURING THE PRE-DAWN HOURS AND KEEPS EWN AT MVFR. DID
BRING MVFR CIGS TO OAJ LOOKING AT TRENDS DESPITE MOST GUIDANCE
KEEPING CONDITIONS VFR FOR THE MOST PART. THE HRRR HOLDS ON TO THE
STRATUS MUCH LONGER THIS MORNING WHILE MOS GUIDANCE APPEARS TO
ERODE IT AROUND 12Z, WHICH IS LIKELY TOO QUICK AND HELD ONTO MVFR
CONDITIONS UNTIL 14-15Z, HOWEVER HRRR IS EVEN LATER THAN THIS,
ESPECIALLY ACROSS THE COASTAL PLAIN.
EXPECT LIGHT NORTHERLY WINDS THIS MORNING, BACKING TO SOUTHWEST
THIS AFTERNOON AND EVENING AS HIGH PRES SLIDES SOUTH ACROSS THE
AREA. PREDOMINANTLY VFR CONDITIONS EXPECTED THIS AFTERNOON AND
EVENING. FOG IS QUESTIONABLE TONIGHT. HYDROLAPSE RATES ARE
FAVORABLE FOR FOG DEVELOPMENT HOWEVER CROSSOVER TEMPS ARE NOT
EXPECTED TO BE REACHED AND MOS GUIDANCE KEEPING VFR CONDITIONS,
THEREFORE WILL NOT ADD FOG TO THE FORECAST AT THIS TIME.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM SATURDAY...VFR CONDITIONS SHOULD CONTINUE INTO
SUNDAY AFTERNOON AS HIGH PRES BUILDS INTO THE AREA. A SERIES OF
WEAK LOWS DEVELOP TO THE S SUNDAY AND SLOWLY LIFT NE MON. STILL
UNCERTAINTY WITH HOW MUCH MOISTURE WILL STREAM NORTH INTO EASTERN
NC BUT THERE WILL BE A POTENTIAL FOR MVFR CONDITIONS...ESPECIALLY
SRN TAF SITES SUNDAY EVENING THRU MON EVE. DRIER WEATHER AND
PREVAILING VFR CONDITIONS ARE EXPECTED FOR TUESDAY AND WEDNESDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 430 AM SATURDAY...N WINDS CONTINUE AROUND 10-20 KT WITH
HIGHER GUSTS OFF THE OBX THIS MORNING BUT WILL BE DIMINISHING
THROUGH THE DAY AND HIGH PRES MIGRATES SOUTH ACROSS THE AREA
TODAY. VARIABLE WINDS LESS THAN 10 KT EXPECTED THIS AFTERNOON,
BECOMING SW THIS EVENING AND INCREASING UP TO 15 KT LATE TONIGHT
AHEAD OF A BACKDOOR COLD FRONT, WHICH IS PROGGED TO BE JUST NORTH
OF THE WATERS AT 12Z SUNDAY. CONTINUE TO FOLLOW NWPS CLOSELY FOR
SEAS WITH A LACK OF BUOY OBS ACROSS THE CWA BUT IT APPEARS TO BE
HANDLING CONDITIONS A BUOYS NORTH AND SOUTH OF THE REGION WELL.
WILL CONTINUE SCA NORTH OF OCRACOKE INLET THROUGH 11 AM FOR SEAS
AROUND 4-7 FT. SEAS EXPECTED TO SUBSIDE TO 3-5 FT THIS AFTERNOON
AND 2-4 FT TONIGHT. THE SOUTHERN WATERS WILL SEE 3-5 FT SEAS THIS
MORNING, SUBSIDING TO 2-3 FT THIS AFTERNOON AND TONIGHT.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM SATURDAY...MARINERS CAN EXPECT ROUGH CONDITIONS
SUNDAY NIGHT INTO TUESDAY. LIGHT WINDS EARLY SUNDAY WITH HIGH
PRESSURE OVER THE AREA WILL INCREASE OUT OF THE NORTH TO 15 TO 20
KT IN THE AFTERNOON. DEVELOPING LOW PRESSURE MOVING TO THE SOUTH
SUNDAY NIGHT AND MONDAY WILL TIGHTEN THE GRADIENT STRENGTHENING
THE NORTH TO NORTHEAST FLOW TO 20 TO 30 KT LATE SUNDAY NIGHT
THROUGH MONDAY EVENING. THERE IS POTENTIAL FOR A LOW END GALE
DURING THIS PERIOD OVER THE SOUTHERN AND CENTRAL WATERS. SEAS WILL
BUILD TO 7 TO 9 FT. WINDS WILL GRADUALLY DIMINISH LATE MONDAY
NIGHT TO 15 TO 25 KT AND 10 TO 20 KT TUESDAY WITH SEAS EXPECTED TO
DIMINISH BELOW 6 FT BY EVENING. VEERING WINDS FROM NE TO SE 10 TO
15 KT ARE EXPECTED ON WEDNESDAY AS HIGH PRESSURE TO THE NORTH
MOVES OFFSHORE. SEAS ARE FORECAST TO BE IN THE 2-4 FT RANGE.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ150-
152-154.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...JME
AVIATION...JME/SK
MARINE...JME/SK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
250 AM EDT SAT MAR 21 2015
.SYNOPSIS...
LOW PRESSURE WILL CONTINUE TO MOVE NORTHEAST AWAY FROM THE NORTH
CAROLINA COAST OVERNIGHT. HIGH PRESSURE WILL BUILD IN SATURDAY.
ANOTHER LOW PRESSURE WILL PASS SOUTHEAST OF THE REGION LATE SUNDAY
INTO TUESDAY. HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY. A
COLD FRONT WILL APPROACH THE AREA ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 2 AM SATURDAY...AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA EARLY THIS MORNING AND HAS REACHED THE HIGHWAY 70
CORRIDOR AS OF 2 AM. EXPECT IT TO PUSH INTO SOUTHERN AREAS OVER
THE NEXT FEW HOURS. FOR THE MOST PART GUIDANCE IS KEEPING
VISIBILITIES 6 MILES OR GREATER AND UPSTREAM OBS ALL REPORTING
GOOD VISIBILITIES THEREFORE HAVE REMOVED FOG FROM THE FORECAST
BUT DID BUMP UP SKY COVER TO ACCOUNT FOR THE STRATUS.
THE LATEST SURFACE ANALYSIS SHOWS THE 1007 MB LOW PRESSURE SYSTEM
APPROX 200 MILES EAST OF OCEAN CITY, MD AND WILL CONTINUE TO LIFT
NE OVERNIGHT. DRY AIRMASS WILL SLOWLY BUILD IN FROM THE WEST
OVERNIGHT...WHILE A STRONG NORTHERN STREAM SHORTWAVE CROSSES WELL
NORTH OF THE REGION...WITH A WEAK SHORTWAVE TROUGH CROSSING LATER
LATE TONIGHT THOUGH WITH LITTLE IMPACT ON SENSIBLE WX.
FORECAST TEMPS HAVE BEEN ON TRACK AND EXPECT LOWS OVERNIGHT MAINLY
IN THE LOW 40S INLAND COUNTIES BUT COULD SEE A FEW UPPER 30S,
WHILE COASTAL SECTIONS WILL SEE LOWS IN THE LOW/MID 40S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 315 PM FRIDAY...HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST SATURDAY WITH LIGHT AND VARIABLE WINDS THROUGHOUT THE
DAY. FLOW ALOFT WILL REMAIN WEST-NORTHWESTERLY. PWATS DROP TO
LESS THAN ONE HALF INCH WITH FORECAST SOUNDINGS INDICATING VERY
DRY MID/LOW LEVELS. TEMPS SATURDAY WILL BUILD INTO THE LOW TO MID
60S ACROSS INLAND LOCATIONS WITH MID/UPPER 50S EXPECTED ALONG AREA
BEACHES.
&&
.LONG TERM /TONIGHT THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...A SERIES OF WEAK SFC LOWS WILL MOVE THROUGH
THE GULF COAST REGION DURING THE LATTER HALF OF THE WEEKEND INTO
EARLY NEXT WEEK. THERE ARE STILL DIFFERENCES IN THE GUIDANCE WITH
HOW MUCH IF ANY PRECIPITATION MAKES IT NORTH INTO EASTERN NC WITH
THESE SYSTEMS. WILL CONT FORECAST OF 20-30% POPS SUNDAY AND 30-40%
MONDAY HIGHEST BOTH DAYS SOUTHERN ZONES. TEMPERATURES WILL BE NEAR
NORMAL SUNDAY WITH UPR 50S OBX TO MID 60S INLAND AREAS AND BELOW
NORMAL MONDAY WITH HIGHS IN THE LWR TO MID 50S.
THE INITIAL SOUTHERN STREAM SYSTEM MOVES OFF THE SE COAST LATE
MONDAY WITH A TRAILING NORTHERN STREAM TROF CROSSING THE AREA LATE
MONDAY NIGHT OR EARLY TUESDAY. WILL MAINTAIN SLIGHT CHANCE POPS
ALONG THE COAST MONDAY NIGHT FOR THE SECONDARY UPPER TROF BUT
SYSTEM WILL LACK AMS MSTR AND LIKELY MANY AREAS WILL RMN DRY.
TEMPS WILL CONT BELOW NORMAL ON TUE WITH HIGHS IN THE 50S.
HIGH PRESSURE WILL BUILD ACRS THE AREA THROUGH MIDWEEK WITH TEMPS
RETURNING TO NEAR NORMAL WEDNESDAY...MAINLY 60S FOR HIGHS...THEN
ABOVE NORMAL THURSDAY WITH HIGH TEMPS REACHING THE MID 70S ACRS
INLAND AREAS. WILL CONT FORECAST OF CHANCE POPS FOR BOTH THU AND
FRI UNTIL MODELS CAN COME INTO BETTER TIMING AGREEMENT OF THE COLD
FRONT. BELOW NORMAL TEMPS EXPECTED BEHIND THE FRONT FOR NEXT
WEEKEND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SATURDAY/...
AS OF 210 PM FRI...AN AREA OF STRATUS IS ADVECTING SOUTH ACROSS
THE AREA AND HAS REACHED THE HIGHWAY 70 CORRIDOR AFFECTING ALL TAF
SITES BUT OAJ TO THIS POINT, HOWEVER EXPECT IT TO REACH OAJ IN THE
NEXT HOUR OR TWO. VSBYS HAVE REMAINED GOOD BUT CIGS HAVE BEEN
GENERALLY AROUND 1-1.5K FT, OCCASIONALLY DROPPING JUST BELOW INTO
THE IFR RANGE.
HIGH CONFIDENCE THAT MVFR CIGS WILL PREVAIL AT THE TERMINALS EARLY
THIS MORNING BUT HAVE BELOW NORMAL CONFIDENCE FOR POTENTIAL IFR
CONDITIONS AS GUIDANCE NOT IN BEST AGREEMENT WITH AREAL EXTENT
AND HEIGHT OF THE STRATUS. NAM MOS IS UNDERDONE WITH THE STRATUS
WHILE THE GFS MOS APPEARS TOO PESSIMISTIC WITH IFR/LIFR ALREADY
IN PLACE WHERE CONDITIONS REMAIN MVFR. GENERALLY FOLLOWED UPSTREAM
TRENDS ALONG WITH THE GFS LAMP WHICH DOES BRING A PERIOD OF IFR TO
PGV AND ISO DURING THE PRE-DAWN HOURS AND KEEPS EWN AT MVFR. DID
BRING MVFR CIGS TO OAJ LOOKING AT TRENDS DESPITE MOST GUIDANCE
KEEPING CONDITIONS VFR FOR THE MOST PART. THE HRRR HOLDS ON TO THE
STRATUS MUCH LONGER THIS MORNING WHILE MOS GUIDANCE APPEARS TO
ERODE IT AROUND 12Z, WHICH IS LIKELY TOO QUICK AND HELD ONTO MVFR
CONDITIONS UNTIL 14-15Z, HOWEVER HRRR IS EVEN LATER THAN THIS,
ESPECIALLY ACROSS THE COASTAL PLAIN.
EXPECT LIGHT NORTHERLY WINDS THIS MORNING, BACKING TO SOUTHWEST
THIS AFTERNOON AND EVENING AS HIGH PRES SLIDES SOUTH ACROSS THE
AREA. PREDOMINANTLY VFR CONDITIONS EXPECTED THIS AFTERNOON AND
EVENING. FOG IS QUESTIONABLE TONIGHT. HYDROLAPSE RATES ARE
FAVORABLE FOR FOG DEVELOPMENT HOWEVER CROSSOVER TEMPS ARE NOT
EXPECTED TO BE REACHED AND MOS GUIDANCE KEEPING VFR CONDITIONS,
THEREFORE WILL NOT ADD FOG TO THE FORECAST AT THIS TIME.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...VFR CONDITIONS SHOULD DOMINATE THRU SAT NIGHT
AS HIGH PRES BUILDS INTO THE AREA WITH DRIER AIR OVERSPREADING
REGION. A SERIES OF WEAK LOWS DEVELOP TO THE S SUNDAY AND SLOWLY
LIFT NE MON. STILL UNCERTAINTY WITH HOW MUCH MOISTURE WILL STREAM
NORTH INTO EASTERN NC BUT THERE WILL BE A POTENTIAL FOR MVFR
CONDITIONS...ESPECIALLY SRN TIER THRU MON EVE.
&&
.MARINE...
SHORT TERM /THROUGH SATURDAY/...
AS OF 1020 PM FRIDAY...NO UPDATED NEEDED...CURRENT FORECAST IN
GOOD SHAPE. LATEST OBS SHOW NW WINDS 10-20KT AND SEAS 4-7FT NORTH
OF OCRACOKE AND 3-5FT SOUTH. SFC ANALYSIS CONTINUES TO SHOW THE
LOW PRESSURE SYS OFF THE DELMARVA COAST...AND WILL CONTINUE TO
LIFT NE AWAY FROM NC OVERNIGHT. COULD SEE GUSTS TO 25KT FOR THE
CENTRAL AND NORTHERN WATERS LATE TONIGHT AS LOW LIFTS NE. SEAS
WILL CONTINUE TO GRADUALLY SUBSIDE LATE TONIGHT INTO SATURDAY AS
HIGH PRESSURE BUILDS OVER THE WATERS FROM THE NORTHWEST. WINDS
REMAIN NORTHERLY EARLY SATURDAY THEN BACK WEST LATER IN THE DAY,
AND GENERALLY BELOW 15 KNOTS. SEAS SUBSIDE 2 TO 4 FT BY SATURDAY
AFTERNOON. SCA REMAINS IN EFFECT THROUGH LATE SAT MORNING NORTH OF
OCRACOKE.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...LIGHT WINDS EXPECTED SAT NIGHT INTO EARLY
SUNDAY WITH HIGH PRESSURE OVER THE AREA. AS A SERIES OF LOWS
DEVELOP TO THE S LATE SUNDAY AND MONDAY. NNE WINDS 10 TO 15 KTS
EXPECTED LATE SUNDAY AND INCREASING TO 15 TO 25 KTS SUNDAY NIGHT
AND MON. SEAS OF 3 TO 4 FT SUN EVENING WILL BUILD TO 6 TO 7 FT
MON. MODERATE NNE WINDS WILL MAINTAIN ELEVATED SEAS INTO TUESDAY
WITH NE FLOW FORECAST TO DIMINISH TO 10 TO 15 KT LATE. NE-E WINDS
DMNSH FURTHER TUE NIGHT INTO WED TO 10 KT OR LESS WITH SEAS
SUBSIDING TO 2 TO 4 FEET.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ150-
152-154.
&&
$$
SYNOPSIS...DAG
NEAR TERM...SK/BM
SHORT TERM...DAG
LONG TERM...JAC
AVIATION...JAC/SK
MARINE...JAC/CQD/DAG/BM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
129 AM CDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 129 AM CDT SAT MAR 21 2015
INCREASING ISENTROPIC LIFT AND INCREASING DIVERGENT FLOW ALOFT IN
THE RIGHT ENTRANCE REGION OF AN UPPER JET STREAK RESULTING IN
INCREASING CLOUDS ACROSS WEST AND CENTRAL NORTH DAKOTA. LATEST
RADAR IMAGERY MORE IN LINE WITH THE 00Z GFS WITH THE MAIN BAND OF
OVERRUNNING PRECIPITATION ACROSS THE NORTH BUT SOME ACTIVITY AS
FAR SOUTH AS I94. THUS KEPT IN WHAT THE INHERITED FORECAST HAD
WITH SOME MINOR TWEAKS. WENT LIKELY POPS ACROSS THE NORTH WHERE WE
EXPECT SOME LIGHT ACCUMULATING SNOW THIS MORNING.
UPDATE ISSUED AT 933 PM CDT FRI MAR 20 2015
LATEST HRRR RUNS SUGGEST THE PRECIP WILL TREND NORTH OF THE BORDER
DURING THE OVERNIGHT HOURS AND DEVELOP SOUTH INTO NORTH CENTRAL
NORTH DAKOTA BEFORE SUNRISE. NEW NAM RUN SIMILAR BUT A BIT FURTHER
WEST. EITHER ONE IS WELL WITHIN THE CURRENT FORECAST ENVELOPE AND
WILL NOT MAKE ANY CHANGES TO POPS FOR THIS REASON. TEMPERATURES
AND WINDS LOOK GOOD.
UPDATE ISSUED AT 639 PM CDT FRI MAR 20 2015
STRATUS CONTINUES TO SLIDE SOUTH ACROSS THE REGION. THE STRATUS
REPRESENTS THE BAROCLINIC ZONE THAT WILL BE THE KEY IN LIFTING THE
FLOW OVER THE COOL AIR AND GENERATE SNOW ACROSS THE NORTH AND EAST.
MADE SOME ADJUSTMENTS FOR TEMPERATURES AND CLOUDS. OTHERWISE SO FAR
FORECAST TRENDING OK.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
CURRENT SURFACE ANALYSIS PLACES LOW SETTLING DOWN THROUGH EASTERN
SOUTH DAKOTA WITH COLD FRONT SETTLING THROUGH SOUTHEAST INTO WEST
CENTRAL NORTH DAKOTA. CLEAR SKIES AND VERY WARM TEMPS ARE NOTED
AHEAD OF THE FRONT...WITH LOW CLOUDS AND CHILLY TEMPS BEHIND.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...CLOUD COVER WILL
CONTINUE TO SPREAD ACROSS THE AREA THROUGH THE AFTERNOON AS COOL
AIRMASS SPREADS IN. SOME LIGHT SNOW MAY START DEVELOPING LATE
TONIGHT OVER THE NORTHWEST AND SPREAD TO THE SOUTHEAST AS RIGHT
ENTRANCE REGION OF UPPER JET SLIDES THROUGH THE REGION WHILE SOME
MODEST ISENTROPIC LIFT DEVELOPS.
ON SATURDAY...CHANCES FOR SNOW CONTINUE PRIMARILY OVER THE NORTHERN
PORTIONS OF THE AREA IN MODEST ISENTROPIC LIFT AS AFOREMENTIONED JET
SLOWLY WORKS ITS WAY OFF TO THE EAST. SNOW AMOUNTS SHOULD REMAIN
LIGHT...MAINLY UNDER AN INCH. TEMPERATURES WILL AGAIN BE WARMEST OFF
TO THE SOUTHWEST WHILE COLD AIRMASS REMAINS OVER THE NORTH CENTRAL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 348 PM CDT FRI MAR 20 2015
SEVERAL ROUNDS OF RAIN AND ACCUMULATING SNOW SATURDAY THROUGH
WEDNESDAY.
THERE IS THE POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW SATURDAY
AFTERNOON THROUGH LATE SUNDAY NIGHT. ALL OF THE MAJOR OPERATIONAL
MODELS (GFS/ECMWF/GEM/NAM/SREF) CONTINUE TO INDICATE ACCUMULATING
SNOW NORTH AND EAST OF THE MISSOURI RIVER SATURDAY THROUGH SUNDAY.
A RATHER PRONOUNCED BAROCLINIC ZONE WILL BISECT NORTH DAKOTA.
NORTH AND EAST OF THE MISSOURI RIVER TEMPERATURES ARE EXPECTED TO
REMAIN NEAR OR BELOW FREEZING. WHILE TEMPERATURES SOUTH AND WEST
OF THE RIVER SHOULD CLIMB INTO THE 40S AND 50S. UPSLOPE
FLOW...LEE CYCLOGENESIS AND A FAVORABLE CURVED UPPER LEVEL
JET...SHOULD PRODUCE WIDESPREAD 2 TO 4 INCHES ACROSS THE NORTH
AND EAST.
THE NEXT SYSTEM COULD IMPACT THE REGION MONDAY NIGHT THROUGH
WEDNESDAY. THERE IS STILL A LOT OF UNCERTAINTY IN THE EXACT TRACK
OF THIS SYSTEM. OVER THE PAST TWO MODEL RUNS THE GFS HAS
COMPLETELY FLIP FLOPPED FROM A NORTHERN SOLUTION TO A SOUTHERN
SOLUTION. THE ECMWF REMAINS FAIRLY CONSISTENT WITH A MIDDLE OF THE
ROAD SOLUTION. THERE APPEARS TO BE A GREAT DEAL OF WARM AIR WRAPPED
UP AHEAD OF THIS SYSTEM. THEREFORE...INITIAL PRECIPITATION MAY BE
ALL RAIN BEFORE CHANGING OVER TO SNOW AS COLD AIR MOVES IN BEHIND
THE LOW. TEMPERATURES WILL VARY GREATLY BASED ON THE EXACT
TRACK OF THE LOW PRESSURE CENTER. THEREFORE...WHILE HEAVY
SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG
FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROWEL SET UP
ACROSS THE REGION...TOO MUCH UNCERTAINTY REMAINS TO NAIL DOWN
SPECIFIC LOCATIONS AND SNOWFALL AMOUNTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 129 AM CDT SAT MAR 21 2015
MVFR-IFR CONDITIONS ARE EXPECTED TO PREVAIL FROM KISN-KMOT-KDIK-
KBIS WHERE EASTERLY UPSLOPE FLOW WILL MAINTAIN A STRATUS DECK. KJMS
SHOULD REMAIN VFR THROUGH THE PERIOD. SNOW WILL DEVELOP ACROSS THE
NORTH...KISN-KMOT...WHERE SUB-IFR CONDITIONS ARE POSSIBLE. VLIFR-
LIFR AT KDIK WILL ALSO PERSIST UNTIL AROUND MID SATURDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JJS
LONG TERM...AJ
AVIATION...NH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
527 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS CONTINUE TO IMPACT THE
AIRSPACE EARLY THIS MORNING. RADAR SHOWS AREA OF -RASN CROSSING
WRN NY AND SHOULD NOT AFFECT TAFS. UPDATED MDT/IPT WHICH DROPPED
INTO IFR CAT (CIGS). LNS OB NOT AVAILABLE IN SYSTEM BUT CALL DIAL
UP. LOOK FOR IMPROVING CONDS DURING THE DAYLIGHT HOURS AS WSW
WINDS BEGIN TO INCREASE AHEAD OF A COLD FRONT APPROACHING FROM THE
NW. THE FROPA WILL OCCUR FROM NW TO SE THIS AFTN-EVE AND MAY BE
ACCOMPANIED BY A BRIEF PD OF -RA. A RETURN TO VFR IS PROJECTED FOR
MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
355 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
UNDER A NARROW SFC HIGH...VERY LIGHT/CALM WINDS AND RESIDUAL LLVL
MSTR TRAPPED BLO INVERSION ARE SUPPORTING WIDESPREAD LOW CIGS AND
REDUCED VSBYS IN THE MVFR TO LIFR RANGE. LOOK FOR IMPROVING CONDS
DURING THE DAYLIGHT HOURS AS WSW WINDS BEGIN TO INCREASE AHEAD OF
A COLD FRONT APPROACHING FROM THE NW. THE FROPA WILL OCCUR FROM
NW TO SE THIS AFTN-EVE AND MAY BE ACCOMPANIED BY A BRIEF PD OF
-RA. A RETURN TO VFR IS PROJECTED FOR MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
214 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE ACROSS THE LAUREL
HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT.
NOTHING MORE THAN SOME VERY PATCHY AND LIGHT DRIZZLE WILL OCCUR.
TEMPS WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST A DEG OR 2
IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME PARTIAL
CLEARING OCCURS.
FURTHERMORE...PARTIAL CLEARING IN ANY LOCATION COULD ALLOW
READINGS TO FALL JUST BLW FREEZING AND CREATE SOME ICY SPOTS ON
UNTREATED ROADS. ANY BREAKS IN THE CLOUD COVER COULD ALSO CREATE
MORE IN THE WAY OF PATCHY DENSE FOG.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR
TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY.
GEFS AND 18Z OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS ACROSS
THE NW MTNS AS FRONT COMES THRU. EVEN THE LOWER SUSQ VALLEY COULD
SEE A SHOWER IN SPOTS WITH THE LATE DAY FROPA.
A SURGE OF MILDER AIR AHEAD OF FRONT WILL PUSH READINGS TO NEAR
SEASONAL NORMS...DESPITE A GOOD DEAL OF CLOUDINESS. HIGHS SHOULD
RANGE FROM THE MID 40S TO LOWER 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SAT NIGHT INTO
MIDWEEK...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT WILL
BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO
THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE
NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
UNDER A NARROW SFC HIGH...VERY LIGHT/CALM WINDS AND RESIDUAL LLVL
MSTR TRAPPED BLO INVERSION ARE SUPPORTING WIDESPREAD LOW CIGS AND
REDUCED VSBYS IN THE MVFR TO LIFR RANGE. LOOK FOR IMPROVING CONDS
DURING THE DAYLIGHT HOURS AS WSW WINDS BEGIN TO INCREASE AHEAD OF
A COLD FRONT APPROACHING FROM THE NW. THE FROPA WILL OCCUR FROM
NW TO SE THIS AFTN-EVE AND MAY BE ACCOMPANIED BY A BRIEF PD OF
-RA. A RETURN TO VFR IS PROJECTED FOR MOST SITES BY 00Z SUN.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
131 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON LATE TODAY PASSAGE LATE THIS AFTERNOON AND THIS EVENING.
THIS FRONT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL
TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE ACROSS THE LAUREL
HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT.
NOTHING MORE THAN SOME VERY PATCHY AND LIGHT DRIZZLE WILL OCCUR.
TEMPS WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST A DEG OR 2
IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME PARTIAL
CLEARING OCCURS.
FURTHERMORE...PARTIAL CLEARING IN ANY LOCATION COULD ALLOW
READINGS TO FALL JUST BLW FREEZING AND CREATE SOME ICY SPOTS ON
UNTREATED ROADS. ANY BREAKS IN THE CLOUD COVER COULD ALSO CREATE
MORE IN THE WAY OF PATCHY DENSE FOG.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR
TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY.
GEFS AND 18Z OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS ACROSS
THE NW MTNS AS FRONT COMES THRU. EVEN THE LOWER SUSQ VALLEY COULD
SEE A SHOWER IN SPOTS WITH THE LATE DAY FROPA.
A SURGE OF MILDER AIR AHEAD OF FRONT WILL PUSH READINGS TO NEAR
SEASONAL NORMS...DESPITE A GOOD DEAL OF CLOUDINESS. HIGHS SHOULD
RANGE FROM THE MID 40S TO LOWER 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SAT NIGHT INTO
MIDWEEK...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT WILL
BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO
THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE
NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
BEEN UPDATING TAFS AS NEEDED THIS EVENING.
EARLIER DISCUSSION BELOW.
WIDESPREAD IFR AND MVFR CONDITIONS EXPECTED OVERNIGHT INTO
SATURDAY MORNING.
CONDITIONS WILL SLOWLY IMPROVE LATER SATURDAY...AS WINDS PICK
UP FROM THE SW.
A COLD FRONT MOVES IN LATE SAT...A FEW RAIN OR SNOW SHOWERS
POSSIBLE ACROSS THE NORTH.
DRY AIR COMING IN SUNDAY WILL PREVAIL INTO TUE...AS HIGH
PRESSURE BUILDS EASTWARD.
PERHAPS A FEW RAIN SHOWERS ON WED.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...MAINLY VFR WITH SCATTERED RAIN SHOWERS.
&&
.CLIMATE...
SPRING OFFICIALLY BEGINS AT 645 PM EDT/2245 UTC THIS EVENING.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...RXR
AVIATION...MARTIN
CLIMATE...
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1201 AM CDT SAT MAR 21 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...BRO AND HRL AT LIFR WITH OVC LOW CEILINGS WHILE MFE
AWAY FROM THE COAST REMAINS VFR. MARINE AND COASTAL FOG WILL
COMPLICATE AVIATION CONDITIONS AGAIN THIS TAF CYCLE...ALONG WITH
LOW CIGS. LIGHT SOUTHEAST WINDS WILL PREVAIL THE REST OF THE NIGHT
WHILE DEW POINTS ARE IN THE MUGGY UPPER 60S TO LOWER 70S. WINDS
WILL ATTEMPT TO SWITCH TO NORTH SOMETIME DURING THE DAY AS A COLD
FRONT MEANDERS SOUTH INTO THE AREA...BUT WITH HIGH RAIN CHANCES
TODAY...LOW CEILINGS AND REDUCED VISIBILITY SHOULD KEEP THE TAFS
IFR.
&&
.PREV DISCUSSION... /ISSUED 948 PM CDT FRI MAR 20 2015/
DISCUSSION...THE COMBINATION OF SURFACE OBS AND WEB CAM IMAGES
FROM SPI INDICATES THAT VSBYS ARE FALLING STEADILY DUE TO THE WAA
COMING IN FROM THE SE OVER FAIRLY COOLER SURF AND BAY WATER TEMPS
IN THE MID 60S. SO WILL POST UP A DENSE FOG ADVISORY FOR THE
LAGUNA MADRE...LOWER TX GULF WATERS OUT TO 20 NM OFFSHORE AND FOR
COASTAL WILLACY AND COASTAL CAMERON COUNTIES THROUGH 7 AM
TOMORROW.
CONCERNING THE MAIN SHORT TERM THREAT...HEAVY RAINFALL...THE SHORT
RANGE HRRR GUIDANCE MAINTAINS THE THREAT OF LOCALLY HEAVY RAINFALL
OVER PORTIONS OF THE NORTHERN AND WESTERN COUNTIES THROUGHOUT LATE
TONIGHT INTO SATURDAY MORNING. THE RAINFALL WILL EXPAND FURTHER
EAST AND SOUTH THROUGHOUT SATURDAY AS THE 500 MB CLOSED LOW TO OUR
WEST OPENS UP AND PUSHES EAST ACROSS TX SAT AND SAT NIGHT. SPC
MAINTAINS A MARGINAL THREAT FOR SVR T-STORMS THROUGHOUT SATURDAY
AS THE PWATS...CAPE VALUES AND BULK SHEAR INCREASE OVER THE
REGION. THE MAIN THREAT FROM ANY OF THE STRONGER CONVECTION THAT
FORMS WILL BE MAINLY FROM GUSTY WINDS AND POSSIBLE SEVERE HAIL.
FOR NOW WILL NOT MAKE ANY OTHER MAJOR CHANGES TO THE ONGOING
FORECAST WORDING. THE CURRENT FFA IN EFFECT MAY NEED TO BE
ADJUSTED OR POSSIBLY EXPANDED THROUGH THE OVERNIGHT HOURS TO
ACCOUNT FOR THE NEAR TERM CONV TRENDS OVERNIGHT.
PREV DISCUSSION... /ISSUED 755 PM CDT FRI MAR 20 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...A FAIRLY COMPLEX AVIATION SITUATION IS SETTING UP
OVER THE NEXT 24 HOURS AS THE DEEP 500 MB TROUGH AXIS TO THE WEST
OF SOUTH TX DIGS EAST. THE APPROACH OF THIS TROUGH AXIS WILL
STEADILY DEEPEN THE PWAT AND CAPE VALUES THROUGHOUT TONIGHT AND
SATURDAY LIKELY RESULTING IN INCREASING CONV COVERAGE ACROSS THE
RGV AIPPORTS DURING THE LATTER HALF OF THE CURRENT TAF SETS AS THE
UPPER LEVEL SUPPORT INCREASES. THIS WILL RESULT IN PERIODS OF
VFR/MVFR CONDITIONS WITH PERIODS OF IFR CEILINGS/VSBYS DUE TO
PERIODS OF THE STRONGER CONV MAINLY AFTER 12Z SAT. IN THE EARLIER
TAF PERIODS EXPECT THE LOW LEVEL WAA MOVING OVER THE COOLER
NEARSHORE WATERS NEAR SPI TO ALLOW AREAS OF LOW CLOUDS AND VSBYS
TO REFORM AND ADVECT WESTWARDS LATER TONIGHT REUSLTING IN
IFR/LIFR CEILINGS FOR ALL THREE RGV AIRPORTS.
PREV DISCUSSION... /ISSUED 323 PM CDT FRI MAR 20 2015/
SHORT TERM /NOW THROUGH SATURDAY NIGHT/...LATEST WATER VAPOR
IMAGERY SHOWS A 500MB LOW OVER BAJA CALIFORNIA WITH ABUNDANT PACIFIC
MOISTURE STREAMING ACROSS THE AREA FROM THE SOUTHWEST. BRO RADAR
SHOWS SOME WEAK ECHOS ACROSS THE RIO GRANDE RIVER...SOUTH OF ZAPATA.
CURRENT SURFACE ANALYSIS SHOWS A WEAK COLD FRONT ACROSS THE HILL
COUNTRY THIS AFTERNOON. SURFACE OBSERVATIONS AND WEBCAMS ON SOUTH
PADRE ISLAND INDICATE LIGHT FOG/HAZE ALONG THE LOWER TEXAS...WITH
VISIBILITIES RANGING BETWEEN 5 TO 6 MILES. HOWEVER...THICKER SEA FOG
CONTINUES OVER THE NEAR SHORE GULF WATERS 0 TO 20 NM EAST OF PADRE
ISLAND.
TONIGHT...THE CUT OFF LOW WILL EJECT SLOWLY EAST INTO NORTHWEST
MEXICO. DEEP LAYERED SOUTHWEST FLOW WILL CONTINUE TO ADVECT GULF AND
PACIFIC MOISTURE THE REGION. THE WEAK COLD FRONT WILL SLOWLY MOVE
INTO THE RANCHLANDS LATER TONIGHT. THE WEAK SURFACE FRONT COMBINED
WITH ENERGY ALOFT WILL PROVIDE THE OPPORTUNITY FOR HEAVY RAIN...
ESPECIALLY ACROSS THE NORTHERN RANCHLANDS...FOR TONIGHT INTO
SATURDAY. THE LATEST WPC QPF VALUES PAINTS BETWEEN 1 TO 3
INCHES...LOCALLY UP TO 4 INCHES...ACROSS THE WESTERN PORTIONS OF
DEEP SOUTH TEXAS. DUE TO RECENT RAINS AND EXPECTED HEAVY RAINS...A
FLASH FLOOD WATCH HAS BEEN ISSUED FOR BROOKS...JIM HOGG AND ZAPATA
COUNTIES BEGINNING THIS EVENING AT 7 PM.
RAINFALL WILL INCREASE ACROSS THE WESTERN BRUSH COUNTRY INTO THE
UPPER VALLEY TONIGHT. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE ACROSS THE LOWER VALLEY..ESPECIALLY AFTER MIDNIGHT.
FOG WILL BE A CONCERN AGAIN TONIGHT ALONG THE COAST AND ACROSS THE
NEAR SHORE GULF WATERS TONIGHT DUE TO LIGHT WINDS AND HIGH
DEWPOINTS. AREAS OF FOG...LOCALLY DENSE FOG NEAR THE
COAST...EXPECTED TONIGHT. LOW TEMPERATURES TONIGHT WILL BE NEAR
NORMAL...IN THE MID 60S...UNDER CLOUDY SKIES.
SATURDAY AND SATURDAY NIGHT...THE 500MB LOW MOVES TOWARDS THE BIG
BEND REGION SATURDAY AND INTO NORTHERN TEXAS BY SATURDAY NIGHT.
SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS DEEP SOUTH TEXAS WITH
THE BEST LIFT OCCURRING SATURDAY INTO SATURDAY NIGHT. SPC SHOWS A
MARGINAL RISK OF SEVERE THUNDERSTORMS...GENERALLY ALONG AND EAST OF
I-69C/HWY 281 SATURDAY INTO SATURDAY NIGHT. THE MAIN IMPACTS WITH
THIS ACTIVITY WILL BE HEAVY RAIN...GUSTY WINDS AND SMALL HAIL...DIME
SIZE OR LESS. THE WEAK FRONT DRAPED ACROSS THE REGION SATURDAY NIGHT
WILL RESULT IN VERY LIGHT WINDS. THIS WILL RESULT IN AREAS OF
FOG...SOME LOCALLY DENSE...ALONG THE COAST. HIGH TEMPERATURES
SATURDAY WILL BE IN THE 70S WITH UPPER 60S ALONG THE COAST.
OVERNIGHT LOW TEMPERATURES SATURDAY NIGHT WILL BE IN THE UPPER 50S
ACROSS THE RANCHLANDS TO THE MID 60S NEAR THE COAST.
LONG TERM /SUNDAY THROUGH FRIDAY/...DRIER AIR WILL MOVE INTO
SOUTHWEST TEXAS SUNDAY BRINGING AN END TO THE RAIN CHANCES ACROSS
THE CWA AS THE 500MB SHORTWAVE TROUGH ACROSS TEXAS MOVES EASTWARD
AND THE SOUTHWEST FLOW ALOFT VEERS TO THE WEST AND NORTHWEST
PROVIDING SUBSIDENCE ACROSS THE WESTERN HALF OF THE STATE. AT THE
SURFACE...THE WEAK COLD FRONT WILL MOVE THROUGH THE RIO GRANDE
VALLEY SUN AFTERNOON. WARM AND RELATIVELY DRY CONDITIONS SHOULD
PREVAIL ACROSS SOUTH TX MONDAY THROUGH WEDNESDAY WITH A NEARLY
ZONAL FLOW PREVAILING ACROSS THE SOUTHERN UNITED STATES. A 500MB
TROUGH IS EXPECTED TO DEVELOP ACROSS THE CENTRAL U.S. AND A 500MB
TROUGH/LOW IS ALSO EXPECTED TO DEVELOP ACROSS BAJA CALIFORNIA
WEDNESDAY INTO THURSDAY. LOW TO MID LEVEL MOISTURE IS PROGGED TO
INCREASE ACROSS SOUTH TX WEDNESDAY AND THURSDAY BEFORE A COLD
FRONT MOVES THROUGH THE RIO GRANDE VALLEY THURS NIGHT INTO FRI
MORNING. THERE ARE STILL SOME DIFFERENCES BETWEEN THE ECMWF AND
THE GFS ON THE TIMING OF THIS FRONT. WILL MENTION A SLIGHT CHANCE
TO CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY AND A CHANCE OF
SHOWERS FRIDAY AS MOISTURE POOLS ALONG AND AHEAD OF THE FRONT
THROUGH THE REST OF THE FORECAST PERIOD.
MARINE...
NOW THROUGH SATURDAY NIGHT...SHOWERS AND THUNDERSTORMS POSSIBLE
SATURDAY AND SATURDAY NIGHT AS A WEAK COLD FRONT APPROACHES THE
LOWER TEXAS COASTAL WATERS. LIGHT TO MODERATE SOUTHEAST WINDS AND
LOW SEAS WILL PREVAIL THROUGH THE FORECAST PERIOD.
SUNDAY THROUGH WEDNESDAY...LIGHT SOUTH WINDS WILL PREVAIL ACROSS
THE COASTAL WATERS SUNDAY BEFORE A WEAK COLD FRONT MOVES OFFSHORE
THE LOWER TEXAS COAST SUN AFTERNOON. WINDS WILL SHIFT TO THE
NORTHWEST SUN AFTERNOON BUT BECOME LIGHT AND VARIABLE SUN NIGHT.
THE WINDS WILL INCREASE FROM THE NORTH AS HIGH PRESSURE FINALLY
BUILDS INTO THE WESTERN GULF OF MEXICO MONDAY IN THE WAKE OF THE
FRONTAL SYSTEM OVER EAST TX SUNDAY MOVING EASTWARD MONDAY. LIGHT
TO MODERATE NORTH WINDS MONDAY WILL VEER TO THE SOUTHEAST TUESDAY
AS THE SURFACE RIDGE MOVES QUICKLY EASTWARD. LIGHT TO MODERATE
SOUTHEAST WINDS SHOULD PREVAIL ACROSS THE LOWER TX COAST TUESDAY
INTO WEDNESDAY.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR TXZ248>250.
DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR TXZ256-257.
GM...DENSE FOG ADVISORY UNTIL 7 AM CDT SATURDAY FOR GMZ130-132-135-
150-155.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54/55
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
950 AM EDT SAT MAR 21 2015
.DISCUSSION... A REVIEW OF THE MORNING SOUNDING PARAMETERS INDICATE
ONLY A MARGINALLY FAVORABLE SETUP FOR DEVELOPMENT OF AFTN SHOWERS.
MID LEVEL CAPPING PRESENT EARLY FRIDAY HAS ERODED SOME...HOWEVER H5
TEMPS REMAIN A RELATIVELY WARM -7C. IN ADDITION...THERE HAS BEEN
SOME DRYING OF THE COLUMN TO AROUND 1.4 IN PWAT WITH DEEPER LAYER
WLY/NW STEERING. CONSIDERING ALL FACTORS WHILE GIVEN LIKELIHOOD OF
ECSB BOUNDARY AND MID TO LATE AFTERNOON COLLISIONS WL KEEP AN ISOLD
MENTION OF SHOWERS IN THE AFTERNOON FORECAST WHILE EXPANDING THE
MENTION TO INCLUDE THE TREASURE CST AND LAKE OKEE AREAS AS INDICATED
BY LTST 2KM HRRR WHERE CVG IS THE HIGHEST AT MID TO LATE AFTN.
FORECAST UPDATE HAS BEEN SENT TO REMOVE THE EARLIER DENSE FOG
ADVISORY AND REVISING THE PRECIP CVG AS WELL.
CURRENTLY...(FROM PREV DISC) A FRONTAL BOUNDARY TRAILED FROM LOW
PRESSURE ALONG THE CAROLINA COAST WITH THE SOUTHERN END BECOMING ILL
DEFINED OVER EAST CENTRAL FLORIDA. SURFACE WIND AND THETA E FIELDS
FROM THE GFS SUGGEST THAT THE TAIL OF THE FRONT ACTUALLY HOOKS BACK
NORTHWARD ALONG THE COAST FROM ABOUT BREVARD TO VOLUSIA.
THE CHANCE FOR CONVECTION LOOKS LOW AGAIN AND MAINLY CONFINED TO SEA
BREEZE INTERACTIONS WHERE THE REMNANT MOISTURE FROM THE
AFOREMENTIONED SURFACE BOUNDARY EXISTS. THE GFS SEEMS TO HAVE THE
BEST SOLUTION...THOUGH THE LOCAL WRF WHICH IS BASED OFF THE
NAM...GENERATES LITTLE PRECIP. WE WILL HAVE TO SEE BUT OVERALL THE
NAM LOOKS TOO DRY.
TEMPS WILL RISE QUICKLY INTO THE MID/UPPER 80S AGAIN EXCEPT FOR SOME
LOWER 80S RIGHT ALONG THE COAST.
&&
.AVIATION...AFT 14Z VFR IS EXPECTED EXCEPT MAYBE RIGHT ALONG THE
COAST FROM KDAB-KTIX WHERE SOME STRATUS MAY LINGER A LITTLE LONGER.
SMALL SHOWER CHANCES AREAWIDE THIS AFTERNOON WITH AFFECTED LOCATIONS
POSSIBLY SEEING A PERIOD OF MVFR CONDS. EXPECT PATCHY FOG LATE
TONIGHT...THOUGH EXTENSIVE MID/HIGH CLOUDS SHOULD BE MORE OF A
LIMITING FACTOR.
&&
.MARINE... TODAY-TONIGHT...WINDS LOOK VARIABLE 5 KNOTS THIS MORNING
THEN WITH THE SEA BREEZE CIRCULATION THEY WILL BECOME ONSHORE 5-10
KNOTS IN THE AFTERNOON. THE MODELS THEN SHOW SURFACE HIGH PRESSURE
SLIDING SEAWARD TONIGHT WITH WINDS TURNING SOUTHEAST TO SOUTH 8-12
KNOTS. SOME SHOWERS WILL MOVE OFF THE BARRIER ISLANDS AND OVER THE
ADJACENT ATLC FROM LATE AFTN INTO THE EARLY EVENING
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
JP/AC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1027 AM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1027 AM EDT SAT MAR 21 2015
OVERALL...JUST MINOR TWEAKS TO THE GOING FORECAST...LARGELY TO THE
LAKE EFFECT POPS/CLOUDS TO MATCH UP WITH THE ONGOING SNOW SHOWERS.
WITH RAP ANALYZED 850MB TEMPS AROUND -16C OVER LAKE
SUPERIOR...THERE IS PLENTY OF OVER THE LAKE INSTABILITY TO LEAD TO
LAKE EFFECT. BUT THE COMBINATION OF THE REMAINING ICE AND LIMITED
MOISTURE HAS IMPACTED THE COVERAGE SO FAR THIS MORNING UNDER
GENERALLY NORTHERLY WINDS. THUS...AREAS OVER THE KEWEENAW PENINSULA
AND TOWARDS LUCE COUNTY HAVE BEEN MOSTLY SUNNY DUE TO THE UPSTREAM
ICE COVER. HAVE TRIMMED BACK POPS/CLOUDS FOR THOSE AREAS THROUGH
THE MORNING AND EARLY AFTERNOON UNTIL 950-925MB WINDS BEGIN TO BACK
TOWARDS 290-300 DEGREES AROUND 18Z. THEN TRENDED POPS UP DOWNSTREAM
OF THE ICE FREE AREAS OF LAKE SUPERIOR WITH THAT WIND DIRECTION.
OTHERWISE...TRENDED POPS UP TO HIGH CHANCE VALUES FOR THE NORTH
CENTRAL THIS MORNING WITH THE OPEN WATER SOUTHEAST OF THE KEWEENAW
PENINSULA AND FAVORED WIND DIRECTION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT SAT MAR 21 2015
SPRING IN UPPER MI USUALLY MEANS MORE SNOW...SO HERE WE GO. THE CWA
IS CURRENTLY IN BETWEEN WEATHER MAKERS. THE INITIAL LOW AND
ASSOCIATED COLD FRONT THAT BROUGH A MIXED BAG OF PRECIP ARE EXITING
FAR E UPPER MI/LAKE HURON. THE SECOND WEATHER MAKER IS IN THE FORM
OF COOLER AIR THAT WILL BE PUSHING IN ON FAVORABLE N-NW WINDS LATER
THIS MORNING. HOWEVER...A CLEARING SKY HAS BEEN THE RESULT OVER MUCH
OF THE W HALF OF UPPER MI AS DRY AIR LOOKS TO BE STEADY FORCE
UPSTREAM. THIS HAS BEEN MORE TEMPORARY OVER THE KEWEENAW AS LAKE
EFFECT CLOUDS DEVELOP IN THE OPEN WATERS TO THE N. ICE
COVER...ALTHOUGH THIN...LOOKS EXPANSIVE N OF SLEEPING AND MISERY
BAYS /NE OF ONTONAGON/. THIS WILL INHIBIT SOME OF THE LES THAT IS
EXPECTED TO DEVELOP LATER TODAY AS 850MB TEMPS FALL FROM AN AVERAGE -
10C EARLY THIS MORNING TO -13C BY THE END OF THE DAY...AND -16C BY
06Z SUNDAY. NOT EXPECTING MUCH SNOW...WHICH WILL BE ALONG THE
TRADITIONAL N-NW LES AREAS. WITH THE COOLER AIR SWEEPING IN..EXPECT
HIGHS ONLY IN THE 20S OR 30S. NORMAL HIGHS THIS TIME OF YEAR ARE IN
THE MID TO UPPER 30S. THE SFC HIGH OVER MUCH OF CENTRAL CANADA WILL
CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES...WITH THE N FLOW
CONTINUING...BUT LIGHTER. THIS WILL KEEP WINDS AROUND 5KTS THROUGH
THE OVERNIGHT HOURS. LOWERED THE FCST SLIGHTLY FOR TONIGHT...WITH
THE COLDEST AIR SLOWLY EXITING TO THE E...AND LIGHT WINDS AS THE SFC
HIGH SHIFTS MORE OVERHEAD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 536 AM EDT SAT MAR 21 2015
THRU LATE MONTH AND INTO EARLY APR...IT APPEARS PATTERN WILL
CONTINUE TO FAVOR RIDGING OVER WRN NAMERICA AND TROFFING OVER ERN
NAMERICA. AS A RESULT...WHILE THERE WILL BE OCCASIONAL DAYS OF ABOVE
NORMAL TEMPS FOR UPPER MI...THE PATTERN ON THE WHOLE WILL SUPPORT
NORMAL TO BELOW NORMAL TEMPS WITH BLO NORMAL LIKELY THE MORE COMMON
OUTCOME FOR THE MAJORITY OF DAYS. THE MJO IS CURRENTLY VERY
STRONG...AND WHILE IT IS FCST TO WEAKEN...THE PHASE OF THE MJO WILL
FAVOR BLO NORMAL TEMPS FOR THE GREAT LAKES LATE THIS MONTH INTO
EARLY APR...FURTHER SUPPORTING THE COOL INDICATIONS FROM OTHER
GUIDANCE. WITH NW FLOW MOSTLY PREVAILING...PCPN OVERALL WILL ALSO
LIKELY BE BLO NORMAL FOR AT LEAST THE NEXT 2-3 WEEKS...CONTINUING
THE DRY SYNOPTIC TREND NOTED FOR THE YEAR SO FAR (NEARLY ALL OF
UPPER MI IS RUNNING BLO NORMAL PCPN FOR THE YEAR...AND MUCH OF WI
INTO PORTIONS OF SCNTRL AND WRN UPPER MI ARE JUST 25-50PCT OF NORMAL
PCPN). WHILE BLO NORMAL PCPN WILL BE FAVORED OVERALL...THERE WILL BE
ONE SYSTEM AT THE MIDDLE OF NEXT WEEK THAT SHOULD PROVIDE WIDESPREAD
MDT PCPN...A RARE EVENT FOR UPPER MI SO FAR THIS YEAR. MORE ON THAT
LATER.
BEGINNING SUN...WITH 850MB TEMPS AS LOW AS -20C OVER ERN LAKE
SUPERIOR...EXPECT NW FLOW LES INTO AREAS EAST OF MARQUETTE. THE
LARGER OPEN WATER AREA TO THE LEE OF THE KEWEENAW WILL BE A PLUS FOR
LES INTO ALGER COUNTY. ALTHOUGH FCST SOUNDINGS SHOW INVERSIONS AT
AROUND 4KFT...THE DGZ OCCUPIES MUCH OF THE CONVECTIVE LAYER...AND
THAT MAY HELP FLUFF UP AN INCH OR 2 OF SNOW ACCUMULATION IF SHSN ARE
PERSISTENT AT ANY ONE LOCATION SUN MORNING. WITH MUCH MORE
PRONOUNCED ANTICYCLONIC FLOW INTO WRN LAKE SUPERIOR ASSOCIATED WITH
SFC HIGH PRES RIDGE NOSING INTO THE UPPER LAKES AND WITH 850MB TEMPS
ONLY AROUND -13C AT 12Z SUN...THERE MAY NOT BE MUCH MORE THAN
FLURRIES OFF WRN LAKE SUPERIOR DESPITE CONSIDERABLY MORE OPEN WATER
THAN OVER ERN LAKE SUPERIOR. MODERATION OF 850MB TEMPS SUN AFTN
WORKING IN CONCERT WITH THE DISRUPTIVE EFFECT OF SPRINGTIME SOLAR
INSOLATION ON LES WILL LIKELY SPELL AN END TO LES IN THE AFTN OVER
THE E OR AT LEAST A DIMINISHING TO FLURRIES. EXPECT HIGHS IN THE 20S
AND 30S...WARMEST TOWARD THE MI/WI BORDER.
SUN NIGHT/MON LOOK QUIET WITH SFC HIGH PRES IN CONTROL. AS WAS THE
CASE YESTERDAY...MODELS SHOWS A SHORTWAVE MOVING FROM THE DAKOTAS
INTO THE WRN GREAT LAKES WITH ASSOCIATED PCPN SPREADING ACROSS MN/WI
SUN NIGHT. GEM AND ECMWF BRING PCPN VERY NEAR THE WI/MI BORDER.
GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES AND DRY AIR EMANATING
FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF
HERE...A DRY FCST IS THE WAY TO GO. SUN NIGHT SHOULD BE QUITE
CHILLY...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH CLOUDS WILL BE
THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT
TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO.
MON NIGHT/TUE...ANOTHER WEAKENING SHORTWAVE WILL TRACK ESE INTO THE
WRN LAKES MON NIGHT. AT THE SAME TIME...UPPER RIDGE WILL BE MOVING
INTO THE UPPER MISSISSIPPI VALLEY/WRN GREAT LAKES DOWNSTREAM OF
FALLING HEIGHTS/STRONGER WAVE SHIFTING ACROSS THE NRN ROCKIES INTO
THE NRN PLAINS. THIS WILL SUPPORT LARGE SFC HIGH PRES OVER THE GREAT
LAKES REGION MON NIGHT THAT WILL DRIFT TOWARD NEW ENGLAND TUE. AS A
RESULT...ANY PCPN ASSOCIATED WITH WEAKENING SHORTWAVE SHOULD
DISSIPATE WITH TIME BEFORE REACHING UPPER MI.
NOW ONTO THE MAIN FEATURE FOR THIS FCST PERIOD. COMPLEX OF SHORTWAVE
ENERGY MOVING ONSHORE OVER THE PACIFIC NW SUN NIGHT/MON MORNING
WILL REACH THE WRN PLAINS TUE AND THEN MOVE ACROSS THE WRN GREAT
LAKES WED. 00Z MODEL GUIDANCE HAS OVERALL TRENDED MORE ROBUST WITH
THE MAIN SHORTWAVE ENERGY REACHING NEBRASKA TUE AND THEN WI/MI WED
MORNING. COMPLICATING FACTOR IS ADDITIONAL SHORTWAVE ENERGY MOVING
MORE SLOWLY ACROSS THE DAKOTAS AND HOW IT AFFECTS/INTERACTS WITH THE
MAIN WAVE. THIS WILL NO DOUBT CAUSE FLUCTUATIONS IN THE UPCOMING
MODEL RUNS...AND IT PROBABLY WON`T BE CLARIFIED UNTIL WE GET INTO
THE SHORT RANGE WITH THIS SYSTEM. THAT SAID...AS MENTIONED...MODELS
FOR NOW HAVE OVERALL TRENDED STRONGER WITH THE MAIN WAVE WHICH TAKES
ON A BRIEF NEGATIVE TILT AT AN OPTIMUM TIME AS IT SWINGS INTO THE
WRN GREAT LAKES. LOOKS LIKE QUITE THE DYNAMIC SYSTEM WITH 00Z
GFS/ECMWF SHOWING CENTER OF IMPRESSIVE 12HR 500MB HEIGHT FALLS OF
170-200M TRACKING ACROSS WI INTO ERN UPPER MI/STRAITS AREA. ALSO
NOTED IS STRONG DIFFLUENCE IN LEFT EXIT OF 100+KT UPPER JET AIMING
INTO LWR MI. ISENTROPIC ANALYSIS SHOWS MIXING RATIOS OF 3 TO 3.5G/KG
AVBL AROUND 750MB. WITH WHAT LOOKS LIKE ABOUT 9HRS OF GOOD ASCENT...
THIS WOULD SUGGEST THE POTENTIAL FOR ROUGHLY 5 INCHES OF SNOW. GIVEN
THE STRONG DYNAMICS...THAT WILL PROBABLY BE A CONSERVATIVE NUMBER
FOR THE MAX POTENTIAL SNOW ACCUMULATIONS. FOR QPF FROM THE MODELS...
THE STRONGER TREND HAS RESULTED IN AN UPTICK IN PCPN AMOUNTS WITH
THE 00Z ECMWF NOW COMING IN WITH A SOLID ONE-HALF TO TWO-THIRDS OF
AN INCH OF PCPN ACROSS THE FCST AREA. THE GFS HAS A LARGER SPREAD
FROM ABOUT 0.2 OVER THE KEWEENAW TO AROUND 0.75 INCHES NEAR LAKE MI.
THE GEM HAS CONSIDERABLY LESS PCPN ACROSS UPPER MI AS IT PASSES THE
MAIN SHORTWAVE/PCPN AREA SE OF UPPER MI. PTYPE WILL BE AN ISSUE AS
THERMAL PROFILES FROM CURRENT AND PREVIOUS MODEL RUNS SUGGEST THERE
WILL PROBABLY BE RAIN OR RAIN/SNOW MIX FOR A TIME AT MOST
LOCATIONS...AT LEAST AT THE ONSET OF PCPN. STRONG DYNAMIC
FORCING/HEIGHT FALLS SHOULD MAKE THE PERIOD OF LIQUID PCPN SHORT-
LIVED...ESPECIALLY AT HIGHER ELEVATIONS. SO...WE`RE PROBABLY STILL
LOOKING AT MOSTLY SNOW FOR THIS SYSTEM...OCCURRING OVERNIGHT TUE
NIGHT INTO WED MORNING. AT THIS POINT...IT APPEARS TO BE A SOLID
ADVY EVENT...THOUGH HVY/WET SNOW (LOWER SNOW TO WATER RATIOS) COULD
MAKE THIS A WARNING EVENT FOR SOME PARTS OF THE FCST AREA IF CURRENT
FCST THINKING PANS OUT.
SNOW WILL DIMINISH FROM W TO E WED...AND SOME -SN MAY CONTINUE TO
LINGER INTO WED NIGHT WITH MID/UPPER TROF OVERHEAD. INFLUX OF COLDER
ON THU LOOKS SUFFICIENT FOR THE POTENTIAL OF LIGHT LES THAT MAY
LINGER INTO FRI.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY NIGHT)
ISSUED AT 452 AM EDT SAT MAR 21 2015
ADDITIONAL SNOW SHOWERS WILL BE POSSIBLE TODAY AT ALL 3 TAF
SITES...WITH THE BEST CHANCE BEING AT CMX. CMX WILL BE CLOSER TO THE
COLDER AIR AND HAVE MORE FAVORABLE WINDS OUT OF A W TO N DIRECTION.
STEADY WINDS AND SIGNIFICANT/DOMINANT BANDED LAKE EFFECT SNOW
SHOWERS ARE NOT EXPECTED...JUST A FEW NUISANCE SNOW SHOWERS. GUSTS
NEAR 20KTS /ONCE AGAIN STRONGEST AT CMX/ WILL DIMINISH DURING THE
AFTERNOON HOURS AS LIGHTER WINDS/HIGH PRESSURE NEAR FROM THE
NORTHWEST. VFR CEILINGS/VIS ARE EXPECTED FOR MOST OF THIS PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT SAT MAR 21 2015
LOW PRESSURE OVER FAR S ONTARIO WILL CONTINUE TO EXIT E
TODAY...MAKING WAY FOR THE LARGE HIGH OVER MUCH OF CENTRAL CANADA TO
SLOWLY BUILD ACROSS THE UPPER GREAT LAKES. LOOK FOR THE WEAK RIDGE
ACROSS LAKE SUPERIOR TO BUILD SUNDAY INTO MONDAY. N-NNW GUSTS
NEARING 25-30KTS WILL BE POSSIBLE TODAY. THE HIGH WILL THEN SLIDE
ACROSS THE LOWER GREAT LAKES MONDAY NIGHT INTO TUESDAY. A LOW
PRESSURE OVER THE DAKOTAS ON TUESDAY WILL CROSS THE UPPER GREAT
LAKES LATE TUESDAY NIGHT INTO WEDNESDAY...AND EXIT INTO SE CANADA
WEDNESDAY NIGHT. ANOTHER ROUND OF GUSTS NEAR 25KTS WILL AGAIN BE
POSSIBLE LATE TUESDAY NIGHT THROUGH THRUSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...KF
LONG TERM...ROLFSON
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
700 AM EDT SAT MAR 21 2015
.AVIATION...
THE AREA OF RAIN OVER MID MI HAS REORGANIZED FURTHER NORTH WHICH IS
LEADING TO A DRIER FORECAST FOR MBS AND FNT. A COLD FRONT WILL DROP
THROUGH THE AREA THIS MORNING BRINGING BEHIND IT GUSTY NORTHERLY
FLOW...GUSTING TO AROUND 20 KNOTS...AND DRIER AIR. THIS DRY AIR WILL
ERODE THE CURRENT IFR CLOUD FIELD SET UP ACROSS SE MI SOUTH OF
THE FRONT IN THE MOISTURE RICH SW FLOW. THE DIMINISHING TREND
WILL LAST THROUGH THE EVENING AND OVERNIGHT. SOME MVFR VSBY
RESTRICTIONS ARE PRESENT BUT WILL DISSIPATE THROUGH THE MORNING
HOURS.
FOR DTW...MVFR VSBYS ARE MOVING NORTH INTO THE STATE AS MOISTURE
POOLS UP AHEAD OF AN APPROACHING COLD FRONT. IN ADDITION...IFR CIGS
ARE FILLING IN ACROSS SOUTHERN MI HEADING TOWARD THE METRO AREA
AND MAY AFFECT THE TERMINAL UNTIL THE COLD FRONT MOVES THROUGH
THIS MORNING. DRIER AIR BEHIND THE FRONT WILL RESULT IN A CLEARING
TREND THIS AFTERNOON AND EVENING.
//DTW THRESHOLD PROBABILITIES...
* MODERATE FOR CEILING BELOW 5000 FT THROUGH EARLY THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 301 AM EDT SAT MAR 21 2015
SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....DRK
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1034 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FIRST VISUALS SHOW A WIDESPREAD LOW OVERCAST AND OBSERVATIONS
SHOW A LOT OF FOG IN THE 1-4 MILE RANGE. CLOUDS WILL BE MORE
COMMON THAN SUN TODAY AHEAD OF THE COLD FRONT THAT WILL ULTIMATELY
SHIFT OUR WINDS TO THE NW AND EVENTUALLY BRING SOME DRIER AIR AND
IMPROVEMENT.
I USED THE HRRR TO BUMP UP POPS INTO THE CENTRAL MOUNTAINS AS THE
GUIDANCE SUGGESTS SHOWERS WILL REMAIN FAIRLY ORGANIZED AS THEY
DROP OUT OF THE NRN MOUNTAINS...BEFORE BECOMING MORE SCATTERED
OVER THE SRN TIER COUNTIES.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACROSS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS REACHING
AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
LATEST TIMING SHOWS THE COLD MOVING THROUGH MY SOUTHERN ZONES BY
AROUND 00Z/8PM...AND PUSH SOUTH OF THE BORDER BY MIDNIGHT. SHOWERS
WILL DIMINISH RAPIDLY IN THE POST FRONTAL DRIER AIRMASS. OTHER
THAN SOME SCATTERED FLURRIES...IT WILL BE DRY OVER MOST OF THE
REGION BY LATE EVENING.
OVERNIGHT LOWS IN THE MID TEENS TO MID 20S WILL BE SOME 5 TO 10
DEG BELOW NORMAL FOR THE FIRST DAY OF SPRING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS WILL GRADUALLY IMPROVE TODAY
AS A COLD FRONT SWEEPS SOUTHEAST ACROSS THE AIRSPACE FROM THE
GREAT LAKES. A BAND OF MAINLY LIGHT SHOWERS WILL ACCOMPANY THE
COLD FRONT THROUGH THE AIRSPACE LATER TODAY...WITH A RETURN TO VFR
PROJECTED FOR MOST SITES TONIGHT.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
757 AM EDT SAT MAR 21 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BE OVER CENTRAL PA EARLY TODAY.
A STRONG COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS
AFTERNOON AND THIS EVENING. THIS FRONT WILL REINFORCE THE COLD
AIR AND RESULT IN BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ABUNDANT LOW LVL MOISTURE...LIGHT WIND AND A VERY NARROW
TEMP/DEWPT SPREAD OVER THE FRESH SNOW COVER WAS PROMOTING PLENTY
OF STRATUS AND AREAS OF 2-3SM FOG ACROSS CENTRAL AND ERN PENN.
THE FOG WILL CONTINUE TO BE LOCALLY DENSE THROUGH 13Z ACROSS THE
LAUREL HIGHLANDS AND ADJACENT AREAS NEAR THE I-99 CORRIDOR.
LATEST HRRR AND RAP TIME-SECTIONS OF RH SHOW THE LOW STRATUS DECK
HOLDING TOUGH THROUGH 13-14Z BEFORE LIFTING BY UP TO 1000 FT
DURING THE LATE MORNING AND AFTERNOON HOURS.
EXPECT NOTHING MORE THAN SOME VERY PATCHY/LIGHT DRIZZLE THROUGH
13Z.
TEMPS EARLY TODAY WILL STAY STEADY BETWEEN 29-32F...OR FALL JUST
A DEG OR 2 IN SOME LOCATIONS /MAINLY THE NRN TIER/ WHERE SOME
PARTIAL CLEARING OCCURS.
ICY SPOTS ARE POSSIBLE ON UNTREATED ROADS.
WEAK RIDGE OF HIGH PRESSURE WILL SLIDE EAST OF THE REGION BY THE
LATE MORNING HOURS...ALLOWING AN 8-12 KT WSWRLY FLOW TO DEVELOP
BETWEEN IT...AND A STRONG COLD FRONT APPROACHING FROM THE GLAKES
REGION.
THE PERSISTENT AND MDTLY STG SUBSIDENCE INVERSION BASED BETWEEN
3-4 KFT AGL SHOULD HELP TO MAINTAIN PLENTY OF TRAPPED STRATUS AND
STRATO CU THIS MORNING. AFTERWARD...THE AFOREMENTIONED COLD FRONT
WILL SPARK SOME RAIN/SNOW SHOWERS ACROSS THE NW MTNS LATE THIS
MORNING AND THIS AFTERNOON. MUCH MORE ISOLATED-SCTD RAIN SHOWERS
WILL FALL ACROSS THE CENTRAL AND SOUTHERN PENN LATE THIS
AFTERNOON AND EARLY THIS EVENING.
CONSENSUS ALL BLEND OF MODEL TEMPS YIELDS AFTERNOON HIGHS AROUND
40F ACRS THE NW MTNS...AND MID-UPPER 40S ACROSS MUCH OF CENTRAL
AND SRN PENN. THE LOWER SUSQ VALLEY WILL LIKELY SEE TEMPS
REACHING AROUND 50F FOR AFTERNOON HIGHS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE COLD FRONT SHOULD NEARLY BISECT THE STATE FROM NE-SW AT
00Z...AND PUSH ACROSS THE LOWER SUSQ VALLEY THIS EVENING.
GEFS AND 00Z-06 OPER MDL GUIDANCE SUPPORT LIKELY RAIN SHOWERS
ACROSS THE NW MTNS ACCOMPANYING THE FROPA. EVEN THE LOWER SUSQ
VALLEY COULD SEE A SHOWER IN SPOTS WITH THE EARLY EVENING FROPA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SUN NIGHT
INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT
WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW
AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS
THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE
SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF
CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID
50S.
SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A
WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS
A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD
SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT
MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED
FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW
TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME
WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER
THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO
BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE.
BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER
PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW
SHOWERS FOR LATER FRI INTO THE WEEKEND.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
WIDESPREAD LOW CIGS AND REDUCED VSBYS WILL GRADUALLY IMPROVE TODAY
AS A COLD FRONT SWEEPS SOUTHEAST ACROSS THE AIRSPACE FROM THE
GREAT LAKES. RADAR SHOWS AN AREA OF -SN ALONG WARM FRONT THAT
WILL BRIEFLY AFFECT IPT THRU 13Z. A BAND OF -RA MAY ALSO ACCOMPANY
THE COLD FRONT THROUGH THE AIRSPACE LATER TODAY...WITH A RETURN
TO VFR PROJECTED FOR MOST SITES TONIGHT.
OUTLOOK...
SUN-TUE...VFR/NO SIG WX.
WED...VFR/MVFR WITH CHC OF -RA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS NEW YORK NY
635 PM EDT SAT MAR 21 2015
.SYNOPSIS...
A COLD FRONT CROSSES THE TRI-STATE INTO THE EARLY MORNING
HOURS...THEN CANADIAN HIGH PRESSURE THEN BUILDS IN THROUGH
TUESDAY. THE HIGH MOVES OFF SHORE WEDNESDAY AS LOW PRESSURE
APPROACHES FROM THE WEST. A COLD FRONT ASSOCIATED WITH THE LOW
CROSSES THE REGION THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE
BUILDS IN FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
RADAR INDICATING SOME LIGHT RAIN SHOWERS OR SPRINKLES POSSIBLE
COMING INTO THE LOWER HUDSON VALLEY WITH RETURNS OF 16 TO 20 DBS.
ALSO HRRR PICKING UP ON SOME SPRINKLES THROUGH 02Z. SO ADDED
SPRINKLES ACROSS ORANGE...PUTNAM...ROCKLAND...AND WESTCHESTER
COUNTIES.
ALSO...TEMPERATURES HAVE BEEN SLOW TO DROP AND ADJUSTED UPWARD
THROUGH THIS EVENING.
WITH 700-500 HPA TROUGH AXIS ALREADY TO THE N/E THE BEST FORCING
SHOULD STAY TO OUR N/E TONIGHT...ALLOWING FOR SURFACE COLD FRONTAL
PASSAGE THIS EVENING/THE EARLY MORNING HOURS TO BE DRY.
FOR LOWS TONIGHT...USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES. LOWS SHOULD BE AROUND 5 DEGREES BELOW
NORMAL. TEMPERATURES WILL NOT FALL OFF THAT MUCH THIS EVENING
AHEAD OF THE COLD FRONT...BUT SHOULD FALL OFF FAIRLY RAPIDLY AS
MODERATE TO STRONG LOW LEVEL COLD ADVECTION ON SETS BEHIND THE
FRONT DUE TO INCREASING NW WINDS.
NW WINDS SHOULD GUST TO AROUND 20-30 MPH BY AROUND SUNRISE...WITH
WIND CHILLS GENERALLY FROM THE MID TEENS TO AROUND 20.
GIVEN DELAY IN FALL OFF OF TEMPERATURES...AND SOME UNCERTAINTY IF
NYC AND PARTS OF LONG ISLAND WILL REACH FREEZING...WILL HOLD OFF
ON ISSUING AN SPS FOR BLACK ICE FOR NOW.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT AS A PROTUBERANCE OF THE
POLAR VORTEX PASSES TO OUR N THEN NE ACROSS SE CANADA/FAR N NEW
ENGLAND. GIVEN ASSOCIATED LOW LEVEL COLD POOL...WILL BE A FIGHT
BETWEEN DOWN SLOPING LOW LEVEL FLOW AND LOW LEVEL INSTABILITY FOR
EXTENT OF CLOUD COVER BY SUNDAY AFTERNOON. FOR NOW GOING MAINLY
MOSTLY SUNNY ON SUNDAY.
FOR HIGHS SUNDAY A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 875 TO 850 HPA PER BUFKIT
SOUNDINGS WAS USED. HIGHS SHOULD BE AROUND 15 DEGREES BELOW NORMAL
- WITH MOST AREAS STRUGGLING TO REACH THE LOWER TO MID 30S AND
HIGHER ELEVATIONS STRUGGLING TO REACH THE 30 DEGREE MARK.
NW WINDS GUSTING TO AROUND 30 MPH...WITH SOME OCCASIONAL GUSTS TO
35 OR MAYBE EVEN 40 MPH WILL KEEP WIND CHILLS MAINLY FROM THE
UPPER TEENS TO MID 20S.
FOR LOWS SUNDAY NIGHT A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES WAS USED...WITH VALUES FORECAST TO BE AROUND 15
DEGREES BELOW NORMAL. WINDS DIMINISH THROUGH THE NIGHT...BUT STILL
SHOULD PRODUCE WIND CHILLS MAINLY IN THE SINGLE DIGITS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
SURFACE CANADIAN HIGH PRESSURE WILL BE BUILDING INTO THE AREA MONDAY
INTO TUESDAY NIGHT WHILE ALOFT A WEAK UPPER TROUGH REMAINS ACROSS
THE NORTHEAST AND INTO EASTERN CANADA. A WEAK SHORTWAVE ROTATES
THROUGH TUESDAY...HOWEVER THERE IS LITTLE MID AND LOWER LEVEL
SUPPPORT...WITH SUBSIDENCE ASSOCIATED WITH THE HIGH...AND LITTLE
MOISTURE. THE SHORTWAVE MOVE THROUGH WITH JUST SOME HIGH CLOUDINESS.
WITH THE RIDGE MOVING OFFSHORE WEDNESDAY WARM ADVECTION SETS UP LATE
TUESDAY NIGHT INTO WEDNESDAY WITH A DEVELOPING WARM FRONTAL BOUNDARY
TO THE WEST AND SOUTH...THROUGH CENTRAL PENNSYLVANIA TO SOUTHERN NEW
JERSEY. LIGHT SHOWERS WILL BE POSSIBLE BY WEDNESDAY AFTERNOON WITH
INCREASING ISENTROPIC LIFT WITH THE FRONT. IN ADDITION THE WARM
ADVECTION WILL QUICKLY REPLACE ANY COLD AIR AND ALL LIQUID
PRECIPITATION IS EXPECTED.
MINOR DIFFERENCES WITH THE TIMING OF THE COLD FRONT LATE THURSDAY
INTO THURSDAY NIGHT. HAVE BROUGHT THE FRONT THROUGH SLOWLY...THURSDAY
NIGHT...MORE TOWARD THE ECMWF...AS THE FLOW BECOMES MORE
PARALLEL TO THE FRONT.
BROAD UPPER TROUGH REMAINS INTO NEXT WEEKEND AS SURFACE HIGH SLOWLY
BUILDS. COULD BE SOME POST FRONTAL RAIN SHOWERS...RAIN AND SNOW
SHOWERS INLAND...AND WILL KEEP SLIGHT CHANCE POPS FRIDAY INTO
SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE REMAINS IN PLACE THIS AFTERNOON. A COLD FRONT PASSES
THROUGH TONIGHT.
VFR. COULD BE TEMPO MVFR THIS AFTN WITH CIGS 2000-3000 FEET. NOT
ENOUGH CONFIDENCE TO INCLUDE IN TAFS.
SW-WSW WINDS AROUND 10 KT THIS AFTERNOON. WINDS VEER TO THE
WEST/NORTHWEST JUST BEFORE MIDNIGHT. GUSTS OVERNIGHT MIGHT BE ONLY
OCCASIONAL FOR SOME LOCATIONS. SUSTAINED WINDS AND GUSTS INCREASE
DURING SUNDAY MORNING.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
.SUN PM...VFR. NW GUSTS 20-25 KT.
.MON...VFR. NW GUSTS AROUND 20 KT.
.TUE...VFR.
.WED...CHANCE OF SUB-VFR/SHRA IN AFTN.
.THU...CHC OF SUB-VFR/SHRA. SW GUSTS 20-25 KT.
&&
.MARINE...
SE SWELLS PERSIST ON THE COASTAL OCEAN WATERS...KEEPING THE SEAS
UP. WINDS INCREASE BEHIND A COLD FRONT TONIGHT...BRINGING GUSTS TO
SCA LEVELS ON ALL WATERS AFTER MIDNIGHT TONIGHT...WITH SCA GUSTS
CONTINUING ON ALL WATERS THROUGH SUNDAY AFTERNOON. SCA LEVEL GUSTS
ARE EXPECTED TO CONTINUE ON THE COASTAL OCEAN WATERS...EASTERN
SOUND AND THE BAYS OF LONG ISLAND SUNDAY NIGHT. AS A RESULT HAVE
EXTENDED THE SCA ON ALL WATERS THROUGH SUNDAY AFTERNOON AND ON THE
COASTAL OCEAN WATERS...EASTERN SOUND AND THE BAYS OF LONG ISLAND
THROUGH SUNDAY NIGHT.
HIGH PRESSURE WILL BE BUILDING INTO THE WATERS MONDAY AND
MOVE EAST OF THE WATERS WEDNESDAY. WIND AND SEAS WILL REMAIN BELOW
SMALL CRAFT LEVELS MONDAY THROUGH WEDNESDAY.
AS THE HIGH MOVES OFF SHORE WEDNESDAY AND A LOW APPROACHES FROM THE
WEST AN INCREASING SOUTHERLY FLOW WILL DEVELOP. ON THE OCEAN SMALL
CRAFT GUSTS WILL BE POSSIBLE BY THURSDAY...AND SEAS BUILD TO 5 FT OR
HIGHER BY THURSDAY. SMALL CRAFT CONDITIONS REMAIN INTO THURSDAY
NIGHT. A COLD FRONT CROSSES THE WATERS THURSDAY NIGHT AND HIGH
PRESSURE BUILD IN FROM THE WEST. WIND AND SEAS SUBSIDE TO BELOW
SMALL CRAFT THURSDAY NIGHT AND REMAIN BELOW FRIDAY.
&&
.HYDROLOGY...
DRY THROUGH TUESDAY NIGHT. AROUND A HALF INCH OF PRECIPITATION IS
EXPECTED FROM WEDNESDAY AFTERNOON THROUGH THURSDAY NIGHT.
ICE BREAKUP/MOVEMENT ACROSS THE LOWER HUDSON VALLEY AND
CONNECTICUT RIVERS/STREAMS IS EXPECTED TO BE LIMITED THROUGH
EARLY NEXT WEEK WITH LITTLE RUNOFF AND BELOW SEASONABLE TEMPS.
ISOLATED ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD
RESULT IN LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS
UNPREDICTABLE AND SUDDEN...INTERESTS ALONG ICE COVERED RIVERS
SHOULD MONITOR NWS FORECASTS FOR THE LATEST INFORMATION.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT SUNDAY
FOR ANZ335-338.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EDT MONDAY
FOR ANZ330-340-345.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT/MET
NEAR TERM...MALOIT/MET
SHORT TERM...MALOIT
LONG TERM...MET
AVIATION...JC
MARINE...MALOIT/MET
HYDROLOGY...MALOIT/MET
AREA FORECAST DISCUSSION...RESENT
NWS JACKSON KY
320 PM EDT SAT MAR 21 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 320 PM EDT SAT MAR 21 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST
KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH
CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF
THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE...
DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH
AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES
ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF
CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID
50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST...
THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE
HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY
BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY
MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING
THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY
BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS
OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT
INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON
SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE
HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY
MORNING.
SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH
CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE
CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP
INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE.
EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND
RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER
THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE
MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING
OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF
THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES
ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY
DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS
TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF
FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST
FOR NOW...BUT DID ADD SOME TO THE GRIDS.
AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO
SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR
POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD.
AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 235 PM EDT SAT MAR 21 2015
THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW
EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE
PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN
UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A
SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND.
THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING
THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF
THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR
NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT
TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE
SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF
THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A
SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN
ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO
THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY
WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF
RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A
SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH
WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH.
A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL
COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO
AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY
NIGHT. THE OPERATIONAL GFS IS THE MOST AGRESSIVE MODEL WITH THE COLD
AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL
COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO
WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY
REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 155 PM EDT SAT MAR 21 2015
NOW THAT THE LOW CLOUDS HAVE BROKEN UP VFR CONDITIONS WILL
DOMINATE THE FORECAST WITH THE ONLY CIGS EXPECTED TO BE ABOVE 20K
FEET THROUGH THE NIGHT. HAVE INCLUDED A TOUCH OF VALLEY FOG IN
THE GRIDS LATE TONIGHT AND ALSO ALLOWED SOME MVFR BR TO SLIP INTO
THE SME TAF SITE TOWARDS DAWN...OTHERWISE NO RESTRICTIONS. BREEZY
CONDITIONS ARE FOUND AT SYM THIS AFTERNOON WITH LIGHTER WINDS
ELSEWHERE...GENERALLY FROM THE SOUTHWEST. LOOK FOR ALL WINDS TO
DIE DOWN THIS EVENING WITH ONLY LIGHT AND VARIABLE ONES EXPECTED
THROUGH THE DAY SUNDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SBH
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1027 AM EDT SAT MAR 21 2015
OVERALL...JUST MINOR TWEAKS TO THE GOING FORECAST...LARGELY TO THE
LAKE EFFECT POPS/CLOUDS TO MATCH UP WITH THE ONGOING SNOW SHOWERS.
WITH RAP ANALYZED 850MB TEMPS AROUND -16C OVER LAKE
SUPERIOR...THERE IS PLENTY OF OVER THE LAKE INSTABILITY TO LEAD TO
LAKE EFFECT. BUT THE COMBINATION OF THE REMAINING ICE AND LIMITED
MOISTURE HAS IMPACTED THE COVERAGE SO FAR THIS MORNING UNDER
GENERALLY NORTHERLY WINDS. THUS...AREAS OVER THE KEWEENAW PENINSULA
AND TOWARDS LUCE COUNTY HAVE BEEN MOSTLY SUNNY DUE TO THE UPSTREAM
ICE COVER. HAVE TRIMMED BACK POPS/CLOUDS FOR THOSE AREAS THROUGH
THE MORNING AND EARLY AFTERNOON UNTIL 950-925MB WINDS BEGIN TO BACK
TOWARDS 290-300 DEGREES AROUND 18Z. THEN TRENDED POPS UP DOWNSTREAM
OF THE ICE FREE AREAS OF LAKE SUPERIOR WITH THAT WIND DIRECTION.
OTHERWISE...TRENDED POPS UP TO HIGH CHANCE VALUES FOR THE NORTH
CENTRAL THIS MORNING WITH THE OPEN WATER SOUTHEAST OF THE KEWEENAW
PENINSULA AND FAVORED WIND DIRECTION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT SAT MAR 21 2015
SPRING IN UPPER MI USUALLY MEANS MORE SNOW...SO HERE WE GO. THE CWA
IS CURRENTLY IN BETWEEN WEATHER MAKERS. THE INITIAL LOW AND
ASSOCIATED COLD FRONT THAT BROUGH A MIXED BAG OF PRECIP ARE EXITING
FAR E UPPER MI/LAKE HURON. THE SECOND WEATHER MAKER IS IN THE FORM
OF COOLER AIR THAT WILL BE PUSHING IN ON FAVORABLE N-NW WINDS LATER
THIS MORNING. HOWEVER...A CLEARING SKY HAS BEEN THE RESULT OVER MUCH
OF THE W HALF OF UPPER MI AS DRY AIR LOOKS TO BE STEADY FORCE
UPSTREAM. THIS HAS BEEN MORE TEMPORARY OVER THE KEWEENAW AS LAKE
EFFECT CLOUDS DEVELOP IN THE OPEN WATERS TO THE N. ICE
COVER...ALTHOUGH THIN...LOOKS EXPANSIVE N OF SLEEPING AND MISERY
BAYS /NE OF ONTONAGON/. THIS WILL INHIBIT SOME OF THE LES THAT IS
EXPECTED TO DEVELOP LATER TODAY AS 850MB TEMPS FALL FROM AN AVERAGE -
10C EARLY THIS MORNING TO -13C BY THE END OF THE DAY...AND -16C BY
06Z SUNDAY. NOT EXPECTING MUCH SNOW...WHICH WILL BE ALONG THE
TRADITIONAL N-NW LES AREAS. WITH THE COOLER AIR SWEEPING IN..EXPECT
HIGHS ONLY IN THE 20S OR 30S. NORMAL HIGHS THIS TIME OF YEAR ARE IN
THE MID TO UPPER 30S. THE SFC HIGH OVER MUCH OF CENTRAL CANADA WILL
CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES...WITH THE N FLOW
CONTINUING...BUT LIGHTER. THIS WILL KEEP WINDS AROUND 5KTS THROUGH
THE OVERNIGHT HOURS. LOWERED THE FCST SLIGHTLY FOR TONIGHT...WITH
THE COLDEST AIR SLOWLY EXITING TO THE E...AND LIGHT WINDS AS THE SFC
HIGH SHIFTS MORE OVERHEAD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 536 AM EDT SAT MAR 21 2015
THRU LATE MONTH AND INTO EARLY APR...IT APPEARS PATTERN WILL
CONTINUE TO FAVOR RIDGING OVER WRN NAMERICA AND TROFFING OVER ERN
NAMERICA. AS A RESULT...WHILE THERE WILL BE OCCASIONAL DAYS OF ABOVE
NORMAL TEMPS FOR UPPER MI...THE PATTERN ON THE WHOLE WILL SUPPORT
NORMAL TO BELOW NORMAL TEMPS WITH BLO NORMAL LIKELY THE MORE COMMON
OUTCOME FOR THE MAJORITY OF DAYS. THE MJO IS CURRENTLY VERY
STRONG...AND WHILE IT IS FCST TO WEAKEN...THE PHASE OF THE MJO WILL
FAVOR BLO NORMAL TEMPS FOR THE GREAT LAKES LATE THIS MONTH INTO
EARLY APR...FURTHER SUPPORTING THE COOL INDICATIONS FROM OTHER
GUIDANCE. WITH NW FLOW MOSTLY PREVAILING...PCPN OVERALL WILL ALSO
LIKELY BE BLO NORMAL FOR AT LEAST THE NEXT 2-3 WEEKS...CONTINUING
THE DRY SYNOPTIC TREND NOTED FOR THE YEAR SO FAR (NEARLY ALL OF
UPPER MI IS RUNNING BLO NORMAL PCPN FOR THE YEAR...AND MUCH OF WI
INTO PORTIONS OF SCNTRL AND WRN UPPER MI ARE JUST 25-50PCT OF NORMAL
PCPN). WHILE BLO NORMAL PCPN WILL BE FAVORED OVERALL...THERE WILL BE
ONE SYSTEM AT THE MIDDLE OF NEXT WEEK THAT SHOULD PROVIDE WIDESPREAD
MDT PCPN...A RARE EVENT FOR UPPER MI SO FAR THIS YEAR. MORE ON THAT
LATER.
BEGINNING SUN...WITH 850MB TEMPS AS LOW AS -20C OVER ERN LAKE
SUPERIOR...EXPECT NW FLOW LES INTO AREAS EAST OF MARQUETTE. THE
LARGER OPEN WATER AREA TO THE LEE OF THE KEWEENAW WILL BE A PLUS FOR
LES INTO ALGER COUNTY. ALTHOUGH FCST SOUNDINGS SHOW INVERSIONS AT
AROUND 4KFT...THE DGZ OCCUPIES MUCH OF THE CONVECTIVE LAYER...AND
THAT MAY HELP FLUFF UP AN INCH OR 2 OF SNOW ACCUMULATION IF SHSN ARE
PERSISTENT AT ANY ONE LOCATION SUN MORNING. WITH MUCH MORE
PRONOUNCED ANTICYCLONIC FLOW INTO WRN LAKE SUPERIOR ASSOCIATED WITH
SFC HIGH PRES RIDGE NOSING INTO THE UPPER LAKES AND WITH 850MB TEMPS
ONLY AROUND -13C AT 12Z SUN...THERE MAY NOT BE MUCH MORE THAN
FLURRIES OFF WRN LAKE SUPERIOR DESPITE CONSIDERABLY MORE OPEN WATER
THAN OVER ERN LAKE SUPERIOR. MODERATION OF 850MB TEMPS SUN AFTN
WORKING IN CONCERT WITH THE DISRUPTIVE EFFECT OF SPRINGTIME SOLAR
INSOLATION ON LES WILL LIKELY SPELL AN END TO LES IN THE AFTN OVER
THE E OR AT LEAST A DIMINISHING TO FLURRIES. EXPECT HIGHS IN THE 20S
AND 30S...WARMEST TOWARD THE MI/WI BORDER.
SUN NIGHT/MON LOOK QUIET WITH SFC HIGH PRES IN CONTROL. AS WAS THE
CASE YESTERDAY...MODELS SHOWS A SHORTWAVE MOVING FROM THE DAKOTAS
INTO THE WRN GREAT LAKES WITH ASSOCIATED PCPN SPREADING ACROSS MN/WI
SUN NIGHT. GEM AND ECMWF BRING PCPN VERY NEAR THE WI/MI BORDER.
GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES AND DRY AIR EMANATING
FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF
HERE...A DRY FCST IS THE WAY TO GO. SUN NIGHT SHOULD BE QUITE
CHILLY...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH CLOUDS WILL BE
THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT
TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO.
MON NIGHT/TUE...ANOTHER WEAKENING SHORTWAVE WILL TRACK ESE INTO THE
WRN LAKES MON NIGHT. AT THE SAME TIME...UPPER RIDGE WILL BE MOVING
INTO THE UPPER MISSISSIPPI VALLEY/WRN GREAT LAKES DOWNSTREAM OF
FALLING HEIGHTS/STRONGER WAVE SHIFTING ACROSS THE NRN ROCKIES INTO
THE NRN PLAINS. THIS WILL SUPPORT LARGE SFC HIGH PRES OVER THE GREAT
LAKES REGION MON NIGHT THAT WILL DRIFT TOWARD NEW ENGLAND TUE. AS A
RESULT...ANY PCPN ASSOCIATED WITH WEAKENING SHORTWAVE SHOULD
DISSIPATE WITH TIME BEFORE REACHING UPPER MI.
NOW ONTO THE MAIN FEATURE FOR THIS FCST PERIOD. COMPLEX OF SHORTWAVE
ENERGY MOVING ONSHORE OVER THE PACIFIC NW SUN NIGHT/MON MORNING
WILL REACH THE WRN PLAINS TUE AND THEN MOVE ACROSS THE WRN GREAT
LAKES WED. 00Z MODEL GUIDANCE HAS OVERALL TRENDED MORE ROBUST WITH
THE MAIN SHORTWAVE ENERGY REACHING NEBRASKA TUE AND THEN WI/MI WED
MORNING. COMPLICATING FACTOR IS ADDITIONAL SHORTWAVE ENERGY MOVING
MORE SLOWLY ACROSS THE DAKOTAS AND HOW IT AFFECTS/INTERACTS WITH THE
MAIN WAVE. THIS WILL NO DOUBT CAUSE FLUCTUATIONS IN THE UPCOMING
MODEL RUNS...AND IT PROBABLY WON`T BE CLARIFIED UNTIL WE GET INTO
THE SHORT RANGE WITH THIS SYSTEM. THAT SAID...AS MENTIONED...MODELS
FOR NOW HAVE OVERALL TRENDED STRONGER WITH THE MAIN WAVE WHICH TAKES
ON A BRIEF NEGATIVE TILT AT AN OPTIMUM TIME AS IT SWINGS INTO THE
WRN GREAT LAKES. LOOKS LIKE QUITE THE DYNAMIC SYSTEM WITH 00Z
GFS/ECMWF SHOWING CENTER OF IMPRESSIVE 12HR 500MB HEIGHT FALLS OF
170-200M TRACKING ACROSS WI INTO ERN UPPER MI/STRAITS AREA. ALSO
NOTED IS STRONG DIFFLUENCE IN LEFT EXIT OF 100+KT UPPER JET AIMING
INTO LWR MI. ISENTROPIC ANALYSIS SHOWS MIXING RATIOS OF 3 TO 3.5G/KG
AVBL AROUND 750MB. WITH WHAT LOOKS LIKE ABOUT 9HRS OF GOOD ASCENT...
THIS WOULD SUGGEST THE POTENTIAL FOR ROUGHLY 5 INCHES OF SNOW. GIVEN
THE STRONG DYNAMICS...THAT WILL PROBABLY BE A CONSERVATIVE NUMBER
FOR THE MAX POTENTIAL SNOW ACCUMULATIONS. FOR QPF FROM THE MODELS...
THE STRONGER TREND HAS RESULTED IN AN UPTICK IN PCPN AMOUNTS WITH
THE 00Z ECMWF NOW COMING IN WITH A SOLID ONE-HALF TO TWO-THIRDS OF
AN INCH OF PCPN ACROSS THE FCST AREA. THE GFS HAS A LARGER SPREAD
FROM ABOUT 0.2 OVER THE KEWEENAW TO AROUND 0.75 INCHES NEAR LAKE MI.
THE GEM HAS CONSIDERABLY LESS PCPN ACROSS UPPER MI AS IT PASSES THE
MAIN SHORTWAVE/PCPN AREA SE OF UPPER MI. PTYPE WILL BE AN ISSUE AS
THERMAL PROFILES FROM CURRENT AND PREVIOUS MODEL RUNS SUGGEST THERE
WILL PROBABLY BE RAIN OR RAIN/SNOW MIX FOR A TIME AT MOST
LOCATIONS...AT LEAST AT THE ONSET OF PCPN. STRONG DYNAMIC
FORCING/HEIGHT FALLS SHOULD MAKE THE PERIOD OF LIQUID PCPN SHORT-
LIVED...ESPECIALLY AT HIGHER ELEVATIONS. SO...WE`RE PROBABLY STILL
LOOKING AT MOSTLY SNOW FOR THIS SYSTEM...OCCURRING OVERNIGHT TUE
NIGHT INTO WED MORNING. AT THIS POINT...IT APPEARS TO BE A SOLID
ADVY EVENT...THOUGH HVY/WET SNOW (LOWER SNOW TO WATER RATIOS) COULD
MAKE THIS A WARNING EVENT FOR SOME PARTS OF THE FCST AREA IF CURRENT
FCST THINKING PANS OUT.
SNOW WILL DIMINISH FROM W TO E WED...AND SOME -SN MAY CONTINUE TO
LINGER INTO WED NIGHT WITH MID/UPPER TROF OVERHEAD. INFLUX OF COLDER
ON THU LOOKS SUFFICIENT FOR THE POTENTIAL OF LIGHT LES THAT MAY
LINGER INTO FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 142 PM EDT SAT MAR 21 2015
COLD AIR ALOFT MOVING OVER THE ICE FREE AREAS OF LAKE SUPERIOR HAS
LED TO LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF UPPER MICHIGAN
THIS AFTERNOON ALONG WITH OCCASIONAL MVFR CEILINGS. EXPECT ANY
MVFR CEILINGS AT THE START OF THE PERIOD TO RISE TO VFR WITHIN A
COUPLE HOURS AS DRIER AIR MOVES INTO THE AREA. THESE VFR CONDITIONS
WILL PREVAIL AT THE TAF SITES INTO THE EVENING HOURS BEFORE ANOTHER
WEAK SURGE OF MOISTURE INCREASES THE LAKE EFFECT CLOUD COVERAGE
LATE THIS EVENING AND INTO THE OVERNIGHT HOURS AS WINDS TURN BACK
TO THE NORTH-NORTHWEST. THINK KSAW HAS THE BEST OPPORTUNITY FOR
HIGH END MVFR CEILINGS...SO HAVE INCLUDED IT IN THE FORECAST.
CONFIDENCE IS TOO LOW AT THE OTHER TWO SITES TO INCLUDE. THIS
MOISTURE WILL DEPART SUNDAY MORNING AND WINDS WILL BACK (LEADING TO
DIMINISHING CLOUDS/SNOW)...AS THE RIDGE CONTINUES TO MOVE OVER THE
REGION.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT SAT MAR 21 2015
LOW PRESSURE OVER FAR S ONTARIO WILL CONTINUE TO EXIT E
TODAY...MAKING WAY FOR THE LARGE HIGH OVER MUCH OF CENTRAL CANADA TO
SLOWLY BUILD ACROSS THE UPPER GREAT LAKES. LOOK FOR THE WEAK RIDGE
ACROSS LAKE SUPERIOR TO BUILD SUNDAY INTO MONDAY. N-NNW GUSTS
NEARING 25-30KTS WILL BE POSSIBLE TODAY. THE HIGH WILL THEN SLIDE
ACROSS THE LOWER GREAT LAKES MONDAY NIGHT INTO TUESDAY. A LOW
PRESSURE OVER THE DAKOTAS ON TUESDAY WILL CROSS THE UPPER GREAT
LAKES LATE TUESDAY NIGHT INTO WEDNESDAY...AND EXIT INTO SE CANADA
WEDNESDAY NIGHT. ANOTHER ROUND OF GUSTS NEAR 25KTS WILL AGAIN BE
POSSIBLE LATE TUESDAY NIGHT THROUGH THRUSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...KF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...KF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1254 PM EDT SAT MAR 21 2015
.AVIATION...
AREAS OF DRIZZLE HAVE DEVELOPED IN ADVANCE OF THE PRIMARY
WINDSHIFT/COLD FRONT THAT IS SETTLING SOUTHWARD ACROSS
SOUTHEASTERN MICHIGAN. ORIENTATION OF THE BOUNDARY IN COMPARISON
TO THE MEAN FLOW BRINGS UNCERTAINTY TO THE EVENTUAL TIMING AND
SOUTHWARD PROGRESSION OF THE BOUNDARY DURING THE AFTERNOON HOURS.
WHILE LOW LEVEL MOISTURE WILL SCOUR OUT RAPIDLY ONCE THE WIND
SHIFT PUSHES THROUGH...SUSPECT THE DRIZZLE AND LOW CLOUD IN
ADVANCE OF THE BOUNDARY TO PERSIST A BIT LONGER ACROSS THE SOUTH
THAN WHAT IT APPEARS AT THE MOMENT. INTRODUCED A TEMPO GROUPING
FOR DRIZZLE FOR THE SOUTHERN TAF SITES.
FOR DTW...POTENTIAL EXISTS THIS AFTERNOON FOR A PERIOD OF IFR
CONDITIONS BOTH IN CIGS/VSBY RESTRICTIONS DUE TO POOLING OF
MOISTURE AHEAD OF A COLD FRONT BOUNDARY. INCLUDED A TEMPO GROUP
WITH SOME POSSIBLE DRIZZLE. GUSTY NORTHWEST WINDS ARE EXPECTED TO
INCREASE SUBSTANTIALLY AS DRIER AIR ADVECTS INTO FAR SOUTHEASTERN
MICHIGAN LATE THIS AFTERNOON.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILING BELOW 5000 FT UNTIL LATE AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 301 AM EDT SAT MAR 21 2015
SHORT TERM...TODAY AND TONIGHT
COOL PATTERN IS SETTING UP ONCE AGAIN AS A SUB 500 DAM 500MB LOW IS
DROPPING SOUTHWARD FROM HUDSON BAY. A JET STREAK WILL GIVE IT AN
EASTWARD NUDGE KEEPING IT OVER THE ONTARIO/QUEBEC BORDER TODAY BUT
WITH RIDGING DEVELOPING OVER THE WEST COAST...COOL NORTH FLOW WILL
PREVAIL ONCE AGAIN AS IT DID FOR MOST OF THE WINTER.
WE START THE WEEKEND OUT WITH A TROUGH OF LOW PRESSURE DIRECTLY
OVERHEAD AS IT TRACKS SOUTH AND EAST. A WEAK SFC LOW TRACKING
THROUGH THE TROUGH WILL LIFT NE INTO ONTARIO THIS MORNING AS
PRESSURE FALLS RELOCATE. THE SFC COLD FRONT WILL PASS THROUGH SE MI
FROM ABOUT 13-16Z WITH LITTLE FANFARE IN THE WAY OF PRECIP AS THERE
IS LITTLE FORCING OVER MOST OF THE AREA. THE RUC DOES SEEM TO HAVE A
DECENT HANDLE ON THE COVERAGE OF THE RAIN CURRENTLY FALLING ACROSS
THE STATE AND IT SUGGESTS THAT THE LINE OF SHOWERS COMING ON SHORE
NEAR MUSKEGON AS OF 06Z MAY CLIP THE NORTHERN COUNTIES AS IT
TRAVERSES SE MI ON ITS WAY E/NE TO ONTARIO. WILL CONTINUE THE CHANCE
POPS THROUGH THE MORNING ACROSS THE NORTH TO COVERAGE THE SCATTERED
SHOWERS.
AFTER THE COLD FRONT PASSES TO THE SOUTH...GUSTY NORTHERLY WINDS
WILL BEGIN FOR THE AFTERNOON HOURS. LOOK FOR GUSTS TO PEAK IN THE 20-
25 KNOT RANGE. THESE GUSTY WINDS WILL HELP USHER IN COLD AIR FROM
CANADA AS A LARGE AREA OF HIGH PRESSURE BEGINS BUILDING INTO THE
REGION. THE FRONTAL POSITION AND TIMING WILL PRODUCE A THERMAL
GRADIENT ACROSS THE CWA IN TERMS OF HIGH TEMPS AS SOUTHERN LOCATIONS
WILL KEEP SW FLOW AND WAA ADVECTION INTO THE EARLY AFTERNOON BEFORE
THE FRONT SHUTS IT DOWN. HIGHS COULD REACH 50 NEAR THE OHIO BORDER
WITH THE THUMB POSSIBLY FAILING TO REACH 40. BY SUNDAY MORNING...925
TEMPS WILL HAVE FALLEN TO THE NEGATIVE TEENS. THIS WILL MAKE FOR A
CHILLY NIGHT...SOME 10 TO 15 DEGREES BELOW NORMAL...WHICH IS 30F.
LONG TERM...SUNDAY THROUGH FRIDAY
MID LEVEL CONFLUENT FLOW WILL OVERSPREAD LOWER MI ON SUNDAY AS THE
POLAR LOW DEPARTS INTO THE CANADIAN MARITIMES. THIS WILL FORCE
SURFACE HIGH PRESSURE TO EXPAND FROM CENTRAL CANADA INTO THE ERN
GREAT LAKES BY MONDAY. ALTHOUGH THE CORE OF ARCTIC AIR WILL SLIDE
EAST OF THE REGION ON SUNDAY...850MB TEMPS WILL STILL HOLD STEADY IN
THE NEGATIVE TEENS OVER SE MI. POTENTIAL MIXING HEIGHTS FOR LATE
MARCH SUGGEST LEANING ON THE HIGH END OF MODEL GUIDANCE...WHICH
STILL INDICATES HIGH TEMPS ONLY IN THE 30S TO AROUND 40. THE SFC
HIGH WILL RESIDE OVER THE ERN GREAT LAKES MONDAY INTO TUESDAY...
SUSTAINING A LIGHT EASTERLY WIND COMPONENT TO SE MI. THE LINGERING
SHALLOW COLD AIRMASS COMBINED WITH THE FLOW OFF THE GREAT LAKES WILL
SUPPRESS TEMPS...KEEPING READINGS ROUGHLY 10 DEGREES BELOW SEASONAL
NORMS FOR THE START OF THE WORK WEEK. THE 00Z MODEL SUITE CONTINUE
TO SHOW A REGION OF ENHANCED ISENTROPIC ASCENT SLIDING ACROSS THE
UPPER MS VALLEY SUN INTO SUN NIGHT...WHICH WILL RESULT IN SOME
MID/HIGH CLOUDS PASSING ACROSS SRN MI. THE DRY AIR ASSOCIATED WITH
THE SFC HIGH WILL KEEP THE FORECAST AREA PRECIP FREE.
THE NEXT CHANCE FOR PRECIP IS STILL EXPECTED TUES NIGHT INTO
WEDNESDAY. AMPLIFICATION OF A FAST MOVING MID LEVEL WAVE IN THE LEE
OF THE ROCKIES TUESDAY IS SHOWN BY THE 00Z MODEL SUITE. A NARROW
RIBBON OF ENHANCED MOISTURE TRANSPORT IS EXPECTED TO FUNNEL INTO
LOWER MI IN ADVANCE OF THIS WAVE AS IT LIFTS INTO THE GREAT LAKES
REGION TUES NIGHT. THE 00Z GFS BECOMES CONSIDERABLY MORE AMPLIFIED
WITH THIS WAVE AND ITS ASSOCIATED SFC LOW BY WED MORNING IN
COMPARISON TO THE ECMWF AND CANADIAN. IN LIGHT OF THE FAST FLOW AND
FAIRLY MARGINAL UPPER JET SUPPORT...THE WEAKER SOLUTIONS ARE
PREFERRED. THIS STILL SUPPORTS A GOOD SHOT OF PRECIP ACROSS SE MI
WED NIGHT ASSOCIATED WITH THE MAIN SURGE OF DEEP LAYER MOISTURE. WET
BULB AFFECTS MAY ALLOW A BRIEF PERIOD OF SNOW TO OCCUR ON THE LEAD
EDGE OF THE PRECIP SHIELD. THE RATE OF LOW LEVEL WARMING IS HOWEVER
EXPECTED TO QUICKLY CHANGE PRECIP OVER TO ALL RAIN. THE EXPECTED
TRACK OF THE SURFACE LOW ACROSS THE NRN LAKES REGION WILL BRING SOME
MILD AIR INTO THE AREA ON WEDNESDAY. THIS WARMING LOOKS TO BE BRIEF
AS A TRANSITION TOWARD A MORE AMPLIFIED FLOW TAKES HOLD BY THE END
OF THE WEEK...FEATURING LONG WAVE TROUGH AMPLIFICATION ACROSS THE
ERN US. THIS SUGGESTS TEMPS FALLING BACK ON THE COOL SIDE OF LATE
MARCH NORMS BY THE END OF THE FORECAST PERIOD.
MARINE...
WINDS WILL VEER TO THE NORTHWEST EARLY THIS MORNING WITH THE PASSAGE
OF A COLD FRONT. ARCTIC AIR WILL THEN FUNNEL INTO THE REGION UNDER A
STRENGTHENING N-NW GRADIENT TODAY INTO TONIGHT. THE GRADIENT FLOW
AND A DEEPENING MIXING LAYER WITHIN THE COLD AIR WILL SUPPORT WIND
GUSTS UP TO 30 KNOTS AT TIMES. SURFACE HIGH PRESSURE WILL BEGIN TO
BUILD ACROSS LOWER MI ON SUNDAY. THIS WILL ACTUALLY SUSTAIN THE N-NW
GRADIENT OVER NRN LAKE HURON...SUGGESTING SOME GUSTY WINDS
PERSISTING OVER THE OPEN LAKE. THE HIGH PRESSURE WILL THEN EXPAND
INTO THE EASTERN GREAT LAKES BY MONDAY...ALLOWING WIND SPEEDS TO
DRAMATICALLY DECREASE.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....CB
SHORT TERM...DRK
LONG TERM....SC
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
310 PM MDT SAT MAR 21 2015
.SYNOPSIS...
DRYING AND WARMING TREND SUNDAY AND MONDAY WITH SOME AFTERNOON
WINDINESS MONDAY. CRITICAL FIRE WEATHER CONDITIONS COULD DEVELOP
MONDAY AFTERNOON FROM THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN
OVER THE NORTHEAST AND EAST CENTRAL PLAINS. SOMEWHAT COOLER
TUESDAY...ALTHOUGH HIGH TEMPERATURES WILL REMAIN ABOVE AVERAGE.
THERE IS POTENTIAL FOR A BRIEF PERIOD OF WETTER WEATHER AROUND THE
MIDDLE OF NEXT WEEK...BUT FORECAST MODELS DIFFER CONSIDERABLY. A
DRYING TREND LOOKS TO RETURN FOR NEXT FRIDAY AND SATURDAY.
&&
.DISCUSSION...
PUNY CONVECTION OVER SOME OF THE NORTHERN...WESTERN AND CENTRAL
HIGH TERRAIN THIS AFTERNOON. KEPT THE SMALL INHERITED POPS FOR THIS
EVENING WITH LITTLE CHANGE...ALTHOUGH BOTH HRRR AND NAM12 MAKE A
CASE FOR ISOLATED CELLS THIS EVENING OVER THE FAR NORTHEAST. GIVEN
THERE/S NOT MUCH GOING ON OVER THE MTS ON THE COLORADO SIDE OF THE
BORDER AT THE MOMENT...THERE/S PROBABLY NOT MUCH CHANCE FOR ONE TO
SCORE A DIRECT HIT ON ANY RAINFALL MEASURING BUCKET.
OTHERWISE...THERE IS POTENTIAL FOR AT LEAST PATCHY FOG IN THE PECOS
VALLEY SOUTH OF INTERSTATE 40 EASTWARD TO THE TEXAS BORDER LATER
TONIGHT AND EARLY SUNDAY...INCLUDING THE CLOVIS/PORTALES
AREA...WHERE 40S DEWPOINTS FORECAST TO REMAIN IN PLACE AND THE MID
TO HIGH LEVEL MOISTURE CLEARS OUT WITH THE DEPARTING LOW/TROUGH.
DEW POINTS DRY OUT SUNDAY AS AN WEAK RIDGE BUILDS OVER THE STATE. A
SFC LEE TROUGH WILL BE ESTABLISHED...AND TEMPERATURES WILL RANGE
FROM AROUND 5 TO NEARLY 20 DEGREES ABOVE AVERAGE...WITH THE GREATEST
DEVIATION FROM NORMAL ACROSS NORTH CENTRAL AND NORTHEAST.
A TREND TOWARD ZONAL FLOW MONDAY...AND COMBINED WITH THE SFC
TROUGH...BREEZY TO WINDY CONDITIONS LOOK TO DEVELOP ESPECIALLY FROM
THE CENTRAL MT CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS.
WIDESPREAD WIND ADVY CRITERIA DOESN/T APPEAR TO BE
LIKELY...HOWEVER...IMPACTS WILL BE FIRE WEATHER RELATED AS HIGHS
WILL SOAR IN TO THE UPPER 70S AND 80S MONDAY AFTERNOON OVER THAT
PART OF THE FORECAST AREA. HIGH TEMPERATURE DEVIATIONS FROM AVERAGE
WILL BE SOMEWHAT SIMILAR TO THOSE OF SUNDAY.
TUESDAY WILL BE SLIGHTLY COOLER AS THE SFC TROUGH AND ASSOCIATED
SHORT WAVE TRACK NORTHEAST OF NEW MEXICO...LEAVING SOME GUSTY
NORTHWEST WINDS TO AFFECT THE CENTRAL MT CHAIN AND ADJACENT
HIGHLANDS.
FOR THE MID TO LATE WEEK PERIOD...THE ECMWF REMAINS THE WETTER
MODEL...COMPARED TO THE GFS...WHICH DEVELOPS 2 SEPARATE FEATURES...A
CUTOFF LOW OVER SOCAL...AND A SHORT WAVE IN THE NW FLOW ALOFT WHICH
CLIPS NORTHEAST NM. GIVEN THE DIFFERENCES...REINED IN POPULATED POPS
FOR WED NIGHT/THURS. FRIDAY AND SATURDAY LOOK DRY...BUT ECMWF DROPS
ANOTHER SHORT WAVE INTO NORTHERN NEW MEXICO SUNDAY...WHILE THE GFS
BOOTS OUT THE SOCAL LOW FARTHER NORTH AND OVER THE STATE. EITHER
WAY...IT LOOKS LIKE SPOTTY PRECIPITATION COULD DEVELOP.
&&
.FIRE WEATHER...
...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ON MONDAY ACROSS MUCH
OF EASTERN NEW MEXICO...
LOW PRESSURE SYSTEM ALOFT CONTINUES TO SWING SOUTH OF NM TODAY WITH
SOME STEADY BATCHES OF LIGHT PRECIPITATION FAVORING THE SOUTHERN
TIER OF THE STATE...MOSTLY OUT OF THE ABQ FIRE WEATHER FORECAST
AREA. HOWEVER...SOME REMNANT INSTABILITY AND MOISTURE IS LEADING TO
DEVELOPMENT OF NEW SHOWERS AND STORMS OVER THE HIGHER TERRAIN OF
CENTRAL NM THIS AFTERNOON. THIS ACTIVITY SHOULD REMAIN FAIRLY
ISOLATED WITH LOW PROBABILITIES FOR ACTUAL WETTING RAINFALL...BUT A
FEW CLOUD TO GROUND LIGHTNING STRIKES COULD OCCUR. DRIER AIR IN THE
MID TO UPPER LEVELS OF THE ATMOSPHERE IS SLOWLY FILTERING INTO THE
STATE FROM THE NORTH NORTHWEST...AND THIS TREND WILL PERSIST
OVERNIGHT. HOWEVER...THE DEWPOINTS NEAR THE SURFACE WILL BE SLOWER
TO RESPOND TO THIS DRYING...THUS ANOTHER NIGHT/MORNING OF EXCELLENT
RH RECOVERY IS ANTICIPATED THROUGH EARLY SUNDAY.
THE REMNANTS OF THE LOW PRESSURE SYSTEM WILL HAVE FULLY EXITED EAST
OF NM ON SUNDAY...GIVING WAY TO A RIDGE OF HIGH PRESSURE. THIS WILL
KEEP THE DRYING TREND GOING...WITH LOW LAYER RH/DEWPOINTS ALSO
QUICKLY RESPONDING DOWNWARD AS DEEP MIXING ENSUES IN AN ABOVE NORMAL
TEMPERATURE REGIME. PRECIPITATION WILL HAVE FULLY ESCAPED AND THE
ENTIRE FORECAST AREA SHOULD EXCEED SEASONAL AVERAGES. A WEAK LEE
SIDE SURFACE TROUGH WILL STRUGGLE TO TAKE SHAPE...BUT WILL NOT FULLY
COME TOGETHER BEFORE DUSK SUNDAY.
THE PATTERN TURNS MORE CRITICAL ON MONDAY AS THE RIDGE ALOFT BREAKS
DOWN AND STRONGER WESTERLY FLOW ALOFT DEVELOPS OVER NM WITH AVERAGE
SPEEDS OF 30-40 MPH IN THE 10000 TO 18000 FT LAYER. THIS WILL BE A
NOTABLE STRENGTHENING OF THESE UPPER LEVEL WINDS THAT HAS YET TO
TRANSFER TO THE SURFACE THUS FAR THIS YEAR. AS THE LEE SIDE SURFACE
CYCLONE BECOMES BETTER ESTABLISHED EXCELLENT MIXING IS
FORECAST...AND BREEZY TO WINDY CONDITIONS WILL ENSUE MONDAY
AFTERNOON WHILE THE WARMER THAN AVERAGE AND DRY CONDITIONS PERSIST.
WIND SPEEDS LOOK TO EXCEED CRITICAL SPEEDS OVER MUCH OF THE
NORTHEASTERN QUADRANT OF NM WHERE RH WILL PLUMMET TO 10 TO 15
PERCENT MONDAY AFTERNOON...AND AFTER FURTHER COLLABORATION ON THE
STATUS OF THE FINE OR 1-HOUR FUELS...BELIEVE THERE WILL BE ENOUGH
FIRE DANGER JUXTAPOSED WITH THE CRITICAL WINDS/RH. THUS...A WATCH
WILL BE HOISTED WITH THIS FORECAST PACKAGE.
A SHORT WAVE TROUGH WILL PASS NORTH OF NM MONDAY NIGHT...KEEPING
WINDS ALOFT STRONG...AND SOME MOUNTAIN WAVE ACTIVITY MAY EVEN CRASH
EAST OF THE SANGRE DE CRISTOS INTO EARLY TUESDAY MORNING. THE
REMAINDER OF TUESDAY SHOULD SEE A DECREASE IN SPEEDS ALOFT WITH
SLIGHTLY COOLER...BUT STILL ABOVE AVERAGE TEMPERATURES PREVAILING.
THE NEXT NOTABLE FEATURE WILL APPROACH ON THURSDAY AS A TROUGH DIVES
SOUTHEAST OUT OF CANADA AND ADDITIONAL ENERGY SEPARATES AND CUTS OFF
ON A TRAJECTORY NEAR OR WEST OF NM. FORECAST MODELS ARE HAVING
DIFFICULTY RETAINING CONTINUITY BETWEEN RUNS AND AMONGST EACH OTHER.
THE IMPACTS FROM THE COLDER AIR AND PRECIPITATION SEEM LESS CERTAIN
ACCORDING TO THE GFS...WHILE THE EUROPEAN MODEL IS MORE ASSERTIVE
WITH BOTH.
52
&&
.AVIATION...
18Z TAF CYCLE
NEW CUMULUS CLOUDS ARE STARTING TO BUBBLE UP OVER THE HIGHER
TERRAIN OF CENTRAL TO WESTERN NEW MEXICO EARLY THIS
AFTERNOON...AND ISOLATED TO SCATTERED SHOWERS ARE EXPECTED TO TAKE
SHAPE INTO THE MID AFTERNOON. ACTIVITY WILL GENERALLY DRIFT FROM
NORTHWEST TO SOUTHEAST AT ABOUT 10 TO 15 MPH WITH GUSTY OUTFLOW
WINDS AND SMALL HAIL POSSIBLE. ANY REDUCTIONS TO
CEILINGS/VISIBILITIES IN DOWNPOURS WILL BE VERY BRIEF. THERE IS
POTENTIAL FOR SOME LOW STRATUS CLOUDS/FOG TO DEVELOP IN THE PECOS
VALLEY AND TOWARD THE EAST CENTRAL PLAINS OF NEW MEXICO LATE
TONIGHT AND INTO EARLY SUNDAY MORNING. LOCALIZED MVFR TO IFR/LIFR
CONDITIONS WOULD BE POSSIBLE...GENERALLY EAST OF A KROW TO KCVN
LINE.
52
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 35 71 34 70 / 0 0 0 0
DULCE........................... 31 67 28 64 / 5 0 5 0
CUBA............................ 34 67 32 65 / 0 0 0 0
GALLUP.......................... 26 69 25 68 / 0 0 0 0
EL MORRO........................ 29 65 28 63 / 5 0 0 5
GRANTS.......................... 27 69 24 67 / 0 0 0 0
QUEMADO......................... 30 66 29 66 / 0 0 0 0
GLENWOOD........................ 39 73 39 72 / 0 0 0 0
CHAMA........................... 22 60 24 57 / 10 0 5 5
LOS ALAMOS...................... 37 67 37 66 / 10 0 0 0
PECOS........................... 33 67 35 64 / 5 0 0 0
CERRO/QUESTA.................... 25 65 26 63 / 5 0 0 5
RED RIVER....................... 24 53 26 51 / 10 5 5 5
ANGEL FIRE...................... 26 59 22 57 / 5 5 0 5
TAOS............................ 28 67 28 65 / 5 0 0 0
MORA............................ 31 66 31 65 / 5 0 0 0
ESPANOLA........................ 37 72 35 71 / 0 0 0 0
SANTA FE........................ 37 66 39 65 / 5 0 0 0
SANTA FE AIRPORT................ 33 70 35 69 / 0 0 0 0
ALBUQUERQUE FOOTHILLS........... 37 72 40 70 / 0 0 0 0
ALBUQUERQUE HEIGHTS............. 38 73 41 72 / 0 0 0 0
ALBUQUERQUE VALLEY.............. 38 76 37 75 / 0 0 0 0
ALBUQUERQUE WEST MESA........... 39 75 38 73 / 0 0 0 0
LOS LUNAS....................... 35 77 35 76 / 0 0 0 0
RIO RANCHO...................... 39 75 38 73 / 0 0 0 0
SOCORRO......................... 40 77 41 77 / 0 0 0 0
SANDIA PARK/CEDAR CREST......... 37 70 39 69 / 0 0 0 0
TIJERAS......................... 34 73 35 71 / 0 0 0 0
MORIARTY/ESTANCIA............... 28 71 31 70 / 0 0 0 0
CLINES CORNERS.................. 34 69 36 68 / 5 0 0 0
GRAN QUIVIRA.................... 33 70 35 70 / 0 0 0 0
CARRIZOZO....................... 35 73 39 72 / 5 0 0 0
RUIDOSO......................... 34 68 40 68 / 10 0 0 0
CAPULIN......................... 33 70 32 71 / 5 0 5 0
RATON........................... 29 73 31 73 / 5 0 5 0
SPRINGER........................ 32 72 33 73 / 5 0 0 0
LAS VEGAS....................... 31 70 34 69 / 0 0 0 0
CLAYTON......................... 36 79 42 79 / 5 0 5 0
ROY............................. 36 75 38 75 / 5 0 5 0
CONCHAS......................... 40 79 40 81 / 0 0 0 0
SANTA ROSA...................... 39 77 41 78 / 0 0 0 0
TUCUMCARI....................... 40 81 40 83 / 0 0 0 0
CLOVIS.......................... 39 77 41 81 / 5 0 0 0
PORTALES........................ 41 76 40 81 / 5 0 0 0
FORT SUMNER..................... 41 79 41 81 / 0 0 0 0
ROSWELL......................... 42 81 42 85 / 10 0 0 0
PICACHO......................... 39 76 40 77 / 10 0 0 0
ELK............................. 37 71 40 72 / 20 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR
THE FOLLOWING ZONES...NMZ103-104-107-108.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1241 PM CDT SAT MAR 21 2015
.UPDATE...
ISSUED AT 1241 PM CDT SAT MAR 21 2015
RADAR RETURNS CONTINUE OVER THE WESTERN COUNTIES BUT LITTLE IS
REACHING THE GROUND. THE RAP AND HRRR HAVE ONLY A VERY LITTLE QPF
ENTERING BENSON COUNTY BUT THE HOPWRF CONTINUES TO SHOW A NARROW
BAND OF ACCUMULATING SNOW REACHING AS FAR EAST AS DEVILS LAKE.
GIVEN THE LOW DEW POINTS AND LACK OF ANYTHING SIGNIFICANT SO
FAR...BACKED OFF A BIT ON POPS BUT KEPT A MENTION OF SNOW GOING
THROUGH THE REST OF THE DAY OVER THE WESTERN CWA. IT WILL BE A
POP BUT LOW QPF SITUATION AT LEAST AS IT APPEARS AT THIS TIME.
UPDATE ISSUED AT 954 AM CDT SAT MAR 21 2015
DESPITE A FAIR AMOUNT OF RADAR RETURNS OVER OUR WESTERN COUNTIES
WEB CAMS AND SFC OBS HAVE BEEN SLOW TO SHOW MUCH REACHING THE
SFC...WHICH MAKES SENSE GIVEN THE DRYNESS OF THE LOWER LAYERS OF
THE ATMOSPHERE. HOWEVER...LEEDS WEB CAMS HAVE SHOWN SOME SIGNS OF
FLAKES...AND THE SHORT RANGE MODELS ARE IN DECENT AGREEMENT ON
BRINGING A NARROW BAND INTO OUR WESTERN COUNTIES. WILL CONTINUE TO
KEEP HIGH POPS IN THE DEVILS LAKE BASIN THROUGH THE REST OF THE
MORNING INTO THE AFTERNOON...BUT WILL KEEP AMOUNTS BELOW AN INCH
UNLESS THERE ARE SIGNS OF BANDING SETTING UP IN THE NEXT FEW
HOURS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 350 AM CDT SAT MAR 21 2015
MODELS IN DECENT AGREEMENT AND WILL USE A BLEND FOR THIS FORECAST.
THE MAIN CHALLENGE WILL BE SNOW CHANCES AND AMOUNTS. SFC RIDGING
WILL BE IN PLACE ACROSS THE REGION WITH A COUPLE WEAK WAVES
INDUCING FRONTOGENESIS AND BANDS OF SNOW. THESE SNOW BANDS WILL
LIKELY BE STRONGEST TO THE WEST...AND WEAKEN AS THEY ENTER THE
DRIER AIRMASS TO THE EAST.
TODAY...THE DEVILS LAKE BASIN AND POTENTIALLY AREAS AROUND WILL
LIKELY RECEIVE SNOWFALL. WENT WITH A HIGH POP/LOW QPF IDEA WITH UP
TO AN INCH OF SNOW. SYNOPTIC SUPPORT IS WEAK SO FEEL FAIRLY
CONFIDENT THAT MOST AREAS WILL REMAIN UNDER AN INCH OF SNOWFALL.
SUNDAY...SIMILAR SCENARIO ALTHOUGH THE RIDGING WILL BE SHIFTED
SLIGHTLY EAST AND SYNOPTIC SUPPORT IS SLIGHTLY STRONGER. CURRENT
SIGNALS INDICATE THIS BAND SETTING UP FROM THE DEVILS LAKE BASIN
INTO THE SOUTHERN VALLEY/WC MN...WITH 1-3 INCHES OF SNOW ACROSS
MOST OF THIS AREA. THE INDICATORS FOR BANDING POTENTIAL ARE
PRESENT ALBEIT WEAK...AND WITH PWATS NEAR 0.5 INCHES WOULD NOT BE
SURPRISED IF A NARROW BAND OF HIGHER AMOUNTS OCCUR (MOST LIKELY
ACROSS THE SOUTHERN FA GIVEN THE CURRENT MODEL SIGNALS).
SUNDAY NIGHT...GOOD AGREEMENT AMONG THE MODELS FOR A STRONGER
UPPER LEVEL WAVE PROPAGATING ALONG THE INTERNATIONAL BORDER
LEADING TO ACCUMULATING SNOWFALL.
TRENDED THE FORECAST TOWARD THE ABOVE IDEAS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT SAT MAR 21 2015
MONDAY...RIDGING BETWEEN SYSTEMS SHOULD LEAD TO SOME SOLAR AND MAX
TEMPS INTO THE 40S MOST AREAS.
TUESDAY-FRIDAY...AN OPEN-WAVE UPPER-AIR TROUGH WILL SPIN UP A
SURFACE LOW PRESSURE SYSTEM THAT WILL START TO AFFECT THE WESTERN
PART OF THE FORECAST AREA WITH A RAIN/SNOW MIX ON TUESDAY. THE
TROUGH DEVELOPS INTO A CLOSED LOW AS IT MOVES EASTWARD WITH THE
SURFACE LOW STRENGTHENING ON WEDNESDAY AND PRECIPITATION FINALLY
EXITING THE AREA ON THURSDAY MORNING. A FAIR-WEATHER HIGH WILL
PREVAIL LATER ON THURSDAY THROUGH EARLY SATURDAY.
DAYTIME TEMPERATURES WILL BE IN THE THIRTIES TUESDAY THROUGH
THURSDAY AND THEN WARMING TO THE FORTIES AFTER THAT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1241 PM CDT SAT MAR 21 2015
BAND OF MID CLOUD WILL CONTINUE OVER THE KDVL-KGFK-KFAR AREA WHILE
WISPY CIRRUS PREVAIL EAST OF THE VALLEY. LIGHT SNOW HEADING TOWARD
DVL BASIN WEAKENING AS IT ENCOUNTERS DRIER AIR AND USED A -SHSN
CHARACTERIZATION FOR PCPN THERE THIS AFTERNOON. LIGHT WINDS FAVORING
NORTHEAST WILL INCREASE A BIT AND SHIFT TO THE EAST OVERNIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/LUKES
AVIATION...WJB
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
526 PM CDT SAT MAR 21 2015
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN
HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE NORTHERN MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES REGION. CLOUDS OFF LAKE SUPERIOR ARE
RETREATING EARLY THIS AFTERNOON AS DRY AIR ALOFT MIXES DOWN.
MEANWHILE...A WIDE SWATH OF MID-CLOUDS IN A
CONFLUENT/FRONTOGENETICAL AREA IS STREAMING SOUTHEAST OVER THE
NORTHERN PLAINS AND POISED TO ARRIVE LATER TODAY. CLOUD TRENDS AND
TEMPS ARE THE MAIN FORECAST CONCERNS OVER THE NEXT 24 HOURS.
TONIGHT...CANADIAN HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
THE STATE OF WISCONSIN. DESPITE THE INCOMING SURFACE HIGH...LAKE
CLOUDS MAY LINGER OVER THE DOOR PENINSULA AS A RESULT OF WINDS
TURNING TO THE EAST AND 925MB TEMPS AROUND -11C. LIGHT NORTHERLY
FLOW AND INCREASING INSTABILITY MAY ALSO BRING LAKE CLOUDS INTO
VILAS COUNTY LATE TONIGHT. OTHERWISE WILL SEE 700MB CONVERGENCE
BRING IN A BAND OF MID-CLOUD ACROSS MUCH OF THE AREA. EDGE THE
NORTHERN EXTENT OF THESE CLOUDS SLIGHTLY FURTHER NORTH BASED ON THE
LATEST GUIDANCE AND SATELLITE TRENDS...AND CONSEQUENTLY...RAISED MIN
TEMPS SLIGHTLY FARTHER NORTH AS WELL. LOWS RANGING FROM THE SINGLE
DIGITS AT LAND O LAKES TO THE MIDDLE 20S SOUTH.
SUNDAY...THE MID-LEVEL CONVERGENCE ZONE WILL SINK SLIGHTLY SOUTH
THROUGH THE DAY WHICH SHOULD LEAD TO CLEARING OVER NORTHEAST
WISCONSIN. ANY LOW CLOUDS OVER N-C WISCONSIN SHOULD MIX OUT WITH
DAYTIME HEATING BY MIDDAY. THEN WILL BE WATCHING AN INVERTED
TROUGH/SHORTWAVE MOVE EAST ACROSS THE NORTHERN MISSISSIPPI VALLEY
DURING THE AFTERNOON. AHEAD OF THESE FEATURES...A BAND OF LIGHT
PRECIP WILL BE DEVELOPING AS IT PUSHES EAST ACROSS CENTRAL MINNESOTA
AND WESTERN WISCONSIN. MOST GUIDANCE INCLUDING THE NAM/SREF/AND
MESOMODELS KEEP PRECIP SOUTHWEST OF THE FORECAST AREA AND THAT
PLACEMENT COINCIDES BETTER WITH THE FRONTOGENETICAL FORCING.
NORTHEAST WINDS WILL KEEP HIGHS COOL AND WILL GO WITH MAX TEMPS
MAINLY IN THE MID TO UPPER 30S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
MAIN CONCERN FOR THIS PERIOD WILL BE SYSTEM SUNDAY NIGHT...A
SECOND SYSTEM TUESDAY NIGHT INTO WEDNESDAY AND BELOW NORMAL
TEMPERATURES FOR THE LATTER HALF OF NEXT WEEK INTO NEXT WEEKEND.
SYSTEM FOR SUNDAY NIGHT APPEARS TO BE LOCKED IN NOW...WITH CHANCES
OF LIGHT SNOW SOUTH OF A KEWAUNEE TO TOMAHAWK LINE. WILL BE FAIRLY
SHARP GRADIENT IN THE SNOW CHANCES WITH THE HIGHEST CHANCES ACROSS
CENTRAL WISCONSIN. SNOWFALL AMOUNTS ACROSS PORTIONS OF PORTAGE...
WOOD..AND WAUSHARA COUNTIES COULD BE AROUND AN INCH. ONLY SNOW
FLURRIES WILL BE SEEN AT GREEN BAY.
EXCEPT FOR A FEW LINGERING FLURRIES MONDAY MORNING ACROSS THE
FAR SOUTH...DRY CONDITIONS WILL PREVAIL MONDAY AFTERNOON INTO
MONDAY EVENING. LATEST DEVELOP TODAY IS THAT SOME OF THE MODELS
ARE PRODUCING LIGHT PRECIPITATION AMOUNTS ACROSS THE NORTH WITH
RETURN FLOW. DID ADD SOME FLURRIES LATE MONDAY NIGHT TO ACCOUNT
FOR THIS SCENARIO.
MAIN SYSTEM STILL ON TRACK FOR TUESDAY NIGHT AND WEDNESDAY.
BOUNDARY/850MB TEMPERATURES STILL PROBLEMATIC WITH PRECIPITATION
TYPES AND SNOW AMOUNTS. ALTHOUGH NOT IN THE FORECAST...COULD BE
A LITTLE SLEET OR FREEZING RAIN MIXED IN AT TIMES ACROSS THE NORTH.
WITH SUCH UNCERTAINTIES IN THE FORECAST...DID NOT ADD TO THE FORECAST
AT THIS TIME. SOME LINGERING LIGHT RAIN OR SNOW SHOWERS COULD LINGER
INTO THURSDAY WITH COLD CYCLONIC FLOW ALOFT.
WESTERN RIDGE WILL BUILD BY THE END OF NEXT WEEK...WHICH WILL LEAD
TO BELOW NORMAL TEMPERATURES INTO NEXT WEEKEND.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 525 PM CDT SAT MAR 21 2015
MAINLY A VFR MID LEVEL CIG WILL INCREASE OVER THE AREA TONIGHT.
MID LEVEL VFR CIGS MAY LINGER OVER PARTS OF CENTRAL WISCONSIN
ON SUNDAY WHILE VFR CIGS WILL LIFT TO HIGH LEVEL CLOUDS
ELSEWHERE.
ON THE MESOSCALE LEVEL...CONVERGENCE ALONG THE LAKE MICHIGAN BREEZE
AND ONSHORE OF THE SHORELINE COUNTIES PRODUCING VERY ISOLATED
MVFR CIGS THROUGH LATE AFTERNOON AND MAY LINGER EARLY EVENING
BEFORE DISSIPATING. THE DISSIPATING OCCURRING DUE TO THE LOSS OF
THE MIXING OF THE WEST TO NORTH WINDS ALOFT AT SUNSET AND LAKE
EFFECT WIND SHIFT MOVING INLAND. PRESENT MOVEMENT SUGGESTS
REACHING GRB AROUND 7 PM...AND ATW BETWEEN 7 AND 8 PM.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN
HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE NORTHERN MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES REGION. CLOUDS OFF LAKE SUPERIOR ARE
RETREATING EARLY THIS AFTERNOON AS DRY AIR ALOFT MIXES DOWN.
MEANWHILE...A WIDE SWATH OF MID-CLOUDS IN A
CONFLUENT/FRONTOGENETICAL AREA IS STREAMING SOUTHEAST OVER THE
NORTHERN PLAINS AND POISED TO ARRIVE LATER TODAY. CLOUD TRENDS AND
TEMPS ARE THE MAIN FORECAST CONCERNS OVER THE NEXT 24 HOURS.
TONIGHT...CANADIAN HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
THE STATE OF WISCONSIN. DESPITE THE INCOMING SURFACE HIGH...LAKE
CLOUDS MAY LINGER OVER THE DOOR PENINSULA AS A RESULT OF WINDS
TURNING TO THE EAST AND 925MB TEMPS AROUND -11C. LIGHT NORTHERLY
FLOW AND INCREASING INSTABILITY MAY ALSO BRING LAKE CLOUDS INTO
VILAS COUNTY LATE TONIGHT. OTHERWISE WILL SEE 700MB CONVERGENCE
BRING IN A BAND OF MID-CLOUD ACROSS MUCH OF THE AREA. EDGE THE
NORTHERN EXTENT OF THESE CLOUDS SLIGHTLY FURTHER NORTH BASED ON THE
LATEST GUIDANCE AND SATELLITE TRENDS...AND CONSEQUENTLY...RAISED MIN
TEMPS SLIGHTLY FARTHER NORTH AS WELL. LOWS RANGING FROM THE SINGLE
DIGITS AT LAND O LAKES TO THE MIDDLE 20S SOUTH.
SUNDAY...THE MID-LEVEL CONVERGENCE ZONE WILL SINK SLIGHTLY SOUTH
THROUGH THE DAY WHICH SHOULD LEAD TO CLEARING OVER NORTHEAST
WISCONSIN. ANY LOW CLOUDS OVER N-C WISCONSIN SHOULD MIX OUT WITH
DAYTIME HEATING BY MIDDAY. THEN WILL BE WATCHING AN INVERTED
TROUGH/SHORTWAVE MOVE EAST ACROSS THE NORTHERN MISSISSIPPI VALLEY
DURING THE AFTERNOON. AHEAD OF THESE FEATURES...A BAND OF LIGHT
PRECIP WILL BE DEVELOPING AS IT PUSHES EAST ACROSS CENTRAL MINNESOTA
AND WESTERN WISCONSIN. MOST GUIDANCE INCLUDING THE NAM/SREF/AND
MESOMODELS KEEP PRECIP SOUTHWEST OF THE FORECAST AREA AND THAT
PLACEMENT COINCIDES BETTER WITH THE FRONTOGENETICAL FORCING.
NORTHEAST WINDS WILL KEEP HIGHS COOL AND WILL GO WITH MAX TEMPS
MAINLY IN THE MID TO UPPER 30S.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 207 PM CDT SAT MAR 21 2015
MAIN CONCERN FOR THIS PERIOD WILL BE SYSTEM SUNDAY NIGHT...A
SECOND SYSTEM TUESDAY NIGHT INTO WEDNESDAY AND BELOW NORMAL
TEMPERATURES FOR THE LATTER HALF OF NEXT WEEK INTO NEXT WEEKEND.
SYSTEM FOR SUNDAY NIGHT APPEARS TO BE LOCKED IN NOW...WITH CHANCES
OF LIGHT SNOW SOUTH OF A KEWAUNEE TO TOMAHAWK LINE. WILL BE FAIRLY
SHARP GRADIENT IN THE SNOW CHANCES WITH THE HIGHEST CHANCES ACROSS
CENTRAL WISCONSIN. SNOWFALL AMOUNTS ACROSS PORTIONS OF PORTAGE...
WOOD..AND WAUSHARA COUNTIES COULD BE AROUND AN INCH. ONLY SNOW
FLURRIES WILL BE SEEN AT GREEN BAY.
EXCEPT FOR A FEW LINGERING FLURRIES MONDAY MORNING ACROSS THE
FAR SOUTH...DRY CONDITIONS WILL PREVAIL MONDAY AFTERNOON INTO
MONDAY EVENING. LATEST DEVELOP TODAY IS THAT SOME OF THE MODELS
ARE PRODUCING LIGHT PRECIPITATION AMOUNTS ACROSS THE NORTH WITH
RETURN FLOW. DID ADD SOME FLURRIES LATE MONDAY NIGHT TO ACCOUNT
FOR THIS SCENARIO.
MAIN SYSTEM STILL ON TRACK FOR TUESDAY NIGHT AND WEDNESDAY.
BOUNDARY/850MB TEMPERATURES STILL PROBLEMATIC WITH PRECIPITATION
TYPES AND SNOW AMOUNTS. ALTHOUGH NOT IN THE FORECAST...COULD BE
A LITTLE SLEET OR FREEZING RAIN MIXED IN AT TIMES ACROSS THE NORTH.
WITH SUCH UNCERTAINTIES IN THE FORECAST...DID NOT ADD TO THE FORECAST
AT THIS TIME. SOME LINGERING LIGHT RAIN OR SNOW SHOWERS COULD LINGER
INTO THURSDAY WITH COLD CYCLONIC FLOW ALOFT.
WESTERN RIDGE WILL BUILD BY THE END OF NEXT WEEK...WHICH WILL LEAD
TO BELOW NORMAL TEMPERATURES INTO NEXT WEEKEND.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1237 PM CDT SAT MAR 21 2015
SPOTTY MVFR CIGS OVER FAR NORTH-CENTRAL AND NORTHEAST WISCONSIN WILL
LIFT TO VFR EARLY THIS AFTERNOON AS DRIER AIR IS MIXED DOWNWARD.
THEN WILL SEE AN AREA OF MID-CLOUDS FROM THE NORTHERN PLAINS MOVE
INTO THE REGION THIS EVENING. NO PRECIPITATION IS EXPECTED THROUGH
THE END OF THE TAF PERIOD...AND DIMINISHING WINDS SHOULD LEAD TO
DECENT FLYING WEATHER TONIGHT INTO SUNDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC