Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/07/13
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
150 PM MST FRI JUL 5 2013
.SYNOPSIS...
HIGH PRESSURE WILL GRADUALLY POSITION ITSELF ACROSS THE REGION
THROUGH THIS WEEKEND. MONSOON ACTIVITY WILL LIKELY REMAIN CONFINED
TO THE HIGHER TERRAIN EAST OF PHOENIX THROUGH EARLY NEXT WEEK...WITH
LITTLE CHANCE OF RAIN ACROSS THE DESERTS. A GRADUAL RETURN TO A MORE
FAVORABLE MONSOON PATTERN IS POSSIBLE BY LATE NEXT WEEK.
&&
.DISCUSSION...
ACROSS SOUTH-CENTRAL AZ...TEMPERATURES ARE GENERALLY RUNNING 5 TO 10
DEGREES COOLER THAN THEY WERE THIS TIME YESTERDAY. THE EXTENSIVE
CLOUD COVER FROM THIS MORNING IS DISSIPATING BUT CONTINUES TO RESULT
IN CONSIDERABLE CIN ACROSS THE AREA. FURTHER SOUTH...STRONG
CONVECTION HAS INITIATED ACROSS PORTIONS OF SE AZ IN AN AREA
CHARACTERIZED BY MLCAPES > 1000 J/KG. WV IMAGERY AND STREAMLINE
ANALYSIS SUGGEST THAT ACTIVITY IS ALSO BEING FORCED BY AN INVERTED
TROUGH ACROSS NORTHERN SONORA CIRCULATING AROUND THE AZ ANTICYCLONE.
HI-RES CONVECTIVE ALLOWING MODELS OFFER A WIDE RANGE OF POSSIBLE
SOLUTIONS...THOUGH GIVEN WHAT IS OCCURRING NOW...THE SPC RAP AND U
OF A WRFS APPEAR TO PRESENT THE MOST PLAUSIBLE OUTCOME. FORECAST IS
BASED ON A SCENARIO IN WHICH INHIBITION REMAINS STRONG ACROSS THE
PHOENIX AREA AND ISOLATED CONVECTION IS FAVORED ACROSS PINAL COUNTY
AND INTO SOUTHERN GILA COUNTY. LATEST AIRCRAFT SOUNDING FROM KPHX
LENDS CREDENCE TO THIS...SHOWING A WARM LAYER NEAR 700 MB AND A
CONVECTIVE TEMPERATURE OF 108 DEGREES...WHICH IS OUT OF REACH. MAIN
IMPACT ACROSS THE PHOENIX AREA WILL AGAIN BE THE POTENTIAL FOR AN
OUTFLOW BOUNDARY WITH BLOWING DUST...MAINLY SOUTH AND EAST OF QUEEN
CREEK.
&&
.PREVIOUS DISCUSSION...
UPPER LEVEL HIGH CONTINUES ITS TREK EASTWARD ON SATURDAY WITH THE
UPPER FLOW TAKING ON A SOUTHWESTERLY COMPONENT ACROSS THE DESERT
SOUTHWEST. CONSEQUENTLY...MOISTURE SHIFTS EASTWARD WITH MIXING
RATIOS DROPPING TO AROUND 7 G/KG SATURDAY AND 6 K/KG SUNDAY/MONDAY.
LIKEWISE...INSTABILITY ACROSS THE DESERTS IS VIRTUALLY NONEXISTENT
THIS WEEKEND INTO EARLY NEXT WEEK. NOT SAYING THE AREA WILL BE
COMPLETELY DEVOID OF STORMS /SOME MOISTURE AND INSTABILITY REMAIN IN
PLACE ACROSS THE MOUNTAINS EAST OF PHOENIX/...BUT THE LIKELIHOOD OF
RAIN OUTSIDE OF SOUTHERN GILA COUNTY LOOKS QUITE LOW. POPS WERE
ALREADY A FEW PERCENT BELOW CLIMO ACROSS THE DESERTS AND I WILL
CONTINUE THAT TREND. GUSTY/DUSTY OUTFLOWS REMAIN A POSSIBILITY ON
SATURDAY BUT IT APPEARS EVEN THAT THREAT WILL DIMINISH LATER THIS
WEEKEND INTO EARLY NEXT WEEK.
THE 00Z GFS AND ESPECIALLY THE 00Z EUROPEAN INDICATE AN UPPER LEVEL
PVD WILL MAKE ITS WAY THROUGH NORTHERN MEXICO BY THE MIDDLE OF NEXT
WEEK AND QUICKLY TURN THE FLOW AROUND TO A MORE FAVORABLE SE
DIRECTION...ALL WHILE ADVECTING MORE MOISTURE INTO THE AREA. IF THE
EUROPEAN IS TO BE TAKEN AT FACE VALUE...THE MONSOON SHOULD BE WELL
UNDERWAY ACROSS THE REGION BY WEDNESDAY/THURSDAY GIVEN ITS MORE
NORTHERLY TRACK WITH THE UPPER LEVEL PVD. THE GFS ON THE OTHER HAND
KEEPS THE UPPER LOW SOUTH OF THE BORDER. WHILE IT ADVECTS SOME
MOISTURE NORTHWARD...IT KEEPS PRECIP CHANCES CONFINED TO EASTERN
ARIZONA AND SUGGESTS MORE OF A BLOWING DUST THREAT. LAST SUMMER THE
EUROPEAN WAS CONSISTENTLY TOO MOIST SO IM HESITANT TO BUY INTO IT
100 PERCENT...BUT I WILL SHOW HIGHER THAN NORMAL POPS FOR WEDNESDAY
THROUGH FRIDAY GIVEN THE FAVORABLE PATTERN FROM BOTH MODELS. EVEN SE
CA COULD GET IN ON THE ACTION ONE OF THOSE DAYS WITH STRONG FLOW UP
THE GULF OF CALIFORNIA.
TEMPS OVER THE NEXT WEEK WILL TAKE A BRIEF RUN ABOVE THE 110 DEGREE
MARK THIS WEEKEND /COURTESY OF DRIER BL DEWPOINTS/...FOLLOWED BY A
SLIGHT DIP BACK TOWARD NORMAL AS INCREASED MOISTURE MOVES INTO THE
AREA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA AND KSDL...
SCT-BKN MID/HIGH CLOUDS WILL AFFECT CENTRAL ARIZONA SITES THROUGH
THE TAF PERIOD. THERE IS A REMOTE CHANCE FOR SOME VIRGA EARLY THIS
MORNING...ESPECIALLY AT SKY HARBOR...AS DEBRIS CLOUDS FROM
THUNDERSTORMS THAT DEVELOPED OVER NORTHERN ARIZONA LAST NIGHT DRIFT
OVER THE AREA. THUNDERSTORMS DEVELOPMENT THIS AFTERNOON IS EXPECTED
TO REMAIN WELL NORTH AND EAST OF THE TERMINALS...BUT THERE IS AN
OUTSIDE CHANCE FOR SOME GUSTY WINDS AND BLOWING DUST AS OUTFLOWS
FROM THESE STORMS MOVE INTO THE VALLEY...WHICH WILL NOT BE INCLUDED
IN THE TAFS...FOR NOW. WINDS ARE EXPECTED TO BECOME EASTERLY FOR A
TIME THIS MORNING...BUT THEN ARE EXPECTED TO RAPIDLY BECOME WESTERLY
BY LATE THIS MORNING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
ONLY SCT-BKN HIGH CLOUDS WILL AFFECT SOUTHEAST CALIFORNIA TERMINALS
THROUGH THE TAF PERIOD. SFC WINDS WILL GENERALLY FAVOR A SOUTHERLY
TO SOUTHEASTERLY DIRECTION AT BOTH TERMINALS. WINDS LIKELY WILL
BECOME GUSTY AT TIMES ALONG THE LOWER COLORADO RIVER VALLEY FRIDAY
AFTERNOON AND EVENING...WITH SOMEWHAT LIGHTER WINDS AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
A WARMING TREND ENSUES SUNDAY AND CONTINUES INTO EARLY NEXT WEEK.
THUNDERSTORM ACTIVITY WILL BECOME CONFINED TO JUST A FEW SPOTS OVER
THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX FROM SUNDAY ONWARD INTO
TUESDAY AS A DRIER SOUTHWESTERLY FLOW DEVELOPS OVER THE REGION. SOME
INCREASE IN THUNDERSTORM ACTIVITY IS THEN EXPECTED ON WEDNESDAY AND
THURSDAY AS THE FLOW ALOFT BECOMES MORE SOUTHERLY...AND BEGINS TO
IMPORT MOISTURE BACK INTO THE REGION. MINIMUM HUMIDITIES ARE
EXPECTED TO FALL FROM THE MID AND UPPER TEENS ON SUNDAY DOWN INTO
THE UPPER SINGLE DIGITS AND LOW TEENS ON MONDAY AND TUESDAY...THEN
RECOVER BACK INTO THE UPPER TEENS AND LOW 20S BY THURSDAY. WINDS
WILL BE LOCALLY BREEZY DURING THE AFTERNOON AND EVENING HOURS
THROUGH THE FORECAST PERIOD...WITH DIRECTIONS FAVORING THE WEST.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...LEINS
AVIATION...PERCHA
FIRE WEATHER...PERCHA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
734 PM MDT SAT JUL 6 2013
.UPDATE...
ISSUED AT 725 PM MDT SAT JUL 6 2013
UPDATED TO BUMP UP POPS ACROSS THE FAR EASTERN PLAINS WHERE
CLUSTER OF SHOWERS/THUNDERSTORMS CONTINUES. 23Z HRRR SLOWLY SHIFTS
THIS EASTWARD AND HANGS ON TO SOME SPOTTY QPF NEAR THE EASTERN
BORDER AFTER MIDNIGHT. IT ALSO DEVELOPS ANOTHER BAND OF
SHOWERS/EMBEDDED THUNDERSTORMS ACROSS THE CENTRAL MOUNTAINS WHICH
SHIFTS INTO THE SOUTHEAST MOUNTAINS AROUND 06Z BEFORE DIMINISHING
AS IT HEADS EASTWARD ACROSS THE SOUTHERN I-25 CORRIDOR AFTER 10Z.
SO FAR...HRRR SEEMS OVERDONE WITH THIS LATER BATCH OF
CONVECTION...BUT HAVE INTRODUCED SOME ISOLATED POPS OVER THE
MOUNTAIN AREAS THROUGH 08Z TO ACCOUNT FOR THE POSSIBILITY OF
LINGERING CONVECTION WITHIN MOISTURE PLUME. WILL WAIT FOR 00Z
NAM12 RUN TO ARRIVE BEFORE EXTENDING POPS THROUGH THE NIGHT FOR
MOST AREAS AS HRRR SUGGESTS. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM MDT SAT JUL 6 2013
...EARLY GLIMPSE OF THE MONSOON UNDERWAY...
EARLY MONSOONAL AIRMASS OVER SOUTHERN COLORADO THIS WEEKEND WITH
SURFACE DEWS NOW IN THE 40S AND 50S PRETTY MUCH ANY WHICH WAY YOU
LOOK. ALOFT...PLENTY OF MID/HIGH LEVEL MONSOON MOISTURE CIRCULATING
AROUND LARGE MEW MEXICO HIGH PRESSURE AREA. VERY LITTLE COLD AIR
ALOFT ASSOCIATED WITH LARGE HIGH SETTING THE STAGE FOR TYPICAL
DIURNAL AFTERNOON AND EVENING THUNDERSTORM ACTIVITY PRODUCING MOSTLY
RAIN AND MAYBE A LITTLE BIT OF SMALL HAIL...WITH OTHER THREATS
INCLUDING LIGHTNING AND LOCALLY GUSTY WINDS UP TO AROUND 50 MPH.
MONSOONAL MOISTURE IS NOT REAL GREAT YET...WITH PRECIPITABLE WATERS
RANGING FROM A SOUTHERN COLORADO MAX OF A LITTLE OVER AN INCH ACROSS
THE SOUTHEAST TIP OF BACA COUNTY TO A MIN AROUND 3 QUARTERS OF AN
INCH ACROSS THE NORTHWEST TIP OF LAKE COUNTY. BUT...SURELY BETTER
THAN A COUPLE DAYS AGO...AND ADEQUATE FOR SOME LOCALLY HEAVY
RAINERS. THERE IS CERTAINLY ENOUGH WATER IN THE ATMOSPHERE FOR
CONCERN OVER SOME OF THE NEWER AREA BURN SCARS INCLUDING THE
WALDO...EAST PEAK AND WEST FORK SCARS. VIGILANCE MUST CONTINUE IN
THESE AREAS FOR THE FORESEEABLE FUTURE...STARTING WITH THIS
AFTERNOON AND EVENING.
AS IN RECENT DAYS...MOST THUNDERSTORM ACTIVITY SHOULD DIE DOWN
ACROSS THE AREA BY AROUND 04Z OR SO...WITH CONVECTIVE DEBRIS
LINGERING AND GRADUALLY DISSIPATING AFTER THAT. FEEL THAT MOST
ACTIVITY WILL BE COMPLETELY OVER BY MIDNIGHT...ALTHOUGH THERE COULD
BE A FEW STRAGGLERS THROUGH THE NIGHT...COVERING LESS THAN ONE
PERCENT OF THE FORECAST AREA. LW
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM MDT SAT JUL 6 2013
...MONSOON SEASON IS UPON US...
LOOKS LIKE A FAIRLY NORMAL SUMMER PATTERN WILL BE WITH US FOR THE
COMING WEEK. FORECAST TEMPS AND PRECIP WILL BE INFLUENCED BY THE
OVERALL PATTERN...INCLUDING THE POSITION OF THE RIDGE AND H5 HIGH
OVER THE SW U.S. THE UPPER HIGH WILL START OFF OVER THE 4 CORNERS
REGION ON MONDAY AND TUESDAY. THIS CAN BE A FAVORABLE MONSOONAL
PATTERN...BUT IN THIS PARTICULAR CASE THE UPPER RIDGE WILL BE
FLATTENED BY A SHORT WAVE MOVING THROUGH SW AND SRN CANADA...SO
UPPER WINDS WILL BE GENERALLY WESTERLY AND BRINGING RELATIVELY DRY
AIR IN FROM THE W AND SW. HOWEVER...THE SHORTWAVE COULD SPARK A FEW
HIGH BASED STORMS...PARTICULARLY OVER THE ERN MTS AND PLAINS LATE
MONDAY AND AGAIN ON TUESDAY.
TUESDAY NIGHT...A WEAK FRONT ASSOCIATED WITH THE SHORT WAVE NOW
MOVING INTO THE GREAT LAKES REGION WILL PUSH OVER ERN CO. THE UPPER
HIGH WILL HAVE MIGRATED SLIGHTLY EWD INTO NW NM. THIS WILL SET THE
STAGE FOR AN UP-TICK IN PRECIP ON WED...ESPECIALLY OVER THE MTS BUT
EXTENDING EWD ONTO THE PLAINS BY WED EVE.
THURSDAY...THE MONSOON PLUME RETURNS TO WRN CO AS THE UPPER HIGH
CONTINUES TO DRIFT SLIGHTLY TO THE W OVER NRN NM. A FAIRLY ROBUST
MOISTURE PLUME THEN LOOKS TO AFFECT THE AREA FRI AND THROUGH THE
WEEKEND. AT THIS TIME...IT LOOKS LIKE THE BULK OF THE HEAVIER
CONVECTION WILL BE OVER THE CENTRAL MTS...WHICH COULD BRING AN
INCREASED THREAT OF FLASH FLOODING TO THE MT AREAS...AND
PARTICULARLY THE WEST FORK BURN...THROUGH THE WEEKEND.
DAYTIME HIGH TEMPS WILL BE A BIT TRICKY TO FORECAST THIS COMING
WEEK. THE H5 HEIGHTS AND H7 TEMPS JUSTIFY HIGH TEMPS IN THE UPPER
90S OR EVEN LOW 100S FOR SEVERAL DAYS OVER THE LOWER ARKANSAS AND
ERN PLAINS. AT THIS TIME...SINCE THE MONSOONAL MOISTURE APPEARS TO
AFFECT MAINLY THE CENTRAL MTS...IF IT STAYS DRY ENOUGH THESE HIGH
TEMPS WILL BE REALIZED...AND THIS IS WHERE THE FORECAST TREND HAS
BEEN FOR THE DAILY HIGHS. HOWEVER...IT DOES APPEAR THAT AT LEAST
MODEST MID LEVEL MOISTURE WILL BE TRAPPED UNDER THE RIDGE...AND
COULD BRING AT LEAST ISOLD TO SCT CONVECTION OVER THE PLAINS EACH
DAY. IF THIS HAPPENS...THEN THE DAY TIME HIGHS COULD BECOME A RACE
BETWEEN REALIZING THE WELL MIXED VALUES DOWN FROM H7-H5...AND THE
DEVELOPMENT OF EARLY AFTERNOON THUNDERSTORMS...WHICH COULD BRING
DOWN TEMPS IN A HURRY FOR THE PLAINS. HOPEFULLY...THE PLUME WILL
SHIFT FAR ENOUGH E AT SOME POINT THAT MORE DEEP MOISTURE CAN MOVE
OVER THE PLAINS. ROSE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 245 PM MDT SAT JUL 6 2013
IN GENERAL...VFR CONDITIONS WILL CONTINUE AT THE KALS...KCOS AND
KPUB TAF SITES THROUGH SUNDAY AS THE AREA REMAINS IN HIT OR MISS
EARLY MONSOON DIURNAL THUNDERSTORM PATTERN. HOWEVER... ISOLATED TO
SCATTERED THUNDERSTORM ACTIVITY WILL BE CAPABLE OF IMPACTING THE
TAF SITES AT TIMES...ESPECIALLY DURING THE AFTERNOON AND EARLY
EVENING HOURS. THE MOST INTENSE ACTIVITY FOR THE MOUNTAINS AND
HIGH VALLEYS SHOULD GENERALLY RUN FROM 18-00Z. FOR THE
PLAINS...THE MOST INTENSE ACTIVITY SHOULD GENERALLY OCCUR 21Z-03Z.
PRIMARY STORM THREATS INCLUDE LIGHTNING...HEAVY RAIN...ERRATIC
WIND GUSTS TO AROUND 50 MPH...AND SMALL HAIL. LW
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KT
SHORT TERM...LW
LONG TERM...ROSE
AVIATION...LW
AREA FORECAST DISCUSSION
NWS TAUNTON MA
733 PM EDT SAT JUL 6 2013
.SYNOPSIS...
OFFSHORE BERMUDA HIGH GRADUALLY WEAKENS ALLOWING FOR A RETURN OF
DISTURBED WEATHER INTO THE BEGINNING OF NEXT WEEK. THERE WILL BE
A CHANCE OF THUNDERSTORMS MOST DAYS THROUGH THE FORECAST PERIOD.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
730 PM UPDATE...ONLY MINOR TWEAKS NEED TO THE FORECAST THIS
EVENING. ISOLATED SHOWERS ALONG A SEABREEZE BOUNDARY HAVE
DISSIPATED. MAINLY CLEAR SKIES THIS EVENING...WITH SOME MID-LEVEL
CLOUDS ARRIVING LATER TONIGHT. BROUGHT ALL NEAR-TERM CONDITIONS
PRESENT WITH OBSERVED TRENDS.
PREVIOUS DISCUSSION...
INTO THIS EVENING...
WEAK CONVERGENCE BOUNDARY PRESSING SOUTH ACROSS SOUTHERN NEW
ENGLAND ACTING AS A FOCUS OF A LINE OF SCATTERED SHOWERS. HEAVY
RAIN LOOKS TO BE THE MAIN THREAT. THIS BOUNDARY APPEARS TO BE A
PUSH AHEAD OF A WEAK WAVE DISTURBANCE AND DRY SINKING AIRMASS TO
THE REAR /NOTABLY THE DIMINISHING CUMULUS FIELD IN WAKE ACROSS
UPSTATE NY AND THE DRY PUNCH BENEATH H5 IN THE 12Z BUFFALO UPPER-
AIR SOUNDING/.
WILL CONTINUE WITH SLIGHT CHANCE POPS OF SHOWERS AND T-STORMS AS
INSTABILITY IS PLENTIFUL IN A REGION OF WEAK UNIDIRECTIONAL SHEAR.
THE HRRR HAS BEEN DOING THE BEST IN FORECASTING THIS SITUATION.
TEMPERATURE AND DEWPOINT TRENDS REMAIN ON TRACK AND WILL HOLD
WITH PRESENT HEAT ADVISORIES. MANY LOCATIONS ARE REPORTING
TEMPERATURES OF 90 DEGREES FOR A 3RD OR 4TH STRAIGHT DAY...PUTTING
MUCH OF SOUTHERN NEW ENGLAND BY DEFINITION IN A HEAT WAVE.
TONIGHT...
OFFSHORE BERMUDA HIGH CONTINUES TO UNDERGO A GRADUAL WEAKENING
ALLOWING THE LONGWAVE FLOW PATTERN TO SHIFT SOUTH AND EAST. AS A
RESULT...MID- TO HIGH-LEVEL CLOUDS WILL FILTER ACROSS THE
REGION...AND COUPLED WITH THE MOIST AIRMASS AT THE SURFACE WILL
MAKE FOR ANOTHER MILD EVENING WITH MINS AROUND THE UPPER 60S. A
DRY NIGHT WITH WESTERLY FLOW. GREATEST FOG THREAT WILL BE ALONG
THE SOUTH SHORE...ESPECIALLY OVER NANTUCKET.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY...
WITH THE TROUGH DIGGING THROUGH THE OHIO RIVER VALLEY REGION...SUBSEQUENT
WARM-AIR ADVECTION ALONG AND AHEAD HOLDS THE RIDGE STEADY ACROSS
NEW ENGLAND. CONFIDENCE OF THE WEATHER OUTCOMES IS WAVERING. THE
TIMING OF THE TROUGH IS KEY...WHETHER MID- TO UPPER-LEVEL
DIFFLUENCE AHEAD OF THE TROUGH GETS INTO NEW ENGLAND. OTHERWISE IT
APPEARS RIDGING PREVAILS AS H5 TEMPERATURES SLIGHTLY WARM
DIMINISHING MID-LEVEL LAPSE RATES. ACTIVITY MAY BE SUPPRESSED
ACROSS THE REGION KEEPING IT WEST.
ASSUMING SHOWERS AND THUNDERSTORMS DO DEVELOP...THE GREATEST
LIKELIHOOD OF WHICH WILL BE ACROSS NY/PA FOCUSED ALONG THE SURFACE
FRONTAL BOUNDARIES...WESTERN PORTIONS OF NEW ENGLAND ARE UNDER
THE GREATEST THREAT...MAINLY HEAVY RAIN /PWATS AROUND 1.5 - 1.75
INCHES/ AND GUSTY WINDS. THE WARM/MOIST AIRMASS WILL REMAIN IN
PLACE ALLOWING FOR PLENTY OF INSTABILITY WITH DAYTIME DIURNAL
MIXING. WITH THIN CAPE COUPLED WITH MINOR UNIDIRECTIONAL WESTERLY
SHEAR...ANTICIPATING PULSE TO MULTI-CELLULAR CONVECTION WHICH MAY
NOT SUSTAIN WELL OR LONG ENOUGH. LOW CONFIDENCE AS TO A SEVERE
WEATHER THREAT...THE BETTER DYNAMICS AND LIFT SIT NORTH AND WEST
OF THE REGION. WILL BE MONITORING FOR ANY SURFACE CONVERGENCE
BOUNDARIES AND ALONG THE WESTERN SLOPES OF HIGHER TERRAIN AS AN
AID TO INVIGORATING POTENTIAL WEATHER.
HIGH TEMPERATURES ONCE AGAIN AROUND THE LOW 90S...FOR SOME LOCATIONS
THIS WILL BE THE 5TH DAY IN A ROW. WITH THE EXPECTED CLOUD COVER
TEMPERATURES ARE ANTICIPATED TO BE A DEGREE OR TWO LOWER WHICH
WILL ALLOW FOR HEAT INDEX VALUES TO REMAIN BELOW HEAT ADVISORY
THRESHOLDS. WILL ALLOW THE EVENING CREW TO TAKE A LOOK AT
TEMPERATURES ACCORDINGLY AND EVALUATE WHETHER HEADLINES WILL BE
NECESSARY. FOR NOW A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO
ADDRESS THE ANTICIPATED HEAT FOR SUNDAY.
SUNDAY NIGHT...
OHIO VALLEY REGION TROUGH PUSHES WEST INTO THE CENTRAL
APPALACHIANS RESULTING IN INCREASING DIFFLUENCE ALOFT OVER NEW
ENGLAND LATE IN THE PERIOD. THERE REMAINS SOME TIMING AND
INFLUENCE OF THE TROUGH ON THE REGIONS WEATHER. IT APPEARS THAT
MID-LEVEL ENERGY LAGS THE SYSTEM AND CONSEQUENTIALLY IT COULD
REMAIN QUIET AFTER ALL DAYTIME SHOWER AND THUNDERSTORM ACTIVITY
DIMINISHES /THAT IS IF IT INITIATES/. HAVE KEPT THE GREATEST
CHANCES FOR WEATHER ALONG THE NORTH AND WEST PORTIONS OF THE
FORECAST AREA. SHOULD BE A LOT OF CLOUDS WITH INCREASING INFLUENCE
OF THE RIGHT-ENTRANCE REGION OF THE UPPER-LEVEL JET. ANOTHER MILD
NIGHT WITH MINS AROUND THE 70 DEGREE MARK UNDER WESTERLY FLOW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* WARM AND HUMID CONDITIONS CONTINUE THROUGH MOST OF NEXT WEEK
* SHOWERS AND THUNDERSTORMS POSSIBLE EACH DAY...MAINLY INTERIOR
OVERVIEW AND MODEL PREFERENCES...06/12Z GUIDANCE CONTINUES TO
EXHIBIT DECENT AGREEMENT WITH THEIR HANDLING THE SYNOPTIC FEATURES
THROUGH THIS PORTION OF THE FORECAST. THERE ARE SOME DISAGREEMENTS
WITH TIMING...WHICH LEADS TO ONLY AN AVERAGE CONFIDENCE. 06/12Z
ECMWF REMAINS SLOWER TO PROGRESS A MID-LEVEL TROUGH EAST THAN THE
GFS...BUT PERHAPS A BIT TOO SLOW.06/12Z GFS IS PERHAPS A LITTLE
TOO FAST BUT DOES HAVE DECENT SUPPORT FROM THE GEFS MEAN. THE
06/12Z NAM LOOKED LIKE A GOOD COMPROMISE TIMING THROUGH TUESDAY.
THEREAFTER...USED A CONSENSUS BLEND FOR THE TIMING AS DID NOT HAVE
ENOUGH CONFIDENCE IN ANY ONE PARTICULAR MODEL SOLUTION.
ESSENTIALLY...THE PATTERN LOOKS TO BE FAIRLY UNSETTLED THROUGH MOST
OF NEXT WEEK AS THE BERMUDA HIGH SLOWLY MOVES EAST.
DETAILS...
MONDAY INTO TUESDAY...A WEAK SURFACE TROUGH AND MID-LEVEL SHORTWAVE
WILL LIKELY SPARK CONVECTION MONDAY. THE ISSUE WILL BE HOW MUCH
INSTABILITY CAN BE GENERATED WITH A COLD POOL MOVING NEARBY. THERE
SHOULD STILL BE SOME PROTECTIVE RIDGING TOWARD THE CAPE AND ISLANDS.
LAPSE RATES SHOULD BE MEAGER AT ABOUT 5.5-6.0C/KM. SHOULD THE SUN
BREAK OUT...ML CAPE VALUES COULD APPROACH 1000-1500J/KG...AND SHEAR
MAGNITUDES APPROACH 35-40 KT. THEREFORE...HOW STRONG THE CONVECTION
IS WILL BE DEPENDENT ON CLOUD COVER INITIALLY...BUT THERE IS ENOUGH
SUPPORT FOR ANY CONVECTION THAT DOES FORM TO BECOME SOMEWHAT
ORGANIZED. HEAVY RAIN STILL THE BIGGEST THREAT THOUGH WITH PWAT
VALUES APPROACHING 2.0 INCHES...SO WILL CONTINUE TO MENTION THIS IN
WX WITH ANY THUNDERSTORMS.
NOT OUT OF THE QUESTION MORE STORMS COULD FIRE ON TUE...BUT A WEAK
MID LEVEL RIDGE MAY BE ENOUGH TO FORCE BEST INSTABILITY/SHEAR AND
FOCUS FOR LIFT TO OUR NORTH DURING THE DAY.
WED INTO EARLY NEXT WEEKEND...
A BROAD MID-LEVEL TROUGH IS EXPECTED TO DEEPEN IN VICINITY OF THE
GREAT LAKES THROUGH THIS PERIOD ALLOWING A LOW PRESSURE TO PASS WELL
NORTH AND WEST OF OUR REGION. A SFC WARM FRONT WILL APPROACH AND
LIKELY CROSS THE REGION WEDNESDAY INTO EARLY THURSDAY. THIS COULD
PROVIDE ANOTHER FOCUS FOR MORE WIDESPREAD SHOWERS AND THUNDERSTORMS.
THE TIMING OF THE COLD FRONT ASSOCIATED WITH THIS LOW PRESSURE IS
STILL A BIT IN QUESTION AS IT WILL BE DETERMINED ON HOW AMPLIFIED
THE UPPER LEVEL PATTERN GETS BY NEXT WEEK. FOR NOW WILL ERR TOWARD
THE ENSEMBLE MEANS WHICH SUGGEST FRIDAY OR FRIDAY NIGHT. IN ANY
CASE...ANOTHER THREAT FOR THUNDERSTORMS AND RAINFALL.
TEMPERATURES DURING THIS PERIOD SHOULD BE SEASONABLE TO SLIGHTLY
ABOVE NORMAL. IT WILL LIKELY REMAIN VERY HUMID HOWEVER.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /INTO SUNDAY NIGHT/...MODERATE CONFIDENCE.
WINDS BECOME LIGHT THIS EVENING WITH SCT-BKN MID-HIGH CIGS. MAIN
CONCERN IS FOG ALONG THE SOUTH-SHORE. WENT WITH PERSISTENCE OF
TRENDS KEEPING KACK AT MVFR VSBYS WITH IFR CIGS WHICH WAS THE
OUTCOME LAST NIGHT.
A REPEAT OF SATURDAY IS EXPECTED SUNDAY...THOUGH THE CHANCES FOR
SHRA/TSRA INCREASE. GREATER CONFIDENCE IS UPON WESTERN INTERIOR
AND THOSE TERMINALS NORTH OF THE MASS-PIKE BEING IMPACTED. HAVE
PREVAILED VCSH FOR KBDL. WESTERLY WINDS GUSTING UP TO AROUND 20
KT. ACTIVITY SHOULD PREVAIL INTO THE EVENING PERIOD FOR THE SAME
TERMINALS IMPACTED SUNDAY.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. VCSH SUNDAY AFTERNOON WITH
THE EXPECTATION FOR SHRA/TSRA TO POTENTIALLY IMPACT THE TERMINAL.
OUTLOOK...MONDAY THROUGH THURSDAY...
HIGH CONFIDENCE IN OVERALL TRENDS...LOWER CONFIDENCE IN THE TIMING
OF ANY LOWER CATEGORIES THROUGH NEXT WEEK. LITTLE CHANGE IN FORECAST.
MAINLY VFR. THERE IS A LOW TO MODERATE PROBABILITY OF SHOWERS AND
THUNDERSTORMS AND ACCOMPANYING MVFR/IFR CONDITIONS EACH AFTN/EVE.
FOG IS LIKELY TO DEVELOP MOST NIGHTS...WITH THE HIGHEST
PROBABILITY OF THIS HAPPENING ALONG THE SOUTH COAST. THIS WILL
LIMIT CIGS AND VSBYS TO IFR/MVFR AT TIMES.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /INTO SUNDAY NIGHT/...HIGH CONFIDENCE.
WINDS AND SEAS SHOULD REMAIN BELOW SCA THRESHOLDS THROUGH SUNDAY
NIGHT. WEST-SOUTHWEST WINDS WILL LIKELY GUST AROUND 20 KNOTS AT
TIMES...ESPECIALLY ALONG THE SOUTH-SHORE...CAPE AND ISLANDS. FOG
MAY BE AN ISSUE WITH VISIBILITIES DOWN TO A QUARTER MILE OR LESS.
GREATEST CONFIDENCE IS FOR FOG TO IMPACT NANTUCKET.
OUTLOOK...MONDAY THROUGH THURSDAY...
MODERATE CONFIDENCE THROUGH THE PERIOD.
PERSISTENT WEST TO SOUTHWEST WINDS AND LINGERING SWELL WILL ALLOW
SEAS TO REACH ABOUT 5 FT LATE MONDAY INTO TUESDAY ACROSS THE COASTAL
WATERS SOUTH AND SOUTHEAST OF SOUTHERN NEW ENGLAND. WINDS SHOULD
REMAIN BELOW 25 KT...EXCEPT FOR THE AFTERNOON AND EARLY EVENING
HOURS SURROUNDING CAPE COD AND THE ISLANDS...WHERE A FEW GUSTS COULD
APPROACH 25 KT MONDAY. OTHERWISE...SOME OVERNIGHT FOG AND STRATUS
MAY CAUSE OCCASIONAL REDUCTIONS IN VISIBILITY.
&&
.CLIMATE...
HERE ARE RECORD HIGHS FOR SOUTHERN NEW ENGLANDS OFFICIAL CLIMATE
SITES FOR JULY 5TH THROUGH THE 10TH
BOS PVD ORH BDL
6TH 101/1911 102/2010 102/2010 98/1911
7TH 99/1953 97/1993* 100/2010 95/1908
8TH 99/1937 99/1981 97/1993 97/1936*
9TH 99/1981* 99/1981 99/1936* 96/1937
10TH 101/1880 100/1993 100/1936* 95/1936*
* AND PREVIOUS YEARS
ALSO...SINCE WE ARE LOOKING AT AN EXTENDED PERIOD OF TEMPERATURES
ABOVE 90 DEGREES...HERE ARE THE LONGEST HEAT WAVES IN THE HISTORY
OF OUR 4 CLIMATE SITES.
HARTFORD/BRADLEY
JULY 24-AUGUST 2, 1995 - 10 DAYS
AUGUST 11-19, 2002 - 9 DAYS
AUGUST 27-SEPTEMBER 4, 1973 - 9 DAYS
JULY 27-AUGUST 3, 2006 - 8 DAYS
JULY 29-AUGUST 5, 2002 - 8 DAYS
JULY 16-23, 1991 - 8 DAYS
JULY 24-31, 1970 - 8 DAYS
AUGUST 28-SEPTEMBER 4, 1953 - 8 DAYS
AUGUST 10-17, 1944 - 8 DAYS
WORCESTER/AIRPORT
AUGUST 10-17, 1944 - 8 DAYS
JULY 4-11, 1912 - 8 DAYS
JUNE 26-JULY 3, 1901 - 8 DAYS
AUGUST 10-15, 1988 - 6 DAYS
JULY 25-29, 1963 - 5 DAYS
BOSTON/LOGAN AIRPORT
JULY 3-11, 1912 - 9 DAYS
AUGUST 11-18, 2002 - 8 DAYS
JULY 19-26, 1994 - 8 DAYS
AUGUST 10-17, 1944 - 8 DAYS
JUNE 28-JULY 5, 1872 - 8 DAYS
PROVIDENCE/T.F. GREEN
JULY 12-20, 1952 - 9 DAYS
JULY 28-AUGUST 3, 2006 - 7 DAYS
AUGUST 13-19, 2002 - 7 DAYS
JULY 15-21, 1977 - 7 DAYS
AUGUST 11-17, 1944 - 7 DAYS
JULY 7-13, 1944 - 7 DAYS
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK/SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
CLIMATE...
AREA FORECAST DISCUSSION
NWS ALBANY NY
1045 AM EDT FRI JUL 5 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL BE JUST EAST OF THE MID ATLANTIC
REGION THE NEXT SEVERAL DAYS. THIS HIGH WILL KEEP HOT AND HUMID
WEATHER OVER THE NORTHEAST FOR THE REMAINDER OF HOLIDAY WEEKEND.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
EACH DAY...MAINLY IN THE AFTERNOON AND EARLY EVENING HOURS. SOME
LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH ANY OF THUNDERSTORMS
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1045 AM EDT...NOT MUCH CHANGE IN THE FORECAST FOR THE REST
OF TODAY INTO THIS EVENING. REMOVED POPS FOR THE REST OF THE
MORNING...WITH A GRADUAL INCREASE IN SHOWERS AND THUNDERSTORMS
THIS AFTERNOON.
MAINLY ISOLATED TO SCATTERED COVERAGE STILL EXPECTED...WITH THE
BETTER CHANCE ACROSS WESTERN AREAS WHERE POSSIBLE LAKE BREEZE
INITIATION WILL OCCUR IN CENTRAL NY AND POSSIBLY TRACK EASTWARD
INTO THE MOHAWK VALLEY AND WESTERN ADIRONDACKS. HI RES MODELS SUCH
AS LOCAL WRF AND ESPECIALLY THE HRRR HAVE BEEN TOO AGGRESSIVE WITH
COVERAGE THE PAST FEW DAYS...SO NOT EXPECTING AS MUCH CONVECTION
AS WHAT IS BEING DEPICTED IN THESE MODELS. THE HRRR IMPLYING MORE
WIDESPREAD CONVECTION...BUT THIS LOOKS OVERDONE AT THIS TIME WITH
LIMITED FORCING.
SIMILAR SOUNDING PROFILE TO THE PAST FEW DAYS LOOKING AT 12Z KALB
SOUNDING. SBCAPE EXPECTED TO BUILD TO AROUND 2000 J/KG WITH
MODERATE MAGNITUDE OF DEEP LAYER SHEAR OF AROUND 30-35 KT.
HOWEVER...WARM TEMPS ALOFT OF AROUND -6C TO -7C AT 500 MB AND
POOR MID LEVEL LAPSE RATES OF LESS THAN 6.0 C/KM SHOULD LIMIT
SEVERITY OF STORMS. MAIN THREATS WILL BE HEAVY RAINFALL AND GUSTY
WINDS WITH ANY STORMS. FREEZING LEVELS ARE VERY HIGH AROUND 15 KFT
SO LARGE HAIL IS NOT EXPECTED TO OCCUR. PWATS REMAIN ABOVE NORMAL
WITH SURFACE DEWPOINTS IN THE MUGGY/OPPRESSIVE RANGE OF UPPER 60S
TO LOWER 70S.
CONTINUED HOT AND HUMID CONDITIONS...WITH HEAT INDICES GETTING TO
THE MID TO UPPER 90S IN MOST VALLEY LOCATIONS.
THE BERMUDA HIGH CONTINUES TO RIDGE WESTWARD AT ALL LEVELS OF THE
ATMOSPHERE THIS MORNING. THE WATER VAPOR LOOP SHOWS PLENTY OF DRY
AIR ON THE NW FLANK OF THE STRONG ANTICYCLONE OVER PORTIONS OF SRN
NY AND S-CNTRL NEW ENGLAND. A QUICK CHECK OF THE GLOBAL ENSEMBLES
INDICATES H500 HEIGHT ANOMALIES JUST OFF THE ERN SEABOARD OF 2 TO
3 STANDARD DEVIATIONS /STD DEVS/ ABOVE NORMAL FOR THE NEXT FEW
DAYS. THE AXIS OF DEEP MOISTURE TRANSPORT HAS SHIFTED WESTWARD
WITH THE FRONTAL BOUNDARY OVER THE GREAT LAKES REGION...OHIO
VALLEY...AND SOUTHWARD INTO THE SOUTHEAST. THE UPSTREAM TROUGH HAS
BECOME NEUTRAL TILTED OVER THE CNTRL PLAINS AND MO...AND APPEARS
IT WILL CLOSE OFF. IT IS GETTING SQUEEZED BETWEEN THE STRONG
THERMAL RIDGE OVER THE SOUTHWEST AND CA...AND THE STRONG CLOSED
BERMUDA HIGH ANTICYCLONE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
TONIGHT...THE EXPECTATION IS FOR ANY CONVECTION TO WEAKEN QUICKLY
IN THE EARLY EVENING...AND BE PRETTY MUCH GONE BY MIDNIGHT. THE
LOSS OF THE DAYTIME HEATING...AND WANING INSTABILITY SHOULD ALLOW
THE CONVECTIVE COVERAGE TO SHRIVEL QUICKLY. PARTLY CLOUDY/MOSTLY
CLEAR CONDITIONS WITH LIGHT WINDS WILL ALLOW PATCHY RADIATIONAL FOG
TO FORM AGAIN. LOWS WILL BE SIMILAR TO THE PAST FEW DAYS WITH
LOWER TO M60S OVER THE MTNS...AND WIDESPREAD U60S TO L70S OVER THE
HILLS/VALLEYS.
SATURDAY...A SFC TROUGH SLIDES EAST OF THE REGION WITH THE BERMUDA
HIGH SAGGING A BIT FURTHER TO THE SOUTH. THIS WILL ALLOW THE MID
LEVEL FLOW TO BECOME MORE ZONAL...AND PERHAPS A WEAK SHORT-WAVE
COUPLED WITH THE SFC TROUGH WILL BE A MORE DISTINCT TRIGGER OR
LIFTING MECHANISM FOR ISOLD-SCT CONVECTION. THE 0-6 KM EFFECTIVE
BULK SHEAR DOES STRENGTHEN CLOSER TO 40-45 KTS OVER THE REGION IN THE
AFTERNOON. SBCAPES OR MLCAPES INCREASE TO 1000-2000 J/KG. SPC DOES
NOT HAVE AN OUTLOOK...BUT A FEW STRONG TO SEVERE THUNDERSTORMS MAY
MATERIALIZE IF A CLEAR TRIGGER MECHANISM TAPS INTO THE UNSTABLE...HIGH
DEWPT/PWAT AIR. FOR NOW...WE WILL CONTINUE WITH SCT THUNDERSTORMS
IN THE AFTERNOON...AND MONITOR THIS PERIOD. WEAK COOLING DOES
OCCUR AT H850...BUT THE SFC WINDS VEERING TO THE SW AND W SHOULD
ALLOW LOCAL EFFECTS LIKE DOWNSLOPING/COMPRESSIONAL WARMING FOR MAX
TEMPS TO REACH THE U80S TO L90S FOR LOCATIONS 1000 FT OF ELEVATION
AND LOWER...AND U70S TO M80S OVER THE HIGHER TERRAIN AGAIN. SOME
SPOTTY 100 DEG HEAT INDICES MAY ALSO BE AROUND...BUT NOT
WIDESPREAD ENOUGH TO MENTION IN THE HWO FOR A POSSIBLE ADVISORY.
SATURDAY NIGHT...ANY SHOWERS OR THUNDERSTORM SHOULD DISSOLVE
QUICKLY AGAIN WITH THE LOSS OF THE DIURNAL HEATING. VARIABLE
CLOUDS...MUGGY CONDITIONS...AND PATCHY FOG WILL BE COMMON AGAIN
WITH LOWS IN THE 60S TO L70S...LIKE A BROKEN RECORD.
SUNDAY-SUNDAY NIGHT...SOME SMALL CHANGES WITH THE BERMUDA HIGH
SETTLING A LITTLE FURTHER SOUTHWARD...AND THE CLOSED LOW INCHING
CLOSER FROM THE OHIO VALLEY DURING THE AFTERNOON. SOME POP-UP
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AGAIN IN THE SULTRY AIR
MASS. THE BETTER SBCAPES OF 1500-2500 J/KG ACCORDING TO GFS ARE
OVER THE SRN ZONES...SOUTH OF THE CAPITAL REGION. H500 TEMPS STILL
AROUND -7C. PWATS CONTINUE IN THE 1.33-2.0" RANGE...SO SOME HEAVY
DOWNPOURS MAY OCCUR WITH ANY THUNDERSTORMS. IT COULD BE THE 4TH
DAY IN A ROW OF 90 DEG OR GREATER READINGS IN MANY OF THE HUDSON
RIVER VALLEY LOCATIONS...SUCH AS KALB AND KPOU. THE UPSTREAM CLOSED
LOW OVER THE OH VALLEY MAY MAKE A RUN AT PARTS OF THE REGION
SUNDAY NIGHT INTO MONDAY FOR A MORE SUSTAINED SHOWER AND
THUNDERSTORM THREAT.
NO RELIEF IS ON THE WAY PRIOR TO MONDAY WITH THE BALMY WEATHER
CONDITIONS CONTINUING...SO STAYING COOL WILL BE IMPORTANT...AS HEAT
INDICES WILL REMAIN WELL INTO THE 90S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MORE UNSETTLED WEATHER IS EXPECTED DURING THE LONG TERM PERIOD WITH
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS EACH DAY.
A BERMUDA HIGH SITUATED ALONG THE ATLANTIC SEABOARD MONDAY THROUGH
WEDNESDAY WILL CIRCULATE A SOUTHWESTERLY FLOW OF VERY WARM AND HUMID
AIR ACROSS OUR REGION WHILE A STATIONARY BOUNDARY WELL NORTH OF THE
CANADIAN BORDER MONDAY THROUGH TUESDAY FINALLY STARTS TO DROP
SOUTHEAST AS A COLD FRONT INTO THE SAINT LAWRENCE VALLEY ON
WEDNESDAY. THIS COLD FRONT THEN SWEEPS ACROSS OUR REGION WITH A
PRE-FRONTAL TROUGH AHEAD OF IT ON THURSDAY. THIS PATTERN WILL RESULT
IN VERY WARM AND HUMID CONDITIONS ACROSS OUR REGION WITH DIURNALLY
DRIVEN SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON AND
EVENING HOURS. EXPECT OVERNIGHT LOWS TO GENERALLY BE IN THE 60S TO
LOWER 70S EACH DAY WITH HIGHS IN THE UPPER 70S TO UPPER 80S...EXCEPT
SOME MID 70S ACROSS THE HIGHER TERRAIN OF THE WESTERN ADIRONDACKS ON
THURSDAY.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE EXPECTED AT THE TAF SITES THROUGH THE TAF PERIOD
ENDING AT 12Z SATURDAY. MAINLY SKC CONDITIONS ARE EXPECTED THIS
MORNING GIVING WAY TO SCT050 LATER THIS MORNING WITH BKN080
CONDITIONS THIS EVENING THROUGH TONIGHT.
WINDS WILL BE LIGHT AND VARIABLE BCMG SOUTHWEST AT 6-8 KTS LATER
THIS MORNING WITH GUSTS TO 18 KTS AT KALB AND KPSF THIS AFTERNOON
AND THEN LIGHT AND VARIABLE AGAIN THIS EVENING THROUGH TONIGHT.
OUTLOOK...
SAT-TUE...MAINLY VFR. ISOLD TO SCT AFTERNOON TO EARLY EVENING
SHRA/TSRA. POSSIBLE LATE NIGHT AND/OR EARLY MORNING FOG/LOW STRATUS
WITH MVFR/IFR POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES ARE EXPECTED THE NEXT SEVERAL DAYS.
THE RH TRENDS CONTINUE TO FAVOR EXCELLENT RECOVERIES EACH NIGHT WITH
85 TO 100 PERCENT READINGS AND WIDESPREAD DEW FORMATION. DAYTIME VALUES
THROUGH THE HOLIDAY WEEKEND WILL BE IN THE 40 TO 60 PERCENT RANGE.
THE BERMUDA HIGH WILL BE JUST EAST OF THE MID ATLANTIC
REGION THE NEXT SEVERAL DAYS. THIS HIGH WILL KEEP HOT AND HUMID
WEATHER OVER EASTERN NEW YORK AND WESTERN NEW ENGLAND. ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH
DAY...MAINLY IN THE AFTERNOON AND EARLY EVENING HOURS.
&&
.HYDROLOGY...
THE MOHAWK RIVER AT UTICA CONTINUES TO HAVE MINOR FLOODING. THE
RIVER AND CREEK FLOWS NEAR THE W-CNTRL MOHAWK RIVER ARE EXPECTED
TO GRADUALLY RECEDE INTO THE WEEKEND...UNLESS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS OCCUR OVER OR NEAR THE BASIN.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH THE HOLIDAY WEEKEND. A MOIST AND HUMID AIR MASS WILL ALLOW
ANY SHOWER OR THUNDERSTORM TO BE CAPABLE OF PRODUCING LOCALLY
HEAVY DOWNPOURS...AND A QUICK INCH OR MORE OF RAINFALL DUE TO THE
ANOMALOUS PRECIPITABLE WATER VALUES.
THERE WILL BE A CONTINUED THREAT FOR ISOLATED FLASH FLOODING...AS
WELL AS FLOODING OF POOR DRAINAGE AND LOW LYING AREAS. NO FLASH
FLOOD WATCHES ARE BEING ISSUED DUE TO THE EXPECTED ISOLATED NATURE
OF ANY FLOODING. IT IS ALSO DIFFICULT TO DETERMINE WHERE THE
HEAVIEST RAINFALL WILL OCCUR.
WHILE ADDITIONAL FLOODING IS NOT ANTICIPATED ON ANY MAIN STEM RIVER
POINTS...LOCALLY SHARP RISES ARE POSSIBLE DUE TO ANY CONVECTION THAT
MAY OCCUR OVER THE NEXT SEVERAL DAYS...ESPECIALLY FOR THOSE POINTS
THAT ARE MORE FLASHIER IN NATURE.
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...WASULA
NEAR TERM...JPV/WASULA
SHORT TERM...WASULA
LONG TERM...11
AVIATION...11
FIRE WEATHER...WASULA
HYDROLOGY...JPV/WASULA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
341 PM EDT Fri Jul 5 2013
.NEAR TERM [Through Tonight]...
Once again we have a large area of moderate to heavy rain with
embedded thunderstorms along the central to eastern Gulf coast,
although the primary axis of the activity is displaced a bit to the
west of the previous several days. The strongest RAP analyzed 850mb
moisture transport vectors are from the southeast from near buoy
42036, to near Cape San Blas, to southeast Alabama as of 18 UTC.
These are projected to focus in the western part of our area around
21 UTC before weakening into the evening. Therefore, we are
expecting rain to increase in our western zones over the next few
hours, with obvious concerns of additional rainfall exacerbating
flooding in Walton, Holmes, Bay, and Washington counties. More
scattered convection is expected to the east in a more unstable
environment. High-resolution models hint at a bit of a lull in the
evening again, with additional showers and storms redeveloping after
06 UTC in the western part of our area.
&&
.SHORT TERM [Saturday through Sunday Night]...
The upper level trof bringing the deep layer of SWrly flow of moist
Gulf air into the area will continue to lift NEward Saturday. This
will help weaken the pressure gradient aloft as well as further
decay the weak front to our west currently over Wrn MS. With the
anomalous pattern shifting, we`re adjusting closer to our normal
seabreeze pattern, especially over the Ern part of our forecast
area. Weak low pressure at lower levels in the Nrn GoMex will
continue to help with forcing for showers and thunderstorms,
bringing more rain to the area. As the low level forcing continues
to weaken, the intensity will not be as high as earlier this week.
Additionally, with 850-700mb flow, storms will continue to move
through more quickly (ex. today`s movement as opposed to Wed/Thurs
when storms would train over an area). CAM guidance is showing areas
of an additional 2-3" of rain is possible tomorrow over the Wrn half
of the forecast area, but if storms move quickly as expected the
rain will be distributed over a larger area. Flooding will still be
a concern as it takes time for basins to recede, especially after
the amount of rain we`ve seen. However, the threat of new additional
flooding is low.
The upper level pattern will continue to shift back to a less
amplified pattern Sunday, but weak low pressure over the Nrn Gulf
will continue the chances for potential rain in the areas that need
it the least. Similar to Saturday, the area will see still more rain
on Sunday, but not in the excessive amounts seen earlier this week,
so continued flooding will be an ongoing concern, but the threat of
new additional flooding will still be low.
&&
.LONG TERM [Monday through Friday]...
Weak ridging aloft and at the surface will begin to build Ewd as the
pattern deamplifies. Seasonal PoPs (around 40%) expected to take
over early next week. Around mid-week (Wed/Thurs), a weak UL trof
will swing through the Great Lakes region and a TUTT will be in the
Ern Gulf, which will create another disturbed pattern for our area.
Confidence is lower that far out in the run, but PoPs Thurs and Fri
around 40-50%. Temps will return to seasonal norms with highs in the
low 90s and lows in the low to mid 70s.
&&
.AVIATION...
[Through 18z Saturday] The main axis of tropical moisture has
shifted more to the west today but will still cause persistent rain
and low ceilings at ECP and DHN. ABY, VLD, and TLH will be at VFR;
however afternoon showers and thunderstorms will develop from east
to west along the east coast sea breeze. These storms could produce
gusty winds and reduced visibilities to 1SM.
&&
.MARINE...
Winds and waves are still slightly elevated over waters from
Ochlockonee River to Destin, so small craft should continue to
exercise caution through tomorrow morning. Winds and seas will
gradually fall over the weekend and should return to our
summertime norm by early next week.
&&
.FIRE WEATHER...
No fire weather concerns.
&&
.HYDROLOGY...
The flash flood threat continues across the western half of our
forecast area through Saturday evening, with the greatest threat
across the Florida Panhandle. Additional rainfall amounts of 2
to 3 inches are likely in the western half of watch area tomorrow,
but 3 to 5 inches are possible in the Panhandle.
On area rivers, the St. Marks near Newport has risen to moderate
flood stage, but appears to have crested. The Apalachicola River
at Blountstown is also forecast to rise to minor flood stage this
evening. The Aucilla River near Lamont is expected to reach minor
flood stage Saturday morning with a crest Sunday afternoon. The
Choctawhatchee River has crested just above minor flood stage at
Newton. At Caryville, the river should crest about a foot below
moderate flood stage Saturday night. Downstream at Bruce, the
river has risen to moderate flood stage and is forecast to
continue to rise to major flood stage by early next work week. The
Shoal River at Mossy Head has peaked at slightly above 14.1 ft
and has already fallen back below minor flood stage. As more rain
falls across the area, we will continue to monitor the area
rivers.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 86 72 90 71 / 50 60 30 40 20
Panama City 76 84 75 87 75 / 70 70 40 50 30
Dothan 71 83 71 88 71 / 70 70 40 60 30
Albany 72 87 72 90 72 / 60 50 30 50 30
Valdosta 72 88 70 90 71 / 40 50 30 30 20
Cross City 72 87 70 92 70 / 50 50 30 30 20
Apalachicola 78 85 75 86 75 / 70 70 40 40 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...FLASH FLOOD WATCH through Saturday evening for Calhoun-Central
Walton-Coastal Bay-Coastal Franklin-Coastal Gulf-Holmes-
Inland Bay-Inland Franklin-Inland Gulf-Inland Walton-
Jackson-Liberty-South Walton-Washington.
GA...None.
AL...FLASH FLOOD WATCH through Saturday evening for Coffee-Dale-
Geneva-Henry-Houston.
GM...None.
&&
$$
NEAR TERM...Lamers
SHORT TERM...Moore
LONG TERM...Moore
AVIATION...Walsh/Gould
MARINE...Moore
FIRE WEATHER...Moore
HYDROLOGY...Moore/Wool
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1208 PM EDT FRI JUL 5 2013
.UPDATE...SEA BREEZE IS STARTING TO PUSH THROUGH THE COASTAL
COUNTIES OF NE FLORIDA AND SE FLORIDA. PW VALUES OF 1.80 TO 1.90
INCHES EXIST. A WEAK DISTURBANCE IS NOTED ON SATELLITE IMAGERY
ALOFT NEAR PALM BAY THIS LATE MORNING WITH 15Z RUC SHOWS THE VERY
SIMILAR POSITION OVER WESTERN OSCEOLA. SHORT TERM MODELS SHOW
SPARSE TO ISOLATED COVERAGE OVER THE COASTAL COASTIES ALONG
RAPIDLY MOVING SEA-BREEZE WITH SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS OVER THE WESTERN CWA WITH BEST CHANCE OF HEAVY RAIN
FURTHER WEST ACROSS THE INTERIOR COUNTTIES. CURRENT POPS REFLECT
THIS STRATIFIED RAIN CHANCES FROM EAST TO WEST.
&&
.AVIATION...SEABREEZE ALONG THE COAST INITIALLY THIS MORNING IS
RAPIDLY PUSHING WESTWARD INTO THE INTERIOR THIS AFTERNOON.
ISOLATED SHOWERS AND THUNDERSTORMS ALONG THE COAST...WILL BECOME
MORE WIDESPREAD AS ONE GOES WEST OF A LINE FROM HILLIARD TO
CRESENT CITY. TEMPO IFR/MVFR CONDS CAN BE EXPECTED WITH RAIN
EFFICIENT TSTMS AND GUSTY OUTFLOW WINDS WITH ANY STRONGER STORMS.
OTHERWISE...VFR CONDITIONS FOR THE MOST PART. BRIEF GUSTY WINDS
WILL OCCUR FOR A 2 TO 3 HOUR WINDOW BEHIND THE SEABREEZE AT EACH
TERMINAL.
&&
.MARINE...SCEC HEADLINES MAY BE NEEDED THIS AFTERNOON IN THE 20 TO
60 NAUTICAL MILE RANGE DUE TO HEIGHTENED WINDS AND SEAS. OFFSHORE
CONDITIONS WILL GRADUALLY IMPROVE SUNDAY THROUGH EARLY NEXT WEEK
AS SEAS SUBSIDE. ONSHORE WINDS WILL CONTINUE BUT SPEEDS WILL
REMAIN BELOW 15 KNOTS.
RIP CURRENTS: MODERATE RISK OF RIP CURRENTS TODAY-SAT DUE TO
ELEVATED SURF CONDS. SURF NEAR 2-3 FT OBSERVED YESTERDAY AND
SIMILAR HEIGHTS EXPECTED TODAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 71 91 71 92 / 30 40 20 30
SSI 76 86 76 88 / 20 30 10 20
JAX 73 89 72 90 / 20 30 10 20
SGJ 75 87 76 88 / 20 30 10 20
GNV 71 91 71 91 / 30 40 30 30
OCF 72 92 72 92 / 40 40 30 30
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
CORDERO/ENYEDI/
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1004 AM CDT FRI JUL 5 2013
.DISCUSSION...
ISSUED 1005 AM CDT FRI JUL 5 2013
WILL UPDATE THE FORECAST TO REMOVE THE MORNING FOG...OTHERWISE
REST OF FORECAST IS THE SAME. ISOLATED SHOWERS AND THUNDERSTORMS TO
DEVELOP THIS AFTERNOON AS SKIES BECOME PARTLY SUNNY. HIGHS IN THE
LOWER TO MIDDLE 80S WITH SSE WINDS 5 TO 10 MPH.
578 DM 500 MB LOW OVER WEST CENTRAL MO TO TRACK SLOWLY INTO THE
MID MS VALLEY THIS WEEKEND AND CONTINUE DIRUNALLY DRIVEN ISOLATED
CONVECTION IN THE AFTERNOON/EARLY EVENING HOURS UNTIL SUNSET NEXT
FEW DAYS. TEMPS AND HUMIDITY LEVELS TO GRADUALLY INCREASE THROUGH
THE WEEK. HIGHS THIS AFTERNOON IN THE LOWER 80S EASTERN IL WHERE
MORE LOW CLOUDS PRESENT AND MID 80S WESTERN IL. A BIT HUMID TODAY
WITH DEWPOINTS IN THE 60S. SOME FOG COULD AGAIN DEVELOP AFTER
06Z/1 AM TONIGHT INTO EARLY SAT MORNING ESPECIALLY OVER EASTERN IL
IF THE CLOUDS CLEAR OUT ENOUGH DUE TO LIGHT WINDS AND MOIST
DEWPOINTS.
07
&&
.AVIATION...
ISSUED 627 AM CDT FRI JUL 5 2013
FAIRLY WIDESPREAD DENSE FOG...BUT SOMEWHAT SHALLOW...AFFECTING
AREAS FROM KBMI-KDEC EASTWARD THIS MORNING...WITH LOW STRATUS
AROUND A FEW HUNDRED FEET OFF THE GROUND. HAVE SEEN VISIBILITIES
LOWER TO AROUND 2 MILES WESTWARD TO KPIA/KSPI AS WELL. WORST OF
THE FOG SHOULD BE OVER THE NEXT HOUR...WITH QUICK IMPROVEMENT AS
THE STRONG JULY SUN KICKS IN. LATER THIS MORNING...DIURNAL CUMULUS
AROUND 4000 FEET SHOULD BEGIN TO DEVELOP TOWARD 15-16Z. RAP MODEL
LAYER HUMIDITY CONTINUES TO SUGGEST KCMI SEEING THE MOST
CLOUDS...WITH VFR CEILINGS AT TIMES.
WITH THE OVERALL PATTERN NOT CHANGING TOO MUCH...THINK WE WILL
SEE SOME LIGHT FOG DEVELOP AGAIN LATE TONIGHT. RIGHT NOW...HAVE
ONLY MENTIONED VISIBILITY BELOW 3/4SM AT KCMI...WITH MAINLY MVFR
VISIBILITIES ELSEWHERE.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 314 AM CDT FRI JUL 5 2013
ONLY SMALL ADJUSTMENTS IN THE FORECAST OVERALL THIS MORNING. VERY
LITTLE IN THE WAY OF LARGE SCALE CHANGES AS MODELS HOLD ON TO A
RATHER SLOW DEPARTURE OF THE UPPER TROF OVER THE MIDWEST.
INSTABILITY SHOWERS WILL REMAIN THE MAIN THREAT THROUGH THE
WEEKEND...UNTIL THAT TROF PULLS OUT TO THE NE. THEN THE MODELS
CONTINUE TO SPREAD SHOWERS ON THE EDGE OF THE MORE PROGRESSIVE
FLOW TO THE NORTH FOR THE FIRST PART OF THE WORK WEEK UNTIL A
FRONT DRAGS SOME SLIGHTLY COOLER AIR THROUGH THE REGION ON
WEDNESDAY. AT THE VERY LEAST...THIS FRONT MAY PROVIDE SOME DRYING
OUT IN THE EXTENDED FOR DAY 7. TEMPS WARMING MUCH CLOSER TO NORMAL
FOR JULY AS HOT AND MUGGY AIR PUSH INTO THE MIDWEST FROM A RATHER
WARM AND MUGGY GULF COAST OVER THE WEEKEND.
SHORT TERM...TODAY THROUGH SUNDAY...
GOING INTO THE WEEKEND...THE WEATHER PATTERN REMAINS MUCH THE
SAME. UNTIL THE UPPER WAVE MOVES OUT...WILL KEEP THE SLIGHT CHANCE
POPS IN THE AFTERNOON FOR POSSIBLE INSTABILITY SHOWERS. WITH THE
VERY SLOW MOVEMENT OF THE REMNANTS OF THE UPPER LOW...SHOWERS AND
TS HAVE BEEN CONFINED FOR THE LAST TWO AFTERNOONS TO NRN MO AND
SRN IA. AS A RESULT...EDGED THE POPS THIS AFTERNOON TO CHANCE FOR
EXTREME SW. THESE AFTERNOON SHOWERS REMAIN AN ISSUE THROUGH THE
WEEKEND...THOUGH LIKELY VERY SCT IN NATURE IF THE 4KM WRF IS ANY
INDICATION. OTHER ISSUE THROUGH THE WEEKEND IS THAT WITH THE
RATHER STAGNANT FLOW ALOFT...NOTHING IS REALLY PUSHING THE STALLED
BOUNDARY OVER INDIANA OUT OF THE WAY. BOUNDARY WOBBLES A BIT HERE
AND THERE...SLIGHTLY RISING THE CHANCES FOR SOME PRECIP IN EXTREME
EASTERN IL. WARM AND MUGGY AIR MOVING IN BRINGING TEMPS INTO THE
80S WITH NEAR 70 DEGREE DWPTS AND HEAT INDICES INTO THE UPPER 80S.
IN ADDITION...WILL HAVE TO WATCH AFTERNOON XOVER TEMPS AS THE
MORNINGS WILL MORE THAN LIKELY SATURATE AT SOME POINT AND CREATE A
FOG ISSUE FOR EARLY MORNING. COVERAGE AND CERTAINTY ARE STILL A
BIT WANTING...AND HAVE LEFT IT OUT OF THE GRIDS SO FAR.
LONG TERM...MONDAY THROUGH THURSDAY...
WAVE FINALLY PULLS OUT OF THE FA AND LEAVES MUCH OF THE SRN TWO
THIRDS OF THE COUNTRY WITHOUT A WHOLE LOT OF DYNAMICS ALOFT. MORE
PROGRESSIVE STREAM JUST TO THE NORTH...LEAVING MUCH OF NRN HALF OF
STATE ON THE EDGE OF THE FLOW AND MODELS CONSISTENT WITH RATHER
EXTENSIVE ACTIVITY MON/TUE. WITH PLENTY OF UNSTABLE AIR IN PLACE
FROM THE WEEKENDS OPEN GULF...ANY RIPPLE ALONG THAT FLOW LIKELY TO
BE ENOUGH TO HELP KICK OFF SHOWERS AND TS. ONCE IT STARTS...THE
MESOSCALE STORM FEATURES AND BOUNDARIES WILL CONTINUE TO PROVIDE A
RAINY/STORMY COUPLE OF DAYS. AT LEAST UNTIL A COLD FRONT FINALLY
SWEEPS THROUGH THE REGION ON WEDNESDAY. THOUGH THE TEMPERATURES ON
THE OTHER SIDE OF IT MAY NOT BE SIGNIFICANTLY COOLER...THE MODELS
DO DRY OUT THE REGION A BIT...PROVIDING A BREAK FROM THE POPS FOR
THURSDAY.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
627 AM CDT FRI JUL 5 2013
.DISCUSSION...
ISSUED 314 AM CDT FRI JUL 5 2013
ONLY SMALL ADJUSTMENTS IN THE FORECAST OVERALL THIS MORNING. VERY
LITTLE IN THE WAY OF LARGE SCALE CHANGES AS MODELS HOLD ON TO A
RATHER SLOW DEPARTURE OF THE UPPER TROF OVER THE MIDWEST.
INSTABILITY SHOWERS WILL REMAIN THE MAIN THREAT THROUGH THE
WEEKEND...UNTIL THAT TROF PULLS OUT TO THE NE. THEN THE MODELS
CONTINUE TO SPREAD SHOWERS ON THE EDGE OF THE MORE PROGRESSIVE
FLOW TO THE NORTH FOR THE FIRST PART OF THE WORK WEEK UNTIL A
FRONT DRAGS SOME SLIGHTLY COOLER AIR THROUGH THE REGION ON
WEDNESDAY. AT THE VERY LEAST...THIS FRONT MAY PROVIDE SOME DRYING
OUT IN THE EXTENDED FOR DAY 7. TEMPS WARMING MUCH CLOSER TO NORMAL
FOR JULY AS HOT AND MUGGY AIR PUSH INTO THE MIDWEST FROM A RATHER
WARM AND MUGGY GULF COAST OVER THE WEEKEND.
SHORT TERM...TODAY THROUGH SUNDAY...
GOING INTO THE WEEKEND...THE WEATHER PATTERN REMAINS MUCH THE
SAME. UNTIL THE UPPER WAVE MOVES OUT...WILL KEEP THE SLIGHT CHANCE
POPS IN THE AFTERNOON FOR POSSIBLE INSTABILITY SHOWERS. WITH THE
VERY SLOW MOVEMENT OF THE REMNANTS OF THE UPPER LOW...SHOWERS AND
TS HAVE BEEN CONFINED FOR THE LAST TWO AFTERNOONS TO NRN MO AND
SRN IA. AS A RESULT...EDGED THE POPS THIS AFTERNOON TO CHANCE FOR
EXTREME SW. THESE AFTERNOON SHOWERS REMAIN AN ISSUE THROUGH THE
WEEKEND...THOUGH LIKELY VERY SCT IN NATURE IF THE 4KM WRF IS ANY
INDICATION. OTHER ISSUE THROUGH THE WEEKEND IS THAT WITH THE
RATHER STAGNANT FLOW ALOFT...NOTHING IS REALLY PUSHING THE STALLED
BOUNDARY OVER INDIANA OUT OF THE WAY. BOUNDARY WOBBLES A BIT HERE
AND THERE...SLIGHTLY RISING THE CHANCES FOR SOME PRECIP IN EXTREME
EASTERN IL. WARM AND MUGGY AIR MOVING IN BRINGING TEMPS INTO THE
80S WITH NEAR 70 DEGREE DWPTS AND HEAT INDICES INTO THE UPPER 80S.
IN ADDITION...WILL HAVE TO WATCH AFTERNOON XOVER TEMPS AS THE
MORNINGS WILL MORE THAN LIKELY SATURATE AT SOME POINT AND CREATE A
FOG ISSUE FOR EARLY MORNING. COVERAGE AND CERTAINTY ARE STILL A
BIT WANTING...AND HAVE LEFT IT OUT OF THE GRIDS SO FAR.
LONG TERM...MONDAY THROUGH THURSDAY...
WAVE FINALLY PULLS OUT OF THE FA AND LEAVES MUCH OF THE SRN TWO
THIRDS OF THE COUNTRY WITHOUT A WHOLE LOT OF DYNAMICS ALOFT. MORE
PROGRESSIVE STREAM JUST TO THE NORTH...LEAVING MUCH OF NRN HALF OF
STATE ON THE EDGE OF THE FLOW AND MODELS CONSISTENT WITH RATHER
EXTENSIVE ACTIVITY MON/TUE. WITH PLENTY OF UNSTABLE AIR IN PLACE
FROM THE WEEKENDS OPEN GULF...ANY RIPPLE ALONG THAT FLOW LIKELY TO
BE ENOUGH TO HELP KICK OFF SHOWERS AND TS. ONCE IT STARTS...THE
MESOSCALE STORM FEATURES AND BOUNDARIES WILL CONTINUE TO PROVIDE A
RAINY/STORMY COUPLE OF DAYS. AT LEAST UNTIL A COLD FRONT FINALLY
SWEEPS THROUGH THE REGION ON WEDNESDAY. THOUGH THE TEMPERATURES ON
THE OTHER SIDE OF IT MAY NOT BE SIGNIFICANTLY COOLER...THE MODELS
DO DRY OUT THE REGION A BIT...PROVIDING A BREAK FROM THE POPS FOR
THURSDAY.
HJS
&&
.AVIATION...
ISSUED 627 AM CDT FRI JUL 5 2013
FAIRLY WIDESPREAD DENSE FOG...BUT SOMEWHAT SHALLOW...AFFECTING
AREAS FROM KBMI-KDEC EASTWARD THIS MORNING...WITH LOW STRATUS
AROUND A FEW HUNDRED FEET OFF THE GROUND. HAVE SEEN VISIBILITIES
LOWER TO AROUND 2 MILES WESTWARD TO KPIA/KSPI AS WELL. WORST OF
THE FOG SHOULD BE OVER THE NEXT HOUR...WITH QUICK IMPROVEMENT AS
THE STRONG JULY SUN KICKS IN. LATER THIS MORNING...DIURNAL CUMULUS
AROUND 4000 FEET SHOULD BEGIN TO DEVELOP TOWARD 15-16Z. RAP MODEL
LAYER HUMIDITY CONTINUES TO SUGGEST KCMI SEEING THE MOST
CLOUDS...WITH VFR CEILINGS AT TIMES.
WITH THE OVERALL PATTERN NOT CHANGING TOO MUCH...THINK WE WILL
SEE SOME LIGHT FOG DEVELOP AGAIN LATE TONIGHT. RIGHT NOW...HAVE
ONLY MENTIONED VISIBILITY BELOW 3/4SM AT KCMI...WITH MAINLY MVFR
VISIBILITIES ELSEWHERE.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
251 PM CDT FRI JUL 5 2013
...UPDATED FOR LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 200 PM CDT FRI JUL 5 2013
AGAIN FOR THIS EVENING, WINDS WILL START OUT BREEZY FROM THE SOUTH
TO SOUTHWEST AT 18G28KT AS HAPPENED THURSDAY EVENING, THEN WILL
BECOME SOUTH TO SOUTHEAST AT 13 TO 15 KNOTS AFTER 00Z. THERE HAVE
BEEN A FEW ALTOCUMULUS CLOUDS IN THE 10-12 THOUSAND FOOT RANGE
AND FLOWING CIRRUS IN THE 25 THOUSAND FOOT RANGE THIS AFTERNOON.
WITH THE COMBINATION OF THESE FEATURES, I THINK THE TEMPERATURES
WILL FALL SLOWLY OVERNIGHT TO MINIMUMS IN THE MID 60S TO THE LOWER
70S. THE SHORT RANGE MODELS OF THE RUC AND NAM BOTH SUPPORT LOWS
IN THIS RANGE. WINDS WILL HELP SLIGHTLY IN KEEPING THE
TEMPERATURES ELEVATED.
ON SATURDAY, IT LOOKS HOTTER AS THE NAM AND ECMWF MODELS BRING IN
THE +32C ISOTHERM AT 850MB AND +15C AIR AT 700MB INTO OUR WESTERN
ZONES NEAR THE COLORADO BORDER. THE SOUTHWESTERLY FLOW WILL BRING
WARM AIR FROM THE SOUTH AND SOUTHWEST. ADDITIONALLY, A DOWNSLOPE
AFFECT FROM THE NORTHWESTERLY FLOW AT MID AND HIGHER LAYERS WILL
KICK IN. EVEN THROUGH THERE WILL BE SOME CIRRUS CEILINGS OVERHEAD,
MUCH OF THE CIRRUS WILL BE THIN AND NOT NEGATIVELY EFFECT SURFACE
WARMING. HIGHS AROUND 100F WILL RETURN TO SOUTHWESTERN KANSAS ON
SATURDAY, ESPECIALLY FROM LIBERAL TO GARDEN CITY TO DODGE CITY TO
HAYS. OTHER AREAS NEAR THE COLORADO BORDER WILL STILL TOP OUT IN
THE UPPER 90S.
THERE IS A SURFACE TROUGH THAT WILL ENCROACH ON THE WESTERN BORDER
NEAR COLORADO LATE IN THE DAY. A FEW THUNDERSTORMS MAY FORM ALONG
AND NEAR THE COLORADO BORDER, AHEAD OF THE TROUGH LATE SATURDAY.
ALSO THERE IS A WEAK UPPER WAVE COMING OVER NORTHWESTERN KANSAS BY
00Z SUNDAY, WHICH WILL ADD UPPER LEVEL SUPPORT FOR A FEW STORMS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 251 PM CDT FRI JUL 5 2013
SATURDAY NIGHT INTO SUNDAY WILL SEE THE UPPER RIDGE EXPAND OUT OF
THE DESERT SOUTHWEST BUT ALSO TURN RELATIVELY FLAT AS IT ELONGATES
OVER THE SOUTHERN HALF OF THE COUNTRY. THIS WILL LEAVE WESTERN AND
CENTRAL KANSAS AT THE TAIL END OF THE WESTERLIES WITH JUST ENOUGH
CROSS MOUNTAIN FLOW TO DEEPEN THE LEE TROUGH ALONG THE
KANSAS...COLORADO BORDER. IN ADDITION...A MODEST 60 KNOT UPPER JET
STREAK OVER THE DAKOTAS WILL AID IN PUSHING A WEAK COLD FRONT
SOUTHWARD OVER THE NORTHERN PLAINS BUT THEN STALLING NEAR THE
KANSAS...NEBRASKA BORDER BY EARLY SUNDAY. CONDITIONS WILL WARM
QUICKLY UNDER THIS REGIME AS 700 HPA TEMPERATURES ABOVE 14 C
ACROSS THE ROCKIES AND DESERT SOUTHWEST...SPREAD EASTWARD INTO THE
ADJACENT HIGH PLAINS WITH A RESULTANT STRONG CAPPING ELEVATED
MIXED LAYER. NONETHELESS...BOTH SATURDAY EVENING AND AGAIN SUNDAY
EVENING WILL SEE HIGHER BASED CONVECTION DEVELOPING ALONG THE LEE
TROUGH OR FARTHER WEST OVER ELEVATED TERRAIN REGIONS OF
COLORADO...MOVING VERY SLOWLY EAST INTO FAR WESTERN KANSAS.
COVERAGE WILL BE ISOLATED OR AT BEST SCATTERED AT TIMES WITH LOW
PROBABILITY PRECIPITATION CHANCES EXISTING MAINLY WEST OF HIGHWAY
283 BOTH EVENINGS. SEVERE THREAT WITH THIS CONVECTION WILL BE
MINIMAL AS SHEAR PROFILES ARE WEAK AND DO NOT SUPPORT ROTATING
UPDRAFTS BUT INVERTED V PROFILES COULD SUPPORT SOME ISOLATED
DAMAGING WIND POTENTIAL. TEMPERATURE WISE...STRONG INSOLATION WILL
PERMIT MIXING UP 700 HPA WITH RESULTANT AFTERNOON MAXIMUM
TEMPERATURES AROUND 100 FOR SUNDAY.
MONDAY INTO MONDAY NIGHT IS LOOKING LIKE A NEAR COPY OF SUNDAY AS
THE UPPER PATTERN REMAINS DOMINATED BY THE FLAT BUT ELONGATED
RIDGE OVER THE SOUTHERN HALF OF THE COUNTRY. THIS WILL LEAVE THE
LEE TROUGH SITTING ALONG THE COLORADO BORDER WHILE A WEAK COLD
FRONT REMAINS STALLED NEAR THE NEBRASKA BORDER WITH KANSAS. WITH
700 HPA TEMPERATURES AROUND 14C AND MIXING UP TO THIS LEVEL
LIKELY...HIGHS AROUND 100 APPEAR POSSIBLE YET AGAIN. IN
ADDITION...SIMILAR TO BOTH SATURDAY AND SUNDAY EVENING ISOLATED
THUNDERSTORMS WILL BE POSSIBLE FOR LOCATIONS MAINLY WEST OF A
LIBERAL TO WAKEENEY LINE AS STORMS FORMING OVER HIGHER TERRAIN IN
COLORADO MOVE SLOWLY EAST.
TUESDAY WILL SEE THE UPPER RIDGE AXIS BOTH AMPLIFY AND RETROGRADE
FAR ENOUGH WEST TO ALLOW A WEAK COLD FRONT TO SLIP INTO NORTHERN
OKLAHOMA DURING THE EVENING TO OVERNIGHT HOURS. INITIALLY THIS
WILL RESULT IN ANOTHER 100+ DEGREE DAY OVER SOUTHWEST INTO CENTRAL
KANSAS AS STRONG SOLAR INSOLATION ALONG WITH PREFRONTAL WARMING
ALLOW TEMPERATURES TO SORE INTO THE TRIPLE DIGITS.
HOWEVER...ARRIVAL OF THIS FRONT WILL ALSO BRING AN INCREASED
CHANCE FOR THUNDERSTORMS TUESDAY EVENING TO OVERNIGHT. ATTENTION
THEN TURNS TOWARD WEDNESDAY AND THURSDAY AS SLIGHTLY COOLER
CONDITIONS EXIST BEHIND THE FRONT BOTH DAYS ALONG WITH A DECENT
SETUP FOR A NOCTURNAL MCS MOVING OUT OF COLORADO AND NORTHERN NEW
MEXICO. NONETHELESS...THE RIDGE THEN BUILDS BACK EAST INTO THE
PLAINS BY FRIDAY WITH THE FRONT MOVING QUICKLY NORTH OF KANSAS.
THIS WILL PERMIT TEMPERATURES TO RISE BACK INTO THE TRIPLE DIGITS FOR
HIGHS WITH GENERALLY DRY CONDITIONS EXISTING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1214 PM CDT FRI JUL 5 2013
VFR CONDITIONS WILL CONTINUE THROUGH 18Z SATURDAY. A FEW
ALTOCUMULUS CLOUDS IN THE 100-120 THOUSAND FOOT RANGE, AND PASSING
CIRRUS CLOUDS IN THE 200-250 THOUSAND FOOT RANGE WILL BE AROUND
TONIGHT. THE CIRRUS CLOUDS MAY GO BROKEN AFTER 14Z SATURDAY. THE
BREEZY SOUTH WINDS THIS AFTERNOON IN THE 15G25KT RANGE WILL
SUBSIDE TO SOUTHEAST AT 13 TO 25 KNOTS AFTER 00Z. WINDS ON
SATURDAY WILL BE STRONG FROM THE SOUTH, AND GENERALLY IN THE
20G30KT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 100 70 100 / 10 10 10 10
GCK 69 100 69 99 / 10 10 20 10
EHA 68 98 70 97 / 10 20 20 20
LBL 66 100 70 100 / 10 10 10 10
HYS 69 100 71 102 / 10 10 10 10
P28 69 100 73 100 / 10 10 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...AJOHNSON
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
202 PM CDT FRI JUL 5 2013
...UPDATED FOR THE SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 200 PM CDT FRI JUL 5 2013
AGAIN FOR THIS EVENING, WINDS WILL START OUT BREEZY FROM THE SOUTH
TO SOUTHWEST AT 18G28KT AS HAPPENED THURSDAY EVENING, THEN WILL
BECOME SOUTH TO SOUTHEAST AT 13 TO 15 KNOTS AFTER 00Z. THERE HAVE
BEEN A FEW ALTOCUMULUS CLOUDS IN THE 100-120 THOUSAND FOOT RANGE AND
FLOWING CIRRUS IN THE 250 THOUSAND FOOT RANGE THIS AFTERNOON. WITH
THE COMBINATION OF THESE FEATURES, I THINK THE TEMPERATURES WILL
FALL SLOWLY OVERNIGHT TO MINIMUMS IN THE MID 60S TO THE LOWER 70S.
THE SHORT RANGE MODELS OF THE RUC AND NAM BOTH SUPPORT LOWS IN THIS
RANGE. WINDS WILL HELP SLIGHTLY IN KEEPING THE TEMPERATURES
ELEVATED.
ON SATURDAY, IT LOOKS HOTTER AS THE NAM AND ECMWF MODELS BRING IN
THE +32C ISOTHERM AT 850MB AND +15C AIR AT 700MB INTO OUR WESTERN
ZONES NEAR THE COLORADO BORDER. THE SOUTHWESTERLY FLOW WILL BRING
WARM AIR FROM THE SOUTH AND SOUTHWEST. ADDITIONALLY, A DOWNSLOPE
AFFECT FROM THE NORTHWESTERLY FLOW AT MID AND HIGHER LAYERS WILL
KICK IN. EVEN THROUGH THERE WILL BE SOME CIRRUS CEILINGS OVERHEAD,
MUCH OF THE CIRRUS WILL BE THIN AND NOT NEGATIVELY EFFECT SURFACE
WARMING. HIGHS AROUND 100F WILL RETURN TO SOUTHWESTERN KANSAS ON
SATURDAY, ESPECIALLY FROM LIBERAL TO GARDEN CITY TO DODGE CITY TO
HAYS. OTHER AREAS NEAR THE COLORADO BORDER WILL STILL TOP OUT IN
THE UPPER 90S.
THERE IS A SURFACE TROUGH THAT WILL ENCROACH ON THE WESTERN BORDER
NEAR COLORADO LATE IN THE DAY. A FEW THUNDERSTORMS MAY FORM ALONG
AND NEAR THE COLORADO BORDER, AHEAD OF THE TROUGH LATE SATURDAY.
ALSO THERE IS A WEAK UPPER WAVE COMING OVER NORTHWESTERN KANSAS BY
00Z SUNDAY, WHICH WILL ADD UPPER LEVEL SUPPORT FOR A FEW STORMS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 AM CDT FRI JUL 5 2013
A RATHER TYPICAL SUMMER PATTERN WILL PREVAIL ACROSS THE SOUTHWEST
KANSAS REGION FROM SATURDAY THROUGH MID NEXT WEEK. THE 500MB HIGH
OVER THE WEEKEND WILL BE CENTERED ACROSS THE ARIZONA-NEW MEXICO
BORDER REGION WITH A WEAK JET CORE MOVING ACROSS THE NORTHERN
ROCKIES INTO THE DAKOTAS. THE RIDGE WILL BECOME FAIRLY FLAT GOING
INTO EARLY NEXT WEEK FROM ARIZONA/NEW MEXICO INTO OKLAHOMA AS ZONAL
FLOW PREVAILS ACROSS THE NORTHERN CONUS. THIS PATTERN WILL LEAD TO A
SUSTAINED LEE TROUGH FEATURE WITH A WEAK FRONTAL PUSH AS WEAK
SHORTWAVE TROUGHS MOVE ACROSS THE NORTHERN PLAINS WITHIN THE ZONAL
JET STREAM. NONE OF THESE FRONTAL SURGES ARE EXPECTED TO REACH
SOUTHERN KANSAS GIVEN THE STRENGTH OF THE SUBTROPICAL RIDGING FROM
THE DESERT SOUTHWEST REGION INTO THE SOUTHERN PLAINS. FROM SATURDAY
THROUGH TUESDAY...THIS PATTERN WILL YIELD AFTERNOON TEMPERATURES IN
THE UPPER 90S TO AROUND 100 DEGREES WITH OVERNIGHT LOWS WARM IN THE
LOWER TO PERHAPS MID 70S. DIURNAL CONVECTION WILL BE POSSIBLE EACH
DAY ALONG THE LEE TROUGH CONVERGENCE AXIS (AND MORE LIKELY OVER
TERRAIN-FAVORED REGIONS OF COLORADO)...BUT THE OVERALL WEAK
MID-UPPER TROPOSPHERIC FLOW WILL PREVENT AN EASTWARD PUSH OF
CONVECTION FAR INTO WESTERN KANSAS. AS A RESULT...SLIGHT CHANCE
POPS WILL BE CONFINED ONLY TO FAR WEST-CENTRAL AND SOUTHWEST KANSAS.
A COLD FRONT PUSH LATE TUESDAY AND WEDNESDAY WOULD LEAD TO AN
INCREASED CHANCE FOR THUNDERSTORMS OVER A LARGER PORTION OF
SOUTHWEST KANSAS AS SUGGESTED BY THE LATEST ECMWF MODEL (AS A
STRONGER SHORTWAVE TROUGH/UPPER LOW DEVELOPS ACROSS THE NORTHERN
DAKOTAS ADJACENT CANADA INTO THE UPPER MIDWEST REGION). SHOULD THE
FRONT PENETRATE KANSAS MID-WEEK...AFTERNOON TEMPERATURES WILL BE
COOLER WITH HIGHS IN THE LOWER TO MID 90S INSTEAD OF THE LOW 100S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1214 PM CDT FRI JUL 5 2013
VFR CONDITIONS WILL CONTINUE THROUGH 18Z SATURDAY. A FEW
ALTOCUMULUS CLOUDS IN THE 100-120 THOUSAND FOOT RANGE, AND PASSING
CIRRUS CLOUDS IN THE 200-250 THOUSAND FOOT RANGE WILL BE AROUND
TONIGHT. THE CIRRUS CLOUDS MAY GO BROKEN AFTER 14Z SATURDAY. THE
BREEZY SOUTH WINDS THIS AFTERNOON IN THE 15G25KT RANGE WILL
SUBSIDE TO SOUTHEAST AT 13 TO 25 KNOTS AFTER 00Z. WINDS ON
SATURDAY WILL BE STRONG FROM THE SOUTH, AND GENERALLY IN THE
20G30KT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 100 70 100 / 10 10 10 10
GCK 69 100 69 99 / 10 10 20 10
EHA 68 98 70 97 / 10 20 20 20
LBL 66 100 70 100 / 10 10 10 10
HYS 69 100 71 102 / 10 10 10 10
P28 69 100 73 100 / 10 10 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURKE
LONG TERM...UMSCHEID
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1228 PM CDT FRI JUL 5 2013
...UPDATED FOR THE 18Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1000 PM CDT THU JUL 4 2013
THE 05.00Z 250 HPA RAOB MAP SHOWED A RATHER STAGNANT UPPER AIR FLOW
PATTERN AS COMPARED TO THE 04.00Z RAOBS. BASICALLY, ANTICYCLONIC FLOW
PREVAILED ACROSS THE WESTERN UNITED STATES AND MERIDIONAL FLOW CONTINUED
FARTHER DOWNSTREAM. MAGNITUDES WERE 70 KT (@72768) ON THE TOP OF THE
RIDGE AND THE STRONGEST SOUTHERLY FLOW DOWNSTREAM WAS AROUND 115 KT
(@72645). @ 500 HPA, THE CENTER OF A 592 DM ANTICYCLONE WAS NEAR 72388.
FAIRLY WARM MID LEVEL TEMPERATURES OF -5 DEG C WERE ASSOCIATED WITH
SAID PRESSURE PERTURBATION. DOWNSTREAM, A BROAD TROF EXTENDED ROUGHLY
FROM 72440 TO 72645. TEMPERATURES WERE IN THE -13 TO -14 DEG C RANGE.
AT 700 HPA, 2 DEGREES C OF WARMING WERE NOTED AT 72451 IN COMPARING
04.00Z AND 05.00Z RAOBS. SAME ORDER OF MAGNITUDE OF WARMING WAS NOTED
AT 850 HPA FOR THE SAME UPPER AIR SITE. AT THE SFC, A LEE SURFACE TROF
WAS ANALYZED ACROSS SE COLORADO. A COLD FRONT EXTENDED FROM EASTERN NORTH
DAKOTA SOUTHWARD TO THE NEBRASKA PANHANDLE. TROPICAL DEPRESSION DALILA WAS
LOCATED NEAR 17.3N 111.0W @ 05.03Z AND TROPICAL STORM ERICK WAS LOCATED
NEAR 14.9N 100.0W @ 05.03Z
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 100 AM CDT FRI JUL 5 2013
THIS MORNING:
THE FORECAST THIS MORNING IS RATHER UNCOMPLICATED AND STRAIGHT FORWARD.
THE HRRR AND TO A LESSER EXTENT THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS SOME QPF ACROSS THE REGION THIS MORNING. SATELLITE WATER VAPOR
IMAGERY SHOWS A SMALL PERTURBATION MOVING ACROSS THE REGION THIS MORNING
IN THE NORTHERLY FLOW ALOFT. IN ADDITION, KDDC WSR- 88D VAD PROFILE
SHOWS A STRENGTHENING 850 HPA LOW LEVEL JET THROUGH 05Z. FEEL THAT THE
HRRR IS A BIT AGGRESSIVE WITH QPF. THE NAM IS MORE CONSERVATIVE AND
KEEPS ANY PRECIPITATION THIS MORNING CLOSER THE TROF MENTIONED IN THE
SYNOPSIS. AS A RESULT, WILL KEEP PROBABILITY PRECIPITATION PERCENTAGE
POINTS AT OR BELOW 14 PERCENT DUE TO DISAGREEMENT IN THE MESOSCALE MODELS.
OTHER MESOSCALE MODELS SUCH AS THE WRF-ARW DO NOT SHOW ANYTHING EXCITING
DURING THIS PERIOD.
TODAY:
NEAR NEUTRAL 500 HPA GEOPOTENTIAL HEIGHT TENDENCIES ARE EXPECTED TODAY.
AT THE SFC, A LEE TROUGH WILL CONTINUE ACROSS EASTERN COLORADO. THE
NET RESULT IS PRETTY MUCH A CARBON COPY OF YESTERDAYS SENSIBLE WEATHER
FOR TODAY... ERGO A FEW CLOUDS AND BREEZY SOUTHERLY WINDS. MAXIMUM TEMPERATURES
WILL BE HIGHER THAN COMPARED TO YESTERDAY AND IN THE MID 90S AS THE
850 HPA WARM PLUME ADVECTS FARTHER EAST. EVEN THOUGH IT WILL BE VERY
WARM TO HOT AND BREEZY, CRITICAL FIRE WEATHER CONDITIONS ARE NOT EXPECTED
TODAY AS DOWNSLOPE SOUTHWESTERLY WINDS ARE NOT EXPECTED WHICH IS THE
MOST IDEAL FOR RED FLAG WARNING CONDITIONS.
TONIGHT:
BY DUSK, WINDS SHOULD ABATE AS THE BOUNDARY LAYER DECOUPLES WITH SOUTHERLY
WINDS OF MAGNITUDES 10-18 MPH IS EXPECTED THROUGH LATE EVENING. THE
OPERATIONAL 05.00Z NAM RUN SHOWS THE POSSIBILITY OF CONVECTION ACROSS
WESTERN KANSAS TONIGHT. THE NESTED 05.00Z 4 KM NAM KEEPS CONVECTION
ACROSS EASTERN COLORADO. GIVEN THE WEAK FLOW ALOFT AND EXPECTED CONVERGENCE
FARTHER WEST, WILL KEEP PRECIPITATION PROBABILITY PERCENTAGE POINTS
AT OR BELOW 14 PERCENT. EVEN TAKING THE OPERATIONAL RUN OF THE NAM AT
FACE VALUE, AN INSPECTION OF FORECAST SKEW T/LOG-P`S SHOW WEAK INSTABILITY.
OTHERWISE, MINIMUMS HEADING INTO SATURDAY MORNING WILL BE IN THE UPPER
60S DEG F.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 AM CDT FRI JUL 5 2013
A RATHER TYPICAL SUMMER PATTERN WILL PREVAIL ACROSS THE SOUTHWEST
KANSAS REGION FROM SATURDAY THROUGH MID NEXT WEEK. THE 500MB HIGH
OVER THE WEEKEND WILL BE CENTERED ACROSS THE ARIZONA-NEW MEXICO
BORDER REGION WITH A WEAK JET CORE MOVING ACROSS THE NORTHERN
ROCKIES INTO THE DAKOTAS. THE RIDGE WILL BECOME FAIRLY FLAT GOING
INTO EARLY NEXT WEEK FROM ARIZONA/NEW MEXICO INTO OKLAHOMA AS ZONAL
FLOW PREVAILS ACROSS THE NORTHERN CONUS. THIS PATTERN WILL LEAD TO A
SUSTAINED LEE TROUGH FEATURE WITH A WEAK FRONTAL PUSH AS WEAK
SHORTWAVE TROUGHS MOVE ACROSS THE NORTHERN PLAINS WITHIN THE ZONAL
JET STREAM. NONE OF THESE FRONTAL SURGES ARE EXPECTED TO REACH
SOUTHERN KANSAS GIVEN THE STRENGTH OF THE SUBTROPICAL RIDGING FROM
THE DESERT SOUTHWEST REGION INTO THE SOUTHERN PLAINS. FROM SATURDAY
THROUGH TUESDAY...THIS PATTERN WILL YIELD AFTERNOON TEMPERATURES IN
THE UPPER 90S TO AROUND 100 DEGREES WITH OVERNIGHT LOWS WARM IN THE
LOWER TO PERHAPS MID 70S. DIURNAL CONVECTION WILL BE POSSIBLE EACH
DAY ALONG THE LEE TROUGH CONVERGENCE AXIS (AND MORE LIKELY OVER
TERRAIN-FAVORED REGIONS OF COLORADO)...BUT THE OVERALL WEAK
MID-UPPER TROPOSPHERIC FLOW WILL PREVENT AN EASTWARD PUSH OF
CONVECTION FAR INTO WESTERN KANSAS. AS A RESULT...SLIGHT CHANCE
POPS WILL BE CONFINED ONLY TO FAR WEST-CENTRAL AND SOUTHWEST KANSAS.
A COLD FRONT PUSH LATE TUESDAY AND WEDNESDAY WOULD LEAD TO AN
INCREASED CHANCE FOR THUNDERSTORMS OVER A LARGER PORTION OF
SOUTHWEST KANSAS AS SUGGESTED BY THE LATEST ECMWF MODEL (AS A
STRONGER SHORTWAVE TROUGH/UPPER LOW DEVELOPS ACROSS THE NORTHERN
DAKOTAS ADJACENT CANADA INTO THE UPPER MIDWEST REGION). SHOULD THE
FRONT PENETRATE KANSAS MID-WEEK...AFTERNOON TEMPERATURES WILL BE
COOLER WITH HIGHS IN THE LOWER TO MID 90S INSTEAD OF THE LOW 100S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1214 PM CDT FRI JUL 5 2013
VFR CONDITIONS WILL CONTINUE THROUGH 18Z SATURDAY. A FEW
ALTOCUMULUS CLOUDS IN THE 100-120 THOUSAND FOOT RANGE, AND PASSING
CIRRUS CLOUDS IN THE 200-250 THOUSAND FOOT RANGE WILL BE AROUND
TONIGHT. THE CIRRUS CLOUDS MAY GO BROKEN AFTER 14Z SATURDAY. THE
BREEZY SOUTH WINDS THIS AFTERNOON IN THE 15G25KT RANGE WILL
SUBSIDE TO SOUTHEAST AT 13 TO 25 KNOTS AFTER 00Z. WINDS ON
SATURDAY WILL BE STRONG FROM THE SOUTH, AND GENERALLY IN THE
20G30KT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 68 100 70 / 10 10 10 10
GCK 97 69 100 69 / 10 10 10 20
EHA 97 68 98 70 / 10 10 20 20
LBL 97 66 100 70 / 10 10 10 10
HYS 97 69 100 71 / 10 10 10 10
P28 95 69 100 73 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HOVORKA_42
SHORT TERM...HOVORKA_42
LONG TERM...UMSCHEID
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
656 AM CDT FRI JUL 5 2013
...UPDATED AVIATION SECTION...
.SYNOPSIS...
ISSUED AT 1000 PM CDT THU JUL 4 2013
THE 05.00Z 250 HPA RAOB MAP SHOWED A RATHER STAGNANT UPPER AIR FLOW
PATTERN AS COMPARED TO THE 04.00Z RAOBS. BASICALLY, ANTICYCLONIC FLOW
PREVAILED ACROSS THE WESTERN UNITED STATES AND MERIDIONAL FLOW CONTINUED
FARTHER DOWNSTREAM. MAGNITUDES WERE 70 KT (@72768) ON THE TOP OF THE
RIDGE AND THE STRONGEST SOUTHERLY FLOW DOWNSTREAM WAS AROUND 115 KT
(@72645). @ 500 HPA, THE CENTER OF A 592 DM ANTICYCLONE WAS NEAR 72388.
FAIRLY WARM MID LEVEL TEMPERATURES OF -5 DEG C WERE ASSOCIATED WITH
SAID PRESSURE PERTURBATION. DOWNSTREAM, A BROAD TROF EXTENDED ROUGHLY
FROM 72440 TO 72645. TEMPERATURES WERE IN THE -13 TO -14 DEG C RANGE.
AT 700 HPA, 2 DEGREES C OF WARMING WERE NOTED AT 72451 IN COMPARING
04.00Z AND 05.00Z RAOBS. SAME ORDER OF MAGNITUDE OF WARMING WAS NOTED
AT 850 HPA FOR THE SAME UPPER AIR SITE. AT THE SFC, A LEE SURFACE TROF
WAS ANALYZED ACROSS SE COLORADO. A COLD FRONT EXTENDED FROM EASTERN NORTH
DAKOTA SOUTHWARD TO THE NEBRASKA PANHANDLE. TROPICAL DEPRESSION DALILA WAS
LOCATED NEAR 17.3N 111.0W @ 05.03Z AND TROPICAL STORM ERICK WAS LOCATED
NEAR 14.9N 100.0W @ 05.03Z
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 100 AM CDT FRI JUL 5 2013
THIS MORNING:
THE FORECAST THIS MORNING IS RATHER UNCOMPLICATED AND STRAIGHT FORWARD.
THE HRRR AND TO A LESSER EXTENT THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS SOME QPF ACROSS THE REGION THIS MORNING. SATELLITE WATER VAPOR
IMAGERY SHOWS A SMALL PERTURBATION MOVING ACROSS THE REGION THIS MORNING
IN THE NORTHERLY FLOW ALOFT. IN ADDITION, KDDC WSR- 88D VAD PROFILE
SHOWS A STRENGTHENING 850 HPA LOW LEVEL JET THROUGH 05Z. FEEL THAT THE
HRRR IS A BIT AGGRESSIVE WITH QPF. THE NAM IS MORE CONSERVATIVE AND
KEEPS ANY PRECIPITATION THIS MORNING CLOSER THE TROF MENTIONED IN THE
SYNOPSIS. AS A RESULT, WILL KEEP PROBABILITY PRECIPITATION PERCENTAGE
POINTS AT OR BELOW 14 PERCENT DUE TO DISAGREEMENT IN THE MESOSCALE MODELS.
OTHER MESOSCALE MODELS SUCH AS THE WRF-ARW DO NOT SHOW ANYTHING EXCITING
DURING THIS PERIOD.
TODAY:
NEAR NEUTRAL 500 HPA GEOPOTENTIAL HEIGHT TENDENCIES ARE EXPECTED TODAY.
AT THE SFC, A LEE TROUGH WILL CONTINUE ACROSS EASTERN COLORADO. THE
NET RESULT IS PRETTY MUCH A CARBON COPY OF YESTERDAYS SENSIBLE WEATHER
FOR TODAY... ERGO A FEW CLOUDS AND BREEZY SOUTHERLY WINDS. MAXIMUM TEMPERATURES
WILL BE HIGHER THAN COMPARED TO YESTERDAY AND IN THE MID 90S AS THE
850 HPA WARM PLUME ADVECTS FARTHER EAST. EVEN THOUGH IT WILL BE VERY
WARM TO HOT AND BREEZY, CRITICAL FIRE WEATHER CONDITIONS ARE NOT EXPECTED
TODAY AS DOWNSLOPE SOUTHWESTERLY WINDS ARE NOT EXPECTED WHICH IS THE
MOST IDEAL FOR RED FLAG WARNING CONDITIONS.
TONIGHT:
BY DUSK, WINDS SHOULD ABATE AS THE BOUNDARY LAYER DECOUPLES WITH SOUTHERLY
WINDS OF MAGNITUDES 10-18 MPH IS EXPECTED THROUGH LATE EVENING. THE
OPERATIONAL 05.00Z NAM RUN SHOWS THE POSSIBILITY OF CONVECTION ACROSS
WESTERN KANSAS TONIGHT. THE NESTED 05.00Z 4 KM NAM KEEPS CONVECTION
ACROSS EASTERN COLORADO. GIVEN THE WEAK FLOW ALOFT AND EXPECTED CONVERGENCE
FARTHER WEST, WILL KEEP PRECIPITATION PROBABILITY PERCENTAGE POINTS
AT OR BELOW 14 PERCENT. EVEN TAKING THE OPERATIONAL RUN OF THE NAM AT
FACE VALUE, AN INSPECTION OF FORECAST SKEW T/LOG-P`S SHOW WEAK INSTABILITY.
OTHERWISE, MINIMUMS HEADING INTO SATURDAY MORNING WILL BE IN THE UPPER
60S DEG F.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 AM CDT FRI JUL 5 2013
A RATHER TYPICAL SUMMER PATTERN WILL PREVAIL ACROSS THE SOUTHWEST
KANSAS REGION FROM SATURDAY THROUGH MID NEXT WEEK. THE 500MB HIGH
OVER THE WEEKEND WILL BE CENTERED ACROSS THE ARIZONA-NEW MEXICO
BORDER REGION WITH A WEAK JET CORE MOVING ACROSS THE NORTHERN
ROCKIES INTO THE DAKOTAS. THE RIDGE WILL BECOME FAIRLY FLAT GOING
INTO EARLY NEXT WEEK FROM ARIZONA/NEW MEXICO INTO OKLAHOMA AS ZONAL
FLOW PREVAILS ACROSS THE NORTHERN CONUS. THIS PATTERN WILL LEAD TO A
SUSTAINED LEE TROUGH FEATURE WITH A WEAK FRONTAL PUSH AS WEAK
SHORTWAVE TROUGHS MOVE ACROSS THE NORTHERN PLAINS WITHIN THE ZONAL
JET STREAM. NONE OF THESE FRONTAL SURGES ARE EXPECTED TO REACH
SOUTHERN KANSAS GIVEN THE STRENGTH OF THE SUBTROPICAL RIDGING FROM
THE DESERT SOUTHWEST REGION INTO THE SOUTHERN PLAINS. FROM SATURDAY
THROUGH TUESDAY...THIS PATTERN WILL YIELD AFTERNOON TEMPERATURES IN
THE UPPER 90S TO AROUND 100 DEGREES WITH OVERNIGHT LOWS WARM IN THE
LOWER TO PERHAPS MID 70S. DIURNAL CONVECTION WILL BE POSSIBLE EACH
DAY ALONG THE LEE TROUGH CONVERGENCE AXIS (AND MORE LIKELY OVER
TERRAIN-FAVORED REGIONS OF COLORADO)...BUT THE OVERALL WEAK
MID-UPPER TROPOSPHERIC FLOW WILL PREVENT AN EASTWARD PUSH OF
CONVECTION FAR INTO WESTERN KANSAS. AS A RESULT...SLIGHT CHANCE
POPS WILL BE CONFINED ONLY TO FAR WEST-CENTRAL AND SOUTHWEST KANSAS.
A COLD FRONT PUSH LATE TUESDAY AND WEDNESDAY WOULD LEAD TO AN
INCREASED CHANCE FOR THUNDERSTORMS OVER A LARGER PORTION OF
SOUTHWEST KANSAS AS SUGGESTED BY THE LATEST ECMWF MODEL (AS A
STRONGER SHORTWAVE TROUGH/UPPER LOW DEVELOPS ACROSS THE NORTHERN
DAKOTAS ADJACENT CANADA INTO THE UPPER MIDWEST REGION). SHOULD THE
FRONT PENETRATE KANSAS MID-WEEK...AFTERNOON TEMPERATURES WILL BE
COOLER WITH HIGHS IN THE LOWER TO MID 90S INSTEAD OF THE LOW 100S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 652 AM CDT FRI JUL 5 2013
STATUS-QUO AS FAR AS AVIATION WEATHER IS CONCERNED. PREVAILING
WIND DIRECTION WILL REMAIN SOUTH TODAY AND INTO THIS EVENING AS A
LEE TROUGH REMAINS ACROSS FAR EASTERN COLORADO. WIND SPEEDS WILL
INCREASE TO AROUND 20 KNOTS SUSTAINED BY LATE MORNING OR MIDDAY.
ANY THUNDERSTORM ACTIVITY SHOULD REMAIN ACROSS EASTERN COLORADO
AND NOT AFFECT ANY OF THE TERMINALS (GCK, DDC, HYS).
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 68 100 73 / 10 10 10 10
GCK 97 69 100 72 / 10 10 10 10
EHA 97 68 98 72 / 10 10 20 20
LBL 97 66 100 72 / 10 10 10 10
HYS 97 69 100 74 / 10 10 10 10
P28 95 69 100 74 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HOVORKA_42
SHORT TERM...HOVORKA_42
LONG TERM...UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
325 AM CDT FRI JUL 5 2013
...UPDATED LONG TERM SECTION...
.SYNOPSIS...
ISSUED AT 1000 PM CDT THU JUL 4 2013
THE 05.00Z 250 HPA RAOB MAP SHOWED A RATHER STAGNANT UPPER AIR FLOW
PATTERN AS COMPARED TO THE 04.00Z RAOBS. BASICALLY, ANTICYCLONIC FLOW
PREVAILED ACROSS THE WESTERN UNITED STATES AND MERIDIONAL FLOW CONTINUED
FARTHER DOWNSTREAM. MAGNITUDES WERE 70 KT (@72768) ON THE TOP OF THE
RIDGE AND THE STRONGEST SOUTHERLY FLOW DOWNSTREAM WAS AROUND 115 KT
(@72645). @ 500 HPA, THE CENTER OF A 592 DM ANTICYCLONE WAS NEAR 72388.
FAIRLY WARM MID LEVEL TEMPERATURES OF -5 DEG C WERE ASSOCIATED WITH
SAID PRESSURE PERTURBATION. DOWNSTREAM, A BROAD TROF EXTENDED ROUGHLY
FROM 72440 TO 72645. TEMPERATURES WERE IN THE -13 TO -14 DEG C RANGE.
AT 700 HPA, 2 DEGREES C OF WARMING WERE NOTED AT 72451 IN COMPARING
04.00Z AND 05.00Z RAOBS. SAME ORDER OF MAGNITUDE OF WARMING WAS NOTED
AT 850 HPA FOR THE SAME UPPER AIR SITE. AT THE SFC, A LEE SURFACE TROF
WAS ANALYZED ACROSS SE COLORADO. A COLD FRONT EXTENDED FROM EASTERN NORTH
DAKOTA SOUTHWARD TO THE NEBRASKA PANHANDLE. TROPICAL DEPRESSION DALILA WAS
LOCATED NEAR 17.3N 111.0W @ 05.03Z AND TROPICAL STORM ERICK WAS LOCATED
NEAR 14.9N 100.0W @ 05.03Z
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 100 AM CDT FRI JUL 5 2013
THIS MORNING:
THE FORECAST THIS MORNING IS RATHER UNCOMPLICATED AND STRAIGHT FORWARD.
THE HRRR AND TO A LESSER EXTENT THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS SOME QPF ACROSS THE REGION THIS MORNING. SATELLITE WATER VAPOR
IMAGERY SHOWS A SMALL PERTURBATION MOVING ACROSS THE REGION THIS MORNING
IN THE NORTHERLY FLOW ALOFT. IN ADDITION, KDDC WSR- 88D VAD PROFILE
SHOWS A STRENGTHENING 850 HPA LOW LEVEL JET THROUGH 05Z. FEEL THAT THE
HRRR IS A BIT AGGRESSIVE WITH QPF. THE NAM IS MORE CONSERVATIVE AND
KEEPS ANY PRECIPITATION THIS MORNING CLOSER THE TROF MENTIONED IN THE
SYNOPSIS. AS A RESULT, WILL KEEP PROBABILITY PRECIPITATION PERCENTAGE
POINTS AT OR BELOW 14 PERCENT DUE TO DISAGREEMENT IN THE MESOSCALE MODELS.
OTHER MESOSCALE MODELS SUCH AS THE WRF-ARW DO NOT SHOW ANYTHING EXCITING
DURING THIS PERIOD.
TODAY:
NEAR NEUTRAL 500 HPA GEOPOTENTIAL HEIGHT TENDENCIES ARE EXPECTED TODAY.
AT THE SFC, A LEE TROUGH WILL CONTINUE ACROSS EASTERN COLORADO. THE
NET RESULT IS PRETTY MUCH A CARBON COPY OF YESTERDAYS SENSIBLE WEATHER
FOR TODAY... ERGO A FEW CLOUDS AND BREEZY SOUTHERLY WINDS. MAXIMUM TEMPERATURES
WILL BE HIGHER THAN COMPARED TO YESTERDAY AND IN THE MID 90S AS THE
850 HPA WARM PLUME ADVECTS FARTHER EAST. EVEN THOUGH IT WILL BE VERY
WARM TO HOT AND BREEZY, CRITICAL FIRE WEATHER CONDITIONS ARE NOT EXPECTED
TODAY AS DOWNSLOPE SOUTHWESTERLY WINDS ARE NOT EXPECTED WHICH IS THE
MOST IDEAL FOR RED FLAG WARNING CONDITIONS.
TONIGHT:
BY DUSK, WINDS SHOULD ABATE AS THE BOUNDARY LAYER DECOUPLES WITH SOUTHERLY
WINDS OF MAGNITUDES 10-18 MPH IS EXPECTED THROUGH LATE EVENING. THE
OPERATIONAL 05.00Z NAM RUN SHOWS THE POSSIBILITY OF CONVECTION ACROSS
WESTERN KANSAS TONIGHT. THE NESTED 05.00Z 4 KM NAM KEEPS CONVECTION
ACROSS EASTERN COLORADO. GIVEN THE WEAK FLOW ALOFT AND EXPECTED CONVERGENCE
FARTHER WEST, WILL KEEP PRECIPITATION PROBABILITY PERCENTAGE POINTS
AT OR BELOW 14 PERCENT. EVEN TAKING THE OPERATIONAL RUN OF THE NAM AT
FACE VALUE, AN INSPECTION OF FORECAST SKEW T/LOG-P`S SHOW WEAK INSTABILITY.
OTHERWISE, MINIMUMS HEADING INTO SATURDAY MORNING WILL BE IN THE UPPER
60S DEG F.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 322 AM CDT FRI JUL 5 2013
A RATHER TYPICAL SUMMER PATTERN WILL PREVAIL ACROSS THE SOUTHWEST
KANSAS REGION FROM SATURDAY THROUGH MID NEXT WEEK. THE 500MB HIGH
OVER THE WEEKEND WILL BE CENTERED ACROSS THE ARIZONA-NEW MEXICO
BORDER REGION WITH A WEAK JET CORE MOVING ACROSS THE NORTHERN
ROCKIES INTO THE DAKOTAS. THE RIDGE WILL BECOME FAIRLY FLAT GOING
INTO EARLY NEXT WEEK FROM ARIZONA/NEW MEXICO INTO OKLAHOMA AS ZONAL
FLOW PREVAILS ACROSS THE NORTHERN CONUS. THIS PATTERN WILL LEAD TO A
SUSTAINED LEE TROUGH FEATURE WITH A WEAK FRONTAL PUSH AS WEAK
SHORTWAVE TROUGHS MOVE ACROSS THE NORTHERN PLAINS WITHIN THE ZONAL
JET STREAM. NONE OF THESE FRONTAL SURGES ARE EXPECTED TO REACH
SOUTHERN KANSAS GIVEN THE STRENGTH OF THE SUBTROPICAL RIDGING FROM
THE DESERT SOUTHWEST REGION INTO THE SOUTHERN PLAINS. FROM SATURDAY
THROUGH TUESDAY...THIS PATTERN WILL YIELD AFTERNOON TEMPERATURES IN
THE UPPER 90S TO AROUND 100 DEGREES WITH OVERNIGHT LOWS WARM IN THE
LOWER TO PERHAPS MID 70S. DIURNAL CONVECTION WILL BE POSSIBLE EACH
DAY ALONG THE LEE TROUGH CONVERGENCE AXIS (AND MORE LIKELY OVER
TERRAIN-FAVORED REGIONS OF COLORADO)...BUT THE OVERALL WEAK
MID-UPPER TROPOSPHERIC FLOW WILL PREVENT AN EASTWARD PUSH OF
CONVECTION FAR INTO WESTERN KANSAS. AS A RESULT...SLIGHT CHANCE
POPS WILL BE CONFINED ONLY TO FAR WEST-CENTRAL AND SOUTHWEST KANSAS.
A COLD FRONT PUSH LATE TUESDAY AND WEDNESDAY WOULD LEAD TO AN
INCREASED CHANCE FOR THUNDERSTORMS OVER A LARGER PORTION OF
SOUTHWEST KANSAS AS SUGGESTED BY THE LATEST ECMWF MODEL (AS A
STRONGER SHORTWAVE TROUGH/UPPER LOW DEVELOPS ACROSS THE NORTHERN
DAKOTAS ADJACENT CANADA INTO THE UPPER MIDWEST REGION). SHOULD THE
FRONT PENETRATE KANSAS MID-WEEK...AFTERNOON TEMPERATURES WILL BE
COOLER WITH HIGHS IN THE LOWER TO MID 90S INSTEAD OF THE LOW 100S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1200 AM CDT FRI JUL 5 2013
VFR CIGS EXPECTED THRU TAF PD. THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS OROGRAPHIC CONVECTION WEST OF KGCK THIS EVENING. THE NESTED 4
KM NAM KEEPS CONVECTION ACROSS COLORADO. THIS SECOND SOLUTION LOOKS
MORE REASONABLE AT THIS TIME, GIVEN NEAR NEUTRAL 500 HPA GEOPOTENTIAL
HEIGHT TENDENCIES. WILL INTRODUCE A MID DECK FOR KGCK NOW AND KEEP KDDC/KHYS
CAVU. WIND VECTORS SOUTHERLY WITH 10-20 KT MAGNITUDES, STRONGEST 15Z-
23Z IN ASSOCIATION WITH MIXING/MOMENTUM TRANSFER DOWNWARD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 96 68 100 73 / 10 10 10 10
GCK 97 69 100 72 / 10 10 10 10
EHA 97 68 98 72 / 10 10 20 20
LBL 97 66 100 72 / 10 10 10 10
HYS 97 69 100 74 / 10 10 10 10
P28 95 69 100 74 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HOVORKA_42
SHORT TERM...HOVORKA_42
LONG TERM...UMSCHEID
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS GOODLAND KS
219 AM MDT FRI JUL 5 2013
.UPDATE...
ISSUED AT 642 PM MDT THU JUL 4 2013
JUST COMPLETED AN UPDATE. SURFACE TROUGH WEAK SHORTWAVE TROUGH/UPPER
JET ARE CAUSING ISOLATED THUNDERSTORMS OVER THE NORTHERN AND
WESTERN PORTIONS OF THE AREA. LATEST HRRR HAS THE BEST HANDLE ON
THIS. AS HEATING OF THE DAY GOES AWAY AND THE BEST LIFT MOVES AWAY
FROM THE AREA...STORMS SHOULD DECREASE AND BE DONE BY 04Z. THERE
IS A LOT OF HIGHER LEVEL CLOUD COVER DUE TO THE CONVECTION/SHORTWAVE
TROUGH. SO INCREASED THE SKY COVER THROUGH THE EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 1204 PM MDT THU JUL 4 2013
UPPER RIDGE WILL GRADUALLY BUILD EASTWARD ACROSS THE CENTRAL
ROCKIES AND ADJACENT PLAINS THROUGH FRIDAY. THIS WILL ALLOW
TEMPERATURES TO CLIMB TO ABOVE NORMAL AND SUPPRESS MOST IF NOT ALL
CHANCES FOR CONVECTION. HOWEVER...A FEW STORMS ARE FORECAST TO
DEVELOP ALONG THE FRONT RANGE FRIDAY AFTERNOON WITH A VERY SLIM
CHANCE THAT THEY MIGHT REACH FAR NORTHEAST COLORADO BY LATE FRIDAY
AFTERNOON. IN ADDITION...NORTHEAST COLORADO WILL SEE RH VALUES
DROP TO THE 15 TO 20 PERCENT RANGE FRIDAY AFTERNOON...BUT THESE
AREAS WILL SEE THE LEAST WIND AT AROUND 15KTS...RESULTING IN
MARGINAL FIRE WEATHER CONDITIONS THAT WILL NEED TO BE MONITORED
GIVEN DRY FUELS IN THOSE AREAS.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 217 AM MDT FRI JUL 5 2013
THE UPPER FLOW PATTERN AT 500 MB FOR THE LONG TERM PERIOD WILL HAVE
A HIGH PRESSURE RIDGE SLOWLY WEAKEN AND RETURN TO A ZONAL FLOW
PATTERN. THE CENTRAL PLAINS WILL SEE SHORTWAVE TROUGH ACTIVITY EACH
DAY THROUGH THE PERIOD...WHICH WILL HELP WITH DESTABILIZATION AND
CONVECTION DEVELOPMENT. RIDGE WILL STRENGTHEN FOR THE END OF NEXT WEEK
WITH THE CENTER AXIS BUILDING INTO THE CENTRAL PLAINS...BUT
NUMEROUS SHORTWAVE TROUGHS WILL BE EMBEDDED IN MAIN FLOW. JET
STREAM SHOULD REMAIN WELL TO THE NORTH OF THE TRI STATE AREA.
STRONG LOWER LEVEL NOCTURNAL JETS FOR THE AREA WILL DEVELOP IN THE
OVERNIGHT HOURS...WHICH COULD HELP MAINTAIN CONVECTION THAT STARTS
IN THE EVENING HOURS.
SURFACE LOW PRESSURE ALONG THE COLORADO FRONT RANGE WILL HELP
PROVIDE WARM AIR ADVECTION AND STRONG SOUTHERLY FLOW TO THE TRI
STATE AREA THROUGH THE EXTENDED FORECAST PERIOD. INSTABILITY
PARAMETERS ARE SUPPORTIVE OF CONVECTIVE DEVELOPMENT...ALTHOUGH
STRONG FORCING THROUGH THE PERIOD LOOKS TO BE ABSENT. ISOLATED
THUNDERSTORMS ARE POSSIBLE FOR EVERY TIME PERIOD AND MOST LOCATIONS
THROUGHOUT NEXT WEEK. BEST CHANCE TO SEE SOME PRECIPITATION FOR THE
AREA WOULD BE TUESDAY AS A WEAK FRONTAL SYSTEM MOVES THROUGH THE
HIGH PLAINS. 850 MB TEMPERATURES LOOK TO BE WARM WITH VALUES OF 85 TO
88...AND SURFACE TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL
REACHING THE UPPER 90S FOR MOST LOCATIONS. TEMPERATURES MAY SLIGHTLY
COOL TO NEAR NORMAL WITH VALUES IN THE LOWER 90S FOR LATER IN THE
WEEK. OTHER THAN ISOLATED THUNDERSTORM ACTIVITY ACROSS THE CWA NEXT
WEEK...SUNNY AND WARM CONDITIONS ARE EXPECTED TO BE THE MAIN WEATHER
CONDITIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1125 PM MDT THU JUL 4 2013
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BECOME
GUSTY ONCE THE MIXING BEGINS. THE GUSTINESS OF THE WINDS WILL END
DURING THE EARLY EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...024
LONG TERM...MK
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
100 AM CDT FRI JUL 5 2013
...UPDATE TO SHORT TERM DISCUSSION...
.SYNOPSIS...
ISSUED AT 1000 PM CDT THU JUL 4 2013
THE 05.00Z 250 HPA RAOB MAP SHOWED A RATHER STAGNANT UPPER AIR FLOW
PATTERN AS COMPARED TO THE 04.00Z RAOBS. BASICALLY, ANTICYCLONIC FLOW
PREVAILED ACROSS THE WESTERN UNITED STATES AND MERIDIONAL FLOW CONTINUED
FARTHER DOWNSTREAM. MAGNITUDES WERE 70 KT (@72768) ON THE TOP OF THE
RIDGE AND THE STRONGEST SOUTHERLY FLOW DOWNSTREAM WAS AROUND 115 KT
(@72645). @ 500 HPA, THE CENTER OF A 592 DM ANTICYCLONE WAS NEAR 72388.
FAIRLY WARM MID LEVEL TEMPERATURES OF -5 DEG C WERE ASSOCIATED WITH
SAID PRESSURE PERTURBATION. DOWNSTREAM, A BROAD TROF EXTENDED ROUGHLY
FROM 72440 TO 72645. TEMPERATURES WERE IN THE -13 TO -14 DEG C RANGE.
AT 700 HPA, 2 DEGREES C OF WARMING WERE NOTED AT 72451 IN COMPARING
04.00Z AND 05.00Z RAOBS. SAME ORDER OF MAGNITUDE OF WARMING WAS NOTED
AT 850 HPA FOR THE SAME UPPER AIR SITE. AT THE SFC, A LEE SURFACE TROF
WAS ANALYZED ACROSS SE COLORADO. A COLD FRONT EXTENDED FROM EASTERN NORTH
DAKOTA SOUTHWARD TO THE NEBRASKA PANHANDLE. TROPICAL DEPRESSION DALILA WAS
LOCATED NEAR 17.3N 111.0W @ 05.03Z AND TROPICAL STORM ERICK WAS LOCATED
NEAR 14.9N 100.0W @ 05.03Z
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 100 AM CDT FRI JUL 5 2013
THIS MORNING:
THE FORECAST THIS MORNING IS RATHER UNCOMPLICATED AND STRAIGHT FORWARD.
THE HRRR AND TO A LESSER EXTENT THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS SOME QPF ACROSS THE REGION THIS MORNING. SATELLITE WATER VAPOR
IMAGERY SHOWS A SMALL PERTURBATION MOVING ACROSS THE REGION THIS MORNING
IN THE NORTHERLY FLOW ALOFT. IN ADDITION, KDDC WSR- 88D VAD PROFILE
SHOWS A STRENGTHENING 850 HPA LOW LEVEL JET THROUGH 05Z. FEEL THAT THE
HRRR IS A BIT AGGRESSIVE WITH QPF. THE NAM IS MORE CONSERVATIVE AND
KEEPS ANY PRECIPITATION THIS MORNING CLOSER THE TROF MENTIONED IN THE
SYNOPSIS. AS A RESULT, WILL KEEP PROBABILITY PRECIPITATION PERCENTAGE
POINTS AT OR BELOW 14 PERCENT DUE TO DISAGREEMENT IN THE MESOSCALE MODELS.
OTHER MESOSCALE MODELS SUCH AS THE WRF-ARW DO NOT SHOW ANYTHING EXCITING
DURING THIS PERIOD.
TODAY:
NEAR NEUTRAL 500 HPA GEOPOTENTIAL HEIGHT TENDENCIES ARE EXPECTED TODAY.
AT THE SFC, A LEE TROUGH WILL CONTINUE ACROSS EASTERN COLORADO. THE
NET RESULT IS PRETTY MUCH A CARBON COPY OF YESTERDAYS SENSIBLE WEATHER
FOR TODAY... ERGO A FEW CLOUDS AND BREEZY SOUTHERLY WINDS. MAXIMUM TEMPERATURES
WILL BE HIGHER THAN COMPARED TO YESTERDAY AND IN THE MID 90S AS THE
850 HPA WARM PLUME ADVECTS FARTHER EAST. EVEN THOUGH IT WILL BE VERY
WARM TO HOT AND BREEZY, CRITICAL FIRE WEATHER CONDITIONS ARE NOT EXPECTED
TODAY AS DOWNSLOPE SOUTHWESTERLY WINDS ARE NOT EXPECTED WHICH IS THE
MOST IDEAL FOR RED FLAG WARNING CONDITIONS.
TONIGHT:
BY DUSK, WINDS SHOULD ABATE AS THE BOUNDARY LAYER DECOUPLES WITH SOUTHERLY
WINDS OF MAGNITUDES 10-18 MPH IS EXPECTED THROUGH LATE EVENING. THE
OPERATIONAL 05.00Z NAM RUN SHOWS THE POSSIBILITY OF CONVECTION ACROSS
WESTERN KANSAS TONIGHT. THE NESTED 05.00Z 4 KM NAM KEEPS CONVECTION
ACROSS EASTERN COLORADO. GIVEN THE WEAK FLOW ALOFT AND EXPECTED CONVERGENCE
FARTHER WEST, WILL KEEP PRECIPITATION PROBABILITY PERCENTAGE POINTS
AT OR BELOW 14 PERCENT. EVEN TAKING THE OPERATIONAL RUN OF THE NAM AT
FACE VALUE, AN INSPECTION OF FORECAST SKEW T/LOG-P`S SHOW WEAK INSTABILITY.
OTHERWISE, MINIMUMS HEADING INTO SATURDAY MORNING WILL BE IN THE UPPER
60S DEG F.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 240 PM CDT THU JUL 4 2013
AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL TREK EASTWARD AND
ELONGATE DURING THE EXTENDED PERIOD. THIS RIDGE WILL START OUT IN
THE SOUTHERN ROCKIES FRIDAY NIGHT INTO SATURDAY THEN INTO THE PLAINS
SUNDAY INTO THE FIRST PART OF NEXT WEEK. A FEW WEAK DISTURBANCES ARE
FORECASTED TO MOVE AROUND THE PERIPHERY OF THIS RIDGE STARTING
SATURDAY AFTERNOON AND INCREASE THUNDERSTORM CHANCES ACROSS NORTHERN
KANSAS. A FEW OF THESE STORMS MAY ALSO DEVELOP ACROSS EASTERN
COLORADO AND MOVE INTO FAR WESTERN KANSAS. OTHERWISE EXPECT PARTLY
CLOUDY SKIES ACROSS WESTERN KANSAS THROUGH TUESDAY. THE UPPER LEVEL
RIDGE OF HIGH PRESSURE IS THEN ANTICIPATED TO RETROGRADE BACK TO THE
WEST TUESDAY NIGHT INTO THE REMAINDER OF THE WEEK BRINGING WEAK
DISTURBANCES FARTHER SOUTH AND ACROSS THE FORECAST AREA. THIS WILL
INCREASE THE CHANCE OF RAIN ACROSS THE REMAINDER OF THE CWA. SURFACE
WINDS THROUGHOUT THE EXTENDED PERIOD WILL GENERALLY BE FROM THE
SOUTH AS HIGH PRESSURE REMAINS POSITIONED EAST OF THE AREA AND
TROUGHING CONTINUES ACROSS EASTERN COLORADO. HIGHS SATURDAY THROUGH
WEDNESDAY WILL GENERALLY BE IN THE UPPER 90S WITH A FEW AREAS
REACHING THE TRIPLE DIGIT MARK. LOWS WILL GENERALLY BE IN THE LOWER
TO MID 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1200 AM CDT FRI JUL 5 2013
VFR CIGS EXPECTED THRU TAF PD. THE OPERATIONAL RUN OF THE 05.00Z NAM
SHOWS OROGRAPHIC CONVECTION WEST OF KGCK THIS EVENING. THE NESTED 4
KM NAM KEEPS CONVECTION ACROSS COLORADO. THIS SECOND SOLUTION LOOKS
MORE REASONABLE AT THIS TIME, GIVEN NEAR NEUTRAL 500 HPA GEOPOTENTIAL
HEIGHT TENDENCIES. WILL INTRODUCE A MID DECK FOR KGCK NOW AND KEEP KDDC/KHYS
CAVU. WIND VECTORS SOUTHERLY WITH 10-20 KT MAGNITUDES, STRONGEST 15Z-
23Z IN ASSOCIATION WITH MIXING/MOMENTUM TRANSFER DOWNWARD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 98 73 99 / 10 10 10 10
GCK 69 98 72 98 / 10 10 10 20
EHA 68 96 72 96 / 10 10 10 20
LBL 66 98 72 99 / 10 10 10 10
HYS 69 98 74 99 / 10 10 10 20
P28 69 97 74 100 / 10 10 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HOVORKA_42
SHORT TERM...HOVORKA_42
LONG TERM...SUGDEN
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1129 PM MDT THU JUL 4 2013
.UPDATE...
ISSUED AT 642 PM MDT THU JUL 4 2013
JUST COMPLETED AN UPDATE. SURFACE TROUGH WEAK SHORTWAVE TROUGH/UPPER
JET ARE CAUSING ISOLATED THUNDERSTORMS OVER THE NORTHERN AND
WESTERN PORTIONS OF THE AREA. LATEST HRRR HAS THE BEST HANDLE ON
THIS. AS HEATING OF THE DAY GOES AWAY AND THE BEST LIFT MOVES AWAY
FROM THE AREA...STORMS SHOULD DECREASE AND BE DONE BY 04Z. THERE
IS A LOT OF HIGHER LEVEL CLOUD COVER DUE TO THE CONVECTION/SHORTWAVE
TROUGH. SO INCREASED THE SKY COVER THROUGH THE EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 1204 PM MDT THU JUL 4 2013
UPPER RIDGE WILL GRADUALLY BUILD EASTWARD ACROSS THE CENTRAL
ROCKIES AND ADJACENT PLAINS THROUGH FRIDAY. THIS WILL ALLOW
TEMPERATURES TO CLIMB TO ABOVE NORMAL AND SUPPRESS MOST IF NOT ALL
CHANCES FOR CONVECTION. HOWEVER...A FEW STORMS ARE FORECAST TO
DEVELOP ALONG THE FRONT RANGE FRIDAY AFTERNOON WITH A VERY SLIM
CHANCE THAT THEY MIGHT REACH FAR NORTHEAST COLORADO BY LATE FRIDAY
AFTERNOON. IN ADDITION...NORTHEAST COLORADO WILL SEE RH VALUES
DROP TO THE 15 TO 20 PERCENT RANGE FRIDAY AFTERNOON...BUT THESE
AREAS WILL SEE THE LEAST WIND AT AROUND 15KTS...RESULTING IN
MARGINAL FIRE WEATHER CONDITIONS THAT WILL NEED TO BE MONITORED
GIVEN DRY FUELS IN THOSE AREAS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 203 PM MDT THU JUL 4 2013
UNSETTLED PATTERN CONTINUES THROUGH THE MIDDLE OF NEXT WEEK WITH
AT LEAST ISOLATED THUNDERSTORMS POSSIBLE EACH FORECAST PERIOD.
H5 RIDGE STILL EXPECTED TO DEAMPLIFY WITH WESTERLY FLOW DEVELOPING
ACROSS NORTHERN PLAINS. MODEL TRENDS HAVE SHIFTED MEAN FLOW
SLIGHTLY NORTH...WHICH COULD ALLOW RIDGE TO HOLD MORE INFLUENCE
OVER OUR CWA...AND DECREASE CHANCES. AT THE SAME TIME MODELS
CONTINUE TO SHOW SERIES OF SHORTWAVE TROUGHS/VORT MAXES PASSING
OVER CWA AND PRODUCING QPF EVERY PERIOD. MIXING HEIGHTS AND DRY
ADIABATIC LAYER IN PLACE WOULD SUPPORT THE FORMATION OF A FAIRLY
STRONG DRYLINE ALONG THE KS/CO BORDER...HOWEVER MODEL 2M TD VALUES
ARE STILL MUCH HIGHER. ELEVATED INSTABILITY SHOULD LINGER
OVERNIGHT WITH SUPPORT FROM LLJ AND H85-H5 ISENTROPIC FORCING...SO
I CANT RULE OUT THUNDERSTORM CHANCES ANY PERIOD. A WEAK COLD FRONT
WILL SETTLE SOUTH AND STALL ACROSS SW NEBRASKA MON/TUE AND COULD
ACT AS A FOCUS FOR THUNDERSTORM INITIATION THROUGH THE MIDDLE OF
NEXT WEEK. DUE TO UNCERTAINTIES REGARDING INITIATION EACH PERIOD I
DIDNT WANT TO INCREASE POPS OUTSIDE OF CHANCE CATEGORY.
TEMPS REMAIN ABOVE NORMAL SAT/SUN WITH SOME LOCATIONS LIKELY
APPROACHING TRIPLE DIGITS. THERE IS LESS CERTAINTY WITH TEMPS MON
DUE TO FRONTAL POSITION DIFFERENCES HOWEVER WE SHOULD STILL SEE
TEMPS APPROACH THE MID 90S. AT THIS POINT WE PROBABLY WONT SEE
NORMAL TEMPS IN THE UPPER 80S/NEAR 90F UNTIL WED/THU WHEN GUIDANCE
SHOWS STRONGER TROUGH DIGGING INTO THE NORTHERN PLAINS AND HEIGHTS
FALLING OVER OUR CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1125 PM MDT THU JUL 4 2013
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BECOME
GUSTY ONCE THE MIXING BEGINS. THE GUSTINESS OF THE WINDS WILL END
DURING THE EARLY EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...024
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
125 PM EDT FRI JUL 05 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at 1255 PM EDT Fri Jul 5 2013
Updated the forecast to decrease PoPs a bit back in the western CWA
along with raising afternoon maximum temperatures slightly. We also
increased PoPs in the east where several rounds of moderate to heavy
showers are currently moving through. The heaviest precipitation
will be across the northern Bluegrass region over the next few hours
then a general decrease in coverage is expected. More showers and
perhaps a thunderstorm or two will be possible later this afternoon
if we can get some clearing.
An early look at the 05/12Z data suite continues to show a high
likelihood more heavy rainfall tonight and again Saturday night.
Given what`s already fallen plus the potential for another 2-4
inches through Sunday night, have opted to extend the Flash Flood
Warning through Sunday morning. We also expanded the watch slightly
on the western side as the latest data suggest that some heavier
rainfall will impact areas mainly along and east of the I-65
corridor.
Update issued at 1005 AM EDT Fri Jul 5 2013
Mostly cloudy conditions were noted across the service area this
morning. Not much change in the overall atmospheric structure was
noted this morning. We`re still in a squeeze game between ridges on
the US coasts, with an upper level low working out of the eastern
Plains. The flow pattern is producing deep fetch of tropical
moisture coming up from the Florida panhandle northward into the
central-eastern sections of the Ohio Valley.
For the remainder of the morning and into the afternoon hours, the
best chances for rainfall look to be along and east of a line from
near Bowling Green northeastward to near Shelbyville. The axis of
heaviest precipitation will probably set up along our SE counties
mainly along a line from Tompkinsville northeastward through
Lawrenceburg. This area of rain looks to move out early this
afternoon with somewhat of a lull in precipitation coverage this
afternoon. There is some data that suggest that we may see some
breaks in the cloud cover. If this occurs, we could tap into the
insolation and generate enough instability for some thunderstorms to
develop. With precipitable water values up above 1.75 inches,
combined with greater than 80% RH in the low-levels, and little
shear, these storms could train over areas which would result in a
continued flood threat. With this in mind, we plan on keeping the
Flash Flood Watch intact at this time.
We will be closely evaluating the new 12Z data suite as it comes in
later this morning and this afternoon. Our concerns focus on a
couple of mid-level waves that look to bring several more rounds of
showers and storms to the region. The first wave looks to roll in
during the overnight hours tonight. More diurnally driven storms
look likely for Saturday afternoon with another upper wave forecast
to come in Saturday night. Each of these waves will have the
ability to produce widespread convection along with the possibility
of thunderstorms which would be producing torrential rains given the
high atmospheric moisture content. The main forecast challenge will
be determining where the actual heavy precipitation axis will set
up. Overall, the models have not been too bad with the placements
thus far, and our current Flash Flood Watch covers the area at
highest risk for flooding. Current thinking is that if the 12Z
models continue to suggest the additional two waves of convection,
an extension of the watch out through Sunday looks very likely.
&&
.SHORT TERM (Today through Saturday)...
Issued at 306 AM EDT Fri Jul 5 2013
Not much change in the atmosphere during the short term, with the
region continuing to be squeezed between an upper trof to the west
and an upper ridge to the east. An impressive plume of deep
moisture will continue to stream from the Gulf of Mexico to the
Saint Lawrence Valley. As a result, widespread clouds and
occasional showers will dominate the short term forecast.
There really isn`t much model or WPC QPF support for flooding rains
today. Showers continue over the eastern third of the CWA early
this morning, as well depicted by the HRRR, with nothing much
upstream. The HRRR shows the current batch of showers exiting the
region early this morning followed by a lull in the action mid-late
morning. Cross-sections suggest we could see a few breaks in the
clouds this afternoon and some regeneration of showers and a few
thunderstorms. Despite the lack of solid model support for heavy
rain today, the fact remains that we still have an extremely juicy
atmosphere and a good set up for training. Any showers/storms that
do develop today will be capable of locally heavy downpours and
places that get hit repeatedly will certainly suffer some water
problems. So, after coordinating with neighboring offices, will go
ahead and keep most of the Flash Flood Watch. Will, however, shave
off the westernmost edge of the watch where rainfall amounts
yesterday were fairly moderate and FFG numbers are higher.
Tonight a coherent vort max is progged to move from south to north
across the area, resulting in widespread showers and maybe a few
thunderstorms, especially after midnight. As of right now, this
activity actually looks slightly more promising for heavy rains than
what we see today, though the main axis should be just slightly west
of where the most rain has fallen over the past 24 hours.
After another lull Saturday morning, additional development is
expected in the afternoon with some destabilization plus the
possibility of another wave moving through. Once again locally
heavy downpours will be possible.
Our high temperatures on the Fourth of July were more typical of
late April. With maybe a little less rain and a bit of partial
sunshine possible this afternoon will go a few degrees warmer than
yesterday for highs today but will still stay well below normal with
highs in the middle and upper 70s. The far west may touch 80. Lows
tonight will be in the middle and upper 60s, with highs on Saturday
not much different from what we see today.
.LONG TERM (Saturday Night through Thursday)...
Issued at 307 AM EDT Fri Jul 5 2013
Unsettled and frequently cloudy weather is expected for the latter
portion of the weekend. For the last several days, a massive Bermuda
high of near 600dm off the Virginia coast has blocked a sharp trough
aligned over the Lower Missouri Valley from moving east. This
pattern will finally break down early next week as zonal flow
becomes established over the northern tier of the country.
However, for Saturday night and for much of Sunday, this practically
cut-off 500mb low will still lie west of Louisville, only slowly
crossing southern Indiana by late Sunday. Through Sunday
afternoon, the Lower Ohio Valley will still lie under a plume of
tropical moisture extending north from the Gulf of Mexico. Expect
cloudy skies Saturday night through early Sunday with occasional
showers and maybe an isolated thunderstorm. Instability will stay
marginal for thunderstorms, but with PWATs just under 2 inches and
some lift associated with a jet overhead, some of these showers
could produce localized heavy rain. Rain chances may actually
diminish a bit towards Sunday evening as veering winds bring drier
air in from the west late in the day. Seasonably cool temperatures
in the lower 80s are expected Sunday afternoon, even with some
potential partial clearing late.
Summer returns Monday and Tuesday. Southwesterly flow will become
established as the aforementioned 500mb low weakens and scoots
across New England. By late Monday, the polar jet will have
retreated to north of the Great Lakes and weak flow aloft will
develop over the region as broad 500mb ridging spreads eastwards
from the southern Plains. Expect a warm humid regime Monday through
Wednesday. Our recent rains will augment already humid air, so each
overnight period will feel muggy. Afternoon high temperatures will
possibly approach 90 for this period.
Afternoon and evening thunderstorms are possible each day, with
coverage likely the least on Monday. PWATs increase again Tuesday
and Wednesday to over 1.75 inches. This may allow individual
thunderstorms to produce localized heavy rains.
A shortwave across the upper Midwest late Wednesday will begin to
dig, eventually carving a trough over western New England by next
Friday. A cold front will approach southern Indiana early Thursday.
Gulf moisture pooling ahead of this boundary will aid in developing
possibly widespread convection late Wednesday into Thursday with the
possibility of localized heavy rainfall. Currently, our forecast has
high chances for Wednesday afternoon and overnight. However, we may
bring in likely chances in later forecasts once the front`s timing
becomes better known.
&&
.AVIATION (18Z TAF Update)...
Issued at 125 PM EDT Fri Jul 5 2013
A deep moisture plume coming in from the Gulf of Mexico combined
with a couple of mid-level disturbances will lead to several rounds
of showers and thunderstorms across the region. The timing and
coverage of these showers and storms makes this a low confidence TAF
forecast to say the least.
For this afternoon, we expect MVFR ceilings to continue through the
afternoon hours. Some improvement to VFR is possible at times, but
with low LCL`s in the area, feel that ceilings are going to be right
around the MVFR/VFR threshold. Scattered showers will be possible
at the terminals with KLEX and KBWG having the best shot at seeing
rainfall. Winds will remain out of the south at 4-7 knots.
The latest model solutions bring in another mid-level disturbance
tonight which should result in more widespread shower and possibly
some embedded thunderstorms. Current thinking is that convection
coverage will increase after 06/04Z and persist through the
remainder of the TAF period. A lull in the activity is possible by
mid-morning Saturday. The heavy rain tonight will probably push
ceilings down to the MVFR/IFR category with mainly MVFR vsbys. IFR
vsbys will be possible in the heavier showers that affect the
terminals.
&&
.HYDROLOGY...
Issued at 1258 PM EDT Fri Jul 5 2013
Current Flash Flood Watch remains in effect for much of central
Kentucky through this evening. Rainfall across the region today may
be not be as widespread as we`ve seen in recent days. However, we
may see more thunderstorm activity this afternoon if breaks in the
clouds develop and tap into the diurnal instability that is forecast
to develop. The current data suite continues to show the potential
for two additional waves of shower and thunderstorm activity. The
first wave is forecast to move in during the overnight hours tonight
and then a secondary wave is very possible Saturday night and into
Sunday morning. These showers and storms will have access to a very
rich airmass with precipitable water values in the 1.8-2.0 inch
range and near complete saturation in the low-levels. This combined
with a low shear profile suggests that low-centroid, highly
efficient rainers with the potential for training. The latest
05/12Z guidance suggests that another 2-4 inches of rainfall will be
possible through Sunday morning as two upper level waves are
forecast to push through the region. Because of this, we have
expanded and extended the Flash Flood Watch through Sunday morning.
We have also been looking at both the deterministic and ensemble QPF
and ensemble river forecast guidance for our larger rivers. At this
time, the data suggests that we may develop flooding problems on the
Green River, the Rolling Fork River, the Kentucky River, and the
Licking River basin through the upcoming weekend. We will be
closely evaluating the new suite of data and will be coordinating
with the OHRFC this afternoon. In looking back at the history books,
the last time we had flooding on the Rolling Fork at Boston, KY in
July was back in 1967. Just goes to show how anomalous this pattern
is for July.
Persons living near creeks, streams, and typical flood prone areas
should keep abreast of water levels and be prepared to take action
if water starts to rise or if warnings are issued.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR KYZ027>029-033>043-
045>049-053>057-061>067-070>078-081-082.
$$
Update...........MJ
Short Term.......13
Long Term........JSD
Aviation.........MJ
Hydrology........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
101 PM EDT FRI JUL 05 2013
.FORECAST UPDATE...
Issued at 1255 PM EDT Fri Jul 5 2013
Updated the forecast to decrease PoPs a bit back in the western CWA
along with raising afternoon maximum temperatures slightly. We also
increased PoPs in the east where several rounds of moderate to heavy
showers are currently moving through. The heaviest precipitation
will be across the northern Bluegrass region over the next few hours
then a general decrease in coverage is expected. More showers and
perhaps a thunderstorm or two will be possible later this afternoon
if we can get some clearing.
An early look at the 05/12Z data suite continues to show a high
likelihood more heavy rainfall tonight and again Saturday night.
Given what`s already fallen plus the potential for another 2-4
inches through Sunday night, have opted to extend the Flash Flood
Warning through Sunday morning. We also expanded the watch slightly
on the western side as the latest data suggest that some heavier
rainfall will impact areas mainly along and east of the I-65
corridor.
Update issued at 1005 AM EDT Fri Jul 5 2013
Mostly cloudy conditions were noted across the service area this
morning. Not much change in the overall atmospheric structure was
noted this morning. We`re still in a squeeze game between ridges on
the US coasts, with an upper level low working out of the eastern
Plains. The flow pattern is producing deep fetch of tropical
moisture coming up from the Florida panhandle northward into the
central-eastern sections of the Ohio Valley.
For the remainder of the morning and into the afternoon hours, the
best chances for rainfall look to be along and east of a line from
near Bowling Green northeastward to near Shelbyville. The axis of
heaviest precipitation will probably set up along our SE counties
mainly along a line from Tompkinsville northeastward through
Lawrenceburg. This area of rain looks to move out early this
afternoon with somewhat of a lull in precipitation coverage this
afternoon. There is some data that suggest that we may see some
breaks in the cloud cover. If this occurs, we could tap into the
insolation and generate enough instability for some thunderstorms to
develop. With precipitable water values up above 1.75 inches,
combined with greater than 80% RH in the low-levels, and little
shear, these storms could train over areas which would result in a
continued flood threat. With this in mind, we plan on keeping the
Flash Flood Watch intact at this time.
We will be closely evaluating the new 12Z data suite as it comes in
later this morning and this afternoon. Our concerns focus on a
couple of mid-level waves that look to bring several more rounds of
showers and storms to the region. The first wave looks to roll in
during the overnight hours tonight. More diurnally driven storms
look likely for Saturday afternoon with another upper wave forecast
to come in Saturday night. Each of these waves will have the
ability to produce widespread convection along with the possibility
of thunderstorms which would be producing torrential rains given the
high atmospheric moisture content. The main forecast challenge will
be determining where the actual heavy precipitation axis will set
up. Overall, the models have not been too bad with the placements
thus far, and our current Flash Flood Watch covers the area at
highest risk for flooding. Current thinking is that if the 12Z
models continue to suggest the additional two waves of convection,
an extension of the watch out through Sunday looks very likely.
&&
.SHORT TERM (Today through Saturday)...
Issued at 306 AM EDT Fri Jul 5 2013
Not much change in the atmosphere during the short term, with the
region continuing to be squeezed between an upper trof to the west
and an upper ridge to the east. An impressive plume of deep
moisture will continue to stream from the Gulf of Mexico to the
Saint Lawrence Valley. As a result, widespread clouds and
occasional showers will dominate the short term forecast.
There really isn`t much model or WPC QPF support for flooding rains
today. Showers continue over the eastern third of the CWA early
this morning, as well depicted by the HRRR, with nothing much
upstream. The HRRR shows the current batch of showers exiting the
region early this morning followed by a lull in the action mid-late
morning. Cross-sections suggest we could see a few breaks in the
clouds this afternoon and some regeneration of showers and a few
thunderstorms. Despite the lack of solid model support for heavy
rain today, the fact remains that we still have an extremely juicy
atmosphere and a good set up for training. Any showers/storms that
do develop today will be capable of locally heavy downpours and
places that get hit repeatedly will certainly suffer some water
problems. So, after coordinating with neighboring offices, will go
ahead and keep most of the Flash Flood Watch. Will, however, shave
off the westernmost edge of the watch where rainfall amounts
yesterday were fairly moderate and FFG numbers are higher.
Tonight a coherent vort max is progged to move from south to north
across the area, resulting in widespread showers and maybe a few
thunderstorms, especially after midnight. As of right now, this
activity actually looks slightly more promising for heavy rains than
what we see today, though the main axis should be just slightly west
of where the most rain has fallen over the past 24 hours.
After another lull Saturday morning, additional development is
expected in the afternoon with some destabilization plus the
possibility of another wave moving through. Once again locally
heavy downpours will be possible.
Our high temperatures on the Fourth of July were more typical of
late April. With maybe a little less rain and a bit of partial
sunshine possible this afternoon will go a few degrees warmer than
yesterday for highs today but will still stay well below normal with
highs in the middle and upper 70s. The far west may touch 80. Lows
tonight will be in the middle and upper 60s, with highs on Saturday
not much different from what we see today.
.LONG TERM (Saturday Night through Thursday)...
Issued at 307 AM EDT Fri Jul 5 2013
Unsettled and frequently cloudy weather is expected for the latter
portion of the weekend. For the last several days, a massive Bermuda
high of near 600dm off the Virginia coast has blocked a sharp trough
aligned over the Lower Missouri Valley from moving east. This
pattern will finally break down early next week as zonal flow
becomes established over the northern tier of the country.
However, for Saturday night and for much of Sunday, this practically
cut-off 500mb low will still lie west of Louisville, only slowly
crossing southern Indiana by late Sunday. Through Sunday
afternoon, the Lower Ohio Valley will still lie under a plume of
tropical moisture extending north from the Gulf of Mexico. Expect
cloudy skies Saturday night through early Sunday with occasional
showers and maybe an isolated thunderstorm. Instability will stay
marginal for thunderstorms, but with PWATs just under 2 inches and
some lift associated with a jet overhead, some of these showers
could produce localized heavy rain. Rain chances may actually
diminish a bit towards Sunday evening as veering winds bring drier
air in from the west late in the day. Seasonably cool temperatures
in the lower 80s are expected Sunday afternoon, even with some
potential partial clearing late.
Summer returns Monday and Tuesday. Southwesterly flow will become
established as the aforementioned 500mb low weakens and scoots
across New England. By late Monday, the polar jet will have
retreated to north of the Great Lakes and weak flow aloft will
develop over the region as broad 500mb ridging spreads eastwards
from the southern Plains. Expect a warm humid regime Monday through
Wednesday. Our recent rains will augment already humid air, so each
overnight period will feel muggy. Afternoon high temperatures will
possibly approach 90 for this period.
Afternoon and evening thunderstorms are possible each day, with
coverage likely the least on Monday. PWATs increase again Tuesday
and Wednesday to over 1.75 inches. This may allow individual
thunderstorms to produce localized heavy rains.
A shortwave across the upper Midwest late Wednesday will begin to
dig, eventually carving a trough over western New England by next
Friday. A cold front will approach southern Indiana early Thursday.
Gulf moisture pooling ahead of this boundary will aid in developing
possibly widespread convection late Wednesday into Thursday with the
possibility of localized heavy rainfall. Currently, our forecast has
high chances for Wednesday afternoon and overnight. However, we may
bring in likely chances in later forecasts once the front`s timing
becomes better known.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Fri Jul 5 2013
The deep moisture plume coming from the Gulf of Mexico will continue
through today and tonight, leading to a very moist atmosphere and a
low confidence TAF package.
Low ceilings are the primary concern this morning. Ceilings around
the MVFR/IFR border have been coming and going. It is currently
felt that these ceilings will likely prevail early this morning.
Will then gradually allow those ceilings to lift, reaching low VFR
this afternoon.
Showers will be possible just about any time through the TAF
period. LEX will stand the best chance of the most consistent
rain. A few thunderstorms will be possible as well, primarily this
afternoon. The best chances tonight appear to be during the
overnight hours as a weak upper wave moves through.
&&
.HYDROLOGY...
Issued at 1258 PM EDT Fri Jul 5 2013
Current Flash Flood Watch remains in effect for much of central
Kentucky through this evening. Rainfall across the region today may
be not be as widespread as we`ve seen in recent days. However, we
may see more thunderstorm activity this afternoon if breaks in the
clouds develop and tap into the diurnal instability that is forecast
to develop. The current data suite continues to show the potential
for two additional waves of shower and thunderstorm activity. The
first wave is forecast to move in during the overnight hours tonight
and then a secondary wave is very possible Saturday night and into
Sunday morning. These showers and storms will have access to a very
rich airmass with precipitable water values in the 1.8-2.0 inch
range and near complete saturation in the low-levels. This combined
with a low shear profile suggests that low-centroid, highly
efficient rainers with the potential for training. The latest
05/12Z guidance suggests that another 2-4 inches of rainfall will be
possible through Sunday morning as two upper level waves are
forecast to push through the region. Because of this, we have
expanded and extended the Flash Flood Watch through Sunday morning.
We have also been looking at both the deterministic and ensemble QPF
and ensemble river forecast guidance for our larger rivers. At this
time, the data suggests that we may develop flooding problems on the
Green River, the Rolling Fork River, the Kentucky River, and the
Licking River basin through the upcoming weekend. We will be
closely evaluating the new suite of data and will be coordinating
with the OHRFC this afternoon. In looking back at the history books,
the last time we had flooding on the Rolling Fork at Boston, KY in
July was back in 1967. Just goes to show how anomalous this pattern
is for July.
Persons living near creeks, streams, and typical flood prone areas
should keep abreast of water levels and be prepared to take action
if water starts to rise or if warnings are issued.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR KYZ027>029-033>043-
045>049-053>057-061>067-070>078-081-082.
$$
Update...........MJ
Short Term.......13
Long Term........JSD
Aviation.........13
Hydrology........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1011 AM EDT FRI JUL 05 2013
.FORECAST UPDATE...
Issued at 1005 AM EDT Fri Jul 5 2013
Mostly cloudy conditions were noted across the service area this
morning. Not much change in the overall atmospheric structure was
noted this morning. We`re still in a squeeze game between ridges on
the US coasts, with an upper level low working out of the eastern
Plains. The flow pattern is producing deep fetch of tropical
moisture coming up from the Florida panhandle northward into the
central-eastern sections of the Ohio Valley.
For the remainder of the morning and into the afternoon hours, the
best chances for rainfall look to be along and east of a line from
near Bowling Green northeastward to near Shelbyville. The axis of
heaviest precipitation will probably set up along our SE counties
mainly along a line from Tompkinsville northeastward through
Lawrenceburg. This area of rain looks to move out early this
afternoon with somewhat of a lull in precipitation coverage this
afternoon. There is some data that suggest that we may see some
breaks in the cloud cover. If this occurs, we could tap into the
insolation and generate enough instability for some thunderstorms to
develop. With precipitable water values up above 1.75 inches,
combined with greater than 80% RH in the low-levels, and little
shear, these storms could train over areas which would result in a
continued flood threat. With this in mind, we plan on keeping the
Flash Flood Watch intact at this time.
We will be closely evaluating the new 12Z data suite as it comes in
later this morning and this afternoon. Our concerns focus on a
couple of mid-level waves that look to bring several more rounds of
showers and storms to the region. The first wave looks to roll in
during the overnight hours tonight. More diurnally driven storms
look likely for Saturday afternoon with another upper wave forecast
to come in Saturday night. Each of these waves will have the
ability to produce widespread convection along with the possibility
of thunderstorms which would be producing torrential rains given the
high atmospheric moisture content. The main forecast challenge will
be determining where the actual heavy precipitation axis will set
up. Overall, the models have not been too bad with the placements
thus far, and our current Flash Flood Watch covers the area at
highest risk for flooding. Current thinking is that if the 12Z
models continue to suggest the additional two waves of convection,
an extension of the watch out through Sunday looks very likely.
&&
.SHORT TERM (Today through Saturday)...
Issued at 306 AM EDT Fri Jul 5 2013
Not much change in the atmosphere during the short term, with the
region continuing to be squeezed between an upper trof to the west
and an upper ridge to the east. An impressive plume of deep
moisture will continue to stream from the Gulf of Mexico to the
Saint Lawrence Valley. As a result, widespread clouds and
occasional showers will dominate the short term forecast.
There really isn`t much model or WPC QPF support for flooding rains
today. Showers continue over the eastern third of the CWA early
this morning, as well depicted by the HRRR, with nothing much
upstream. The HRRR shows the current batch of showers exiting the
region early this morning followed by a lull in the action mid-late
morning. Cross-sections suggest we could see a few breaks in the
clouds this afternoon and some regeneration of showers and a few
thunderstorms. Despite the lack of solid model support for heavy
rain today, the fact remains that we still have an extremely juicy
atmosphere and a good set up for training. Any showers/storms that
do develop today will be capable of locally heavy downpours and
places that get hit repeatedly will certainly suffer some water
problems. So, after coordinating with neighboring offices, will go
ahead and keep most of the Flash Flood Watch. Will, however, shave
off the westernmost edge of the watch where rainfall amounts
yesterday were fairly moderate and FFG numbers are higher.
Tonight a coherent vort max is progged to move from south to north
across the area, resulting in widespread showers and maybe a few
thunderstorms, especially after midnight. As of right now, this
activity actually looks slightly more promising for heavy rains than
what we see today, though the main axis should be just slightly west
of where the most rain has fallen over the past 24 hours.
After another lull Saturday morning, additional development is
expected in the afternoon with some destabilization plus the
possibility of another wave moving through. Once again locally
heavy downpours will be possible.
Our high temperatures on the Fourth of July were more typical of
late April. With maybe a little less rain and a bit of partial
sunshine possible this afternoon will go a few degrees warmer than
yesterday for highs today but will still stay well below normal with
highs in the middle and upper 70s. The far west may touch 80. Lows
tonight will be in the middle and upper 60s, with highs on Saturday
not much different from what we see today.
.LONG TERM (Saturday Night through Thursday)...
Issued at 307 AM EDT Fri Jul 5 2013
Unsettled and frequently cloudy weather is expected for the latter
portion of the weekend. For the last several days, a massive Bermuda
high of near 600dm off the Virginia coast has blocked a sharp trough
aligned over the Lower Missouri Valley from moving east. This
pattern will finally break down early next week as zonal flow
becomes established over the northern tier of the country.
However, for Saturday night and for much of Sunday, this practically
cut-off 500mb low will still lie west of Louisville, only slowly
crossing southern Indiana by late Sunday. Through Sunday
afternoon, the Lower Ohio Valley will still lie under a plume of
tropical moisture extending north from the Gulf of Mexico. Expect
cloudy skies Saturday night through early Sunday with occasional
showers and maybe an isolated thunderstorm. Instability will stay
marginal for thunderstorms, but with PWATs just under 2 inches and
some lift associated with a jet overhead, some of these showers
could produce localized heavy rain. Rain chances may actually
diminish a bit towards Sunday evening as veering winds bring drier
air in from the west late in the day. Seasonably cool temperatures
in the lower 80s are expected Sunday afternoon, even with some
potential partial clearing late.
Summer returns Monday and Tuesday. Southwesterly flow will become
established as the aforementioned 500mb low weakens and scoots
across New England. By late Monday, the polar jet will have
retreated to north of the Great Lakes and weak flow aloft will
develop over the region as broad 500mb ridging spreads eastwards
from the southern Plains. Expect a warm humid regime Monday through
Wednesday. Our recent rains will augment already humid air, so each
overnight period will feel muggy. Afternoon high temperatures will
possibly approach 90 for this period.
Afternoon and evening thunderstorms are possible each day, with
coverage likely the least on Monday. PWATs increase again Tuesday
and Wednesday to over 1.75 inches. This may allow individual
thunderstorms to produce localized heavy rains.
A shortwave across the upper Midwest late Wednesday will begin to
dig, eventually carving a trough over western New England by next
Friday. A cold front will approach southern Indiana early Thursday.
Gulf moisture pooling ahead of this boundary will aid in developing
possibly widespread convection late Wednesday into Thursday with the
possibility of localized heavy rainfall. Currently, our forecast has
high chances for Wednesday afternoon and overnight. However, we may
bring in likely chances in later forecasts once the front`s timing
becomes better known.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Fri Jul 5 2013
The deep moisture plume coming from the Gulf of Mexico will continue
through today and tonight, leading to a very moist atmosphere and a
low confidence TAF package.
Low ceilings are the primary concern this morning. Ceilings around
the MVFR/IFR border have been coming and going. It is currently
felt that these ceilings will likely prevail early this morning.
Will then gradually allow those ceilings to lift, reaching low VFR
this afternoon.
Showers will be possible just about any time through the TAF
period. LEX will stand the best chance of the most consistent
rain. A few thunderstorms will be possible as well, primarily this
afternoon. The best chances tonight appear to be during the
overnight hours as a weak upper wave moves through.
&&
.HYDROLOGY...
Issued at 1010 AM EDT Fri Jul 5 2013
Current Flash Flood Watch remains in effect for much of central
Kentucky through this evening. Rainfall across the region today may
be not be as widespread as we`ve seen in recent days. However, we
may see more thunderstorm activity this afternoon if breaks in the
clouds develop and tap into the diurnal instability that is forecast
to develop. The current data suite continues to show the potential
for two additional waves of shower and thunderstorm activity. The
first wave is forecast to move in during the overnight hours tonight
and then a secondary wave is very possible Saturday night and into
Sunday morning. These showers and storms will have access to a very
rich airmass with precipitable water values in the 1.8-2.0 inch
range and near complete saturation in the low-levels. This combined
with a low shear profile suggests that low-centroid, highly
efficient rainers with the potential for training. If the new
05/12Z data suite supports this, the Flash Flood Watch will need to
be extended in time through at least Sunday Morning.
We have also been looking at both the deterministic and ensemble QPF
and ensemble river forecast guidance for our larger rivers. At this
time, the data suggests that we may develop flooding problems on the
Green River, the Rolling Fork River, the Kentucky River, and the
Licking River basin through the upcoming weekend. We will be
closely evaluating the new suite of data and will be coordinating
with the OHRFC this afternoon.
Persons living near creeks, streams, and typical flood prone areas
should keep abreast of water levels and be prepared to take action
if water starts to rise or if warnings are issued.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLASH FLOOD WATCH UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR
KYZ033>043-045>049-053>057-063>067-073>078-081-082.
$$
Update...........MJ
Short Term.......13
Long Term........JSD
Aviation.........13
Hydrology........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
645 AM EDT FRI JUL 05 2013
...Updated Aviation Discussion...
.SHORT TERM (Today through Saturday)...
Issued at 306 AM EDT Fri Jul 5 2013
Not much change in the atmosphere during the short term, with the
region continuing to be squeezed between an upper trof to the west
and an upper ridge to the east. An impressive plume of deep
moisture will continue to stream from the Gulf of Mexico to the
Saint Lawrence Valley. As a result, widespread clouds and
occasional showers will dominate the short term forecast.
There really isn`t much model or WPC QPF support for flooding rains
today. Showers continue over the eastern third of the CWA early
this morning, as well depicted by the HRRR, with nothing much
upstream. The HRRR shows the current batch of showers exiting the
region early this morning followed by a lull in the action mid-late
morning. Cross-sections suggest we could see a few breaks in the
clouds this afternoon and some regeneration of showers and a few
thunderstorms. Despite the lack of solid model support for heavy
rain today, the fact remains that we still have an extremely juicy
atmosphere and a good set up for training. Any showers/storms that
do develop today will be capable of locally heavy downpours and
places that get hit repeatedly will certainly suffer some water
problems. So, after coordinating with neighboring offices, will go
ahead and keep most of the Flash Flood Watch. Will, however, shave
off the westernmost edge of the watch where rainfall amounts
yesterday were fairly moderate and FFG numbers are higher.
Tonight a coherent vort max is progged to move from south to north
across the area, resulting in widespread showers and maybe a few
thunderstorms, especially after midnight. As of right now, this
activity actually looks slightly more promising for heavy rains than
what we see today, though the main axis should be just slightly west
of where the most rain has fallen over the past 24 hours.
After another lull Saturday morning, additional development is
expected in the afternoon with some destabilization plus the
possibility of another wave moving through. Once again locally
heavy downpours will be possible.
Our high temperatures on the Fourth of July were more typical of
late April. With maybe a little less rain and a bit of partial
sunshine possible this afternoon will go a few degrees warmer than
yesterday for highs today but will still stay well below normal with
highs in the middle and upper 70s. The far west may touch 80. Lows
tonight will be in the middle and upper 60s, with highs on Saturday
not much different from what we see today.
.LONG TERM (Saturday Night through Thursday)...
Issued at 307 AM EDT Fri Jul 5 2013
Unsettled and frequently cloudy weather is expected for the latter
portion of the weekend. For the last several days, a massive Bermuda
high of near 600dm off the Virginia coast has blocked a sharp trough
aligned over the Lower Missouri Valley from moving east. This
pattern will finally break down early next week as zonal flow
becomes established over the northern tier of the country.
However, for Saturday night and for much of Sunday, this practically
cut-off 500mb low will still lie west of Louisville, only slowly
crossing southern Indiana by late Sunday. Through Sunday
afternoon, the Lower Ohio Valley will still lie under a plume of
tropical moisture extending north from the Gulf of Mexico. Expect
cloudy skies Saturday night through early Sunday with occasional
showers and maybe an isolated thunderstorm. Instability will stay
marginal for thunderstorms, but with PWATs just under 2 inches and
some lift associated with a jet overhead, some of these showers
could produce localized heavy rain. Rain chances may actually
diminish a bit towards Sunday evening as veering winds bring drier
air in from the west late in the day. Seasonably cool temperatures
in the lower 80s are expected Sunday afternoon, even with some
potential partial clearing late.
Summer returns Monday and Tuesday. Southwesterly flow will become
established as the aforementioned 500mb low weakens and scoots
across New England. By late Monday, the polar jet will have
retreated to north of the Great Lakes and weak flow aloft will
develop over the region as broad 500mb ridging spreads eastwards
from the southern Plains. Expect a warm humid regime Monday through
Wednesday. Our recent rains will augment already humid air, so each
overnight period will feel muggy. Afternoon high temperatures will
possibly approach 90 for this period.
Afternoon and evening thunderstorms are possible each day, with
coverage likely the least on Monday. PWATs increase again Tuesday
and Wednesday to over 1.75 inches. This may allow individual
thunderstorms to produce localized heavy rains.
A shortwave across the upper Midwest late Wednesday will begin to
dig, eventually carving a trough over western New England by next
Friday. A cold front will approach southern Indiana early Thursday.
Gulf moisture pooling ahead of this boundary will aid in developing
possibly widespread convection late Wednesday into Thursday with the
possibility of localized heavy rainfall. Currently, our forecast has
high chances for Wednesday afternoon and overnight. However, we may
bring in likely chances in later forecasts once the front`s timing
becomes better known.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Fri Jul 5 2013
The deep moisture plume coming from the Gulf of Mexico will continue
through today and tonight, leading to a very moist atmosphere and a
low confidence TAF package.
Low ceilings are the primary concern this morning. Ceilings around
the MVFR/IFR border have been coming and going. It is currently
felt that these ceilings will likely prevail early this morning.
Will then gradually allow those ceilings to lift, reaching low VFR
this afternoon.
Showers will be possible just about any time through the TAF
period. LEX will stand the best chance of the most consistent
rain. A few thunderstorms will be possible as well, primarily this
afternoon. The best chances tonight appear to be during the
overnight hours as a weak upper wave moves through.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLASH FLOOD WATCH THROUGH THIS EVENING FOR KYZ033>043-045>049-
053>057-063>067-073>078-081-082.
$$
Short Term.......13
Long Term........JSD
Aviation.........13
AREA FORECAST DISCUSSION...COR TO INIT
NWS LOUISVILLE KY
308 AM EDT FRI JUL 05 2013
.SHORT TERM (Today through Saturday)...
Issued at 306 AM EDT Fri Jul 5 2013
Not much change in the atmosphere during the short term, with the
region continuing to be squeezed between an upper trof to the west
and an upper ridge to the east. An impressive plume of deep
moisture will continue to stream from the Gulf of Mexico to the
Saint Lawrence Valley. As a result, widespread clouds and
occasional showers will dominate the short term forecast.
There really isn`t much model or WPC QPF support for flooding rains
today. Showers continue over the eastern third of the CWA early
this morning, as well depicted by the HRRR, with nothing much
upstream. The HRRR shows the current batch of showers exiting the
region early this morning followed by a lull in the action mid-late
morning. Cross-sections suggest we could see a few breaks in the
clouds this afternoon and some regeneration of showers and a few
thunderstorms. Despite the lack of solid model support for heavy
rain today, the fact remains that we still have an extremely juicy
atmosphere and a good set up for training. Any showers/storms that
do develop today will be capable of locally heavy downpours and
places that get hit repeatedly will certainly suffer some water
problems. So, after coordinating with neighboring offices, will go
ahead and keep most of the Flash Flood Watch. Will, however, shave
off the westernmost edge of the watch where rainfall amounts
yesterday were fairly moderate and FFG numbers are higher.
Tonight a coherent vort max is progged to move from south to north
across the area, resulting in widespread showers and maybe a few
thunderstorms, especially after midnight. As of right now, this
activity actually looks slightly more promising for heavy rains than
what we see today, though the main axis should be just slightly west
of where the most rain has fallen over the past 24 hours.
After another lull Saturday morning, additional development is
expected in the afternoon with some destabilization plus the
possibility of another wave moving through. Once again locally
heavy downpours will be possible.
Our high temperatures on the Fourth of July were more typical of
late April. With maybe a little less rain and a bit of partial
sunshine possible this afternoon will go a few degrees warmer than
yesterday for highs today but will still stay well below normal with
highs in the middle and upper 70s. The far west may touch 80. Lows
tonight will be in the middle and upper 60s, with highs on Saturday
not much different from what we see today.
.LONG TERM (Saturday Night through Thursday)...
Issued at 307 AM EDT Fri Jul 5 2013
Unsettled and frequently cloudy weather is expected for the latter
portion of the weekend. For the last several days, a massive Bermuda
high of near 600dm off the Virginia coast has blocked a sharp trough
aligned over the Lower Missouri Valley from moving east. This pattern
will finally break down early next week as zonal flow becomes
established over the northern tier of the country.
However, for Saturday night and for much of Sunday, this practically
cut-off 500mb low will still lie west of Louisville, only slowly
crossing southern Indiana by late Sunday. Through Sunday
afternoon, the Lower Ohio Valley will still lie under a plume of
tropical moisture extending north from the Gulf of Mexico. Expect
cloudy skies Saturday night through early Sunday with occasional
showers and maybe an isolated thunderstorm. Instability will stay
marginal for thunderstorms, but with PWATs just under 2 inches and
some lift associated with a jet overhead, some of these showers
could produce localized heavy rain. Rain chances may actually
diminish a bit towards Sunday evening as veering winds bring drier
air in from the west late in the day. Seasonably cool temperatures
in the lower 80s are expected Sunday afternoon, even with some
potential partial clearing late.
Summer returns Monday and Tuesday. Southwesterly flow will become
established as the aforementioned 500mb low weakens and scoots
across New England. By late Monday, the polar jet will have
retreated to north of the Great Lakes and weak flow aloft will
develop over the region as broad 500mb ridging spreads eastwards
from the southern Plains. Expect a warm humid regime Monday through
Wednesday. Our recent rains will augment already humid air, so each
overnight period will feel muggy. Afternoon high temperatures will
possibly approach 90 for this period.
Afternoon and evening thunderstorms are possible each day, with
coverage likely the least on Monday. PWATs increase again Tuesday
and Wednesday to over 1.75 inches. This may allow individual
thunderstorms to produce localized heavy rains.
A shortwave across the upper Midwest late Wednesday will begin to
dig, eventually carving a trough over western New England by next
Friday. A cold front will approach southern Indiana early Thursday.
Gulf moisture pooling ahead of this boundary will aid in developing
possibly widespread convection late Wednesday into Thursday with the
possibility of localized heavy rainfall. Currently, our forecast has
high chances for Wednesday afternoon and overnight. However, we may
bring in likely chances in later forecasts once the front`s timing
becomes better known.
&&
.AVIATION (06Z TAF Update)...
Issued at 101 AM EDT Fri Jul 5 2013
The deep moisture plume coming from the Gulf of Mexico will continue
through today and tonight, leading to a very moist atmosphere and a
low confidence TAF package.
Low ceilings are the primary concern this morning. Model data are
fairly insistent bringing in ceilings around the MVFR/IFR border,
and indeed some transient ceilings a few hundred feet either side of
1000` have already developed from western Kentucky to middle
Tennessee. So, will go ahead and continue with low cigs in the
forecast from the pre-dawn hours through mid morning. Will then
gradually allow those ceilings to lift, reaching low VFR this
afternoon.
Showers will be possible just about any time through the TAF
period. LEX will stand the best chance of the most consistent
rain. A few thunderstorms will be possible as well, primarily this
afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH THROUGH THIS EVENING FOR INZ079-092.
KY...FLASH FLOOD WATCH THROUGH THIS EVENING FOR KYZ027>043-045>049-
053>057-061>067-070>078-081-082.
$$
Short Term.......13
Long Term........JSD
Aviation.........13
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EDT FRI JUL 5 2013
THE UPPER TROUGH THAT HAS BEEN INFLUENCING OUR WEATHER OVER THE
LAST SEVERAL DAYS HAS CONTINUED TO WEAKEN AND IS NOW NEARLY CUTOFF
FROM THE MAIN WEST-EAST FLOW ACROSS SOUTHERN CANADA. A SHORTWAVE
CURRENTLY MOVING INTO SOUTHWEST ONTARIO AND NORTHWEST MINNESOTA
WILL SHEAR OUT AND SLIDE NORTH OF THE AREA TODAY AND TONIGHT. AT THE
SURFACE...AREA IS UNDER A RIDGE FROM A HIGH CENTERED IN THE WESTERN
ATLANTIC. THIS LED TO INCREASING SOUTHWESTERLY FLOW YESTERDAY AND
IT WILL CONTINUE TODAY AS THE PRESSURE GRADIENT INCREASES DUE TO A
STATIONARY TROUGH SETUP IN WESTERN ONTARIO TO WEST CENTRAL
MINNESOTA. THIS SOUTHWESTERLY FLOW WILL PULL THE DRY AIR SEEN ON
THE 00Z KMPX SOUNDING OVER THE AREA TODAY AND WILL LEAD TO A NICE
AND WARM SUMMER DAY. MIXING TO 850MB TEMPS OF 17C OVER THE WESTERN
CWA AND 15C OVER THE EAST WILL PRODUCE TEMPERATURES IN THE UPPER 80S
OVER THE WEST AND THE MID 80S OVER THE EAST. THE COOLEST VALUES WILL
BE DOWNWIND OF LAKE MICHIGAN UNDER THE SOUTHWESTERLY FLOW. WILL
CONTINUE THE IDEA OF THE PREVIOUS SHIFT WITH A FEW 90 DEGREE VALUES
IN THE FAVORED DOWNSLOPE AREAS OVER THE WEST AND THE TRADITIONAL
WARM RAWS SITES. THESE VALUES ARE FAIRLY SIMILAR SEEN UPSTREAM IN
CENTRAL MINNESOTA YESTERDAY.
NAM/HRRR/RAP SHOWING SOME CU DEVELOPMENT DURING THE AFTERNOON OVER
THE CENTRAL AND EAST. THE HRRR AND ONE OF OUR LOCAL RAP
INITIALIZED WRF-ARW RUNS EVEN DEVELOP A FEW SHOWERS AROUND MID
AFTERNOON OVER EASTERN ALGER AND NORTHERN LUCE COUNTY ALONG THE LAKE
MICHIGAN BREEZE BOUNDARY. WITH ALL OF THE OTHER MODELS SHOWING
SIGNIFICANT DRY AIR ABOVE THAT CU...WILL KEEP OUT OF THE FORECAST
FOR NOW...BUT IT WILL BE SOMETHING FOR THE DAY SHIFT TO KEEP AN EYE
ON. OTHERWISE...WOULD EXPECT MOSTLY SUNNY CONDITIONS ACROSS THE REST
OF THE AREA. THIS WILL AID MIXING INTO THE DRIER AIR ALOFT AND ALSO
MIX DOWN SOME OF THE STRONGER WINDS. HIGHEST CORE OF WINDS WILL BE
OVER THE WESTERN CWA...WHERE GUSTS WILL BE IN THE 20-25KT RANGE. AS
FOR DEWPOINTS...ML VALUES FROM THE MODELS ARE IN THE LOWER 50S AND
WILL FOLLOW THAT IDEA (MATCHES VALUES SEEN UPSTREAM YESTERDAY). THIS
PRODUCES MINIMUM RH VALUES IN THE LOWER 30S OVER THE WEST AND
UPPER 30S OVER THE EAST. ALL OF THESE CONDITIONS...COMBINED WITH A
HOLIDAY WEEKEND AND DRY CONDITIONS OVER THE LAST 5-6 DAYS...SUPPORTS
ISSUING A WILDFIRE POTENTIAL STATEMENT OVER THE WEST HALF EVEN
THOUGH THEY HAVE HAD ABOVE NORMAL PRECIPITATION OVER THE LAST 30
DAYS. SINCE COORDINATION WAS PERFORMED YESTERDAY WITH THE DNR...WILL
GO AHEAD AND ISSUE IT THIS MORNING.
AS FOR CONDITIONS UPSTREAM THAT WILL INFLUENCE TONIGHT/S
FORECAST...THE TROUGH OVER WESTERN MINNESOTA WILL KICK OFF
SHOWERS/THUNDERSTORMS IN NORTH CENTRAL AND NORTHEAST MN THIS
AFTERNOON AND EVENING. WITH LIMITED WESTWARD PUSH TO THE SURFACE
TROUGH TODAY AND STORM MOTIONS PARALLEL TO THE WESTERN LAKE SUPERIOR
SHORELINE...WOULDN/T EXPECT MUCH MOVEMENT OF THE
SHOWERS/THUNDERSTORMS INTO WESTERN LAKE SUPERIOR UNTIL THE EVENING
AND MORE LIKELY OVERNIGHT HOURS AS THE SHORTWAVE GIVES IT A PUSH TO
THE EAST. A COUPLE MODELS HINT AT DEVELOPMENT IN NW WISCONSIN THIS
AFTERNOON WHICH WOULD MOVE NE INTO WESTERN LAKE SUPERIOR...SO WILL
MENTION SLIGHT CHANCES WEST OF THE APOSTLE ISLANDS. WITH NO
SIGNIFICANT UPPER FORCING (LARGELY BROAD AND WEAK OVER WESTERN LAKE
SUPERIOR WITH THE BEST IN ONTARIO) AND JUST THE WEAK SURFACE TROUGH
MOVING INTO WESTERN LAKE SUPERIOR...THINK THE OVERALL POTENTIAL FOR
PRECIPITATION IS LOW TONIGHT. THEREFORE...WILL SLOWLY PUSH THE
SLIGHT CHANCE AND CHANCES POPS EAST ACROSS THE WESTERN LAKE WITH
SLIGHT CHANCE VALUES REACHING THE WESTERN THIRD OF THE U.P. DURING
THE OVERNIGHT HOURS. THIS WILL BE DUE TO THE DIMINISHING
SHOWERS/THUNDERSTORMS EXITING NORTHERN MINNESOTA. OVER THE REST OF
THE AREA...WOULD EXPECT MID CLOUDS TO PUSH EAST-NORTHEAST INTO THE
WEST HALF BY DAYBREAK AND THE EAST WILL STAY MOSTLY CLEAR. WITH THE
PRESSURE GRADIENT KEEPING WINDS UP DURING THE NIGHT...THINK LOWS
WILL STAY IN THE LOW 60S EAST AND MID-UPPER 60S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 458 AM EDT FRI JUL 5 2013
SATURDAY...A MAINLY ZONAL MID/UPPER LEVEL PATTERN IS EXPECTED
ACROSS THE NRN CONUS WHILE A CUTOFF LOW DRIFTS FROM THE MID MS
VALLEY TOWARD IN/OH. AT THE SFC...HIGH PRES BUILDING INTO NRN
ONTARIO WILL PUSH A FRONT TOWARD LAKE SUPERIOR. TEMPERATURES
CLIMBING INTO THE MID 80S WITH DEWPOINTS IN THE LOWER 60S WILL
RESULT IN MLCAPE VALUES TO AROUND 1K J/KG OVER THE CNTRL AND WEST.
SINCE THE FORCING WITH ANY WEAK SHORTWAVES WILL REMAIN NORTH OF THE
THE AREA IN THE STRONGER MID LEVEL FLOW...ONLY LOWER END POPS WERE
INCLUDED OVER THE NW HALF.
SAT NIGHT INTO SUN NIGHT...THE MODELS SUGGEST THAT A STRONGER SHORTWAVE
TROUGH WILL MOVE OUT OF THE PLAINS INTO THE NRN GREAT LAKES. THE
COMBINATION OF FORCING WITH THE SHRTWV AND INCREASING LOW LEVEL
THETA-E ADVECTION PUSHING MUCAPE VALUES INTO THE 1000-1500 J/KG
RANGE WILL SUPPORT INCREASING POPS FROM LATE SATURDAY NIGHT INTO
SUNDAY MORNING. HOWEVER...WITH THE ZONAL PATTERN CONFIDENCE IN THE
POSITION/STRENGTH OF THE THE SHRTWV IS LOW. PWAT VALUES TO AROUND
1.75 INCH WILL BRING POTENTIAL FOR SOME LCLY HEAVY RAIN AS THE MAIN
HAZARD...ESPECIALLY OVER THE WRN CWA. IF ENOUGH BREAKS IN THE CLOUD
COVER DEVELOP...AFTERNOON MLCAPE VALUES COULD CLIMB TO AROUND 1K J/KG
SUPPORTING ANOTHER ROUND OF SCT SHRA/TSRA WITH THE FRONT AND LAKE
BREEZE BOUNDARIES OVER THE AREA. HOWEVER...SHEAR VALUES WILL BE
WEAK/MARGINAL TO SUPPORT ORGANIZED STRONGER/SVR STORMS.
MON...ALTHOUGH THE WEAKENING FRONTAL BOUNDAY S EXPECTED TO SAG TO
THE SOUTH OF UPPER MI...THE POTENTIAL REMAINS FOR WEAK SHRTWVS TO
MOVE THROUGH THE AREA THAT COULD RESULT IN ADDITIONAL PCPN KEEPING
SLIGHT CHANCE POPS GOING OVER MAINLY THE CENTRAL AND EAST.
TUE-THU...THE ECMWF/GFS/GEM HAVE COME INTO BETTER AGREEMENT WITH THE
STRONGER SHORTWAVE TROUGH MOVING INTO THE NRN GREAT LAKES BY WED.
QVECTOR CONV AND MOISTURE ADVECTION AHEAD OF THIS FEATURE WILL
SUPPORT INCREASING SHRA/TSRA CHANCES MAINLY FROM TUE NIGHT INTO
EARLY WED. A RETURN TO COOLER CONDITIONS WITH TEMPS BLO NORMAL ARE
EXPECTED BY THU WITH ONLY A CHANCE OF SOME LINGERING LIGHT
SHOWERS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 141 PM EDT FRI JUL 5 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. AN INCREASING
PRESSURE GRADIENT OVER UPPER MICHIGAN TODAY WILL LEAD TO GUSTY WINDS
THROUGH THE AFTERNOON. WINDS WILL DIMINISH SLIGHTLY AT ALL SITES
THIS EVENING...THOUGH INCREASING WINDS ALOFT WILL RESULT IN MARGINAL
WIND SPEED SHEAR FOR IWD AND CMX OVERNIGHT. AN APPROACHING COLD
FRONT WILL THEN SLOWLY SPREAD CLOUDS AND SHOWERS WEST TO EAST TOWARD
IWD AND CMX BEGINNING LATE TONIGHT. THE BEST CHANCE FOR SHOWERS WILL
BE AT THE END OF THE PERIOD. FOR SAW...ANY SHOWERS SHOULD HOLD OFF
UNTIL SATURDAY AFTERNOON. FOR ALL SITES...ANY SHOWERS THAT FORM
COULD CONTAIN SOME LIGHTNING TOWARD THE AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 458 AM EDT FRI JUL 5 2013
A STRENGTHENING PRESSURE GRADIENT BETWEEN A HIGH IN THE WESTERN
ATLANTIC AND A SLOWLY APPROACHING LOW PRESSURE TROUGH OVER
SOUTH-CENTRAL CANADA WILL ALLOW FOR S-SW WINDS TO CONTINUE THROUGH
SATURDAY. WITH MUCH WARMER TEMPERATURES EXPECTED...THE MARINE LAYER
SHOULD BE QUITE SHALLOW ACROSS SOUTHERN LAKE SUPERIOR...SO GUSTS UP
TO 25 KNOTS COULD BE POSSIBLE ALMOST DOWN TO THE WATER. ACROSS
NORTHERN LAKE SUPERIOR...STRONGER WINDS SHOULD ONLY AFFECT THE
HIGHER PLATFORMS. DRIER AIR SHOULD KEEP THE FOG AT BAY
TODAY...BUT WITH SHOWERS AND THUNDERSTORMS POSSIBLE OVER THE
LAKE LATE TONIGHT THROUGH SUNDAY NIGHT THERE IS THE POTENTIAL
FOR FOG TO DEVELOP. BY SUNDAY NIGHT...WEAK LOW PRESSURE WILL
TRACK EASTWARD ACROSS LAKE SUPERIOR AND BRING LIGHT WINDS UNDER 15
KNOTS. HIGH PRESSURE WILL THEN BUILD IN BEHIND THIS LOW AND KEEP
WINDS LIGHT THROUGH THE BEGINNING OF NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...KLUBER
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EDT FRI JUL 5 2013
THE UPPER TROUGH THAT HAS BEEN INFLUENCING OUR WEATHER OVER THE
LAST SEVERAL DAYS HAS CONTINUED TO WEAKEN AND IS NOW NEARLY CUTOFF
FROM THE MAIN WEST-EAST FLOW ACROSS SOUTHERN CANADA. A SHORTWAVE
CURRENTLY MOVING INTO SOUTHWEST ONTARIO AND NORTHWEST MINNESOTA
WILL SHEAR OUT AND SLIDE NORTH OF THE AREA TODAY AND TONIGHT. AT THE
SURFACE...AREA IS UNDER A RIDGE FROM A HIGH CENTERED IN THE WESTERN
ATLANTIC. THIS LED TO INCREASING SOUTHWESTERLY FLOW YESTERDAY AND
IT WILL CONTINUE TODAY AS THE PRESSURE GRADIENT INCREASES DUE TO A
STATIONARY TROUGH SETUP IN WESTERN ONTARIO TO WEST CENTRAL
MINNESOTA. THIS SOUTHWESTERLY FLOW WILL PULL THE DRY AIR SEEN ON
THE 00Z KMPX SOUNDING OVER THE AREA TODAY AND WILL LEAD TO A NICE
AND WARM SUMMER DAY. MIXING TO 850MB TEMPS OF 17C OVER THE WESTERN
CWA AND 15C OVER THE EAST WILL PRODUCE TEMPERATURES IN THE UPPER 80S
OVER THE WEST AND THE MID 80S OVER THE EAST. THE COOLEST VALUES WILL
BE DOWNWIND OF LAKE MICHIGAN UNDER THE SOUTHWESTERLY FLOW. WILL
CONTINUE THE IDEA OF THE PREVIOUS SHIFT WITH A FEW 90 DEGREE VALUES
IN THE FAVORED DOWNSLOPE AREAS OVER THE WEST AND THE TRADITIONAL
WARM RAWS SITES. THESE VALUES ARE FAIRLY SIMILAR SEEN UPSTREAM IN
CENTRAL MINNESOTA YESTERDAY.
NAM/HRRR/RAP SHOWING SOME CU DEVELOPMENT DURING THE AFTERNOON OVER
THE CENTRAL AND EAST. THE HRRR AND ONE OF OUR LOCAL RAP
INITIALIZED WRF-ARW RUNS EVEN DEVELOP A FEW SHOWERS AROUND MID
AFTERNOON OVER EASTERN ALGER AND NORTHERN LUCE COUNTY ALONG THE LAKE
MICHIGAN BREEZE BOUNDARY. WITH ALL OF THE OTHER MODELS SHOWING
SIGNIFICANT DRY AIR ABOVE THAT CU...WILL KEEP OUT OF THE FORECAST
FOR NOW...BUT IT WILL BE SOMETHING FOR THE DAY SHIFT TO KEEP AN EYE
ON. OTHERWISE...WOULD EXPECT MOSTLY SUNNY CONDITIONS ACROSS THE REST
OF THE AREA. THIS WILL AID MIXING INTO THE DRIER AIR ALOFT AND ALSO
MIX DOWN SOME OF THE STRONGER WINDS. HIGHEST CORE OF WINDS WILL BE
OVER THE WESTERN CWA...WHERE GUSTS WILL BE IN THE 20-25KT RANGE. AS
FOR DEWPOINTS...ML VALUES FROM THE MODELS ARE IN THE LOWER 50S AND
WILL FOLLOW THAT IDEA (MATCHES VALUES SEEN UPSTREAM YESTERDAY). THIS
PRODUCES MINIMUM RH VALUES IN THE LOWER 30S OVER THE WEST AND
UPPER 30S OVER THE EAST. ALL OF THESE CONDITIONS...COMBINED WITH A
HOLIDAY WEEKEND AND DRY CONDITIONS OVER THE LAST 5-6 DAYS...SUPPORTS
ISSUING A WILDFIRE POTENTIAL STATEMENT OVER THE WEST HALF EVEN
THOUGH THEY HAVE HAD ABOVE NORMAL PRECIPITATION OVER THE LAST 30
DAYS. SINCE COORDINATION WAS PERFORMED YESTERDAY WITH THE DNR...WILL
GO AHEAD AND ISSUE IT THIS MORNING.
AS FOR CONDITIONS UPSTREAM THAT WILL INFLUENCE TONIGHT/S
FORECAST...THE TROUGH OVER WESTERN MINNESOTA WILL KICK OFF
SHOWERS/THUNDERSTORMS IN NORTH CENTRAL AND NORTHEAST MN THIS
AFTERNOON AND EVENING. WITH LIMITED WESTWARD PUSH TO THE SURFACE
TROUGH TODAY AND STORM MOTIONS PARALLEL TO THE WESTERN LAKE SUPERIOR
SHORELINE...WOULDN/T EXPECT MUCH MOVEMENT OF THE
SHOWERS/THUNDERSTORMS INTO WESTERN LAKE SUPERIOR UNTIL THE EVENING
AND MORE LIKELY OVERNIGHT HOURS AS THE SHORTWAVE GIVES IT A PUSH TO
THE EAST. A COUPLE MODELS HINT AT DEVELOPMENT IN NW WISCONSIN THIS
AFTERNOON WHICH WOULD MOVE NE INTO WESTERN LAKE SUPERIOR...SO WILL
MENTION SLIGHT CHANCES WEST OF THE APOSTLE ISLANDS. WITH NO
SIGNIFICANT UPPER FORCING (LARGELY BROAD AND WEAK OVER WESTERN LAKE
SUPERIOR WITH THE BEST IN ONTARIO) AND JUST THE WEAK SURFACE TROUGH
MOVING INTO WESTERN LAKE SUPERIOR...THINK THE OVERALL POTENTIAL FOR
PRECIPITATION IS LOW TONIGHT. THEREFORE...WILL SLOWLY PUSH THE
SLIGHT CHANCE AND CHANCES POPS EAST ACROSS THE WESTERN LAKE WITH
SLIGHT CHANCE VALUES REACHING THE WESTERN THIRD OF THE U.P. DURING
THE OVERNIGHT HOURS. THIS WILL BE DUE TO THE DIMINISHING
SHOWERS/THUNDERSTORMS EXITING NORTHERN MINNESOTA. OVER THE REST OF
THE AREA...WOULD EXPECT MID CLOUDS TO PUSH EAST-NORTHEAST INTO THE
WEST HALF BY DAYBREAK AND THE EAST WILL STAY MOSTLY CLEAR. WITH THE
PRESSURE GRADIENT KEEPING WINDS UP DURING THE NIGHT...THINK LOWS
WILL STAY IN THE LOW 60S EAST AND MID-UPPER 60S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 458 AM EDT FRI JUL 5 2013
SATURDAY...A MAINLY ZONAL MID/UPPER LEVEL PATTERN IS EXPECTED
ACROSS THE NRN CONUS WHILE A CUTOFF LOW DRIFTS FROM THE MID MS
VALLEY TOWARD IN/OH. AT THE SFC...HIGH PRES BUILDING INTO NRN
ONTARIO WILL PUSH A FRONT TOWARD LAKE SUPERIOR. TEMPERATURES
CLIMBING INTO THE MID 80S WITH DEWPOINTS IN THE LOWER 60S WILL
RESULT IN MLCAPE VALUES TO AROUND 1K J/KG OVER THE CNTRL AND WEST.
SINCE THE FORCING WITH ANY WEAK SHORTWAVES WILL REMAIN NORTH OF THE
THE AREA IN THE STRONGER MID LEVEL FLOW...ONLY LOWER END POPS WERE
INCLUDED OVER THE NW HALF.
SAT NIGHT INTO SUN NIGHT...THE MODELS SUGGEST THAT A STRONGER SHORTWAVE
TROUGH WILL MOVE OUT OF THE PLAINS INTO THE NRN GREAT LAKES. THE
COMBINATION OF FORCING WITH THE SHRTWV AND INCREASING LOW LEVEL
THETA-E ADVECTION PUSHING MUCAPE VALUES INTO THE 1000-1500 J/KG
RANGE WILL SUPPORT INCREASING POPS FROM LATE SATURDAY NIGHT INTO
SUNDAY MORNING. HOWEVER...WITH THE ZONAL PATTERN CONFIDENCE IN THE
POSITION/STRENGTH OF THE THE SHRTWV IS LOW. PWAT VALUES TO AROUND
1.75 INCH WILL BRING POTENTIAL FOR SOME LCLY HEAVY RAIN AS THE MAIN
HAZARD...ESPECIALLY OVER THE WRN CWA. IF ENOUGH BREAKS IN THE CLOUD
COVER DEVELOP...AFTERNOON MLCAPE VALUES COULD CLIMB TO AROUND 1K J/KG
SUPPORTING ANOTHER ROUND OF SCT SHRA/TSRA WITH THE FRONT AND LAKE
BREEZE BOUNDARIES OVER THE AREA. HOWEVER...SHEAR VALUES WILL BE
WEAK/MARGINAL TO SUPPORT ORGANIZED STRONGER/SVR STORMS.
MON...ALTHOUGH THE WEAKENING FRONTAL BOUNDAY S EXPECTED TO SAG TO
THE SOUTH OF UPPER MI...THE POTENTIAL REMAINS FOR WEAK SHRTWVS TO
MOVE THROUGH THE AREA THAT COULD RESULT IN ADDITIONAL PCPN KEEPING
SLIGHT CHANCE POPS GOING OVER MAINLY THE CENTRAL AND EAST.
TUE-THU...THE ECMWF/GFS/GEM HAVE COME INTO BETTER AGREEMENT WITH THE
STRONGER SHORTWAVE TROUGH MOVING INTO THE NRN GREAT LAKES BY WED.
QVECTOR CONV AND MOISTURE ADVECTION AHEAD OF THIS FEATURE WILL
SUPPORT INCREASING SHRA/TSRA CHANCES MAINLY FROM TUE NIGHT INTO
EARLY WED. A RETURN TO COOLER CONDITIONS WITH TEMPS BLO NORMAL ARE
EXPECTED BY THU WITH ONLY A CHANCE OF SOME LINGERING LIGHT
SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 722 AM EDT FRI JUL 5 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. AN INCREASING
PRESSURE GRADIENT OVER UPPER MICHIGAN TODAY WILL LEAD TO GUSTY WINDS
THROUGH THE DAYTIME PERIOD. ATTENTION THEN TURNS TO AN APPROACHING
COLD FRONT TONIGHT. THIS WILL BRING INCREASING MID CLOUDS WITH A FEW
SHOWERS POSSIBLY APPROACHING KIWD/KSAW TOWARDS THE END OF THE
PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 458 AM EDT FRI JUL 5 2013
A STRENGTHENING PRESSURE GRADIENT BETWEEN A HIGH IN THE WESTERN
ATLANTIC AND A SLOWLY APPROACHING LOW PRESSURE TROUGH OVER
SOUTH-CENTRAL CANADA WILL ALLOW FOR S-SW WINDS TO CONTINUE THROUGH
SATURDAY. WITH MUCH WARMER TEMPERATURES EXPECTED...THE MARINE LAYER
SHOULD BE QUITE SHALLOW ACROSS SOUTHERN LAKE SUPERIOR...SO GUSTS UP
TO 25 KNOTS COULD BE POSSIBLE ALMOST DOWN TO THE WATER. ACROSS
NORTHERN LAKE SUPERIOR...STRONGER WINDS SHOULD ONLY AFFECT THE
HIGHER PLATFORMS. DRIER AIR SHOULD KEEP THE FOG AT BAY
TODAY...BUT WITH SHOWERS AND THUNDERSTORMS POSSIBLE OVER THE
LAKE LATE TONIGHT THROUGH SUNDAY NIGHT THERE IS THE POTENTIAL
FOR FOG TO DEVELOP. BY SUNDAY NIGHT...WEAK LOW PRESSURE WILL
TRACK EASTWARD ACROSS LAKE SUPERIOR AND BRING LIGHT WINDS UNDER 15
KNOTS. HIGH PRESSURE WILL THEN BUILD IN BEHIND THIS LOW AND KEEP
WINDS LIGHT THROUGH THE BEGINNING OF NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
502 AM EDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EDT FRI JUL 5 2013
THE UPPER TROUGH THAT HAS BEEN INFLUENCING OUR WEATHER OVER THE
LAST SEVERAL DAYS HAS CONTINUED TO WEAKEN AND IS NOW NEARLY CUTOFF
FROM THE MAIN WEST-EAST FLOW ACROSS SOUTHERN CANADA. A SHORTWAVE
CURRENTLY MOVING INTO SOUTHWEST ONTARIO AND NORTHWEST MINNESOTA
WILL SHEAR OUT AND SLIDE NORTH OF THE AREA TODAY AND TONIGHT. AT THE
SURFACE...AREA IS UNDER A RIDGE FROM A HIGH CENTERED IN THE WESTERN
ATLANTIC. THIS LED TO INCREASING SOUTHWESTERLY FLOW YESTERDAY AND
IT WILL CONTINUE TODAY AS THE PRESSURE GRADIENT INCREASES DUE TO A
STATIONARY TROUGH SETUP IN WESTERN ONTARIO TO WEST CENTRAL
MINNESOTA. THIS SOUTHWESTERLY FLOW WILL PULL THE DRY AIR SEEN ON
THE 00Z KMPX SOUNDING OVER THE AREA TODAY AND WILL LEAD TO A NICE
AND WARM SUMMER DAY. MIXING TO 850MB TEMPS OF 17C OVER THE WESTERN
CWA AND 15C OVER THE EAST WILL PRODUCE TEMPERATURES IN THE UPPER 80S
OVER THE WEST AND THE MID 80S OVER THE EAST. THE COOLEST VALUES WILL
BE DOWNWIND OF LAKE MICHIGAN UNDER THE SOUTHWESTERLY FLOW. WILL
CONTINUE THE IDEA OF THE PREVIOUS SHIFT WITH A FEW 90 DEGREE VALUES
IN THE FAVORED DOWNSLOPE AREAS OVER THE WEST AND THE TRADITIONAL
WARM RAWS SITES. THESE VALUES ARE FAIRLY SIMILAR SEEN UPSTREAM IN
CENTRAL MINNESOTA YESTERDAY.
NAM/HRRR/RAP SHOWING SOME CU DEVELOPMENT DURING THE AFTERNOON OVER
THE CENTRAL AND EAST. THE HRRR AND ONE OF OUR LOCAL RAP
INITIALIZED WRF-ARW RUNS EVEN DEVELOP A FEW SHOWERS AROUND MID
AFTERNOON OVER EASTERN ALGER AND NORTHERN LUCE COUNTY ALONG THE LAKE
MICHIGAN BREEZE BOUNDARY. WITH ALL OF THE OTHER MODELS SHOWING
SIGNIFICANT DRY AIR ABOVE THAT CU...WILL KEEP OUT OF THE FORECAST
FOR NOW...BUT IT WILL BE SOMETHING FOR THE DAY SHIFT TO KEEP AN EYE
ON. OTHERWISE...WOULD EXPECT MOSTLY SUNNY CONDITIONS ACROSS THE REST
OF THE AREA. THIS WILL AID MIXING INTO THE DRIER AIR ALOFT AND ALSO
MIX DOWN SOME OF THE STRONGER WINDS. HIGHEST CORE OF WINDS WILL BE
OVER THE WESTERN CWA...WHERE GUSTS WILL BE IN THE 20-25KT RANGE. AS
FOR DEWPOINTS...ML VALUES FROM THE MODELS ARE IN THE LOWER 50S AND
WILL FOLLOW THAT IDEA (MATCHES VALUES SEEN UPSTREAM YESTERDAY). THIS
PRODUCES MINIMUM RH VALUES IN THE LOWER 30S OVER THE WEST AND
UPPER 30S OVER THE EAST. ALL OF THESE CONDITIONS...COMBINED WITH A
HOLIDAY WEEKEND AND DRY CONDITIONS OVER THE LAST 5-6 DAYS...SUPPORTS
ISSUING A WILDFIRE POTENTIAL STATEMENT OVER THE WEST HALF EVEN
THOUGH THEY HAVE HAD ABOVE NORMAL PRECIPITATION OVER THE LAST 30
DAYS. SINCE COORDINATION WAS PERFORMED YESTERDAY WITH THE DNR...WILL
GO AHEAD AND ISSUE IT THIS MORNING.
AS FOR CONDITIONS UPSTREAM THAT WILL INFLUENCE TONIGHT/S
FORECAST...THE TROUGH OVER WESTERN MINNESOTA WILL KICK OFF
SHOWERS/THUNDERSTORMS IN NORTH CENTRAL AND NORTHEAST MN THIS
AFTERNOON AND EVENING. WITH LIMITED WESTWARD PUSH TO THE SURFACE
TROUGH TODAY AND STORM MOTIONS PARALLEL TO THE WESTERN LAKE SUPERIOR
SHORELINE...WOULDN/T EXPECT MUCH MOVEMENT OF THE
SHOWERS/THUNDERSTORMS INTO WESTERN LAKE SUPERIOR UNTIL THE EVENING
AND MORE LIKELY OVERNIGHT HOURS AS THE SHORTWAVE GIVES IT A PUSH TO
THE EAST. A COUPLE MODELS HINT AT DEVELOPMENT IN NW WISCONSIN THIS
AFTERNOON WHICH WOULD MOVE NE INTO WESTERN LAKE SUPERIOR...SO WILL
MENTION SLIGHT CHANCES WEST OF THE APOSTLE ISLANDS. WITH NO
SIGNIFICANT UPPER FORCING (LARGELY BROAD AND WEAK OVER WESTERN LAKE
SUPERIOR WITH THE BEST IN ONTARIO) AND JUST THE WEAK SURFACE TROUGH
MOVING INTO WESTERN LAKE SUPERIOR...THINK THE OVERALL POTENTIAL FOR
PRECIPITATION IS LOW TONIGHT. THEREFORE...WILL SLOWLY PUSH THE
SLIGHT CHANCE AND CHANCES POPS EAST ACROSS THE WESTERN LAKE WITH
SLIGHT CHANCE VALUES REACHING THE WESTERN THIRD OF THE U.P. DURING
THE OVERNIGHT HOURS. THIS WILL BE DUE TO THE DIMINISHING
SHOWERS/THUNDERSTORMS EXITING NORTHERN MINNESOTA. OVER THE REST OF
THE AREA...WOULD EXPECT MID CLOUDS TO PUSH EAST-NORTHEAST INTO THE
WEST HALF BY DAYBREAK AND THE EAST WILL STAY MOSTLY CLEAR. WITH THE
PRESSURE GRADIENT KEEPING WINDS UP DURING THE NIGHT...THINK LOWS
WILL STAY IN THE LOW 60S EAST AND MID-UPPER 60S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 458 AM EDT FRI JUL 5 2013
SATURDAY...A MAINLY ZONAL MID/UPPER LEVEL PATTERN IS EXPECTED
ACROSS THE NRN CONUS WHILE A CUTOFF LOW DRIFTS FROM THE MID MS
VALLEY TOWARD IN/OH. AT THE SFC...HIGH PRES BUILDING INTO NRN
ONTARIO WILL PUSH A FRONT TOWARD LAKE SUPERIOR. TEMPERATURES
CLIMBING INTO THE MID 80S WITH DEWPOINTS IN THE LOWER 60S WILL
RESULT IN MLCAPE VALUES TO AROUND 1K J/KG OVER THE CNTRL AND WEST.
SINCE THE FORCING WITH ANY WEAK SHORTWAVES WILL REMAIN NORTH OF THE
THE AREA IN THE STRONGER MID LEVEL FLOW...ONLY LOWER END POPS WERE
INCLUDED OVER THE NW HALF.
SAT NIGHT INTO SUN NIGHT...THE MODELS SUGGEST THAT A STRONGER SHORTWAVE
TROUGH WILL MOVE OUT OF THE PLAINS INTO THE NRN GREAT LAKES. THE
COMBINATION OF FORCING WITH THE SHRTWV AND INCREASING LOW LEVEL
THETA-E ADVECTION PUSHING MUCAPE VALUES INTO THE 1000-1500 J/KG
RANGE WILL SUPPORT INCREASING POPS FROM LATE SATURDAY NIGHT INTO
SUNDAY MORNING. HOWEVER...WITH THE ZONAL PATTERN CONFIDENCE IN THE
POSITION/STRENGTH OF THE THE SHRTWV IS LOW. PWAT VALUES TO AROUND
1.75 INCH WILL BRING POTENTIAL FOR SOME LCLY HEAVY RAIN AS THE MAIN
HAZARD...ESPECIALLY OVER THE WRN CWA. IF ENOUGH BREAKS IN THE CLOUD
COVER DEVELOP...AFTERNOON MLCAPE VALUES COULD CLIMB TO AROUND 1K J/KG
SUPPORTING ANOTHER ROUND OF SCT SHRA/TSRA WITH THE FRONT AND LAKE
BREEZE BOUNDARIES OVER THE AREA. HOWEVER...SHEAR VALUES WILL BE
WEAK/MARGINAL TO SUPPORT ORGANIZED STRONGER/SVR STORMS.
MON...ALTHOUGH THE WEAKENING FRONTAL BOUNDAY S EXPECTED TO SAG TO
THE SOUTH OF UPPER MI...THE POTENTIAL REMAINS FOR WEAK SHRTWVS TO
MOVE THROUGH THE AREA THAT COULD RESULT IN ADDITIONAL PCPN KEEPING
SLIGHT CHANCE POPS GOING OVER MAINLY THE CENTRAL AND EAST.
TUE-THU...THE ECMWF/GFS/GEM HAVE COME INTO BETTER AGREEMENT WITH THE
STRONGER SHORTWAVE TROUGH MOVING INTO THE NRN GREAT LAKES BY WED.
QVECTOR CONV AND MOISTURE ADVECTION AHEAD OF THIS FEATURE WILL
SUPPORT INCREASING SHRA/TSRA CHANCES MAINLY FROM TUE NIGHT INTO
EARLY WED. A RETURN TO COOLER CONDITIONS WITH TEMPS BLO NORMAL ARE
EXPECTED BY THU WITH ONLY A CHANCE OF SOME LINGERING LIGHT
SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 121 AM EDT FRI JUL 5 2013
VFR CONDITIONS TO PREVAIL THROUGH THE FORECAST PERIOD. A WEAK
DISTURBANCE TO THE WEST OF THE REGION WILL CONTINUE TO MAKE SLOW
EASTWARD PROGRESS TOWARD UPPER MICHIGAN THROUGH SATURDAY AFTERNOON
AND EVENING. AHEAD OF THIS FEATURE...THE SURFACE PRESSURE GRADIENT
WILL TIGHTEN UP TODAY RESULTING GUSTY SSW WINDS DEVELOPING. GUSTS
SHOULD STAY AT OR BELOW 22 KTS UNTIL DIMINISHING DURING THE LATE
AFTERNOON. INCREASING CLOUDINESS IN THE LATE AFTERNOON AND EARLY
EVENING OVER THE WESTERN TAF SITES IS THE HARBINGER OF A SLIGHT
CHANCE FOR SHOWERS AND THUNDERSTORMS AT KCMX AND KIWD...MAINLY AFTER
03Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 458 AM EDT FRI JUL 5 2013
A STRENGTHENING PRESSURE GRADIENT BETWEEN A HIGH IN THE WESTERN
ATLANTIC AND A SLOWLY APPROACHING LOW PRESSURE TROUGH OVER
SOUTH-CENTRAL CANADA WILL ALLOW FOR S-SW WINDS TO CONTINUE THROUGH
SATURDAY. WITH MUCH WARMER TEMPERATURES EXPECTED...THE MARINE LAYER
SHOULD BE QUITE SHALLOW ACROSS SOUTHERN LAKE SUPERIOR...SO GUSTS UP
TO 25 KNOTS COULD BE POSSIBLE ALMOST DOWN TO THE WATER. ACROSS
NORTHERN LAKE SUPERIOR...STRONGER WINDS SHOULD ONLY AFFECT THE
HIGHER PLATFORMS. DRIER AIR SHOULD KEEP THE FOG AT BAY
TODAY...BUT WITH SHOWERS AND THUNDERSTORMS POSSIBLE OVER THE
LAKE LATE TONIGHT THROUGH SUNDAY NIGHT THERE IS THE POTENTIAL
FOR FOG TO DEVELOP. BY SUNDAY NIGHT...WEAK LOW PRESSURE WILL
TRACK EASTWARD ACROSS LAKE SUPERIOR AND BRING LIGHT WINDS UNDER 15
KNOTS. HIGH PRESSURE WILL THEN BUILD IN BEHIND THIS LOW AND KEEP
WINDS LIGHT THROUGH THE BEGINNING OF NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...RJT
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
634 PM CDT SAT JUL 6 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 152 PM CDT SAT JUL 6 2013
RESIDUAL CLD CVR AND -SHRA/SPRINKLES ACROSS WC/CENTRAL/EC MN HAVE
HAMPERED AFTN HEATING AND LIMITED THE INSTABILITY WHERE BETTER
CONVERGENCE IS NOTED ABV THE BOUNDARY LAYER. BETTER INSTABILITY
AND LESS CIN IS NOTED IN SD/ND WHERE A SVR WATCH HAS BEEN POSTED
FOR PARTS OF THEIR AREA. DUE TO THE LACK OF HEATING WHERE CHC/S OF
BETTER MOISTURE CONVERGENCE IS NOTED IN WC/CENTRAL MN...WILL KEEP
CHC/S OF SHRA/TSRA LOWER THAN 50%...WITH BETTER CHC/S DEVELOPING
OVERNIGHT AS THE FRONTAL BOUNDARY FINALLY MOVES EASTWARD INTO
WESTERN MN AFT MIDNIGHT. SVR WX THREATS WILL REMAIN LOW FOR OUR
REGION...WITH ONLY AN OUTSIDE CHC OF SVR WIND GUST/HAIL IN WC MN
DURING THE EARLY EVENING HRS IF ENOUGH HEATING DEVELOPS. BY SUNDAY
MORNING...THE SFC FRONT SHOULD BE ACROSS CENTRAL MN/INTO SW MN.
BASED ON THE SLOWER MOVEMENT ON THE LATEST MODEL RUNS...WILL HOLD
ONTO PRECIPITATION CHC/S ACROSS SC MN/EC MN/WC WI SUNDAY AFTN.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 PM CDT SAT JUL 6 2013
WEAK SFC LOW WITH ILL-DEFINED ASSOCIATED WMFNT AND CDFNT WILL
SETTLE OVER SRN MN AT THE START OF SUN NIGHT WHILE A NE-SW
ORIENTED RIDGE AXIS ALOFT SHIFTS ACRS THE AREA. THE EWD MOVEMENT
OF BOTH FEATURES SUN NIGHT INTO MON WILL ALLOW FOR THE BULK OF THE
SHWRS AND TSTMS TO PUSH OFF TO THE E...BRINGING A BRIEF DRYING OUT
PERIOD FOR MUCH OF THE MPX CWFA...EXCEPT FOR FAR SRN MN WHICH MAY
HAVE SOME RAIN STRAGGLERS. WITH DEEP MOISTURE REMAINING IN PLACE
INVOF THE LOW PRES CENTER ANS ITS ASSOCIATED FRONTS...SOME ISOLD
TO SCTRD SHWRS/TSTMS MAY STILL DEVELOP JUST S OF THE CWFA FOR MUCH
OF THE DAY MON. ANY ACTIVITY IS EXPECTED TO BE WEAK WITH THE RIDGE
AXIS ALOFT AND SFC FRONTS LOCATED S/E OF THE AREA. HOWEVER...CHCS
FOR PRECIP IMPROVE GREATLY MON NIGHT INTO TUE AS THE FNT S OF THE
AREA BEGINS TO LIFT BACK N AS A WMFNT ASSOCIATED WITH ANOTHER LOW
PRES CENTER DEVELOPING OVER ERN MT AND THE WRN DAKOTAS. A POTENT
TROF AXIS WILL SWING SE FROM SRN CANADA...PICKING UP THIS LOW PRES
CENTER AND SHOVING IT EWD ACRS CENTRAL-NRN MN DURG THE DAY ON TUE.
ENHANCED LLJ AHEAD OF THIS CDFNT ALONG WITH A SSW MOISTURE FETCH
WILL AGAIN AID IN STRONG TSTM DEVELOPMENT...LIKELY SCTRD CLUSTERS
FOR MUCH OF TUE. TIMING STILL AN ISSUE AMONG THE MODELS BUT LATER
RUNS SEEM TO AGREE THAT EARLIER RATHER THAN LATER WORKS BETTER.
ALSO AIDING LIFT WILL BE THE DEVELOPMENT OF A SECONDARY LOW PRES
CENTER ALONG THE SFC FNT...SO HAVE NUDGED POPS INTO THE LIKELY
CATEGORY FOR THE ENTIRE CWFA. TSTMS LOOKS TO BE STRONGEST OVER NRN
PORTIONS OF MN BUT EVEN SOME SRN PORTIONS MAY WELL BE SUBJECT TO
HEAVY RAIN AND/OR STRONG STORMS WITH GUSTY WINDS. ONCE THIS SYSTEM
EXITS THE AREA BY LATE TUE NIGHT...THE LONGWAVE TROUGH ALOFT WILL
SHIFT OFF TO THE E...ALLOWING A BUILDING RIDGE OVER THE ROCKIES TO
GRADUALLY APPROACH WITH EXPANDING SFC HIGH PRES UNDERNEATH. THIS
WILL MAKE FOR A DRY FCST FOR WED THRU THU NIGHT. IN ADDITION TO
THE PRECIP-FREE FCST...A SLIGHT CHANGE IN AIRMASS CAN BE EXPECTED
AS PRONOUNCED NW FLOW REDUCES BOTH TEMPS AND HUMIDITY LEVELS. THE
RIDGE OVER THE AREA WILL FLATTEN AND SHIFT E...ALLOWING SEVERAL
WAVE PERTURBATIONS TO GLIDE THROUGH THE AREA. DIFFICULT TO TELL AT
THIS POINT HOW THIS WILL EVOLVE BUT CONFIDENCE IS GROWING IN
SEEING SOME PRECIPITATION FOR FRI AND POSSIBLY FRI NIGHT SO HAVE
KEPT CHC POPS GOING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 623 PM CDT SAT JUL 6 2013
MUCH OF THE AREA IS CURRENTLY CAPPED WITH ONLY SOME LIGHT ELEVATED
SHRA/SPRINKLES GETTING GOING AT THE CURRENT TIME. HOWEVER... ONCE
THINGS DECOUPLE THIS EVENING WE SHOULD SEE THE LOW LEVEL JET
INCREASE ENOUGH TO GET SLIGHTLY MORE ACTIVITY GOING OVER NORTHWEST
AND WEST-CENTRAL MINNESOTA ALONG THE INSTABILITY GRADIENT.
EXPECTATIONS ARE FOR A SOMEWHAT MORE ORGANIZED MCS TO THEN WORK
EAST-SOUTHEAST ACROSS PARTS OF NORTHERN/CENTRAL MINNESOTA DURING
THE LATTER HALF OF THE EVENING AND INTO THE OVERNIGHT... ALTHOUGH
THE HOPWRF AND HRRR DON/T SUGGEST ANYTHING TOO ROBUST AT THIS
POINT IN TIME... AND INDICATE A WEAKENING TREND AS WHATEVER FORMS
WORKS INTO EAST CENTRAL MINNESOTA AND WEST-CENTRAL WISCONSIN
OVERNIGHT. SINCE NOTHING HAS FORMED VERY FAR SOUTH YET... MUCH
WILL OBVIOUSLY DEPEND ON IF/WHEN/WHERE THINGS CAN DEVELOP ALONG
NOSE OF FAIRLY WEAK LOW LEVEL JET OVER THE NEXT FOUR HOURS. SO...
FORECAST IS FAIRLY LOW CONFIDENCE AT THIS POINT... AND STAYED ON
THE OPTIMISTIC SIDE IN TERMS OF TSRA/CIG/VSBY AS A RESULT. WINDS
WILL BE SHIFTING AROUND TO THE WEST AND WEST-NORTHWEST LATE
TONIGHT AND ON SUNDAY AS WE GET ONTO THE BACKSIDE OF THE SURFACE
FRONT/TROUGH... AND AT THIS POINT THERE DOESN/T APPEAR TO BE MUCH
POTENTIAL FOR SHRA/TSRA ON SUNDAY WITH WEAK RIDGING OVER THE AREA.
KMSP...TAF REFLECTS OVERALL EXPECTATIONS... BUT CONFIDENCE IS
FAIRLY LOW WITH RESPECT TO THE DETAILS ON SHRA/TSRA
DEVELOPMENT/TIMING LATER TONIGHT. IT IS POSSIBLE THAT WE WILL ONLY
SEE SOME LIGHT SHRA/SPRINKLES OUT OF THE HIGH-BASED ACTIVITY
CURRENTLY EVIDENT ON RADAR TO THE WEST. HOWEVER... THE VARIOUS
HIGH RESOLUTION SOLUTIONS AND PROXIMITY TO THE INSTABILITY
GRADIENT AND LOW LEVEL JET STILL WARRANT SOME MENTION OF TSRA
OVERNIGHT WITH A POSSIBLE MCS/LINEAR SYSTEM MOVING THROUGH THE
AREA... WITH KMSP PERHAPS ON THE SOUTH END OF THAT. GIVEN LOW
CONFIDENCE... KEPT FORECAST CEILINGS AND VISIBILITIES FAIRLY
HIGH... AND WILL JUST NEED TO KEEP AN EYE ON THINGS THROUGH THE
NIGHT AND AMEND AS NEEDED.
/OUTLOOK FOR KMSP/
SUNDAY OVERNIGHT...VFR CONDITIONS EXPECTED. VARIABLE WIND LESS
THAN 5 KT.
MONDAY...VFR CONDITIONS EXPECTED... MVFR CEILINGS AND VISIBILITIES
POSSIBLE LATE WITH CHANCE OF SHRA/TSRA. VARIABLE WIND LESS THAN 5
KT BECOMING SOUTHEAST 5 TO 10 KT.
MONDAY NIGHT...MVFR CEILINGS EXPECTED... MVFR VISIBILITIES
POSSIBLE WITH CHANCE SHRA/TSRA. EAST WIND 10 TO 15 KT BECOMING NORTHEAST.
TUESDAY...VFR CONDITIONS EXPECTED... MVFR CEILINGS AND
VISIBILITIES POSSIBLE WITH CHANCE OF SHRA/TSRA. NORTHEAST WIND 5
TO 15 KT BECOMING VARIABLE LESS THAN 10 KT.
TUESDAY NIGHT AND WEDNESDAY...VFR CONDITIONS EXPECTED. NORTHWEST
WIND 10 TO 20 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...JPC
AVIATION...
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1136 PM CDT THU JUL 4 2013
.SHORT TERM...(TONIGHT - SUNDAY)
SCATTERED THUNDERSTORMS HAVE DEVELOPED WEST OF A LINE FROM TABLE
ROCK TO LAKE OF THE OZARKS. RAP MIXED LAYER CAPE VALUES ARE
RANGING FROM 1500-2000 J/KG. THE COMBINATION OF THIS INSTABILITY
AND AN INVERTED V STRUCTURE TO THE LOWER TROP...COULD CREATE A
LIMITED RISK FOR SOME WIND GUSTS THIS AFTERNOON AND EVENING. WITH
-20 LEVELS BEING SO LOW...WE THERE COULD BE A LIMITED HAIL RISK
WITH SOME OF THE STRONGER UPDRAFTS. ANYONE PARTICIPATING IN FOURTH
OF JULY OUTDOOR ACTIVITIES WILL NEED TO WATCH OUT FOR LIGHTNING
STRIKES UNDER THESE UPDRAFTS.
MUCH LIKE LAST NIGHT...A FEW STORMS COULD LINGER WELL INTO THE
EVENING HOURS...AND EVENTUALLY DISSIPATE PRIOR TO MIDNIGHT.
HUMIDITY LEVELS HAVE CREPT UP A LITTLE WITH THE COMMENCEMENT OF
WEAK SOUTHERLY WINDS. THEREFORE OVERNIGHT LOWS WILL BE A LITTLE
WARMER THAN THE PREVIOUS FEW NIGHTS.
A LOWER FREQUENCY OF SHOWERS AND STORMS WILL OCCUR ON FRIDAY
AFTERNOON...AS THE MAIN UPPER LEVEL CIRCULATION SLOWLY MOVES INTO
WESTERN ILLINOIS. HOWEVER...THE BROAD OVERALL TROUGH AXIS WILL
STILL BE ACROSS THE OZARKS. SO CHANCES ARE NOT ZERO FOR
FRIDAY...AND EVEN LOWER CHANCES FOR RAIN WILL OCCUR SATURDAY AND
SUNDAY AFTERNOONS.
LOOK FOR THE WARMING TREND TO PERSIST THROUGH THE WEEKEND...AS
AFTERNOON HIGHS WARM BACK INTO THE UPPER 80S AND LOWER 90S BY
SUNDAY. HUMIDITY WILL ALSO GRADUALLY INCREASE WITH TIME.
.LONG TERM...(MONDAY - THURSDAY)
BOTH THE ECMWF AND THE GFS CONFINE THE SUMMERTIME HIGH CENTER OVER
THE DESERT SOUTHWEST THROUGH MOST OF NEXT WEEK. THE OZARKS WILL BE
POSITIONED ALONG THE NORTHEAST PERIPHERY OF THIS FEATURE...KEEPING
TEMPERATURES FROM GETTING TOO OUT OF HAND...AND KEEPING THE REGION
ALIVE FOR PRECIP CHANCES.
THIS IS A FAIRLY DECENT PATTERN FOR AFTERNOON PULSE
CONVECTION...ESPECIALLY SINCE DEEP MOISTURE WILL GRADUALLY BUILD
INTO SOUTHERN MISSOURI. CHANCES FOR NOCTURNAL STORM COMPLEXES ARE
ALIVE AS WELL UNDER THIS REGIME.
THE BEST SIGNAL FOR A POSSIBLE MCS WOULD BE TUESDAY NIGHT INTO
WEDNESDAY MORNING. BUT TRYING TO FORECAST SOMETHING LIKE THIS 6
DAYS OUT IS PRETTY CHALLENGING.
HAVE A GREAT HOLIDAY WEEKEND AND STAY SAFE.
CRAMER
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1134 PM CDT THU JUL 4 2013
CONVECTION HAS ENDED OVER THE AREA TONIGHT. UPPER LOW WILL
CONTINUE TO VERY SLOWLY DRIFT EAST-NORTHEAST OVER THE NEXT 24 HOUR
PERIOD. WILL LIKELY SEE A REPEAT OF TODAY WITH LATE
MORNING/AFTERNOON/EARLY EVENING WIDELY SCATTERED CONVECTION. HAVE
KEPT THINGS VFR FOR NOW.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...CRAMER
LONG TERM...CRAMER
AVIATION...LINDENBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
621 PM CDT SAT JUL 6 2013
.AVIATION...00Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS
THROUGH THE PERIOD. SOUTHEAST WINDS AT 14 KNOTS GUSTING TO 20 TO
24 KNOTS COULD LINGER AT KLNK/KOMA THROUGH 01Z...THEN GUSTS SHOULD
DIMINISH OVERNIGHT. A FRONTAL BOUNDARY WILL BE MOVING INTO THE
AREA SUNDAY MORNING...WHICH SHOULD BRING A WIND SHIFT TO THE
NORTHEAST AT KOFK BY 15Z. COULD ALSO SEE CONVECTION DEVELOP AT
KOFK AFTER 20Z...BUT TOO FAR OUT TO INCLUDED IN THE FORECAST AT
THIS TIME.
DEWALD
&&
.PREV DISCUSSION... /ISSUED 331 PM CDT SAT JUL 6 2013/
DISCUSSION...
OFF-AND-ON THUNDERSTORM CHANCES OVER THE NEXT SEVERAL DAYS ARE THE
MAIN FORECAST CONCERNS.
MORNING UPPER AIR CHARTS SHOWED HIGH PRESSURE IN THE SOUTHWEST
STATES AND OFF THE ATLANTIC COAST WITH A WEAK LOW IN THE MIDDLE
MOVING INTO THE OHIO VALLEY REGION. FAST WESTERLY FLOW COVERED THE
NORTHERN TIER OF THE CONUS. OUR AREA REMAINED IN THE TRANSITION ZONE
OF HIGHER HEIGHTS TO THE SOUTH AND FAST FLOW TO THE NORTH. AT THE
SURFACE...A WIND SHIFT LINE WAS NOTED IN CENTRAL SOUTH DAKOTA AND
WESTERN NEBRASKA...TIED TO A SHORTWAVE EXTENDING FROM THE NORTHERN
PLAINS INTO NEBRASKA. AND A COLD FRONT WAS PUSHING INTO THE WESTERN
DAKOTAS.
LIGHT SHOWERS OR SPRINKLES THAT MOVED ACROSS EASTERN NEBRASKA THIS
MORNING HAVE LEFT OUR AREA CAPPED TO CONVECTION SO FAR THIS
AFTERNOON. RAP SOUNDINGS SUGGEST SURFACE-BASED CAPES WERE TOPPING
1000 J/KG...BUT INHIBITION WAS STILL ROBUST. BUT WITH TEMPERATURES
WARMING A FEW MORE DEGREES LATE IN THE DAY...COULD SEE AN ISOLATED
SHOWER OR STORM POP UP THIS EVENING...PROBABLY IN WESTERN IOWA. THEN
LATER TONIGHT...WIND SHIFT LINE WILL SETTLE SOUTHEAST INTO OUR AREA
AS SHORTWAVE MOVES OFF TO THE EAST. INSTABILITY WAS STRONG IN
CENTRAL/WESTERN SOUTH DAKOTA NEAR/AHEAD OF WIND SHIFT...SO AM
EXPECTING STORMS TO FIRE THERE LATE THIS AFTERNOON OR EVENING. THIS
ACTIVITY SHOULD PUSH OFF TO THE EAST BUT COULD SKIRT OUR NORTHERN
CWA. OTHERWISE MORE GENERAL THUNDER CHANCES ARE POSSIBLE WITH WIND
SHIFT LINE AS IT MOVES INTO EASTERN NEBRASKA AFTER MIDNIGHT.
SURFACE BOUNDARY WILL REMAIN IN OUR AREA DURING THE DAY SUNDAY. NOT
MUCH NOTED IN MID LEVEL FLOW TO KICK UP CONVECTION ALONG THE
FRONT...SO WILL HAVE TO WAIT UNTIL LATE AFTERNOON WHEN INSTABILITY
IS MAXIMIZED. THEN FRONT/WIND SHIFT SHOULD BE OVER NORTHEAST
NEBRASKA...SO HAVE MAINTAINED A SMALL CHANCE FOR THUNDERSTORMS
THERE. BETTER CHANCES FOR STORMS WILL COME SUNDAY NIGHT INTO MONDAY
AS ANOTHER SHORTWAVE MOVES INTO THE PLAINS. MEANWHILE FRONTAL
BOUNDARY WILL SETTLE SOUTH SUNDAY NIGHT...THE LIFT BACK NORTH ON
MONDAY. COMBINATION OF TEMPERATURES CLIMBING INTO THE 90S AND
COOLING TEMPERATURES ALOFT WITH SHORTWAVE WILL PRODUCE CAPES
APPROACHING 3000 J/KG WITH 30KT OF 0-6KM BULK SHEAR MONDAY
AFTERNOON. SO WILL CONTINUE OUR SMALL CHANCES FOR STORMS SUNDAY
NIGHT AS BOUNDARY SETTLES SOUTH...AND HIGHER CHANCES MONDAY
AFTERNOON IN THE NORTH WHERE BOUNDARY/INSTABILITY WILL BE MAXIMIZED.
SOME SEVERE STORMS ARE POSSIBLE GIVEN INSTABILITY/SHEAR.
STORMS CHANCES SHOULD CONTINUE MONDAY NIGHT INTO TUESDAY AS FRONTAL
BOUNDARY REMAINS IN OUR AREA...REINFORCED BEHIND EXITING SHORTWAVE.
INSTABILITY WILL AGAIN APPROACH 3000 J/KG ALONG BOUNDARY TUESDAY
AFTERNOON...WITH A TAD GREATER SHEAR. SO AGAIN SEVERE IS POSSIBLE
TUESDAY AFTERNOON.
FRONT IS FORECAST TO SETTLE SOUTH OF OUR AREA ON WEDNESDAY...SO WILL
KEEP WEDNESDAY AND THURSDAY DRY. UPPER RIDGE BEGINS TO BUILD INTO
OUR AREA FRIDAY AND SATURDAY SIGNALING A RETURN TO WARMER
TEMPERATURES. AS RIDGE BUILDS...WARM ADVECTION REGIME ON FRIDAY
COULD SPARK STORMS...BUT DRY AFTER THAT AS MID LEVEL TEMPS WARM.
TEMPERATURES INTO MONDAY AND TUESDAY WILL EASILY REACH THE 90S...BUT
COULD HOLD IN THE 80S WHERE STORMS/CLOUDS LINGER. A LITTLE COOLER
WEDNESDAY AND THURSDAY WITH HIGHS IN THE 80S...BUT A RETURN TO 90S
LOOK LIKELY FRIDAY AND SATURDAY.
DERGAN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
402 PM CDT FRI JUL 5 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 348 PM CDT FRI JUL 5 2013
MAIN FORECAST CONCERNS WILL BE SHOWERS TONIGHT AND TEMPERATURES.
SATELLITE AND SURFACE OBSERVATIONS SHOW SOME MID AND HIGH LEVEL
CLOUDS ACROSS THE AREA AND ANOTHER BAND OF THEM TO THE WEST. THE
BAND TO THE WEST WILL BE MOVING INTO THE AREA DURING THE NIGHT.
THERE IS AN UPPER LEVEL WAVE THAT MOVES THROUGH THE AREA...MAINLY TO
THE NORTH OF THE FORECAST AREA. MODELS HAVE VARYING METHODS OF HOW
THEY HANDLE THE WAVE TONIGHT. THE NAM AND THE HRRR BOTH BRING SOME
PRECIPITATION TO THE NORTHERN PART OF THE FORECAST AREA WHILE THE
GFS AND THE 4KM WRF REMAIN DRY. HAVE KEPT AT LEAST SOME OF THE
SHOWERS THAT WERE IN THE FORECAST. IT IS A SMALL CHANCE OF LIGHT
SHOWERS. EXPECT THAT IT WILL BE SIMILAR TO LAST NIGHT AND THIS
MORNING WITH A FEW SPOTTY SHOWERS OR SPRINKLES. TEMPERATURES ARE
EXPECTED TO BE ON THE WARM SIDE.
ON SATURDAY ANOTHER UPPER LEVEL WAVE MOVES THROUGH THE AREA. AT THE
SURFACE A LOW PRESSURE SYSTEM AND WEAK COLD FRONT ON THE HIGH PLAINS
DRIFTS TO THE EAST DURING THE DAY. AS THE WAVE MOVES OVER THE NAM
AND THE 4KM WRF DEVELOP SOME THUNDERSTORMS ALONG THE FRONT. THE MAIN
QUESTION IS WHETHER THEY MOVE INTO THE FORECAST AREA DURING THE
AFTERNOON. THE LATEST RUNS OF THE MODELS HAVE TRENDED A LITTLE
FURTHER WEST WITH THE FRONT SO EXPECT THAT THE THUNDERSTORMS WILL
HOLD OFF UNTIL THE EVENING.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 348 PM CDT FRI JUL 5 2013
THE UPPER AIR PATTERN WILL BECOME MORE OF A ZONAL FLOW REGIME SUNDAY
THROUGH WEDNESDAY WITH THE JET STREAM FLOWING ACROSS THE NORTHERN
TIER OF OUR COUNTRY. THIS IS A CHANGE FROM THE MORE MERIDIONAL FLOW
AND UPPER TROUGH THAT HAS DOMINATED OUR REGION FOR THE LAST SEVERAL
DAYS. CONSEQUENTLY...EXPECT WARMER TEMPERATURES THAT SHOULD BE AT
LEAST NEAR NORMAL TO LIKELY ABOVE NORMAL MOST DAYS THROUGH THE
PERIOD. THE BIGGER SYNOPTIC SYSTEMS WILL REMAIN WELL NORTH OF US
THROUGH THE PERIOD WITH OUR PRECIPITATION CHANCES COMING FROM WEAKER
FORCED EVENTS SUCH AS MINOR FRONTAL BOUNDARIES AND WIND SHIFT
TROUGHS. WE WILL ALSO HAVE TO WATCH OUT FOR CONVECTION THAT FORMS
OVER THE HIGH PLAINS THAT COULD WORK INTO OUR AREA FROM THE WEST
DURING THE EVENING AND OVERNIGHT PERIODS. OVERALL...PRECIPITATION
CHANCES WILL BE LOW AND RAIN EVENTS WILL LIKELY BE MORE ISOLATED IN
NATURE. THAT BEING SAID...THERE ARE NUMEROUS SMALL CHANCES OF
PRECIPITATION IN THE FORECAST BUT IF YOU ARE LOOKING FOR RAIN I
WOULD NOT GET YOUR HOPES UP TOO MUCH AS THESE ARE ALL LOW END WEAKLY
FORCED EVENTS. HIGH TEMPERATURES THROUGH THE PERIOD WILL GENERALLY
BE IN THE 90S WITH MAYBE SEVERAL 100 DEGREE DAYS ACROSS NORTHERN
KANSAS. IF THE UPPER RIDGE DOES BUILD IN TO THE CENTRAL PLAINS
NEXT FRIDAY IT COULD LEAD TO A VERY HOT START TO NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1220 PM CDT FRI JUL 5 2013
MID AND HIGH LEVEL CLOUDS CONTINUE TO MOVE ACROSS THE AREA THIS
AFTERNOON. THE SHOWERS HAVE MOVED OUT OF THE AREA AND ARE NOT
EXPECTED TO REDEVELOP THIS AFTERNOON. AT LEAST SOME CLOUDS ARE
EXPECTED TO LINGER THROUGH THE PERIOD AND REMAIN VFR. SOUTH WINDS
ARE EXPECTED THROUGH THE PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...WESELY
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
117 PM CDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI JUL 5 2013
LOW PRESSURE WILL REMAIN ANCHORED ACROSS THE WRN HIGH PLAINS THIS
AFTERNOON AND TONIGHT. THIS WILL SET UP SOUTHERLY WINDS AS A WARM
FRONT RETREATS ACROSS NRN NEBRASKA. THE HRRR SUGGESTS THE ONGOING
SHOWERS...RAIN AND ISOLATED THUNDERSTORMS ACROSS NWRN NEB...ERN WY
AND SWRN SD WILL CONTINUE MOVING SLOWLY EAST TODAY AFFECTING NRN
NEB ALONG AND NORTH OF A WARM FRONT EXPECTED TO REMAIN ALONG
HIGHWAY 20 FOR THE MOST PART. SOUTH OF THIS FRONT TEMPERATURES
COULD RISE INTO THE MID 90S WHILE AREAS NORTH OF THE FRONT REMAIN
IN THE UPPER 80S...PERHAPS COOLER DEPENDING ON THE OUTCOME OF THE
RAIN WHICH MOST MODELS SHOW DECAYING IN THE STABLE NERN QUADRANT
OF THE H500MB UPPER LEVEL RIDGE.
DIURNALLY DRIVEN ISOLATED THUNDERSTORMS MIGHT DEVELOP SOUTH OF THE
WARM FRONT WITH THE STRONG HEATING. THESE STORMS SHOULD BE ELEVATED
AS DEW POINTS AT THE SFC REMAIN IN THE LOWER 50S. NO ORGANIZED
SEVERE WEATHER IS EXPECTED WITH ANY STORMS WHICH DEVELOP GIVEN THE
LOW LEVEL MOISTURE PROFILES. STILL ELEVATED STORMS MIGHT PRODUCE
STRONG OR SEVERE WIND GUSTS GIVEN THE RELATIVELY WEAK WINDS ALOFT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI JUL 5 2013
THE BIG NEWS IS THAT MOISTURE WILL BE ON THE INCREASE DURING THE
BEGINNING OF THIS PERIOD. PRECIPITABLE WATER VALUES HAVE BEEN
RUNNING AROUND 0.6 TO 0.8 INCHES LATELY...BUT WILL INCREASE TO
OVER 1.25 INCHES FOR SATURDAY AND SUNDAY. THE AVERAGE FOR THIS
TIME OF YEAR IS 1.08 INCHES...SO THIS WEEKENDS PWATS WILL BE IN
THE 75TH PERCENTILE COMPARED TO CLIMATOLOGY.
THE UPPER RIDGE WILL BEGIN TO BREAK DOWN BY SATURDAY...WITH A MORE
ZONAL FLOW SETTING UP AND WEAK DISTURBANCES IN THE FLOW EXPECTED.
WITH THE INCREASED MOISTURE...INSTABILITY WILL EXIST ACROSS THE
REGION ON SATURDAY AND SUNDAY. THE FOCUS FOR THUNDERSTORMS WILL BE
ALONG A FRONTAL BOUNDARY THAT WILL EXIST ACROSS THE NORTHWESTERN
FORECAST AREA ON SATURDAY. CAPE LOOKS TO BE AROUND 2000-3000 J/KG IN
THE NORTH SATURDAY NIGHT...WITH 0-6 KM SHEAR RUNNING MAINLY AROUND
30 KTS WITH THE NW APPROACHING 40 KTS. SOME SEVERE STORMS WILL BE
POSSIBLE...WITH THE BEST CHANCE IN THE NORTH SATURDAY NIGHT. ON
SUNDAY...THE FRONT MAKES SOME PROGRESS SOUTH...FOCUSING THE
AFTERNOON THUNDERSTORM ACTIVITY IN THAT AREA. HOWEVER...MODELS
INDICATE THAT THERE MAY BE SOME ACTIVITY MOVING OFF THE HIGHER
TERRAIN OF WYOMING AND INTO NEBRASKA OVERNIGHT SUNDAY NIGHT. CAPES
WILL GENERALLY RUN 1500-2500 J/KG...WITH THE BEST DEEP SHEAR IN THE
NORTHWEST AROUND 40 KTS YIELDING THE BEST CHANCE FOR SEVERE WEATHER
IN THAT AREA. TEMPERATURES WILL BE IN THE LOW TO MID 90S NORTH TO
NEAR 100 SOUTH ON SATURDAY. ON SUNDAY TEMPS WILL COOL A BIT TO THE
UPPER 80S TO LOW 90S IN MOST AREAS...EXCEPT SOME UPPER 90S ARE
EXPECTED IN THE FAR SOUTH.
NEXT WEEK...AN UPPER LEVEL WAVE WILL MOVE THROUGH THE DAKOTAS EARLY
IN THE WEEK...FOLLOWED BY UPPER RIDGING OVER THE REGION TOWARD THE
END OF THE WEEK. THE PWATS STAY RATHER HIGH THROUGH MID WEEK...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 115 PM CDT FRI JUL 5 2013
WEAK WAVE MOVING ACROSS WESTERN NEBRASKA THIS AFTERNOON. MAINLY
SPRINKLES OR LIGHT RAIN...AS NO LIGHTNING STRIKES SEEN YET. AS
THE AFTERNOON CONTINUES TO WARM...MORE INSTABILITY WILL DEVELOP
AND SHOULD GET SOME ISOLD THUNDER TO MIX IN WITH THE SHOWERS.
COULD SEE SOME MINOR IMPACT AT BOTH TERMINAL SITES...HOWEVER DID
NOT INCLUDE THUNDER YET. MORE ROBUST SHOWERS ACROSS NW NEB HAVE
LED TO A TEMP GROUP FOR KVTN...WHILE VCSH WAS INCLUDED FOR KLBF.
AS THE WAVE MOVES THROUGH...LINGERING MID AND HIGH CLOUDS...THEN
DECREASE CLOUDS LATE TONIGHT INTO THE MORNING. WINDS WILL
GENERALLY REMAIN SOUTH TO SOUTHEAST WITH AFTERNOON GUSTS TO 20
KTS...OTHERWISE 13 KTS OR LESS.
&&
.FIRE WEATHER...
ISSUED AT 315 AM CDT FRI JUL 5 2013
RELATIVE HUMIDITY FALLS TO BETWEEN 20 AND 30 PERCENT THIS AFTERNOON.
ALTHOUGH FUEL STATUS IS NEGATIVE FOR FIRE GROWTH...ONE WILD FIRE
DEVELOPED NEAR ROSCOE THURSDAY AFTERNOON SUGGESTING FUELS MAY BE
FAVORABLE IN SOME AREAS. THE AREA CONCERN FOR WILD FIRES IS WHERE
WINDS WILL BE STRONGEST AND THIS WOULD BE SOUTH OF A WARM FRONT FCST
TO BE ALONG OR NEAR HIGHWAY 20. ISOLATED THUNDERSTORMS ARE POSSIBLE
THIS AFTERNOON BUT MAINLY ALONG AND NORTH OF THE WARM FRONT. WINDS
SOUTH OF THE WARM FRONT WILL BE SOUTH AND SOUTHEAST AT 10 TO 15 MPH
WITH GUSTS TO 20 MPH.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KNUTSVIG
AVIATION...MASEK
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 AM CDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI JUL 5 2013
LOW PRESSURE WILL REMAIN ANCHORED ACROSS THE WRN HIGH PLAINS THIS
AFTERNOON AND TONIGHT. THIS WILL SET UP SOUTHERLY WINDS AS A WARM
FRONT RETREATS ACROSS NRN NEBRASKA. THE HRRR SUGGESTS THE ONGOING
SHOWERS...RAIN AND ISOLATED THUNDERSTORMS ACROSS NWRN NEB...ERN WY
AND SWRN SD WILL CONTINUE MOVING SLOWLY EAST TODAY AFFECTING NRN
NEB ALONG AND NORTH OF A WARM FRONT EXPECTED TO REMAIN ALONG
HIGHWAY 20 FOR THE MOST PART. SOUTH OF THIS FRONT TEMPERATURES
COULD RISE INTO THE MID 90S WHILE AREAS NORTH OF THE FRONT REMAIN
IN THE UPPER 80S...PERHAPS COOLER DEPENDING ON THE OUTCOME OF THE
RAIN WHICH MOST MODELS SHOW DECAYING IN THE STABLE NERN QUADRANT
OF THE H500MB UPPER LEVEL RIDGE.
DIURNALLY DRIVEN ISOLATED THUNDERSTORMS MIGHT DEVELOP SOUTH OF THE
WARM FRONT WITH THE STRONG HEATING. THESE STORMS SHOULD BE ELEVATED
AS DEW POINTS AT THE SFC REMAIN IN THE LOWER 50S. NO ORGANIZED
SEVERE WEATHER IS EXPECTED WITH ANY STORMS WHICH DEVELOP GIVEN THE
LOW LEVEL MOISTURE PROFILES. STILL ELEVATED STORMS MIGHT PRODUCE
STRONG OR SEVERE WIND GUSTS GIVEN THE RELATIVELY WEAK WINDS ALOFT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI JUL 5 2013
THE BIG NEWS IS THAT MOISTURE WILL BE ON THE INCREASE DURING THE
BEGINNING OF THIS PERIOD. PRECIPITABLE WATER VALUES HAVE BEEN
RUNNING AROUND 0.6 TO 0.8 INCHES LATELY...BUT WILL INCREASE TO
OVER 1.25 INCHES FOR SATURDAY AND SUNDAY. THE AVERAGE FOR THIS
TIME OF YEAR IS 1.08 INCHES...SO THIS WEEKENDS PWATS WILL BE IN
THE 75TH PERCENTILE COMPARED TO CLIMATOLOGY.
THE UPPER RIDGE WILL BEGIN TO BREAK DOWN BY SATURDAY...WITH A MORE
ZONAL FLOW SETTING UP AND WEAK DISTURBANCES IN THE FLOW EXPECTED.
WITH THE INCREASED MOISTURE...INSTABILITY WILL EXIST ACROSS THE
REGION ON SATURDAY AND SUNDAY. THE FOCUS FOR THUNDERSTORMS WILL BE
ALONG A FRONTAL BOUNDARY THAT WILL EXIST ACROSS THE NORTHWESTERN
FORECAST AREA ON SATURDAY. CAPE LOOKS TO BE AROUND 2000-3000 J/KG IN
THE NORTH SATURDAY NIGHT...WITH 0-6 KM SHEAR RUNNING MAINLY AROUND
30 KTS WITH THE NW APPROACHING 40 KTS. SOME SEVERE STORMS WILL BE
POSSIBLE...WITH THE BEST CHANCE IN THE NORTH SATURDAY NIGHT. ON
SUNDAY...THE FRONT MAKES SOME PROGRESS SOUTH...FOCUSING THE
AFTERNOON THUNDERSTORM ACTIVITY IN THAT AREA. HOWEVER...MODELS
INDICATE THAT THERE MAY BE SOME ACTIVITY MOVING OFF THE HIGHER
TERRAIN OF WYOMING AND INTO NEBRASKA OVERNIGHT SUNDAY NIGHT. CAPES
WILL GENERALLY RUN 1500-2500 J/KG...WITH THE BEST DEEP SHEAR IN THE
NORTHWEST AROUND 40 KTS YIELDING THE BEST CHANCE FOR SEVERE WEATHER
IN THAT AREA. TEMPERATURES WILL BE IN THE LOW TO MID 90S NORTH TO
NEAR 100 SOUTH ON SATURDAY. ON SUNDAY TEMPS WILL COOL A BIT TO THE
UPPER 80S TO LOW 90S IN MOST AREAS...EXCEPT SOME UPPER 90S ARE
EXPECTED IN THE FAR SOUTH.
NEXT WEEK...AN UPPER LEVEL WAVE WILL MOVE THROUGH THE DAKOTAS EARLY
IN THE WEEK...FOLLOWED BY UPPER RIDGING OVER THE REGION TOWARD THE
END OF THE WEEK. THE PWATS STAY RATHER HIGH THROUGH MID WEEK...
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 619 AM CDT FRI JUL 5 2013
VFR IS GENERALLY EXPECTED TODAY AND TONIGHT. THE ONGOING UPPER
LEVEL DISTURBANCE ACROSS ERN WY/NCNTL COLO IS EXPECTED TO MOVE
EAST THROUGH WRN AND NCNTL NEB TODAY THROUGH EARLY THIS EVENING. THE
MODEL CONCENSUS SUGGESTS ISOLATED SHOWERS AND THUNDERSTORMS WILL
TRAVERSE THE FCST AREA. GIVEN THAT MODEST INSTABILITY DEVELOPS
THIS AFTERNOON...SOME THUNDERSTORMS COULD BECOME STRONG OR SEVERE
AND PRODUCE WIND DAMAGE.
&&
.FIRE WEATHER...
ISSUED AT 315 AM CDT FRI JUL 5 2013
RELATIVE HUMIDITY FALLS TO BETWEEN 20 AND 30 PERCENT THIS AFTERNOON.
ALTHOUGH FUEL STATUS IS NEGATIVE FOR FIRE GROWTH...ONE WILD FIRE
DEVELOPED NEAR ROSCOE THURSDAY AFTERNOON SUGGESTING FUELS MAY BE
FAVORABLE IN SOME AREAS. THE AREA CONCERN FOR WILD FIRES IS WHERE
WINDS WILL BE STRONGEST AND THIS WOULD BE SOUTH OF A WARM FRONT FCST
TO BE ALONG OR NEAR HIGHWAY 20. ISOLATED THUNDERSTORMS ARE POSSIBLE
THIS AFTERNOON BUT MAINLY ALONG AND NORTH OF THE WARM FRONT. WINDS
SOUTH OF THE WARM FRONT WILL BE SOUTH AND SOUTHEAST AT 10 TO 15 MPH
WITH GUSTS TO 20 MPH.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KNUTSVIG
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
315 AM CDT FRI JUL 5 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT FRI JUL 5 2013
LOW PRESSURE WILL REMAIN ANCHORED ACROSS THE WRN HIGH PLAINS THIS
AFTERNOON AND TONIGHT. THIS WILL SET UP SOUTHERLY WINDS AS A WARM
FRONT RETREATS ACROSS NRN NEBRASKA. THE HRRR SUGGESTS THE ONGOING
SHOWERS...RAIN AND ISOLATED THUNDERSTORMS ACROSS NWRN NEB...ERN WY
AND SWRN SD WILL CONTINUE MOVING SLOWLY EAST TODAY AFFECTING NRN
NEB ALONG AND NORTH OF A WARM FRONT EXPECTED TO REMAIN ALONG
HIGHWAY 20 FOR THE MOST PART. SOUTH OF THIS FRONT TEMPERATURES
COULD RISE INTO THE MID 90S WHILE AREAS NORTH OF THE FRONT REMAIN
IN THE UPPER 80S...PERHAPS COOLER DEPENDING ON THE OUTCOME OF THE
RAIN WHICH MOST MODELS SHOW DECAYING IN THE STABLE NERN QUADRANT
OF THE H500MB UPPER LEVEL RIDGE.
DIURNALLY DRIVEN ISOLATED THUNDERSTORMS MIGHT DEVELOP SOUTH OF THE
WARM FRONT WITH THE STRONG HEATING. THESE STORMS SHOULD BE ELEVATED
AS DEW POINTS AT THE SFC REMAIN IN THE LOWER 50S. NO ORGANIZED
SEVERE WEATHER IS EXPECTED WITH ANY STORMS WHICH DEVELOP GIVEN THE
LOW LEVEL MOISTURE PROFILES. STILL ELEVATED STORMS MIGHT PRODUCE
STRONG OR SEVERE WIND GUSTS GIVEN THE RELATIVELY WEAK WINDS ALOFT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 315 AM CDT FRI JUL 5 2013
THE BIG NEWS IS THAT MOISTURE WILL BE ON THE INCREASE DURING THE
BEGINNING OF THIS PERIOD. PRECIPITABLE WATER VALUES HAVE BEEN
RUNNING AROUND 0.6 TO 0.8 INCHES LATELY...BUT WILL INCREASE TO
OVER 1.25 INCHES FOR SATURDAY AND SUNDAY. THE AVERAGE FOR THIS
TIME OF YEAR IS 1.08 INCHES...SO THIS WEEKENDS PWATS WILL BE IN
THE 75TH PERCENTILE COMPARED TO CLIMATOLOGY.
THE UPPER RIDGE WILL BEGIN TO BREAK DOWN BY SATURDAY...WITH A MORE
ZONAL FLOW SETTING UP AND WEAK DISTURBANCES IN THE FLOW EXPECTED.
WITH THE INCREASED MOISTURE...INSTABILITY WILL EXIST ACROSS THE
REGION ON SATURDAY AND SUNDAY. THE FOCUS FOR THUNDERSTORMS WILL BE
ALONG A FRONTAL BOUNDARY THAT WILL EXIST ACROSS THE NORTHWESTERN
FORECAST AREA ON SATURDAY. CAPE LOOKS TO BE AROUND 2000-3000 J/KG IN
THE NORTH SATURDAY NIGHT...WITH 0-6 KM SHEAR RUNNING MAINLY AROUND
30 KTS WITH THE NW APPROACHING 40 KTS. SOME SEVERE STORMS WILL BE
POSSIBLE...WITH THE BEST CHANCE IN THE NORTH SATURDAY NIGHT. ON
SUNDAY...THE FRONT MAKES SOME PROGRESS SOUTH...FOCUSING THE
AFTERNOON THUNDERSTORM ACTIVITY IN THAT AREA. HOWEVER...MODELS
INDICATE THAT THERE MAY BE SOME ACTIVITY MOVING OFF THE HIGHER
TERRAIN OF WYOMING AND INTO NEBRASKA OVERNIGHT SUNDAY NIGHT. CAPES
WILL GENERALLY RUN 1500-2500 J/KG...WITH THE BEST DEEP SHEAR IN THE
NORTHWEST AROUND 40 KTS YIELDING THE BEST CHANCE FOR SEVERE WEATHER
IN THAT AREA. TEMPERATURES WILL BE IN THE LOW TO MID 90S NORTH TO
NEAR 100 SOUTH ON SATURDAY. ON SUNDAY TEMPS WILL COOL A BIT TO THE
UPPER 80S TO LOW 90S IN MOST AREAS...EXCEPT SOME UPPER 90S ARE
EXPECTED IN THE FAR SOUTH.
NEXT WEEK...AN UPPER LEVEL WAVE WILL MOVE THROUGH THE DAKOTAS EARLY
IN THE WEEK...FOLLOWED BY UPPER RIDGING OVER THE REGION TOWARD THE
END OF THE WEEK. THE PWATS STAY RATHER HIGH THROUGH MID WEEK...
HELPING KEEP THE CHANCE FOR THUNDERSTORMS IN THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1142 PM CDT THU JUL 4 2013
FOR THE REMAINDER OF TONIGHT...SOME SCATTERED HIGH CLOUDINESS WILL
STREAM INTO WESTERN AND NORTH CENTRAL NEBRASKA FROM WYOMING. CLOUD
COVER WILL DIMINISH AS YOU HEAD FARTHER EAST INTO CENTRAL
NEBRASKA. FOR FRIDAY...LOOK FOR MID AND HIGH CLOUDS TO INCREASE
THROUGHOUT THE DAY...WITH BROKEN TO OVERCAST SKIES POSSIBLE BY
FRIDAY AFTERNOON. CIGS WILL RANGE FROM 12000 TO 20000 FT AGL AND
ARE EXPECTED TO PERSIST THROUGH FRIDAY EVENING. THERE IS A SMALL
THREAT FOR SHOWERS AND THUNDERSTORMS IN THE PANHANDLE AND WESTERN
NEBRASKA FRIDAY AFTERNOON AND EVENING. COVERAGE WILL BE ISOLATED
AT BEST FOR THE KVTN AND KLBF TERMINALS...SO WILL FORGO MENTION IN
THE 06Z TAF.
&&
.FIRE WEATHER...
ISSUED AT 315 AM CDT FRI JUL 5 2013
RELATIVE HUMIDITY FALLS TO BETWEEN 20 AND 30 PERCENT THIS AFTERNOON.
ALTHOUGH FUEL STATUS IS NEGATIVE FOR FIRE GROWTH...ONE WILD FIRE
DEVELOPED NEAR ROSCOE THURSDAY AFTERNOON SUGGESTING FUELS MAY BE
FAVORABLE IN SOME AREAS. THE AREA CONCERN FOR WILD FIRES IS WHERE
WINDS WILL BE STRONGEST AND THIS WOULD BE SOUTH OF A WARM FRONT FCST
TO BE ALONG OR NEAR HIGHWAY 20. ISOLATED THUNDERSTORMS ARE POSSIBLE
THIS AFTERNOON BUT MAINLY ALONG AND NORTH OF THE WARM FRONT. WINDS
SOUTH OF THE WARM FRONT WILL BE SOUTH AND SOUTHEAST AT 10 TO 15 MPH
WITH GUSTS TO 20 MPH.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...KNUTSVIG
AVIATION...CLB
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 PM MDT THU JUL 4 2013
.AVIATION...
06Z TAF CYCLE
CONVECTIVE ACTIVITY CONTINUING OVER PORTIONS OF NORTHERN AND CENTRAL
NM LATE TONIGHT. SHOWERS AND ISOLD THUNDERSTORMS WILL CONTINUE FOR THE
NEXT SEVERAL HOURS BEFORE GRADUALLY DISSPATING BY EARLY MORNING. WEAK
WAVE ROUNDING THE TOP OF THE UPPER HIGH WILL MOVE SEWD THROUGH NM
FRIDAY...LIKELY GETTING CONVECTION GOING OVER WRN AND CENTRAL NM
LATE FRIDAY MORNING...WITH SCT -TSRA MOST LOCATIONS BY EARLY
AFTERNOON. WEST/SW BREEZES WILL ALSO BE ON THE INCREASE FRIDAY
MORNING AS LEE SIDE TROUGHING STRENGTHENS OVER ERN CO.
33
.PREV DISCUSSION...325 PM MDT THU JUL 4 2013...
STORMS ARE A LITTLE SLOWER TO START TODAY THAN YESTERDAY. LAPS
ANALYSIS NOT SHOWING AS MUCH INSTABILITY AS YESTERDAY...AND THERE
DOES NOT APPEAR TO BE A NOSE OF A JET MOVING MOVING INTO THE
STATE...THOUGH SOME MODERATE NORTHERLY FLOW CONTINUES. SEVERE
WEATHER IS NOT LOOKING AS LIKELY AS YESTERDAY DUE TO THE ABOVE
REASONS...THOUGH THERE COULD STILL BE A STORM OR TWO THAT PRODUCES
LARGE HAIL AND DAMAGING WINDS. LATEST RUN OF THE HRRR SUGGESTS
MOST OF THE ACTIVITY THROUGH THE EVENING WILL REMAIN ACROSS THE
WEST...NEAR THE AZ/NM BORDER...WITH LESSER AMOUNTS OF ACTIVITY
ALONG AND EAST OF THE CENTRAL MOUNTAIN CHAIN. THE HRRR ALSO
SUGGESTS SOME ACTIVITY MOVING INTO NORTHWEST NM AFTER
MIDNIGHT...THOUGH NOT CONFIDENT THIS WILL HAPPEN. FOCUSED POPS
MAINLY ACROSS WC/SW AREAS...THOUGH CONTINUED SOME CHANCE POPS
ALONG THE CENTRAL MTN CHAIN WHERE STORMS ARE JUST INCREASING IN
COVERAGE.
THE UPPER HIGH WILL INCH EASTWARD FRIDAY...CENTERING OVER EASTERN
AZ. THE NAM HAS BEEN VERY PERSISTENT OVER THE LAST TWO DAYS THAT
DESPITE SOME WEAK W/NW FLOW BRINGING IN SOME DRIER AIR ACROSS NW
NM...SHOWERS AND THUNDERSTORMS WILL BE ABUNDANT. OTHER MODELS ARE
NOT AS BULLISH ON QPF...THOUGH SEEMINGLY...THE NAM HAS BEEN
PERFORMING BETTER THAN THE OTHER MODELS AS OF LATE REGARDING
CONVECTION. THERE ALSO APPEARS TO BE A WEAK DISTURBANCE PERHAPS
ROUNDING THE HIGH. THUS...KNOCKED POPS UP A BIT MORE FOR
FRIDAY...AND SPREAD THEM EASTWARD A BIT AS WELL. STEERING FLOW
SHOULD TAKE STORMS A LITTLE MORE TO THE SOUTHEAST...THOUGH OVERALL
IT WILL BE LIGHTER.
BY SATURDAY...THE UPPER HIGH WILL BE SQUARE OVER NM. ENOUGH MOISTURE
WILL REMAIN IN PLACE TO KEEP THE AREA CONVECTIVELY ACTIVE. STEERING
FLOW WILL BE WEAK...THROUGH STORMS MAY NOT BE AS POTENT GIVEN THE
UPPER HIGH OVERHEAD. ON SUNDAY...THE CANADIAN AND THE ECMWF SHIFT
THE CENTER OF THE HIGH EASTWARD OVER OKLAHOMA...ALLOWING FOR WHAT
APPEARS TO BE A MORE TRADITIONAL PLUME OF MONSOON MOISTURE OVER
WESTERN/CENTRAL NM. MEANWHILE...THE NAM AND THE GFS KEEP THE CENTER
OF THE HIGH OVER NM...LIMITING ANY NORTHWARD MOVING MOISTURE.
REGARDLESS...SHOULD REMAIN ACTIVE...THOUGH WILL BE MORESO IF THE
HIGH CAN SHIFT EAST.
EARLY NEXT WEEK...STILL LOOKS LIKE THE HIGH WILL WOBBLE AROUND
SOME...AND MODELS STILL ARE AT ODDS WITH WHERE IT WILL END UP. AN
EASTERLY WAVE STILL LOOKS LIKE IT WILL MOVE ACROSS MEXICO...AND
IMPACTS WILL REMAIN SOUTH OF THE AREA. BY WEDNESDAY...A BACK DOOR
COLD FRONT MAY HELP SPARK ADDITIONAL STORMS ACROSS THE NORTHEAST.
34
.FIRE WEATHER...
FINALLY A SHIFT IN THE LARGE SCALE PATTERN IS UNDERWAY...AS THE
PERSISTENT UPPER LEVEL RIDGE TO THE WEST HAS BECOME LESS AMPLIFIED
AND THE CENTER HAS MOVED TO THE SOUTH...CURRENTLY POSITIONED OVER
WESTERN ARIZONA. UPPER LOW STILL OVER MISSOURI. GRADIENT ACROSS
NEW MEXICO HAS RELAXED A BIT BUT STILL A 60 KNOT UPPER JET OVER
EASTERN NEW MEXICO. THUNDERSTORMS THIS AFTERNOON HAVE BEEN MORE
NUMEROUS ACROSS WESTERN ZONES AND A LITTLE SLOWER TO FIRE OVER THE
NORTHERN HIGH TERRAIN. STILL EXPECTING COVERAGE TO INCREASE OVER
THE NEXT COUPLE OF HOURS. STEERING FLOW IS STILL NORTH TO SOUTH
WITH MAGNITUDES JUST A BIT SLOWER THAN YESTERDAY. CENTRAL AND
SOUTHWEST AREAS TO BE FAVORED WITH NOT MUCH ACTIVITY ACROSS THE
EAST.
THE UPPER HIGH WILL CONTINUE TO GRADUALLY SHIFT TO THE EAST OVER THE
NEXT SEVERAL DAYS...AND WITH LITTLE SCOURING OF MOISTURE DAILY
ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THOUGH THE STEERING
FLOW WILL SHIFT FROM DAY TO DAY.
BY LATE FRIDAY THE HIGH WILL BE CENTERED OVER EXTREME WESTERN NEW
MEXICO AND WHILE THE UPPER LOW REMAINS OVER MISSOURI...THE UPPER
LEVEL GRADIENT OVER NEW MEXICO WILL BE WEAKER YET...WITH A NORTHWEST
TO SOUTHEAST ORIENTATION. THIS SHIFT...ALONG WITH A WEAK
DISTURBANCE ROUNDING THE TOP OF THE RIDGE SHOULD RESULT IN INCREASED
COVERAGE OF WETTING RAIN ACROSS THE NORTHEAST...WITH SIMILAR
DISTRIBUTIONS TO TODAY OVER THE REMAINDER OF THE AREA. FOR SATURDAY
AND SUNDAY... THE HIGH IS CENTERED OVER NEW MEXICO WITH MOISTURE
RECYCLING IN PLACE. THUS...THE HIGHER TERRAIN WILL BE FAVORED FOR
SLOWER MOVING WETTING RAIN...WITH THE NORTHWEST PLATEAU...CENTRAL
VALLEYS AND EXTREME EASTERN PLAINS SEEING THE LEAST ACTION.
EXTENDED MODELS CONTINUE TO SHIFT THE UPPER HIGH TO THE EAST WHILE
ELONGATING IT TO COVER MUCH OF THE SOUTHWEST AND SOUTH CENTRAL
STATES. DRIER AND MORE UNSTABLE CONDITIONS WITH A HIGH HAINES OF 6
ARE EXPECTED ACROSS THE NORTHWEST MONDAY THROUGH WEDNESDAY...WITH
MAINLY HIGH TERRAIN SLOW MOVING SHOWERS AND THUNDERSTORMS PRODUCING
WETTING RAIN WITH SMALL FOOTPRINTS.
RH RECOVERIES TO BE MOSTLY GOOD TO EXCELLENT THROUGH THE
PERIOD...EXCEPT FOR FAIR VALUES ACROSS THE NORTHWEST PLATEAU AND
HIGHLANDS. VENTILATION TO BE MAINLY GOOD TO EXCELLENT THROUGH THE
PERIOD...EXCEPT FOR SOME FAIR VALUES IN THE CENTRAL VALLEYS AND
NORTHERN HIGH TERRAIN MONDAY THROUGH WEDNESDAY.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1113 PM EDT SAT JUL 6 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EAST COAST COMBINED WITH A MID LEVEL
LOW OVER THE MIDWEST WILL KEEP A SOUTHERLY FLOW OF WARM AND MOIST
AIR THROUGH THE REMAINDER OF THE WEEKEND WITH SCATTERED SHOWERS AND
THUNDERSTORMS...ESPECIALLY INLAND FROM THE LAKES. THE UNSETTLED
WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK BEFORE DRIER
AIR FINALLY ARRIVES BY THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
KBUF RADAR SHOWING AN AREA OF LIGHT SHOWERS LIFTING FROM THE
SOUTHERN TIER INTO THE UPPER GENESEE VALLEY WITH A MORE INTENSE
AREA OF SHOWERS WITH EMBEDDED LIGHTENING SHIFTING NORTHEAST ACROSS
FAR SOUTHERN ONTARIO PROVINCE...CENTRAL LAKE ERIE AND INTO NORTHWEST
PA. THESE TWO AREAS WILL BE THE FOCUS FOR ANY RAIN AND THUNDER
OVERNIGHT FOR WESTERN NY. 00Z KBUF RAOB SHOWS A SKINNY CAPE PROFILE
DUE TO THE MODIFIED TROPICAL AIRMASS OVER WESTERN NEW YORK. THERE IS
SOME INSTABILITY FOR THE STORMS OF CENTRAL LAKE ERIE TO WORK WITH.
LATEST SHORT TERM GUIDANCE INCLUDING HRRR AND NAM MODELS SHOW THE
SHOWERS THAT ARE CURRENTLY MOVING INTO THE UPPER GENESEE VALLEY
WILL CONTINUE TO WEAKEN OVER THE NEXT HOUR OR SO. HOWEVER MODELS
SHOW THE ACTIVITY TO OUR WEST OVER LAKE ERIE MAY AT LEAST CLIP
PORTIONS OF WESTERN NY DURING THE OVERNIGHT HOURS. HAVE CONTINUED TO
FEATURE SHOWERS WITH AN CHANCE OF THUNDER IN THE FORECAST OVERNIGHT
ACROSS WESTERN NY WITH A LOWER CHANCE EXTENDING INTO THE FINGER
LAKES AND EASTERN LAKE ONTARIO REGION. ALL OF THIS ACTIVITY IS
LIFTING NORTH OUT OF VERY MOIST AIRMASS OBSERVED WITHIN WATER VAPOR
IMAGERY. MID-LEVEL HIGH PRESSURE OFF THE MID-ATLANTIC COAST AND CUT
OFF LOW PRESSURE ACROSS SOUTHERN ILLINOIS/INDIANA IS CONTINUING TO
ALLOW THIS OPEN CONNECTION OF THE GULF MOISTURE UP INTO THE OHIO
VALLEY.
OTHERWISE...WE HAVE ANOTHER WARM AND HUMID NIGHT...WITH MOISTURE AND
A MODEST FLOW TO KEEP TEMPERATURES IN THE UPPER 60S TO LOWER 70S.
SOME LIGHT FOG IS ALSO POSSIBLE...HOWEVER A MODEST FLOW SHOULD LIMIT
DEVELOPMENT.
ON SUNDAY...THE CUT-OFF LOW OVER SOUTHERN ILLINOIS/INDIANA THIS EVENING
WILL FINALLY START TO LIFT NORTHWARD. MODEL GUIDANCE DIFFERS ON
EXACTLY HOW FAR IT WILL LIFT. REGARDLESS OF THE EXACT TRACK...IT
APPEARS LIKELY THAT IT WILL LIFT A DECENT SLUG OF MOISTURE WITH IT.
ITS CLOSER PROXIMITY WILL ALSO ENHANCE UPPER LEVEL DIFFLUENCE AS THE
500 MB FLOW FANS OUT. BOTH OF THESE FACTORS SHOULD LEAD TO MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS ON SUNDAY...WITH LAKE BREEZE
BOUNDARIES PROVIDING AN ADDITIONAL FOCUS. BECAUSE OF THIS...WILL
CARRY A FAIRLY LARGE AREA OF LIKELY POPS...WITH AN AREA OF CHANCE
POPS DUE TO LAKE SHADOWING NE OF THE LAKES. WITH PRECIPITABLE WATER
VALUES NEAR 2 INCHES...THE THREAT FOR LOCALLY HEAVY RAINS WILL
PERSIST. HOWEVER...700 MB WINDS SHOULD BE STRONGER THAN THEY HAVE
BEEN...RESULTING IN SOME STORM MOTION...WITH TRAINING THE MORE
LIKELY THREAT. ITS ALSO WORTH NOTING THAT WITH A SLIGHTLY MORE
SHEARED WIND PROFILE...SOME STRONG TO POSSIBLY SEVERE THUNDERSTORMS
ARE POSSIBLE. HIGHS ON SUNDAY SHOULD BE JUST A TAD COOLER IN MOST
LOCATIONS...DUE TO THE MORE WIDESPREAD SHOWERS. HOWEVER...THE
STRONGER SW FLOW WILL LEAD TO WARMER TEMPERATURES ALONG THE SOUTH
SHORES OF LAKE ONTARIO.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
THE UPPER TROUGH AND CUTOFF LOW WHICH HAVE BEEN IN PLACE OVER THE
MIDWESTERN STATES WILL BE ACROSS THE NORTH OF THE MID OHIO VALLEY
EARLY SUNDAY NIGHT...MOVING TO SOUTHWESTERN PA BY EARLY MONDAY.
COOLER TEMPERATURES ALOFT ASSOCIATED WITH PASSING UPPER LEVEL TROUGH
WILL ENHANCE INSTABILITY ON SUNDAY NIGHT AND MONDAY AND GENERATE A
FEW MORE SHOWERS AND THUNDERSTORMS.
PRECIPITABLE WATER VALUES THROUGH THE PERIOD WILL RANGE FROM 1.5
INCH TO 1.75 INCH...THUS ANY CONVECTION MAY PRODUCE DOWNPOURS OF
RAIN BUT THERE SHOULD BE SUFFICIENT DIRECTIONAL SHEAR TO KEEP CELLS
FROM TRAINING OVER THE SAME SMALL AREAS ALONG THE STORM TRACKS...
LIMITING THE FLOOD THREAT.
AS THE UPPER TROUGH MOVES TO THE EAST OF THE AREA ON TUESDAY...THERE
WILL BE WEAK RIDGING WHICH SHOULD SUPPRESS THE DEVELOPMENT OF PRECIP
DURING THE EARLY TO MID PARTS OF THE DAY. THERE MAY BE LATE DAY AND
EVENING STORMS MOVING FROM THE WEST AS A SHORT WAVE AND MODEST 30
KNOT 850MB JET ARRIVE FROM THE MIDWESTERN STATES...MAXIMIZING THE
CONVECTIVE CHANCE TUESDAY NIGHT.
TEMPERATURES DURING MONDAY WILL BE CLOSER TO SEASONAL NORMALS...
MAYBE A DEGREE OR TWO BELOW NORMAL IN SPOTS...AS THE UPPER TROUGH
CROSSES THE AREA. WARMER AIR RETURNS FOR TUESDAY WITH ABUNDANT
SUNSHINE AND HIGHS IN THE LOWER TO MIDDLE 80S. LOWS EACH NIGHT WILL
BE IN THE LOWER TO MID 60S ACROSS THE SOUTHERN TIER AND HIGHER
TERRAIN OF THE TUG HILL...AND THE MID TO UPPER 60S ELSEWHERE...EVEN
TO LOW 70S FOR THE URBAN CENTERS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A GENERAL ZONAL FLOW ALOFT AT THE START OF THIS PERIOD WILL
TRANSITION TO A HIGHER AMPLITUDE PATTERN...CHARACTERIZED BY A
DIGGING TROUGH OVER THE GREAT LAKES WHILE A RIDGE BUILDS OUT WEST.
THIS PATTERN SHIFT WILL RESULT IN A TREND TOWARD SLIGHTLY COOLER
TEMPERATURES AND LOWER HUMIDITY AS THE WEEK PROGRESSES.
BY WEDNESDAY...THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL MAINTAIN A LIKELIHOOD OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A LOWERING RAIN CHANCE AS THE DAY AND EVENING
PROGRESS. AS THE AFOREMENTIONED UPPER LEVEL TROUGH SHIFTS EAST
ACROSS QUEBEC AND THE LOWER LAKES ON FRIDAY...TEMPERATURES MAY DROP
TO SLIGHTLY BELOW AVERAGE LEVELS. WHILE THE TROUGH MAY ENHANCE
INSTABILITY...THE LATEST GUIDANCE SUGGESTS THAT THIS SYSTEM WILL BE
STARVED FOR MOISTURE SO WILL HAVE ONLY LOW CHANCE OR SLIGHT CHANCE
POPS FOR FRIDAY AND SATURDAY. MOST OF THE RESULTANT RAIN FROM THIS
WILL BE ASSOCIATED WITH AN OFFSHORE COASTAL SYSTEM AND SURFACE HIGH
PRESSURE WILL DOMINATE THE EASTERN GREAT LAKES TO OHIO VALLEY.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE MOST PART OVERNIGHT. AN AREA OF
SHOWERS AND THUNDERSTORMS APPROACHING THE EASTERN END OF LAKE ERIE
ARE EXPECTED TO SHIFT OVER THE WESTERN TAF SITES WHILE WEAKENING
OVERNIGHT. OUTSIDE OF THIS SHRA/TSRA ACTIVITY...SOME LIGHT FOG IS
POSSIBLE AT EASTERN TAF SITES OVERNIGHT WHERE WINDS WILL FALL OFF
NEAR CALM...WITH IFR CIGS/VIS INTERMITTENTLY AT JHW AFTER THEY
RECEIVED SOME RAINFALL THIS EVENING. CHANCES FOR THUNDERSTORMS WILL
INCREASE AGAIN DURING THE DAY SUNDAY...DUE TO DIURNAL CYCLES.
AS HAS BEEN THE CASE...HEAVY RAIN FROM SHOWERS AND THUNDERSTORMS
WILL BE ABLE TO BRIEFLY LOWER VSBY TO 2SM OR LESS.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH SCATTERED SHOWERS
AND THUNDERSTORMS WITH PERIODS OF MVFR/IFR CONDITIONS.
&&
.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES RELATIVELY LOW THROUGH THE REMAINDER OF THE WEEKEND
AND INTO EARLY NEXT WEEK. EXPECT WINDS TO BE SOUTHWEST MOST OF THE
TIME WITH SOME LOCAL LAKE BREEZES ON LAKE ONTARIO TURNING WINDS
ONSHORE DURING THE AFTERNOONS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...SMITH/APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...SMITH/TMA
MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
813 PM EDT SAT JUL 6 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EAST COAST COMBINED WITH A MID LEVEL
LOW OVER THE MIDWEST WILL KEEP A SOUTHERLY FLOW OF WARM AND MOIST
AIR THROUGH THE REMAINDER OF THE WEEKEND WITH SCATTERED SHOWERS AND
THUNDERSTORMS...ESPECIALLY INLAND FROM THE LAKES. THE UNSETTLED
WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK BEFORE DRIER
AIR FINALLY ARRIVES BY THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
KBUF RADAR THIS EVENING SHOWS A CLUSTER SHOWERS AND THUNDERSTORMS
WORKING NORTHWARD TOWARD THE WESTERN SOUTHERN TIER. THESE ARE MOVING
INTO CHAUTAUQUA AND CATTARAUGUS COUNTIES NEAR 8PM AND WILL PUSH
NORTH INTO SOUTHERN ERIE AND WYOMING COUNTIES CLOSER TO 9-10PM.
UPDATED THE FORECAST GRIDS TO ACCOUNT FOR THESE CURRENT RADAR TRENDS
AND EXTRAPOLATION NORTHWARD. WILL CONTINUE TO MONITOR TO SEE IF
THESE WILL MAKE IT TO METRO BUFFALO AREA AND POINTS NORTHWARD.
MESOANALYSIS FIELDS SHOW MORE STABLE AIRMASS NEAR THE EASTERN END OF
LAKE ERIE WHICH COULD WORK TO DIMINISH ACTIVITY.
FURTHER TO THE WEST AND SOUTH MORE SHOWER AND THUNDERSTORM ACTIVITY
IS OBSERVED ON A REGIONAL RADAR MOSAIC OVER MUCH OF NORTHERN AND
SOUTHERN OHIO. ALTHOUGH THERE ARE SOME MODEL DIFFERENCES...IT
APPEARS THIS ACTIVITY WILL EVENTUALLY MOVE INTO OUR REGION WITH
THE NOSE OF AN INCREASING 700 MB FLOW. NEAR TERM MODEL GUIDANCE
INCLUDING HRRR AND RGEM RUNS SHOW THIS ACTIVITY WILL ARRIVE TOWARD
MIDNIGHT INTO THE EARLY MORNING HOURS. ALL OF THE MENTIONED ACTIVITY
IS LIFTING NORTH OUT OF VERY MOIST AIRMASS OBSERVED WITHIN WATER
VAPOR IMAGERY. MID-LEVEL HIGH PRESSURE OFF THE MID-ATLANTIC COAST AND
CUT OFF LOW PRESSURE ACROSS SOUTHERN ILLINOIS IS CONTINUING TO ALLOW THIS
OPEN CONNECTION OF THE GULF MOISTURE UP INTO THE OHIO VALLEY.
WITH THE HIGH LEVEL OF MOISTURE IN THE ATMOSPHERE /PWATS TO 1.9
INCHES/ THERE WILL BE A CONTINUED THREAT FOR LOCALLY HEAVY RAINFALL
IN ANY STRONGER CELL CORES. 700 MB WINDS ARE FORECAST TO INCREASE TO
AROUND 30 KNOTS LATER TONIGHT...WHICH SHOULD AT LEAST PROVIDE SOME
STORM MOTION TO MITIGATE THE RISK FOR FLOODING. LARGE AREAS OR
TRAINING CELLS WOULD STILL HAVE THE POTENTIAL TO PRODUCE
FLOODING...WITH CONTINUED MENTION IN THE HWO STILL JUSTIFIED.
OUTSIDE OF THE ACTIVITY MOVING INTO THE SOUTHERN TIER...ALL OTHER
SECTIONS OF THE FORECAST AREA FROM THE NIAGARA FRONTIER AND
GENESEE VALLEY EAST TO THE FINGER LAKES AND EAST OF LAKE ONTARIO
ARE RAIN-FREE THIS EVENING.
ON SUNDAY...THE PERSISTENT CUT-OFF LOW WILL FINALLY START TO LIFT
NORTHWARD. MODEL GUIDANCE DIFFERS ON EXACTLY HOW FAR IT WILL LIFT.
REGARDLESS OF THE EXACT TRACK...IT APPEARS LIKELY THAT IT WILL LIFT
A DECENT SLUG OF MOISTURE WITH IT. ITS CLOSER PROXIMITY WILL ALSO
ENHANCE UPPER LEVEL DIFFLUENCE AS THE 500 MB FLOW FANS OUT. BOTH OF
THESE FACTORS SHOULD LEAD TO MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...WITH LAKE BREEZE BOUNDARIES PROVIDING AN
ADDITIONAL FOCUS. BECAUSE OF THIS...WILL CARRY A FAIRLY LARGE AREA
OF LIKELY POPS...WITH AN AREA OF CHANCE POPS DUE TO LAKE SHADOWING
NE OF THE LAKES. WITH PRECIPITABLE WATER VALUES NEAR 2 INCHES...THE
THREAT FOR LOCALLY HEAVY RAINS WILL PERSIST. HOWEVER...700 MB WINDS
SHOULD BE STRONGER THAN THEY HAVE BEEN...RESULTING IN SOME STORM
MOTION...WITH TRAINING THE MORE LIKELY THREAT. ITS ALSO WORTH NOTING
THAT WITH A SLIGHTLY MORE SHEARED WIND PROFILE...SOME STRONG TO
POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE.
OTHERWISE...IT WILL BE ANOTHER WARM NIGHT...WITH MOISTURE AND A
MODEST FLOW LIKELY TO KEEP TEMPERATURES IN THE UPPER 60S TO LOWER
70S. SOME LIGHT FOG IS ALSO POSSIBLE...HOWEVER A MODEST FLOW SHOULD
LIMIT DEVELOPMENT. HIGHS ON SUNDAY SHOULD BE JUST A TAD COOLER IN
MOST LOCATIONS...DUE TO THE MORE WIDESPREAD SHOWERS. HOWEVER...THE
STRONGER SW FLOW WILL LEAD TO WARMER TEMPERATURES ALONG THE SOUTH
SHORES OF LAKE ONTARIO.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
THE UPPER TROUGH AND CUTOFF LOW WHICH HAVE BEEN IN PLACE OVER THE
MIDWESTERN STATES WILL BE ACROSS THE NORTH OF THE MID OHIO VALLEY
EARLY SUNDAY NIGHT...MOVING TO SOUTHWESTERN PA BY EARLY MONDAY.
COOLER TEMPERATURES ALOFT ASSOCIATED WITH PASSING UPPER LEVEL TROUGH
WILL ENHANCE INSTABILITY ON SUNDAY NIGHT AND MONDAY AND GENERATE A
FEW MORE SHOWERS AND THUNDERSTORMS.
PRECIPITABLE WATER VALUES THROUGH THE PERIOD WILL RANGE FROM 1.5
INCH TO 1.75 INCH...THUS ANY CONVECTION MAY PRODUCE DOWNPOURS OF
RAIN BUT THERE SHOULD BE SUFFICIENT DIRECTIONAL SHEAR TO KEEP CELLS
FROM TRAINING OVER THE SAME SMALL AREAS ALONG THE STORM TRACKS...
LIMITING THE FLOOD THREAT.
AS THE UPPER TROUGH MOVES TO THE EAST OF THE AREA ON TUESDAY...THERE
WILL BE WEAK RIDGING WHICH SHOULD SUPPRESS THE DEVELOPMENT OF PRECIP
DURING THE EARLY TO MID PARTS OF THE DAY. THERE MAY BE LATE DAY AND
EVENING STORMS MOVING FROM THE WEST AS A SHORT WAVE AND MODEST 30
KNOT 850MB JET ARRIVE FROM THE MIDWESTERN STATES...MAXIMIZING THE
CONVECTIVE CHANCE TUESDAY NIGHT.
TEMPERATURES DURING MONDAY WILL BE CLOSER TO SEASONAL NORMALS...
MAYBE A DEGREE OR TWO BELOW NORMAL IN SPOTS...AS THE UPPER TROUGH
CROSSES THE AREA. WARMER AIR RETURNS FOR TUESDAY WITH ABUNDANT
SUNSHINE AND HIGHS IN THE LOWER TO MIDDLE 80S. LOWS EACH NIGHT WILL
BE IN THE LOWER TO MID 60S ACROSS THE SOUTHERN TIER AND HIGHER
TERRAIN OF THE TUG HILL...AND THE MID TO UPPER 60S ELSEWHERE...EVEN
TO LOW 70S FOR THE URBAN CENTERS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A GENERAL ZONAL FLOW ALOFT AT THE START OF THIS PERIOD WILL
TRANSITION TO A HIGHER AMPLITUDE PATTERN...CHARACTERIZED BY A
DIGGING TROUGH OVER THE GREAT LAKES WHILE A RIDGE BUILDS OUT WEST.
THIS PATTERN SHIFT WILL RESULT IN A TREND TOWARD SLIGHTLY COOLER
TEMPERATURES AND LOWER HUMIDITY AS THE WEEK PROGRESSES.
BY WEDNESDAY...THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL MAINTAIN A LIKELIHOOD OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A LOWERING RAIN CHANCE AS THE DAY AND EVENING
PROGRESS. AS THE AFOREMENTIONED UPPER LEVEL TROUGH SHIFTS EAST
ACROSS QUEBEC AND THE LOWER LAKES ON FRIDAY...TEMPERATURES MAY DROP
TO SLIGHTLY BELOW AVERAGE LEVELS. WHILE THE TROUGH MAY ENHANCE
INSTABILITY...THE LATEST GUIDANCE SUGGESTS THAT THIS SYSTEM WILL BE
STARVED FOR MOISTURE SO WILL HAVE ONLY LOW CHANCE OR SLIGHT CHANCE
POPS FOR FRIDAY AND SATURDAY. MOST OF THE RESULTANT RAIN FROM THIS
WILL BE ASSOCIATED WITH AN OFFSHORE COASTAL SYSTEM AND SURFACE HIGH
PRESSURE WILL DOMINATE THE EASTERN GREAT LAKES TO OHIO VALLEY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE MOST PART TONIGHT. AN AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS IS SHIFTING NORTH INTO THE
SOUTHERN TIER THIS EVENING WHICH WILL WORK OVER KJHW EARLY IN THE
TAF PERIOD. THESE MAY HOLD TOGETHER LONG ENOUGH TO WORK TOWARD
KBUF/KIAG LATER THIS EVENING. OUTSIDE OF THIS SHRA/TSRA
ACTIVITY...SOME LIGHT FOG IS POSSIBLE AT EASTERN TAF SITES OVERNIGHT
WHERE WINDS WILL FALL OFF NEAR CALM...WITH IFR CIGS POSSIBLE AT JHW
ESPECIALLY AFTER THEY GET SOME RAINFALL THIS EVENING. CHANCES FOR
THUNDERSTORMS WILL INCREASE DURING THE DAY SUNDAY...DUE TO DIURNAL
CYCLES.
AS HAS BEEN THE CASE...HEAVY RAIN FROM SHOWERS AND THUNDERSTORMS
WILL BE ABLE TO BRIEFLY LOWER VSBY TO 2SM OR LESS.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH SCATTERED SHOWERS
AND THUNDERSTORMS WITH PERIODS OF MVFR/IFR CONDITIONS.
&&
.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES RELATIVELY LOW THROUGH THE REMAINDER OF THE WEEKEND
AND INTO EARLY NEXT WEEK. EXPECT WINDS TO BE SOUTHWEST MOST OF THE
TIME WITH SOME LOCAL LAKE BREEZES ON LAKE ONTARIO TURNING WINDS
ONSHORE DURING THE AFTERNOONS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...SMITH/APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL/TMA
MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
729 PM EDT SAT JUL 6 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EAST COAST COMBINED WITH A MID LEVEL
LOW OVER THE MIDWEST WILL KEEP A SOUTHERLY FLOW OF WARM AND MOIST
AIR THROUGH THE REMAINDER OF THE WEEKEND WITH SCATTERED SHOWERS AND
THUNDERSTORMS...ESPECIALLY INLAND FROM THE LAKES. THE UNSETTLED
WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK BEFORE DRIER
AIR FINALLY ARRIVES BY THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
WATER VAPOR IMAGERY SHOWS OUR REGION REMAINS IN A MOIST SOUTHERLY
FLOW...WITH HIGH PRESSURE OFF THE MID-ATLANTIC COAST AND LOW PRESSURE
ACROSS EASTERN MISSOURI. SHOWERS AND POSSIBLY A THUNDERSTORM SHOULD
DEVELOP INLAND OF THE LAKE-BREEZE ACROSS THE SOUTHERN TIER...HOWEVER
SLIGHTLY DRIER AIR SHOULD LIMIT THE AREAL COVERAGE OF THIS
ACTIVITY...MAKING IT MORE SCATTERED IN NATURE.
ANY DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS WILL GRADUALLY TAPER
OFF DURING THE EVENING HOURS...HOWEVER A LARGER AREA OF SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS WESTERN OHIO IS FORECAST TO MOVE
INTO OUR REGION AS IT WEAKENS TONIGHT. ALTHOUGH THERE ARE SOME MODEL
DIFFERENCES...IT APPEARS THESE SHOWERS WILL EVENTUALLY MOVE INTO
OUR REGION WITH THE NOSE OF AN INCREASING 700 MB FLOW. THE GFS/RGEM
HINT AT THIS...THE PAST TWO RUNS OF THE HRRR A BIT LATER IN TIMING
WHICH APPEARS MORE REALISTIC GIVEN THE SLOW MOTION OF THE FEATURE.
EXPECT ASSOCIATED SHOWERS AND THUNDERSTORMS TO MOVE FROM W-E LATE
THIS EVENING...WITH THESE LIKELY TO WEAKEN AS THEY MOVE FURTHER
NORTH FROM THE UPPER LEVEL SUPPORT LATER TONIGHT.
THE 12Z BUFFALO SOUNDING HAD A PRECIPITABLE WATER VALUE OF 1.50
INCHES...HOWEVER SOUNDINGS JUST UPSTREAM IN PITTSBURGH AND
CINCINNATI ARE APPROACHING 2 INCHES. THE RESULT WILL BE A
CONTINUED THREAT FOR LOCALLY HEAVY RAINFALL IN ANY STORMS WHICH DO
DEVELOP. 700 MB WINDS ARE FORECAST TO INCREASE TO AROUND 30 KNOTS
LATER TONIGHT...WHICH SHOULD AT LEAST PROVIDE SOME STORM MOTION TO
MITIGATE THE RISK FOR FLOODING. LARGE AREAS OR TRAINING CELLS
WOULD STILL HAVE THE POTENTIAL TO PRODUCE FLOODING...WITH
CONTINUED MENTION IN THE HWO STILL JUSTIFIED.
ON SUNDAY...THE PERSISTENT CUT-OFF LOW WILL FINALLY START TO LIFT
NORTHWARD. MODEL GUIDANCE DIFFERS ON EXACTLY HOW FAR IT WILL LIFT.
REGARDLESS OF THE EXACT TRACK...IT APPEARS LIKELY THAT IT WILL LIFT
A DECENT SLUG OF MOISTURE WITH IT. ITS CLOSER PROXIMITY WILL ALSO
ENHANCE UPPER LEVEL DIFFLUENCE AS THE 500 MB FLOW FANS OUT. BOTH OF
THESE FACTORS SHOULD LEAD TO MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS ON SUNDAY...WITH LAKE BREEZE BOUNDARIES PROVIDING AN
ADDITIONAL FOCUS. BECAUSE OF THIS...WILL CARRY A FAIRLY LARGE AREA
OF LIKELY POPS...WITH AN AREA OF CHANCE POPS DUE TO LAKE SHADOWING
NE OF THE LAKES. WITH PRECIPITABLE WATER VALUES NEAR 2 INCHES...THE
THREAT FOR LOCALLY HEAVY RAINS WILL PERSIST. HOWEVER...700 MB WINDS
SHOULD BE STRONGER THAN THEY HAVE BEEN...RESULTING IN SOME STORM
MOTION...WITH TRAINING THE MORE LIKELY THREAT. ITS ALSO WORTH NOTING
THAT WITH A SLIGHTLY MORE SHEARED WIND PROFILE...SOME STRONG TO
POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE.
OTHERWISE...IT WILL BE ANOTHER WARM NIGHT...WITH MOISTURE AND A
MODEST FLOW LIKELY TO KEEP TEMPERATURES IN THE UPPER 60S TO LOWER
70S. SOME LIGHT FOG IS ALSO POSSIBLE...HOWEVER A MODEST FLOW SHOULD
LIMIT DEVELOPMENT. HIGHS ON SUNDAY SHOULD BE JUST A TAD COOLER IN
MOST LOCATIONS...DUE TO THE MORE WIDESPREAD SHOWERS. HOWEVER...THE
STRONGER SW FLOW WILL LEAD TO WARMER TEMPERATURES ALONG THE SOUTH
SHORES OF LAKE ONTARIO.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
THE UPPER TROUGH AND CUTOFF LOW WHICH HAVE BEEN IN PLACE OVER THE
MIDWESTERN STATES WILL BE ACROSS THE NORTH OF THE MID OHIO VALLEY
EARLY SUNDAY NIGHT...MOVING TO SOUTHWESTERN PA BY EARLY MONDAY.
COOLER TEMPERATURES ALOFT ASSOCIATED WITH PASSING UPPER LEVEL TROUGH
WILL ENHANCE INSTABILITY ON SUNDAY NIGHT AND MONDAY AND GENERATE A
FEW MORE SHOWERS AND THUNDERSTORMS.
PRECIPITABLE WATER VALUES THROUGH THE PERIOD WILL RANGE FROM 1.5
INCH TO 1.75 INCH...THUS ANY CONVECTION MAY PRODUCE DOWNPOURS OF
RAIN BUT THERE SHOULD BE SUFFICIENT DIRECTIONAL SHEAR TO KEEP CELLS
FROM TRAINING OVER THE SAME SMALL AREAS ALONG THE STORM TRACKS...
LIMITING THE FLOOD THREAT.
AS THE UPPER TROUGH MOVES TO THE EAST OF THE AREA ON TUESDAY...THERE
WILL BE WEAK RIDGING WHICH SHOULD SUPPRESS THE DEVELOPMENT OF PRECIP
DURING THE EARLY TO MID PARTS OF THE DAY. THERE MAY BE LATE DAY AND
EVENING STORMS MOVING FROM THE WEST AS A SHORT WAVE AND MODEST 30
KNOT 850MB JET ARRIVE FROM THE MIDWESTERN STATES...MAXIMIZING THE
CONVECTIVE CHANCE TUESDAY NIGHT.
TEMPERATURES DURING MONDAY WILL BE CLOSER TO SEASONAL NORMALS...
MAYBE A DEGREE OR TWO BELOW NORMAL IN SPOTS...AS THE UPPER TROUGH
CROSSES THE AREA. WARMER AIR RETURNS FOR TUESDAY WITH ABUNDANT
SUNSHINE AND HIGHS IN THE LOWER TO MIDDLE 80S. LOWS EACH NIGHT WILL
BE IN THE LOWER TO MID 60S ACROSS THE SOUTHERN TIER AND HIGHER
TERRAIN OF THE TUG HILL...AND THE MID TO UPPER 60S ELSEWHERE...EVEN
TO LOW 70S FOR THE URBAN CENTERS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A GENERAL ZONAL FLOW ALOFT AT THE START OF THIS PERIOD WILL
TRANSITION TO A HIGHER AMPLITUDE PATTERN...CHARACTERIZED BY A
DIGGING TROUGH OVER THE GREAT LAKES WHILE A RIDGE BUILDS OUT WEST.
THIS PATTERN SHIFT WILL RESULT IN A TREND TOWARD SLIGHTLY COOLER
TEMPERATURES AND LOWER HUMIDITY AS THE WEEK PROGRESSES.
BY WEDNESDAY...THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL MAINTAIN A LIKELIHOOD OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A LOWERING RAIN CHANCE AS THE DAY AND EVENING
PROGRESS. AS THE AFOREMENTIONED UPPER LEVEL TROUGH SHIFTS EAST
ACROSS QUEBEC AND THE LOWER LAKES ON FRIDAY...TEMPERATURES MAY DROP
TO SLIGHTLY BELOW AVERAGE LEVELS. WHILE THE TROUGH MAY ENHANCE
INSTABILITY...THE LATEST GUIDANCE SUGGESTS THAT THIS SYSTEM WILL BE
STARVED FOR MOISTURE SO WILL HAVE ONLY LOW CHANCE OR SLIGHT CHANCE
POPS FOR FRIDAY AND SATURDAY. MOST OF THE RESULTANT RAIN FROM THIS
WILL BE ASSOCIATED WITH AN OFFSHORE COASTAL SYSTEM AND SURFACE HIGH
PRESSURE WILL DOMINATE THE EASTERN GREAT LAKES TO OHIO VALLEY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL FOR THE MOST PART TONIGHT. AN AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS MAY DEVELOP OVERNIGHT AS A
SOUTHERN STREAM SHORTWAVE LIFTS INTO THE REGION. CONFIDENCE IN
TIMING AND LOCATION IS LOW. SOME LIGHT FOG IS POSSIBLE AT EASTERN
TAF SITES WHERE WINDS WILL BE LESS...WITH IFR CIGS POSSIBLE AT JHW.
CHANCES FOR THUNDERSTORMS WILL INCREASE DURING THE DAY SUNDAY...DUE
TO DIURNAL CYCLES.
AS HAS BEEN THE CASE...HEAVY RAIN FROM SHOWERS AND THUNDERSTORMS
WILL BE ABLE TO BRIEFLY LOWER VSBY TO 2SM OR LESS.
OUTLOOK...
SUNDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH SCATTERED SHOWERS
AND THUNDERSTORMS WITH PERIODS OF MVFR/IFR CONDITIONS.
&&
.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES RELATIVELY LOW THROUGH THE REMAINDER OF THE WEEKEND
AND INTO EARLY NEXT WEEK. EXPECT WINDS TO BE SOUTHWEST MOST OF THE
TIME WITH SOME LOCAL LAKE BREEZES ON LAKE ONTARIO TURNING WINDS
ONSHORE DURING THE AFTERNOONS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL/TMA
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
201 PM EDT FRI JUL 5 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL MAINTAIN A
SOUTHERLY FLOW OF WARM AND VERY HUMID AIR OVER OUR REGION THROUGH
THE WEEKEND. THUNDERSTORMS THAT DEVELOP WITHIN THIS HUMID AIRMASS
WILL BE CAPABLE OF PRODUCING VERY HEAVY RAIN AND GUSTY WINDS...BUT
THERE WILL BE FREQUENT RAINFREE PERIODS AS WELL.
&&
.NEAR TERM /THROUGH SATURDAY/...
NUMEROUS SHOWERS ARE DEVELOPING IN THE UNSTABLE AIRMASS WITH ABOUT
40 KTS OF SHEAR OVER MUCH OF WESTERN AND CENTRAL NY...ENOUGH FOR
SOME WEAK SUPERCELL DEVELOPMENT AT TIMES. EXPECT STORMS TO
CONTINUE TO DEVELOP AS A 60 KT 500MB JET PASSES OVERHEAD PER LATEST
AMDAR DATA AND RAP ANALYSIS...WITH STRONGEST STORMS MOVING OFF TO
THE NORTHEAST EARLY THIS AFTERNOON. THERE IS LESS SHEAR AND
STABILITY FURTHER UPSTREAM OVER CENTRAL LAKE ERIE/NW PA...SO EXPECT
A LOWER THREAT FOR ANY SEVERE WEATHER DEVELOPMENT LATE TODAY. AN
ISOLATED THREAT CONTINUES FOR FLOODING...ALTHOUGH THIS THREAT
APPEARS TO BE DIMINISHING WITH TIME. HOWEVER...WITH PLENTY OF
DAYTIME HEATING LEFT...WILL HAVE TO WATCH FOR THE POSSIBILITY OF
TRAINING CELLS.
LATER THIS EVENING...EXPECT A DIMINISHING TREND TO CONVECTION AS
SHORTWAVE TROUGH MOVES OFF TO THE NORTHEAST AND DAYTIME HEATING
WANES. WILL FORECAST A LULL IN RAIN POTENTIAL LATER TONIGHT INTO
SATURDAY MORNING.
ON SATURDAY...WILL AGAIN HAVE TO CONTEND WITH ABUNDANT MOISTURE AS
THE BLOCKED UPPER LEVEL PATTERN CONTINUES TO FORCE A PLUME OF
MOISTURE NORTHWARD FROM THE GULF ACROSS THE EASTERN GREAT LAKES
REGION. WITH THE UPPER LEVEL FLOW A BIT MORE OUT OF THE WEST
INSTEAD OF SW...EXPECT STORM DEVELOPMENT TO BE SUPPRESSED A BIT TO
THE SOUTH/SOUTHEAST COMPARED TO TODAY/FRIDAY...WITH RENEWED
DEVELOPMENT ALONG THE LAKE ERIE BREEZE BOUNDARY AND INTO THE INLAND
SOUTHERN TIER AND PORTIONS OF THE GENESEE VALLEY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
THE UNSETTLED PATTERN WILL CONTINUE THROUGH THE SHORT TERM AS A MID
LEVEL CUTOFF LOW DRIFTS SLOWLY FROM THE MID MISSISSIPPI VALLEY TO
THE OHIO VALLEY THROUGH THE PERIOD. A STRONG BERMUDA HIGH WILL ALSO
REMAIN IN PLACE...WITH DEEP SOUTHERLY FLOW BETWEEN THESE TWO
FEATURES KEEPING A FEED OF DEEP TROPICAL MOISTURE FROM THE GULF OF
MEXICO FLOWING NORTHWARD INTO THE REGION. NUMEROUS LOW AMPLITUDE AND
DIFFICULT TO TIME SHORTWAVES WILL PROPAGATE AROUND THE WESTERN
PERIPHERY OF THE BERMUDA HIGH THROUGH THE PERIOD AND SUPPORT
ENHANCED COVERAGE OF SHOWERS AND A FEW THUNDERSTORMS AT TIMES. THIS
WILL BE SUPERIMPOSED ON THE DIURNAL CYCLE...WHICH IN GENERAL WILL
SUPPORT BEST COVERAGE OF SHOWERS DURING THE AFTERNOON AND EARLY
EVENING WITH LESSER COVERAGE DURING THE LATE NIGHT AND EARLY MORNING
HOURS.
SATURDAY EVENING MOST OF THIS ACTIVITY WILL SLOWLY DISSIPATE WITH
THE LOSS OF DAYTIME HEATING. LATE SATURDAY NIGHT ONE OR TWO WEAK
SHORTWAVES WILL AGAIN CROSS THE LOWER LAKES REGION ALONG WITH AN
INCREASE IN DEEP LAYER MOISTURE. THIS MAY PRODUCE A FEW WIDELY
SCATTERED SHOWERS LATE.
BY SUNDAY THE MID LEVEL CUTOFF LOW OVER THE MIDWEST WILL BEGIN TO
OPEN UP AND RE-ENGAGE WITH THE WESTERLIES. THIS WILL SPREAD HEIGHT
FALLS AND DPVA INTO THE LOWER LAKES REGION WHICH WILL SUPPORT AN
INCREASE IN LARGE SCALE ASCENT. THIS WILL AGAIN PRODUCE AT LEAST
SCATTERED SHOWERS AND A FEW THUNDERSTORMS...WITH THE GREATEST
COVERAGE EXPECTED FROM THE SOUTHERN TIER INTO THE FINGER LAKES AND
CENTRAL NY WITH SOME HELP FROM THE DIURNAL CYCLE AND ASSOCIATED
DIFFERENTIAL HEATING BOUNDARIES. SUNDAY NIGHT THE MID LEVEL CUTOFF
WILL CONTINUE TO MAKE HEADWAY EAST AND APPROACH THE REGION. THE
INCREASE IN LARGE SCALE ASCENT MAY KEEP A FEW SHOWERS GOING INTO THE
NIGHT DESPITE THE LOSS OF DAYTIME HEATING.
PWAT THROUGH THE PERIOD WILL RUN CLOSE TO 2 INCHES AT TIMES. THIS
WILL CONTINUE TO SUPPORT A RISK FOR TORRENTIAL DOWNPOURS AND
ASSOCIATED ISOLATED FLOOD RISK FROM ANY THUNDERSTORM WHICH
DEVELOPS...ESPECIALLY IF TRAINING OCCURS ALONG ANY OF THE LOW LEVEL
BOUNDARIES.
IT WILL REMAIN MUGGY THROUGH THE PERIOD WITH WARM OVERNIGHT LOWS AND
HIGHS JUST SLIGHTLY ABOVE AVERAGE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A SLOW IMPROVING TREND IN SENSIBLE WEATHER WILL TAKE PLACE DURING
THE LONG TERM AS THE PATTERN ACROSS NORTH AMERICA EVOLVES. A ZONAL
PATTERN WILL TAKE HOLD ALONG THE US/CANADIAN BORDER WHICH IN TIME
WILL FORCE DEEPER TROPICAL MOISTURE BACK SOUTH AND AWAY FROM THE
REGION. THE BERMUDA HIGH WILL ALSO WEAKEN A LITTLE AND MOVE FARTHER
OFFSHORE...ENDING THE SOUTHERLY PUMP OF DEEP MOISTURE INTO THE
NORTHEAST STATES.
AT THE START OF THE PERIOD MONDAY AND MONDAY NIGHT THE OLD
MIDWEST CUTOFF LOW WILL PASS BY JUST TO THE SOUTH OF THE AREA. THIS
WILL CONTINUE TO SUPPORT A FEW SCATTERED SHOWERS AND THUNDERSTORMS.
BY TUESDAY A WEAK BUBBLE OF HIGH PRESSURE WILL BUILD INTO THE GREAT
LAKES AND PROVIDE A MUCH NEEDED MAINLY DRY DAY.
BY WEDNESDAY BOTH THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL BRING BACK THE CHANCE OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A RETURN TO MAINLY DRY WEATHER.
TEMPERATURES WILL CONTINUE TO RUN A LITTLE ABOVE AVERAGE THROUGH
MOST OF THE PERIOD WITH VERY MUGGY CONDITIONS. THIS WILL IMPROVE BY
THURSDAY WITH A DRIER AND LESS HUMID AIRMASS BUILDING INTO THE
REGION BEHIND A STRONGER COLD FRONT.
LOOKING A LITTLE FARTHER AHEAD...SOME PROMISE IS SEEN FOR A MORE
EXTENDED PERIOD OF DRYING LATER NEXT WEEK THROUGH NEXT WEEKEND AS A
BAROCLINIC ZONE GETS FORCED MAINLY SOUTH OF THE AREA AS A TROUGH
DIGS INTO EASTERN CANADA. THIS WOULD PUT OUR REGION ON THE DRIER AND
LESS HUMID SIDE OF THE BOUNDARY...WITH LOWER RH DAYS GIVING SOILS A
CHANCE TO DRY OUT.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
A MOISTURE LADEN AIRMASS WILL REMAIN IN PLACE ACROSS THE REGION
THROUGH THE TAF PERIOD. A SHORT WAVE TROUGH WILL PUSH EAST ACROSS
CENTRAL NEW YORK DURING THIS AFTERNOON AND INTERACT WITH VERY MOIST
AIR WITH THUNDERSTORMS ONCE AGAIN DEVELOPING IN THE INCREASINGLY
UNSTABLE AIRMASS. THESE STORMS WILL SLOWLY HEAD NE DURING THE
REMAINDER OF THE AFTERNOON. WITH THE LOSS OF DAYTIME
HEATING...EXPECT A LULL IN ANY THUNDERSTORM DEVELOPMENT OVERNIGHT.
RENEWED CONVECTION IS EXPECTED IN THE SOUTHERN TIER BY ABOUT 18Z
SATURDAY.
WHILE MAINLY VFR CIGS ARE EXPECTED...ANY PASSING THUNDERSTORM COULD
PRODUCE HEAVY RAIN AND LOWER VSBYS TO MVFR OR IFR FOR A BRIEF TIME.
OUTLOOK...
SUNDAY....MAINLY VFR. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
MONDAY AND TUESDAY...MAINLY VFR. CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES WELL BELOW SCA CRITERIA TODAY THROUGH TODAY.
THE EXCEPTION TO THIS GENERAL TREND WILL BE IN THE VICINITY OF
PASSING THUNDERSTORMS WHICH WILL MAY BE ACCOMPANIED BY VERY HEAVY
RAIN AND GUSTY WINDS.
SOUTHWEST WINDS WILL PICK UP A BIT THIS WEEKEND...BUT SCA CONDITIONS
ARE NOT EXPECTED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TJP
NEAR TERM...ZAFF
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...ZAFF
MARINE...TJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
342 AM EDT FRI JUL 5 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL MAINTAIN A
SOUTHERLY FLOW OF WARM AND VERY HUMID AIR OVER OUR REGION THROUGH
THE WEEKEND. THUNDERSTORMS THAT DEVELOP WITHIN THIS HUMID AIRMASS
WILL BE CAPABLE OF PRODUCING VERY HEAVY RAIN AND GUSTY WINDS...BUT
THERE WILL BE FREQUENT RAINFREE PERIODS AS WELL.
&&
.NEAR TERM /THROUGH TONIGHT/...
REGIONAL RADARS SHOW SCATTERED SHOWERS PUSHING EAST ACROSS THE AREA
EARLY THIS MORNING. THE BULK OF THE SHOWERS ARE IN THE VICINITY OF
LAKE ONTARIO WHERE ADDITIONAL LIFT IS BEING GENERATED BY A PASSING
SHORT WAVE.
LOOKING UPSTREAM...A BETTER ORGANIZED AREA OF SHOWERS AND ISOLATED
THUNDERSTORMS IS MOVING NORTH ACROSS OHIO AND WESTERN LAKE ERIE.
THIS PCPN IS ASSOCIATED WITH A BETTER DEFINED SHORT WAVE THAT IS
CENTERED OVER OHIO. EXPECT THIS AREA OF SHOWERS TO CONTINUE TO LIFT
SLOWLY TO THE NORTH EARLY THIS MORNING...THEN SHIFT MORE TO THE EAST
NORTHEAST LATER THIS MORNING AND DURING THE AFTERNOON AS THE SHORT
WAVE ROUNDS THE TOP OF THE UPPER LEVEL RIDGE. THE IMPACT THAT THIS
IMPULSE WILL HAVE ON OUR CWA DEPENDS OF THE PATH THAT IT ULTIMATELY
TAKES...AND THIS IS WHERE SUBTLE DIFFERENCE IN THE DETAILS CAN MAKE
A BIG DIFFERENCE. THE NAM AND ECMWF KEEP THE SHORT WAVE MAINLY
NORTH OF LAKE ONTARIO...WHILE THE GFS AND RAP TRACK IT FARTHER TO
THE SOUTH...PUSHING IT RIGHT ACROSS WESTERN AND CENTRAL NEW YORK
DURING THE AFTERNOON. USING THE 1000-500 MB THICKNESS LINES AS AN
ADDITIONAL GUIDE FAVORS THE MORE SOUTHWARD TRACK OF THE GFS AND RAP.
FOLLOWING THE MORE SOUTHWARD TREND...WILL MAINTAIN HIGH LIKELY TO
CATEGORICAL POPS ACROSS OUR CWA DURING THE AFTERNOON.
THE VERY HIGH ATMOSPHERIC MOISTURE CONTENT THAT IS IN PLACE WILL
ONCE AGAIN BRING THE POTENTIAL FOR HEAVY RAINFALL PRODUCING
THUNDERSTORMS. AS WAS THE CASE THE PAST FEW DAYS...THIS WILL NOT BE
A WIDESPREAD HEAVY RAIN EVENT...BUT WHERE THUNDERSTORMS DO OCCUR
THEY MAY BRING 1 TO 2 INCHES OF RAIN IN A RELATIVELY SHORT
TIME...WHICH COULD LEAD TO LOCALIZED FLOODING.
EXPECT ONGOING SHOWERS/THUNDERSTORMS TO DIMINISH THIS EVENING WITH
THE LOSS OF DAYTIME HEATING...WHILE THE LIFT FROM THE SHORT WAVE
PUSHES EAST OF OUR CWA. A JET STREAK THAT WILL BE PASSING JUST NORTH
OF LAKE ONTARIO MAY BRING A FEW MORE SHOWERS TO AREAS EAST OF LAKE
ONTARIO LATE TONIGHT.
AFTERNOON TEMPERATURES TODAY WILL WARM INTO THE UPPER 70S/LOWER 80S
ACROSS WESTERN NEW YORK...WHILE THE WARMER SPOTS ACROSS THE GENESEE
VALLEY AND FINGER LAKES RISE INTO THE MID AND UPPER 80S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE UNSETTLED PATTERN WILL CONTINUE THROUGH THE SHORT TERM AS A MID
LEVEL CUTOFF LOW DRIFTS SLOWLY FROM THE MID MISSISSIPPI VALLEY TO
THE OHIO VALLEY THROUGH THE PERIOD. A STRONG BERMUDA HIGH WILL ALSO
REMAIN IN PLACE...WITH DEEP SOUTHERLY FLOW BETWEEN THESE TWO
FEATURES KEEPING A FEED OF DEEP TROPICAL MOISTURE FROM THE GULF OF
MEXICO FLOWING NORTHWARD INTO THE REGION. NUMEROUS LOW AMPLITUDE AND
DIFFICULT TO TIME SHORTWAVES WILL PROPAGATE AROUND THE WESTERN
PERIPHERY OF THE BERMUDA HIGH THROUGH THE PERIOD AND SUPPORT
ENHANCED COVERAGE OF SHOWERS AND A FEW THUNDERSTORMS AT TIMES. THIS
WILL BE SUPERIMPOSED ON THE DIURNAL CYCLE...WHICH IN GENERAL WILL
SUPPORT BEST COVERAGE OF SHOWERS DURING THE AFTERNOON AND EARLY
EVENING WITH LESSER COVERAGE DURING THE LATE NIGHT AND EARLY MORNING
HOURS.
LOOKING AT THE DETAILS...ON SATURDAY MODEL GUIDANCE SUGGESTS ONE OR
TWO VERY WEAK MID LEVEL SHORTWAVES MAY CROSS THE LOWER LAKES DURING
THE DAY...BUT IT APPEARS THE DIURNAL CYCLE WILL DOMINATE FORCING FOR
ANY CONVECTION. BOTH NAM/GFS BOUNDARY LAYER MOISTURE FLUX DIVERGENCE
FIELDS SUGGEST THE BEST CONVERGENCE WILL DEVELOP ACROSS THE HIGHER
TERRAIN OF THE SOUTHERN TIER AND FINGER LAKES...AND ALSO ALONG THE
LAKE ONTARIO LAKE BREEZE TO THE SOUTH OF THE LAKE. THESE SUBTLE
BOUNDARIES WILL PROVIDE A FOCUS FOR AFTERNOON SHOWER AND
THUNDERSTORM DEVELOPMENT. THE LOWEST RAIN CHANCES BY AFTERNOON WILL
BE NORTHEAST OF BOTH LAKES ERIE AND ONTARIO AS MORE STABLE LAKE
INFLUENCED AIR SPREADS INLAND.
SATURDAY EVENING MOST OF THIS ACTIVITY WILL SLOWLY DISSIPATE WITH
THE LOSS OF DAYTIME HEATING. LATE SATURDAY NIGHT ONE OR TWO WEAK
SHORTWAVES WILL AGAIN CROSS THE LOWER LAKES REGION ALONG WITH AN
INCREASE IN DEEP LAYER MOISTURE. THIS MAY PRODUCE A FEW WIDELY
SCATTERED SHOWERS LATE.
BY SUNDAY THE MID LEVEL CUTOFF LOW OVER THE MIDWEST WILL BEGIN TO
OPEN UP AND RE-ENGAGE WITH THE WESTERLIES. THIS WILL SPREAD HEIGHT
FALLS AND DPVA INTO THE LOWER LAKES REGION WHICH WILL SUPPORT AN
INCREASE IN LARGE SCALE ASCENT. THIS WILL AGAIN PRODUCE AT LEAST
SCATTERED SHOWERS AND A FEW THUNDERSTORMS...WITH THE GREATEST
COVERAGE EXPECTED FROM THE SOUTHERN TIER INTO THE FINGER LAKES AND
CENTRAL NY WITH SOME HELP FROM THE DIURNAL CYCLE AND ASSOCIATED
DIFFERENTIAL HEATING BOUNDARIES. SUNDAY NIGHT THE MID LEVEL CUTOFF
WILL CONTINUE TO MAKE HEADWAY EAST AND APPROACH THE REGION. THE
INCREASE IN LARGE SCALE ASCENT MAY KEEP A FEW SHOWERS GOING INTO THE
NIGHT DESPITE THE LOSS OF DAYTIME HEATING.
PWAT THROUGH THE PERIOD WILL RUN CLOSE TO 2 INCHES AT TIMES. THIS
WILL CONTINUE TO SUPPORT A RISK FOR TORRENTIAL DOWNPOURS AND
ASSOCIATED ISOLATED FLOOD RISK FROM ANY THUNDERSTORM WHICH
DEVELOPS...ESPECIALLY IF TRAINING OCCURS ALONG ANY OF THE LOW LEVEL
BOUNDARIES.
IT WILL REMAIN MUGGY THROUGH THE PERIOD WITH WARM OVERNIGHT LOWS AND
HIGHS JUST SLIGHTLY ABOVE AVERAGE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
A SLOW IMPROVING TREND IN SENSIBLE WEATHER WILL TAKE PLACE DURING
THE LONG TERM AS THE PATTERN ACROSS NORTH AMERICA EVOLVES. A ZONAL
PATTERN WILL TAKE HOLD ALONG THE US/CANADIAN BORDER WHICH IN TIME
WILL FORCE DEEPER TROPICAL MOISTURE BACK SOUTH AND AWAY FROM THE
REGION. THE BERMUDA HIGH WILL ALSO WEAKEN A LITTLE AND MOVE FARTHER
OFFSHORE...ENDING THE SOUTHERLY PUMP OF DEEP MOISTURE INTO THE
NORTHEAST STATES.
AT THE START OF THE PERIOD MONDAY AND MONDAY NIGHT THE OLD
MIDWEST CUTOFF LOW WILL PASS BY JUST TO THE SOUTH OF THE AREA. THIS
WILL CONTINUE TO SUPPORT A FEW SCATTERED SHOWERS AND THUNDERSTORMS.
BY TUESDAY A WEAK BUBBLE OF HIGH PRESSURE WILL BUILD INTO THE GREAT
LAKES AND PROVIDE A MUCH NEEDED MAINLY DRY DAY.
BY WEDNESDAY BOTH THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL BRING BACK THE CHANCE OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A RETURN TO MAINLY DRY WEATHER.
TEMPERATURES WILL CONTINUE TO RUN A LITTLE ABOVE AVERAGE THROUGH
MOST OF THE PERIOD WITH VERY MUGGY CONDITIONS. THIS WILL IMPROVE BY
THURSDAY WITH A DRIER AND LESS HUMID AIRMASS BUILDING INTO THE
REGION BEHIND A STRONGER COLD FRONT.
LOOKING A LITTLE FARTHER AHEAD...SOME PROMISE IS SEEN FOR A MORE
EXTENDED PERIOD OF DRYING LATER NEXT WEEK THROUGH NEXT WEEKEND AS A
BAROCLINIC ZONE GETS FORCED MAINLY SOUTH OF THE AREA AS A TROUGH
DIGS INTO EASTERN CANADA. THIS WOULD PUT OUR REGION ON THE DRIER AND
LESS HUMID SIDE OF THE BOUNDARY...WITH LOWER RH DAYS GIVING SOILS A
CHANCE TO DRY OUT.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
A MOISTURE LADEN AIRMASS WILL REMAIN IN PLACE ACROSS THE REGION
THROUGH THE TAF PERIOD. A FEW SHOWERS ARE POSSIBLE ACROSS FAR
WESTERN NEW YORK DURING THE EARLY MORNING HOURS...BUT MOST OF THE
AREA WILL STAY DRY DURING THE EARLY MORNING HOURS. WHILE MAINLY VFR
CIGS WILL PREVAIL...NEARLY SATURATED AIR IN THE LOWEST LEVELS WILL
RESULT IN MVFR TO IFR VSBYS AT TIMES.
A MID LEVEL SHORT WAVE ROTATING AROUND THE WESTERN PERIPHERY OF THE
UPPER RIDGE IS GENERATING AN AREA OF SHOWERS AND SCATTERED
THUNDERSTORMS OVER OHIO. THIS PCPN WILL CONTINUE TO LIFT SLOWLY TO
THE NORTHEAST AND IMPACT THE FAR WESTERN TAF SITES LATER THIS
MORNING. AS THE SHORT WAVE PUSHES EAST ACROSS CENTRAL NEW YORK
DURING THE AFTERNOON AND INTERACTS WITH THE VERY MOIST AIR...
SHOWERS AND SCATTERED THUNDERSTORMS MAY BECOME MORE WIDESPREAD
DURING THE AFTERNOON. ONCE AGAIN...MAINLY VFR CIGS WILL BE THE
RULE...BUT ANY PASSING STORM COULD PRODUCE HEAVY RAIN AND LOWER
VSBYS TO IFR FOR A BRIEF TIME.
OUTLOOK...
SATURDAY AND SUNDAY....MAINLY VFR. A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS.
MONDAY...MAINLY VFR. CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES WELL BELOW SCA CRITERIA TODAY THROUGH TODAY.
THE EXCEPTION TO THIS GENERAL TREND WILL BE IN THE VICINITY OF
PASSING THUNDERSTORMS WHICH WILL MAY BE ACCOMPANIED BY VERY HEAVY
RAIN AND GUSTY WINDS.
SOUTHWEST WINDS WILL PICK UP A BIT THIS WEEKEND...BUT SCA CONDITIONS
ARE NOT EXPECTED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TJP
NEAR TERM...TJP
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...TJP
MARINE...TJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
805 PM EDT SAT JUL 6 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL EXTEND WESTWARD INTO THE CAROLINAS
THROUGH THE WEEKEND. A WEAKENING UPPER LEVEL LOW CURRENTLY STALLED
OVER THE CENTRAL MISSISSIPPI RIVER VALLEY WILL TRACK SLOWLY EAST
ACROSS THE MID-ATLANTIC ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 PM SATURDAY...
ISOLATED SHOWERS CONTINUE ACROSS THE AREA THIS AFTERNOON...MOST
LIKELY DRIVEN BY A WEAK SURFACE WAVE OVER CENTRAL NC...AND SHOWERS
ALONG THE SEA BREEZE APPROACHING FROM THE SE WILL CONTINUE TO DRIFT
NORTHWARD THROUGH SUNSET. SO FAR THE HRRR HAS HAD THE BEST HANDLE ON
SHOWER ACTIVITY TODAY...SO WILL CONTINUE TO RELY ON THAT FORECAST
FOR PRECIP THROUGH TONIGHT. WINDS CONTINUE TO BE MAINLY SOUTHERLY OR
SSW AND SHOULD BECOME LIGHT OVERNIGHT. WITH LITTLE CHANGE IN THE
OVERALL PATTERN FROM THE LAST DAY OR SO...EXPECT LOWS TONIGHT
SIMILAR TO PREVIOUS DAYS...IN THE LOWER 70S.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 240 PM SATURDAY...
THE UPPER LEVEL LOW OVER THE MISSISSIPPI RIVER VALLEY WILL SLOWLY
MOVE ENE TOWARD THE NE US THROUGH SUNDAY NIGHT...DAMPENING THE HIGH
OVER CENTRAL NC AS THE TROUGH MOVES INTO THE AREA. WHILE THE SURFACE
HIGH SHOULD REMAIN IN PLACE...EXPECT A REFLECTION OF THE TROUGH TO
SHOW UP...AND WINDS TO BECOME MORE SOUTHWEST. SHOWER DEVELOPMENT
WILL CONTINUE TO BE DIURNALLY DRIVEN...WITH BEST CHANCES FOR RAIN
ACROSS THE WEST WHERE THE STRONGEST SW FLOW AND MOISTURE ADVECTION
SHOULD BE. HIGHS SUNDAY SIMILAR TO TODAY...MID 80S TO AROUND 90...
ALTHOUGH DEPENDING ON SHOWER DEVELOPMENT/COVERAGE...COULD BE A BIT
LOWER IN THE WEST. OVERNIGHT LOWS SIMILAR TO PREVIOUS NIGHTS...IN
THE LOW 70S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 225 PM SATURDAY...
FOR MONDAY/MONDAY NIGHT: THE CORE OF THE SHORTWAVE TROUGH THAT
PASSES OVER THE OH VALLEY SUNDAY IS EXPECTED TO BE LOCATED OVER NRN
WV AT 12Z MONDAY... FOLLOWING THE TIMING OF THE NAM/ECMWF/EC ENS
MEAN. (THE GFS HAS DEAMPLIFIED AND SPED UP IN RECENT RUNS...
ALTHOUGH IT DOES HAVE SUPPORT FROM THE CANADIAN MODEL... AND THUS
THE FORECAST CONFIDENCE IS LOWER THAN USUAL.) THE SHORTWAVE THEN
DAMPENS AS IT TRACKS TO THE ENE ACROSS THE NORTHEAST STATES AND JUST
OFF NEW ENGLAND BY DAYBREAK TUESDAY... LEAVING BEHIND A BAGGY WEAK
POSITIVELY TILTED TROUGH BACK ACROSS THE SRN APPALACHIANS. DEEP
LAYER BULK SHEAR REMAINS FAVORABLE (25-30 KTS) IN THE NORTHERN FOR
ORGANIZED CONVECTION EARLY IN THE DAY... WITH HIGHER VALUES OF
K-INDEX/LOW LEVEL MOISTURE FLUX/PW (1.8-2.0 IN.) STREAKING ACROSS
THE WRN AND NRN CWA DURING THE MORNING... ALONG THE LOW LEVEL TROUGH
AND ATTENDING WEAKENING DPVA ALOFT. WILL PLACE GOOD CHANCE POPS
ACROSS MUCH OF THE PIEDMONT AND SANDHILLS WITH LOWER POPS IN THE SE
WHERE DEEP MID LEVEL DRY AIR WILL HANG ON. THE DEEP LAYER SHEAR
WANES DURING THE AFTERNOON AS THE WAVE LIFTS OUT... BUT WITH BOTH PW
AND MOISTURE FLUX REMAINING ELEVATED WHILE MLCAPE PEAKS AT 1000-1600
J/KG... SUPPORT PERSISTS FOR AT LEAST SCATTERED SHOWERS AND STORMS
THROUGH THE DAY WITH THE BEST COVERAGE EASING EASTWARD ACROSS
CENTRAL NC FOLLOWING THE DRIFT OF THE WEAK TRAILING TROUGH AXIS.
WILL TAPER POPS DOWN TO A LOW CHANCE OF SHOWERS OVERNIGHT AS WE KEEP
THE SOMEWHAT MOIST COLUMN BUT LOSE THE INSTABILITY AND DYNAMICS.
MOSTLY CLOUDY SKIES SHOULD SHAVE A FEW DEGREES OFF FULL-SUN DAYTIME
TEMPS... AND EXPECT HIGHS OF 84 NW TO NEAR 90 SE. LOWS 70-73.
FOR TUESDAY/TUESDAY NIGHT: A WEAK SURFACE TROUGH AND VERY SUBTLE MID
LEVEL TROUGH AXIS HOLD OVER NC... AS THE MEAN LONGWAVE TROUGH STARTS
TO DIG OVER THE UPPER MIDWEST. FAIRLY DEEP MOISTURE PERSISTS OVER
CENTRAL NC... ALTHOUGH MODELS DIFFER QUITE A BIT WITH THE NAM
SHOWING PW VALUES AROUND 1.75 INCHES (WITH DRIER MID LEVEL AIR)
WHILE THE GFS DEPICTS A PW AXIS AROUND 2.1 INCHES. THIS LEADS TO A
WETTER TUESDAY ON THE GFS THAN THE NAM... ALTHOUGH BOTH MODELS ALONG
WITH THE ECMWF AND SREF MEAN SUGGEST GREATER PRECIP COVERAGE OVER
THE WRN HALF OF NC COMPARED TO THE EAST. PROJECTED MLCAPE RISING
WITH HEATING TO 1500-2000 J/KG AND AVAILABLE MOISTURE SHOULD SUPPORT
AT LEAST SCATTERED CONVECTION WITH HEATING... ALTHOUGH THE LACK OF
GOOD KINEMATICS AND LARGE SCALE FORCING FOR ASCENT WILL LIMIT
COVERAGE AND INTENSITY. WILL ONCE AGAIN HAVE POPS TAPERING DOWN TO
SLIGHT CHANCE AFTER SUNSET AND THROUGH THE OVERNIGHT HOURS. HIGHS
87-90 WITH THICKNESSES CLOSE TO SEASONAL NORMALS. LOWS 70-73.
FOR WEDNESDAY THROUGH SATURDAY: RIDGING HOLDS FIRM OVER NM HEADING
INTO LATE WEEK WHILE LONGWAVE TROUGHING DEEPENS OVER THE GREAT LAKES
THEN OVER THE EASTERN US. THE GFS/ECMWF DEVELOP SCATTERED CONVECTION
MAINLY OVER ERN TN AND SRN APPALACHIANS INTO THE WRN CWA WEDNESDAY
AFTERNOON... WITH THE MORE ORGANIZED ACTIVITY WELL TO THE NW OVER
THE OH VALLEY AHEAD OF THE INCOMING COLD FRONT. WILL KEEP POPS AS
CHANCE OVER CENTRAL NC... HIGHER WEST THAN EAST. THEN AS THE COLD
FRONT APPROACHES WITH THE DEEPENING TROUGH... EXPECT AN EXPANSION OF
THE BETTER CHANCE OF SHOWERS/STORMS TO THE ESE INTO NC... PEAKING
THURSDAY NIGHT INTO FRIDAY OVER CENTRAL NC ACCORDING TO THE ECMWF
AND EC ENS MEAN... AND SHIFTING INTO THE COASTAL PLAIN AND COAST ON
SATURDAY AS THE FRONT PUSHES THROUGH THE AREA. MODELS HAVE COME INTO
SUFFICIENTLY CLOSE AGREEMENT SUCH THAT CONFIDENCE IS JUST HIGH
ENOUGH TO GO WITH POPS RANGING FROM 40% SE TO 60% NW ON THURSDAY...
LOWERING A BIT TO CHANCE THURSDAY NIGHT... THEN 50-60% ON FRIDAY...
HIGHER EAST THAN WEST AS THE MID LEVEL TROUGH AXIS PUSHES OVER THE
MOUNTAINS. THE GFS/ECMWF TAKE THE SURFACE COLD FRONT INTO ERN NC BY
SATURDAY BUT WITH GROWING UNCERTAINTY THAT FAR OUT IN THE
FORECAST... WILL RETAIN A CHANCE OF SHOWERS/STORMS MAINLY IN THE
EAST AS THE MID LEVEL TROUGH IS LIKELY TO STALL OUT OVER THE REGION.
WILL STAY WITH PERSISTENCE WITH HIGHS IN THE UPPER 80S TO AROUND
90... SLIPPING ABOUT A CATEGORY BY LATE WEEK AS THICKNESSES TREND
DOWN BELOW NORMAL. NIGHTLY LOWS IN THE UPPER 60S TO LOWER 70S. -GIH
&&
.AVIATION /00Z SUNDAY THROUGH WEDNESDAY/...
AS OF 800 PM SATURDAY...
THERE ARE STILL A FEW SHOWERS MOVING NORTH THROUGH THE WESTERN
PIEDMONT THIS EVENING...BUT THE BULK OF ACTIVITY HAS MOVED NORTH OF
KGSO AND KINT. HIGH PRESSURE CONTINUES TO EXTEND ACROSS THE STATE
FROM THE WESTERN ATLANTIC...AND PERSISTENCE SHOULD PREVAIL IN THE
FORECAST. THUS... MVFR/IFR STRATUS WILL BE POSSIBLE AT KGSO AND
KINT...WITH THE PROBABILITY OF IFR/LIFR FOG HIGHER TO THE
EAST...PARTICULARLY AT KRWI AND KFAY. AFTER 12Z...EXPECT A GRADUAL
LIFTING IF CEILINGS THROUGH THE MORNING HOURS..WITH VFR CONDITIONS
AND A FEW SCATTERED SHOWER/STORMS (WEST) DURING THE AFTERNOON.
OUTLOOK...
STRATUS AND FOG WILL BE POSSIBLE EACH MORNING...MAINLY CENTERED
AROUND THE 09-12Z PERIOD...WITH SCATTERED SHOWERS/STORMS DURING THE
AFTERNOON. THE GREATEST COVERAGE OF SHOWERS AND STORMS WILL LIKELY
BE MONDAY AFTERNOON/EVENING.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...KC
SHORT TERM...KC
LONG TERM...HARTFIELD
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
318 PM CDT FRI JUL 5 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 319 PM CDT FRI JUL 5 2013
FRONTAL BOUNDARY HAS SLOWLY SHIFTED INTO EASTERN ZONES
TODAY...RUNNING ROUGHLY ALONG A WARROAD TO WAHPETON LINE. SPC
MESOANALYSIS SHOWING CAPES DIRECTLY BEHIND FRONT...WHERE DEW
POINTS HAVE BEEN SLIGHTLY HIGHER...AROUND 1000 J/KG. 0 TO 6 KM
BULK SHEAR IS NIL SO WILL BE DIFFICULT TO GET ANYTHING
SIGNIFICANT GOING BUT WILL MAINTAIN LOW POPS IN THE FAR EAST AHEAD
OF FRONT. AN AREA OF SHOWERS/TSTMS IS MOVING EASTWARD ACROSS NORTH
CENTRAL SOUTH DAKOTA WHILE CONVECTION OVER NORTHEASTERN MT HAS NOW
CROSSED INTO FAR NWRN ND AND SOUTHEASTERN SASK. OVERALL NAM HAS
BEST HANDLE ON SD ACTIVITY WHILE HRRR HAS A DECENT HANDLE ON BOTH
CLUSTERS. WILL USE HRRR AS GUIDANCE IN THE NEAR TERM AND A MODEL
BLEND FOR BEYOND 06Z. GEM AND SOMEWHAT THE ECMWF CONTINUE TO
TARGET NORTHERN VALLEY FOR CONVECTION TOMORROW WHILE AMERICAN
MODELS FURTHER SOUTH...THEREFORE WILL MAINTAIN CONTINUITY/MODEL
BLEND WITH MINOR ADJUSTMENTS TO POPS TOMORROW BUT MOVING THINGS
OUT QUICKER ON SAT NIGHT.
TONIGHT...CLUSTER OF STORMS OVER SD PROGGED TO BE INTO SWRN ZONES
AROUND 00Z. DID INCREASE TO CHANCE POPS RANSOM/SARGENT/RICHLAND
COUNTIES EARLY EVENING AND NW ZONES AFT 06Z. NOT TOO CONFIDENT ON
EASTWARD ACTIVITY OF THIS BEFORE ACTIVITY BEGINS TO PETER OUT.
SATURDAY...AS PREVIOUSLY STATED..MODELS CONTINUE TO DIFFER ON
TRACK OF SFC LOW TOMORROW WITH THE GEM FURTHEST NORTH. MODELS DO
SHOW BEST INSTABILITY ACROSS THE SOUTHERN HALF OF THE CWA...WITH
CAPES IN THE 1K TO 2K J/KG BALL PARK. STILL NOT CONFIDENT ENOUGH
ON EXACT PLACEMENT TO INCREASE TO LIKELIES BUT THE CENTRAL AND
NORTHERN VALLEY ARE LOOKING LIKE THE BEST PROBABILITY AS INVERTED
TROUGH EXTENDS UP INTO FGF CWA. 40 KTS OF SHEAR WITH DECENT
INSTABILITY ACROSS SOUTH...SUPPORTING SPC SLIGHT RISK AREA.
SAT NIGHT...BEGAN DECREASING POPS BY 06Z AS ALL MODELS DO PULL
SYSTEM OUT OF ND IN THE 06Z TO 12Z TIMEFRAME.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI JUL 5 2013
SUNDAY WILL BE SEE SOME SFC RIDING EXTEND INTO AREA FROM LOW OVER
SASK/MB. NW FLOW WILL BRING SOME MORE SEASONAL TEMPS...GENERALLY
IN THE MID 80S.
MAIN 500 MB RIDGE FLATTENS AND SPREADS OUT OVER THE SOUTHERN ROCKIES
INTO THE SOUTHERN PLAINS PUTTING OUR AREA IN A MORE WESTERLY FLOW
ALOFT NEXT WEEK. 12Z GFS/12Z EURO IN PRETTY GOOD AGREEMENT IN
SHOWING THE NEXT SHORT WAVE TO IMPACT THE AREA MOVING IN LATER
MONDAY NIGHT INTO TUESDAY WITH A GOOD CHANCE FOR THUNDERSTORMS.
HIGH PRESSURE FOLLOWS LATE WEDNESDAY INTO THURSDAY THEN NEXT SHORT
WAVE STARTS TO MOVE INTO THE AREA LATE THURSDAY NIGHT OR FRIDAY.
TEMPS WILL BE NEAR OR A BIT BELOW AVERAGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 319 PM CDT FRI JUL 5 2013
DIURNAL CUMULUS OVER THE AREA THIS AFTN...THICKEST FROM FARGO
NORTHWEST TOWARD BAUDETTE. THREW IN TEMPO BKN CIGS AT BJI AT 3K FT
FOR THIS AS THICKER BAND MOVING IN FROM THE WEST. PRETTY LIGHT
WIND SPEEDS WITH A MORE NORTHWEST OR NORTH WIND IN ERN ND AND
EXTREME NW MN TO A MORE SOUTHWEST WIND IN WCNTRL MN INTO BEMIDJI
AREA. LIGHT WINDS THIS EVE....THEN EXPECT INCREASING HIGH AND MID
CLOUDS OVERNIGHT INTO SATURDAY MORNING FROM WEST TO EAST WITH
WINDS TURNING EAST-SOUTHEAST NR 10 KTS SATURDAY MORNING. DID THROW
IN CHC OF SHOWER IN DVL 15Z SATURDAY IN CASE OVERNIGHT ACTIVITY IN
WRN ND MAKES IT THAT FAR EAST. DVL HAS BEST CHC...MUCH MORE
UNCERTAIN AT OTHER SITES THRU 18Z TO INCLUDE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...SPEICHER
LONG TERM...RIDDLE/SPEICHER
AVIATION...RIDDLE
PREVIOUS FORECAST DISCUSSION...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE
FORECAST AREA THIS MORNING. THE FOCUS OF THE SHOWER ACTIVITY
APPEARS TO BE ON AN 850MB JET MOVING NORTH. THE JET WILL MOVE
NORTHEAST OF THE FORECAST AREA THIS AFTERNOON. THIS SHOULD ALLOW
THE SHOWER AND THUNDERSTORM AREAL COVERAGE TO DECREASE. STORMS
WILL STILL BE PRESENT AS THE TYPICAL DIURNAL HEATING PATTERN WILL
OCCUR HOWEVER THE AREAL EXTENT WILL BE MUCH LESS AND I WILL TREND
THE FORECAST ACCORDINGLY. THE MAIN PUSH OF THE HEAVIER RAIN THIS
MORNING IS RIGHT ALONG I-71. AT THIS POINT THE AREA OF HEAVY RAIN
IS MOVING FAIRLY QUICKLY AND RAINFALL TOTALS OVER SOUTHERN OHIO
HAVE NOT BEEN OVERLY IMPRESSIVE. I STILL BELIEVE SOME ISOLATED
POCKETS OF FLOODING ARE POSSIBLE PARTICULARLY THIS MORNING. I WILL
LEAVE THE CURRENT FLOOD WATCH IN TACK AT THIS TIME AND ALLOW THE
EVENT TO PLAY OUT. ONCE AGAIN GUIDANCE TEMPS LOOK REASONABLE. A
FEW BREAKS IN THE CLOUD COVER CAN MAKE A SIGNIFICANT DIFFERENCE.
WE MAY SEE A FEW BREAKS THIS AFTERNOON SO I WILL HEDGE TO THE
HIGHER SIDE OF GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A SOUTHERLY FLOW WILL CONTINUE THROUGH THE SHORT TERM PERIOD. ONCE
AGAIN THE MODELS SHOW SEVERAL SHORT WAVES MOVING NORTH THROUGH
THE EAST SIDE OF THE TROUGH. TIMING OF THESE SHORT WAVES WILL BE
DIFFICULT. WHILE I EXPECT SCATTERED SHOWERS THROUGH THE SHORT TERM
PERIOD...THESE WAVES WILL PROVIDE A FOCUS FOR MORE ORGANIZED
WIDESPREAD SHOWER ACTIVITY. BOTH THE NAM AND GFS ARE FAIRLY
CONSISTENT WITH THE TIMING OF ONE OF THE WAVES AROUND 12Z SATURDAY
MOVING THROUGH MOST OF THE FORECAST AREA BY 00Z SUNDAY. ANOTHER
MORE SIGNIFICANT WAVE WILL OCCUR 18Z SUN TO 06Z MON. THIS WILL
OCCUR AS THE UPPER LEVEL SHORT WAVE FINALLY MOVES EAST. DYNAMICS
WITH THE MOVEMENT OF THE LOW SHOULD BE SIGNIFICANT ENOUGH TO PRODUCE
WIDESPREAD SHOWERS AND THUNDERSTORMS. HEAVY RAIN WILL CONTINUE TO
BE A CONCERN THROUGH THE PERIOD. IF SHOWERS OR THUNDERSTORMS
PERSIST IN ANY ONE AREA...FLOODING WILL OCCUR. THIS IS PARTICULARLY
TRUE FOR THE PERIOD SUNDAY INTO MONDAY MORNING.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT AND THAT WILL START
DRYING THINGS OUT FOR A FEW DAYS...LOWER HUMIDITY LEVELS ALSO. IN
THE MEANTIME THE THREAT OF SHOWERS AND THUNDERSTORMS CONTINUE FOR
TUESDAY INTO WEDNESDAY NIGHT. AT THE MOMENT KEPT LIKELY POPS FOR
WEDNESDAY. THIS MAY BE REASONABLE AS THE FRONT WILL BE
APPROACHING...IT WILL DEFINITELY BE THE DAY WITH THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS. MADE ONLY MINOR CHANGES TO THE
TEMPERATURE FORECAST.
&&
.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
A BATCH OF SHOWERS AND SCATTERED THUNDERSTORMS HAVE STARTED TO
MOVE INTO THE FORECAST AREA FROM THE SOUTH AS EXPECTED. THE
QUESTION IS HOW LONG WILL IT LAST...IT MAY ONLY BE 4 TO 5 HOURS
AND THEN A BREAK AS PER THE HRRR MODEL. SOME IFR CEILINGS ARE
EXPECTED AS PER WHAT IS GOING ON UPSTREAM. AS WE GET INTO THE BREAK
LATER TODAY AND CONDITIONS SHOULD TRY TO BECOME VFR. SOME QUESTION
HOW MUCH SHOWER AND THUNDERSTORM ACTIVITY WILL OCCUR THIS
AFTERNOON AND TONIGHT. AT THIS TIME WAS OPTIMISTIC AND DIDN`T
MENTION MUCH WEATHER IN THE TAFS AFTER 17Z.
ON THE EDGE WHETHER A LAKE BREEZE WILL GET TO CLE...AT THIS TIME
IT LOOKS LIKE THE GRADIENT WILL BE TOO STRONG...CONFIDENCE IS LOW.
THE LAKE BREEZE SHOULD MAKE IT TO ERI.
.OUTLOOK...NON-VFR IN SHOWERS/THUNDERSTORMS AS WELL AS EARLY
MORNING FOG THROUGH TUESDAY.
&&
.MARINE...
THE THREAT FOR A SMALL CRAFT ADVISORY IS VERY LOW INTO EARLY NEXT
WEEK AS A MAINLY SOUTHWEST FLOW WILL CONTINUE ON THE LAKE. THE
GRADIENT WILL BE WEAK ENOUGH THIS AFTERNOON FOR AN ONSHORE FLOW
MAINLY EAST OF CLEVELAND. THERE IS A THREAT FOR AN ONSHORE FLOW
SATURDAY AFTERNOON FOR THE ENTIRE NEARSHORE WATERS AS THE GRADIENT
WILL BE WEAK ENOUGH. THE ONSHORE FLOW MAY HAPPEN AGAIN SUNDAY
AFTERNOON. HOWEVER...THE WINDS ALOFT MAY BE A LITTLE STRONGER...THIS
WILL HAVE TO BE MONITORED.
A COLD FRONT WILL MOVE ACROSS THE LAKE WEDNESDAY NIGHT AND THAT WILL
SHIFT THE WINDS TO THE NORTHWEST. THE WINDS COULD BE STRONG ENOUGH
TO PROMPT A SMALL CRAFT ADVISORY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR OHZ003-
006>011-017>020-027>030-036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
323 AM EDT FRI JUL 5 2013
.SYNOPSIS...
A NEARLY STATIONARY UPPER LEVEL LOW OVER THE MISSISSIPPI VALLEY WILL
CONTINUE TO PUSH WARM MOIST AREA OVER THE OHIO VALLEY THROUGH THE
WEEKEND. THIS SYSTEM WILL BEGIN TO MOVE EAST OF THE AREA ON
MONDAY. &&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS THE FORECAST
AREA THIS MORNING. THE FOCUS OF THE SHOWER ACTIVITY APPEARS TO BE
ON AN 850MB JET MOVING NORTH. THE JET WILL MOVE NORTHEAST OF
THE FORECAST AREA THIS AFTERNOON. THIS SHOULD ALLOW THE SHOWER AND
THUNDERSTORM AREAL COVERAGE TO DECREASE. STORMS WILL STILL BE
PRESENT AS THE TYPICAL DIURNAL HEATING PATTERN WILL OCCUR HOWEVER
THE AREAL EXTENT WILL BE MUCH LESS AND I WILL TREND THE FORECAST
ACCORDINGLY. THE MAIN PUSH OF THE HEAVIER RAIN THIS MORNING IS
RIGHT ALONG I-71. AT THIS POINT THE AREA OF HEAVY RAIN IS MOVING
FAIRLY QUICKLY AND RAINFALL TOTALS OVER SOUTHERN OHIO HAVE NOT BEEN
OVERLY IMPRESSIVE. I STILL BELIEVE SOME ISOLATED POCKETS OF
FLOODING ARE POSSIBLE PARTICULARLY THIS MORNING. I WILL LEAVE THE
CURRENT FLOOD WATCH IN TACK AT THIS TIME AND ALLOW THE EVENT TO PLAY
OUT. ONCE AGAIN GUIDANCE TEMPS LOOK REASONABLE. A FEW BREAKS IN THE
CLOUD COVER CAN MAKE A SIGNIFICANT DIFFERENCE. WE MAY SEE A FEW
BREAKS THIS AFTERNOON SO I WILL HEDGE TO THE HIGHER SIDE OF GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
A SOUTHERLY FLOW WILL CONTINUE THROUGH THE SHORT TERM PERIOD. ONCE
AGAIN THE MODELS SHOW SEVERAL SHORT WAVES MOVING NORTH THROUGH
THE EAST SIDE OF THE TROUGH. TIMING OF THESE SHORT WAVES WILL BE
DIFFICULT. WHILE I EXPECT SCATTERED SHOWERS THROUGH THE SHORT TERM
PERIOD...THESE WAVES WILL PROVIDE A FOCUS FOR MORE ORGANIZED
WIDESPREAD SHOWER ACTIVITY. BOTH THE NAM AND GFS ARE FAIRLY
CONSISTENT WITH THE TIMING OF ONE OF THE WAVES AROUND 12Z SATURDAY
MOVING THROUGH MOST OF THE FORECAST AREA BY 00Z SUNDAY. ANOTHER
MORE SIGNIFICANT WAVE WILL OCCUR 18Z SUN TO 06Z MON. THIS WILL
OCCUR AS THE UPPER LEVEL SHORT WAVE FINALLY MOVES EAST. DYNAMICS
WITH THE MOVEMENT OF THE LOW SHOULD BE SIGNIFICANT ENOUGH TO PRODUCE
WIDESPREAD SHOWERS AND THUNDERSTORMS. HEAVY RAIN WILL CONTINUE TO
BE A CONCERN THROUGH THE PERIOD. IF SHOWERS OR THUNDERSTORMS
PERSIST IN ANY ONE AREA...FLOODING WILL OCCUR. THIS IS PARTICULARLY
TRUE FOR THE PERIOD SUNDAY INTO MONDAY MORNING.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT AND THAT WILL START
DRYING THINGS OUT FOR A FEW DAYS...LOWER HUMIDITY LEVELS ALSO. IN
THE MEANTIME THE THREAT OF SHOWERS AND THUNDERSTORMS CONTINUE FOR
TUESDAY INTO WEDNESDAY NIGHT. AT THE MOMENT KEPT LIKELY POPS FOR
WEDNESDAY. THIS MAY BE REASONABLE AS THE FRONT WILL BE
APPROACHING...IT WILL DEFINITELY BE THE DAY WITH THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS. MADE ONLY MINOR CHANGES TO THE
TEMPERATURE FORECAST.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
A BATCH OF SHOWERS AND SCATTERED THUNDERSTORMS HAVE STARTED TO
MOVE INTO THE FORECAST AREA FROM THE SOUTH AS EXPECTED. THE
QUESTION IS HOW LONG WILL IT LAST...IT MAY ONLY BE 4 TO 5 HOURS
AND THEN A BREAK AS PER THE HRRR MODEL. SOME IFR CEILINGS ARE
EXPECTED AS PER WHAT IS GOING ON UPSTREAM. AS WE GET INTO THE BREAK
LATER TODAY AND CONDITIONS SHOULD TRY TO BECOME VFR. SOME QUESTION
HOW MUCH SHOWER AND THUNDERSTORM ACTIVITY WILL OCCUR THIS
AFTERNOON AND TONIGHT. AT THIS TIME WAS OPTIMISTIC AND DIDN`T
MENTION MUCH WEATHER IN THE TAFS AFTER 17Z.
ON THE EDGE WHETHER A LAKE BREEZE WILL GET TO CLE...AT THIS TIME
IT LOOKS LIKE THE GRADIENT WILL BE TOO STRONG...CONFIDENCE IS LOW.
THE LAKE BREEZE SHOULD MAKE IT TO ERI.
.OUTLOOK...NON-VFR IN SHOWERS/THUNDERSTORMS AS WELL AS EARLY
MORNING FOG THROUGH TUESDAY.
&&
.MARINE...
THE THREAT FOR A SMALL CRAFT ADVISORY IS VERY LOW INTO EARLY NEXT
WEEK AS A MAINLY SOUTHWEST FLOW WILL CONTINUE ON THE LAKE. THE
GRADIENT WILL BE WEAK ENOUGH THIS AFTERNOON FOR AN ONSHORE FLOW
MAINLY EAST OF CLEVELAND. THERE IS A THREAT FOR AN ONSHORE FLOW
SATURDAY AFTERNOON FOR THE ENTIRE NEARSHORE WATERS AS THE GRADIENT
WILL BE WEAK ENOUGH. THE ONSHORE FLOW MAY HAPPEN AGAIN SUNDAY
AFTERNOON. HOWEVER...THE WINDS ALOFT MAY BE A LITTLE STRONGER...THIS
WILL HAVE TO BE MONITORED.
A COLD FRONT WILL MOVE ACROSS THE LAKE WEDNESDAY NIGHT AND THAT WILL
SHIFT THE WINDS TO THE NORTHWEST. THE WINDS COULD BE STRONG ENOUGH
TO PROMPT A SMALL CRAFT ADVISORY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR OHZ003-006>011-
017>020-027>030-036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
152 AM EDT FRI JUL 5 2013
.SYNOPSIS...
AN UPPER LEVEL TROUGH JUST WEST OF THE MISSISSIPPI RIVER VALLEY
WILL CONTINUE TO PUMP MOISTURE INTO OHIO FROM THE GULF OF MEXICO.
THIS UPPER LEVEL TROUGH MAY MOVE ACROSS THE REGION SUNDAY NIGHT
INTO MONDAY ALLOWING A WEAK COLD FRONT TO CROSS THE REGION BY
TUESDAY MORNING.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATE...LIGHT RAIN SHOWERS/SPRINKLES MOVING INTO WRN AND SWRN
COUNTIES FROM HANCOCK TO MARION COUNTIES WHILE HEAVIER SHOWERS ARE
ABOUT TO MOVE INTO THE SRN AND SERN COUNTIES FROM KNOX AND HOLMES
TO STARK. OTHERWISE MOSTLY RAIN FREE THROUGH THE EARLY EVENING
INTO MID EVENING HOURS. SHOWERS AND A FEW THUNDERSTORMS WILL FILL
IN LATE EVENING AND OVERNIGHT. NO CHANGES IN ZONES ALTHOUGH DID
ADJUST GRAPHICS BASED ON TIMING FROM RADAR.
PREVIOUS...GULF OF MEXICO MOISTURE CONTINUES TO BE PUMPED INTO
THE REGION WITH AN UPPER LEVEL TROUGH PARKED JUST WEST OF THE
MISSISSIPPI RIVER VALLEY. RIPPLES OF LOW PRESSURE MOVING THROUGH
THIS FLOW WILL BRING ROUNDS OF RAINFALL TO THE REGION.
AFTERNOON HEATING HAS BEEN ENOUGH TO GENERATE A FEW THUNDERSTORMS
ACROSS THE REGION. ONE CLUSTER ACROSS THE WEST WHERE THE BETTER
JET DYNAMICS ARE LOCATED AND ALSO ALONG THE LAKE SHORE OF NE OHIO
INTO NW PA. AS THE INFLUENCE OF THE JET ENERGY MOVING THROUGH THE
TROUGH INCREASES ACROSS WESTERN OHIO WE EXPECT TO SEE THE COVERAGE
OF THE RAINFALL INCREASE. AS IT DOES IT WILL CAUSE THE SHOWERS AND
EMBEDDED THUNDERSTORMS TO TRAIN ACROSS THE WESTERN HALF OF THE
REGION. THIS SHOULD CAUSE RAINFALL AMOUNTS TO EXCEED ONE INCH WITH
LOCALLY HIGHER AMOUNTS AROUND 3 INCHES POSSIBLE. THESE RAINFALL
AMOUNTS WITH THE ALREADY SATURATED SOIL SHOULD LEAD TO AREAS OF
FLOODING AND RISE ALONG AREA CREEKS AND RIVERS. SO WITH ALL THIS
SAID WE WILL GO WITH A FLASH FLOOD WATCH FOR LOCATIONS WEST OF A
LINE FROM CLEVELAND TO MOUNT VERNON.
AFTER THE EVENING CONVECTION ACROSS THE EAST THERE SHOULD BE A
LULL IN THE ACTIVITY UNTIL SUNRISE APPROACHES.
LOWS TONIGHT WILL NOT DROP ALL THAT MUCH WITH THE HIGH MOISTURE
LEVELS. LOCATIONS THAT EXPERIENCE THE MOST RAINFALL MAY DIP INTO
THE MIDDLE 60S BRIEFLY. THE REMAINDER OF THE REGION WILL BE IN THE
UPPER 60S TO LOWER 70S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
THE SHOWERS AND FEW THUNDERSTORMS WILL CONTINUE INTO FRIDAY. THEY
SHOULD BEGIN TO LIFT TO THE NORTHEAST INTO THE AFTERNOON WITH AT
LEAST A LULL IN THE ACTIVITY. HOWEVER ANY HEATING SHOULD ALLOW
FOR THE DEVELOPMENT OF SCATTERED CONVECTION AGAIN FOR THE LATE
AFTERNOON AND EVENING. THESE SHOULD DECREASE IN COVERAGE BY
EARLY SATURDAY MORNING. THE WARM MOIST AIRMASS WILL CONTINUE INTO
SATURDAY AND SUNDAY WITH A DIURNAL FLUCTUATION IN THE CONVECTION.
ANY ADDITIONAL RIPPLE OF LOW PRESSURE MOVING THROUGH THE FLOW WILL
ENHANCE THE SHOWERS AND THUNDERSTORMS.
HIGHS WILL ALL HINGE ON THE AMOUNT OF CLOUD COVER. THE MORE
BREAKS THE HIGHER INTO THE 80S WE WILL BE ABLE TO GET.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
BOTH ECMWF AND GFS MOVE LOW PRESSURE ACROSS THE CENTRAL LAKES
DRAGGING A COLD FRONT ACROSS THE AREA. ECMWF CONTINUES TO BE THE
FASTER OF THE TWO MODELS WITH THE LOW. AFTER THAT THE FRONT STALLS
SOUTH OF THE AREA AND LINGERS IN THE AREA THROUGH WEDNESDAY.
CONFIDENCE IS LOW AS TO PRECISELY WHERE THE FRONT WILL STALL SO JUST
LEFT CHANCE POPS GOING THROUGH WEDNESDAY. BOTH MODELS HINT THAT
FRONT WILL FINALLY PUSH SOUTH OF THE AREA ON THURSDAY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
A BATCH OF SHOWERS AND SCATTERED THUNDERSTORMS HAVE STARTED TO
MOVE INTO THE FORECAST AREA FROM THE SOUTH AS EXPECTED. THE
QUESTION IS HOW LONG WILL IT LAST...IT MAY ONLY BE 4 TO 5 HOURS
AND THEN A BREAK AS PER THE HRRR MODEL. SOME IFR CEILINGS ARE
EXPECTED AS PER WHAT IS GOING ON UPSTREAM. AS WE GET INTO THE BREAK
LATER TODAY AND CONDITIONS SHOULD TRY TO BECOME VFR. SOME QUESTION
HOW MUCH SHOWER AND THUNDERSTORM ACTIVITY WILL OCCUR THIS
AFTERNOON AND TONIGHT. AT THIS TIME WAS OPTIMISTIC AND DIDN`T
MENTION MUCH WEATHER IN THE TAFS AFTER 17Z.
ON THE EDGE WHETHER A LAKE BREEZE WILL GET TO CLE...AT THIS TIME
IT LOOKS LIKE THE GRADIENT WILL BE TOO STRONG...CONFIDENCE IS LOW.
THE LAKE BREEZE SHOULD MAKE IT TO ERI.
.OUTLOOK...NON-VFR IN SHOWERS/THUNDERSTORMS AS WELL AS EARLY
MORNING FOG THROUGH TUESDAY.
&&
.MARINE...
WINDS WILL REMAIN OUT OF THE SOUTH TO SOUTHWEST INTO THE EARLY PART
OF NEXT WEEK. HOWEVER...SHOWERS WITH THE THREAT OF SOME
THUNDERSTORMS WILL CONTINUE THIS EVENING. THERE IS SOME QUESTION HOW
STRONG THE STORMS WILL BE AND WHETHER THEY WILL PROMPT THE NEED FOR
SPECIAL MARINE WARNINGS. EVEN IF SPECIAL MARINE WARNINGS ARE NOT
ISSUED THE THUNDERSTORMS CAN STILL CAUSE GUSTY WINDS. MARINERS WILL
HAVE TO BE ALERT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR OHZ003-006>011-
017>020-027>030-036-037-047.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...DJB
AVIATION...KIELTYKA
MARINE...DJB
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1219 PM EDT FRI JUL 5 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EASTERN SEABOARD WILL CONTINUE TO
FUNNEL VERY WARM AND HUMID AIR NORTH INTO THE COMMONWEALTH THROUGH
THE UPCOMING WEEKEND. SCATTERED AFTERNOON AND EARLY EVENING
THUNDERSTORMS WILL DEVELOP TODAY THROUGH SUNDAY. UPPER FLOW
FLATTENS THIS WEEK...BUT DAILY CHANCES FOR SHOWERS AND
THUNDERSTORMS WILL CONTINUE.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
THE BULK OF TODAY LOOKS VERY SIMILAR TO THE LAST COUPLE OF
DAYS...WHICH IS - VERY WARM TO TO HOT...WITH MODERATE TO HIGH
HUMIDITY /SFC DEWPOINTS BETWEEN 65-70F/.
SHOWER ACTIVITY REMAINING MINIMAL LATE THIS MORNING ACROSS CENTRAL
PA...AS SHOWERS OVER W PA WEAKEN AS THEY DRIFT INTO NW MTNS. BUT
HIGH RES MODELS SUCH AS THE 4KM NAM...AND THE HRRR CONTINUE TO
TARGET THE CENTRAL AND NW MTNS FOR THE DEVELOPMENT OF SCT
TSRA...AND POSSIBLY EVEN A FEW SLOW-MOVING/TRAINING BKN LINE
BETWEEN ABOUT 21Z AND 04Z. SURFACE HEATING WILL HELP ISO STORMS
POP BEFORE THAT THOUGH.
GIVEN THE HIGH PWAT AIR OF NEARLY 2 INCHES ACROSS CENTRAL AND WRN
PENN...ANY OF THESE STORMS COULD DUMP VERY HEAVY RAIN OF 1-2
INCHES IN A SHORT AMOUNT OF TIME.
LARGE SCALE...DEEP SUBSIDENCE AND WARMER MID LEVEL TEMPS ON THE
NW EDGE OF THE BERMUDA HIGH WILL LIKELY KEEP THE REGION NEAR...AND
TO THE SE OF INTERSTATE 81 RAIN-FREE DURING THIS PERIOD.
EXPECT HIGH TEMPS VERY SIMILAR TO THURSDAY...AROUND 80F ACROSS
THE HIGHER TERRAIN OF THE NORTH AND WEST...TO AROUND 90F IN THE
SUSQUEHANNA VALLEY.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM SATURDAY/...
THE DEEP PLUME OF MOISTURE /WITH ITS ORIGIN FROM THE
PACIFIC...GOMEX...CARIBBEAN AND ATLANTIC/ AND WESTERN PORTION OF
THE RING OF FIRE WILL MAKE VERY LITTLE HEADWAY EAST FROM THE OHIO
VALLEY INTO SATURDAY...SO EXPECTED BROAD-SCALE CONDITIONS /AND
FINER SCALE CONVECTIVE COVERAGE DURING THE AFTERNOON AND EVENING/
TO BE QUITE SIMILAR TO TODAY /FRIDAY/.
MOST LOCATIONS WILL ONCE AGAIN SEE LITTLE IN THE WAY OF RAIN WITH
PERHAPS 0.10-0.25 BASIN AVERAGE RAINFALL. LOCALIZED...VERY HEAVY
RAIN OF 1-2 INCHES IN UNDER ONE HOUR IS POSSIBLE WITH TRAINING
CELLS...OR STORMS BECOMING ANCHORED TO SOME OF THE FAVORABLE
UPSLOPE FLOW IN THE THE HIGH TERRAIN OF THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MED RANGE GUIDANCE REMAINS IN RELATIVELY GOOD AGREEMENT WITH
RESPECT TO LG SCALE PATTERN INTO EARLY NEXT WEEK...ALL SHOWING CUT
OFF LOW OVR THE MISS VALLY OPENING UP AND LIFTING ACROSS PA ON
SUNDAY OR EARLY MONDAY. AS THIS SYSTEM EDGES CLOSER TO PA...ASSOC
DEEP SOUTHERLY FLOW OF HIGH PWATS /NEARLY 2 INCHES AND PLUS 2-3
SIGMA/ AND INCREASING SWRLY LOW-MID LEVEL SHEAR SHIFTS FROM THE OHIO
VALLEY TO PA ON SATURDAY. THUS...INCREASED CHC OF DIURNALLY-ENHANCED
CONVECTION SAT PM. THE CHC OF CONVECTION REMAINS RELATIVELY HIGH
SUNDAY/MONDAY WITH PASSAGE OF UPPER TROF. EVEN INTO EARLY NEXT WEEK
AS FLOW FLATTENS OUT...PA WILL REMAIN ON NORTHERN PERIPHERY OF
SUBTROPICAL RIDGE CENTERED OVR THE SOUTHEAST CONUS. THUS...CENTRAL
PA MAY BE DEALING WITH DAILY RING OF FIRE CONVECTION...AND MODELS
HINT AT THIS. TOUGH TO KEEP ANY PARTICULAR PERIOD DRY...BUT MUCH OF
THE TIME WILL NOT BE VERY WET EITHER...JUST A TOUGH PATTERN TO
PINPOINT SPECIFIC SHORTWAVES/WEAK FORCING THIS FAR IN ADVANCE.
ANOTHER TROUGH DROPS SE ACROSS THE GLAKES FOR FRIDAY...WITH POPS
AGAIN INCREASING BEFORE COOLER AND DRIER AIR MOVES IN FOR NEXT
WEEKEND.
OVERNIGHT LOWS WILL AVERAGE ABOVE NORMAL THRU THE EXTENDED
FCST...AS WE REMAIN UNDER PLUME OF ABOVE NORMAL HUMIDITY/PWATS. ENS
MEAN 8H TEMPS INDICATE DAYTIME TEMPS WILL AVERAGE CLOSE TO NORMAL
WITH HIGH MAINLY IN THE 80S...WITH SAT/TUE/WED AS THE WARMEST DAYS
WHILE INCREASED CLOUDS TEMPER HIGHS A BIT ON OTHER DAYS.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL PREVAIL THE MAJORITY OF THE TIME THROUGH THE
TAF PERIOD. SCT CONVECTION WILL BRING LOCAL RESTRICTIONS TO MAINLY
WESTERN TAFS LATE THIS AFTERNOON AND EARLY EVENING.
SOME FOG/HAZE LIKELY OVERNIGHT IN LOWER SUSQ AS HUMID CONDITIONS
PERSIST UNDER INFLUENCE OF BERMUDA HIGH.
THE PATTERN STAYS VERY SIMILAR THROUGH THE NEXT FEW DAYS. PERHAPS
A SHOWER OR THUNDERSTORM...MAINLY IN THE NW...WHERE THE MTS CAN
HELP WITH STORM INITIATION. OTHERWISE...THE BIG UPPER RIDGE WILL
HELP TO SUPPRESS CONVECTION IN THE EAST. WINDS MORE SW NOW THAN
WHAT WE HAD BACK EARLIER IN THE WEEK. NEED MORE OF A SE WIND HERE
FOR WIDESPREAD SHOWERS AND STORMS.
OUTLOOK...
SAT-TUE...PATCHY FOG AM...ISOLD/SCT TSRA - MAINLY IN THE AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/RXR
NEAR TERM...LAMBERT/RXR
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
738 AM EDT FRI JUL 5 2013
.SYNOPSIS...
A BERMUDA HIGH WILL CONTINUE TO FUNNEL VERY WARM AND HUMID AIR NORTH
INTO THE COMMONWEALTH THROUGH THE UPCOMING WEEKEND AS IT REMAINS
ANCHORED OFF THE EASTERN SEABOARD. SCATTERED AFTERNOON AND EARLY
EVENING THUNDERSTORMS WILL DEVELOP TODAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 11 AM THIS MORNING/...
REGIONAL IR SATELLITE IMAGERY SHOWS JUST SOME PATCHES OF STRATO CU
AND CIRRUS DRIFTING NE ACROSS THE REGION EARLY TODAY.
THE REST OF THE MORNING HOURS WILL BE CLEAR TO PARTLY CLOUDY WITH
JUST SOME PATCHES OF HIGH CLOUDS DRIFTING NE...ALONG WITH MUGGY
CONDITIONS WITH A LIGHT SOUTH TO SOUTHWEST BREEZE AND LOW TEMPS
AROUND SUNRISE IN THE UPPER 60S /WESTERN MTNS/ TO LOWER 70S /SUSQ
VALLEY/.
SOME PATCHY 3-5SM FOG WILL LIKELY DEVELOP IN THE DEEPER VALLEYS...
ESPECIALLY ACROSS THE NRN MTNS OF THE STATE.
&&
.SHORT TERM /11 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE BULK OF TODAY LOOKS VERY SIMILAR TO THE LAST COUPLE OF
DAYS...WHICH IS - VERY WARM TO TO HOT...WITH MODERATE TO HIGH
HUMIDITY /SFC DEWPOINTS BETWEEN 65-70F/.
HIGH RES MODELS SUCH AS THE 4KM NAM...AND THE HRRR TARGET THE
CENTRAL AND NW MTNS FOR THE DEVELOPMENT OF SCT TSRA...AND POSSIBLY
EVEN A FEW SLOW-MOVING/TRAINING BKN LINE BETWEEN ABOUT 21Z AND 04Z.
GIVEN THE HIGH PWAT AIR OF NEARLY 2 INCHES ACROSS CENTRAL AND WRN
PENN LATER THIS AFTERNOON AND EVENING. ANY OF THESE STORMS COULD
DUMP VERY HEAVY RAIN OF 1-2 INCHES IN A SHORT AMOUNT OF TIME.
LARGE SCALE...DEEP SUBSIDENCE AND WARMER MID LEVEL TEMPS ON THE NW
EDGE OF THE BERMUDA HIGH WILL LIKELY KEEP THE REGION NEAR...AND TO
THE SE OF INTERSTATE 81 RAIN-FREE DURING THIS PERIOD.
EXPECT HIGH TEMPS VERY SIMILAR TO THURSDAY...AROUND 80F ACROSS THE
HIGHER TERRAIN OF THE NORTH AND WEST...TO AROUND 90F IN THE
SUSQUEHANNA VALLEY.
THE DEEP PLUME OF MOISTURE /WITH ITS ORIGIN FROM THE
PACIFIC...GOMEX...CARIBBEAN AND ATLANTIC/ AND WESTERN PORTION OF THE
RING OF FIRE WILL MAKE VERY LITTLE HEADWAY EAST FROM THE OHIO VALLEY
TODAY AND SATURDAY...SO EXPECTED BROAD-SCALE CONDITIONS /AND FINER
SCALE CONVECTIVE COVERAGE DURING THE AFTERNOON AND EVENING/ TO BE
QUITE SIMILAR TO TODAY /FRIDAY/.
MOST LOCATIONS WILL ONCE AGAIN SEE LITTLE IN THE WAY OF RAIN WITH
PERHAPS 0.10-0.25 BASIN AVERAGE RAINFALL. LOCALIZED...VERY HEAVY
RAIN OF 1-2 INCHES IN UNDER ONE HOUR IS POSSIBLE WITH TRAINING
CELLS...OR STORMS BECOMING ANCHORED TO SOME OF THE FAVORABLE
UPSLOPE FLOW IN THE THE HIGH TERRAIN OF THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MED RANGE GUIDANCE REMAINS IN RELATIVELY GOOD AGREEMENT WITH
RESPECT TO LG SCALE PATTERN INTO EARLY NEXT WEEK...ALL SHOWING CUT
OFF LOW OVR THE MISS VALLY OPENING UP AND LIFTING ACROSS PA ON
SUNDAY OR EARLY MONDAY. AS THIS SYSTEM EDGES CLOSER TO PA...ASSOC
DEEP SOUTHERLY FLOW OF HIGH PWATS /NEARLY 2 INCHES AND PLUS 2-3
SIGMA/ AND INCREASING SWRLY LOW-MID LEVEL SHEAR SHIFTS FROM THE OHIO
VALLEY TO PA ON SATURDAY. THUS...INCREASED CHC OF DIURNALLY-ENHANCED
CONVECTION SAT PM. THE CHC OF CONVECTION REMAINS RELATIVELY HIGH
SUNDAY/MONDAY WITH PASSAGE OF UPPER TROF. EVEN INTO EARLY NEXT WEEK
AS FLOW FLATTENS OUT...PA WILL REMAIN ON NORTHERN PERIPHERY OF
SUBTROPICAL RIDGE CENTERED OVR THE SOUTHEAST CONUS. THUS...CENTRAL
PA MAY BE DEALING WITH DAILY RING OF FIRE CONVECTION...AND MODELS
HINT AT THIS. TOUGH TO KEEP ANY PARTICULAR PERIOD DRY...BUT MUCH OF
THE TIME WILL NOT BE VERY WET EITHER...JUST A TOUGH PATTERN TO
PINPOINT SPECIFIC SHORTWAVES/WEAK FORCING THIS FAR IN ADVANCE.
ANOTHER TROUGH DROPS SE ACROSS THE GLAKES FOR FRIDAY...WITH POPS
AGAIN INCREASING BEFORE COOLER AND DRIER AIR MOVES IN FOR NEXT
WEEKEND.
OVERNIGHT LOWS WILL AVERAGE ABOVE NORMAL THRU THE EXTENDED
FCST...AS WE REMAIN UNDER PLUME OF ABOVE NORMAL HUMIDITY/PWATS. ENS
MEAN 8H TEMPS INDICATE DAYTIME TEMPS WILL AVERAGE CLOSE TO NORMAL
WITH HIGH MAINLY IN THE 80S...WITH SAT/TUE/WED AS THE WARMEST DAYS
WHILE INCREASED CLOUDS TEMPER HIGHS A BIT ON OTHER DAYS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A LITTLE FOG AT BFD...BUT NOTHING ELSEWHERE. SHOULD BURN OFF
SOON.
NOT SEEING MUCH FOG...EVEN WITH HIGH DEWPOINTS. AIRMASS IS VERY
CLEAN...AND TEMPS QUITE HIGH FOR THIS TIME OF MORNING.
THE PATTERN STAYS VERY SIMILAR THROUGH THE NEXT FEW DAYS. PERHAPS
A SHOWER OR THUNDERSTORM...MAINLY IN THE NW...WHERE THE MTS CAN
HELP WITH STORM INITIATION. OTHERWISE...THE BIG UPPER RIDGE WILL
HELP TO SUPPRESS CONVECTION IN THE EAST. WINDS MORE SW NOW THAN
WHAT WE HAD BACK EARLIER IN THE WEEK. NEED MORE OF A SE WIND HERE
FOR WIDESPREAD SHOWERS AND STORMS.
OUTLOOK...
SAT-TUE...PATCHY FOG AM...ISOLD/SCT TSRA - MAINLY IN THE AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
626 AM EDT FRI JUL 5 2013
.SYNOPSIS...
A BERMUDA HIGH WILL CONTINUE TO FUNNEL VERY WARM AND HUMID AIR NORTH
INTO THE COMMONWEALTH THROUGH THE UPCOMING WEEKEND AS IT REMAINS
ANCHORED OFF THE EASTERN SEABOARD. SCATTERED AFTERNOON AND EARLY
EVENING THUNDERSTORMS WILL DEVELOP TODAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 11 AM THIS MORNING/...
REGIONAL IR SATELLITE IMAGERY SHOWS JUST SOME PATCHES OF STRATO CU
AND CIRRUS DRIFTING NE ACROSS THE REGION EARLY TODAY.
THE REST OF THE MORNING HOURS WILL BE CLEAR TO PARTLY CLOUDY WITH
JUST SOME PATCHES OF HIGH CLOUDS DRIFTING NE...ALONG WITH MUGGY
CONDITIONS WITH A LIGHT SOUTH TO SOUTHWEST BREEZE AND LOW TEMPS
AROUND SUNRISE IN THE UPPER 60S /WESTERN MTNS/ TO LOWER 70S /SUSQ
VALLEY/.
SOME PATCHY 3-5SM FOG WILL LIKELY DEVELOP IN THE DEEPER VALLEYS...
ESPECIALLY ACROSS THE NRN MTNS OF THE STATE.
&&
.SHORT TERM /11 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE BULK OF TODAY LOOKS VERY SIMILAR TO THE LAST COUPLE OF
DAYS...WHICH IS - VERY WARM TO TO HOT...WITH MODERATE TO HIGH
HUMIDITY /SFC DEWPOINTS BETWEEN 65-70F/.
HIGH RES MODELS SUCH AS THE 4KM NAM...AND THE HRRR TARGET THE
CENTRAL AND NW MTNS FOR THE DEVELOPMENT OF SCT TSRA...AND POSSIBLY
EVEN A FEW SLOW-MOVING/TRAINING BKN LINE BETWEEN ABOUT 21Z AND 04Z.
GIVEN THE HIGH PWAT AIR OF NEARLY 2 INCHES ACROSS CENTRAL AND WRN
PENN LATER THIS AFTERNOON AND EVENING. ANY OF THESE STORMS COULD
DUMP VERY HEAVY RAIN OF 1-2 INCHES IN A SHORT AMOUNT OF TIME.
LARGE SCALE...DEEP SUBSIDENCE AND WARMER MID LEVEL TEMPS ON THE NW
EDGE OF THE BERMUDA HIGH WILL LIKELY KEEP THE REGION NEAR...AND TO
THE SE OF INTERSTATE 81 RAIN-FREE DURING THIS PERIOD.
EXPECT HIGH TEMPS VERY SIMILAR TO THURSDAY...AROUND 80F ACROSS THE
HIGHER TERRAIN OF THE NORTH AND WEST...TO AROUND 90F IN THE
SUSQUEHANNA VALLEY.
THE DEEP PLUME OF MOISTURE /WITH ITS ORIGIN FROM THE
PACIFIC...GOMEX...CARIBBEAN AND ATLANTIC/ AND WESTERN PORTION OF THE
RING OF FIRE WILL MAKE VERY LITTLE HEADWAY EAST FROM THE OHIO VALLEY
TODAY AND SATURDAY...SO EXPECTED BROAD-SCALE CONDITIONS /AND FINER
SCALE CONVECTIVE COVERAGE DURING THE AFTERNOON AND EVENING/ TO BE
QUITE SIMILAR TO TODAY /FRIDAY/.
MOST LOCATIONS WILL ONCE AGAIN SEE LITTLE IN THE WAY OF RAIN WITH
PERHAPS 0.10-0.25 BASIN AVERAGE RAINFALL. LOCALIZED...VERY HEAVY
RAIN OF 1-2 INCHES IN UNDER ONE HOUR IS POSSIBLE WITH TRAINING
CELLS...OR STORMS BECOMING ANCHORED TO SOME OF THE FAVORABLE
UPSLOPE FLOW IN THE THE HIGH TERRAIN OF THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MED RANGE GUIDANCE REMAINS IN RELATIVELY GOOD AGREEMENT WITH
RESPECT TO LG SCALE PATTERN INTO EARLY NEXT WEEK...ALL SHOWING CUT
OFF LOW OVR THE MISS VALLY OPENING UP AND LIFTING ACROSS PA ON
SUNDAY OR EARLY MONDAY. AS THIS SYSTEM EDGES CLOSER TO PA...ASSOC
DEEP SOUTHERLY FLOW OF HIGH PWATS /NEARLY 2 INCHES AND PLUS 2-3
SIGMA/ AND INCREASING SWRLY LOW-MID LEVEL SHEAR SHIFTS FROM THE OHIO
VALLEY TO PA ON SATURDAY. THUS...INCREASED CHC OF DIURNALLY-ENHANCED
CONVECTION SAT PM. THE CHC OF CONVECTION REMAINS RELATIVELY HIGH
SUNDAY/MONDAY WITH PASSAGE OF UPPER TROF. EVEN INTO EARLY NEXT WEEK
AS FLOW FLATTENS OUT...PA WILL REMAIN ON NORTHERN PERIPHERY OF
SUBTROPICAL RIDGE CENTERED OVR THE SOUTHEAST CONUS. THUS...CENTRAL
PA MAY BE DEALING WITH DAILY RING OF FIRE CONVECTION...AND MODELS
HINT AT THIS. TOUGH TO KEEP ANY PARTICULAR PERIOD DRY...BUT MUCH OF
THE TIME WILL NOT BE VERY WET EITHER...JUST A TOUGH PATTERN TO
PINPOINT SPECIFIC SHORTWAVES/WEAK FORCING THIS FAR IN ADVANCE.
ANOTHER TROUGH DROPS SE ACROSS THE GLAKES FOR FRIDAY...WITH POPS
AGAIN INCREASING BEFORE COOLER AND DRIER AIR MOVES IN FOR NEXT
WEEKEND.
OVERNIGHT LOWS WILL AVERAGE ABOVE NORMAL THRU THE EXTENDED
FCST...AS WE REMAIN UNDER PLUME OF ABOVE NORMAL HUMIDITY/PWATS. ENS
MEAN 8H TEMPS INDICATE DAYTIME TEMPS WILL AVERAGE CLOSE TO NORMAL
WITH HIGH MAINLY IN THE 80S...WITH SAT/TUE/WED AS THE WARMEST DAYS
WHILE INCREASED CLOUDS TEMPER HIGHS A BIT ON OTHER DAYS.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A LITTLE FOG AT BFD...BUT NOTHING ELSEWHERE.
NOT SEEING MUCH FOG...EVEN WITH HIGH DEWPOINTS. AIRMASS VERY
CLEAN...AND TEMPS QUITE HIGH STILL FOR THIS TIME OF MORNING.
THE PATTERN STAYS VERY SIMILAR THROUGH THE NEXT FEW DAYS. PERHAPS
A SHOWER OR THUNDERSTORM...MAINLY IN THE NWRN HALF OF THE AREA
WHERE THE MTS CAN HELP WITH STORM INITIATION. OTHERWISE...THE BIG
UPPER RIDGE WILL HELP TO SUPPRESS CONVECTION IN THE EAST. WINDS
MORE SW NOW THAN WHAT WE HAD BACK EARLIER IN THE WEEK. NEED MORE
OF A SE WIND HERE FOR WIDESPREAD SHOWERS AND STORMS.
OUTLOOK...
SAT-TUE...PATCHY FOG AM...ISOLD/SCT TSRA - MAINLY IN THE AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
510 AM EDT FRI JUL 5 2013
.SYNOPSIS...
A BERMUDA HIGH WILL CONTINUE TO FUNNEL VERY WARM AND HUMID AIR NORTH
INTO THE COMMONWEALTH THROUGH THE UPCOMING WEEKEND AS IT REMAINS
ANCHORED OFF THE EASTERN SEABOARD. SCATTERED AFTERNOON AND EARLY
EVENING THUNDERSTORMS WILL DEVELOP TODAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 11 AM THIS MORNING/...
REGIONAL IR SATELLITE IMAGERY SHOWS JUST SOME PATCHES OF STRATO CU
AND CIRRUS DRIFTING NE ACROSS THE REGION EARLY TODAY.
THE REST OF THE MORNING HOURS WILL BE CLEAR TO PARTLY CLOUDY WITH
JUST SOME PATCHES OF HIGH CLOUDS DRIFTING NE...ALONG WITH MUGGY
CONDITIONS WITH A LIGHT SOUTH TO SOUTHWEST BREEZE AND LOW TEMPS
AROUND SUNRISE IN THE UPPER 60S /WESTERN MTNS/ TO LOWER 70S /SUSQ
VALLEY/.
SOME PATCHY 3-5SM FOG WILL LIKELY DEVELOP IN THE DEEPER VALLEYS...
ESPECIALLY ACROSS THE NRN MTNS OF THE STATE.
&&
.SHORT TERM /11 AM THIS MORNING THROUGH 6 PM SATURDAY/...
THE BULK OF TODAY LOOKS VERY SIMILAR TO THE LAST COUPLE OF
DAYS...WHICH IS - VERY WARM TO TO HOT...WITH MODERATE TO HIGH
HUMIDITY /SFC DEWPOINTS BETWEEN 65-70F/.
HIGH RES MODELS SUCH AS THE 4KM NAM...AND THE HRRR TARGET THE
CENTRAL AND NW MTNS FOR THE DEVELOPMENT OF SCT TSRA...AND POSSIBLY
EVEN A FEW SLOW-MOVING/TRAINING BKN LINE BETWEEN ABOUT 21Z AND 04Z.
GIVEN THE HIGH PWAT AIR OF NEARLY 2 INCHES ACROSS CENTRAL AND WRN
PENN LATER THIS AFTERNOON AND EVENING. ANY OF THESE STORMS COULD
DUMP VERY HEAVY RAIN OF 1-2 INCHES IN A SHORT AMOUNT OF TIME.
LARGE SCALE...DEEP SUBSIDENCE AND WARMER MID LEVEL TEMPS ON THE NW
EDGE OF THE BERMUDA HIGH WILL LIKELY KEEP THE REGION NEAR...AND TO
THE SE OF INTERSTATE 81 RAIN-FREE DURING THIS PERIOD.
EXPECT HIGH TEMPS VERY SIMILAR TO THURSDAY...AROUND 80F ACROSS THE
HIGHER TERRAIN OF THE NORTH AND WEST...TO AROUND 90F IN THE
SUSQUEHANNA VALLEY.
THE DEEP PLUME OF MOISTURE /WITH ITS ORIGIN FROM THE
PACIFIC...GOMEX...CARIBBEAN AND ATLANTIC/ AND WESTERN PORTION OF THE
RING OF FIRE WILL MAKE VERY LITTLE HEADWAY EAST FROM THE OHIO VALLEY
TODAY AND SATURDAY...SO EXPECTED BROAD-SCALE CONDITIONS /AND FINER
SCALE CONVECTIVE COVERAGE DURING THE AFTERNOON AND EVENING/ TO BE
QUITE SIMILAR TO TODAY /FRIDAY/.
MOST LOCATIONS WILL ONCE AGAIN SEE LITTLE IN THE WAY OF RAIN WITH
PERHAPS 0.10-0.25 BASIN AVERAGE RAINFALL. LOCALIZED...VERY HEAVY
RAIN OF 1-2 INCHES IN UNDER ONE HOUR IS POSSIBLE WITH TRAINING
CELLS...OR STORMS BECOMING ANCHORED TO SOME OF THE FAVORABLE UPSLOPE
FLOW IN THE THE HIGH TERRAIN OF THE WEST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MED RANGE GUIDANCE REMAINS IN RELATIVELY GOOD AGREEMENT WITH
RESPECT TO LG SCALE PATTERN INTO EARLY NEXT WEEK...ALL SHOWING CUT
OFF LOW OVR THE MISS VALLY OPENING UP AND LIFTING ACROSS PA ON
SUNDAY OR EARLY MONDAY. AS THIS SYSTEM EDGES CLOSER TO PA...ASSOC
DEEP SOUTHERLY FLOW OF HIGH PWATS /NEARLY 2 INCHES AND PLUS 2-3
SIGMA/ AND INCREASING SWRLY LOW-MID LEVEL SHEAR SHIFTS FROM THE OHIO
VALLEY TO PA ON SATURDAY. THUS...INCREASED CHC OF DIURNALLY-ENHANCED
CONVECTION SAT PM. THE CHC OF CONVECTION REMAINS RELATIVELY HIGH
SUNDAY/MONDAY WITH PASSAGE OF UPPER TROF. EVEN INTO EARLY NEXT WEEK
AS FLOW FLATTENS OUT...PA WILL REMAIN ON NORTHERN PERIPHERY OF
SUBTROPICAL RIDGE CENTERED OVR THE SOUTHEAST CONUS. THUS...CENTRAL
PA MAY BE DEALING WITH DAILY RING OF FIRE CONVECTION...AND MODELS
HINT AT THIS. TOUGH TO KEEP ANY PARTICULAR PERIOD DRY...BUT MUCH OF
THE TIME WILL NOT BE VERY WET EITHER...JUST A TOUGH PATTERN TO
PINPOINT SPECIFIC SHORTWAVES/WEAK FORCING THIS FAR IN ADVANCE.
ANOTHER TROUGH DROPS SE ACROSS THE GLAKES FOR FRIDAY...WITH POPS
AGAIN INCREASING BEFORE COOLER AND DRIER AIR MOVES IN FOR NEXT
WEEKEND.
OVERNIGHT LOWS WILL AVERAGE ABOVE NORMAL THRU THE EXTENDED
FCST...AS WE REMAIN UNDER PLUME OF ABOVE NORMAL HUMIDITY/PWATS. ENS
MEAN 8H TEMPS INDICATE DAYTIME TEMPS WILL AVERAGE CLOSE TO NORMAL
WITH HIGH MAINLY IN THE 80S...WITH SAT/TUE/WED AS THE WARMEST DAYS
WHILE INCREASED CLOUDS TEMPER HIGHS A BIT ON OTHER DAYS.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
NOT SEEING MUCH POTENTIAL FOR FOG OVERNIGHT...EVEN WITH HIGH
DEWPOINTS. AIRMASS VERY CLEAN...AND TEMPS QUITE HIGH STILL FOR
THIS TIME OF NIGHT.
THE PATTERN STAYS VERY SIMILAR THROUGH THE NEXT FEW DAYS.
PERHAPS A SHOWER OR THUNDERSTORM...MAINLY IN THE NWRN HALF OF THE
AREA WHERE THE MTS CAN HELP WITH STORM INITIATION. OTHERWISE...THE
BIG UPPER RIDGE WILL HELP TO SUPPRESS CONVECTION IN THE EAST. WINDS
MORE SW NOW THAN WHAT WE HAD BACK EARLIER IN THE WEEK. NEED MORE
OF A SE WIND HERE FOR WIDESPREAD SHOWERS AND STORMS.
OUTLOOK...
SAT-TUE...PATCHY FOG AM...ISOLD/SCT TSRA - MAINLY IN THE AFTN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...GARTNER/MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
217 AM EDT FRI JUL 5 2013
.SYNOPSIS...
A DEEP UPPER LEVEL TROUGH WILL REMAIN IN PLACE OVER THE MID
MISSISSIPPI RIVER VALLEY THROUGH TONIGHT...BEFORE GRADUALLY
LIFTING EASTWARD OVER THE WEEKEND. HIGH PRESSURE WILL THEN BUILD
OVER THE SOUTHERN TIER OF THE UNITED STATES NEXT WEEK...WITH A
RETURN TO MORE TYPICAL SUMMERTIME CONDITIONS.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 210 AM...SEVERAL BREAKS HAVE DEVELOPED WITHIN THE HIGH CLOUD
COVER. CONDITIONS UNDER THE CLEARING BANDS OR PATCHES MAY RAPIDLY
DEVELOP FOG AND LOW CLOUDS. I WILL UPDATE THE FORECAST TO ADJUST SKY
AND FOG TIMING. IN ADDITION...SHOWERS CONTINUE TO DEVELOP ACROSS THE
CWA...ESPECIALLY OVER THE FOOTHILLS AND EAST FACING SLOPES. I WILL
ADJUST POPS AND DECREASE MENTION OF TSRA FOR THE REST OF THE NIGHT.
AS OF 1030 PM...ANOTHER UPDATE...MAINLY TO THE POPS FOR THE
OVERNIGHT. THE OVERALL TRENDS HAVE BEEN DOWNWARD IN COVERAGE AND
INTENSITY OF THE RAIN...WHICH IS GOOD NEWS. THE 00Z FFC SOUNDING
SHOWS THE 45-50 KT LLJ...WHICH WAS INITIALIZED WELL ON THE RAP AND
NAM. THEY TAKE THE JET DUE NORTH INTO ERN TN. SO PERHAPS LESS
UPSLOPE AND HIGH ELEV WIND THREAT WILL EXIST OVERNIGHT. STILL EXPECT
AT LEAST SCATTERED TO NUMEROUS SHWRS THRU THE NIGHT...BUT PERHAPS A
LULL IN THE FLASH FLOOD THREAT...BEFORE ANOTHER ROUND WITH HEATING
ON FRIDAY.
AS OF 800 PM...THE PLUME OF MOISTURE AND ASSOCIATED BANDS OF MOD-HVY
RAIN HAS SHIFTED SLIGHTLY WEST TODAY...AND GUIDANCE IN GOOD
AGREEMENT ON THIS TREND CONTINUING OVERNIGHT. SO WHILE A FEW AREAS
OF SHOWERS AND TSTMS STILL POSSIBLE ACRS THE I-77 CORRIDOR...STILL
FEEL OKAY WITH ALLOWING THE FLASH FLOOD WATCH TO EXPIRE THERE.
ELSEWHERE...THE FLOOD THREAT CONTINUES...WITH NUMEROUS WARNINGS AND
ADVISORIES IN EFFECT ATTM. THE CATEGORICAL POPS WITH HEAVY RAIN
WORDING STILL ON TRACK FOR TONIGHT.
AS OF 445 PM...A QUICK UPDATE TO THE TEMP/DEWPT AND SKY GRIDS TO
MATCH UP WITH OBS. POPS/WX LOOK ON TRACK...SO LEFT AS IS FOR NOW.
AS OF 300 PM...NOT MUCH HAS CHANGED IN REGARDS TO THE FORECAST OVER
THE NEXT 24 HOURS. SOUTHERLY FLOW WILL PROMOTE CONTINUED SHOWER AND
THUNDERSTORM ACTIVITY ACROSS THE ENTIRE REGION. HEAVY RAINFALL LOOKS
TO BE THE MAIN THREAT THROUGH THE PERIOD. RAINFALL AMOUNTS
ADJACENT TO ANY THUNDERSTORMS COULD EXCEED 5 INCHES WHICH WILL ALLOW
FOR FLASH FLOODING CONDITIONS TO PERSIST. THIS FLASH FLOODING
THREAT WILL MAINLY EXIST ACROSS THE HIGHER TERRAINS AND THE
FOOTHILLS DUE TO UPSLOPE FLOW AND MIGRATION OF MOISTURE AXIS TO THE
WEST. OTHERWISE...INCREASING INSTABILITY ACROSS PORTIONS OF THE SC
UPSTATE AND THE NC PIEDMONT WILL ALLOW FOR SOME STRONG TO SEVERE
THUNDERSTORMS WITH DAMAGING WINDS...AND HEAVY RAINFALL BEING THE
MAIN THREATS. DUE TO INCREASING FLOW ALOFT...AND BACKED SURFACE
WINDS...AN ISOLATED TORNADO CANNOT BE RULED OUT. CONDITIONS WILL
NOT IMPROVE MUCH DURING THE OVERNIGHT HOURS AS PLUME OF MOISTURE
REMAINS NEARLY STATIONARY ACROSS THE WESTERN PART OF THE CWFA.
THUS...EXTENDED FLASH FLOOD WATCH THROUGH 00Z SATURDAY ACROSS ALL
ZONES WITH THE ONLY EXCEPTIONS BEING ACROSS PORTIONS OF THE NC
PIEDMONT. TEMPERATURES OVERNIGHT WILL BE NEAR NORMAL FOR MOST SITES.
FOR FRIDAY...EXPECT MUCH OF THE SAME AS THURSDAY WITH CONTINUED
RAINFALL ACROSS THE WESTERN MOST PORTIONS OF THE REGION.
INSTABILITY WILL INCREASE YET AGAIN...HOWEVER CONVECTION SHOULD BE
ON MORE OF A DIURNAL TREND. HIGH TEMPERATURES ON FRIDAY WILL BE
BELOW NORMAL AT ALL LOCATIONS.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 230 PM THURSDAY...THE SLOWLY FILLING UPPER WAVE WILL LIFT NE
ACROSS IL/IN ON SAT AND THEN OH ON SUNDAY. UPPER LEVEL DYNAMICS IN
THE FORM OF WIND DIVERGENCE AND A TRAILING VORTICITY AXIS WILL CROSS
OUR FORECAST AREA ON SUNDAY. UNTIL THEN...PERSISTENT MOIST SRLY LOW
LEVEL FLOW WILL CONTINUE. WILL FOCUS LIKELY POPS IN THE MTNS...AND
TAPER DOWN TO MID RANGE CHANCE ACROSS THE PIEDMONT FOR SAT AFTN.
COVERAGE MAY REBOUND THROUGHOUT THE REGION A BIT ON SUNDAY WITH THE
PASSING UPPER SUPPORT. THE THREAT OF HEAVY RAIN AND ISOLATED FLASH
FLOODING WILL CONTINUE THROUGH THE WEEKEND.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 230 PM THURSDAY...A FLAT RIDGE WILL BUILD OVER THE SRN TIER OF
THE CONUS MON THROUGH WED. SFC HIGH PRES WILL DOMINATE EXCEPT FOR A
DEVELOPING LEE TROUGH OVER THE PIEDMONT. MID LEVEL DRYING IS
INDICATED...BUT LOW LEVELS WILL REMAIN MOIST THROUGH THE PERIOD. SFC
TO 850 MB FLOW WILL VEER MORE WESTERLY TO CURB PRECIPITATION CHANCES
AND PRODUCE MORE OF A DIURNAL TREND IN POPS. A COLD FRONT WILL
APPROACH THE AREA FROM THE NW ON THU. EXPECT MAX TEMPS TO RECOVER TO
NEAR SUMMERTIME NORMALS.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AT KCLT...AT 6Z...CLT AND SURROUNDING TERMINALS WERE OBSERVING IFR
CEILINGS WITH LVFR TO MVFR VIS IN BR. THE LOW CEILINGS WERE
DEVELOPING UNDER BREAKS IN THE HIGHER CLOUDS. RECENT SATE IMAGES
INDICATE THAT BREAKS MAY WIDEN AND PERSIST THROUGH THE NEXT SEVERAL
HOURS. GIVEN THE SATURATED SOIL CONDITIONS AND LIGHT
WINDS...CONDITIONS WITHIN THE CLEARING SKY COVER ARE VERY SUITABLE
FOR INCREASE RESTRICTIONS EARLY THIS MORNING. RECENT MORNING TRENDS
AND FORECAST SOUNDINGS INDICATE THAT CEILINGS WILL LIFT FROM IFR
AROUND SUNRISE TO MVFR BY MID MORNING. DURING THE EARLY TO MID
AFTERNOON...CEILINGS MAY BREAK AND LIFT TO VFR. SHRA AND TSRA WILL
BE HIGHLIGHTED DURING THE PEAK HEATING HOURS USING A PROB30 BETWEEN
17 TO 20Z. WINDS SHOULD REMAIN FROM THE SSE BETWEEN 5 TO 10 KTS
THROUGH THE TAF PERIOD.
ELSEWHERE...AT 6Z...HIGH CLOUDS REMAINED OVER KAVL AND KAND...WITH
KGMU/KGSP ON THE EDGE OF THE HIGHER CLOUDS. CONDITIONS UNDER THE
HIGHER CLOUD COVER RANGED FROM VFR TO MVFR. BREAKS IN THE HIGHER
CLOUDS OVER KHKY AND NEAR KGSP HAVE SUPPORTED IFR CEILINGS AND LARGE
RANGES IN VIS. SATELLITE TRENDS INDICATE THAT HOLES OR BANDS OF
CLEARING WILL LIKELY CONTINUE THROUGH THE REST OF THE NIGHT. I WOULD
EXPECT THAT IFR CEILINGS WILL DEVELOP SHORTLY AFTER ANY CLEARING.
THEREFORE...I WILL FAVOR AT LEAST IFR DURING THE PRE DAWN TO DAWN
HOURS. RECENT MORNING TRENDS AND FORECAST SOUNDINGS INDICATE THAT
CEILINGS WILL LIFT FROM IFR AROUND SUNRISE TO MVFR BY MID MORNING.
DURING THE EARLY TO MID AFTERNOON...CEILINGS MAY BREAK AND LIFT TO
VFR. SHRA AND TSRA WILL BE HIGHLIGHTED DURING THE PEAK HEATING HOURS
USING A PROB30 EAST OF THE MTNS. WINDS SHOULD REMAIN FROM THE SSE
BETWEEN 5 TO 10 KTS THROUGH THE TAF PERIOD.
OUTLOOK...VERY MOIST AND UNSETTLED CONDITIONS WILL REMAIN OVER THE
REGION INTO SATURDAY...WITH PERIODS OF SHRA/TSRA. STRATUS AND FOG IS
POSSIBLE EACH NIGHT ACROSS THE REGION. GRADUAL IMPROVEMENT IS
EXPECTED FROM THE EAST THIS WEEKEND AS A BERMUDA HIGH STRENGTHENS
ACROSS THE REGION...YIELDING MAINLY DIURNAL SHRA/TSRA. MORNING FOG
WILL FAVOR THE MTN VALLEYS.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT MED 72% HIGH 83% HIGH 100% HIGH 100%
KGSP MED 75% MED 75% HIGH 93% HIGH 95%
KAVL MED 75% MED 78% HIGH 89% HIGH 90%
KHKY MED 61% MED 77% HIGH 100% HIGH 97%
KGMU MED 69% MED 68% HIGH 90% HIGH 95%
KAND MED 71% MED 67% HIGH 97% HIGH 95%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR GAZ010-017-018-026-
028-029.
NC...FLASH FLOOD WATCH THROUGH THIS EVENING FOR NCZ033-035-048>053-
056-058-059-062>065-068>070-501>510.
SC...FLASH FLOOD WATCH THROUGH THIS EVENING FOR SCZ001>014-019.
&&
$$
SYNOPSIS...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1259 PM CDT FRI JUL 5 2013
.UPDATE...FOR 18Z AVIATION FORECAST
&&
.AVIATION...
CONVECTION HAS DEVELOPED IN A BAND FROM LAWRENCEBURG NORTHEAST
THROUGH THE NASHVILLE AREA INTO KENTUCKY AROUND LAKE CUMBERLAND.
LOOK FOR SHOWERS AND THUNDERSTORMS TO BECOME MORE NUMEROUS AS WE
GO THROUGH THE AFTERNOON AND CONTINUE TONIGHT. AM EXPECTING POOR
FLYING WEATHER FOR THE NEXT 24 HOURS AND BEYOND HERE IN THE MID
STATE DUE TO LOW CEILINGS AND VISIBILITIES WITH NUMEROUS SHOWERS
AND THUNDERSTORMS AFFECTING THE AREA.
BOYD
&&
.PREV DISCUSSION... /ISSUED 1124 AM CDT FRI JUL 5 2013/
UPDATE...
LATEST RADAR IMAGERY SHOWS SCATTERED LIGHT SHOWERS STREAMING
NORTHWARD ACROSS THE MID STATE. WIDESPREAD CLOUD COVER AND PRECIP
IS KEEPING TEMPS DOWN AND HAVE LOWERED HIGH TEMPS A TAD.
ALSO...12Z OHX SOUNDING SHOWED A VERY SATURATED ATMOSPHERE IN
PLACE WITH A PWAT OF 1.81 INCHES. THUS LIGHTNING WILL BE HARD TO
COME BY TODAY SO HAVE LOWERED TSTORM MENTION TO JUST A SLIGHT
CHANCE.
12Z NAM/GFS ALONG WITH LATEST HRRR RUNS SHOWING A BLOSSOMING OF
SHOWERS LATER THIS AFTERNOON AND ESPECIALLY TONIGHT AS UPPER
TROUGH INCHES CLOSER TO US. MODELS ALSO SHOW ADDITIONAL ROUNDS OF
SHOWERS/STORMS OVER THE WEEKEND...ESPECIALLY SATURDAY NIGHT AS
STRONG LIFT DEVELOPS OVER THE MID STATE IN THE DIVERGENT FLOW
SOUTHEAST OF THE UPPER LOW. IN ADDITION...MUCH OF THE WATCH AREA
RECEIVED BETWEEN 1.5 AND 5.5 INCHES OF RAINFALL YESTERDAY...WHICH
HAS LOWERED FFG VALUES BELOW 1 INCH/HR FOR SOME LOCATIONS. HPC
QPF INDICATES AN ADDITIONAL 2 TO 4 INCHES OF RAIN IS POSSIBLE OVER
THE WEEKEND...WHILE RAW GFS/NAM QPF OUTPUT IS EVEN HIGHER ALTHOUGH
CONVECTIVE FEEDBACK IS SKEWING THEIR OUTPUT. EVEN SO...WITH
GROUNDS SATURATED FROM THE RECENT RAINFALL...ANY ADDITIONAL HEAVY
RAINFALL WOULD RESULT IN FLOODING OVER THE WEEKEND. FOR ALL THESE
REASONS HAVE EXTENDED THE FLASH FLOOD WATCH OUT THROUGH SUNDAY
MORNING.
SHAMBURGER
PREV DISCUSSION... /ISSUED 914 AM CDT FRI JUL 5 2013/
SEEING A LULL IN THE RAINFALL ACROSS THE MID STATE AT THIS TIME.
THIS WILL GIVE RIVERS AND CREEKS A CHANCE TO DO THEIR JOB IN
CARRYING OFF THE WATER THAT FELL YESTERDAY AND OVERNIGHT. THINK WE
WILL SEE SCATTERED SHOWERS AS WE GO THROUGH THE MORNING BEGIN TO
INCREASE AND BECOME MORE NUMEROUS ACROSS SOUTHERN AND EASTERN
AREAS OF THE MID STATE BY EARLY AFTERNOON AND EVENTUALLY COVER
JUST ABOUT ALL OF THE MID STATE BY MID AFTERNOON. LOCALLY HEAVY
RAINFALL WILL ONCE AGAIN BE POSSIBLE THAT COULD LEAD TO LOCALIZED
FLASH FLOODING.
BOYD
PREV DISCUSSION... /ISSUED 657 AM CDT FRI JUL 5 2013/
UPDATE...FOR 12Z AVIATION DISCUSSION.
AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...CEILING FLUCTUATIONS BETWEEN VFR TO IFR CEILINGS AND HEAVY
RAINFALL IMPACTS TAF SITES. FOR BRIEFNESS 05/12Z-05/18Z...WILL GO WITH
PREVAILING CONDITIONS BUT STILL EXPECT SOME FLUCTUATIONS POSSIBLE. BELIEVE
BEST CHANCE FOR HEAVY RAINFALL 05/20Z-06/00Z...BUT MODERATE RAINFALL
POTENTIAL SHOULD PERSISTS THRU 06/10Z PER HIGH PRECIP WATER VALUES. EXPECT A
GENERAL LOWERING OF CEILINGS TO MVFR/IFR THRESHOLDS AFTER 06/00Z WITH MORE
PRONOUNCED PATCHY FOG DEVELOPMENT. EXPECT OVERALL LIGHT SLY FLOW THRU 06/12Z
WITH SOME POTENTIAL OF HIGHER GUSTS NEAR TSTMS.
PREV DISCUSSION... /ISSUED 328 AM CDT FRI JUL 5 2013/
STRONG BERMUDA HIGH CENTERED OVER THE WESTERN ATLANTIC WITH AN
UNUSUALLY STRONG MID SUMMER TROUGH OVER THE NATIONS INTERIOR. DEEP
SOUTHERLY FLOW EXISTS BETWEEN THE TWO FEATURES. AT THE SFC...A
WEAKENING N-S STATIONARY FRONTAL BOUNDARY STRETCHES FROM THE WESTERN
GULF NE THROUGH MS AND WESTERN TN.
CURRENTLY...A BRIEF LULL IN THE WET PATTERN IS INDICATED. 850 MB
FLOW IS SLIGHTLY ENHANCED BUT THE DEGREE OF SPEED CONVERGENCE IS
OVERDONE. UPPER TROUGH APPEARS TO BE TOO FAR WEST TO EXPAND ON ANY
UPPER DIVERGENCE ACROSS THE AREA. THUS...THE KEY CATALYST WOULD
NEED TO BE DISTURBANCES WITHIN THE MID/UPPER LEVEL SOUTHERLY FLOW.
LATEST MODELS SUGGEST THE BETTER DISTURBANCES HAVE SHIFTED NORTH
FOR NOW.
FOR TODAY...AIRMASS WILL NEED A LITTLE DAYTIME HEATING TO GET THE
CONVECTION GOING. BUT BY AFTERNOON AND TONIGHT...THE AFOREMENTIONED
UPPER TROUGH WILL BEGIN MOVING EASTWARD WHILE THE ASSOCIATED UPPER
LOW MOVE SOUTHEASTWARD. THIS WILL ALLOW DEEPER MOISTURE TO RETURN
WITH ADDITIONAL DYNAMICS COMING INTO PLAY. THUS...THE LIKELY TO
CATEGORICAL POPS WILL RETURN THIS AFTERNOON AND INTO TONIGHT.
NOW...AS FAR AS THE FLASH FLOOD WATCH GOES...RAINFALL AMOUNTS HAVE
BEEN GENERALLY IN THE 1-2 INCH RANGE SO FAR BUT SCATTERED AREAS
HAVE RECEIVED MUCH MORE. LATEST FFG SUGGEST THAT ONLY AN INCH OR SO
OF RAINFALL IN THE 1-3 HR PERIOD MAY CAUSE FLASH FLOODING.
THUS...WILL ELECT TO KEEP THE FLASH FLOOD WATCH GOING. IT DOES
EXPIRE FRIDAY EVENING(THIS UPCOMING EVENING). WILL ALLOW THE DAY
SHIFT TO DECIDE ON WHETHER OR NOT TO EXTEND THE WATCH.
OTHERWISE...THUS FAR...THE MODELS HAVE TENDED TO BE A LITTLE TOO
AGGRESSIVE WITH THE QPF FROM THIS SYSTEM. THUS...WILL LEAN TOWARD
THE HPC QPF ESTIMATIONS FOR THE QPF GRIDS.
AS WE GO FORWARD IN TIME...THE UPPER TROUGH WILL BE MOVING EASTWARD
WITH THE AXIS CROSSING THE MID STATE ON SUNDAY. IT WILL BE AT THIS
POINT THAT OUR POPS WILL BEGIN TO DECREASE...SETTING THE STAGE FOR A
MORE SUMMER-LIKE PATTERN FOR THE EXTENDED PERIOD.
FOR THE NEAR TERM TEMPS...WITH THE INFLUENCES OF THE UPPER
TROUGH...CLOUDS AND PRECIPITATION...BELOW NORMAL TEMPS WILL CONTINUE
THROUGH SUNDAY. VERSUS THE MAV GUIDANCE...A SLIGHT UNDERCUT OF MAX
VALUES WILL BE INCLUDED.
IN THE EXT FCST...ONCE THE UPPER TROUGH AXIS MOVES EAST...WE WILL
REVERT MORE TOWARD A TYPICAL SUMMERTIME PATTERN. THE BERMUDA HIGH
AND THE UPPER HIGH OVER THE SOUTHERN PLAINS WILL BOTH WEAKEN. THE
WEAKNESS WITHIN THE TWO UPPER LEVEL HIGHS WILL STILL ALLOW
CONVECTION POSSIBILITIES TO CONTINUE...BUT AREAL COVERAGE WILL BE
MUCH LESS THAN WHAT WE ARE SEEING THROUGH MUCH OF THE NEAR TERM
FORECAST.
AS WE MOVE TOWARD THE END OF THE EXT PERIOD...WEAK TROUGHING/NW FLOW
WILL RETURN WITH POPS AND QPF AMOUNTS INCHING UPWARD ONCE AGAIN.
FOR THE EXT TEMPS...VALUES WILL LOOK VERY SEASONAL AS A WEAK W-E
RIDGE PREVAILS AND 850 MB TEMPS RANGE FROM 18C-20C. VERSUS THE
MEX...WILL INCLUDE A SLIGHT UNDERCUT.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR TNZ007>011-026>034-
059>066-075-077>080-094-095.
&&
$$
01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1124 AM CDT FRI JUL 5 2013
.UPDATE...
LATEST RADAR IMAGERY SHOWS SCATTERED LIGHT SHOWERS STREAMING
NORTHWARD ACROSS THE MID STATE. WIDESPREAD CLOUD COVER AND PRECIP
IS KEEPING TEMPS DOWN AND HAVE LOWERED HIGH TEMPS A TAD.
ALSO...12Z OHX SOUNDING SHOWED A VERY SATURATED ATMOSPHERE IN
PLACE WITH A PWAT OF 1.81 INCHES. THUS LIGHTNING WILL BE HARD TO
COME BY TODAY SO HAVE LOWERED TSTORM MENTION TO JUST A SLIGHT
CHANCE.
12Z NAM/GFS ALONG WITH LATEST HRRR RUNS SHOWING A BLOSSOMING OF
SHOWERS LATER THIS AFTERNOON AND ESPECIALLY TONIGHT AS UPPER
TROUGH INCHES CLOSER TO US. MODELS ALSO SHOW ADDITIONAL ROUNDS OF
SHOWERS/STORMS OVER THE WEEKEND...ESPECIALLY SATURDAY NIGHT AS
STRONG LIFT DEVELOPS OVER THE MID STATE IN THE DIVERGENT FLOW
SOUTHEAST OF THE UPPER LOW. IN ADDITION...MUCH OF THE WATCH AREA
RECEIVED BETWEEN 1.5 AND 5.5 INCHES OF RAINFALL YESTERDAY...WHICH
HAS LOWERED FFG VALUES BELOW 1 INCH/HR FOR SOME LOCATIONS. HPC
QPF INDICATES AN ADDITIONAL 2 TO 4 INCHES OF RAIN IS POSSIBLE OVER
THE WEEKEND...WHILE RAW GFS/NAM QPF OUTPUT IS EVEN HIGHER ALTHOUGH
CONVECTIVE FEEDBACK IS SKEWING THEIR OUTPUT. EVEN SO...WITH
GROUNDS SATURATED FROM THE RECENT RAINFALL...ANY ADDITIONAL HEAVY
RAINFALL WOULD RESULT IN FLOODING OVER THE WEEKEND. FOR ALL THESE
REASONS HAVE EXTENDED THE FLASH FLOOD WATCH OUT THROUGH SUNDAY
MORNING.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 914 AM CDT FRI JUL 5 2013/
SEEING A LULL IN THE RAINFALL ACROSS THE MID STATE AT THIS TIME.
THIS WILL GIVE RIVERS AND CREEKS A CHANCE TO DO THEIR JOB IN
CARRYING OFF THE WATER THAT FELL YESTERDAY AND OVERNIGHT. THINK WE
WILL SEE SCATTERED SHOWERS AS WE GO THROUGH THE MORNING BEGIN TO
INCREASE AND BECOME MORE NUMEROUS ACROSS SOUTHERN AND EASTERN
AREAS OF THE MID STATE BY EARLY AFTERNOON AND EVENTUALLY COVER
JUST ABOUT ALL OF THE MID STATE BY MID AFTERNOON. LOCALLY HEAVY
RAINFALL WILL ONCE AGAIN BE POSSIBLE THAT COULD LEAD TO LOCALIZED
FLASH FLOODING.
BOYD
PREV DISCUSSION... /ISSUED 657 AM CDT FRI JUL 5 2013/
UPDATE...FOR 12Z AVIATION DISCUSSION.
AVIATION...12Z AVIATION DISCUSSION.
UNCERTAINTIES...CEILING FLUCTUATIONS BETWEEN VFR TO IFR CEILINGS AND HEAVY
RAINFALL IMPACTS TAF SITES. FOR BRIEFNESS 05/12Z-05/18Z...WILL GO WITH
PREVAILING CONDITIONS BUT STILL EXPECT SOME FLUCTUATIONS POSSIBLE. BELIEVE
BEST CHANCE FOR HEAVY RAINFALL 05/20Z-06/00Z...BUT MODERATE RAINFALL
POTENTIAL SHOULD PERSISTS THRU 06/10Z PER HIGH PRECIP WATER VALUES. EXPECT A
GENERAL LOWERING OF CEILINGS TO MVFR/IFR THRESHOLDS AFTER 06/00Z WITH MORE
PRONOUNCED PATCHY FOG DEVELOPMENT. EXPECT OVERALL LIGHT SLY FLOW THRU 06/12Z
WITH SOME POTENTIAL OF HIGHER GUSTS NEAR TSTMS.
PREV DISCUSSION... /ISSUED 328 AM CDT FRI JUL 5 2013/
STRONG BERMUDA HIGH CENTERED OVER THE WESTERN ATLANTIC WITH AN
UNUSUALLY STRONG MID SUMMER TROUGH OVER THE NATIONS INTERIOR. DEEP
SOUTHERLY FLOW EXISTS BETWEEN THE TWO FEATURES. AT THE SFC...A
WEAKENING N-S STATIONARY FRONTAL BOUNDARY STRETCHES FROM THE WESTERN
GULF NE THROUGH MS AND WESTERN TN.
CURRENTLY...A BRIEF LULL IN THE WET PATTERN IS INDICATED. 850 MB
FLOW IS SLIGHTLY ENHANCED BUT THE DEGREE OF SPEED CONVERGENCE IS
OVERDONE. UPPER TROUGH APPEARS TO BE TOO FAR WEST TO EXPAND ON ANY
UPPER DIVERGENCE ACROSS THE AREA. THUS...THE KEY CATALYST WOULD
NEED TO BE DISTURBANCES WITHIN THE MID/UPPER LEVEL SOUTHERLY FLOW.
LATEST MODELS SUGGEST THE BETTER DISTURBANCES HAVE SHIFTED NORTH
FOR NOW.
FOR TODAY...AIRMASS WILL NEED A LITTLE DAYTIME HEATING TO GET THE
CONVECTION GOING. BUT BY AFTERNOON AND TONIGHT...THE AFOREMENTIONED
UPPER TROUGH WILL BEGIN MOVING EASTWARD WHILE THE ASSOCIATED UPPER
LOW MOVE SOUTHEASTWARD. THIS WILL ALLOW DEEPER MOISTURE TO RETURN
WITH ADDITIONAL DYNAMICS COMING INTO PLAY. THUS...THE LIKELY TO
CATEGORICAL POPS WILL RETURN THIS AFTERNOON AND INTO TONIGHT.
NOW...AS FAR AS THE FLASH FLOOD WATCH GOES...RAINFALL AMOUNTS HAVE
BEEN GENERALLY IN THE 1-2 INCH RANGE SO FAR BUT SCATTERED AREAS
HAVE RECEIVED MUCH MORE. LATEST FFG SUGGEST THAT ONLY AN INCH OR SO
OF RAINFALL IN THE 1-3 HR PERIOD MAY CAUSE FLASH FLOODING.
THUS...WILL ELECT TO KEEP THE FLASH FLOOD WATCH GOING. IT DOES
EXPIRE FRIDAY EVENING(THIS UPCOMING EVENING). WILL ALLOW THE DAY
SHIFT TO DECIDE ON WHETHER OR NOT TO EXTEND THE WATCH.
OTHERWISE...THUS FAR...THE MODELS HAVE TENDED TO BE A LITTLE TOO
AGGRESSIVE WITH THE QPF FROM THIS SYSTEM. THUS...WILL LEAN TOWARD
THE HPC QPF ESTIMATIONS FOR THE QPF GRIDS.
AS WE GO FORWARD IN TIME...THE UPPER TROUGH WILL BE MOVING EASTWARD
WITH THE AXIS CROSSING THE MID STATE ON SUNDAY. IT WILL BE AT THIS
POINT THAT OUR POPS WILL BEGIN TO DECREASE...SETTING THE STAGE FOR A
MORE SUMMER-LIKE PATTERN FOR THE EXTENDED PERIOD.
FOR THE NEAR TERM TEMPS...WITH THE INFLUENCES OF THE UPPER
TROUGH...CLOUDS AND PRECIPITATION...BELOW NORMAL TEMPS WILL CONTINUE
THROUGH SUNDAY. VERSUS THE MAV GUIDANCE...A SLIGHT UNDERCUT OF MAX
VALUES WILL BE INCLUDED.
IN THE EXT FCST...ONCE THE UPPER TROUGH AXIS MOVES EAST...WE WILL
REVERT MORE TOWARD A TYPICAL SUMMERTIME PATTERN. THE BERMUDA HIGH
AND THE UPPER HIGH OVER THE SOUTHERN PLAINS WILL BOTH WEAKEN. THE
WEAKNESS WITHIN THE TWO UPPER LEVEL HIGHS WILL STILL ALLOW
CONVECTION POSSIBILITIES TO CONTINUE...BUT AREAL COVERAGE WILL BE
MUCH LESS THAN WHAT WE ARE SEEING THROUGH MUCH OF THE NEAR TERM
FORECAST.
AS WE MOVE TOWARD THE END OF THE EXT PERIOD...WEAK TROUGHING/NW FLOW
WILL RETURN WITH POPS AND QPF AMOUNTS INCHING UPWARD ONCE AGAIN.
FOR THE EXT TEMPS...VALUES WILL LOOK VERY SEASONAL AS A WEAK W-E
RIDGE PREVAILS AND 850 MB TEMPS RANGE FROM 18C-20C. VERSUS THE
MEX...WILL INCLUDE A SLIGHT UNDERCUT.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR TNZ007>011-026>034-
059>066-075-077>080-094-095.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1146 AM CDT FRI JUL 5 2013
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
CLOUD COVER LESS EXTENSIVE THAN YESTERDAY BUT IS BEGINNING TO
INCREASE OVER THE SW ZONES. LEANED TOWARD THE RAP WHICH SHOWS SOME
SHRA/TSRA DEVELOPING ALONG THE SEA BREEZE OVER THE SW ZONES. ADDED
VCSH FOR KLBX FOR THIS AFTN BUT OTHERWISE KEPT PCPN OUT OF THE
TAFS. EXPECTING THE SEA BREEZE TO MOVE INLAND SO INCREASED WIND
SPEEDS FOR LATER THIS AFTN. MORE OF AN EAST WIND EXPECTED ON
SATURDAY. 43
&&
.PREV DISCUSSION... /ISSUED 1043 AM CDT FRI JUL 5 2013/
UPDATE...
ANTICIPATING A SIMILAR DAY TO YESTERDAY...PARTIALLY CLOUDY SKIES
WITH MAXIMUM TEMPERATURES ACHIEVING THE AVERAGE MIDDLE 90S.
SLIGHTLY HIGHER MOISTURE VALUES WITH THE BEST THERMODYNAMICS AND
FAVORABLE BULK SHEAR HUGGING THE COASTLINE AND POINTS OFFSHORE.
MODERATE CONFIDENCE THAT EARLY AFTERNOON CONVECTION (PRIMARILY
EARLY DAY SHOWERS) WILL FOCUS ON THE SLOWLY INLAND-ADVANCING SEA
BREEZE BOUNDARY. ONCE SURFACE TEMPERATURES REACH THE LOWER 90S
THERE WILL BE MORE AREAWIDE SHOWERS WITH EMBEDDED STORMS AFFECTING
FURTHER INLAND COMMUNITIES. 31
PREV DISCUSSION... /ISSUED 445 AM CDT FRI JUL 5 2013/
DISCUSSION...
SFC ANALYSIS HAS WEAK PRESSURE GRADIENT OVER SE TX SO WINDS ARE
CALM WITH SOME LIGHT SE WINDS OFFSHORE. LOW LEVEL MOISTURE HAS
INCREASED SO SEEING TEMPS DROP CLOSER TO DEWPOINT TEMPS THIS
MORNING RESULTING IN PATCHY FOG MAINLY IN RURAL AREAS. WATER VAPOR
AND UPPER AIR ANALYSIS HAS UPPER LOW OVER UPPER MISS RIVER VALLEY
AND ITS TROUGH AXIS STRETCHING DOWN INTO SE TX. THIS MAY SUPPORT A
FEW STORMS THIS AFTERNOON BUT THINK SEA BREEZE MAY BE THE MAIN
TRIGGER FOR CONVECTION. MOISTURE LEVELS ARE INCREASING BUT STILL
BORDERLINE FOR WIDESPREAD ACTIVITY. THINK 20 POPS LOOK ON TRACK
FOR TODAY WITH ISOLATED ACTIVITY. THAT SAID FORECAST SOUNDINGS
SUGGEST 1000-1500 J/KG CAPE AND SOME DRY AIR WHICH WILL SUPPORT
STRONGER DOWNDRAFTS. COULD SEE A SEVERE DOWNBURTS OCCUR WITH ANY
OF THESE COLLAPSING STORMS.
UPPER LOW SHOULD THEN TRACK EAST INTO THE MIDWEST FOR SATURDAY
WITH STILL AN OVERALL WEAKNESS IN THE UPPER FLOW STRETCHING
TOWARDS THE NW GULF. ATMOSPHERIC MOISTURE RIVER SHOULD SHIFT WEST
DURING THIS TIME SO THINK DEEPER TROPICAL MOISTURE WILL MOVE INTO
THE AREA STARTING SATURDAY. FOR NOW 20/30 POPS LOOK GOOD WITH
HIGHER CHANCES ALONG THE COAST.
FORECAST GETS A BIT MORE CHALLENGING FOR SUN/MON TIME FRAME.
MODELS STILL HINT AT A TROPICAL WAVE OR EVEN A WEAK DEPRESSION
FORMING IN THE W GULF SATURDAY INTO SUNDAY. MODELS MORE AND MORE
CONSISTENT WITH BRINGING THE TROPICAL DISTURBANCE TO THE UPPER TX
COAST BY 12Z SUNDAY. SO HAVE INCREASED RAIN CHANCES TO 50/60
PERCENT ALONG THE COAST AS THIS DISTURBANCE MOVES INLAND ALONG THE
COAST. GFS/NAM BRING PRECIP WATER VALUES IN EXCESS OF 2.3 INCHES
WHICH WOULD BE ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL FOR EARLY
JULY OR CLOSE TO THE 99TH PERCENTILE. THIS SUGGESTS A THREAT FOR
HEAVY RAINFALL AND DECIDED TO MENTION IN THE FORECAST. THINK HEAVY
RAINFALL THREAT WILL BEGIN 12Z SUN AND GO THROUGH 12Z MON. SHOULD
THIS MATERIALIZE THINK ANY FLOODING THREAT WILL BE MORE IN URBAN
AREAS WITH POOR DRAINAGE AS GROUNDS ARE STILL VERY DRY AND CAN
HOLD QUITE A BIT OF RUNOFF. RAINFALL AMOUNTS WILL BE TOUGH TO
DETERMINE BUT THINK 1 TO 3 INCHES OF RAIN WILL BE POSSIBLE ALONG
THE COAST. GIVEN THAT MUCH TROPICAL MOISTURE...COULD SEE A FEW
ISOLATED AREAS OF 5 INCHES ESPECIALLY IF STORMS TRAIN OVER THE
SAME AREA. THEN THERE IS THE QUESTION OF TROPICAL DEVELOPMENT.
STILL NEED TO MONITOR FOR TROPICAL DEVELOPMENT BUT WIND SHEAR
LOOKS TOO STRONG AT THIS TIME. UPPER LEVEL WINDS REALLY DO NOT
DECREASE MUCH INTO SUN MORNING SO IT WILL BE DIFFICULT FOR A
TROPICAL SYSTEM TO FORM. THE NAM STILL WANTS TO CLOSE OFF A
CIRCULATION BUT GFS/ECMWF KEEP IT AS AN OPEN TROPICAL WAVE. AT
THIS TIME THINK A TROPICAL WAVE IS MOST LIKELY GIVEN THE
ENVIRONMENT.
DEEPER TROPICAL MOISTURE WILL REMAIN OVER THE AREA MONDAY INTO
TUESDAY SO HELD ONTO 40/50 POPS FOR MONDAY AND 30 POPS FOR
TUESDAY. UPPER LEVEL RIDGING TRIES TO TAKE HOLD OVER THE PLAINS
FOR THE MIDDLE OF NEXT WEEK BUT NEVER REALLY BECOMES ESTABLISHED.
A TUTT LOW WAY OUT IN THE ATLANTIC UNDERCUTS THE BERMUDA RIDGE
AND WORKS INTO FLORIDA TUE/WED TIME FRAME. THIS WILL HELP KEEP
LOWER HEIGHTS OVER THE AREA FOR THE END OF NEXT WEEK. WILL CARRY
20 POPS FOR MAINLY AFTERNOON STORMS ON THE SEA BREEZE BUT
POSSIBLE THERE MAY BE MORE COVERAGE THAN JUST ISOLATED STORMS.
39
MARINE...
EAST SOUTHEASTERLY WINDS WILL BE ON THE INCREASE TODAY AS
A WEAK TROUGH OF LOW PRESSURE DEVELOPS ACROSS THE SOUTHERN GULF OF
MEXICO BEFORE DRIFTING TOWARDS THE TEXAS COAST. WINDS WILL BECOME
MORE SOUTHERLY ON SUNDAY AS THE TROUGH MOVES INLAND WITH WINDSPEEDS
INCREASING ACROSS THE UPPER TEXAS COASTAL WATERS SATURDAY NIGHT INTO
SUNDAY.
ALTHOUGH WIND SHEAR REMAINS RATHER STRONG ACROSS THE GULF THE NAM
MODEL RUNS CONTINUE TO SHOW A WEAK TROPICAL SYSTEM DEVELOPING AND
MOVING TOWARDS THE TEXAS COAST. IF THIS SCENARIO WERE TO DEVELOP WE
WOULD SEE STRONGER WINDS AND MUCH HIGHER SEAS OVER THE WEEKEND.
COASTAL RESIDENTS AND PERSONS WITH MARINE INTERESTS ARE URGED TO
CONTINUE MONITORING THE LATEST WEATHER FORECASTS FOR UPDATED
INFORMATION. HAVE INCREASED SEAS FOR SUNDAY AS STRONGER WINDS WILL
DRIVE THEM UP SLIGHTLY WHETHER A CLOSED LOW SYSTEM DEVELOPS OR NOW.
TIDE LEVELS ARE CURRENTLY RUNNING ABOUT A FOOT ABOVE NORMAL AND A
FURTHER INCREASE IN TIDE LEVELS WILL BE POSSIBLE OVER THE WEEKEND AS
EAST WINDS INCREASE. BEACHGOERS SHOULD ALSO STAY ALERT FOR RIP
CURRENTS OVER THE WEEKEND AS INCREASING EAST WINDS AND BUILDING SEAS
WILL CREATE A FAVORABLE ENVIRONMENT FOR RIP CURRENTS TO DEVELOP. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 72 96 75 91 / 20 10 10 10 20
HOUSTON (IAH) 96 73 94 77 89 / 20 10 20 30 50
GALVESTON (GLS) 92 78 90 80 87 / 20 20 30 50 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...31
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1127 PM CDT THU JUL 4 2013
.AVIATION...
SOUTHEAST WINDS WILL CONTINUE TO SLOWLY DECREASE...BUT ARE
EXPECTED TO REMAIN AROUND 10KT OVERNIGHT THROUGH FRIDAY.
THE UPPER TROUGH AXIS WILL SHIFT EAST OVER THE NEXT 24 HOURS
WHICH SHOULD BRING EVEN LESS OF A CHANCE FOR CONVECTIVE WEATHER
FRIDAY THAN WHAT TRANSPIRED THIS AFTERNOON AND EVENING. THE
RESULTING TAFS WILL REMAIN SIMPLE AND QUIET WITH VFR CONDITIONS
EXPECTED THROUGH THE DURATION OF THIS FORECAST CYCLE.
30
&&
.UPDATE...
ALL SHOWERS AND STORMS HAVE DISSIPATED WITH THE LOSS OF SURFACE
HEATING. WILL SEND OUT A QUICK UPDATE TO REMOVE FIRST PERIOD POPS
AND ADJUST HOURLY GRIDS. NO OTHER CHANGES AT THIS TIME.
79
&&
.PREV DISCUSSION... /ISSUED 352 PM CDT THU JUL 4 2013/
SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE THIS AFTERNOON ACROSS
MAINLY THE FAR EASTERN COUNTIES IN A MODERATELY UNSTABLE AND
UNCAPPED ENVIRONMENT WITH WEAK DEEP LAYER SHEAR. THE SLOW MOVING
SHOWERS AND THUNDERSTORMS ARE PRODUCING SOME GUSTY WINDS AND
LOCALLY HEAVY RAINFALL. THIS TREND WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON AS WEAK FORCING FROM THE LARGE UPPER
TROUGH WILL CONTINUE TO SUPPORT UPWARD VERTICAL MOTIONS.
ADDITIONAL STORMS ARE ALSO LIKELY TO DEVELOP ALONG THE REMNANT
OUTFLOWS OF DYING THUNDERSTORMS. ALL OF THIS ACTIVITY SHOULD TAPER
OFF LATER THIS EVENING AS THE SUN GOES DOWN. ENVIRONMENT ACROSS
THE EAST STILL REMAINS SOMEWHAT FAVORABLE FOR STRONG DOWNBURST
WIND GUSTS WITH THE STRONGEST OF STORMS AND FREQUENT CLOUD TO
GROUND LIGHTNING WILL ALSO BE A THREAT THROUGH EVENING.
FARTHER WEST...A FEW LIGHT ECHOES ARE NOTED ON RADAR NEAR
COMANCHE. THE AIR IS MUCH DRIER HERE AT THE SURFACE SO THIS
ACTIVITY IS BASED MUCH HIGHER. MODIFIED RAP SOUNDINGS SHOW LCL/S
AROUND 12000FT WITH ABOUT 500J/KG OF SURFACE BASED CAPE. THIS
ACTIVITY SHOULD BE SHORT LIVED BUT COULD PRODUCE SOME GUSTY WINDS.
FOR THIS EVENING...WILL KEEP 20 POPS GOING ACROSS THE EASTERN
COUNTIES THROUGH ABOUT 9 PM. OTHERWISE...MOST AREAS WILL SEE
PARTLY CLOUDY SKIES WITH TEMPERATURES FALLING INTO THE 80S AFTER
DARK FOR FIREWORKS.
ON FRIDAY THE MAIN UPPER TROUGH OVER THE CENTRAL US BEGINS TO
SHIFT A LITTLE FARTHER EAST AND RIDGING TO THE WEST WILL BEGIN TO
BUILD INTO OUR AREA. THIS SHOULD MEAN LESS COVERAGE OF SHOWERS AND
THUNDERSTORMS TOMORROW AFTERNOON ACROSS THE AREA WITH SLIGHTLY
WARMER TEMPERATURES.
THE NEXT FEATURE OF CONCERN MOVES IN FOR THE LATTER PART OF THE
WEEKEND INTO EARLY NEXT WEEK. AN UPPER LOW OVER THE GULF WILL MOVE
INLAND ALONG THE TEXAS COAST LATE SUNDAY. THERE IS A LARGE
RESERVOIR OF 2 INCH PLUS PWS OVER MUCH OF THE CENTRAL AND EASTERN
GULF THIS AFTERNOON. THIS WILL BEGIN TO MOVE WESTWARD WITH THE
UPPER LOW BY THE END OF THE WEEKEND. THERE ARE SOME SUBSTANTIAL
DIFFERENCES BETWEEN THE GUIDANCE AS TO THE HANDLING OF THE UPPER
LOW. THE GFS IS MUCH SLOWER AND WEAKER WITH THE UPPER RIDGE AND
THEREFORE HAS MORE CLOUDS AND RAIN FOR EARLY NEXT WEEK ACROSS
NORTH TEXAS. THE ECMWF MOVES THE GULF LOW INLAND VERY QUICKLY AND
KEEPS A STRONGER RIDGE. FOR THIS FORECAST...WILL LEAN CLOSER TO
THE GFS SOLUTION AS THESE TYPES OF UPPER LOWS ARE GENERALLY SLOWER
MOVING WHEN ASSOCIATED WITH LARGE POOLS OF RICH GULF MOISTURE.
GENERALLY LARGE CLUSTERS OF SHOWERS AND THUNDERSTORMS NEAR THE
COAST OR INLAND CAN OFTEN TIMES HELP RELOCATE THE CENTER OF THE
MID LEVEL LOW IN WEAK FLOW ENVIRONMENTS. IF THIS HAPPENS...ITS
MOVEMENT WOULD APPEAR CONSIDERABLY SLOWER THAN ADVERTISED BY THE
ECMWF. RAIN CHANCES LOOK BEST ACROSS THE CENTRAL AND SOUTHEAST
PART OF THE STATE...BUT ANYTIME WE GET A WEAK UPPER LOW AND
MOISTURE TO WORK WITH...SCATTERED SHOWERS AND STORMS ARE A
POSSIBILITY. BEST CHANCES FOR NORTH TEXAS APPEAR TO BE MONDAY AND
TUESDAY.
TEMPERATURES WILL SLOWLY WARM THROUGH THE WEEKEND AND HUMIDITY
WILL GO UP WITH TIME MAKING IT FEEL MORE LIKE SUMMER. WILL HAVE TO
MONITOR THE PROGRESSION OF THE UPPER LOW NEXT WEEK TO ASSESS ITS
IMPACTS ON TEMPS/RAIN CHANCES.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 72 96 73 96 74 / 10 5 5 5 5
WACO, TX 70 97 71 98 73 / 10 5 5 5 5
PARIS, TX 66 92 67 93 71 / 10 10 5 5 5
DENTON, TX 69 93 70 94 72 / 10 5 5 5 5
MCKINNEY, TX 67 94 70 95 72 / 10 5 5 5 5
DALLAS, TX 75 97 76 97 77 / 10 5 5 5 5
TERRELL, TX 69 95 71 96 73 / 10 5 5 5 5
CORSICANA, TX 71 96 73 97 73 / 10 5 5 5 5
TEMPLE, TX 68 97 70 97 73 / 10 5 5 5 5
MINERAL WELLS, TX 69 96 71 96 72 / 10 5 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/79
AREA FORECAST DISCUSSION
NWS SPOKANE WA
432 PM PDT Sat Jul 6 2013
.SYNOPSIS...
Mainly clear skies and light winds are expected through Monday.
There will be a chance for thunderstorms over the North Cascades
this evening and once again on Sunday. Tuesday should be the
warmest day of the week with high temperatures in the upper 80s to
mid 90s. Wednesday will be locally breezy with the arrival of a
cold front. The front will knock temperatures back close to normal
for Thursday, Friday, and Saturday.
&&
.DISCUSSION...
Tonight: Isolated thunderstorms have been retained in the forecast
for this evening over the north Washington Cascades and for the
high terrain near Bonners Ferry...Clark Fork...and Priest Lake.
Showers have been slow to develop this afternoon. As of 2 PM, a
couple of weak cells were evident over far north Idaho, but
nothing resembling deep convection. The RUC surface based CAPE
analysis depicts more instability over the Cascade crest from
Snoqualmie Pass north into southern B.C. The NAM, GFS, SREF and
HRRR all produce at least a little convective precipitation over
the Cascades between 3 PM and 8 PM, so a 20 percent chance of
terrain based thunderstorms has been retained through early this
evening. For the remainder of north Idaho and east Washington,
mainly light winds and mostly clear skies will be the rule for
tonight. Great weather for the 4th of July weekend.
Sunday: Our main area of interest for Sunday will once again be
the north Washington Cascades. A more dynamic upper low (currently
off the coast of central B.C.) will dig over northwest Washington
on Sunday afternoon. Look for thunderstorms to initiate by early
to mid afternoon on Sunday from Stevens Pass and points north.
Instability and shear parameters resemble what we saw yesterday
over the Okanogan Highlands, so locally heavy rain, small hail,
and gusty winds will be possible. The mention of thunderstorms has
been added to the Hazardous Weather Outlook. The East Slopes of
the Cascades is a potentially high impact area. The 25-Mile
Wildfire on the north shore of Lake Chelan is susceptible to
erratic thunderstorm outflow. The 2012 burn scars around Wenatchee
and Chelan are also prone to mud slides and flash flooding. At
this time, the model consensus is for the most concentrated
thunderstorm activity to be north of Lake Chelan. The thunderstorm
threat will certainly be worth monitoring Sunday and Sunday
evening. East of the Cascades, the weather looks much more benign.
Mainly sunny skies and light winds are expected once again on
Sunday. /GKoch
Sunday night, Monday and Monday night: There will be a chance of
showers and thunderstorms across the northern mountains as an
upper level trough axis swings across the Inland NW. After the
diurnally driven convection wanes Sunday evening, upper level
dynamics will take over and keep the threat of showers with
embedded thunderstorms going from the far northern Cascades,
across the Okanogan Highlands and into the Northeast Mountains and
far north Idaho late Sunday night and into Monday morning. There
is also a smaller possibility of convection across the Blue
mountains and into the central ID panhandle where a wedge of mid
level instability develops. Meanwhile winds will be gusty in the
Cascade valleys Sunday night and spilling into the Columbia Basin.
The upper level disturbance will exit by Monday afternoon although
lingering low level instability will keep the mention of afternoon
and evening convection across northeast Washington and north
Idaho. Drier westerly flow will move into the region Monday night
as high pressure moves into the region. Temperatures will be
running slightly above normal. /rfox.
Tuesday through Thursday: A ridge of high pressure shifts east
and opens the door for the passage of two or three systems. The
main result looks to be, after peak heating on Tuesday, a slight
cool-down and locally breezy afternoon and/or evening conditions.
All models show lower afternoon relative humidity, especially
Wednesday. The critical winds may not sync with the lowest
humidity. Yet this will be monitored for possible impacts for fire
weather concerns. The passing systems suggest possible shower
chances. A weak impulse slips by the northern Cascades and
Canadian border Tuesday as the ridge axis is shifting east. While
models are not in total agreement on its timing, more than half
indicate some afternoon CAPE in the above locations. So I kept a
slight chance of showers and thunderstorms going here.
A second, deeper shortwave passes Wednesday afternoon into
Thursday morning and a third wave comes up from the southwest
Thursday afternoon. First during the day Wednesday the deeper wave
drops down the BC coast toward WA, while a jet streak comes up
through northern CA and OR. The BC shortwave pivots inland
sometime between late Wednesday afternoon and Wednesday night. The
deepest lift appears to remain north of the Canadian border. Yet a
cold front crossing eastern Washington into northern Idaho late
Wednesday into Thursday morning and jet streak coming up from
southwest will provide some lift. The third shortwave rides up
along the stalled front. Slower models bring this wave by
southeast Washington and northern Idaho; other keep it across
Oregon and central and southern Idaho.
The question is: will there be enough instability and/or moisture
when these features come through to generate any precipitation?
The continued disagreements in timing lessen forecaster
confidence. I kept shower and thunderstorms chance going across
the northern mountains, as well as near the Blues through central
Panhandle. But the overall best instability remains around but not
over eastern WA and northern ID, so the precipitation chances
remain low. /J. Cote`
Thursday Night through Saturday: Pattern for this period looks
rather active compared to what we have seen in the recent past.
Models are in decent agreement given this being quite a ways out.
Late Friday into Saturday will see a system pushing in from the NW
bringing some moisture with it. By the end of this time frame we
will have the upper level low continue to push to the east and
out of our area diminishing the threat for showers.
Examining the threat for showers we will see the system track
along the USA/BC border and increase the chances for showers in
these areas but overall the best chances look to be in NE WA and
the N Idaho Panhandle as that is where the models put the majority
of the QPF. Increased chances for showers and thunderstorms will be
present throughout the day on Saturday. Currently the mention of
showers is for the higher elevations as topography will likely play
a key role initiating the showers. The Euro brought the system to
the south much further than the previous run following what the
GFS had been showing. This brings higher confidence of the
event...the question will be whether t-storms are present or if it
is simply showers. Total totals would be supportive along with
shear and the upper level cold pool with the system...but very
limited CAPE and positive LIs would hinder storm development.
This will be something we watch in the upcoming days to see how
models bring this system in.
The other thing to keep an eye on will be the winds as they will
pick up with the passing of the system due to the tightened gradient.
Currently only breezy conditions are in the forecast...but if the
track of the system would change this could lead to increased
winds. As we progress closer to the event model agreement will
hopefully increase allowing for more confidence in this weekend
system. /Fliehman
&&
.AVIATION...
00Z TAFS: Light winds and mainly clear skies tonight for eastern
Washington and north Idaho. More of the same for Sunday with the
exception of scattered showers and thunderstorms over the Cascades
north and west of Wenatchee. The chance that storms tomorrow reach
the Wenatchee or Chelan areas is very low. /GKoch
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 56 85 58 84 58 88 / 0 0 0 10 0 0
Coeur d`Alene 53 84 55 82 53 86 / 0 0 0 10 10 0
Pullman 46 83 51 83 49 87 / 0 0 10 10 0 0
Lewiston 57 92 61 91 60 95 / 0 0 10 10 0 0
Colville 50 88 53 87 53 91 / 10 10 20 20 10 10
Sandpoint 47 83 51 81 50 85 / 10 0 10 30 20 10
Kellogg 52 83 54 82 54 85 / 10 0 0 20 10 0
Moses Lake 56 91 59 91 58 94 / 0 0 10 0 0 0
Wenatchee 61 89 61 89 63 92 / 0 10 10 0 0 0
Omak 56 89 56 90 58 93 / 0 10 20 10 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1101 PM CDT SAT JUL 6 2013
.UPDATE...
ISSUED AT 627 PM CDT SAT JUL 6 2013
DID A QUICK ADJUSTMENT TO THE FORECAST TO DELAY ANY PRECIPITATION
CHANCES UNTIL AFTER 06Z. 06.18Z NAM...06.12Z
ECMWF/CANADIAN...06.20/21Z HRRR AND 06.21Z/22Z RAP ALL KEEP ANY
ISENTROPICALLY INDUCED SHOWERS TO THE NORTH AND WEST OF THE
FORECAST AREA THROUGH 06Z. IN FACT...THE HRRR...RAP AND 06.12Z SPC
WRF-NMM SUGGEST THE FORECAST AREA MINUS TAYLOR/CLARK COUNTIES COULD
END UP DRY THROUGH SUNDAY MORNING. THIS WOULD MAKE SENSE TOO LOOKING
AT THE 06.18Z NAM 310-315K ISENTROPIC LIFT FIELDS. THESE FIELDS
SHOW LIFT...WHICH IS CURRENTLY HELPING TO PRODUCE THE ALTOSTRATUS
AND SOME SHOWER ACTIVITY BACK IN SOUTHWEST TO CENTRAL
MN...WEAKENING AS IT APPROACHES AND MOVES THROUGH THE AREA DURING
THE 9-18Z TIME PERIOD. IF MODEL TRENDS CONTINUE...MAY END UP
LOWERING PRECIPITATION CHANCES OR COMPLETELY DRYING OUT SOME OF
THE FORECAST BETWEEN 06-18Z.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 334 PM CDT SAT JUL 6 2013
LATEST WATER VAPOR IMAGERY SHOWED A CUTOFF LOW OVER THE MIDDLE
MISSISSIPPI RIVER VALLEY. TWO AREAS OF HIGH PRESSURE NOTED...ONE OFF
OF THE EAST COAST AND ANOTHER ANCHORED OVER NORTH CENTRAL MEXICO.
FLOW WAS TRANSITIONING TO ZONAL OVER THE PACIFIC NORTHWEST THROUGH
THE NORTHERN PLAINS. A SHORTWAVE WAS MOVING ACROSS NORTH DAKOTA
WITH ANOTHER WAVE NOTED OVER NORTHERN MINNESOTA. ANOTHER..WEAKER
WAVE WAS NOTED MOVING EAST ACROSS SOUTH DAKOTA. SURFACE
OBSERVATIONS SHOWED A WEAK FRONTAL BOUNDARY EXTENDING FROM CENTRAL
NORTH DAKOTA EAST THROUGH NORTHERN MINNESOTA.
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ACROSS EASTERN SOUTH
DAKOTA INTO CENTRAL AND PORTIONS OF NORTHERN MINNESOTA THIS
AFTERNOON. THIS ACTIVITY IS EXPECTED TO BECOME MORE WIDESPREAD THIS
EVENING AS 850 MB MOISTURE TRANSPORT INCREASES AND FOCUSES INTO
CENTRAL AND NORTHERN MINNESOTA. THE BULK OF THE ACTIVITY WILL BE
NORTHWEST OF THE FORECAST AREA INTO THE LATE EVENING HOURS. THE
MOISTURE TRANSPORT THEN ATTEMPTS TO SHIFT EAST EARLY SUNDAY MORNING
AS THE WEAK SHORTWAVE PUSHES EAST INTO THE UPPER MISSISSIPPI RIVER
VALLEY. INSTABILITY AND UPPER LEVEL FORCING IS REALLY WANING AS THE
MOISTURE TRANSPORT MOVES IN. THE WAVE DOES MAKE ITS WAY THROUGH THE
AREA SUNDAY MORNING WITH SCATTERED SHOWERS AND PERHAPS AN ISOLATED
THUNDERSTORM POSSIBLE. THE FRONTAL BOUNDARY SLIDES SOUTHEAST DURING
THE DAY ON SUNDAY AND BY LATE AFTERNOON IS EXPECTED TO STRETCH FROM
WEST CENTRAL IOWA NORTHEAST THROUGH NORTHWEST WISCONSIN. 0-3KM MUCAPE
CLIMBS TO AROUND 3000 J/KG AHEAD OF THE FRONT. HOWEVER...UPPER LEVEL
RIDGING IS OCCURRING DURING THIS TIME FRAME AND SHOULD ACT TO
SUPPRESS CONVECTION AT LEAST UNTIL LATE AFTERNOON WHEN A VERY WEAK
SHORTWAVE MOVES IN. THE FRONT PROGRESSES SOUTHEAST THROUGH THE
EVENING HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT
BUT THINKING THEY WILL STRUGGLE TO DEVELOP WITH THE RIDGING
OCCURRING ALOFT. IF STORMS CAN OVERCOME THE RIDGING...CANNOT RULE
OUT AN ISOLATED SEVERE STORM OR TWO WITH LARGE HAIL AND DAMAGING
WINDS. HAVE MAINTAINED LOW THUNDERSTORM CHANCES THROUGH THE
AFTERNOON. PLAN ON HIGHS ON SUNDAY RANGING FROM THE LOWER 80S OVER
NORTH CENTRAL WISCONSIN TO THE UPPER 80S OVER PORTIONS OF
NORTHEAST IOWA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 334 PM CDT SAT JUL 6 2013
THE FRONT SLIDES SOUTH INTO NORTHERN IOWA AND NORTHERN ILLINOIS
SUNDAY NIGHT INTO MONDAY MORNING WITH THE HIGHER CHANCES FOR
SHOWERS AND STORMS FOCUSED ALONG THE FRONT LATE SUNDAY NIGHT. FLOW
ALOFT THEN FINALLY TURNS ZONAL ON MONDAY WITH EMBEDDED SHORTWAVES
INTERACTING WITH THE FRONT AS IT STARTS TO ACT AS A WARM FRONT.
PRECIPITABLE WATER VALUES HOVER AROUND 170 PERCENT OF NORMAL OVER
NORTHERN IOWA THROUGH SOUTHERN WISCONSIN LATE MONDAY AFTERNOON
THROUGH TUESDAY MORNING. 850 MB MOISTURE TRANSPORT FOCUSES INTO
THE THE FRONT MONDAY NIGHT INTO TUESDAY MORNING AND COLD LEAD TO
REPEATED ROUNDS OF SHOWERS AND STORM ALONG IT. WITH WARM CLOUD
DEPTHS IN THE 4000 TO 4200 METER RANGE...THE STORMS WILL BE
EFFICIENT RAIN PRODUCERS. WILL HAVE TO KEEP A VERY CLOSE EYE ON
THE POTENTIAL FOR HEAVY RAINFALL ALONG THIS FRONT. THERE ARE
SIGNALS SUGGESTING THE FRONT COULD STALL OVER NORTHEAST IOWA AND
SOUTHWEST WISCONSIN...LEADING THE POTENTIAL FOR FLASH FLOODING
FROM REPEATED ROUNDS OF STORMS MONDAY NIGHT INTO TUESDAY MORNING.
THE 18Z NAM IS A BIT FURTHER SOUTH PLACING THE WARM FRONT OVER
SOUTHERN IOWA WHICH WOULD PLACE THE THREAT FOR HEAVY RAIN CLOSER
TO THE INTERSTATE 80 CORRIDOR.
A SHORTWAVE TROUGH APPROACHES THE REGION FROM THE NORTHERN PLAINS
TUESDAY AFTERNOON. A COLD FRONT WILL PUSH SOUTH ACROSS THE NORTHERN
PLAINS AND INTO THE UPPER MISSISSIPPI RIVER VALLEY TUESDAY AFTERNOON
INTO TUESDAY EVENING. 0-3KM MUCAPE VALUES CLIMB INTO THE 1500 TO
2500 J/KG RANGE TUESDAY AFTERNOON AHEAD OF THE FRONT WHILE 0-6 KM
BULK SHEAR INCREASES TO AROUND 30 KTS. DEPENDING ON HOW LONG THE
MORNING CONVECTION HOLDS ON...SEVERE THUNDERSTORMS ARE A POSSIBILITY
TUESDAY AFTERNOON INTO TUESDAY EVENING. LARGE HAIL...DAMAGING WINDS
AND HEAVY RAINFALL WOULD BE THE MAIN HAZARDS. THE COLD FRONT THEN
SWEEPS SOUTH ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY MORNING AS
SURFACE HIGH PRESSURE BUILDS IN. QUIET WEATHER AND SEASONABLE
TEMPERATURES ARE EXPECTED IN THE WAKE OF THE FRONT FROM WEDNESDAY
AFTERNOON THROUGH FRIDAY WITH HIGHS IN THE 80S AND LOWS MAINLY IN
THE 60S. AN UPPER RIDGE BUILDS OVER THE REGION BRIEFLY LATE IN THE
WEEK...BUT THEN LOOKS TO BREAK DOWN LATE FRIDAY INTO SATURDAY AS A
SHORTWAVE MOVES ACROSS THE DAKOTAS AND INTO THE UPPER MISSISSIPPI
RIVER VALLEY BRINGING CHANCES FOR SHOWERS AND STORMS TO THE
AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1101 PM CDT SAT JUL 6 2013
CONFIDENCE REMAINS VERY LOW ON ANY PRECIPITATION AFFECTING THE TAF
SITES THROUGH SUNDAY EVENING. A COUPLE OF ISSUES EXIST...INCLUDING
DRY AIR FROM NEAR THE GROUND UP TO 8000 FT OR SO...MODEL HANDLING
THUS FAR WHICH HAS GENERALLY SHOWN TOO MUCH SHOWER AND
THUNDERSTORM ACTIVITY ALONG/SOUTH OF I-94 ACROSS THE UPPER
MIDWEST...AND SOME EVIDENCE RECENTLY OF ALTOSTRATUS FROM CENTRAL
MINNESOTA INTO WESTERN IOWA DISSIPATING. MODELS CONTINUE TO TREND
DRIER FOR THE MORNING HOURS...THOUGH. THERE MAY BE A WEAKENING
COLD FRONT APPROACHING THE TAF SITES LATE THIS AFTERNOON INTO THIS
EVENING FROM CENTRAL MN...HOWEVER...WARM AIR MOVING IN ALOFT OVER
THE FRONT MAY CAP ANY SHOWERS OR STORMS THAT TRY TO FORM.
THUS...THE 06Z TAFS DO NOT SHOW ANY PRECIPITATION WITH VFR
CONDITIONS CONTINUING. SOUTH TO SOUTHWEST WINDS LOOK TO
PERSIST...GENERALLY 12 KT OR LESS...WITH A WEAKER PRESSURE
GRADIENT FORECAST PROMOTING LIGHTER WINDS COMPARED TO THE PAST FEW
DAYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
627 PM CDT SAT JUL 6 2013
.UPDATE...
ISSUED AT 627 PM CDT SAT JUL 6 2013
DID A QUICK ADJUSTMENT TO THE FORECAST TO DELAY ANY PRECIPITAITON
CHANCES UNTIL AFTER 06Z. 06.18Z NAM...06.12Z
ECMWF/CANADIAN...06.20/21Z HRRR AND 06.21Z/22Z RAP ALL KEEP ANY
ISENTROPICALLY INDUCED SHOWERS TO THE NORTH AND WEST OF THE
FORECAST AREA THROUGH 06Z. IN FACT...THE HRRR...RAP AND 06.12Z SPC
WRF-NMM SUGGEST THE FORECAST AREA MINUS TAYLOR/CLARK COUNTIES COULD
END UP DRY THROUGH SUNDAY MORNING. THIS WOULD MAKE SENSE TOO LOOKING
AT THE 06.18Z NAM 310-315K ISENTROPIC LIFT FIELDS. THESE FIELDS
SHOW LIFT...WHICH IS CURRENTLY HELPING TO PRODUCE THE ALTOSTRATUS
AND SOME SHOWER ACTIVITY BACK IN SOUTHWEST TO CENTRAL
MN...WEAKENING AS IT APPROACHES AND MOVES THROUGH THE AREA DURING
THE 9-18Z TIME PERIOD. IF MODEL TRENDS CONTINUE...MAY END UP
LOWERING PRECIPITATION CHANCES OR COMPELTELY DRYING OUT SOME OF
THE FORECAST BETWEEN 06-18Z.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 334 PM CDT SAT JUL 6 2013
LATEST WATER VAPOR IMAGERY SHOWED A CUTOFF LOW OVER THE MIDDLE
MISSISSIPPI RIVER VALLEY. TWO AREAS OF HIGH PRESSURE NOTED...ONE OFF
OF THE EAST COAST AND ANOTHER ANCHORED OVER NORTH CENTRAL MEXICO.
FLOW WAS TRANSITIONING TO ZONAL OVER THE PACIFIC NORTHWEST THROUGH
THE NORTHERN PLAINS. A SHORTWAVE WAS MOVING ACROSS NORTH DAKOTA
WITH ANOTHER WAVE NOTED OVER NORTHERN MINNESOTA. ANOTHER..WEAKER
WAVE WAS NOTED MOVING EAST ACROSS SOUTH DAKOTA. SURFACE
OBSERVATIONS SHOWED A WEAK FRONTAL BOUNDARY EXTENDING FROM CENTRAL
NORTH DAKOTA EAST THROUGH NORTHERN MINNESOTA.
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ACROSS EASTERN SOUTH
DAKOTA INTO CENTRAL AND PORTIONS OF NORTHERN MINNESOTA THIS
AFTERNOON. THIS ACTIVITY IS EXPECTED TO BECOME MORE WIDESPREAD THIS
EVENING AS 850 MB MOISTURE TRANSPORT INCREASES AND FOCUSES INTO
CENTRAL AND NORTHERN MINNESOTA. THE BULK OF THE ACTIVITY WILL BE
NORTHWEST OF THE FORECAST AREA INTO THE LATE EVENING HOURS. THE
MOISTURE TRANSPORT THEN ATTEMPTS TO SHIFT EAST EARLY SUNDAY MORNING
AS THE WEAK SHORTWAVE PUSHES EAST INTO THE UPPER MISSISSIPPI RIVER
VALLEY. INSTABILITY AND UPPER LEVEL FORCING IS REALLY WANING AS THE
MOISTURE TRANSPORT MOVES IN. THE WAVE DOES MAKE ITS WAY THROUGH THE
AREA SUNDAY MORNING WITH SCATTERED SHOWERS AND PERHAPS AN ISOLATED
THUNDERSTORM POSSIBLE. THE FRONTAL BOUNDARY SLIDES SOUTHEAST DURING
THE DAY ON SUNDAY AND BY LATE AFTERNOON IS EXPECTED TO STRETCH FROM
WEST CENTRAL IOWA NORTHEAST THROUGH NORTHWEST WISCONSIN. 0-3KM MUCAPE
CLIMBS TO AROUND 3000 J/KG AHEAD OF THE FRONT. HOWEVER...UPPER LEVEL
RIDGING IS OCCURRING DURING THIS TIME FRAME AND SHOULD ACT TO
SUPPRESS CONVECTION AT LEAST UNTIL LATE AFTERNOON WHEN A VERY WEAK
SHORTWAVE MOVES IN. THE FRONT PROGRESSES SOUTHEAST THROUGH THE
EVENING HOURS. ISOLATED THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT
BUT THINKING THEY WILL STRUGGLE TO DEVELOP WITH THE RIDGING
OCCURRING ALOFT. IF STORMS CAN OVERCOME THE RIDGING...CANNOT RULE
OUT AN ISOLATED SEVERE STORM OR TWO WITH LARGE HAIL AND DAMAGING
WINDS. HAVE MAINTAINED LOW THUNDERSTORM CHANCES THROUGH THE
AFTERNOON. PLAN ON HIGHS ON SUNDAY RANGING FROM THE LOWER 80S OVER
NORTH CENTRAL WISCONSIN TO THE UPPER 80S OVER PORTIONS OF
NORTHEAST IOWA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 334 PM CDT SAT JUL 6 2013
THE FRONT SLIDES SOUTH INTO NORTHERN IOWA AND NORTHERN ILLINOIS
SUNDAY NIGHT INTO MONDAY MORNING WITH THE HIGHER CHANCES FOR
SHOWERS AND STORMS FOCUSED ALONG THE FRONT LATE SUNDAY NIGHT. FLOW
ALOFT THEN FINALLY TURNS ZONAL ON MONDAY WITH EMBEDDED SHORTWAVES
INTERACTING WITH THE FRONT AS IT STARTS TO ACT AS A WARM FRONT.
PRECIPITABLE WATER VALUES HOVER AROUND 170 PERCENT OF NORMAL OVER
NORTHERN IOWA THROUGH SOUTHERN WISCONSIN LATE MONDAY AFTERNOON
THROUGH TUESDAY MORNING. 850 MB MOISTURE TRANSPORT FOCUSES INTO
THE THE FRONT MONDAY NIGHT INTO TUESDAY MORNING AND COLD LEAD TO
REPEATED ROUNDS OF SHOWERS AND STORM ALONG IT. WITH WARM CLOUD
DEPTHS IN THE 4000 TO 4200 METER RANGE...THE STORMS WILL BE
EFFICIENT RAIN PRODUCERS. WILL HAVE TO KEEP A VERY CLOSE EYE ON
THE POTENTIAL FOR HEAVY RAINFALL ALONG THIS FRONT. THERE ARE
SIGNALS SUGGESTING THE FRONT COULD STALL OVER NORTHEAST IOWA AND
SOUTHWEST WISCONSIN...LEADING THE POTENTIAL FOR FLASH FLOODING
FROM REPEATED ROUNDS OF STORMS MONDAY NIGHT INTO TUESDAY MORNING.
THE 18Z NAM IS A BIT FURTHER SOUTH PLACING THE WARM FRONT OVER
SOUTHERN IOWA WHICH WOULD PLACE THE THREAT FOR HEAVY RAIN CLOSER
TO THE INTERSTATE 80 CORRIDOR.
A SHORTWAVE TROUGH APPROACHES THE REGION FROM THE NORTHERN PLAINS
TUESDAY AFTERNOON. A COLD FRONT WILL PUSH SOUTH ACROSS THE NORTHERN
PLAINS AND INTO THE UPPER MISSISSIPPI RIVER VALLEY TUESDAY AFTERNOON
INTO TUESDAY EVENING. 0-3KM MUCAPE VALUES CLIMB INTO THE 1500 TO
2500 J/KG RANGE TUESDAY AFTERNOON AHEAD OF THE FRONT WHILE 0-6 KM
BULK SHEAR INCREASES TO AROUND 30 KTS. DEPENDING ON HOW LONG THE
MORNING CONVECTION HOLDS ON...SEVERE THUNDERSTORMS ARE A POSSIBILITY
TUESDAY AFTERNOON INTO TUESDAY EVENING. LARGE HAIL...DAMAGING WINDS
AND HEAVY RAINFALL WOULD BE THE MAIN HAZARDS. THE COLD FRONT THEN
SWEEPS SOUTH ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY MORNING AS
SURFACE HIGH PRESSURE BUILDS IN. QUIET WEATHER AND SEASONABLE
TEMPERATURES ARE EXPECTED IN THE WAKE OF THE FRONT FROM WEDNESDAY
AFTERNOON THROUGH FRIDAY WITH HIGHS IN THE 80S AND LOWS MAINLY IN
THE 60S. AN UPPER RIDGE BUILDS OVER THE REGION BRIEFLY LATE IN THE
WEEK...BUT THEN LOOKS TO BREAK DOWN LATE FRIDAY INTO SATURDAY AS A
SHORTWAVE MOVES ACROSS THE DAKOTAS AND INTO THE UPPER MISSISSIPPI
RIVER VALLEY BRINGING CHANCES FOR SHOWERS AND STORMS TO THE
AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 627 PM CDT SAT JUL 6 2013
A MORE DIFFICULT AVIATION FORECAST THIS TAF CYCLE...PRIMARILY WITH
WHETHER SHOWERS WILL IMPACT THE TAF SITES OR NOT. CLEAR SKIES
DOMINATE MUCH OF THE UPPER MISSISSIPPI RIVER VALLEY REGION AT
23Z...AHEAD OF A MASS OF ALTOSTRATUS AND SOME EMBEDDED SHOWERS
EXTENDING FROM NORTHEAST MN INTO NORTHWEST IA. MODELS HAVE SLOWED
THE TIMING OF THIS STRATUS AND PRECIPITATION EASTWARD BY 4 HOURS
OR SO...AND HAVE ADJUSTED THE AVIATION FORECASTS ACCORDINGLY.
HOWEVER...MODELS ARE ALSO SUGGESTING THAT THE SHOWERS MAY FALL
APART BEFORE REACHING EITHER TAF SITE. HAVE FOLLOWED THIS TREND BY
REMOVING ANY VISIBILITY RESTRICTIONS AND SWITCHING -SHRA TO VCSH.
THE ALTOSTRATUS SHOULD SCATTER OUT BETWEEN 15-17Z AS DRIER AIR
ALOFT FROM THE DAKOTAS MOVES IN. DURING THE LATE AFTERNOON...A
COLD FRONT SITUATED OVER CENTRAL MINNESOTA IS FORECAST TO DROP
DOWN INTO THE TAF SITES. HAVE NOT INCLUDED ANY SHOWERS OR
THUNDERSTORMS WITH IT DUE TO CAPPING CONCERNS. ONLY OTHER CHANGE
TO THE FORECAST WAS TO REMOVE GUSTS FOR BOTH TAF SITES ON SUNDAY.
THE PRESSURE GRADIENT LOOKS WEAKER AND THERE IS NOT AS MUCH WIND
TO MIX DOWN TO THE SURFACE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1148 PM CDT THU JUL 4 2013
.UPDATE...
ISSUED AT 557 PM CDT THU JUL 4 2013
SHOWERS HAVE DISSIPATED ACROSS THE FORECAST AREA...AIDED BY A
COMBINATION OF DEWPOINT MIXING...START OF COOLING NOW BEING PAST THE
TIME OF PEAK HEATING...AND OUTFLOWS FROM PREVIOUS SHOWERS PUSHING
EAST OF THE AREA. THEREFORE...HAVE REMOVED THE MENTION OF ANY
SHOWER ACTIVITY FROM THE FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM CDT THU JUL 4 2013
CURRENT WATER VAPOR IMAGERY SHOWED A BROAD TROUGH EXTENDING FROM
JAMES BAY SOUTH THROUGH WISCONSIN AND EXTENDING INTO THE CENTRAL
PLAINS. TWO EXPANSIVE UPPER RIDGES NOTED ONE ANCHORED OVER THE
SOUTHWEST CONUS...EXTENDING NORTH THROUGH THE ROCKIES AND ANOTHER
NOTED OFF THE EAST COAST...EXTENDING NORTH THROUGH NEW ENGLAND. A
SHORTWAVE WAS NOTED ALONG THE ONTARIO/MANITOBA BORDER EXTENDING
SOUTH INTO THE EASTERN DAKOTAS...DRIFTING SOUTHEAST. SURFACE
OBSERVATIONS PLACED A TROUGH OVER THE WESTERN DAKOTAS THROUGH
NORTH CENTRAL NEBRASKA SLOWLY SAGGING EAST. HIGH PRESSURE WAS
ANCHORED OFF OF THE EAST COAST...EXTENDING EAST INTO THE MID
MISSISSIPPI RIVER VALLEY.
FROM LATE THIS AFTERNOON INTO THIS EARLY EVENING...KEEPING A VERY
CLOSE EYE ON ISOLATED SHOWERS THAT HAVE DEVELOPED ALONG A WEAK
SHORTWAVE MOVING THROUGH ACROSS SOUTHWEST WISCONSIN. AN ISOLATED
THUNDERSTORM IS A ALSO POSSIBLE. THIS ACTIVITY WILL QUICKLY DIE
OFF AFTER WE LOSE SURFACE HEATING THIS EVENING. RUC ANALYSIS
SURFACE BASED CAPE VALUES HAVE CLIMBED TO AROUND 1500 J/KG WITH NO
CAP IN PLACE. 0-6 KM BULK SHEAR IS VERY WEAK SO NOT EXPECTING
SEVERE THUNDERSTORMS. GIVEN THE HIGH BASED NATURE OF THIS
ACTIVITY...WE COULD SEE SOME WIND GUSTS TO AROUND 35 MPH. AFTER
THIS ACTIVITY DISSIPATES THIS EVENING...LOOK FOR SKIES TO BECOME
MOSTLY CLEAR WITH OVERNIGHT LOWS FALLING INTO THE UPPER 50S ACROSS
PORTIONS OF NORTH CENTRAL INTO CENTRAL WISCONSIN.
THE SURFACE TROUGH EDGES SOUTHEAST ON FRIDAY PUSHING INTO THE
CENTRAL MINNESOTA AND FAR NORTHWEST WISCONSIN. MEANWHILE...THE
SHORTWAVE TROUGH WILL MOVE EAST ACROSS MINNESOTA AND INTO WISCONSIN
FRIDAY NIGHT. A TIGHT PRESSURE GRADIENT ACROSS THE REGION WILL
RESULT IN BREEZY SOUTH WINDS OF 15 TO 25 MPH WITH GUSTS AROUND 35
MPH IN THE OPEN AREAS OF SOUTHEAST MINNESOTA INTO NORTHEAST IOWA.
OTHERWISE...PLAN ON CLOUDS GRADUALLY INCREASING DURING THE AFTERNOON
HOURS AS THE UPPER LEVEL TROUGH DRAWS CLOSER. FORECAST SOUNDINGS
SHOW AFTERNOON CAPE VALUES CLIMB INTO THE 500 TO 1200 J/KG RANGE.
HOWEVER THERE APPEARS TO BE STRONGER CAPPING IN PLACE VERSUS
VS...4TH OF JULY AFTERNOON. AN ELEVATED MIXED LAYER MOVES BETWEEN
800 AND 900 MB AND SHOULD HELP TO STRENGTHEN THE CAP. THIS SHOULD
KEEP CONVECTION FROM FIRING BUT WILL HAVE TO KEEP A CLOSE ON THIS.
PLAN ON HIGH TEMPERATURES RANGING FROM THE LOWER TO MID 80S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 351 PM CDT THU JUL 4 2013
THE SURFACE TROUGH EDGES SOUTHEAST FRIDAY NIGHT INTO EARLY SATURDAY
MORNING MOVES ACROSS CENTRAL MINNESOTA INTO NORTHERN WISCONSIN. A
FEW SHOWERS AND THUNDERSTORMS COULD DEVELOP VERY LATE FRIDAY NIGHT
INTO EARLY SATURDAY MORNING AS THIS WAVE MOVES THROUGH. THIS
ACTIVITY WOULD IMPACT LOCATIONS MAINLY NORTH OF INTERSTATE 90. HAVE
ADDED A SLIGHT CHANCE FOR SHOWERS AND STORM ACROSS PORTIONS OF
SOUTHEAST MINNESOTA...WEST CENTRAL INTO NORTH CENTRAL WISCONSIN FROM
09Z TO 12Z THEN LINGERING FROM 12Z TO 15Z OVER NORTH CENTRAL
WISCONSIN BEFORE THE WAVE FINALLY SHIFTS EAST OF THE FORECAST AREA.
THE TROUGH STALLS OUT ON SATURDAY OVER CENTRAL MINNESOTA AND NORTHERN
WISCONSIN AND STARTS TO ACT AS A WARM FROM AS LOW PRESSURE DEEPENS
OVER THE HIGHS PLAINS. SOUTHERLY FLOW WILL BRING HIGHER DEWPOINTS
BACK INTO THE AREA ON SATURDAY...WITH VALUES CLIMBING INTO THE MID
TO UPPER 60S. AFTERNOON SURFACE BASED CAPE VALUES CLIMB INTO THE 1500
TO 1900 J/KG RANGE. THERE REALLY ISNT ANY APPRECIABLE FORCING TO
LATCH ONTO FOR STORMS TO BE TRIGGER BUT WITH ONLY A WEAK CAP IN
PLACE IT WON/T TAKE MUCH FOR THEM TO GO DURING THE AFTERNOON HOURS.
A STRONGER WAVE PUSHES DURING THE EVENING HOURS AND 850 MB MOISTURE
TRANSPORT RAMPS UP OVER CENTRAL INTO SOUTHERN MINNESOTA...EDGING
INTO THE FORECAST AREA. SHOWER AND THUNDERSTORM CHANCES INCREASE
THROUGH THE NIGHT ON SATURDAY AS THE SHORTWAVE PUSH EAST TOWARDS THE
MISSISSIPPI RIVER VALLY AND THE 850 MB MOISTURE TRANSPORT FOLDS OVER
THE EAST AND FOCUS INTO THE FORECAST AREA BY 12Z SUNDAY. 850 MB
MOISTURE TRANSPORT REMAINS FOCUSED INTO THE AREA THROUGH MUCH OF THE
DAY ON SUNDAY. PRECIPITABLE WATER VALUES CLIMB TO AROUND 160 PERCENT
OF NORMAL AND WARM CLOUD DEPTHS APPROACH 4KM...SO ANY THUNDERSTORM
ACTIVITY WOULD HAVE THE POTENTIAL TO PRODUCE HEAVY DOWNPOURS. 0-6 KM
BULK SHEAR IS RATHER WEAK AGAIN...SO WIDESPREAD SEVERE THUNDERSTORMS
ARE NOT EXPECTED...BUT WILL HAVE TO KEEP A CLOSE WATCH ON SHEAR
PROFILES LATE SATURDAY NIGHT GOING INTO SUNDAY. AN ACTIVE PATTERN
REMAINS IN PLACE OVER THE REGION GOING INTO THE WORK WEEK WITH DAILY
CHANCES FOR SHOWERS AND STORMS. A WARM FRONT STALLS OVER NORTHERN
IOWA/SOUTHERN WISCONSIN MONDAY INTO TUESDAY. A SHORTWAVE PUSHES INTO
THE AREA TUESDAY INTO WEDNESDAY. THERE AREA SOME UNCERTAINTIES
REGARDING THE TIMING OF THIS WAVE. HOWEVER...A SURFACE LOW LOOKS TO
DEVELOP OVER THE EASTERN DAKOTAS AND RACES EAST THROUGH THE AREA
TUESDAY AFTERNOON INTO TUESDAY EVENING. THIS SYSTEM HAS THE
POTENTIAL TO BRING SEVERE THUNDERSTORMS TO THE REGION AND
POTENTIALLY SUPERCELLS WITH 0-6 KM BULK SHEAR VALUES INCREASES TO TO
25 TO 35 KTS....SO KEEPING A CLOSE WATCH ON THIS TIMEFRAME.
SEASONABLE TEMPERATURES CAN BE EXPECTED THROUGH NEXT WEEK WITH HIGHS
IN THE 80S AND AND LOW MAINLY IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1148 PM CDT THU JUL 4 2013
DRY AIR IN THE LOWER LEVELS OF THE ATMOSPHERE...AHEAD OF A SLOWLY
EASTWARD MOVING COLD FRONT OVER THE DAKOTAS...WILL CONTINUE TO
PROMOTE VFR CONDITIONS AT BOTH TAF SITES THROUGH THIS EVENING.
NOTE...THOUGH...IT IS POSSIBLE FOR A FEW SHOWERS TO FORM OUT OF
AN ALTOSTRATUS DECK AT RST DURING THE EVENING. CONFIDENCE IS TOO
LOW TO INCLUDE VCSH AT THIS TIME. OTHERWISE WINDS REMAIN THE MAIN
CONCERN. THE PRESSURE GRADIENT HAS TIGHTENED AHEAD OF THE
FRONT. ONCE DAYTIME HEATING COMMENCES...EXPECT SOUTH WINDS TO
INCREASE WITH GUSTS OF 20-25 KT LIKELY IN THE AFTERNOON. THE GUSTS
WILL SUBSIDE AROUND 00Z WITH NIGHTTIME COOLING BEGINNING TO TAKE
PLACE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
322 PM MDT FRI JUL 5 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 315 PM MDT FRI JUL 5 2013
SHORTWAVE TROUGH IS MOVING ACROSS WESTERN WYOMING EARLY THIS AFTERNOON
WITH PLENTIFUL MOISTURE MOVING OVERHEAD IN WESTERLY FLOW ALOFT.
SCATTERED TO WIDESPREAD SHOWERS AND THUNDERSTORMS HAVE DEVELOPING
MAINLY ALONG AND WEST OF THE LARAMIE RANGE WITHIN THIS MOISTURE
PLUME AND WEAKLY UNSTABLE ENVIRONMENT...WITH BLENDED AMSU-SSM/I
PWATS ANALYZED TO BE AROUND 1 INCH. WILL CONTINUE TO SEE THIS AND
NEW DEVELOPMENT TREK EASTWARD THROUGH THE AFTERNOON AS THE UPPER
WAVE CONTINUES TO MOVE OVERHEAD AND FURTHER HEATING DESTABILIZES
THE EASTERN PLAINS. MESOANALYSIS AT 20Z SHOWS WEAK DEEP LAYER
SHEAR OVER THE FORECAST AREA WITH RAP FORECAST MAINTAINING SHEAR
OF ABOUT 35 KT OR LESS THROUGH THIS AFTERNOON...SO STORMS WILL
LIKELY REMAIN MODERATE TO HEAVY RAIN PRODUCERS WITH A FEW PRODUCING
SMALL HAIL AND GUSTY WINDS. ALL IN ALL...SOME MUCH NEEDED RAINS
WILL FALL OVER MUCH OF THE FORECAST AREA TODAY AND THIS EVENING.
THE DEEPEST OF THE MOISTURE PLUME WILL SHIFT EAST TONIGHT AND
TOMORROW ALTHOUGH STILL LOOKING AT PWATS TO BE ONE HALF INCH TO ONE
INCH FROM WEST TO EAST BY TOMORROW AFTERNOON. A WEAK COOL FRONT WILL
MOVE SOUTH ACROSS THE EASTERN PLAINS LATE TOMORROW MORNING WITH
WINDS SHIFTING TO THE NORTH THEN EAST BEHIND THE FRONT AS IT STALLS
ALONG THE LARAMIE RANGE. SHOULD SEE WEAK SHOWERS WITH PERHAPS A CLAP
OF THUNDER DEVELOP ALONG THE FRONT IN THE MORNING. A BROADER
COVERAGE OF STORMS WILL DEVELOP IN THE HIGH TERRAIN IN THE AFTERNOON
AS ANOTHER SHORTWAVE APPROACHES FROM THE WEST IN ADDITION TO WITHIN
THE CONVERGENCE ALONG THE LARAMIE RANGE. BULK SHEAR WILL BE ABOUT 10
KT HIGHER TOMORROW THAN TODAY SO COULD SEE MORE ORGANIZED STORMS
PRODUCE STRONGER WINDS AND PERHAPS LARGER HAIL. STILL NOT EXPECTING
ANYTHING SEVERE HOWEVER WITH WEAK INSTABILITY FORECAST...MORESO
AGAIN THE MAIN THREAT WITH THIS ACTIVITY WILL REMAIN MODERATE TO
HEAVY RAIN.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 315 PM MDT FRI JUL 5 2013
A CONSENSUS OF THE LATEST MEDIUM RANGE MODEL GUIDANCE SUGGESTS
THAT THE UNSETTLED WEATHER PATTERN WILL CONTINUE INTO THE EARLY
PART OF THE WEEK. A BROAD UPPER RIDGE WILL DOMINATE THE SOUTHERN
HALF OF THE CONUS WITH THE FASTER WESTERLIES CONFINED TO THE
NORTHERN STATES. A ZONAL FLOW ALOFT WILL TRANSPORT PACIFIC MOISTURE
AS WELL AS SOME SHORTWAVE ENERGY ACROSS THE REGION DURING THIS
TIME. SCATTERED DEEP MOIST CONVECTION WILL DEVELOP SUNDAY AND
MONDAY...MAINLY DURING THE AFTERNOON AND EVENING. BEST INSTABILITY
AND 0-6KM SHEAR (SBCAPES 1000-1500 J/KG AND 30-40 KT RESPECTIVELY)
WILL BE ALONG AN AXIS FROM NORTHEAST WYOMING THROUGH THE BLACK
HILLS AND WESTERN NEBRASKA BOTH SUNDAY AND MONDAY. SO THE POTENTIAL
WILL EXIST FOR ISOLATED STRONG TO SEVERE TSTORMS PRODUCING STRONG
WINDS AND HAIL. THIS WOULD INCLUDE AREAS EAST OF A LINE FROM
DOUGLAS TO TORRINGTON TO KIMBALL. HIGH PRECIP WATER VALUES (0.75
TO 1.25 INCHES) WILL YIELD EFFICIENT RAIN-PRODUCING STORMS.
TUESDAY...THE AXIS OF GREATER INSTABILITY AND SHEAR WILL BE LOCATED
OVER CENTRAL SOUTH DAKOTA AND NEBRASKA. SOMEWHAT DRIER AIR WILL
SPREAD EAST ACROSS THE CWA AT THAT TIME...LIMITING THE CONVECTION
TO ISOLATED MAINLY ALONG AND EAST OF THE MOUNTAINS. WEDNESDAY...
HIGHER INSTABILITY TRIES TO ADVECT NORTHWESTWARD INTO THE EASTERN
PLAINS DURING THE AFTERNOON AND EVENING. HOWEVER...WARMER AIR ALOFT
WILL ONCE AGAIN KEEP CONVECTION ISOLATED. CANNOT RULE OUT A FEW
STRONG TSTORMS. THURSDAY LOOKS DRY WITH THE UPPER RIDGE AND MID
LEVEL CAP SUPPRESSING CONVECTION. THE RIDGE AXIS SHIFTS EAST INTO
THE HIGH PLAINS FRIDAY WITH THE FLOW ALOFT BECOMING SOUTHWEST.
THIS MAY ADVECT SOME PACIFIC MOISTURE INTO THE CWA FOR ISOLATED
AFTERNOON CONVECTION OVER THE HIGHER TERRAIN. TEMPERATURES DURING
THE EXTENDED FORECAST PERIOD WILL CONTINUE TO AVERAGE ABOVE SEASONAL
NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1155 AM MDT FRI JUL 5 2013
SCATTERED SHOWERS AND TSTORMS WILL DEVELOP THIS AFTERNOON OVER THE
HIGH TERRAIN AND MOVE EAST ACROSS THE PLAINS THROUGH THE EVENING.
MVFR CIGS/VSBYS ARE POSSIBLE WITH THIS ACTIVITY ALONG WITH GUSTY
ERRATIC DOWNDRAFT WINDS. OTHERWISE VFR CONDITIONS WILL PREVAIL...
WITH GENERALLY BREEZY SOUTHWEST WINDS ALONG AND WEST OF THE LARAMIE
RANGE AND SOUTHEAST WINDS FURTHER EAST. A WEAK COOL FRONT MOVING
SOUTH ACROSS THE PLAINS SATURDAY MORNING WILL SHIFT WINDS TO THE
NORTHWEST...WITH GUSTS UP TO 20 MPH POSSIBLE BEHIND THE FRONT.
&&
.FIRE WEATHER...
ISSUED AT 315 PM MDT FRI JUL 5 2013
THE FIRE WEATHER THREAT WILL REMAIN MARGINAL THROUGH THE WEEKEND AS
PLENTIFUL AVAILABLE MOISTURE WILL MAINTAIN GOOD CHANCES FOR WETTING
RAINS OVER MUCH OF THE DISTRICT. THUNDERSTORMS SHOULD DEVELOP ACROSS
THE FORECAST AREA EACH AFTERNOON AND WILL PRODUCE GUSTY WINDS
ESPECIALLY WEST OF THE LARAMIE RANGE...ALONG WITH MODERATE TO
LOCALLY HEAVY RAINFALL AT TIMES. OTHERWISE...GENERAL WINDS WILL
REMAIN RELATIVELY LIGHT WITH A FEW LOCATIONS IN THE WIND PRONE
AREAS SEEING SOUTHWEST WINDS GUSTING TO 30 MPH IN THE AFTERNOON.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...MAJ
AVIATION...RJM
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS TUCSON AZ
921 PM MST SAT JUL 6 2013
.SYNOPSIS...A RIDGE OF HIGH PRESSURE WILL BUILD OVER THE DESERT
SOUTHWEST THIS WEEKEND EXPANDING EASTWARD EARLY NEXT WEEK. THIS
RIDGE WITH OCCASIONAL WEAK DISTURBANCES ROTATING AROUND
IT...COMBINED WITH MOISTURE ACROSS THE AREA WILL PROVIDE A CHANCE OF
SHOWERS AND THUNDERSTORMS EARLY IN THE NEW WEEK. INCREASED ACTIVITY
IS POSSIBLE THE SECOND HALF OF THE WEEK.
&&
.DISCUSSION...WATER VAPOR IMAGERY SHOWS A SWATH OF MID LEVEL DRY AIR
ACROSS MUCH OF THE EASTERN PACIFIC...CALIFORNIA...NORTHERN SONORA
MEXICO AND SOUTHWEST ARIZONA. MEANWHILE...MORE MOIST AIR RESIDES TO
THE EAST AND THIS INTERFACE BETWEEN THE DRIER AND MORE MOIST AIR IS
SERVING AS A FOCUS FOR CONVECTIVE DEVELOPMENT WHICH TRIGGERED STORMS
SOUTH OF NOGALES AND ALSO OVER THE TOHONO O`ODHAM NATION...CENTRAL
PIMA COUNTY AND WESTERN PORTIONS OF PINAL COUNTY. THIS CLUSTER OF
STORMS WILL CONTINUE TO MOVE TO THE NORTH BETWEEN MARANA AND CASA
GRANDE THIS EVENING.
ELSEWHERE ACROSS SOUTHEAST ARIZONA ISOLATED THUNDERSTORMS HAVE
RECENTLY DEVELOPED ALONG THE ARIZONA/NEW MEXICO BORDER...ALONG
INTERSTATE 10 NEAR SAN SIMON...AND THESE STORMS ARE ALSO MOVING
NORTH.
THE RUC HRRR MODEL INDICATED THAT THE CLUSTER OF STORMS NORTHWEST OF
TUCSON AND INTO PINAL COUNTY WILL CONTINUE TO MOVE NORTH AND OUT OF
MY FORECAST AREA THIS EVENING...WITH NO SIGNIFICANT DEVELOPMENT
THEREAFTER. HOWEVER...GIVEN THE STORMS ALONG THE NEW MEXICO
BORDER...AND OLD OUTFLOW BOUNDARIES MOVING HERE AND THERE...WILL
KEEP SOME MENTION OF ISOLATED SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH THE REMAINDER OF THE NIGHT.
AS OF 04Z (9 PM MST)...TEMPERATURES ACROSS THE REGION RANGED FROM
THE MID 70S TO THE LOWER 90S...WITH THE TUCSON INTL AIRPORT
REPORTING A TEMP OF 93 DEGS AFTER REACHING A HIGH OF 103 DEGS. THESE
CURRENT READINGS SEEM TO BE ON TRACK WITH REGARD TO THE OVERNIGHT
LOWS...SO NO CHANGES ARE PLANNED AT THIS TIME...BUT WILL CONTINUE TO
MONITOR.
&&
.AVIATION...ISOLATED TO SCATTERED T-STORMS MAINLY NORTHWEST OF
TUCSON THROUGH AROUND 06Z...THEN ONLY EXPECTING ISOLATED TSTMS
THEREAFTER. WIND GUSTS WILL APPROACH 40-45 KTS WITH THE STRONGEST
TSTMS THROUGH 06Z. OTHERWISE...VFR CONDITIONS WITH DIURNALLY DRIVEN
WINDS TO OCCUR THRU SUNDAY AFTERNOON. ANOTHER ROUND OF ISOLATED TO
SCATTERED TSTMS DEVELOPING AGAIN LATE SUNDAY AFTERNOON AND INTO THE
EVENING HOURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...ON SUNDAY...EXPECT ISOLATED TO SCATTERED
AFTERNOON/EVENING THUNDERSTORMS. THEREAFTER...SCATTERED MAINLY
AFTERNOON AND EVENING THUNDERSTORMS WILL OCCUR DURING THE UPCOMING
WEEK FROM TUCSON EASTWARD...WITH ISOLATED THUNDERSTORMS WEST OF
TUCSON. THE STRONGER THUNDERSTORMS WILL PRODUCE STRONG...GUSTY AND
ERRATIC WINDS. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL OCCUR
THIS WEEKEND AND DURING THE UPCOMING WEEK. DAYTIME RELATIVE
HUMIDITIES NEXT WEEK WILL RANGE FROM THE MID TEENS TO 20S WITH GOOD
NIGHTTIME RECOVERIES.
&&
.CLIMATE...TODAY HAS BEEN THE 36TH CONSECUTIVE DAY WITH TEMPERATURES
IN EXCESS OF 100 DEGREES AT TUCSON INTERNATIONAL AIRPORT...4TH
LONGEST ALL TIME.
&&
.PREVIOUS DISCUSSION...WITH WEAK FLOW AND STRUCTURE WE WILL PROBABLY
LIMP ALONG AT A LOW GRADE THUNDERSTORM FORECAST TO START THE NEW
WEEK. THE HIGH PRESSURE AND LESS PERVASIVE CLOUD COVER SHOULD ALLOW
FOR TEMPERATURES ON THE HOTTER SIDE 5 TO 8 DEGREES ABOVE CLIMO.
SURGE ACTIVITY ASSISTED BY TROPICAL INFLUENCES AS EARLY AS TUESDAY
NIGHT WITH AN INVERTED TROUGH PUSHING ACROSS PORTIONS OF NORTHWEST
MEXICO BY MID WEEK.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
CURRENT DISCUSSION...MOLLERE
PREVIOUS DISCUSSION...MEYER/GLUECK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1119 PM MDT SAT JUL 6 2013
.UPDATE...
ISSUED AT 725 PM MDT SAT JUL 6 2013
UPDATED TO BUMP UP POPS ACROSS THE FAR EASTERN PLAINS WHERE
CLUSTER OF SHOWERS/THUNDERSTORMS CONTINUES. 23Z HRRR SLOWLY SHIFTS
THIS EASTWARD AND HANGS ON TO SOME SPOTTY QPF NEAR THE EASTERN
BORDER AFTER MIDNIGHT. IT ALSO DEVELOPS ANOTHER BAND OF
SHOWERS/EMBEDDED THUNDERSTORMS ACROSS THE CENTRAL MOUNTAINS WHICH
SHIFTS INTO THE SOUTHEAST MOUNTAINS AROUND 06Z BEFORE DIMINISHING
AS IT HEADS EASTWARD ACROSS THE SOUTHERN I-25 CORRIDOR AFTER 10Z.
SO FAR...HRRR SEEMS OVERDONE WITH THIS LATER BATCH OF
CONVECTION...BUT HAVE INTRODUCED SOME ISOLATED POPS OVER THE
MOUNTAIN AREAS THROUGH 08Z TO ACCOUNT FOR THE POSSIBILITY OF
LINGERING CONVECTION WITHIN MOISTURE PLUME. WILL WAIT FOR 00Z
NAM12 RUN TO ARRIVE BEFORE EXTENDING POPS THROUGH THE NIGHT FOR
MOST AREAS AS HRRR SUGGESTS. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM MDT SAT JUL 6 2013
...EARLY GLIMPSE OF THE MONSOON UNDERWAY...
EARLY MONSOONAL AIRMASS OVER SOUTHERN COLORADO THIS WEEKEND WITH
SURFACE DEWS NOW IN THE 40S AND 50S PRETTY MUCH ANY WHICH WAY YOU
LOOK. ALOFT...PLENTY OF MID/HIGH LEVEL MONSOON MOISTURE CIRCULATING
AROUND LARGE MEW MEXICO HIGH PRESSURE AREA. VERY LITTLE COLD AIR
ALOFT ASSOCIATED WITH LARGE HIGH SETTING THE STAGE FOR TYPICAL
DIURNAL AFTERNOON AND EVENING THUNDERSTORM ACTIVITY PRODUCING MOSTLY
RAIN AND MAYBE A LITTLE BIT OF SMALL HAIL...WITH OTHER THREATS
INCLUDING LIGHTNING AND LOCALLY GUSTY WINDS UP TO AROUND 50 MPH.
MONSOONAL MOISTURE IS NOT REAL GREAT YET...WITH PRECIPITABLE WATERS
RANGING FROM A SOUTHERN COLORADO MAX OF A LITTLE OVER AN INCH ACROSS
THE SOUTHEAST TIP OF BACA COUNTY TO A MIN AROUND 3 QUARTERS OF AN
INCH ACROSS THE NORTHWEST TIP OF LAKE COUNTY. BUT...SURELY BETTER
THAN A COUPLE DAYS AGO...AND ADEQUATE FOR SOME LOCALLY HEAVY
RAINERS. THERE IS CERTAINLY ENOUGH WATER IN THE ATMOSPHERE FOR
CONCERN OVER SOME OF THE NEWER AREA BURN SCARS INCLUDING THE
WALDO...EAST PEAK AND WEST FORK SCARS. VIGILANCE MUST CONTINUE IN
THESE AREAS FOR THE FORESEEABLE FUTURE...STARTING WITH THIS
AFTERNOON AND EVENING.
AS IN RECENT DAYS...MOST THUNDERSTORM ACTIVITY SHOULD DIE DOWN
ACROSS THE AREA BY AROUND 04Z OR SO...WITH CONVECTIVE DEBRIS
LINGERING AND GRADUALLY DISSIPATING AFTER THAT. FEEL THAT MOST
ACTIVITY WILL BE COMPLETELY OVER BY MIDNIGHT...ALTHOUGH THERE COULD
BE A FEW STRAGGLERS THROUGH THE NIGHT...COVERING LESS THAN ONE
PERCENT OF THE FORECAST AREA. LW
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM MDT SAT JUL 6 2013
...MONSOON SEASON IS UPON US...
LOOKS LIKE A FAIRLY NORMAL SUMMER PATTERN WILL BE WITH US FOR THE
COMING WEEK. FORECAST TEMPS AND PRECIP WILL BE INFLUENCED BY THE
OVERALL PATTERN...INCLUDING THE POSITION OF THE RIDGE AND H5 HIGH
OVER THE SW U.S. THE UPPER HIGH WILL START OFF OVER THE 4 CORNERS
REGION ON MONDAY AND TUESDAY. THIS CAN BE A FAVORABLE MONSOONAL
PATTERN...BUT IN THIS PARTICULAR CASE THE UPPER RIDGE WILL BE
FLATTENED BY A SHORT WAVE MOVING THROUGH SW AND SRN CANADA...SO
UPPER WINDS WILL BE GENERALLY WESTERLY AND BRINGING RELATIVELY DRY
AIR IN FROM THE W AND SW. HOWEVER...THE SHORTWAVE COULD SPARK A FEW
HIGH BASED STORMS...PARTICULARLY OVER THE ERN MTS AND PLAINS LATE
MONDAY AND AGAIN ON TUESDAY.
TUESDAY NIGHT...A WEAK FRONT ASSOCIATED WITH THE SHORT WAVE NOW
MOVING INTO THE GREAT LAKES REGION WILL PUSH OVER ERN CO. THE UPPER
HIGH WILL HAVE MIGRATED SLIGHTLY EWD INTO NW NM. THIS WILL SET THE
STAGE FOR AN UP-TICK IN PRECIP ON WED...ESPECIALLY OVER THE MTS BUT
EXTENDING EWD ONTO THE PLAINS BY WED EVE.
THURSDAY...THE MONSOON PLUME RETURNS TO WRN CO AS THE UPPER HIGH
CONTINUES TO DRIFT SLIGHTLY TO THE W OVER NRN NM. A FAIRLY ROBUST
MOISTURE PLUME THEN LOOKS TO AFFECT THE AREA FRI AND THROUGH THE
WEEKEND. AT THIS TIME...IT LOOKS LIKE THE BULK OF THE HEAVIER
CONVECTION WILL BE OVER THE CENTRAL MTS...WHICH COULD BRING AN
INCREASED THREAT OF FLASH FLOODING TO THE MT AREAS...AND
PARTICULARLY THE WEST FORK BURN...THROUGH THE WEEKEND.
DAYTIME HIGH TEMPS WILL BE A BIT TRICKY TO FORECAST THIS COMING
WEEK. THE H5 HEIGHTS AND H7 TEMPS JUSTIFY HIGH TEMPS IN THE UPPER
90S OR EVEN LOW 100S FOR SEVERAL DAYS OVER THE LOWER ARKANSAS AND
ERN PLAINS. AT THIS TIME...SINCE THE MONSOONAL MOISTURE APPEARS TO
AFFECT MAINLY THE CENTRAL MTS...IF IT STAYS DRY ENOUGH THESE HIGH
TEMPS WILL BE REALIZED...AND THIS IS WHERE THE FORECAST TREND HAS
BEEN FOR THE DAILY HIGHS. HOWEVER...IT DOES APPEAR THAT AT LEAST
MODEST MID LEVEL MOISTURE WILL BE TRAPPED UNDER THE RIDGE...AND
COULD BRING AT LEAST ISOLD TO SCT CONVECTION OVER THE PLAINS EACH
DAY. IF THIS HAPPENS...THEN THE DAY TIME HIGHS COULD BECOME A RACE
BETWEEN REALIZING THE WELL MIXED VALUES DOWN FROM H7-H5...AND THE
DEVELOPMENT OF EARLY AFTERNOON THUNDERSTORMS...WHICH COULD BRING
DOWN TEMPS IN A HURRY FOR THE PLAINS. HOPEFULLY...THE PLUME WILL
SHIFT FAR ENOUGH E AT SOME POINT THAT MORE DEEP MOISTURE CAN MOVE
OVER THE PLAINS. ROSE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1116 PM MDT SAT JUL 6 2013
VFR CONDITIONS EXPECTED ACROSS THE FORECAST AREA...INCLUDING THE 3
MAIN TAF SITES OF KCOS...KPUB AND KALS...FOR THE NEXT 24 HRS.
THERE IS THE THREAT OF ISOLATED TO SCATTERED CONVECTION FIRING
OVER THE HIGHER TERRAIN EACH AFTERNOON...THEN MOVING EAST ACROSS
THE ADJACENT PLAINS THROUGH THE LATE AFTERNOON AND EARLY EVENING.
PRIMARY STORM THREATS INCLUDE LIGHTNING...PERIODS OF HEAVY
RAIN...AND GUSTY ERRATIC WINDS UP TO 50 MPH.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KT
SHORT TERM...LW
LONG TERM...ROSE
AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS ALBANY NY
210 AM EDT SUN JUL 7 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL BEGIN TO WEAKEN AND MOVE A LITTLE FURTHER
SOUTHEAST TODAY. THIS WILL ALLOW MOISTURE TO MOVE BACK INTO THE
REGION ON SUNDAY...INCREASING THE RISK OF SHOWERS AND THUNDERSTORMS.
SUNDAY NIGHT INTO MONDAY...AN UPPER LEVEL DISTURBANCE WILL MOVE BACK
INTO FROM THE OHIO VALLEY...KEEPING OUR WEATHER UNSETTLED.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1240 PM EDT...ALL STILL QUITE ON OUR RADAR. A MOSTLY CLEAR SKY
ALLOWING TEMPERATURES TO FALL A LITTLE DOWN INTO THE 70S IN THE
URBAN AREAS...60S OUTLYING REGION. NO FOG YET...BUT WITH
TEMPERATURES CLOSING TOWARD THE DEWPOINT IN SOME CASES...SOME PATCHY
FOG LOOKS LIKELY TOWARD DAYBREAK.
THERE ARE A FEW SHOWERS UPSTREAM ACROSS SOUTH CENTRAL NEW YORK
STATE...SLOWLY HEADING THIS WAY. ONE OF OUR EXPERIMENTAL NEAR TERM
MODELS THE HRRR INDICATED THESE WOULD COME INTO THE OUR REGION
BEFORE SUNRISE...PASSING THE CAPITAL REGION AFTER 800 AM AS HEAVY
SHOWERS POSSIBLY EVEN A THUNDERSTORM.
NOT SEEING IT THOUGH AS INSTABILITY IS LIMITED FROM THE CAPITAL
REGION NORTHWARD...ALTHOUGH SOME REMAINS TO OUR SOUTH (UP TO 1000
J/KG OFF THE LAPS). WITH HIGH PRESSURE IN PLACE...BELIEVE THE
SHOWERS WILL INITIALLY HAVE A HARD TIME HEADING OUR WAY...AT LEAST
THROUGH THE OVERNIGHT.
WILL KEEP POPS BELOW 15 PERCENT...ESSENTIALLY DRY. HOWEVER...WILL
CONTINUE TO INTRODUCE SLIGHT POPS AFTER SUNRISE AND SPREAD THEM
EASTWARD WITH TIME.
UPDATED TEMPS/DEW POINTS/CLOUDS TO REFLECT CURRENT OBS.
OTHERWISE...NO ADDITIONAL CHANGES.
WITH THE LIGHT WINDS AND HUMIDITY...TEMPERATURES SHOULD NOT COOL
OFF TOO MUCH FROM HOT EVENING TEMPERATURES DUE TO THE SHORT NIGHTS
THIS TIME OF YEAR...EVEN WITH THE PARTLY CLOUDY TO CLEAR SKY. SOME
PATCHY FOG IS ALSO POSSIBLE IN SOME AREAS. LOWS SHOULD BE IN THE
60S TO AROUND 70...WHICH IS A LITTLE COOLER THAN LAST NIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
UPPER ENERGY IN THE MIDWEST AND OH VALLEY SHOULD MOVE STEADILY
EAST AND THERE IS A GOOD CONSENSUS THAT ONE UPPER IMPULSE AT THE
LEADING EDGE OF THIS UPPER ENERGY SHOULD TRACK ACROSS THE REGION
TOMORROW AFTERNOON. THIS UPPER ENERGY SHOULD SUPPORT BETTER
COVERAGE OF SHOWERS AND THUNDERSTORMS TOMORROW AFTERNOON AND
EVENING OVER EASTERN NY INTO THE NORTHERN BERKSHIRES AND SOUTHERN
VT. ACTIVITY COULD BE LIMITED IN THE MID HUDSON VALLEY AND NW CT
SINCE THE UPPER ENERGY IS PREDICTED TO TRACK THROUGH MAINLY
NORTHERN AND CENTRAL AREAS. HIGHS SUNDAY IN THE 80S TO LOWER
90S...WITH THE WARMEST TEMPERATURES IN THE MID HUDSON VALLEY AND
NW CT.
THE MAIN CENTER OF THE UPPER ENERGY TRACKS JUST SOUTH OF THE
REGION MONDAY AND MONDAY AFTERNOON...BUT LOW LEVEL FORCING WITH A
LITTLE BIT OF COOLING AT THE BOUNDARY LAYER AND THE UPPER DYNAMICS
SHOULD SUPPORT INCREASED COVERAGE OF CLOUDS...SHOWERS AND
THUNDERSTORMS. HIGHS MONDAY SHOULD BE IN THE MID 80S...NEAR 80 IN
THE SOUTHERN ADIRONDACKS AND UPPER 80S MID HUDSON VALLEY AND NW
CT. LOCALLY HEAVY RAIN BOTH SUNDAY AND MONDAY COULD RESULT IN
LOCALIZED FLASH FLOODING AND A WATCH COULD BE CONSIDERED OVERNIGHT
OR TOMORROW DEPENDING ON HOW MUCH COVERAGE OF SHOWERS AND
THUNDERSTORMS COULD BE EXPECTED...SO STAY TUNED.
THERE ARE INDICATIONS THAT THE UPPER ENERGY AND WEAK COLD FRONT
EXIT THE REGION MONDAY NIGHT...WITH SOME POTENTIAL PARTIAL
CLEARING OUTSIDE OF AREAS OF FOG BY EARLY TUESDAY MORNING. LOWS
SHOULD BE IN THE 60S...WITH MAYBE SOME MID TO UPPER 50S IN THE
SOUTHERN ADIRONDACKS. ON TUESDAY...SOME WEAK UPPER RIDGING SHOULD
BE OVER THE REGION...BUT THE ATMOSPHERE SHOULD STILL BE UNSTABLE...
EVEN WITH NO REAL ORGANIZED LOW LEVEL FOCUS. SO...THERE COULD BE
ISOLATED SHOWERS AND THUNDERSTORMS IN THE SOUTHERN HALF OF THE
FORECAST AREA WITH HIGHS IN THE 80S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE PERIOD STARTS OUT LATE TUESDAY NIGHT INTO WEDNESDAY WITH A WARM
FRONT AND/OR PRE-FRONTAL TROUGH APPROACHING THE AREA FROM THE GREAT
LAKES AND OHIO VALLEY. THIS SYSTEM WILL BRING ADDITIONAL CHANCES FOR
AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS. THE EVENTUAL INTENSITY
OF T-STORMS WILL DEPEND ON THE DEGREE OF INSTABILITY...WHICH WILL BE
TIED TO CLOUD COVER. THERE SHOULD BE DECENT FLOW ALOFT FOR MID JULY
WITH A MIGRATORY SUB-1000MB CYCLONE TRACKING EASTWARD NEAR HUDSON
BAY.
THE FIRST SERIES OF FRONTAL BOUNDARY WILL PASS THROUGH BY SOMETIME
LATE WEDNESDAY OR WEDNESDAY NIGHT...WHILE THE MAIN COLD FRONT IS
FORECAST TO SAG SOUTHWARD ACROSS THE AREA LATE WEDNESDAY NIGHT INTO
THURSDAY. WILL CONTINUE TO MENTION CHANCE POPS DURING THIS
TIME...WITH THE POSSIBLY MORE ROBUST CONVECTION OCCURRING ON
WEDNESDAY. THERE COULD BE AN ADDITIONAL ROUND OF T-STORMS SOUTH OF
ALBANY ON THURSDAY IF THE FRONT SLOWS ENOUGH...WHICH IS BEING
DEPICTED BY THE 12Z GFS AND ECMWF.
IT AT LEAST LOOKS LIKE TEMPERATURES AND HUMIDITY LEVELS WILL START
TO SOMEWHAT DROP BY WEEK`S END AS A COOLER NORTHERLY FLOW DEVELOPS
IN WAKE OF THE COLD FRONT. HOWEVER...THE CHAOTIC UPPER LEVEL PATTERN
MAY ALLOW FOR A CUT-OFF LOW TO FORM SOMEWHAT IN THE VICINITY OF THE
OHIO VALLEY...MID ATLANTIC...OR SOUTHERN APPALACHIANS REGION WHICH
COULD RESULT IN A MOIST SOUTHERLY FLOW QUICKLY RETURNING BY THE
WEEKEND ALONG WITH RENEWED CHANCES FOR PRECIP AND INCREASING
HUMIDITY.
THERE STILL CONSIDERABLE UNCERTAINTY IN HOW THE PATTERN WILL
EVENTUALLY UNFOLD...BUT BOTH THE GFS AND ECMWF ARE DEPICTING A
CUT-OFF LOW FORMING SOUTH AND WEST OF OUR AREA NEXT WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z KGFL/KPOU HAD ALREADY HAD OCCASIONAL IFR VSBYS DUE TO
FOG...WHILE NO FOG HAD BEEN REPORTED AT KALB/KPSF. STLT PICS SHOW A
WIDESPREAD CLOUD DECK (GENERALLY MID/HI CLOUDS) MOVING OVER THE TAF
SITES AS OF 06Z AND WOULD EXPECT THIS CLOUD DECK TO INHIBIT FOG
FORMATION IF FOG HAD NOT LREADY FORMED BEFORE IT ARRIVES. WILL
CONTINUE TO FORECAST OCNL IFR FOG AT KGFL/KPOU THROUGH 11Z...BUT
FORECAST NO FOG AT KALB AND ONLY OCCASIONAL MVFR FOG AT KPSF.
THERE ARE SCT TO NUMEROUS SHWRS/TSTMS OVER FAR WESTERN NEW YORK AS
OF 06Z...WITH ISOLATED SHOWERS FURTHER EAST. THESE SHOWERS ARE
ASSOCIATED WITH AN APPROACHING UPPER LEVEL TROF. WOULD NOT EXPECT
THESE SHOWERS TO BE NEAR THE TAF SITES BEFORE MID OR LATE SUNDAY
MORNING. MODEL FORECASTS AND OBSERVED MOVEMENT OF THESE SHWRS/TSTMS
WOULD SUGGEST THE BULK OF THEM WILL PASS TO THE NORTH AND WEST OF
THE TAF SITES. AS A RESULT...WILL FORECAST NO MORE THAN VCSH IN THE
TAFS FROM LATE THIS MORNING THROUGH THE END OF THE TAF PERIOD AT 06Z
MONDAY. ALSO...EXCEPT FOR THE EARLY MORNING FOG CONDITIONS...HAVE
FORECAST VFR CONDITIONS AT THE TAF SITES THROUGH THE END OF THE TAF
PERIOD.
SURFACE WIND WILL GENERALLY BE CALM THROUGH 2 TO 3 HOURS AFTER
SUNRISE...THEN BECOME SOUTH OR SOUTHWEST AT 5 TO 10 KTS...THEN
BECOME LIGHT AGAIN AFTER SUNSET ON SUNDAY.
OUTLOOK...
LATE SUN NITE-TUE...MAINLY VFR. SCT MAINLY AFTERNOON AND EVENING
SHRA/TSRA. POSSIBLE LATE NIGHT AND/OR EARLY MORNING FOG/LOW STRATUS
WITH MVFR/IFR POSSIBLE.
WED...VFR/MVFR/IFR DUE TO SCT TO NUMEROUS SHRA/TSRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
FUELS CONTINUE TO REMAIN SATURATED FROM RECENT SHOWER/THUNDERSTORM
ACTIVITY. THERE WILL CONTINUE TO BE A CHANCE FOR AFTERNOON/EVENING
SHOWERS AND THUNDERSTORMS FOR THE NEXT SEVERAL DAYS AS THE BERMUDA
HIGH KEEPS A HOT AND HUMID AIR MASS ENTRENCHED OVER THE REGION.
NORMAL RH RECOVERIES EACH NIGHT BETWEEN 80 TO 100 PERCENT WILL ALLOW
FOR WIDESPREAD DEW FORMATION. DAYTIME RH VALUES WILL GENERALLY BE IN
THE 40 TO 60 PERCENT RANGE.
&&
.HYDROLOGY...
THE MOHAWK RIVER AT UTICA CONTINUES TO EXPERIENCE MINOR FLOODING.
THE RIVER AND CREEK FLOWS NEAR THE WEST CENTRAL MOHAWK RIVER ARE
EXPECTED TO GRADUALLY RECEDE INTO THE WEEKEND...UNLESS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS OCCUR OVER OR NEAR THE BASIN.
THERE COULD BE SCATTERED SHOWERS AND THUNDERSTORMS SUNDAY
AFTERNOON AND EVEN MORE COVERAGE OF SHOWERS AND THUNDERSTORMS
MONDAY AFTERNOON AND EVENING WITH THE APPROACH OF A WEAK COLD
FRONT. A MOIST AND HUMID AIR MASS WILL ALLOW ANY SHOWER OR
THUNDERSTORM TO BE CAPABLE OF PRODUCING LOCALLY HEAVY
DOWNPOURS...AND A QUICK INCH OR MORE OF RAINFALL DUE TO THE
ANOMALOUS PRECIPITABLE WATER VALUES.
THERE WILL BE A CONTINUED THREAT FOR ISOLATED FLASH FLOODING...AS
WELL AS FLOODING OF POOR DRAINAGE AND LOW LYING AREAS. NO FLASH
FLOOD WATCHES ARE BEING ISSUED DUE TO THE EXPECTED ISOLATED NATURE
OF ANY FLOODING. IT IS ALSO DIFFICULT TO DETERMINE WHERE THE
HEAVIEST RAINFALL WILL OCCUR.
WHILE ADDITIONAL FLOODING IS NOT ANTICIPATED ON ANY MAIN STEM RIVER
POINTS...LOCALLY SHARP RISES ARE POSSIBLE DUE TO ANY CONVECTION THAT
MAY OCCUR OVER THE NEXT SEVERAL DAYS...ESPECIALLY FOR THOSE POINTS
THAT ARE MORE FLASHIER IN NATURE.
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...HWJIV
NEAR TERM...HWJIV/OKEEFE
SHORT TERM...NAS
LONG TERM...JPV
AVIATION...GJM
FIRE WEATHER...NAS
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1237 AM EDT SUN JUL 7 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL BEGIN TO WEAKEN AND MOVE A LITTLE FURTHER
SOUTHEAST TODAY. THIS WILL ALLOW MOISTURE TO MOVE BACK INTO THE
REGION ON SUNDAY...INCREASING THE RISK OF SHOWERS AND THUNDERSTORMS.
SUNDAY NIGHT INTO MONDAY...AN UPPER LEVEL DISTURBANCE WILL MOVE BACK
INTO FROM THE OHIO VALLEY...KEEPING OUR WEATHER UNSETTLED.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1240 PM EDT...ALL STILL QUITE ON OUR RADAR. A MOSTLY CLEAR SKY
ALLOWING TEMPERATURES TO FALL A LITTLE DOWN INTO THE 70S IN THE
URBAN AREAS...60S OUTLYING REGION. NO FOG YET...BUT WITH
TEMPERATURES CLOSING TOWARD THE DEWPOINT IN SOME CASES...SOME PATCHY
FOG LOOKS LIKELY TOWARD DAYBREAK.
THERE ARE A FEW SHOWERS UPSTREAM ACROSS SOUTH CENTRAL NEW YORK
STATE...SLOWLY HEADING THIS WAY. ONE OF OUR EXPERIMENTAL NEAR TERM
MODELS THE HRRR INDICATED THESE WOULD COME INTO THE OUR REGION
BEFORE SUNRISE...PASSING THE CAPITAL REGION AFTER 800 AM AS HEAVY
SHOWERS POSSIBLY EVEN A THUNDERSTORM.
NOT SEEING IT THOUGH AS INSTABILITY IS LIMITED FROM THE CAPITAL
REGION NORTHWARD...ALTHOUGH SOME REMAINS TO OUR SOUTH (UP TO 1000
J/KG OFF THE LAPS). WITH HIGH PRESSURE IN PLACE...BELIEVE THE
SHOWERS WILL INITIALLY HAVE A HARD TIME HEADING OUR WAY...AT LEAST
THROUGH THE OVERNIGHT.
WILL KEEP POPS BELOW 15 PERCENT...ESSENTIALLY DRY. HOWEVER...WILL
CONTINUE TO INTRODUCE SLIGHT POPS AFTER SUNRISE AND SPREAD THEM
EASTWARD WITH TIME.
UPDATED TEMPS/DEW POINTS/CLOUDS TO REFLECT CURRENT OBS.
OTHERWISE...NO ADDITIONAL CHANGES.
WITH THE LIGHT WINDS AND HUMIDITY...TEMPERATURES SHOULD NOT COOL
OFF TOO MUCH FROM HOT EVENING TEMPERATURES DUE TO THE SHORT NIGHTS
THIS TIME OF YEAR...EVEN WITH THE PARTLY CLOUDY TO CLEAR SKY. SOME
PATCHY FOG IS ALSO POSSIBLE IN SOME AREAS. LOWS SHOULD BE IN THE
60S TO AROUND 70...WHICH IS A LITTLE COOLER THAN LAST NIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
UPPER ENERGY IN THE MIDWEST AND OH VALLEY SHOULD MOVE STEADILY
EAST AND THERE IS A GOOD CONSENSUS THAT ONE UPPER IMPULSE AT THE
LEADING EDGE OF THIS UPPER ENERGY SHOULD TRACK ACROSS THE REGION
TOMORROW AFTERNOON. THIS UPPER ENERGY SHOULD SUPPORT BETTER
COVERAGE OF SHOWERS AND THUNDERSTORMS TOMORROW AFTERNOON AND
EVENING OVER EASTERN NY INTO THE NORTHERN BERKSHIRES AND SOUTHERN
VT. ACTIVITY COULD BE LIMITED IN THE MID HUDSON VALLEY AND NW CT
SINCE THE UPPER ENERGY IS PREDICTED TO TRACK THROUGH MAINLY
NORTHERN AND CENTRAL AREAS. HIGHS SUNDAY IN THE 80S TO LOWER
90S...WITH THE WARMEST TEMPERATURES IN THE MID HUDSON VALLEY AND
NW CT.
THE MAIN CENTER OF THE UPPER ENERGY TRACKS JUST SOUTH OF THE
REGION MONDAY AND MONDAY AFTERNOON...BUT LOW LEVEL FORCING WITH A
LITTLE BIT OF COOLING AT THE BOUNDARY LAYER AND THE UPPER DYNAMICS
SHOULD SUPPORT INCREASED COVERAGE OF CLOUDS...SHOWERS AND
THUNDERSTORMS. HIGHS MONDAY SHOULD BE IN THE MID 80S...NEAR 80 IN
THE SOUTHERN ADIRONDACKS AND UPPER 80S MID HUDSON VALLEY AND NW
CT. LOCALLY HEAVY RAIN BOTH SUNDAY AND MONDAY COULD RESULT IN
LOCALIZED FLASH FLOODING AND A WATCH COULD BE CONSIDERED OVERNIGHT
OR TOMORROW DEPENDING ON HOW MUCH COVERAGE OF SHOWERS AND
THUNDERSTORMS COULD BE EXPECTED...SO STAY TUNED.
THERE ARE INDICATIONS THAT THE UPPER ENERGY AND WEAK COLD FRONT
EXIT THE REGION MONDAY NIGHT...WITH SOME POTENTIAL PARTIAL
CLEARING OUTSIDE OF AREAS OF FOG BY EARLY TUESDAY MORNING. LOWS
SHOULD BE IN THE 60S...WITH MAYBE SOME MID TO UPPER 50S IN THE
SOUTHERN ADIRONDACKS. ON TUESDAY...SOME WEAK UPPER RIDGING SHOULD
BE OVER THE REGION...BUT THE ATMOSPHERE SHOULD STILL BE UNSTABLE...
EVEN WITH NO REAL ORGANIZED LOW LEVEL FOCUS. SO...THERE COULD BE
ISOLATED SHOWERS AND THUNDERSTORMS IN THE SOUTHERN HALF OF THE
FORECAST AREA WITH HIGHS IN THE 80S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE PERIOD STARTS OUT LATE TUESDAY NIGHT INTO WEDNESDAY WITH A WARM
FRONT AND/OR PRE-FRONTAL TROUGH APPROACHING THE AREA FROM THE GREAT
LAKES AND OHIO VALLEY. THIS SYSTEM WILL BRING ADDITIONAL CHANCES FOR
AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS. THE EVENTUAL INTENSITY
OF T-STORMS WILL DEPEND ON THE DEGREE OF INSTABILITY...WHICH WILL BE
TIED TO CLOUD COVER. THERE SHOULD BE DECENT FLOW ALOFT FOR MID JULY
WITH A MIGRATORY SUB-1000MB CYCLONE TRACKING EASTWARD NEAR HUDSON
BAY.
THE FIRST SERIES OF FRONTAL BOUNDARY WILL PASS THROUGH BY SOMETIME
LATE WEDNESDAY OR WEDNESDAY NIGHT...WHILE THE MAIN COLD FRONT IS
FORECAST TO SAG SOUTHWARD ACROSS THE AREA LATE WEDNESDAY NIGHT INTO
THURSDAY. WILL CONTINUE TO MENTION CHANCE POPS DURING THIS
TIME...WITH THE POSSIBLY MORE ROBUST CONVECTION OCCURRING ON
WEDNESDAY. THERE COULD BE AN ADDITIONAL ROUND OF T-STORMS SOUTH OF
ALBANY ON THURSDAY IF THE FRONT SLOWS ENOUGH...WHICH IS BEING
DEPICTED BY THE 12Z GFS AND ECMWF.
IT AT LEAST LOOKS LIKE TEMPERATURES AND HUMIDITY LEVELS WILL START
TO SOMEWHAT DROP BY WEEK`S END AS A COOLER NORTHERLY FLOW DEVELOPS
IN WAKE OF THE COLD FRONT. HOWEVER...THE CHAOTIC UPPER LEVEL PATTERN
MAY ALLOW FOR A CUT-OFF LOW TO FORM SOMEWHAT IN THE VICINITY OF THE
OHIO VALLEY...MID ATLANTIC...OR SOUTHERN APPALACHIANS REGION WHICH
COULD RESULT IN A MOIST SOUTHERLY FLOW QUICKLY RETURNING BY THE
WEEKEND ALONG WITH RENEWED CHANCES FOR PRECIP AND INCREASING
HUMIDITY.
THERE STILL CONSIDERABLE UNCERTAINTY IN HOW THE PATTERN WILL
EVENTUALLY UNFOLD...BUT BOTH THE GFS AND ECMWF ARE DEPICTING A
CUT-OFF LOW FORMING SOUTH AND WEST OF OUR AREA NEXT WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
ANTICIPATING MAINLY VFR CONDITIONS THROUGH THE FORECAST PERIOD.
SOME SHRA /NO TSRA OBSERVED YET/ ACTIVITY TRACKING ALONG NY/PA
BORDER NEAR AND SOUTH OF BGM. DONT EXPECT THIS TO SURVIVE TO KPOU.
NOT CLEAR IF THE USUAL TROUBLE SPOTS OF KPSF AND KGFL WILL SLIDE
INTO IFR CONDITIONS OVERNIGHT. DRIER AIR IN EVIDENCE AT THOSE
TERMINALS TODAY WITH DEW POINTS INTO MID 60S. FOR NOW...WILL
CONTINUE WITH IDEA OF MVFR BR THERE. AT KPOU AND KALB...VFR
CONDITIONS.
TOMORROW...HAVE INCLUDED /VCSH/ FOR THE AFTERNOON AT ALL TERMINAL
EX KPOU. BETTER ORGANIZED SYSTEM WILL BE MOVING ACROSS NORTHERN
PORTION OF THE REGION. TIMING...INTENSITY... DURATION...NOT CLEAR
AT THIS POINT. SO VCSH WILL SUFFICE. HAVE NOT INCLUDED VCSH AT
KPOU. AS NOTED...BETTER CHANCES TO THE NORTH. ALSO COULD SEE SOME
TSRA AT TERMINALS...BUT AGAIN LIKELIHOOD/TIMING NOT APPARENT
ENOUGH TO INCLUDE IN THE TAFS THIS FAR OUT.
OUTLOOK...
SUN NITE-TUE...MAINLY VFR. SCT MAINLY AFTERNOON AND EVENING
SHRA/TSRA. POSSIBLE LATE NIGHT AND/OR EARLY MORNING FOG/LOW
STRATUS WITH MVFR/IFR POSSIBLE.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
FUELS CONTINUE TO REMAIN SATURATED FROM RECENT SHOWER/THUNDERSTORM
ACTIVITY. THERE WILL CONTINUE TO BE A CHANCE FOR AFTERNOON/EVENING
SHOWERS AND THUNDERSTORMS FOR THE NEXT SEVERAL DAYS AS THE BERMUDA
HIGH KEEPS A HOT AND HUMID AIR MASS ENTRENCHED OVER THE REGION.
NORMAL RH RECOVERIES EACH NIGHT BETWEEN 80 TO 100 PERCENT WILL ALLOW
FOR WIDESPREAD DEW FORMATION. DAYTIME RH VALUES WILL GENERALLY BE IN
THE 40 TO 60 PERCENT RANGE.
&&
.HYDROLOGY...
THE MOHAWK RIVER AT UTICA CONTINUES TO EXPERIENCE MINOR FLOODING.
THE RIVER AND CREEK FLOWS NEAR THE WEST CENTRAL MOHAWK RIVER ARE
EXPECTED TO GRADUALLY RECEDE INTO THE WEEKEND...UNLESS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS OCCUR OVER OR NEAR THE BASIN.
THERE COULD BE SCATTERED SHOWERS AND THUNDERSTORMS SUNDAY
AFTERNOON AND EVEN MORE COVERAGE OF SHOWERS AND THUNDERSTORMS
MONDAY AFTERNOON AND EVENING WITH THE APPROACH OF A WEAK COLD
FRONT. A MOIST AND HUMID AIR MASS WILL ALLOW ANY SHOWER OR
THUNDERSTORM TO BE CAPABLE OF PRODUCING LOCALLY HEAVY
DOWNPOURS...AND A QUICK INCH OR MORE OF RAINFALL DUE TO THE
ANOMALOUS PRECIPITABLE WATER VALUES.
THERE WILL BE A CONTINUED THREAT FOR ISOLATED FLASH FLOODING...AS
WELL AS FLOODING OF POOR DRAINAGE AND LOW LYING AREAS. NO FLASH
FLOOD WATCHES ARE BEING ISSUED DUE TO THE EXPECTED ISOLATED NATURE
OF ANY FLOODING. IT IS ALSO DIFFICULT TO DETERMINE WHERE THE
HEAVIEST RAINFALL WILL OCCUR.
WHILE ADDITIONAL FLOODING IS NOT ANTICIPATED ON ANY MAIN STEM RIVER
POINTS...LOCALLY SHARP RISES ARE POSSIBLE DUE TO ANY CONVECTION THAT
MAY OCCUR OVER THE NEXT SEVERAL DAYS...ESPECIALLY FOR THOSE POINTS
THAT ARE MORE FLASHIER IN NATURE.
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...HWJIV
NEAR TERM...HWJIV/OKEEFE
SHORT TERM...NAS
LONG TERM...JPV
AVIATION...OKEEFE
FIRE WEATHER...NAS
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
439 AM EDT Sun Jul 7 2013
...UPDATED FOR LACK OF PREDAWN RAIN AND FOR AVIATION SECTION...
.NEAR TERM [Today]...
Showers and isold tstms assocd with meeting of Gulf and east coast
seabreezes across Ern most counties late Sat eve weakened after
midnight. HRRR overforecast predawn precipitation over Wrn waters
and adjacent coastlines. Updated overnight grids to reflect this.
The large scale longwave blocking pattern continues to deamplify.
This is highlighted by a ridge over Wrn half of Conus, and a lifting
trough over Cntrl and Ern states with base over TN Valley and upper
low spinning from Mid Ms Valley into OH Valley. Looking east, a
ridge extends from high in Wrn Atlc a few hundred miles east of
Carolina coast WSW down South Atlc seaboard. Looking southeast, TUTT
low spinning invcnty of Bahamas. At the surface, Sly flow around Wrn
Atlc Bermuda high will remain over SE region.
During the rest of today, expect further lifting of low which will
reach Srn Great Lakes around sundown. This will allow Atlc high to
nose Swwd and deep layer ridge to encroach further inland pushing
tropical plume responsible for recent heavy rains further west of
our area. It will also combine with Wwd movement of TUTT placing CWA
closer to its subsident side. By this eve, TUTT actually moves under
ridge shifitng it back a little ewd. Lifting trough will also help
flatten Wrn and Atlc ridges and allow them to begin to bridge under
trough. However surface ridge axis remains to our north so ample low
level moisture remains. All this translates to increasing and strong
upper subsidence and dry air overspreading from the Atlc Swwd and
Nwwd to across local area. This reflected in model soundings which
show sharp W-E increase in mid level dry air and in decreasing PWAT.
i.e. GFS at 00z Mon with 1.79 in and 1.35 inches at TLH and JAX
respectively.
Thus scenario shifting somewhat to a more typical summertime pattern
of diurnal sea breeze convection especially east of the Apalachicola
River and with a continued sharp E-W POP/cloud gradient as reflected
in CAM and other High Res models. Will go with 20-60% SE-NW POP
gradient. Increasing dry air aloft should decrease aerial coverage
and delay onset of any storms compared to previous days. Although
the concentrated bands of heavy, flooding rains are not expected and
the flood watch has expired, soils over the Florida Panhandle and
into Southeast Alabama remain quite moist, so any rainfall could
cause some localized flooding issues if rainfall rates are high
enough. CAM flood tool still shows up to 30% possibility. With more
sunshine expected than recent days, temps should rebound back to
near seasonal levels with highs in the mid-upper 80s west to low 90s
east.
&&
.SHORT TERM [Tonight Through Tuesday]...
The blocky pattern of the past week will completely break down
during this period as the Midwest upper low opens up and ejects
east across New England by Monday night. The Atlantic ridge will be
further weakened as it is undercut by the TUTT low, which will reach
far South FL on Tuesday. These transformations will finally cut off
the flow of deep layer tropical air into the region and allow the
dry air seen on water vapor imagery over the Atlantic to work its
way westward into the forecast area. At the surface, the subtropical
ridge axis will extend across the Southeast U.S. through the period.
The ridge axis will be north of the area through Monday and then
slip to near the Gulf Coast on Tuesday. However, because of the
influence of drier air aloft, rain chances will actually dip to
below normal levels for this time of year, a refreshing change from
the recent rains. Of course, the flip side of getting less rain is
that temps will rise closer to seasonal levels. Highs Monday will be
near normal in the lower 90s. On Tuesday, we will actually see
slightly above normal max temps in the mid 90s across many inland
locations.
&&
.LONG TERM [Tuesday Night through Saturday]...
A fairly typical summertime pattern is expected with daily diurnal
convection through the period. By mid-week, an upper level low is
expected to approach from the southeast which could enhance rain
chances a little bit. Towards the end of the week as ridging builds
over the Plains, we may temporarily transition to more of a
northwest flow pattern with a weak front approaching from the
northwest. Near seasonal temperatures are expected.
&&
.AVIATION [Through 12z Monday]...
Lower ceilings/vsbys remain possible with all sites except ECP
possibly experiencing IFR conditions thru 13Z. By mid morning
hours, more showers and thunderstorms could develop around north
Florida with precipitation chances spreading to all other terminals
by the afternoon. DHN and ECP will have the highest chances of
receiving precipitation. Brief MVFR CIGS/VSBYS possible in any heavy
rain. VFR conditions are expected 00z-08z then MVFR CIGS/VSBYS again
possible 08Z-12Z where residual moisture remains from today`s rains.
&&
.MARINE...
A surface ridge of high pressure will become reestablished north of
the area this week allowing winds and seas to return to typical
summertime levels. Winds will generally be out of the east or
southeast.
&&
.FIRE WEATHER...
Red Flag conditions are not expected in the foreseeable future.
&&
.HYDROLOGY...
The overall threat for significant flooding has largely ended. Most
rivers across our area are either nearing their crest or have
recently crested. The greatest impacts continue to be on the
Choctawhatchee River at Bruce-Ebro which will reach major flood
stage. The Sopchoppy River moved above moderate flood overnight but
should gradually fall through today. All other rivers where flooding
is expected should generally crest in minor flood stage.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 73 91 72 94 / 50 20 40 20 30
Panama City 86 75 89 74 91 / 60 20 40 20 20
Dothan 88 73 91 72 95 / 60 30 40 20 30
Albany 91 74 92 73 94 / 60 30 40 20 30
Valdosta 91 72 92 70 93 / 30 20 40 20 30
Cross City 92 70 93 69 94 / 20 20 30 20 30
Apalachicola 86 74 88 74 89 / 50 20 30 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term/Aviation/Fire Weather...Block
Long Term...DVD
Hydrology...Block/Wool
Rest of Discussion...Wool
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
250 AM EDT Sun Jul 7 2013
.NEAR TERM [Through Today]...
Showers and isold tstms assocd with meeting of Gulf and east coast
sea breezes across Ern most counties late Sat eve weakened after
midnight. HRRR shows rain south of Panama City Beach, but for
the most part, expect the bulk of this rain to remain just offshore
into this morning.
The large scale long wave blocking pattern continues to deamplify.
This is highlighted by a ridge over Wrn half of CONUS, and a lifting
trough over Cntrl and Ern states with base over TN Valley and upper
low spinning over Mid MS Valley. Looking east, a ridge extends Ewd
into Wrn Atlc with high east of NC coast with axis down Ern
seaboard. Looking southeast, TUTT low spinning in vcnty of the
Bahamas. At the surface, Sly flow around Wrn Atlc high will remain
over SE region.
During the rest of today, expect further lifting of low which will
reach Srn Great Lakes around sundown. This will allow Atlc high to
nose Swwd and deep layer ridge to encroach further inland and combine
with Wwd movement of TUTT placing CWA closer to its subsident side.
Lifting trough will also help flatten Wrn and Atlc ridges and allow
them to begin to bridge under trough. All this translates to
increasing and strong upper subsidence and dry air overspreading
from from the Atlc Swwd and Nwwd to across local area. This
reflected in model soundings which show sharp W-E increase in mid
level dry air and in decreasing PWAT. i.e. GFS at 00z Mon with 1.79
in and 1.35 inches at TLH and JAX respectively. However surface
ridge axis remains to our north so ample low level moisture remains.
Thus scenario shifting somewhat to a more typical summertime pattern
of diurnal sea breeze convection especially east of the Apalachicola
River and with a continued sharp E-W POP/cloud gradient as reflected
in CAM and other High Res models. Will go with 20-60% SE-NW POP
gradient. Increasing dry air aloft should decrease aerial coverage
and delay onset of any storms compared to previous days. Although
the concentrated bands of heavy, flooding rains are not expected and
the flood watch has expired, soils over the Florida Panhandle and
into Southeast Alabama remain quite moist, so any rainfall over the
next few days could cause some localized flooding issues if rainfall
rates are high enough. CAM flood tool still shows up to 30%
possibility. With more sunshine expected than recent days, temps
should rebound back to near seasonal levels with highs in the
mid-upper 80s west to low 90s east.
&&
.SHORT TERM [Tonight Through Tuesday]...
The blocky pattern of the past week will completely break down
during this period as the Midwest upper low opens up and ejects
east across New England by Monday night. The Atlantic ridge will be
further weakened as it is undercut by the TUTT low, which will reach
far South FL on Tuesday. These transformations will finally cut off
the flow of deep layer tropical air into the region and allow the
dry air seen on water vapor imagery over the Atlantic to work its
way westward into the forecast area. At the surface, the subtropical
ridge axis will extend across the Southeast U.S. through the period.
The ridge axis will be north of the area through Monday and then
slip to near the Gulf Coast on Tuesday. However, because of the
influence of drier air aloft, rain chances will actually dip to
below normal levels for this time of year, a refreshing change from
the recent rains. Of course, the flip side of getting less rain is
that temps will rise closer to seasonal levels. Highs Monday will be
near normal in the lower 90s. On Tuesday, we will actually see
slightly above normal max temps in the mid 90s across many inland
locations.
&&
.LONG TERM [Tuesday Night through Saturday]...
A fairly typical summertime pattern is expected with daily diurnal
convection through the period. By mid-week, an upper level low is
expected to approach from the southeast which could enhance rain
chances a little bit. Towards the end of the week as ridging builds
over the Plains, we may temporarily transition to more of a
northwest flow pattern with a weak front approaching from the
northwest. Near seasonal temperatures are expected.
&&
.AVIATION...
[Through 06z Monday] Lower ceilings are a possibility in the early
morning hours on Sunday, with all sites except ECP possibly
experiencing IFR conditions thru 13Z. By the late morning hours,
more showers and thunderstorms could develop around north Florida,
impacting ECP and TLH, with precipitation chances spreading to all
other terminals by the afternoon. DHN and ECP will have the
highest chances of receiving precipitation tomorrow, with IFR
conditions possible in any thunderstorms that develop. VFR
conditions are expected 00z-06z.
&&
.MARINE...
A surface ridge of high pressure will become reestablished north of
the area this week allowing winds and seas to return to typical
summertime levels. Winds will generally be out of the east or
southeast.
&&
.FIRE WEATHER...
Red Flag conditions are not expected in the foreseeable future.
&&
.HYDROLOGY...
Only light showers were noted overnight. The overall threat for
significant flooding has largely ended. Most rivers across our area
are either nearing their crest or have recently crested. The
greatest impacts continue to be on the Choctawhatchee River at
Bruce-Ebro which has reached major flood stage and will remain
above that level for several days. The latest crest forecast is
nearly a foot and a half above the previous forecast and should
occur on Monday. The Sopchoppy River moved above moderate flood
overnight but appears to have crested and should gradually fall
through today. All other rivers where flooding is expected should
generally crest in minor flood stage.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 73 91 72 94 / 50 20 40 20 30
Panama City 86 75 89 74 91 / 60 20 40 20 20
Dothan 88 73 91 72 95 / 60 30 40 20 30
Albany 91 74 92 73 94 / 60 30 40 20 30
Valdosta 91 72 92 70 93 / 30 20 40 20 30
Cross City 92 70 93 69 94 / 20 20 30 20 30
Apalachicola 86 74 88 74 89 / 50 20 30 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term/Aviation/Fire Weather...Block
Long Term...DVD
Hydrology...Block/Wool
Rest of Discussion...Wool
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
355 AM EDT SUN JUL 7 2013
.SHORT TERM /TODAY THROUGH MONDAY/...
WATER VAPOR LOOP CONTINUES TO SHOW DEEP MOISTURE BEING FUNNELED INTO
W GA FROM THE TROPICS. PWATS HAVE BUMPED BACK UP TO AROUND 2 INCHES
ACROSS NORTHERN GA ACCORDING TO THE 00Z FFC SOUNDING. MODELS SHOW
THIS HIGH MOISTURE AXIS REMAINING ACROSS THE CWFA THROUGH TONIGHT.
SOMEWHAT DRIER AIR HAS MOVED IN ACROSS THE EASTERN PORTION OF THE
CWFA.
UPPER LOW ACROSS THE OHIO VALLEY WILL SLOWLY EJECT INTO THE MIDDLE
ATLANTIC BY EARLY MONDAY MORNING. MEANWHILE...THE BERMUDA HIGH AT
THE SURFACE WILL BEGIN TO BUILD WESTWARD...ALSO HELPING SHIFT THE
TROPICAL PLUME WESTWARD. THIS SHOULD RESULT IN A DECREASE IN
PWATS/MOISTURE CONTENT DURING THE DAY ON MONDAY.
LATEST RUNS OF THE HRRR SHOW THE BEST CHANCE FOR POPS IS IN NW GA
THIS MORNING. THIS SEEMS REASONABLE AS PRECIP AXIS HAS NOT MOVED
MOST OF THE NIGHT. SCT/NMRS SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS THE REMAINDER OF THE CWFA THIS AFT/EVE BUT THEY SHOULD BE
MORE DIURNALLY DRIVEN.
FFG IS LESS THAN AN INCH AND A HALF ACROSS AREAS MOSTLY NORTH OF THE
FALL LINE. WILL NOT MAKE ANY CHANGES TO THE FLOOD WATCH FOR NOW.
NLISTEMAA
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
EXTENDED BEGINS WITH UPPER WAVE MOVING OFF THE NEW ENGLAND COAST
WHILE CLOSED LOW OVER THE BAHAMAS IS WORKING ITS WAY WEST...AND
BETWEEN THESE TWO THE ATLANTIC HIGH IS RIDGING INTO THE SOUTHEAST.
THE EXITING SYSTEM ACROSS NEW ENGLAND ALLOWS THE ASSOCIATED
SURFACE BOUNDARY/FRONT TO ELONGATE AND STRETCH ACROSS THE
SOUTHEAST. BEST PRECIP CHANCES WILL BE ACROSS NORTH GEORGIA.
ANOTHER LONGWAVE TROUGH PUSHES INTO SOUTHERN CANADA AND THE UPPER
MISSISSIPPI VALLEY BY MIDWEEK AND WITH CONTINUE SOUTHERLY FLOW
FROM THE ATLANTIC AND GULF...PRECIP CHANCES INCREASE AGAIN
WEDNESDAY AND ESPECIALLY INTO THURSDAY AS THE TROUGH DIGS INTO THE
OHIO VALLEY AND A SURFACE FRONT MOVES INTO THE TENNESSEE VALLEY.
REALLY REMARKABLE AGREEMENT BETWEEN THE GFS AND ECMWF THROUGH THIS
PERIOD...THOUGH THE ECMWF IS A TAD DEEPER WITH THE WAVE INTO THE
SOUTHEAST AND A LITTLE BIT MORE NEGATIVELY TILTED.
LATE IN THE WORK WEEK THIS TROUGH CONTINUES TO DIG AND DEEPEN INTO
THE GREAT LAKES...EVENTUALLY FORMING A CUTOFF LOW OVER THE UPPER
OHIO VALLEY. GFS A LITTLE FASTER WITH THIS TRANSITION BUT STILL
PRETTY SIMILAR IN OVERALL DEPICTION. TROUGH AXIS PROGGED TO BE
GENERALLY ACROSS THE MIDDLE OF THE STATE...THUS REDUCING PRECIP
CHANCES ACROSS NORTHWEST GEORGIA BUT KEEPING POPS IN SOUTHEAST
ZONES. THE LOW CONTINUES TO DEEPEN AND DIG TO THE SOUTHWEST...
RETROGRADING IN RESPONSE TO DEEPENING UPPER HIGH OVER THE DESERT
SOUTHWEST AND WESTERN PLAINS. BY THE END OF THE PERIOD THE CUTOFF
LOW IS SOMEWHERE EITHER IN THE TENNESSEE VALLEY OR SOUTHEAST...
WITH BOTH MODELS CONTINUING TO RETROGRADE IT TO THE WEST BEYOND
THE END OF THE PERIOD. SO IN GENERAL...IT LOOKS LIKE NEXT WEEK
COULD BE A REPEAT OF WHAT WE SAW THIS PAST WEEK WITH SIGNIFICANT
MOISTURE TRANSPORT OUT OF THE GULF. WILL WAIT AND SEE HOW THIS
PLAYS OUT.
TEMPS REMAIN AT OR BELOW NORMAL THROUGH THE PERIOD. IF WE HAVE TO
PUT UP WITH ALL THE RAIN AND POTENTIAL FLOODING...AT LEAST WE GET
COOLER TEMPS OUT OF IT. HOWEVER...THERE IS A LARGER CONCERN THAT
WITH THIS CONTINUED WET PATTERN WE COULD BE SETTING THE STAGE FOR
SOME REAL PROBLEMS IF WE GET A TROPICAL SYSTEM MOVING IN.
TDP
&&
.AVIATION...
06Z UPDATE...
TROPICAL MOISTURE PLUME CONTINUES ACROSS THE REGION. MODELS ARE
SUPPORTING IFR CIGS AT MANY OF THE AIRPORTS THROUGH EARLY SUNDAY
MORNING. THE 00Z NAM SOUNDINGS SUPPORT THIS. IN ADDITION...PATCHY
MVFR FOG WILL ALSO BE POSSIBLE. SKIES SHOULD REMAIN MCLDY THROUGH
THE DAY WITH CIGS BKN AROUND 035-040. SHRA/TSRA WILL DEVELOP
DURING PEAK HEATING. LOW CIGS ARE POSSIBLE AGAIN TOMORROW NIGHT.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE FOR WINDS. MEDIUM CONFIDENCE REMAINING ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 82 70 86 71 / 70 40 50 30
ATLANTA 81 70 84 72 / 70 40 50 30
BLAIRSVILLE 75 67 78 66 / 70 50 60 30
CARTERSVILLE 80 69 86 69 / 70 40 60 30
COLUMBUS 84 73 89 73 / 70 30 50 20
GAINESVILLE 79 68 83 71 / 70 50 60 30
MACON 86 73 88 72 / 70 30 50 20
ROME 80 70 86 70 / 70 50 60 30
PEACHTREE CITY 81 70 84 70 / 70 40 50 30
VIDALIA 89 72 90 73 / 50 20 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
BANKS...BARROW...BARTOW...CARROLL...CATOOSA...CHATTOOGA...
CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...DADE...DAWSON...
DEKALB...DOUGLAS...FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...
GORDON...GREENE...GWINNETT...HALL...HARALSON...HEARD...HENRY...
JACKSON...LUMPKIN...MADISON...MORGAN...MURRAY...NEWTON...NORTH
FULTON...OCONEE...OGLETHORPE...PAULDING...PICKENS...POLK...
ROCKDALE...SOUTH FULTON...TALIAFERRO...TOWNS...UNION...WALKER...
WALTON...WHITE...WHITFIELD...WILKES.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....TDP
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
229 AM MDT SUN JUL 7 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1251 PM MDT SAT JUL 6 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW H5 RIDGE STILL IN PLACE
ACROSS SOUTHERN PLAINS...WITH WESTERLY FLOW ACROSS THE NORTHERN
PLAINS. SURFACE TROUGH IS CURRENTLY IN PLACE ACROSS WESTERLY
NEBRASKA EXTENDING SOUTH ACROSS NW KS AND SE CO.
DESPITE LITTLE BEING APPARENT IN THE 500 MB HEIGHT FIELD BEYOND SOME
WEAK RIPPLES WV IMAGERY AND PV/VORT FIELDS CONTINUE TO INDICATE
VIGOROUS SHORTWAVE ACTIVITY ROTATING AROUND THE NORTHERN PART OF THE
RIDGE. ONE SUCH FEATURE IS PROGGED TO PASS OVER OUR CWA BY THIS
EVENING...WHICH SHOULD HELP INCREASE THUNDERSTORM CHANCES ACROSS THE
REGION. I COULDNT RULE OUT BETTER COVERAGE THAN THE LAST FEW NIGHTS
WITH SURFACE TROUGH POSSIBLY ACTING TO AID THUNDERSTORM INITIATION AS
SHORTWAVE PASSES THROUGH THE REGION. I STILL EXPECT ACTIVITY TO
INITIALLY START OVER HIGHER TERRAIN THIS AFTERNOON AND BEGIN TO
SPREAD EAST WITH SHORTWAVE. LATEST HRRR/RAP SUPPORT THIS ACTIVITY
INCREASING IN COVERAGE BY 00-03Z AS THIS INTERACTS WITH SHORTWAVE
TROUGH AXIS AND BETTER INSTABILITY ACROSS THE CENTRAL/EASTERN PART
OF CWA. THERE IS SOME LINGERING ELEVATED INSTABILITY
OVERNIGHT...HOWEVER LLJ IS EAST OF CWA ALONG WITH BEST ISOTROPIC
SUPPORT...SO BEYOND SOME LINGERING SHOWERS/T-STORMS WITH SHORTWAVE
LATE TONIGHT IN THE EAST WITH SHORTWAVE I THINK MOST OF THIS
ACTIVITY WILL BE TAPERING OFF FAIRLY QUICKLY AFTER SUNSET.
HODOGRAPHS/SHEER PROFILES ARE RELATIVELY WEAK AND WITH MARGINAL CAPE
I AM NOT SURE WE WOULD SEE MUCH OF A SEVERE HAIL RISK. INVERTED V
TYPE SOUNDINGS AND DCAPE VALUES IN THE 500-1500 J/KG RANGE RAISE
CONCERNS FOR SEVERE GUST POTENTIAL WITH ANY COLLAPSING UPDRAFTS...SO
THIS WILL NEED TO BE MONITORED.
WITH LITTLE CHANGING REGARDING LARGE SCALE PATTERN AND MODELS
INDICATING POSSIBLE EARLIER INITIATION SUN I KEPT MENTION OF
THUNDERSTORM CHANCES SUNDAY AFTERNOON...WITH ONLY MINOR ADJUSTMENTS
TO TIMING. HOT AIRMASS WILL STILL BE IN PLACE SUN...WITH EXPECTED
CLOUD COVER THE ONE LIMITING FACTOR. FEWER CLOUDS...AND WE SHOULD
AGAIN SEE HIGHS APPROACH 100F ACROSS THE ENTIRE AREA.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 227 AM MDT SUN JUL 7 2013
LONG RANGE MODEL FORECAST INDICATES RIDGE PATTERN INCREASING IN
AMPLITUDE OVER THE FOUR CORNERS REGION FOR WEDNESDAY AND CONTINUING
TO BE PRESENT THROUGHOUT THE ENTIRE EXTENDED PERIOD. 500 MB HEIGHTS
WILL CONTINUE TO INCREASE IN MAGNITUDE INTO NEXT
WEEKEND...INDICATING THE INCREASING STRENGTH OF THE UPPER LEVEL
HIGH. THE UPPER LEVEL JET STREAM LOOKS TO STAY WELL TO THE NORTH
THROUGHOUT THE ENTIRE PERIOD. A SURFACE LOW PRESSURE SYSTEM WILL
STAY IN PLACE OVER THE TRI STATE AREA THROUGHOUT THE PERIOD WITH
STRONG WARM AIR ADVECTION MOVING INTO THE HIGH PLAINS. TEMPERATURES
LOOK TO BE IN THE MID 90S FOR WEDNESDAY AND THURSDAY...INCREASING TO
THE UPPER 90S TO LOW 100S ACROSS THE REGION FOR THE WEEKEND. BEST
CHANCE FOR PRECIPITATION WILL BE WEDNESDAY EVENING AND OVERNIGHT AS
STRONG SURFACE CONVERGENCE WILL HELP WITH THUNDERSTORM ACTIVITY.
ISOLATED CHANCES FOR THUNDERSTORM ACTIVITY WILL BE PRESENT MOSTLY
FOR THE EASTERN COUNTIES IN THE CWA FOR THURSDAY AND INTO NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1100 PM MDT SAT JUL 6 2013
VFR EXPECTED AT KGLD AND KMCK THROUGH THE PERIOD. SFC TROUGH WITH
LGT/VRB WINDS TO LINGER NEAR BOTH TERMINALS THROUGH 15-17Z BEFORE
BECOMING EASTERLY THEN SOUTHEASTERLY AT 10KTS OR SO. AS HAS BEEN
THE CASE THE PAST FEW DAYS SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE DURING THE LATE AFTERNOON AND EVENING HOURS. PINPOINTING
WHETHER OR NOT THEY WILL DIRECTLY IMPACT EITHER TERMINAL RATHER
DIFFICULT AND FOR NOW NOT INCLUDE A MENTION IN EITHER TAF.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1101 PM MDT SAT JUL 6 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1251 PM MDT SAT JUL 6 2013
LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW H5 RIDGE STILL IN PLACE
ACROSS SOUTHERN PLAINS...WITH WESTERLY FLOW ACROSS THE NORTHERN
PLAINS. SURFACE TROUGH IS CURRENTLY IN PLACE ACROSS WESTERLY
NEBRASKA EXTENDING SOUTH ACROSS NW KS AND SE CO.
DESPITE LITTLE BEING APPARENT IN THE 500 MB HEIGHT FIELD BEYOND SOME
WEAK RIPPLES WV IMAGERY AND PV/VORT FIELDS CONTINUE TO INDICATE
VIGOROUS SHORTWAVE ACTIVITY ROTATING AROUND THE NORTHERN PART OF THE
RIDGE. ONE SUCH FEATURE IS PROGGED TO PASS OVER OUR CWA BY THIS
EVENING...WHICH SHOULD HELP INCREASE THUNDERSTORM CHANCES ACROSS THE
REGION. I COULDNT RULE OUT BETTER COVERAGE THAN THE LAST FEW NIGHTS
WITH SURFACE TROUGH POSSIBLY ACTING TO AID THUNDERSTORM INITIATION AS
SHORTWAVE PASSES THROUGH THE REGION. I STILL EXPECT ACTIVITY TO
INITIALLY START OVER HIGHER TERRAIN THIS AFTERNOON AND BEGIN TO
SPREAD EAST WITH SHORTWAVE. LATEST HRRR/RAP SUPPORT THIS ACTIVITY
INCREASING IN COVERAGE BY 00-03Z AS THIS INTERACTS WITH SHORTWAVE
TROUGH AXIS AND BETTER INSTABILITY ACROSS THE CENTRAL/EASTERN PART
OF CWA. THERE IS SOME LINGERING ELEVATED INSTABILITY
OVERNIGHT...HOWEVER LLJ IS EAST OF CWA ALONG WITH BEST ISOTROPIC
SUPPORT...SO BEYOND SOME LINGERING SHOWERS/T-STORMS WITH SHORTWAVE
LATE TONIGHT IN THE EAST WITH SHORTWAVE I THINK MOST OF THIS
ACTIVITY WILL BE TAPERING OFF FAIRLY QUICKLY AFTER SUNSET.
HODOGRAPHS/SHEER PROFILES ARE RELATIVELY WEAK AND WITH MARGINAL CAPE
I AM NOT SURE WE WOULD SEE MUCH OF A SEVERE HAIL RISK. INVERTED V
TYPE SOUNDINGS AND DCAPE VALUES IN THE 500-1500 J/KG RANGE RAISE
CONCERNS FOR SEVERE GUST POTENTIAL WITH ANY COLLAPSING UPDRAFTS...SO
THIS WILL NEED TO BE MONITORED.
WITH LITTLE CHANGING REGARDING LARGE SCALE PATTERN AND MODELS
INDICATING POSSIBLE EARLIER INITIATION SUN I KEPT MENTION OF
THUNDERSTORM CHANCES SUNDAY AFTERNOON...WITH ONLY MINOR ADJUSTMENTS
TO TIMING. HOT AIRMASS WILL STILL BE IN PLACE SUN...WITH EXPECTED
CLOUD COVER THE ONE LIMITING FACTOR. FEWER CLOUDS...AND WE SHOULD
AGAIN SEE HIGHS APPROACH 100F ACROSS THE ENTIRE AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 1255 PM MDT SAT JUL 6 2013
AN UPPER RIDGE CENTERED OVER THE CENTRAL AND SOUTHERN ROCKIES WILL
BE THE DOMINATING INFLUENCE IN THE LONG TERM PERIOD. TEMPERATURES
WILL BE ABOVE NORMAL THE ENTIRE PERIOD...WITH THE HOTTEST DAYS
BEING FRIDAY AND SATURDAY. A WEAK COLD FRONT WILL MOVE THROUGH
TUESDAY AND TUESDAY NIGHT WITH SLIGHTLY COOLER TEMPERATURES IN ITS
WAKE. THERE WILL BE SEVERAL OPPORTUNITIES FOR SCATTERED
THUNDERSTORMS ASSOCIATED WITH WEAK SHORTWAVE TROUGHS ROTATING
AROUND THE RIDGE...BUT WITH THE WEAK FLOW ALOFT SEVERE WEATHER IS
NOT ANTICIPATED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1100 PM MDT SAT JUL 6 2013
VFR EXPECTED AT KGLD AND KMCK THROUGH THE PERIOD. SFC TROUGH WITH
LGT/VRB WINDS TO LINGER NEAR BOTH TERMINALS THROUGH 15-17Z BEFORE
BECOMING EASTERLY THEN SOUTHEASTERLY AT 10KTS OR SO. AS HAS BEEN
THE CASE THE PAST FEW DAYS SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE DURING THE LATE AFTERNOON AND EVENING HOURS. PINPOINTING
WHETHER OR NOT THEY WILL DIRECTLY IMPACT EITHER TERMINAL RATHER
DIFFICULT AND FOR NOW NOT INCLUDE A MENTION IN EITHER TAF.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
507 AM EDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT SUN JUL 7 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA WITH A CUTOFF MID/UPPER LEVEL LOW TO
THE SOUTH OVER IL/IN. A SHORTWAVE TROUGH COMBINED WITH UPPER LEVEL
DIV WITH THE RIGH ENTRANCE OF A 75 KNOT 250 JET OVER NRN ONTARIO...AND
FAVORABLE 925-700 THETA/E ADVECTION FROM THE UPPER MS VALLEY
SUPPORTED AN AREA OF SHRA/TSRA OVER LAKE SUPERIOR INTO W UPPER MI
AND NW WI WITH THE STRONGEST CONVECTION ON THE WRN END OF THE PCPN
AREA. AT THE SFC...A COLD FRONT HAD GRADUALLY SAGGED TO THE SOUTH INTO
NRN UPPER MI.
TODAY...EXPECT THAT WEAKENING SHRA/TSRA WILL CONTINUE TO SPREAD THROUGH
WRN INTO N CNTRL UPPER MI EARLY...PER RADAR AND SHORT RANGE MODEL
TRENDS...BEFORE THE FORCING ASSOCIATED WITH THE SHRTWV AND LOW LEVEL
INFLOW WEAKENS. BY LATE MORNING INTO THE EARLY AFTERNOON...THERE MAY
BE A LULL IN ANY PCPN BEFORE ADDITIONAL SCT SHRA/TSRA ALONG THE
FRONTAL BOUNDARY REINFORCED BY LAKE SUPERIOR BREEZE. THERE MAY BE
ENOUGH THINNING OR BREAKS IN THE CLOUD COVER FOR TEMPS TO RECOVER TO
NEAR 80...PUSHING MLCAPE VALUES INTO THE 1000-1500 J/KG RANGE.
HOWEVER...0-6KM SHEAR VALUES TO NEAR 30 KT WILL REMAIN MARGINAL FOR
STRONGER OR SEVERE ORGANIZED CONVECTION. THERE MAY STILL BE BRIEF HEAVY
RAIN AND GUSTY WINDS WITH TSRA THAT DEVELOP.
TONIGHT...AS DAYTIME HEATING SUBSIDES AND THE FRONT CONTINUES TO
PUSH TO THE SOUTH...THE REMAINING PCPN SHOULD SHIFT TO THE SOUTH AND
EAST AND DIMINISH. WITH LINGERING LOW LEVEL MOISTURE AND MID LEVEL
DRYING...AREAS OF FOG ARE EXPECTED TO DEVELOP. THERE COULD ALSO BE
SOME DRIZZLE NEAR THE WRN SHORE AS WEAK LOW LEVEL CONV DEVELOPS WITH
MOIST NE FLOW OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 505 AM EDT SUN JUL 7 2013
THE SURFACE FRONT WILL BE SOUTH OF THE FORECAST AREA MONDAY
MORNING...WITH WEAK SURFACE RIDGING ACROSS LAKE SUPERIOR. THIS WILL
HELP TO OVERALL DRY THE ATMOSPHERE...HOWEVER IT WILL ALSO ALLOW FOR
WEAK UPSLOPE FLOW IN AREAS NEAR LAKE SUPERIOR. THE NAM AND EVEN THE
GFS SUGGEST A VERY SHALLOW SATURATED LAYER BELOW 1000 FT WHICH WOULD
IMPLY AT LEAST A CHANCE FOR LOW CLOUDS AND DRIZZLE NEAR LAKE
SUPERIOR MONDAY MORNING. HOWEVER...BY AFTERNOON ANY LOW
CLOUD/DRIZZLE SHOULD MIX OUT. WILL ALSO MAINTAIN THE SLIGHT CHANCE
POPS IN THE LAKE BREEZE AREAS OF WESTERN UPPER MICHIGAN AND NEAR
LAKE MICHIGAN. ALTHOUGH THE NWP SUGGESTS A FAIRLY DRY ATMOSPHERE
BEHIND THE FRONT AND BROAD SCALE SUBSIDENCE...THE 850MB FRONT
WILL STALL OUT OVER THE AREA AND INTERIOR INSTABILITY RISES TO
NEARLY 1500 J/KG. NOT TO CONFIDENT THAT ANY SHOWERS/STORMS WILL
OCCUR MONDAY AFTERNOON...BUT ALSO NOT CONFIDENT ENOUGH TO REMOVE THE
MENTION. REGARDLESS...MONDAY WILL BE COOLER AND A LITTLE LESS HUMID
THAN TODAY WITH READINGS NEAR LAKE SUPERIOR DROPPING BACK INTO THE
LOWER-MID 70S.
MONDAY NIGHT SHOULD BE A FAIRLY QUIET NIGHT ACROSS THE AREA AS THE
NEXT LOW PRESSURE SYSTEM DEVELOPS ACROSS THE PLAINS. THE MODELS HAVE
BACKED OFF ANY PCPN FOR THE AREA MONDAY NIGHT...INSTEAD FOCUSING IT
ACROSS MN WHERE THE BETTER LOW LEVEL MOISTURE TRANSPORT AND DEEP
MOISTURE WILL BE LOCATED.
SOME DISAGREEMENT REMAINS REGARDING TIMING OF PRECIPITATION ON
TUESDAY. THERE IS A HINT FROM THE ECMWF AND GFS THAT AN MCS WILL BE
ONGOING TO WEST OF THE AREA IN THE BROAD WARM ADVECTION/ISENTROPIC
LIFT AREA IN SRN MN. THIS LEADS TO MUCH UNCERTAINTY REGARDING
CONVECTIVE EVOLUTION TUE FOR THE AREA. THE MAIN FORCING MECHANISM
TUE AND TUE NIGHT WILL CONTINUE TO BE THE NRN STREAM ENERGY DIVING
OUT OF CANADA AND AMPLIFYING DURING THE DAY...AND HAVE OPTED TO
FOCUS ON THIS FEATURE SIMILAR TO THE NAM SOLUTION. WITH THE BEST
FORCING WITH ENERGY BEING LATE TUE AFTN AND EVENING...HAVE OPTED TO
MAINTAIN THE HIGHEST POPS DURING THIS PERIOD. DEPENDING ON THE
AMOUNT OF DEBRIS CLOUDS...MODEST INSTABILITY IS POSSIBLE ACROSS THE
AREA TUE AFTN/EVENING HELPING TO MAINTAIN THUNDERSTORM DEVELOPMENT
ALONG THE FRONT. CANNOT TOTALLY RULE OUT SOME ORGANIZATION TO THE
STORMS LATER TUESDAY INTO TUESDAY EVENING AS A COUPLED UPPER JET
STRUCTURE DEVELOPS ACROSS THE NRN LAKES IN RESPONSE TO THE WAVE
BECOMING NEGATIVELY TILTED.
THE FRONT MOVES THROUGH THE AREA BY WEDNEDAY MORNING. MAY BE SOME
RESIDUAL WRAP AROUND MOISTURE ACROSS THE AREA IN THE MORNING...BUT
OTHERWISE THE WEATHER SHOULD IMPROVE DURING THE DAY. MODELS IN
EXCELLENT AGREEMENT IN SHOWING BROAD HIGH PRESSURE ACROSS THE UPPER
GREAT LAKES FOR THE END OF THE WEEK WITH RISING HEIGHTS BY THE
WEEKEND. TEMPERATURES WILL BE SEASONABLE THU AND FRIDAY ALTHOUGH
ABOVE NORMAL TEMPS MAY RETURN BY SATURDAY WITH 850MB TEMPS PROGGED
TO RISE TO +16 ACROSS THE WEST. CANNOT RULE OUT SHOWERS SATURDAY
AFTERNOON AS BOTH THE GFS AND ECMWF HINT AS AN UPPER WAVE MOVING
THROUGH THE AREA IN THE WESTERLY FLOW. HOWEVER...AT THIS TIME WILL
OPT TO MAINTAIN A DRY FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 158 AM EDT SUN JUL 7 2013
LINE OF SHRA/TS NOW MOVING THRU WRN LK SUP WL IMPACT CMX/IWD EARLY
THIS MRNG...LOWERING CONDITIONS TO MVFR AT LEAST BRIEFLY AS RA
MOISTENED/LK COOLED AIR FOLLOWS INLAND. SAW SHOULD REMAIN DRY THRU
SUNRISE WITH VFR CONDITIONS. SCT SHRA/PERHAPS A TS LIMITED BY DRYING
ALF WL ARRIVE W-E ON SUN IN ADVANCE OF AN APRCHG COLD FNT. THE BEST
CHC FOR THE TS WL BE AT SAW IN THE AFTN...BUT CONFIDENCE IN TIMING
IS TOO LO TO INCLUDE IN THE TAF FOR NOW. SOME LO CLDS/MVFR CIGS ARE
LIKELY TO FOLLOW THE FROPA THIS EVNG WITH DIURNAL COOLING AND
UPSLOPE N-NW FLOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT SUN JUL 7 2013
GIVEN EARLY SHIP OBSERVATIONS OF ZERO VISIBILITY OVER WESTERN LAKE
SUPERIOR AND VERY HUMID AIRMASS OVER CHILLY WATER FOLLOWING SOME
SHOWERS...A DENSE FOG ADVISORY WILL REMAIN IN EFFECT THIS MORNING
FOR THE WEST HALF OF LAKE SUPERIOR. SOME DRYING ON SUNDAY
AFTERNOON FOLLOWING A COLD FRONTAL PASSAGE SHOULD DISSIPATE THE
THICKEST FOG.
WINDS WILL REMAIN BELOW 15 KT ACROSS LAKE SUPERIOR THROUGH TUESDAY
AS A WEAK SURFACE TROUGH DROPS SOUTHWARD ACROSS THE LAKE FOLLOWED BY
AN AREA OF HIGH PRESSURE. WITH SHOWERS AND THUNDERSTORMS EARLY TODAY
AND ADDITIONAL SCT SHRA/TSRA POSSIBLE THIS AFTERNOON...AREAS
OF FOG WILL CONTINUE ACROSS THE LAKE. AS ANOTHER LOW DEVELOPS OVER
THE PLAINS ON TUESDAY AND APPROACHES LAKE SUPERIOR ON
WEDNESDAY....NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL BE POSSIBLE
BEHIND FOR A TIME WEDNESDAY AND WEDNESDAY NIGHT. A SURFACE HIGH
MOVING OVER THE UPPER LAKES LATE IN THE WEEK WILL ALLOW LIGHT WINDS
TO RETURN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
416 AM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CDT SUN JUL 7 2013
A COUPLE OF WEAK BOUNDARIES OF CONCERN TO START THE DAY. ONE IS A
TROUGH/COLD FRONT THAT AT 3 AM WAS ALONG THE ND/MN DOWN TO A WEAK
LOW OVER NE SODAK...EXTENDING BACK SW INTO CENTRAL NEB. OTHER
BOUNDARY IS A STATIONARY FRONT EXTENDING FROM AROUND MORRIS ACROSS
CENTRAL MN INTO THE HAYWARD AREA. LLJ AND WAA REGIME NORTH OF THE
STATIONARY BOUNDARY HAS GENERATED A CLUSTER OF STORMS OVER LAKE
SUPERIOR THAT HAVE STAYED SAFELY AWAY FROM THE MPX AREA OVERNIGHT.
FOR TODAY...THIS STATIONARY BOUNDARY WILL START TO LOOSE ITS
DEFINITION AS IT SLOWLY SAGS SE. MOST DETERMINISTIC MODELS SAY TODAY
WILL BE DRY AS GRADUAL HEIGHT RISES OVERTAKE THE AREA.
HOWEVER...THE ZONAL FLOW OVER THE REGION TODAY LOOKS TO BE OF THE
DIRTY VARIETY...WITH THE RAP/GFS/NAM SHOWING SMALL PERTURBATIONS
CURRENTLY GENERATING STORMS OUT OVER MT/WY WORKING ACROSS MN DURING
THE LATE AFTERNOON/EARLY EVENING. 07.00 NAM SOUNDINGS SHOW A RATHER
UNSTABLE ENVIRONMENT BEING IN PLACE AS THESE WAVES APPROACH...WITH
2000-3000+ J/KG OF UNCAPPED SBCAPE BEING IN PLACE. AT THE SAME
TIME...RAP SOUNDINGS ONLY ABLE TO GENERATE 1500 J/KG AT BEST.
700-500 MB LAPSE RATES ARE MEAGER ON BOTH /ABOUT 6 DEG C PER
KM/...WITH THE DIFFERENCE COMING WITH HANDLING OF LOW LEVEL
MOISTURE...AS THE RAP LOOKS A LITTLE AGGRESSIVE ON MIXING OUT DEWPS
THIS AFTERNOON...WHICH IN TURN IS IMPACTING ITS INSTABILITY
FORECAST. NAM IDEA IS PROBABLY MORE REALISTIC...BUT GIVEN MID-LEVEL
LAPSE RATES...WOULD FAVOR 1500-2500 J/KG OF CAPE TO WORK WITH TODAY.
WITH ALL THAT SAID...AT THE MOMENT ONLY HAVE CHANCE POPS MENTIONED
IN THE FAR ERN CWA THIS AFTERNOON AS THIS IS WHERE SOME FORM OF LLJ
FORCING LOOKS TO RESIDE...BUT GIVEN THE INSTABILITY MENTIONED
ABOVE...COULD SEE STORMS DEVELOP ANYWHERE ALONG/SOUTH OF THE
STATIONARY BOUNDARY. 03Z HOPWRF ENSEMBLE REFLECTIVITY FORECASTS HINT
AT THIS HAPPENING...WITH SCATTERED CONVECTION SEEN AT 21Z ON MEMBERS
1/3/4 ACROSS MOST OF THE AREA. GUESS AT THIS POINT...THIS "WET
PATTERN" THAT SET IN FRIDAY NIGHT HAS NOT EXACTLY PRODUCED MUCH IN
THE WAY OF OBSERVABLE PRECIPITATION IN THE MPX AREA...SO AM A BIT
GUN SHY ON GOING TO HIGH WITH POPS AT THIS POINT. WITH LOW LEVEL
FLOW BACKING OFF CONSIDERABLY TODAY...LOW LEVEL SHEAR WILL BE PRETTY
WEAK TODAY...BUT WITH INVERTED V SOUNDINGS SEEN IN MODELS...A
CONDITIONAL WIND THREAT WOULD EXIST.
FOR TONIGHT...LLJ FORCING AND THICKNESS PATTERN CONTINUE TO SHOW THE
MPX AREA SPLIT BETWEEN BETTER REGIONS OF FORCING FOR CONVECTION OVER
NRN IL/SRN WI AND OUT WEST ACROSS THE DAKOTAS...SO EXPECT TONIGHT TO
BE DRY ONCE ANY DIURNALLY DRIVEN ACTIVITY DISSIPATES THIS EVENING.
FOR TEMPERATURES...DENSE MID LEVEL CLOUD COVER SHOULD CLEAR ERN
AREAS FAIRLY QUICKLY THIS MORNING...WITH A FAIR AMOUNT OF SUNSHINE
EXPECTED AS A RESULT. AIRMASS HAS CHANGED VERY LITTLE SINCE
YESTERDAY...SO EXPECT HIGHS TO BE VERY SIMILAR TO WHAT WAS SEEN
OUTSIDE OF CENTRAL MINNESOTA ON SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 409 AM CDT SUN JUL 7 2013
MAIN CHALLENGE IS TRYING TO PINPOINT THE TIMING AND PLACEMENT OF
POPS EARLY IN THE WEEK BEFORE WE DRY OUT WEDNESDAY THROUGH FRIDAY.
THE UPPER LEVEL RIDGE ANCHORED OVER THE DESERT SOUTHWEST WILL
REMAIN THROUGHOUT THE PERIOD. MONDAY SHOULD START OUT DRY AS THE
LOW LEVEL JET AS SEEN IN THE H925 WINDS AND MOISTURE TRANSPORT
WILL REMAIN WELL SOUTH OF THE FORECAST AREA IN SOUTHERN
IOWA/ILLINOIS. THE HUMID AIRMASS WILL PERSIST ACROSS THE UPPER
MIDWEST...AND WITH LITTLE MIXING EXPECTED ON MONDAY HAVE INCREASED
DEWPOINTS INTO THE LOW 70S. BY MONDAY EVENING FORECAST MODELS
INDICATE A SUBTLE H500 SHORTWAVE ROTATING AROUND THE PERIPHERY OF
THE AFOREMENTIONED MONSOON RIDGE AND THIS SHOULD TRIGGER OFF SOME
DEEP CONVECTION ON THE LEE SIDE OF THE ROCKIES WHICH WILL ADVECT
EASTWARD OVER THE HIGH PLAINS OF THE DAKOTAS...AND COULD REACH THE
CWA LATER MONDAY NIGHT INTO EARLY TUESDAY MORNING. THE 07.12 GFS
AND ECMWF PLACE THE NOSE OF THE LOW LEVEL JET IN A FAVORABLE
LOCATION FOR CONVECTION OVER THE MISSISSIPPI RIVER VALLEY.
CURRENTLY HAVE THE HIGHEST POPS ALONG I90 NEAR THE IA BORDER...BUT
THESE MAY NEED TO BE ADJUSTED NORTHWARD IF THE MODELS FOLLOW THE
LEAD OF THE ECMWF...WHICH TAKES THE MCS ALONG AND NORTH OF I94.
THERE WILL BE PLENTY OF INSTABILITY AS SREF PLUMES KEEP AROUND
1000 J/KG OF MUCAPE ACROSS THE REGION MONDAY NIGHT...WITH ROUGHLY
30KTS OF DEEP LAYER SHEAR DEPENDING ON THE PLACEMENT OF THE LLJ.
THE FORECAST FOR TUESDAY BECOMES DIFFICULT SINCE MANY OF THE DETAILS
HINGES DIRECTLY ON THE MESOSCALE FEATURES LEFT IN THE WAKE OF THE
EARLY MORNING CONVECTION. A MORE WELL-DEFINED SHORTWAVE CURRENTLY
OFF THE MOVING DOWN THE COAST OF BRITISH COLUMBIA WILL TRANSLATE
EASTWARD IN THE ZONAL FLOW ALONG THE INTERNATIONAL BORDER AND ARRIVE
ACROSS THE UPPER MIDWEST TUESDAY AFTERNOON. THIS WILL DRIVE A COLD
FRONT THROUGH THE REGION ON TUESDAY...HOWEVER EXPECT ANY REMNANT
DEBRIS CLOUDS TO CLEAR OFF ALLOWING THE BOUNDARY LAYER TO RECOVER
DURING THE LATE MORNING HOURS...WITH AN UNSTABLE ENVIRONMENT SETTING
UP ACROSS THE MN/WI BORDER BY TUESDAY AFTERNOON. AN H500 SPEED MAX
OF 60KTS...ALONG WITH 3M/HR HEIGHT FALLS WILL PROVIDE SYNOPTIC SCALE
FORCING FOR SEVERE THUNDERSTORMS AHEAD OF THE COLD FRONT. AS ALLUDED
TO IN THE SPC DAY3 OUTLOOK...ANY OUTFLOW BOUNDARY PRODUCED BY THE
EARLY MORNING CONVECTION WILL BE THE FOCUS FOR AN ENHANCED THREAT OF
SEVERE WEATHER...INCLUDING TORNADOES AS THE SURFACE WINDS BACK AHEAD
OF THE COLD FRONT. NAM BUFR SOUNDINGS FOR TUESDAY AFTERNOON AT KRWF
SHOW A CYCLONICALLY CURVED HODOGRAPH WITH 0-3KM HELICITY OF OVER
300M2/S2. THE GFS IS FASTER WITH THE COLD FRONT...SO ITS LINEAR
SHEAR PROFILE WITH NORTHWEST WIND IS LESS FAVORABLE FOR
TORNADOES...BUT RATHER WOULD SUPPORT STRAIGHT LINE WINDS.
REGARDLESS...TUESDAY SEVERE THREAT LOOKS TO BE THE MAIN CONCERN
DURING THE EXTENDED.
NORTHWEST FLOW IN THE WAKE OF THIS COLD FRONT WILL USHER IN DRIER
AIR AS A CANADIAN HIGH PRESSURE BUILDS ON WEDNESDAY AND KEEPS THE
REGION DRY THROUGH FRIDAY. HAVE INCREASED WINDS SLIGHTLY ABOVE
GUIDANCE ON WEDNESDAY AS FORECAST SOUNDINGS SHOW ANOTHER GOOD MIXING
DAY. LOOKING AHEAD...THE REPRIEVE FROM THE HEAT AND HUMIDITY WILL BE
SHORTLIVED AS THE THERMAL RIDGE DEVELOPS BY THE END OF THE WORK WEEK
ACROSS THE HIGH PLAINS. WILL ACTUALLY SEE A WEST/EAST TEMPERATURE
GRADIENT BY THE WEEKEND...WITH MUCH WARMER TEMPERATURES ACROSS
WESTERN MINNESOTA. CURRENTLY HAVE MORE OF A BLENDED APPROACH WHICH
YIELDS ONLY MID 80S ACROSS THE WEST. THERE IS STILL
UNCERTAINTY...BUT IF THE H850 TEMPS REMAIN 20-22C WILL LIKELY SEE
HIGHS IN THE MID 90S NEAR THE MN/SD BORDER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1247 AM CDT SUN JUL 7 2013
THUNDER THIS EVENING OVER LAKE SUPERIOR SITTING ON THE NOSE OF THE
LLJ...AND EXPECT IT TO REMAIN IN THAT DIRECTION...SO HAVE REMOVED
ANY MENTION OF PRECIP FROM TAFS. INSTEAD...CONCERN FOR TAFS IS THE
POTENTIAL FOR FOG ACROSS WRN/CENTRAL MN AS MID LEVEL CLOUDS SLOWLY
CLEAR OUT. UNDER THESE CLEAR SKIES...LIGHT WINDS WITH DEWPS IN THE
UPPER 60S/LOWER 70S HAS ALREADY ALLOWED FAIRLY EXPANSIVE BR/FG TO
DEVELOP FROM NRN BACK THRU WRN MN. ADDED SOME IFR VIS FOR
AXN/STC...BUT THEY COULD END UP MUCH WORSE THAN THAT. FOR THE
AFTERNOON...MODELS ARE NOT ALL THAT EXCITED ABOUT STORMS...BUT THE
NAM/GFS SHOW A SHORT WAVE CURRENTLY OUT OVER WYOMING CROSSING MN
DURING PEAK HEATING...AS THE WEAK SFC BOUNDARY SITS FROM SRN/ERN
MN UP INTO NRN WI. THIS MAY ALLOW FOR ISO/SCT TSRA DEVELOPMENT
LATE IN THE AFTERNOON FOR MSP/EAU/RNH. CONFIDENCE IN THIS
HAPPENING IS LOW AT THE MOMENT...BUT WILL GIVE ME SOMETHING TO
CHEW ON FOR THE 12Z TAFS. SUNDAY NIGHT WILL BE SIMILAR TO TONIGHT
WITH LIGHT WINDS AND HIGH DEWPS...SO MAY HAVE TO BRING BACK SOME
BR INTO THE TAFS AGAIN.
KMSP...CONFIDENCE HIGH IN THE REST OF THE NIGHT BEING DRY AND VFR
WITH S WINDS SLOWLY VEERING AS THEY SLACKEN OFF. THERE IS THE
POTENTIAL FOR A STRAY THUNDERSTORM IN THE AREA SUN EVENING...MAINLY
BETWEEN 22Z AND 02Z...BUT CONFIDENCE IN THEIR OCCURRENCE NOT HIGH
ENOUGH TO INCLUDE IN THE TAF. BY MONDAY MORNING...WITH LIGHT WINDS
AND HIGH DEWPS...MAY SEE VIS IN HZ/BR MAKE A RUN FOR 4 OR 5 SM
MONDAY MORNING.
/OUTLOOK FOR KMSP/
MON...MVFR VIS POSSIBLE EARLY. CHC TSRA LATE NIGHT. WINDS E 5 KTS.
TUE...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE BCMG NW AT 5 KTS.
WED...VFR. WINDS NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
332 AM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT SUN JUL 7 2013
IF MOISTURE CAN REMAIN IN PLACE THIS MORNING THEN ANOTHER ROUND OF
THUNDERSTORMS COULD DEVELOP THIS AFTERNOON AND TONIGHT. THE
DISTURBANCE AND ONGOING STORM ACTIVITY ACROSS WESTERN NEB SHOULD
EXIT THE FCST AREA TO EAST BY 20Z. THIS IMPLIES THAT THE STORMS
WEAKEN AND FALL APART AS THEY MOVE EAST AS INDICATED BY THE HRRR.
DEEP EASTERLIES SHOULD CONTINUE TODAY AS INDICATED BY THE VWP AT
KUDX AND THIS WOULD SUPPORT DESTABILIZATION ACROSS WESTERN NEB LATE
THIS MORNING THROUGH THIS EVENING WHICH IN TURN WOULD PROPAGATE EAST
THROUGH THE FCST AREA. THE FCST MIGHT BE AMBITIOUS WITH THE 40 POPS
BUT THIS IS A MARK DOWN FROM A 5 MODEL BLEND OF THE
ECM...GFS...SREF...NAM AND GEMREG. WATER VAPOR SUGGESTS ANOTHER
DISTURBANCE ACROSS WRN WY AND NRN UT WHICH COULD COME ACROSS THIS
AFTERNOON ON THE HEALS OF THE ONGOING DISTURBANCE.
MODEST DEEP LAYER SHEAR UP TO 250 MB WOULD PERHAPS SUPPORT ISOLATED
SEVERE STORMS WHICH WOULD PROBABLY PULSE SEVERE FROM TIME TO TIME
THIS AFTERNOON AND THIS EVENING. THE WEAKNESS IN THE LOW LEVEL WINDS
SUGGESTS THIS BEHAVIOR. SPC SUGGESTED A WEAKLY ORGANIZED MCS MIGHT
DEVELOP AND THIS CERTAINLY APPEARS IN LINE WITH THE 21Z OUTPUT OF
THE 06Z HRRR SHOWING A FAIRLY ORGANIZED LINE OF STORMS FROM KOGA TO
KVTN.
HIGHS IN THE UPPER 80S TO MID 90S ARE EXPECTED TODAY. THE MODELS
HAVE COME IN A FEW DEGREES COOLER FOR HIGHS TODAY VERSUS SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 311 AM CDT SUN JUL 7 2013
ACTIVE FIRST HALF OF THE WEEK EXPECTED...AS THE AREA REMAINS ON
THE NORTHERN SIDE OF LARGE RIDGE OF UPPER HIGH PRESSURE CENTERED
ACROSS THE FOUR CORNERS REGION. WINDS ALOFT...MOISTURE...AND
INSTABILITY WILL BE FAVORABLE FOR TSTMS UNTIL THE RIDGE BEGINS TO
BUILD NORTH OVER THE AREA BY WEEKS END. TEMPERATURES ALOFT WILL
WARM THEN AS WELL AS A DECREASE IN WINDS ALOFT...CONDITIONS LESS
FAVORABLE FOR TSTM DEVELOPMENT.
A STATIONARY FRONT WILL OSCILLATE NORTH AND SOUTH THE FIRST HALF
OF THE WEEK...AND WILL BE A FOCUS FOR STORM DEVELOPMENT. OTHER
STORMS MAY FORM OFF THE HIGHER TERRAIN TO OUR WEST AND MOVE EAST
INTO THE AREA DURING THE EVENING HOURS. PWATS WILL BE RATHER
HIGH...WITH PLENTY OF LOW LEVEL MOISTURE IN PLACE TOO...SO SOME
DECENT RAINFALL TOTALS ARE POSSIBLE.
TEMPERATURES WILL BE WARM...AND THEN TURNING HOT BY WEEKS END AS
THE RIDGE BUILDS NORTH OVER THE AREA. HIGHS IN THE UPPER 80S TO
MID 90S WILL START THE WEEK...WITH MID 90S TO AROUND 100 TO FINISH
THE WEEK. DEPENDING ON DEW POINTS...WHICH CURRENTLY LOOK TO REMAIN
HIGH EAST OF HIGHWAY 83 AS THE HEAT BUILDS IN BY THE END OF THE
WEEK...WE COULD BE FLIRTING WITH HEAT ADVISORY CONDITIONS. WILL
CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1226 AM CDT SUN JUL 7 2013
CLUSTER OF TSRA MOVING INTO PORTIONS OF NORTH CENTRAL NEBRASKA
CONTINUE TO MOVE EAST AND SEEM TO BE MAINTAINING STRENGTH...UNLIKE
TSRA EARLIER IN THE EVENING AS THEY ENCOUNTERED LESS FAVORABLE MID
LEVEL INSTABILITY. INSTABILITY MAY BE SLIGHTLY BETTER NOW BASED ON
MESOANALYSIS OF MID LEVEL LAPSE RATES. AT THIS TIME HAVE MENTIONED
VCTS FOR KVTN AFTER 08Z ASSUMING THEY HOLD TOGETHER.
OTHERWISE VFR CONDITIONS FOR THE PERIOD...HOWEVER TSRA CHANCES
INCREASE AGAIN SUNDAY AFTER ABOUT 20Z WITH A BOUNDARY IN PLACE
ACROSS THE SOUTHERN PORTION OF THE FCST AREA. INCREASING LOW LEVEL
MOISTURE NORTH OF THE BOUNDARY LEADING TO A BETTER SHEAR/CAPE
BALANCE SHOULD ALLOW BETTER COVERAGE OF STORMS TO AFFECT TAF SITES
DURING THE FAVORED DIURNAL PERIOD FOR TSRA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...JWS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1145 PM CDT SAT JUL 6 2013
.DISCUSSION...
PROBABLY NOT MUCH OF A CHANCE OF ANY PRECIPITATION OVERNIGHT AS
WHATEVER REMAINS OF A WEAK UPPER LEVEL DISTURBANCE THAT WAS MOVING
THROUGH CENTRAL NEBRASKA CONTINUES TO WASH OUT OVERNIGHT AS THE
SURFACE FRONT REMAINS TO OUR WEST.
&&
.AVIATION...06Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS
THROUGH THE PERIOD WITH SOUTHEAST WINDS LESS THAN 10 KNOTS
GENERALLY...WITH WINDS BECOMING SOUTHWEST BY 15Z. A FRONTAL
BOUNDARY WILL BE MOVING INTO THE AREA SUNDAY MORNING...WHICH
SHOULD BRING A SURFACE WIND SHIFT TO THE NORTHEAST AT KOFK BY 15Z.
DEWALD
PREV DISCUSSION... /ISSUED 331 PM CDT SAT JUL 6 2013/
DISCUSSION...
OFF-AND-ON THUNDERSTORM CHANCES OVER THE NEXT SEVERAL DAYS ARE THE
MAIN FORECAST CONCERNS.
MORNING UPPER AIR CHARTS SHOWED HIGH PRESSURE IN THE SOUTHWEST
STATES AND OFF THE ATLANTIC COAST WITH A WEAK LOW IN THE MIDDLE
MOVING INTO THE OHIO VALLEY REGION. FAST WESTERLY FLOW COVERED THE
NORTHERN TIER OF THE CONUS. OUR AREA REMAINED IN THE TRANSITION ZONE
OF HIGHER HEIGHTS TO THE SOUTH AND FAST FLOW TO THE NORTH. AT THE
SURFACE...A WIND SHIFT LINE WAS NOTED IN CENTRAL SOUTH DAKOTA AND
WESTERN NEBRASKA...TIED TO A SHORTWAVE EXTENDING FROM THE NORTHERN
PLAINS INTO NEBRASKA. AND A COLD FRONT WAS PUSHING INTO THE WESTERN
DAKOTAS.
LIGHT SHOWERS OR SPRINKLES THAT MOVED ACROSS EASTERN NEBRASKA THIS
MORNING HAVE LEFT OUR AREA CAPPED TO CONVECTION SO FAR THIS
AFTERNOON. RAP SOUNDINGS SUGGEST SURFACE-BASED CAPES WERE TOPPING
1000 J/KG...BUT INHIBITION WAS STILL ROBUST. BUT WITH TEMPERATURES
WARMING A FEW MORE DEGREES LATE IN THE DAY...COULD SEE AN ISOLATED
SHOWER OR STORM POP UP THIS EVENING...PROBABLY IN WESTERN IOWA. THEN
LATER TONIGHT...WIND SHIFT LINE WILL SETTLE SOUTHEAST INTO OUR AREA
AS SHORTWAVE MOVES OFF TO THE EAST. INSTABILITY WAS STRONG IN
CENTRAL/WESTERN SOUTH DAKOTA NEAR/AHEAD OF WIND SHIFT...SO AM
EXPECTING STORMS TO FIRE THERE LATE THIS AFTERNOON OR EVENING. THIS
ACTIVITY SHOULD PUSH OFF TO THE EAST BUT COULD SKIRT OUR NORTHERN
CWA. OTHERWISE MORE GENERAL THUNDER CHANCES ARE POSSIBLE WITH WIND
SHIFT LINE AS IT MOVES INTO EASTERN NEBRASKA AFTER MIDNIGHT.
SURFACE BOUNDARY WILL REMAIN IN OUR AREA DURING THE DAY SUNDAY. NOT
MUCH NOTED IN MID LEVEL FLOW TO KICK UP CONVECTION ALONG THE
FRONT...SO WILL HAVE TO WAIT UNTIL LATE AFTERNOON WHEN INSTABILITY
IS MAXIMIZED. THEN FRONT/WIND SHIFT SHOULD BE OVER NORTHEAST
NEBRASKA...SO HAVE MAINTAINED A SMALL CHANCE FOR THUNDERSTORMS
THERE. BETTER CHANCES FOR STORMS WILL COME SUNDAY NIGHT INTO MONDAY
AS ANOTHER SHORTWAVE MOVES INTO THE PLAINS. MEANWHILE FRONTAL
BOUNDARY WILL SETTLE SOUTH SUNDAY NIGHT...THE LIFT BACK NORTH ON
MONDAY. COMBINATION OF TEMPERATURES CLIMBING INTO THE 90S AND
COOLING TEMPERATURES ALOFT WITH SHORTWAVE WILL PRODUCE CAPES
APPROACHING 3000 J/KG WITH 30KT OF 0-6KM BULK SHEAR MONDAY
AFTERNOON. SO WILL CONTINUE OUR SMALL CHANCES FOR STORMS SUNDAY
NIGHT AS BOUNDARY SETTLES SOUTH...AND HIGHER CHANCES MONDAY
AFTERNOON IN THE NORTH WHERE BOUNDARY/INSTABILITY WILL BE MAXIMIZED.
SOME SEVERE STORMS ARE POSSIBLE GIVEN INSTABILITY/SHEAR.
STORMS CHANCES SHOULD CONTINUE MONDAY NIGHT INTO TUESDAY AS FRONTAL
BOUNDARY REMAINS IN OUR AREA...REINFORCED BEHIND EXITING SHORTWAVE.
INSTABILITY WILL AGAIN APPROACH 3000 J/KG ALONG BOUNDARY TUESDAY
AFTERNOON...WITH A TAD GREATER SHEAR. SO AGAIN SEVERE IS POSSIBLE
TUESDAY AFTERNOON.
FRONT IS FORECAST TO SETTLE SOUTH OF OUR AREA ON WEDNESDAY...SO WILL
KEEP WEDNESDAY AND THURSDAY DRY. UPPER RIDGE BEGINS TO BUILD INTO
OUR AREA FRIDAY AND SATURDAY SIGNALING A RETURN TO WARMER
TEMPERATURES. AS RIDGE BUILDS...WARM ADVECTION REGIME ON FRIDAY
COULD SPARK STORMS...BUT DRY AFTER THAT AS MID LEVEL TEMPS WARM.
TEMPERATURES INTO MONDAY AND TUESDAY WILL EASILY REACH THE 90S...BUT
COULD HOLD IN THE 80S WHERE STORMS/CLOUDS LINGER. A LITTLE COOLER
WEDNESDAY AND THURSDAY WITH HIGHS IN THE 80S...BUT A RETURN TO 90S
LOOK LIKELY FRIDAY AND SATURDAY.
DERGAN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
344 AM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUL 7 2013
EARLY MORNING SURFACE ANALYSIS PLACED A WEAK SURFACE TROUGH ACROSS
EASTERN NORTH DAKOTA. THE TROUGH WAS THE FOCUS FOR ISOLATED
THUNDERSTORMS EARLIER THIS MORNING...BUT THEY HAVE SINCE
DIMINISHED. THE TROUGH WILL MOVE SLOWLY EAST THIS MORNING...TAKING
THE THREAT OF ADDITIONAL THUNDERSTORMS WITH IT.
THE NEXT CONCERN WILL BE SHOWERS / THUNDERSTORMS IN EASTERN
MONTANA WHICH HAVE BEEN MAKING STEADY PROGRESS TOWARDS WESTERN
NORTH DAKOTA EARLY THIS MORNING. THE STORMS IN EASTERN MONTANA ARE
IN PART BEING DRIVEN BY A SHORT WAVE WHICH IS EXPECTED TO MOVE
INTO WESTERN NORTH DAKOTA THIS MORNING...AND INTO CENTRAL NORTH
DAKOTA THIS AFTERNOON. VARIOUS MODEL SOLUTIONS (NAM / RAP / GFS /
4KM WRF) ALL SUGGEST THERE WILL BE A CHANCE OF PRECIPITATION AS
THE WAVE MOVES ACROSS THE FORECAST AREA. WHERE THEY DIFFER TO SOME
EXTENT IS IN THEIR COVERAGE OF PRECIPITATION. WILL HOLD ONTO
CHANCE POPS ACROSS MOST OF THE FORECAST AREA TODAY / THIS EVENING
WITH THE HIGHER POPS IN THE WEST. THE LATEST DAY 1 OUTLOOK PLACES
THE SOUTHWEST PART OF THE STATE IN A SLIGHT RISK...WHICH APPEARS
REASONABLE SINCE THAT AREA IS FORECAST TO HAVE THE GREATEST
INSTABILITY THIS AFTERNOON / EVENING WITH MLCAPE VALUES OF UP TO
1500 J/KG.
CONFIDENCE IN THUNDERSTORM COVERAGE LATE TONIGHT INTO EARLY MONDAY
MORNING DECREASES TO SOME EXTENT AS THE INITIAL WAVE MOVES EAST.
CONFLICTING SIGNALS ARE SHOWN IN THE MODEL SOLUTIONS WITH SOME
SUGGESTING LIMITED THUNDERSTORM COVERAGE OVERNIGHT...WHILE OTHERS
BRING ADDITIONAL THUNDERSTORMS INTO WESTERN NORTH DAKOTA FROM
EASTERN MONTANA. WILL HOLD ONTO CHANCE POPS IN THE CENTRAL AND
WEST...WITH SLIGHT CHANCES IN THE EAST WHERE CONFIDENCE IN
ADDITIONAL CONVECTION IS LOWER.
CLOUDS FROM SHOWERS / THUNDERSTORMS COULD INFLUENCE TEMPERATURES
TODAY. WILL FOLLOW A BLEND OF GUIDANCE VALUES WITH HIGHS NEAR 80
NORTH...AND LOWER TO MID 80S SOUTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUL 7 2013
MODELS AGREE IN A SOUTHWEST FLOW ALOFT FROM THE NORTHWEST US TO
THE NORTHERN PLAINS EARLY IN THE PERIOD. AN ACTIVE SHORTWAVE
PATTERN WILL BRING SEVERAL SHORTWAVES THROUGH THE REGION BRINGING
SOME WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE REGION MONDAY
NIGHT AND TUESDAY. THIS WILL BE FOLLOWED BY A BREAK IN THE
PRECIPITATION CHANCES WEDNESDAY AND THURSDAY AS AN H500 RIDGE
POSITIONS ITSELF OVER THE NORTHERN PLAINS. AS THIS FEATURE MOVES
EAST BY NEXT WEEKEND WILL SEE AT LEAST A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS RETURN FOR FRIDAY AND SATURDAY.
THE PRIMARY FOCUS WILL BE MONDAY NIGHT. BY MONDAY AFTERNOON LOW
PRESSURE WILL DEVELOP ACROSS MONTANA BRINGING A EASTERLY WIND FLOW
ACROSS WEST AND CENTRAL NORTH DAKOTA. THIS WILL PULL ABUNDANT
MOISTURE INTO THE REGION. MODEL SOUNDINGS FORECAST PWATS BETWEEN
1.5 AND 1.75 INCHES...OR ROUGHLY 2 STANDARD DEVIATIONS ABOVE
NORMAL IF CORRECT. WITH ABUNDANT MOISTURE WILL MENTION HEAVY RAIN
IN THE HWO ALONG WITH SLIGHT CHANCE SEVERE FROM SPC MONDAY NIGHT.
THUNDERSTORMS WILL END TUESDAY FOLLOWED BY THE DRY WEATHER
WEDNESDAYS AND THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 345 AM CDT SUN JUL 7 2013
WILL CARRY A VFR FORECAST AT THE TERMINAL LOCATIONS...BUT THERE
ARE A FEW CONCERNS. THE PRIMARY ISSUE WILL BE THE CHANCE OF
THUNDERSTORMS...ESPECIALLY NEAR KDIK LATER THIS MORNING AS SHOWERS
/THUNDERSTORMS ACROSS EASTERN MONTANA MOVE EAST INTO WESTERN NORTH
DAKOTA. CONFIDENCE IS NOT HIGH ENOUGH FOR A TEMPO GROUP...SO WILL
CARRY VCTS FOR NOW AND MONITOR THE TRENDS. THE REMAINDER OF THE
TAF LOCATIONS APPEAR TO HAVE LESSER CHANCES FOR THUNDERSTORMS THAN
KDIK...SO WILL NOT MENTION THEM AT THOSE TERMINALS. WINDS WILL
STAY RELATIVELY LIGHT THROUGH THE FORECAST PERIOD AT SPEEDS OF
LESS THAN 10 KTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CK
LONG TERM...WAA
AVIATION...CK
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
425 AM CDT SUN JUL 7 2013
.DISCUSSION...
LATEST RADAR IMAGERY SHOWS A LINE OF SHOWERS JUST REACHING THE
UPPER TX COAST THIS MORNING. THIS LINE OF SHOWERS APPEARS TO BE ON
THE LEADING EDGE OF HIGHER MOISTURE DELINEATED BY 2 INCH PRECIP
WATER VALUES NOTED ON GOES SOUNDER IMAGERY. UPPER LEVEL ANALYSIS
AND WATER VAPOR IMAGERY STILL SHOW A DEFORMING SHEAR AXIS WHICH
SEEMS TO BE IN THE PROCESS OF WEAKENING. PRESSURE GRADIENT AT THE
SFC HAS INCREASED SO GETTING SOME DECENT LOW LEVEL FLOW OFF THE
GULF WHICH SHOULD CONTINUE TO ADVECT HIGHER MOISTURE INLAND TODAY.
FOR THE MOST PART...GFS/ECMWF MODELS CONTINUE TO SHOW HIGHER
MOISTURE MOVE INTO SE TX THIS MORNING AND THROUGH THE EARLY
AFTERNOON. THE LATEST HRRR RUNS SEEMS TO SUPPORT THIS WITH
CONVECTION DEVELOPING INLAND MAINLY AROUND 15-16Z AND CONTINUING
THROUGH 22-23Z THIS AFTERNOON. ACTIVITY LOOKS MORE SCT IN NATURE
SO BACKED OFF ON POPS A TOUCH. STILL HAVE 60 POPS FOR THE I-10
CORRIDOR INCLUDING MOST OF HOUSTON. HEAVY RAINFALL THREAT WILL
LARGELY DEPEND ON INDIVIDUAL CELLS THAT BECOME STRONG AND FULLY
TAP DEEPER MOISTURE. GFS SHOWS PRECIP WATER VALUES GETTING TO
AROUND 2-2.2 INCHES WHICH WILL SUPPORT MODERATE TO HEAVY RAINFALL.
AGAIN MAIN FLOOD THREAT WILL BE URBAN IN NATURE WITH STORMS THAT
CAN QUICKLY PRODUCE 2 INCHES IN AN HOUR. OTHERWISE DRY GROUNDS
SHOULD BE ABLE TO ABSORB A LOT OF THE RUN OFF AND NOT CONTRIBUTE
TO FLOODING. WITH MOISTURE SLOWLY PUSHING INTO THE AREA...ALSO
INCREASED MAX TEMPS A COUPLE OF DEGREES AS CLOUD COVER WILL BE
SLOW TO FILL IN ACROSS THE AREA. LOOK FOR 1.8-2 INCH PW VALUES TO
REMAIN OVER SE TX THROUGH MONDAY SO WENT WITH 40/50 POPS FOR
SCATTERED ACTIVITY DURING THE DAY. AGAIN MOST OF THIS ACTIVITY
WILL BE DIURNALLY DRIVEN SO WILL HAVE LOWER POPS OVERNIGHT.
RAINFALL AMOUNTS AGAIN EXPECTED TO BE CONFINED TO THE COAST.
HOUSTON AREA MAY GET WIDE SPREAD HALF INCH AMOUNTS BUT THAT WILL
BE PUSHING IT. NORTH OF HOUSTON EXPECT RAINFALL AMOUNTS TO REALLY
DROP OFF AND AREAS FROM CONROE TO COLLEGE STATION MAY NOT SEE ANY
RAINFALL. BY AND LARGE THINK AREAS NORTH OF HOUSTON WILL AT MOST
GET 0.1-0.25 INCHES WITH 0.5-1 INCH AMOUNTS ALONG THE COAST. STILL
THINK HIGHEST MOISTURE WILL BE OFF TO THE EAST OVER LOUISIANA SO
RAINFALL AMOUNTS OF AN INCH OR MORE WILL BE IN THE GULF EASTWARD
THROUGH LOUISIANA. STILL DO NOT WANT TO RULE OUT A QUICK 2-3
INCHES IN SOME STRONGER CONVECTION BUT THINK THESE STORMS WILL BE
REALLY LOCALIZED AND NOT THE NORM.
IT LOOKS LIKE HIGHER MOISTURE OF 1.6-2 INCH PRECIP WATER VALUES
WILL LINGER TUE/WED SO WILL KEEP SOME 20/30 POPS IN THE FORECAST
FOR MAINLY AFTERNOON STORMS. MOISTURE DOES DECREASE THUR THROUGH
SAT SO HAVE POPS TAPERING OFF FROM 20 PERCENT TO NO RAIN CHANCES.
UPPER LEVEL PATTERN ALSO UNDERGOES SOME CHANGES DURING THIS TIME.
UPPER LEVEL RIDGE CURRENTLY OVER THE S ROCKIES REMAINS WEAK AND
NOT WELL ESTABLISHED FOR THE BEGINNING OF THE WEEK. BY THE END OF
THE WEEK THE RIDGE STRENGTHENS OVER THE C ROCKIES WITH ANOTHER
AMPLIFIED TROUGH OVER THE MID ATLANTIC BY FRIDAY. RIDGE WILL KEEP
LOWER THICKNESS HEIGHTS EAST OF THE AREA SO COULD SEE TEMPS
CREEPING UP TO UPPER 90S TO NEAR 100 FOR THE END OF THE WEEK.
TEMPS AT 850MB WHEN MIXED DOWN AT LEAST SUPPORT TEMPS IN THE UPPER
90S ACROSS THE AREA.
39
&&
.MARINE...
SCATTERED SHOWERS ARE MOVING THROUGH THE COASTAL WATERS THIS
MORNING ALONG THE LEADING EDGE OF DEEPER TROPICAL MOISTURE THAT
WILL CONTINUE TO PUSH INTO SOUTHEAST TEXAS TODAY. EXPECT SCATTERED
SHOWERS WITH PERHAPS AN ISOLATED THUNDERSTORM THROUGH MONDAY
ACROSS THE COASTAL WATERS. LIGHT TO MODERATE SOUTHEASTERLY WINDS
WILL CONTINUE THROUGH THE NEXT SEVERAL DAYS. WITH THE EASTERLY
COMPONENT TO THE WINDS WE WILL CONTINUE TO SEE TIDE LEVELS AROUND
1 TO 1.5 FEET ABOVE NORMAL VALUES. RIP CURRENTS WILL ALSO REMAIN
PROBLEMATIC FOR AREA BEACHES THROUGH THE WEEKEND. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 75 95 75 97 / 30 20 30 20 10
HOUSTON (IAH) 93 76 94 76 96 / 60 30 50 20 20
GALVESTON (GLS) 88 80 90 81 90 / 50 50 50 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
343 AM CDT SUN JUL 7 2013
.SHORT TERM...
DIRTY SOUTHWESTERN RIDGE HAS EXPANDED TO ENCOMPASS WEST TEXAS AND
THIS WILL PROVIDE ANOTHER TOASTY JULY DAY WITH HIGHS SIMILAR TO
SATURDAY. MID-LEVEL MOISTURE SPILLING OVER THE SOUTH PLAINS COUPLED
WITH WEAK ELEVATED INSTABILITY...DEEP LAYER MOISTURE CONVERGENCE AND
ELEVATED FRONTOGENESIS WERE SUPPORTING A FEW RECENTLY DEVELOPED
SHOWERS AND STORMS ACROSS THE FAR NORTHWESTERN ZONES. THIS ACTIVITY
WAS NOT MOVING MUCH THANKS TO WEAK STEERING FLOW/WINDS WITHIN THE
RIDGE...BUT WE COULD SEE AT LEAST ISOLATED ACTIVITY HANG ON ACROSS
THE WESTERN ZONES AND PERHAPS EXPAND/DEVELOP TOWARD THE I-27/US-87
CORRIDOR AS THE RECENT RAP AND HRRR RUNS SUGGEST. HENCE HAVE
INSERTED A SLIGHT CHANCE OF THUNDERSTORMS INTO THE GRIDS ACROSS THE
WESTERN AND INTO THE CENTRAL ZONES IN THE 12-18Z TIME-FRAME. ANY
ACTIVITY WILL LIKELY WANE TOWARD MID TO LATE MORNING. STRONG HEATING
AND SUFFICIENT MOISTURE WILL THEN YIELD ANOTHER ROUND OF CONVECTION
OVER THE HIGHER TERRAIN OF NM AND CO THIS AFTERNOON...BUT SIMILAR TO
SATURDAY...THIS ACTIVITY WILL NOT HAVE MUCH INCENTIVE TO MOVE VERY
FAR EASTWARD AND SHOULD STAY WELL WEST OF THE CWA. THE MID-LEVEL
MOISTURE PLUME WILL STILL EXTEND IN CLOSE PROXIMITY TO THE FAR
NORTHWESTERN ZONES LATE TONIGHT AND THERE MAY BE SOME RISK OF LATE
NIGHT ELEVATED CONVECTIVE DEVELOPMENT LIKE WE HAVE SEEN THE LAST
COUPLE OF NIGHTS. HOWEVER THE MID-LEVEL MOISTURE PLUME IS PROGGED TO
THIN/DRY A BIT LOCALLY AND LOW-LEVEL FORCING APPEARS LESS...SO HAVE
KEPT THE FORECAST DRY FOR TONIGHT. OTHERWISE...IT WILL BE ANOTHER
MILD NIGHT WITH LOWS VARYING FROM THE MID-60S NORTHWEST TO LOWER AND
MIDDLE 70S EAST.
&&
.LONG TERM...
AN UPPER LEVEL RIDGE...CENTERED ROUGHLY OVER THE 4-CORNERS INITIALLY...
AND GRADUALLY MIGRATING INTO THE CENTRAL HIGH PLAINS...WILL KEEP
THE FA HOT AND DRY FOR THE MOST PART THIS UPCOMING WEEK.
OROGRAPHICALLY FORCED CONVECTION WITHIN MOISTURE PLUME TRAPPED IN
THE RIDGE SHOULD REMAIN TO OUR WEST MONDAY WHILE AN INVERTED
TROUGH MOVING WEST ACROSS THE BIG BEND WILL BE OF LITTLE
CONSEQUENCE TO OUR WX. WE ARE STILL WATCHING FOR A TEMPORARY
WEAKNESS TO DEVELOP IN THE EASTERN PART OF THE RIDGE WED/THU AS A
SHORTWAVE MOVES FROM THE CANADIAN PRAIRIES TO THE GREAT LAKES AND
A COLD FRONT DIPS INTO SRN CO/SW KS. BUT ANY TSTM ACTIVITY
ASSOCIATED WITH THIS WAVE/FRONT APPEARS UNLIKELY TO MAKE IT INTO
OUR NRN ZONES LATE WED/EARLY THU. THEN...AS THE UPPER RIDGE RE-
EXPANDS E-NEWD WE EXPECT TEMPS TO NUDGE UPWARD A FEW DEGREES
HEADING INTO NEXT WEEKEND. EARLY NEXT WEEK...THE UPPER RIDGE MAY
START TO RETROGRADE BACK TO THE WEST AS AN UPPER TROUGH/LOW
DEVELOPS IN THE DEEP SOUTH. WE ARE COUNTING ON THIS PATTERN CHANGE
TO BRING A COOLING TREND AND PERHAPS A CHANCE OF RAIN NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 92 66 93 66 95 / 20 10 10 10 10
TULIA 94 67 95 68 96 / 20 10 10 10 10
PLAINVIEW 93 67 95 69 95 / 20 10 10 10 10
LEVELLAND 94 68 94 70 94 / 20 10 10 10 10
LUBBOCK 95 70 95 70 95 / 20 10 10 10 10
DENVER CITY 94 68 93 69 93 / 20 10 10 10 10
BROWNFIELD 95 69 94 70 95 / 20 10 10 10 0
CHILDRESS 99 71 98 74 99 / 0 0 0 0 0
SPUR 97 71 96 72 97 / 0 0 0 0 0
ASPERMONT 98 72 97 74 99 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
23/33
AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 AM MST SUN JUL 7 2013
.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE NEAR THE FOUR CORNERS REGION
THIS WEEK. ADEQUATE MOISTURE WILL PROVIDE ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS EARLY THIS WEEK WITH TEMPERATURES WELL
ABOVE AVERAGE. ANOTHER SURGE OF MOISTURE WILL LEAD TO INCREASED
THUNDERSTORM ACTIVITY BY WEDNESDAY.
&&
.DISCUSSION...STILL SORTING THROUGH SOME DEBRIS THIS MORNING FROM
OVERNIGHT CONVECTION IN NORTHWEST MEXICO. OVERALL WE HAVE A LITTLE
LESS MOISTURE TO WORK WITH AS SOME MID LEVEL DRYING TRIES TO WORK IN
BUT 12Z SOUNDING STILL HAD ABOUT 1.35 (IN LINE WITH BLENDED
SATELLITE ESTIMATES) WHICH IS PLENTY TO WORK WITH. STILL A WEAK
SOUTHERLY FLOW AT MOST LEVELS BUT A LITTLE BETTER THAN YESTERDAY.
NOT THE GREATEST WIND AND THERMAL PROFILE FOR STRUCTURE BUT OVERALL
SIMILAR TO YESTERDAY WITH SLIGHTLY BETTER SUPPORT FOR SLOW MOVING
STORMS WANDERING INTO SOME VALLEY LOCATIONS.
LATEST HI RES RR AND 12Z UOFA NAMWRF HAVE EASY DEVELOPMENT OVER
MOUNTAIN LOCATIONS ON SCHEDULE WITH BETTER COVERAGE BY MID TO LATE
AFTERNOON FOR SOME LOWER DESERT LOCATIONS SOUTHWEST AND WEST OF
TUCSON IN AN AREA OF WEAK MOISTURE CONVERGENCE. WE ADJUSTED FIRST
AND EARLY SECOND PERIOD TRENDS TO REFLECT THIS AS WELL AS A SLIGHT
INCREASE IN VALLEY COVERAGE OVERALL.
&&
.PREV DISCUSSION...HIGH PRESSURE ALOFT CENTERED OVER SRN NEW MEXICO
EARLY THIS MORNING. UPPER HIGH IS PROGGED TO DRIFT NWD TO THE FOUR
CORNERS REGION BY MON AFTERNOON...THEN REMAIN QUASI-STATIONARY THRU
THURSDAY. SUFFICIENT MOISTURE WILL YIELD ISOLATED-SCATTERED SHOWERS/
TSTMS MOSTLY FROM TUCSON EWD/SWD THIS AFTERNOON AND THIS EVENING.
COVERAGE OF SHOWERS/TSTMS IS EXPECTED TO GRADUALLY EXPAND WWD TO
ENCOMPASS THE ENTIRE CWA BY WED AFTERNOON AND WED EVENING.
THE 07/00Z ECMX MOS DEPICTS A SIGNIFICANT INCREASE IN POPS FOR KTUS
TUE. AM SOMEWHAT CONCERNED ABOUT A POTENTIAL GULF OF CALIFORNIA
SURGE AS EARLY AS TUE ATTRIBUTED TO TROPICAL SYSTEM ERICK. FOR NOW
HAVE MAINTAINED A GRADUAL POP INCREASE TUE VERSUS MON. THUS...CHANCE-
CATEGORY POPS EAST/SOUTH OF TUCSON TUE AFTERNOON AND TUE EVENING
WITH A SLIGHT CHANCE OF SHOWERS/TSTMS FROM TUCSON WWD.
POPS EXHIBIT A GRADUAL INCREASE WED-FRI AS DEEPER SELY FLOW IS
PROGGED TO OCCUR IN RESPONSE TO THE UPPER HIGH BECOMING POSITIONED
OVER THE CENTRAL CONUS. AT THIS TIME...TOO DIFFICULT TO DISCERN
WHICH DAY MAY BE THE PROVERBIAL UP-DAY...AND WHICH DAY MAY HAVE A
DOWNTURN IN CONVECTIVE ACTIVITY. AT ANY RATE...THERE IS A CHANCE OF
MAINLY AFTERNOON/EVENING SHOWERS/TSTMS FROM TUCSON EWD/SWD WED-FRI...
AND A SLIGHT CHANCE OF SHOWERS/TSTMS ACROSS WRN SECTIONS. HAVE
CONTINUED WITH A SLIGHT DECREASE IN PRECIP CHANCES SAT.
HIGH TEMPS FOR THE TUCSON METRO AREA THRU WED WILL AVERAGE ABOUT 3-5
DEGS F ABOVE NORMAL. DAYTIME TEMPS THUR-SAT ARE FORECAST TO BE
WITHIN A DEGREE-OR-TWO OF NORMAL.
&&
.AVIATION...VALID THRU 08/16Z...
ISOLD-SCT TSRA FROM THIS AFTERNOON THROUGH 08/06Z. THUNDERSTORM WIND
GUSTS 40-45 KTS WITH THE STRONGEST STORMS. OTHERWISE...12K FT
SCT-BKN THROUGH THIS MORNING BECOMING 12K FT SCT CLOUDS THIS
AFTERNOON WITH THE ISOLD-SCT TSRA. WIND GENERALLY AROUND 10 KTS AWAY
FROM THE THUNDERSTORMS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED TO SCATTERED THUNDERSTORMS EACH AFTERNOON
AND EVENING THROUGH TUESDAY ESPECIALLY IN THE HIGHER ELEVATIONS.
BECOMING SCATTERED THUNDERSTORMS FROM WEDNESDAY THROUGH THE END OF
THE WEEK. THE STRONGER THUNDERSTORMS WILL PRODUCE GUSTY AND ERRATIC
WINDS. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL OCCUR THROUGHOUT
THE WEEK. DAYTIME RELATIVE HUMIDITIES WILL RANGE FROM THE UPPER
TEENS TO 30S WITH GOOD NIGHTTIME RECOVERIES. AN INCREASE IN RELATIVE
HUMIDITY MID-WEEK COINCIDING WITH THE INCREASED STORM ACTIVITY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/BF/SAMPSON
AREA FORECAST DISCUSSION
NWS EUREKA CA
425 AM PDT SUN JUL 7 2013
.SYNOPSIS...EXPECT A TRANQUIL WEATHER PATTERN WITH SEASONAL
TEMPERATURES THIS WEEK. THE INTERIOR SHOULD BE MOSTLY CLEAR WHILE
THE COAST CAN EXPECT OVERNIGHT CLOUDS AND FOG WITH CLEARING EACH
AFTERNOON.
&&
.DISCUSSION...THE FORECAST REMAINS ON TRACK. CLOUDS OVER PORTIONS
OF NORTHWEST CALIFORNIA SHOULD DISSIPATE THIS MORNING AND
AFTERNOON, THOUGH PROBABLY NOT AS QUICKLY AS DAYS PAST SINCE THE
MARINE LAYER IS MORE ENTRENCHED ALONG THE COAST THIS MORNING. BUT
WHEN THE CLOUDS DO DISSIPATE ONE CAN EXPECT A NICE SUMMER DAY.
EXPECT A TRANQUIL WEATHER PATTERN WITH SEASONAL TEMPERATURES THIS
WEEK. SKIES WILL BE CLEAR ACROSS THE INTERIOR WITH SOME AFTERNOON
CLOUDS OVER THE HIGHER TERRAIN. WINDS THERE WILL BE MOSTLY LIGHT
AND TERRAIN-DRIVEN DURING THE DAY AND THEN LIGHT AND OFFSHORE AT
NIGHT. THE COAST CAN EXPECT OVERNIGHT CLOUDS AND FOG WITH CLEARING
EACH AFTERNOON. MINOR COOLING IS EXPECTED BY THE MIDDLE OF THE
WEEK AS A WEAK TROUGH PASSES OVER THE WEST COAST. BUT TEMPERATURES
SHOULD ONLY COOL A FEW DEGREES, MAINLY ACROSS THE INTERIOR.
&&
.AVIATION...LOW CLOUDS AND SOME LIGHT FOG CONTINUE TO HUG THE NW
CA COAST WITH CLOUDINESS EXTENDING INLAND UP THE COASTAL RIVER
VALLEYS N OF CAPE MENDO. AGREE WITH PREVIOUS FORECASTER WITH LATER
CLEARING TIME AT KACV TODAY. CURRENT TAF SET HAS ABOUT A 7 HOUR
WINDOW OF NO CIG AT KACV AND THIS MAY ACTUALLY NEED TO BE
NARROWED...BUT BOTH THE NAM AND RUC HINT THAT CLOUDINESS SHOULD
SCATTER OUT AROUND 21Z. TRICKIER FORECAST AT KCEC. NAM AND RUC
GRIDDED DATA SHOW MINIMAL CLOUD COVER DURING THE DAY...BUT NAM AND
GFS MOS SHOW CIGS MOST OF THE DAY. LOW CLOUDS HAVE EXPANDED N
ALONG THE COAST TO KCEC OVER THE PAST SEVERAL HOURS ON COASTAL S
FLOW. EXPECT NORTHERLIES TO RETURN LATER THIS MORNING. THIS...IN
CONCERT WITH EROSION FROM THE E DUE TO DAYTIME HEATING AND AN AREA
OF DOWNSLOPING UPSTREAM...MAY HELP CLOUDS ERODE BY LATE MORNING OR
EARLY AFTERNOON. LOW CLOUDS HAVE REACHED KSTS. WITH LIGHT S FLOW
AROUND THAT AREA...WILL NEED TO WATCH THIS CLOUD DECK IN CASE IT
MAKES A RUN AT KUKI. OTHERWISE...VFR EXPECTED AT THAT AIRPORT.
/SEC
&&
.MARINE...RATHER STRAIGHTFORWARD FORECAST DOMINATED BY SHORT
PERIOD WIND DRIVEN WAVES THRU THE PERIOD. HAVE EXTENDED THE N
OFFSHORE GALE WARNING THRU THE AFTERNOON HOURS DUE TO WIND GUSTS.
THIS MAY NEED TO BE EXPANDED FURTHER BY THE DAY SHIFT. OTHER
HEADLINES REMAIN UNCHANGED. SWAN MODEL APPEARS TO HAVE A BETTER
HANDLE ON WAVE HEIGHTS WITH INITIALIZATION MATCHING FAIRLY WELL
WITH LOCAL BUOYS. WINDS ARE FORECAST TO SLOWLY DECREASE INTO
TUE...THEN PICK UP A BIT AROUND MID-WEEK. /SEC
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
GALE WARNING FOR PZZ470.
HAZARDOUS SEAS WARNING FOR PZZ475.
SMALL CRAFT FOR PZZ450-455-475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
FOLLOW US ON FACEBOOK AND TWITTER AT:
HTTP://WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.EUREKA.GOV
HTTP://WWW.TWITTER.COM/NWSEUREKA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
641 AM EDT Sun Jul 7 2013
...UPDATED FOR HYDROLOGY SECTION...
.NEAR TERM [Today]...
Showers and isold tstms assocd with meeting of Gulf and east coast
seabreezes across Ern most counties late Sat eve weakened after
midnight. HRRR overforecast predawn precipitation over Wrn waters
and adjacent coastlines. Updated overnight grids to reflect this.
The large scale longwave blocking pattern continues to deamplify.
This is highlighted by a ridge over Wrn half of Conus, and a lifting
trough over Cntrl and Ern states with base over TN Valley and upper
low spinning from Mid Ms Valley into OH Valley. Looking east, a
ridge extends from high in Wrn Atlc a few hundred miles east of
Carolina coast WSW down South Atlc seaboard. Looking southeast, TUTT
low spinning invcnty of Bahamas. At the surface, Sly flow around Wrn
Atlc Bermuda high will remain over SE region.
During the rest of today, expect further lifting of low which will
reach Srn Great Lakes around sundown. This will allow Atlc high to
nose Swwd and deep layer ridge to encroach further inland pushing
tropical plume responsible for recent heavy rains further west of
our area. It will also combine with Wwd movement of TUTT placing CWA
closer to its subsident side. By this eve, TUTT actually moves under
ridge shifitng it back a little ewd. Lifting trough will also help
flatten Wrn and Atlc ridges and allow them to begin to bridge under
trough. However surface ridge axis remains to our north so ample low
level moisture remains. All this translates to increasing and strong
upper subsidence and dry air overspreading from the Atlc Swwd and
Nwwd to across local area. This reflected in model soundings which
show sharp W-E increase in mid level dry air and in decreasing PWAT.
i.e. GFS at 00z Mon with 1.79 in and 1.35 inches at TLH and JAX
respectively.
Thus scenario shifting somewhat to a more typical summertime pattern
of diurnal sea breeze convection especially east of the Apalachicola
River and with a continued sharp E-W POP/cloud gradient as reflected
in CAM and other High Res models. Will go with 20-60% SE-NW POP
gradient. Increasing dry air aloft should decrease aerial coverage
and delay onset of any storms compared to previous days. Although
the concentrated bands of heavy, flooding rains are not expected and
the flood watch has expired, soils over the Florida Panhandle and
into Southeast Alabama remain quite moist, so any rainfall could
cause some localized flooding issues if rainfall rates are high
enough. CAM flood tool still shows up to 30% possibility. With more
sunshine expected than recent days, temps should rebound back to
near seasonal levels with highs in the mid-upper 80s west to low 90s
east.
&&
.SHORT TERM [Tonight Through Tuesday]...
The blocky pattern of the past week will completely break down
during this period as the Midwest upper low opens up and ejects
east across New England by Monday night. The Atlantic ridge will be
further weakened as it is undercut by the TUTT low, which will reach
far South FL on Tuesday. These transformations will finally cut off
the flow of deep layer tropical air into the region and allow the
dry air seen on water vapor imagery over the Atlantic to work its
way westward into the forecast area. At the surface, the subtropical
ridge axis will extend across the Southeast U.S. through the period.
The ridge axis will be north of the area through Monday and then
slip to near the Gulf Coast on Tuesday. However, because of the
influence of drier air aloft, rain chances will actually dip to
below normal levels for this time of year, a refreshing change from
the recent rains. Of course, the flip side of getting less rain is
that temps will rise closer to seasonal levels. Highs Monday will be
near normal in the lower 90s. On Tuesday, we will actually see
slightly above normal max temps in the mid 90s across many inland
locations.
&&
.LONG TERM [Tuesday Night through Saturday]...
A fairly typical summertime pattern is expected with daily diurnal
convection through the period. By mid-week, an upper level low is
expected to approach from the southeast which could enhance rain
chances a little bit. Towards the end of the week as ridging builds
over the Plains, we may temporarily transition to more of a
northwest flow pattern with a weak front approaching from the
northwest. Near seasonal temperatures are expected.
&&
.AVIATION [Through 12z Monday]...
Lower ceilings/vsbys remain possible with all sites except ECP
possibly experiencing IFR conditions thru 13Z. By mid morning
hours, more showers and thunderstorms could develop around north
Florida with precipitation chances spreading to all other terminals
by the afternoon. DHN and ECP will have the highest chances of
receiving precipitation. Brief MVFR CIGS/VSBYS possible in any heavy
rain. VFR conditions are expected 00z-08z then MVFR CIGS/VSBYS again
possible 08Z-12Z where residual moisture remains from today`s rains.
&&
.MARINE...
A surface ridge of high pressure will become reestablished north of
the area this week allowing winds and seas to return to typical
summertime levels. Winds will generally be out of the east or
southeast.
&&
.FIRE WEATHER...
Red Flag conditions are not expected in the foreseeable future.
&&
.HYDROLOGY...
The overall threat for significant flooding has largely ended. Most
rivers across our area are either nearing their crest or have
recently crested. The greatest impacts continue to be on the
Choctawhatchee River at Bruce-Ebro which will reach major flood
stage. The Sopchoppy River moved above moderate flood overnight but
should gradually fall through today. The following rivers are at
minor stage. The Withlacoochee above Valdosta, St Marks near
Newport, Apalachicola near Blountstown, Choctawatchee at Caryville
and about to go into moderate flooding for today is the
Choctawhatchee at Geneva.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 73 91 72 94 / 50 20 40 20 30
Panama City 86 75 89 74 91 / 60 20 40 20 20
Dothan 88 73 91 72 95 / 60 30 40 20 30
Albany 91 74 92 73 94 / 60 30 40 20 30
Valdosta 91 72 92 70 93 / 30 20 40 20 30
Cross City 92 70 93 69 94 / 20 20 30 20 30
Apalachicola 86 74 88 74 89 / 50 20 30 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
Near Term/Aviation/Fire Weather...Block
Long Term...DVD
Hydrology...Block/Wool
Rest of Discussion...Wool
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
730 AM EDT SUN JUL 7 2013
.PREV DISCUSSION... /ISSUED 355 AM EDT SUN JUL 7 2013/
SHORT TERM /TODAY THROUGH MONDAY/...
WATER VAPOR LOOP CONTINUES TO SHOW DEEP MOISTURE BEING FUNNELED INTO
W GA FROM THE TROPICS. PWATS HAVE BUMPED BACK UP TO AROUND 2 INCHES
ACROSS NORTHERN GA ACCORDING TO THE 00Z FFC SOUNDING. MODELS SHOW
THIS HIGH MOISTURE AXIS REMAINING ACROSS THE CWFA THROUGH TONIGHT.
SOMEWHAT DRIER AIR HAS MOVED IN ACROSS THE EASTERN PORTION OF THE
CWFA.
UPPER LOW ACROSS THE OHIO VALLEY WILL SLOWLY EJECT INTO THE MIDDLE
ATLANTIC BY EARLY MONDAY MORNING. MEANWHILE...THE BERMUDA HIGH AT
THE SURFACE WILL BEGIN TO BUILD WESTWARD...ALSO HELPING SHIFT THE
TROPICAL PLUME WESTWARD. THIS SHOULD RESULT IN A DECREASE IN
PWATS/MOISTURE CONTENT DURING THE DAY ON MONDAY.
LATEST RUNS OF THE HRRR SHOW THE BEST CHANCE FOR POPS IS IN NW GA
THIS MORNING. THIS SEEMS REASONABLE AS PRECIP AXIS HAS NOT MOVED
MOST OF THE NIGHT. SCT/NMRS SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS THE REMAINDER OF THE CWFA THIS AFT/EVE BUT THEY SHOULD BE
MORE DIURNALLY DRIVEN.
FFG IS LESS THAN AN INCH AND A HALF ACROSS AREAS MOSTLY NORTH OF THE
FALL LINE. WILL NOT MAKE ANY CHANGES TO THE FLOOD WATCH FOR NOW.
NLISTEMAA
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
EXTENDED BEGINS WITH UPPER WAVE MOVING OFF THE NEW ENGLAND COAST
WHILE CLOSED LOW OVER THE BAHAMAS IS WORKING ITS WAY WEST...AND
BETWEEN THESE TWO THE ATLANTIC HIGH IS RIDGING INTO THE SOUTHEAST.
THE EXITING SYSTEM ACROSS NEW ENGLAND ALLOWS THE ASSOCIATED
SURFACE BOUNDARY/FRONT TO ELONGATE AND STRETCH ACROSS THE
SOUTHEAST. BEST PRECIP CHANCES WILL BE ACROSS NORTH GEORGIA.
ANOTHER LONGWAVE TROUGH PUSHES INTO SOUTHERN CANADA AND THE UPPER
MISSISSIPPI VALLEY BY MIDWEEK AND WITH CONTINUE SOUTHERLY FLOW
FROM THE ATLANTIC AND GULF...PRECIP CHANCES INCREASE AGAIN
WEDNESDAY AND ESPECIALLY INTO THURSDAY AS THE TROUGH DIGS INTO THE
OHIO VALLEY AND A SURFACE FRONT MOVES INTO THE TENNESSEE VALLEY.
REALLY REMARKABLE AGREEMENT BETWEEN THE GFS AND ECMWF THROUGH THIS
PERIOD...THOUGH THE ECMWF IS A TAD DEEPER WITH THE WAVE INTO THE
SOUTHEAST AND A LITTLE BIT MORE NEGATIVELY TILTED.
LATE IN THE WORK WEEK THIS TROUGH CONTINUES TO DIG AND DEEPEN INTO
THE GREAT LAKES...EVENTUALLY FORMING A CUTOFF LOW OVER THE UPPER
OHIO VALLEY. GFS A LITTLE FASTER WITH THIS TRANSITION BUT STILL
PRETTY SIMILAR IN OVERALL DEPICTION. TROUGH AXIS PROGGED TO BE
GENERALLY ACROSS THE MIDDLE OF THE STATE...THUS REDUCING PRECIP
CHANCES ACROSS NORTHWEST GEORGIA BUT KEEPING POPS IN SOUTHEAST
ZONES. THE LOW CONTINUES TO DEEPEN AND DIG TO THE SOUTHWEST...
RETROGRADING IN RESPONSE TO DEEPENING UPPER HIGH OVER THE DESERT
SOUTHWEST AND WESTERN PLAINS. BY THE END OF THE PERIOD THE CUTOFF
LOW IS SOMEWHERE EITHER IN THE TENNESSEE VALLEY OR SOUTHEAST...
WITH BOTH MODELS CONTINUING TO RETROGRADE IT TO THE WEST BEYOND
THE END OF THE PERIOD. SO IN GENERAL...IT LOOKS LIKE NEXT WEEK
COULD BE A REPEAT OF WHAT WE SAW THIS PAST WEEK WITH SIGNIFICANT
MOISTURE TRANSPORT OUT OF THE GULF. WILL WAIT AND SEE HOW THIS
PLAYS OUT.
TEMPS REMAIN AT OR BELOW NORMAL THROUGH THE PERIOD. IF WE HAVE TO
PUT UP WITH ALL THE RAIN AND POTENTIAL FLOODING...AT LEAST WE GET
COOLER TEMPS OUT OF IT. HOWEVER...THERE IS A LARGER CONCERN THAT
WITH THIS CONTINUED WET PATTERN WE COULD BE SETTING THE STAGE FOR
SOME REAL PROBLEMS IF WE GET A TROPICAL SYSTEM MOVING IN.
TDP
AVIATION...
06Z UPDATE...
TROPICAL MOISTURE PLUME CONTINUES ACROSS THE REGION. MODELS ARE
SUPPORTING IFR CIGS AT MANY OF THE AIRPORTS THROUGH EARLY SUNDAY
MORNING. THE 00Z NAM SOUNDINGS SUPPORT THIS. IN ADDITION...PATCHY
MVFR FOG WILL ALSO BE POSSIBLE. SKIES SHOULD REMAIN MCLDY THROUGH
THE DAY WITH CIGS BKN AROUND 035-040. SHRA/TSRA WILL DEVELOP
DURING PEAK HEATING. LOW CIGS ARE POSSIBLE AGAIN TOMORROW NIGHT.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE FOR WINDS. MEDIUM CONFIDENCE REMAINING ELEMENTS.
&&
.AVIATION...
12Z UPDATE...
IFR CIGS SHOULD LIFT TO MVFR BY 14-15Z AT ATL. SKIES WILL REMAIN
BKN THROUGH THE DAY...BUT VALUES SHOULD BE AROUND 035. DIURNALLY
DRIVEN CONVECTION EXPECTED THIS AFTERNOON. LATEST RUN OF THE HRRR
HAS BULF OF CONVECTION DEVELOPING JUST TO THE SOUTH OF ATL THIS
AFTERNOON...BUT WILL KEEP THE TEMPO GROUP IN DURING PEAK HEATING.
DO THINK COVERAGE WILL BE NMRS. LOW CIGS AGAIN TONIGHT...MAY HAVE
TO TWEAK TAFS LATER TO IFR VALUES.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 82 70 86 71 / 70 40 50 30
ATLANTA 81 70 84 72 / 70 40 50 30
BLAIRSVILLE 75 67 78 66 / 70 50 60 30
CARTERSVILLE 80 69 86 69 / 70 40 60 30
COLUMBUS 84 73 89 73 / 70 30 50 20
GAINESVILLE 79 68 83 71 / 70 50 60 30
MACON 86 73 88 72 / 70 30 50 20
ROME 80 70 86 70 / 70 50 60 30
PEACHTREE CITY 81 70 84 70 / 70 40 50 30
VIDALIA 89 72 90 73 / 50 20 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
BANKS...BARROW...BARTOW...CARROLL...CATOOSA...CHATTOOGA...
CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...DADE...DAWSON...
DEKALB...DOUGLAS...FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...
GORDON...GREENE...GWINNETT...HALL...HARALSON...HEARD...HENRY...
JACKSON...LUMPKIN...MADISON...MORGAN...MURRAY...NEWTON...NORTH
FULTON...OCONEE...OGLETHORPE...PAULDING...PICKENS...POLK...
ROCKDALE...SOUTH FULTON...TALIAFERRO...TOWNS...UNION...WALKER...
WALTON...WHITE...WHITFIELD...WILKES.
&&
$$
SHORT TERM...ATWELL
LONG TERM....ATWELL
AVIATION...ATWELL
AREA FORECAST DISCUSSION...CORRECTION
NWS WAKEFIELD VA
1130 AM EDT SUN JUL 7 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE CAROLINA COAST TODAY...BEFORE
DRIFTING SOUTHEAST MONDAY AS LOW PRESSURE LIFTS THROUGH THE
NORTHEAST STATES. THE ASSOCIATED FRONTAL BOUNDARY DROPS THROUGH THE
MID ATLANTIC MONDAY AND DISSIPATES OVER THE CAROLINAS TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST IR/WV SAT IMAGERY SHOWING AN UPPER LOW OVER IN/IL AT 15Z THIS
MORNING. A MOIST FRONTAL PLUME WAS NOTED FLOWING NORTHWARD AHEAD
OF THE LOW FROM THE EASTERN GULF COAST TO THE EASTERN GREAT LAKES.
MEANWHILE...SUBTROPICAL HIGH PRESSURE (SFC AND ALOFT) REMAINS
ANCHORED OFF THE CAROLINA COAST.
NO MAJOR CHANGES NECESSARY TO THE GOING FORECAST ATTM. THE UPPER
SYSTEM IS WILL CONTINUE TO SLOWLY LIFT TOWARD THE EASTERN GREAT
LAKES TODAY...WITH THE FRONTAL BAND SLOWLY MOVING EASTWARD OVER
THE APPALACHIANS. THERE IS A LACK OF SYNOPTIC SCALE FORCING TODAY
TO TRIGGER CONVECTION LOCALLY DESPITE A RATHER UNSTABLE
ENVIRONMENT. HRRR CONTINUES TO PICK UP ON THIS TREND WELL,
YIELDING ONLY AN ISOLATED TSRA OR TWO AT MOST THROUGH 22Z/6PM.
ACCORDINGLY...HAVE PUSHED BACK POPS WITH SLOWER ONSET THROUGH THIS
TIME FRAME, ORIENTING ISO T WORDING ALONG AND WEST OF HIGHWAY 15
IN THE FAR NW PIEDMONT COUNTIES.
THERE IS VERY LITTLE CHANGE IN THE LOW-LEVEL THERMAL PROFILE, AND
THUS HV STUCK CLOSE TO A PERSISTENCE FORECAST FOR TODAY`S MAXIMA.
LOOK FOR HIGHS RISING INTO THE UPPER 80S IMMEDIATE COAST...TO LOW
90S INLAND. DEWPOINTS SHOULD MIX DOWN INTO THE UPPER 60S DURING
PEAK HEATING...HENCE RESULTANT HEAT INDICES SHOULD ONLY BE A FEW
DEGREES HIGHER THAN THE AMBIENT TEMPERATURE. SKY COVER
CHARACTERIZED AS PARTLY SUNNY WEST TO MOSTLY SUNNY EAST FOR THE
BALANCE OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
THE UPPER LOW LIFTS ACROSS THE NORTHEAST AND DAMPENS TONIGHT AND
MONDAY...WITH THE FRONTAL BAND DROPPING INTO THE MID ATLANTIC.
LATEST NUMERICAL GUIDANCE BRINGS THE MOISTURE PLUME INTO THE REGION
MONDAY MORNING AND SLOWLY DROPS IT SE INTO SE VA AND NE NC BY THE
AFTERNOON. THE EARLIER TIMING (EARLIER ARRIVAL OF MID-CLOUDS) ALONG
WITH MOIST ADIABATIC MID-LEVEL LAPSE RATES HAMPERS POTENTIAL
INSTABILITY...WHICH WOULD LIMIT CONVECTIVE COVERAGE MONDAY AFTERNOON.
ADDITIONALLY...THE MID/UPPER LEVEL FLOW BECOMES MORE ZONAL...WHICH
WOULD FURTHER LIMIT COVERAGE. GIVEN THIS...HAVE LOWERED POPS TO
LOW-END CHANCE.
0-6KM BULK SHEAR VALUES ARE STILL PROGGED TO REACH 25-30KT...SO
THERE IS A POSSIBILITY OF ISOLATED STRONGER THUNDERSTORMS IF A FEW
POCKETS OF HIGHER INSTABILITY DO DEVELOP. THE MAIN THREAT WOULD BE
BRIEF HEAVY RAIN AND STRONG WIND GUSTS.
THE BOUNDARY WASHES OUT TUESDAY AS ZONAL PREVAILS ACROSS THE REGION.
GFS/NAM EACH INDICATE AROUND 1500-1800 J/KG OF MLCAPE TUESDAY
AFTERNOON. HOWEVER...DEEP LAYER SHEAR WILL BE MUCH LESS ALONG WITH
LITTLE SYNOPTIC SCALE FORCING. THE HIGHER TERRAIN TO THE WEST WILL
LIKELY BE THE TRIGGER FOR ANY THUNDERSTORMS...SOME OF WHICH COULD
DRIFT EAST INTO THE PIEDMONT...SO CHANCE POPS WILL BE MAINTAINED
THERE WITH SLIGHT CHANCE FARTHER EAST.
SEASONABLY HOT (ALTHOUGH NOT EXCESSIVE) AND HUMID CONDITIONS WILL
CONTINUE MONDAY AND TUESDAY. HIGHS SHOULD RANGE FROM THE UPPER 80S
TO LOW 90S...ALONG WITH LOWS IN THE LOW/MID 70S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LONG TERM PERIOD STARTS OFF TUE NGT INTO WED WITH ZONAL FLOW ALOFT
OVER THE MID ATLANTIC AND AN UPR-LVL LO STARTING TO DIG OVER THE
GREAT LAKES REGION. ALTHO BEST FORCING AND MOISTURE WILL STAY NW OF
THE LOCAL AREA WED...DID INCLUDE A 20-30% CHC FOR SHRAS/TSTMS DUE TO
DIURNALLY-DRIVEN CONVECTION IN THE WARM SECTOR. BETTER CHC FOR RAIN
(40-50%) COMES LATE THU AS THE UPR-LVL TROF AND ASSOCIATED COLD FRONT
APPROACH FROM THE OH VALLEY AND DEEP-LAYER MOISTURE INCREASES. THE
FRONT WILL SLOW DOWN/STALL OVER THE AREA FRI (AND ALSO SAT?) LEADING
TO CONTINUED CHCS FOR SHRAS/TSTMS.
SLY FLOW AND ABUNDANT LO-LVL MOISTURE WILL CONTINUE TO PRODUCE HUMID
CONDS (DEWPTS AVG IN THE LWR 70S) WITH HI TEMPS IN THE UPR 80S/LWR
90S AND LO TEMPS AVG IN THE LWR 70S.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS AND RELATIVELY LIGHT WINDS ARE EXPECTED THROUGH THE
TAF PERIOD. ISOLD AFTN TSMS ARE POSSIBLE THIS AFTERNOON...MAINLY
WEST OF KRIC.
OUTLOOK...SCATTERED TSTMS...MAINLY AFTN/EVE WILL BE POSSIBLE MON-
WED. MORE WIDESPREAD PCPN IS POSSIBLE LATE IN THE WEEK.
&&
.MARINE...
GENERALLY BENIGN SUB-SCA CONDITIONS OVER THE MARINE AREA THRU AT
LEAST THE MIDDLE OF THE COMING WEEK. BERMUDA HIGH PRESSURE WILL
SLOWLY WEAKEN/DRIFT EASTWARD TODAY THRU TONIGHT AS A LOW PRESSURE
SYSTEM APPROACHES FROM THE WEST. NO STRONG SFC FRONT WILL BE
ASSOCIATED WITH THIS SYSTEM. WINDS THRU MIDWEEK WILL AVG 10-15 KT
OUT OF THE S/SW. EXPECT 1-2 FT WAVES OVER THE BAY AND 2-3 FT SEAS
OVER COASTAL WATERS...APPROACHING 4 FT OUT 20 NM ON MON AND AGAIN
WED.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...AJZ
NEAR TERM...AJZ/MAM
SHORT TERM...AJZ
LONG TERM...MAS
AVIATION...JDM/DAP
MARINE...JDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1050 AM EDT SUN JUL 7 2013
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 314 AM EDT SUN JUL 7 2013
THE WEATHER PATTERN WILL CHANGE LITTLE OVER THE NEXT FEW DAYS. IT
WILL REMAIN WARM AND HUMID WITH HIGHS IN THE MID TO UPPER 80S. WE
WILL ALSO SEE SCATTERED SHOWERS AND STORMS. THE BEST CHANCE OF
PRECIPITATION IN THE SHORT TERM WILL COME LATE TONIGHT INTO MONDAY
MORNING...WITH ANOTHER GOOD CHANCE ON TUESDAY.
THE SHOWERS AND STORMS SHOULD LINGER INTO WEDNESDAY...BUT THEN THE
LATTER HALF OF THE WEEK LOOKS DRY. DAYTIME TEMPERATURES WILL
LARGELY BE IN THE 80 TO 85 DEGREE RANGE FROM MID WEEK INTO NEXT
WEEKEND.
&&
.UPDATE...
ISSUED AT 1048 AM EDT SUN JUL 7 2013
I UPDATED THE ZONE FORECAST TO INCREASE THE CHANCE FOR SHOWERS
INTO EARLY THIS AFTERNOON OVER THE EASTERN SECTIONS OUR OUR CWA
AND TO DECREASE THE FORECAST HIGH A TOUCH SINCE THERE IS A
CONSIDERABLE AMOUNT OF MID CLOUD AROUND.
THE 700 MB LOW IS NEARLY OVERHEAD OF GRAND RAPIDS AT 9 AM BASED ON
RADAR DATA SHOWING THE SHOWERS PINWHEELING AROUND GRAND RAPIDS.
THIS IS ALSO SUPPORTED BY BOTH VISIBLE SATELLITE LOOPS AND RAP
MODEL 12Z FORECAST. THAT SUPPORTS THE SHOWERS OVER THE INFLOW
SECTION OF THE LOW...EAST OF GRR ACTUALLY WITH A DEFORMATION ZONE
FEATURE FROM NORTHERN KENT COUNTY INTO GRATIOT COUNTY. NOT MUCH
THUNDER HAPPENING THOUGH. WHILE THAT WAS HAPPENING THERE IS AN MCS
OVER THE WESTERN UPPER PENINSULA OF MICHIGAN THAT SEEMS TO BE
WEAKENING AND BUILDING TOWARD THE SOUTHEAST.
WITH THE 700 MB LOW WEAKENING AND MOVING INTO EASTERN LOWER
MICHIGAN THIS AFTERNOON THAT WOULD PUT WESTERN LOWER MICHIGAN IN
NORTHWEST SUBSIDING FLOW ON THE WEST SIDE OF THE LOW. NOT A GOOD
THING IF ONE WANTS SHOWERS. SO MY SPIN IS THE CLOUDS AND SHOWERS
WILL GRADUALLY MOVE EAST OF SOUTHWEST LOWER MICHIGAN DURING THE
AFTERNOON. WITH THE SUBSIDENCE ON THE WEST SIDE OF THE SYSTEM I DO
NOT SEE MUCH THREAT FOR CONVECTION TO DEVELOP SO I HAVE VERY LOW
POPS WEST OF US-131 AFTER 1 PM (WEST WINDS OFF LAKE MICHIGAN DO
NOT HELP THE CAUSE FOR CONVECTION MUCH EITHER).THIS IS STRONGLY
SUPPORTED BY RAP MODEL SOUNDING WITH SHOW A VERY DRY LOOKING
SOUNDING FROM THE SURFACE THROUGH 300 MB BY 21Z NEAR GRR.
IT IS MORE MOIST ON THE RAP SOUNDING IN THE LAN/JXN AREA THIS
AFTERNOON WITH NEAR 1800 J/KG OF CAPE BUT I WITH GENERIC WEST WINDS
THROUGH 700 MB BY 21Z I SEE LITTLE REASON FOR MUCH SURFACE
CONVERGENCE SO I AM STILL NOT TO EXITED ABOUT STORM POTENTL EVEN THERE.
WE WILL HAVE TO WATCH WHAT HAPPENS WITH THE MCS OVER THE WESTERN
UPPER PENINSULA FOR THIS EVENING BUT EVEN THERE... THE LOW LEVEL
JET IS LARGELY IN WISCONSIN THIS EVENING AND THE BEST JET DYNAMICS
ARE OVER NORTHERN WI AND THE MICHIGAN UP SO I BELIEVE LITTLE WILL
HAPPEN OVER WESTERN LOWER MICHIGAN TONIGHT EITHER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 314 AM EDT SUN JUL 7 2013
WIDELY SCATTERED SHOWERS AND STORMS WILL CONTINUE THROUGH THE SHORT
TERM. HOWEVER THE PRECIPITATION SHOULD BECOME MORE WIDESPREAD LATE
TONIGHT INTO MONDAY MORNING...AND THEN AGAIN ON TUESDAY. IT WILL
REMAIN WARM AND HUMID THROUGH TUESDAY.
AN UPPER LOW WAS OVER SE IL THIS MORNING AND IT WAS DRIFTING NE.
THIS WILL BRING THE CENTER OF THE LOW TO NE INDIANA BY THIS
AFTERNOON. THIS IS FURTHER NORTH THAN WHAT PREVIOUS MODELS HAVE
BEEN SHOWING. FOR THE PAST FEW DAYS THERE HAS BEEN DAYTIME
THUNDERSTORMS NEAR AND AROUND THIS LOW. HOWEVER THE COVERAGE OF THE
PCPN STILL WARRANTS 30/40 POPS. ALSO BY THE END OF THE DAY A COLD
FRONT WILL BE MOVING ACROSS WI. THIS COULD BRING ISOLATED PCPN INTO
THE NW CWA AND 20/30 POPS WILL BE CARRIED OVER THE NW CWA.
DECENT SET UP FOR AN MCS TO ROLL ALONG THE FRONT TO OUR WEST TONIGHT
WITH THE ASSISTANCE OF A LOW LEVEL JET. SEEMS LIKE THIS MAY TRACK
NEAR THE MI/IN BORDER LATE TONIGHT IN A WEAKENING STATE. ITS
DOUBTFUL THAT SEVERE WILL OCCUR AS THIS COMPLEX WILL BE RUNNING AWAY
FROM THE BEST INSTABILITY AND JET SUPPORT BY THE TIME IT REACHES
US...BUT WILL CARRY 40/50 POPS SOUTH OF I-96.
EXPECT SOMEWHAT LESS CONVECTION INTO MONDAY AFTERNOON AND MONDAY
NIGHT. THE FRONT EASES INTO THE REGION...BUT IT WASHES OUT OVER THE
NORTHERN OR CENTRAL CWA. THIS MAY SUPPORT SOME WIDELY SCATTERED
STORMS BUT WITHOUT A FOCUSED JET THESE SHOULD NOT BE SEVERE.
ANOTHER UP TICK IN THE STORM ACTIVITY IS EXPECTED INTO TUESDAY.
ANOTHER COLD FRONT WILL BE CROSSING WI WITH A STRONG LOW LEVEL JET
ALONG IT. THE CONVERGENCE FROM THIS JET SHOULD REACH US BY LATE
AFTERNOON WHEN THE CHANCE OF ORGANIZED/SEVERE STORMS WILL BE
POSSIBLE. HAVE INCREASED POPS TO LIKELY SOUTH OF I-96 AS THIS IS
WHERE THE LLJ IS PROGGED TO BE NOSING INTO.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN JUL 7 2013
BEST CHANCE OF RAIN IN THE EXTENDED WILL BE TUESDAY NIGHT INTO
EARLY WEDNESDAY AS UPPER TROUGH AXIS AND SFC LOW MOVES THROUGH.
PLENTY OF MOISTURE AVAILABLE AND MCS DEVELOPMENT IS POSSIBLE TUESDAY
NIGHT INTO WEDNESDAY MORNING WITH HEAVY RAIN THREAT. MODELS HAVE
TRENDED TO A LESS AMPLIFIED TROUGH AND WEAKER SHEAR PROFILES SO
SEVERE THREAT NOW SEEMS TO BE DIMINISHED.
KEPT THE LATTER PART OF THE WEEK DRY AS SFC HIGH IS IN PLACE AND DRY
SOUNDINGS RULE FROM LATE WEDNESDAY THROUGH THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 745 AM EDT SUN JUL 7 2013
SOME AREAS OF MVFR IN LIGHT FOG WITH ISOLATED IFR LOW STRATUS
EARLY THIS MORNING WILL IMPROVE TO VFR BY 14Z. ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED THROUGH THE DAY.
WINDS WILL BE SOUTHWEST AOB 10 KNOTS.
&&
.MARINE...
ISSUED AT 314 AM EDT SUN JUL 7 2013
SOUTHERLY WINDS ARE EXPECTED TO INCREASE TONIGHT AHEAD OF AN
APPROACHING COLD FRONT. AREAS NORTH OF HOLLAND WILL SEE WAVES
INCREASE TO 2-3 FEET. THIS IS BELOW SMALL CRAFT CRITERIA...BUT THE
LAKE WILL STILL BECOME RATHER ROUGH. WINDS AND WAVES ARE EXPECTED
TO RELAX INTO MONDAY AS THE FRONT MOVES IN.
&&
.HYDROLOGY...
ISSUED AT 314 AM EDT SUN JUL 7 2013
THE WIDELY SCATTERED SHOWERS SHOULD RESULT WITH MOST RIVER BASIN
SEEING AN AVERAGE OF AROUND A QUARTER INCH OF RAIN THROUGH MONDAY
NIGHT...PERHAPS A BIT HIGHER SOUTH OF I-96.
A BETTER CHANCE FOR WIDESPREAD RAINS COMES IN ON TUESDAY. EXPECT
AREAS INLAND FROM THE LAKE AND SOUTH OF HIGHWAY 20 WILL STAND THE
BEST CHANCE OF SEEING A HALF INCH OR MORE OF RAIN. LOCALIZED
HEAVIER RAINS MAY OCCUR AND PRODUCE NUISANCE FLOODING...BUT IN
GENERAL NO HYDRO ISSUES ARE EXPECTED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...JK
MARINE...JK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1030 AM EDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 1030 AM EDT SUN JUL 7 2013
REMNANTS OF OVERNIGHT MCS CONTINUE TO MOVE IN THE EASTERN U.P. THIS
MORNING AS THEY CONTINUE TO DIMINISH. TRAINING STORMS EARLIER THIS
MORNING DUMPED BETWEEN 2 AND 4 INCHES OF RAIN ACROSS GOGEBIC AND
ONTONAGON COUNTIES BUT AMOUNTS HAVE BEEN MUCH LIGHT FARTHER EAST.
EXPECT A BREAK IN PRECIPITATION INTO THE AFTERNOON HOURS. HIRES
MODELS CONTINUE TO SHOW SCATTERED REDEVELOPMENT OCCURRING ALONG THE
SURFACE TROUGH THIS AFTERNOON AS IT SAGS SOUTHWARD. STILL SOME
UNCERTAINTY THERE AND WILL HAVE TO MONITOR THROUGH THE AFTERNOON
HOURS. WILL ADJUST POP FORECAST ACCORDINGLY WITH THAT THOUGHT
PROCESS IN MIND. WITH MORE CLOUDS TODAY...TEMPS SHOULD ONLY CLIMB
INTO THE UPPER 70S TO AROUND 80.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT SUN JUL 7 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA WITH A CUTOFF MID/UPPER LEVEL LOW TO
THE SOUTH OVER IL/IN. A SHORTWAVE TROUGH COMBINED WITH UPPER LEVEL
DIV WITH THE RIGHT ENTRANCE OF A 75 KNOT 250 JET OVER NRN
ONTARIO...AND FAVORABLE 925-700 THETA/E ADVECTION FROM THE UPPER MS
VALLEY SUPPORTED AN AREA OF SHRA/TSRA OVER LAKE SUPERIOR INTO W
UPPER MI AND NW WI WITH THE STRONGEST CONVECTION ON THE WRN END OF
THE PCPN AREA. AT THE SFC...A COLD FRONT HAD GRADUALLY SAGGED TO THE
SOUTH INTO NRN UPPER MI.
TODAY...EXPECT THAT WEAKENING SHRA/TSRA WILL CONTINUE TO SPREAD
THROUGH WRN INTO N CNTRL UPPER MI EARLY...PER RADAR AND SHORT RANGE
MODEL TRENDS...BEFORE THE FORCING ASSOCIATED WITH THE SHRTWV AND LOW
LEVEL INFLOW WEAKENS. BY LATE MORNING INTO THE EARLY
AFTERNOON...THERE MAY BE A LULL IN ANY PCPN BEFORE ADDITIONAL SCT
SHRA/TSRA ALONG THE FRONTAL BOUNDARY REINFORCED BY LAKE SUPERIOR
BREEZE. THERE MAY BE ENOUGH THINNING OR BREAKS IN THE CLOUD COVER
FOR TEMPS TO RECOVER TO NEAR 80...PUSHING MLCAPE VALUES INTO THE
1000-1500 J/KG RANGE. HOWEVER...0-6KM SHEAR VALUES TO NEAR 30 KT
WILL REMAIN MARGINAL FOR STRONGER OR SEVERE ORGANIZED CONVECTION.
THERE MAY STILL BE BRIEF HEAVY RAIN AND GUSTY WINDS WITH TSRA THAT
DEVELOP.
TONIGHT...AS DAYTIME HEATING SUBSIDES AND THE FRONT CONTINUES TO
PUSH TO THE SOUTH...THE REMAINING PCPN SHOULD SHIFT TO THE SOUTH AND
EAST AND DIMINISH. WITH LINGERING LOW LEVEL MOISTURE AND MID LEVEL
DRYING...AREAS OF FOG ARE EXPECTED TO DEVELOP. THERE COULD ALSO BE
SOME DRIZZLE NEAR THE WRN SHORE AS WEAK LOW LEVEL CONV DEVELOPS WITH
MOIST NE FLOW OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 505 AM EDT SUN JUL 7 2013
THE SURFACE FRONT WILL BE SOUTH OF THE FORECAST AREA MONDAY
MORNING...WITH WEAK SURFACE RIDGING ACROSS LAKE SUPERIOR. THIS WILL
HELP TO OVERALL DRY THE ATMOSPHERE...HOWEVER IT WILL ALSO ALLOW FOR
WEAK UPSLOPE FLOW IN AREAS NEAR LAKE SUPERIOR. THE NAM AND EVEN THE
GFS SUGGEST A VERY SHALLOW SATURATED LAYER BELOW 1000 FT WHICH WOULD
IMPLY AT LEAST A CHANCE FOR LOW CLOUDS AND DRIZZLE NEAR LAKE
SUPERIOR MONDAY MORNING. HOWEVER...BY AFTERNOON ANY LOW
CLOUD/DRIZZLE SHOULD MIX OUT. WILL ALSO MAINTAIN THE SLIGHT CHANCE
POPS IN THE LAKE BREEZE AREAS OF WESTERN UPPER MICHIGAN AND NEAR
LAKE MICHIGAN. ALTHOUGH THE NWP SUGGESTS A FAIRLY DRY ATMOSPHERE
BEHIND THE FRONT AND BROAD SCALE SUBSIDENCE...THE 850MB FRONT
WILL STALL OUT OVER THE AREA AND INTERIOR INSTABILITY RISES TO
NEARLY 1500 J/KG. NOT TO CONFIDENT THAT ANY SHOWERS/STORMS WILL
OCCUR MONDAY AFTERNOON...BUT ALSO NOT CONFIDENT ENOUGH TO REMOVE THE
MENTION. REGARDLESS...MONDAY WILL BE COOLER AND A LITTLE LESS HUMID
THAN TODAY WITH READINGS NEAR LAKE SUPERIOR DROPPING BACK INTO THE
LOWER-MID 70S.
MONDAY NIGHT SHOULD BE A FAIRLY QUIET NIGHT ACROSS THE AREA AS THE
NEXT LOW PRESSURE SYSTEM DEVELOPS ACROSS THE PLAINS. THE MODELS HAVE
BACKED OFF ANY PCPN FOR THE AREA MONDAY NIGHT...INSTEAD FOCUSING IT
ACROSS MN WHERE THE BETTER LOW LEVEL MOISTURE TRANSPORT AND DEEP
MOISTURE WILL BE LOCATED.
SOME DISAGREEMENT REMAINS REGARDING TIMING OF PRECIPITATION ON
TUESDAY. THERE IS A HINT FROM THE ECMWF AND GFS THAT AN MCS WILL BE
ONGOING TO WEST OF THE AREA IN THE BROAD WARM ADVECTION/ISENTROPIC
LIFT AREA IN SRN MN. THIS LEADS TO MUCH UNCERTAINTY REGARDING
CONVECTIVE EVOLUTION TUE FOR THE AREA. THE MAIN FORCING MECHANISM
TUE AND TUE NIGHT WILL CONTINUE TO BE THE NRN STREAM ENERGY DIVING
OUT OF CANADA AND AMPLIFYING DURING THE DAY...AND HAVE OPTED TO
FOCUS ON THIS FEATURE SIMILAR TO THE NAM SOLUTION. WITH THE BEST
FORCING WITH ENERGY BEING LATE TUE AFTN AND EVENING...HAVE OPTED TO
MAINTAIN THE HIGHEST POPS DURING THIS PERIOD. DEPENDING ON THE
AMOUNT OF DEBRIS CLOUDS...MODEST INSTABILITY IS POSSIBLE ACROSS THE
AREA TUE AFTN/EVENING HELPING TO MAINTAIN THUNDERSTORM DEVELOPMENT
ALONG THE FRONT. CANNOT TOTALLY RULE OUT SOME ORGANIZATION TO THE
STORMS LATER TUESDAY INTO TUESDAY EVENING AS A COUPLED UPPER JET
STRUCTURE DEVELOPS ACROSS THE NRN LAKES IN RESPONSE TO THE WAVE
BECOMING NEGATIVELY TILTED.
THE FRONT MOVES THROUGH THE AREA BY WEDNESDAY MORNING. MAY BE SOME
RESIDUAL WRAP AROUND MOISTURE ACROSS THE AREA IN THE MORNING...BUT
OTHERWISE THE WEATHER SHOULD IMPROVE DURING THE DAY. MODELS IN
EXCELLENT AGREEMENT IN SHOWING BROAD HIGH PRESSURE ACROSS THE UPPER
GREAT LAKES FOR THE END OF THE WEEK WITH RISING HEIGHTS BY THE
WEEKEND. TEMPERATURES WILL BE SEASONABLE THU AND FRIDAY ALTHOUGH
ABOVE NORMAL TEMPS MAY RETURN BY SATURDAY WITH 850MB TEMPS PROGGED
TO RISE TO +16 ACROSS THE WEST. CANNOT RULE OUT SHOWERS SATURDAY
AFTERNOON AS BOTH THE GFS AND ECMWF HINT AS AN UPPER WAVE MOVING
THROUGH THE AREA IN THE WESTERLY FLOW. HOWEVER...AT THIS TIME WILL
OPT TO MAINTAIN A DRY FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 747 AM EDT SUN JUL 7 2013
AN AREA OF SHRA/TSRA OVER WESTERN UPPER MI WILL DEPART FROM IWD AND
CMX EARLY BUT WILL IMPACT SAW THROUGH MID MORNING WITH MAINLY MVFR
CONDITIONS. DAYTIME HEATING AND MIXING WILL BRING IMPROVEMENT TO
MAINLY VFR CONDITIONS BY THIS AFTERNOON. SCT SHRA/TSRA MAY REDEVELOP
THIS AFTERNOON. CONFIDENCE IN COVERAGE/TIMING OF ANY TSTMS WAS LOW
AND NOT INCLUDED AT THIS TIME. ABUNDANT LOW LEVEL MOISTURE WILL
REMAIN IN PLACE TONIGHT AS THE MID LEVELS DRY ALLOWING FOG TO
DEVELOP OVERNIGHT WHICH MAY DROP CONDITIONS TO VLIFR NEAR AIRPORT
MINIMUMS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT SUN JUL 7 2013
GIVEN EARLY SHIP OBSERVATIONS OF ZERO VISIBILITY OVER WESTERN LAKE
SUPERIOR AND VERY HUMID AIRMASS OVER CHILLY WATER FOLLOWING SOME
SHOWERS...A DENSE FOG ADVISORY WILL REMAIN IN EFFECT THIS MORNING
FOR THE WEST HALF OF LAKE SUPERIOR. SOME DRYING ON SUNDAY
AFTERNOON FOLLOWING A COLD FRONTAL PASSAGE SHOULD DISSIPATE THE
THICKEST FOG.
WINDS WILL REMAIN BELOW 15 KT ACROSS LAKE SUPERIOR THROUGH TUESDAY
AS A WEAK SURFACE TROUGH DROPS SOUTHWARD ACROSS THE LAKE FOLLOWED BY
AN AREA OF HIGH PRESSURE. WITH SHOWERS AND THUNDERSTORMS EARLY TODAY
AND ADDITIONAL SCT SHRA/TSRA POSSIBLE THIS AFTERNOON...AREAS
OF FOG WILL CONTINUE ACROSS THE LAKE. AS ANOTHER LOW DEVELOPS OVER
THE PLAINS ON TUESDAY AND APPROACHES LAKE SUPERIOR ON
WEDNESDAY....NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL BE POSSIBLE
BEHIND FOR A TIME WEDNESDAY AND WEDNESDAY NIGHT. A SURFACE HIGH
MOVING OVER THE UPPER LAKES LATE IN THE WEEK WILL ALLOW LIGHT WINDS
TO RETURN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MZ
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 AM EDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT SUN JUL 7 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA WITH A CUTOFF MID/UPPER LEVEL LOW TO
THE SOUTH OVER IL/IN. A SHORTWAVE TROUGH COMBINED WITH UPPER LEVEL
DIV WITH THE RIGH ENTRANCE OF A 75 KNOT 250 JET OVER NRN ONTARIO...AND
FAVORABLE 925-700 THETA/E ADVECTION FROM THE UPPER MS VALLEY
SUPPORTED AN AREA OF SHRA/TSRA OVER LAKE SUPERIOR INTO W UPPER MI
AND NW WI WITH THE STRONGEST CONVECTION ON THE WRN END OF THE PCPN
AREA. AT THE SFC...A COLD FRONT HAD GRADUALLY SAGGED TO THE SOUTH INTO
NRN UPPER MI.
TODAY...EXPECT THAT WEAKENING SHRA/TSRA WILL CONTINUE TO SPREAD THROUGH
WRN INTO N CNTRL UPPER MI EARLY...PER RADAR AND SHORT RANGE MODEL
TRENDS...BEFORE THE FORCING ASSOCIATED WITH THE SHRTWV AND LOW LEVEL
INFLOW WEAKENS. BY LATE MORNING INTO THE EARLY AFTERNOON...THERE MAY
BE A LULL IN ANY PCPN BEFORE ADDITIONAL SCT SHRA/TSRA ALONG THE
FRONTAL BOUNDARY REINFORCED BY LAKE SUPERIOR BREEZE. THERE MAY BE
ENOUGH THINNING OR BREAKS IN THE CLOUD COVER FOR TEMPS TO RECOVER TO
NEAR 80...PUSHING MLCAPE VALUES INTO THE 1000-1500 J/KG RANGE.
HOWEVER...0-6KM SHEAR VALUES TO NEAR 30 KT WILL REMAIN MARGINAL FOR
STRONGER OR SEVERE ORGANIZED CONVECTION. THERE MAY STILL BE BRIEF HEAVY
RAIN AND GUSTY WINDS WITH TSRA THAT DEVELOP.
TONIGHT...AS DAYTIME HEATING SUBSIDES AND THE FRONT CONTINUES TO
PUSH TO THE SOUTH...THE REMAINING PCPN SHOULD SHIFT TO THE SOUTH AND
EAST AND DIMINISH. WITH LINGERING LOW LEVEL MOISTURE AND MID LEVEL
DRYING...AREAS OF FOG ARE EXPECTED TO DEVELOP. THERE COULD ALSO BE
SOME DRIZZLE NEAR THE WRN SHORE AS WEAK LOW LEVEL CONV DEVELOPS WITH
MOIST NE FLOW OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 505 AM EDT SUN JUL 7 2013
THE SURFACE FRONT WILL BE SOUTH OF THE FORECAST AREA MONDAY
MORNING...WITH WEAK SURFACE RIDGING ACROSS LAKE SUPERIOR. THIS WILL
HELP TO OVERALL DRY THE ATMOSPHERE...HOWEVER IT WILL ALSO ALLOW FOR
WEAK UPSLOPE FLOW IN AREAS NEAR LAKE SUPERIOR. THE NAM AND EVEN THE
GFS SUGGEST A VERY SHALLOW SATURATED LAYER BELOW 1000 FT WHICH WOULD
IMPLY AT LEAST A CHANCE FOR LOW CLOUDS AND DRIZZLE NEAR LAKE
SUPERIOR MONDAY MORNING. HOWEVER...BY AFTERNOON ANY LOW
CLOUD/DRIZZLE SHOULD MIX OUT. WILL ALSO MAINTAIN THE SLIGHT CHANCE
POPS IN THE LAKE BREEZE AREAS OF WESTERN UPPER MICHIGAN AND NEAR
LAKE MICHIGAN. ALTHOUGH THE NWP SUGGESTS A FAIRLY DRY ATMOSPHERE
BEHIND THE FRONT AND BROAD SCALE SUBSIDENCE...THE 850MB FRONT
WILL STALL OUT OVER THE AREA AND INTERIOR INSTABILITY RISES TO
NEARLY 1500 J/KG. NOT TO CONFIDENT THAT ANY SHOWERS/STORMS WILL
OCCUR MONDAY AFTERNOON...BUT ALSO NOT CONFIDENT ENOUGH TO REMOVE THE
MENTION. REGARDLESS...MONDAY WILL BE COOLER AND A LITTLE LESS HUMID
THAN TODAY WITH READINGS NEAR LAKE SUPERIOR DROPPING BACK INTO THE
LOWER-MID 70S.
MONDAY NIGHT SHOULD BE A FAIRLY QUIET NIGHT ACROSS THE AREA AS THE
NEXT LOW PRESSURE SYSTEM DEVELOPS ACROSS THE PLAINS. THE MODELS HAVE
BACKED OFF ANY PCPN FOR THE AREA MONDAY NIGHT...INSTEAD FOCUSING IT
ACROSS MN WHERE THE BETTER LOW LEVEL MOISTURE TRANSPORT AND DEEP
MOISTURE WILL BE LOCATED.
SOME DISAGREEMENT REMAINS REGARDING TIMING OF PRECIPITATION ON
TUESDAY. THERE IS A HINT FROM THE ECMWF AND GFS THAT AN MCS WILL BE
ONGOING TO WEST OF THE AREA IN THE BROAD WARM ADVECTION/ISENTROPIC
LIFT AREA IN SRN MN. THIS LEADS TO MUCH UNCERTAINTY REGARDING
CONVECTIVE EVOLUTION TUE FOR THE AREA. THE MAIN FORCING MECHANISM
TUE AND TUE NIGHT WILL CONTINUE TO BE THE NRN STREAM ENERGY DIVING
OUT OF CANADA AND AMPLIFYING DURING THE DAY...AND HAVE OPTED TO
FOCUS ON THIS FEATURE SIMILAR TO THE NAM SOLUTION. WITH THE BEST
FORCING WITH ENERGY BEING LATE TUE AFTN AND EVENING...HAVE OPTED TO
MAINTAIN THE HIGHEST POPS DURING THIS PERIOD. DEPENDING ON THE
AMOUNT OF DEBRIS CLOUDS...MODEST INSTABILITY IS POSSIBLE ACROSS THE
AREA TUE AFTN/EVENING HELPING TO MAINTAIN THUNDERSTORM DEVELOPMENT
ALONG THE FRONT. CANNOT TOTALLY RULE OUT SOME ORGANIZATION TO THE
STORMS LATER TUESDAY INTO TUESDAY EVENING AS A COUPLED UPPER JET
STRUCTURE DEVELOPS ACROSS THE NRN LAKES IN RESPONSE TO THE WAVE
BECOMING NEGATIVELY TILTED.
THE FRONT MOVES THROUGH THE AREA BY WEDNEDAY MORNING. MAY BE SOME
RESIDUAL WRAP AROUND MOISTURE ACROSS THE AREA IN THE MORNING...BUT
OTHERWISE THE WEATHER SHOULD IMPROVE DURING THE DAY. MODELS IN
EXCELLENT AGREEMENT IN SHOWING BROAD HIGH PRESSURE ACROSS THE UPPER
GREAT LAKES FOR THE END OF THE WEEK WITH RISING HEIGHTS BY THE
WEEKEND. TEMPERATURES WILL BE SEASONABLE THU AND FRIDAY ALTHOUGH
ABOVE NORMAL TEMPS MAY RETURN BY SATURDAY WITH 850MB TEMPS PROGGED
TO RISE TO +16 ACROSS THE WEST. CANNOT RULE OUT SHOWERS SATURDAY
AFTERNOON AS BOTH THE GFS AND ECMWF HINT AS AN UPPER WAVE MOVING
THROUGH THE AREA IN THE WESTERLY FLOW. HOWEVER...AT THIS TIME WILL
OPT TO MAINTAIN A DRY FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 747 AM EDT SUN JUL 7 2013
AN AREA OF SHRA/TSRA OVER WESTERN UPPER MI WILL DEPART FROM IWD AND
CMX EARLY BUT WILL IMPACT SAW THROUGH MID MORNING WITH MAINLY MVFR
CONDITIONS. DAYTIME HEATING AND MIXING WILL BRING IMPROVEMENT TO
MAINLY VFR CONDITIONS BY THIS AFTERNOON. SCT SHRA/TSRA MAY REDEVELOP
THIS AFTERNOON. CONFIDENCE IN COVERAGE/TIMING OF ANY TSTMS WAS LOW
AND NOT INCLUDED AT THIS TIME. ABUNDANT LOW LEVEL MOISTURE WILL
REMAIN IN PLACE TONIGHT AS THE MID LEVELS DRY ALLOWING FOG TO
DEVELOP OVERNIGHT WHICH MAY DROP CONDITIONS TO VLIFR NEAR AIRPORT
MINIMUMS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT SUN JUL 7 2013
GIVEN EARLY SHIP OBSERVATIONS OF ZERO VISIBILITY OVER WESTERN LAKE
SUPERIOR AND VERY HUMID AIRMASS OVER CHILLY WATER FOLLOWING SOME
SHOWERS...A DENSE FOG ADVISORY WILL REMAIN IN EFFECT THIS MORNING
FOR THE WEST HALF OF LAKE SUPERIOR. SOME DRYING ON SUNDAY
AFTERNOON FOLLOWING A COLD FRONTAL PASSAGE SHOULD DISSIPATE THE
THICKEST FOG.
WINDS WILL REMAIN BELOW 15 KT ACROSS LAKE SUPERIOR THROUGH TUESDAY
AS A WEAK SURFACE TROUGH DROPS SOUTHWARD ACROSS THE LAKE FOLLOWED BY
AN AREA OF HIGH PRESSURE. WITH SHOWERS AND THUNDERSTORMS EARLY TODAY
AND ADDITIONAL SCT SHRA/TSRA POSSIBLE THIS AFTERNOON...AREAS
OF FOG WILL CONTINUE ACROSS THE LAKE. AS ANOTHER LOW DEVELOPS OVER
THE PLAINS ON TUESDAY AND APPROACHES LAKE SUPERIOR ON
WEDNESDAY....NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL BE POSSIBLE
BEHIND FOR A TIME WEDNESDAY AND WEDNESDAY NIGHT. A SURFACE HIGH
MOVING OVER THE UPPER LAKES LATE IN THE WEEK WILL ALLOW LIGHT WINDS
TO RETURN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
634 AM CDT SUN JUL 7 2013
.UPDATE...
12Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CDT SUN JUL 7 2013
A COUPLE OF WEAK BOUNDARIES OF CONCERN TO START THE DAY. ONE IS A
TROUGH/COLD FRONT THAT AT 3 AM WAS ALONG THE ND/MN DOWN TO A WEAK
LOW OVER NE SODAK...EXTENDING BACK SW INTO CENTRAL NEB. OTHER
BOUNDARY IS A STATIONARY FRONT EXTENDING FROM AROUND MORRIS ACROSS
CENTRAL MN INTO THE HAYWARD AREA. LLJ AND WAA REGIME NORTH OF THE
STATIONARY BOUNDARY HAS GENERATED A CLUSTER OF STORMS OVER LAKE
SUPERIOR THAT HAVE STAYED SAFELY AWAY FROM THE MPX AREA OVERNIGHT.
FOR TODAY...THIS STATIONARY BOUNDARY WILL START TO LOOSE ITS
DEFINITION AS IT SLOWLY SAGS SE. MOST DETERMINISTIC MODELS SAY TODAY
WILL BE DRY AS GRADUAL HEIGHT RISES OVERTAKE THE AREA.
HOWEVER...THE ZONAL FLOW OVER THE REGION TODAY LOOKS TO BE OF THE
DIRTY VARIETY...WITH THE RAP/GFS/NAM SHOWING SMALL PERTURBATIONS
CURRENTLY GENERATING STORMS OUT OVER MT/WY WORKING ACROSS MN DURING
THE LATE AFTERNOON/EARLY EVENING. 07.00 NAM SOUNDINGS SHOW A RATHER
UNSTABLE ENVIRONMENT BEING IN PLACE AS THESE WAVES APPROACH...WITH
2000-3000+ J/KG OF UNCAPPED SBCAPE BEING IN PLACE. AT THE SAME
TIME...RAP SOUNDINGS ONLY ABLE TO GENERATE 1500 J/KG AT BEST.
700-500 MB LAPSE RATES ARE MEAGER ON BOTH /ABOUT 6 DEG C PER
KM/...WITH THE DIFFERENCE COMING WITH HANDLING OF LOW LEVEL
MOISTURE...AS THE RAP LOOKS A LITTLE AGGRESSIVE ON MIXING OUT DEWPS
THIS AFTERNOON...WHICH IN TURN IS IMPACTING ITS INSTABILITY
FORECAST. NAM IDEA IS PROBABLY MORE REALISTIC...BUT GIVEN MID-LEVEL
LAPSE RATES...WOULD FAVOR 1500-2500 J/KG OF CAPE TO WORK WITH TODAY.
WITH ALL THAT SAID...AT THE MOMENT ONLY HAVE CHANCE POPS MENTIONED
IN THE FAR ERN CWA THIS AFTERNOON AS THIS IS WHERE SOME FORM OF LLJ
FORCING LOOKS TO RESIDE...BUT GIVEN THE INSTABILITY MENTIONED
ABOVE...COULD SEE STORMS DEVELOP ANYWHERE ALONG/SOUTH OF THE
STATIONARY BOUNDARY. 03Z HOPWRF ENSEMBLE REFLECTIVITY FORECASTS HINT
AT THIS HAPPENING...WITH SCATTERED CONVECTION SEEN AT 21Z ON MEMBERS
1/3/4 ACROSS MOST OF THE AREA. GUESS AT THIS POINT...THIS "WET
PATTERN" THAT SET IN FRIDAY NIGHT HAS NOT EXACTLY PRODUCED MUCH IN
THE WAY OF OBSERVABLE PRECIPITATION IN THE MPX AREA...SO AM A BIT
GUN SHY ON GOING TO HIGH WITH POPS AT THIS POINT. WITH LOW LEVEL
FLOW BACKING OFF CONSIDERABLY TODAY...LOW LEVEL SHEAR WILL BE PRETTY
WEAK TODAY...BUT WITH INVERTED V SOUNDINGS SEEN IN MODELS...A
CONDITIONAL WIND THREAT WOULD EXIST.
FOR TONIGHT...LLJ FORCING AND THICKNESS PATTERN CONTINUE TO SHOW THE
MPX AREA SPLIT BETWEEN BETTER REGIONS OF FORCING FOR CONVECTION OVER
NRN IL/SRN WI AND OUT WEST ACROSS THE DAKOTAS...SO EXPECT TONIGHT TO
BE DRY ONCE ANY DIURNALLY DRIVEN ACTIVITY DISSIPATES THIS EVENING.
FOR TEMPERATURES...DENSE MID LEVEL CLOUD COVER SHOULD CLEAR ERN
AREAS FAIRLY QUICKLY THIS MORNING...WITH A FAIR AMOUNT OF SUNSHINE
EXPECTED AS A RESULT. AIRMASS HAS CHANGED VERY LITTLE SINCE
YESTERDAY...SO EXPECT HIGHS TO BE VERY SIMILAR TO WHAT WAS SEEN
OUTSIDE OF CENTRAL MINNESOTA ON SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 409 AM CDT SUN JUL 7 2013
MAIN CHALLENGE IS TRYING TO PINPOINT THE TIMING AND PLACEMENT OF
POPS EARLY IN THE WEEK BEFORE WE DRY OUT WEDNESDAY THROUGH FRIDAY.
THE UPPER LEVEL RIDGE ANCHORED OVER THE DESERT SOUTHWEST WILL
REMAIN THROUGHOUT THE PERIOD. MONDAY SHOULD START OUT DRY AS THE
LOW LEVEL JET AS SEEN IN THE H925 WINDS AND MOISTURE TRANSPORT
WILL REMAIN WELL SOUTH OF THE FORECAST AREA IN SOUTHERN
IOWA/ILLINOIS. THE HUMID AIRMASS WILL PERSIST ACROSS THE UPPER
MIDWEST...AND WITH LITTLE MIXING EXPECTED ON MONDAY HAVE INCREASED
DEWPOINTS INTO THE LOW 70S. BY MONDAY EVENING FORECAST MODELS
INDICATE A SUBTLE H500 SHORTWAVE ROTATING AROUND THE PERIPHERY OF
THE AFOREMENTIONED MONSOON RIDGE AND THIS SHOULD TRIGGER OFF SOME
DEEP CONVECTION ON THE LEE SIDE OF THE ROCKIES WHICH WILL ADVECT
EASTWARD OVER THE HIGH PLAINS OF THE DAKOTAS...AND COULD REACH THE
CWA LATER MONDAY NIGHT INTO EARLY TUESDAY MORNING. THE 07.12 GFS
AND ECMWF PLACE THE NOSE OF THE LOW LEVEL JET IN A FAVORABLE
LOCATION FOR CONVECTION OVER THE MISSISSIPPI RIVER VALLEY.
CURRENTLY HAVE THE HIGHEST POPS ALONG I90 NEAR THE IA BORDER...BUT
THESE MAY NEED TO BE ADJUSTED NORTHWARD IF THE MODELS FOLLOW THE
LEAD OF THE ECMWF...WHICH TAKES THE MCS ALONG AND NORTH OF I94.
THERE WILL BE PLENTY OF INSTABILITY AS SREF PLUMES KEEP AROUND
1000 J/KG OF MUCAPE ACROSS THE REGION MONDAY NIGHT...WITH ROUGHLY
30KTS OF DEEP LAYER SHEAR DEPENDING ON THE PLACEMENT OF THE LLJ.
THE FORECAST FOR TUESDAY BECOMES DIFFICULT SINCE MANY OF THE DETAILS
HINGES DIRECTLY ON THE MESOSCALE FEATURES LEFT IN THE WAKE OF THE
EARLY MORNING CONVECTION. A MORE WELL-DEFINED SHORTWAVE CURRENTLY
OFF THE MOVING DOWN THE COAST OF BRITISH COLUMBIA WILL TRANSLATE
EASTWARD IN THE ZONAL FLOW ALONG THE INTERNATIONAL BORDER AND ARRIVE
ACROSS THE UPPER MIDWEST TUESDAY AFTERNOON. THIS WILL DRIVE A COLD
FRONT THROUGH THE REGION ON TUESDAY...HOWEVER EXPECT ANY REMNANT
DEBRIS CLOUDS TO CLEAR OFF ALLOWING THE BOUNDARY LAYER TO RECOVER
DURING THE LATE MORNING HOURS...WITH AN UNSTABLE ENVIRONMENT SETTING
UP ACROSS THE MN/WI BORDER BY TUESDAY AFTERNOON. AN H500 SPEED MAX
OF 60KTS...ALONG WITH 3M/HR HEIGHT FALLS WILL PROVIDE SYNOPTIC SCALE
FORCING FOR SEVERE THUNDERSTORMS AHEAD OF THE COLD FRONT. AS ALLUDED
TO IN THE SPC DAY3 OUTLOOK...ANY OUTFLOW BOUNDARY PRODUCED BY THE
EARLY MORNING CONVECTION WILL BE THE FOCUS FOR AN ENHANCED THREAT OF
SEVERE WEATHER...INCLUDING TORNADOES AS THE SURFACE WINDS BACK AHEAD
OF THE COLD FRONT. NAM BUFR SOUNDINGS FOR TUESDAY AFTERNOON AT KRWF
SHOW A CYCLONICALLY CURVED HODOGRAPH WITH 0-3KM HELICITY OF OVER
300M2/S2. THE GFS IS FASTER WITH THE COLD FRONT...SO ITS LINEAR
SHEAR PROFILE WITH NORTHWEST WIND IS LESS FAVORABLE FOR
TORNADOES...BUT RATHER WOULD SUPPORT STRAIGHT LINE WINDS.
REGARDLESS...TUESDAY SEVERE THREAT LOOKS TO BE THE MAIN CONCERN
DURING THE EXTENDED.
NORTHWEST FLOW IN THE WAKE OF THIS COLD FRONT WILL USHER IN DRIER
AIR AS A CANADIAN HIGH PRESSURE BUILDS ON WEDNESDAY AND KEEPS THE
REGION DRY THROUGH FRIDAY. HAVE INCREASED WINDS SLIGHTLY ABOVE
GUIDANCE ON WEDNESDAY AS FORECAST SOUNDINGS SHOW ANOTHER GOOD MIXING
DAY. LOOKING AHEAD...THE REPRIEVE FROM THE HEAT AND HUMIDITY WILL BE
SHORTLIVED AS THE THERMAL RIDGE DEVELOPS BY THE END OF THE WORK WEEK
ACROSS THE HIGH PLAINS. WILL ACTUALLY SEE A WEST/EAST TEMPERATURE
GRADIENT BY THE WEEKEND...WITH MUCH WARMER TEMPERATURES ACROSS
WESTERN MINNESOTA. CURRENTLY HAVE MORE OF A BLENDED APPROACH WHICH
YIELDS ONLY MID 80S ACROSS THE WEST. THERE IS STILL
UNCERTAINTY...BUT IF THE H850 TEMPS REMAIN 20-22C WILL LIKELY SEE
HIGHS IN THE MID 90S NEAR THE MN/SD BORDER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CDT SUN JUL 7 2013
AFTER ALMOST THE ENTIRE NIGHT...SHOWERS HAVE FINALLY STARTED
BUILDING DOWN THE LLJ INTO WRN WI. THEY WILL BE FAST MOVING THOUGH
AND OUT OF THE EAU AREA BY 14Z. AFTER THAT...WILL BE WAITING UNTIL
ABOUT 22Z FOR WHEN NEXT CHANCE FOR TSRA DEVELOPS. CERTAINLY THE
NAM WOULD CONTINUE TO LEAVE ONE TO BELIEVE AN AREA OF SCT STORMS
COULD DEVELOP IN THE STC/MSP AREA THIS AFTERNOON...BUT CONFIDENCE
NOT VERY HIGH IN THIS OCCURRING AT THE MOMENT AS MODELS HAVE BEEN
A LITTLE OVER EXUBERANT IN GENERATING CONVECTION THE LAST COUPLE OF
DAYS. TONIGHT WILL SEE SIMILAR CONDITIONS TO WHAT WAS SEEN LAST
NIGHT OVER CENTRAL MN: CALM WINDS...MAINLY CLEAR SKIES...AND DEWPS
UP AROUND 70. AS A RESULT...LAMP IS PRETTY AGGRESSIVE WITH
KNOCKING VIS DOWN LATE SUNDAY NIGHT. HOWEVER...THIS MORNING WHERE
DENSE FOG FORMED...HIGHS YESTERDAY WERE ONLY IN THE 70S...EXPECT
UPPER 80S TO LOWER 90S EVERYWHERE TODAY...WHICH SHOULD LIMIT THE
FG POTENTIAL TONIGHT TO MVFR...IFR AT WORSE.
KMSP...OUTSIDE OF A SMALL CHANCE FOR TSRA BETWEEN ABOUT 22Z AND
02Z...THIS TAF PERIOD LOOKS DRY WITH VERY LIGHT WINDS. WITH CLEAR
SKIES AND HIGH DEWP AIR IN PLACE...SHOULD START OF MONDAY MORNING
QUITE HAZY...WITH POSSIBLY SOME FOG DOWN IN THE RIVER VALLEY...BUT
THAT SHOULD BE IT FOR POTENTIAL RESTRICTIONS.
/OUTLOOK FOR KMSP/
MON...MVFR VIS POSSIBLE EARLY. CHC TSRA LATE NIGHT. WINDS E 5 KTS.
TUE...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE BCMG NW AT 5 KTS.
WED...VFR. WINDS NW 10G20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 AM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT SUN JUL 7 2013
IF MOISTURE CAN REMAIN IN PLACE THIS MORNING THEN ANOTHER ROUND OF
THUNDERSTORMS COULD DEVELOP THIS AFTERNOON AND TONIGHT. THE
DISTURBANCE AND ONGOING STORM ACTIVITY ACROSS WESTERN NEB SHOULD
EXIT THE FCST AREA TO EAST BY 20Z. THIS IMPLIES THAT THE STORMS
WEAKEN AND FALL APART AS THEY MOVE EAST AS INDICATED BY THE HRRR.
DEEP EASTERLIES SHOULD CONTINUE TODAY AS INDICATED BY THE VWP AT
KUDX AND THIS WOULD SUPPORT DESTABILIZATION ACROSS WESTERN NEB LATE
THIS MORNING THROUGH THIS EVENING WHICH IN TURN WOULD PROPAGATE EAST
THROUGH THE FCST AREA. THE FCST MIGHT BE AMBITIOUS WITH THE 40 POPS
BUT THIS IS A MARK DOWN FROM A 5 MODEL BLEND OF THE
ECM...GFS...SREF...NAM AND GEMREG. WATER VAPOR SUGGESTS ANOTHER
DISTURBANCE ACROSS WRN WY AND NRN UT WHICH COULD COME ACROSS THIS
AFTERNOON ON THE HEALS OF THE ONGOING DISTURBANCE.
MODEST DEEP LAYER SHEAR UP TO 250 MB WOULD PERHAPS SUPPORT ISOLATED
SEVERE STORMS WHICH WOULD PROBABLY PULSE SEVERE FROM TIME TO TIME
THIS AFTERNOON AND THIS EVENING. THE WEAKNESS IN THE LOW LEVEL WINDS
SUGGESTS THIS BEHAVIOR. SPC SUGGESTED A WEAKLY ORGANIZED MCS MIGHT
DEVELOP AND THIS CERTAINLY APPEARS IN LINE WITH THE 21Z OUTPUT OF
THE 06Z HRRR SHOWING A FAIRLY ORGANIZED LINE OF STORMS FROM KOGA TO
KVTN.
HIGHS IN THE UPPER 80S TO MID 90S ARE EXPECTED TODAY. THE MODELS
HAVE COME IN A FEW DEGREES COOLER FOR HIGHS TODAY VERSUS SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 311 AM CDT SUN JUL 7 2013
ACTIVE FIRST HALF OF THE WEEK EXPECTED...AS THE AREA REMAINS ON
THE NORTHERN SIDE OF LARGE RIDGE OF UPPER HIGH PRESSURE CENTERED
ACROSS THE FOUR CORNERS REGION. WINDS ALOFT...MOISTURE...AND
INSTABILITY WILL BE FAVORABLE FOR TSTMS UNTIL THE RIDGE BEGINS TO
BUILD NORTH OVER THE AREA BY WEEKS END. TEMPERATURES ALOFT WILL
WARM THEN AS WELL AS A DECREASE IN WINDS ALOFT...CONDITIONS LESS
FAVORABLE FOR TSTM DEVELOPMENT.
A STATIONARY FRONT WILL OSCILLATE NORTH AND SOUTH THE FIRST HALF
OF THE WEEK...AND WILL BE A FOCUS FOR STORM DEVELOPMENT. OTHER
STORMS MAY FORM OFF THE HIGHER TERRAIN TO OUR WEST AND MOVE EAST
INTO THE AREA DURING THE EVENING HOURS. PWATS WILL BE RATHER
HIGH...WITH PLENTY OF LOW LEVEL MOISTURE IN PLACE TOO...SO SOME
DECENT RAINFALL TOTALS ARE POSSIBLE.
TEMPERATURES WILL BE WARM...AND THEN TURNING HOT BY WEEKS END AS
THE RIDGE BUILDS NORTH OVER THE AREA. HIGHS IN THE UPPER 80S TO
MID 90S WILL START THE WEEK...WITH MID 90S TO AROUND 100 TO FINISH
THE WEEK. DEPENDING ON DEW POINTS...WHICH CURRENTLY LOOK TO REMAIN
HIGH EAST OF HIGHWAY 83 AS THE HEAT BUILDS IN BY THE END OF THE
WEEK...WE COULD BE FLIRTING WITH HEAT ADVISORY CONDITIONS. WILL
CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 620 AM CDT SUN JUL 7 2013
VFR IS EXPECTED THROUGH 18Z MOST AREAS. THEREAFTER...THE MODEL
CONSENSUS SUGGESTS SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS AN
INCREASINGLY LARGER PORTION OF THE FCST AREA AND SPREAD EAST
THROUGH SUNDAY NIGHT.
STORM ACTIVITY ACROSS NORTHWEST NEBRASKA SHOULD CONTINUE THIS
MORNING WITH VFR ELSEWHERE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1012 AM EDT SUN JUL 7 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EAST COAST COMBINED WITH A MID LEVEL
LOW OVER THE OHIO VALLEY WILL KEEP A SOUTHERLY FLOW OF WARM AND VERY
MOIST AIR THROUGH THE REMAINDER OF THE WEEKEND WITH SCATTERED
SHOWERS AND THUNDERSTORMS...ESPECIALLY INLAND FROM THE LAKES. THE
UNSETTLED WEATHER WILL CONTINUE THROUGH THE MIDDLE OF NEXT WEEK
BEFORE DRIER AIR FINALLY ARRIVES BY THE END OF THE WEEK AS HIGH
PRESSURE BUILDS INTO THE GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR LOOP SHOWS A COMPLEX OF SHOWERS ASSOCIATED WITH A MID-LEVEL
SHORTWAVE EXITING TO THE EAST LATE THIS MORNING. AS THIS
EXITS...THERE WILL LIKELY BE SOME DRYING IN ITS WAKE AS 700 MB
WINDS DIMINISH WHICH PROMOTE MID-LEVEL DIVERGENCE. THE MAJORITY OF MODEL
GUIDANCE DID NOT CAPTURE THIS FEATURE...AND AS SUCH PROBABLY WILL NOT
CAPTURE THE SUBSIDENCE IN PLACE BEHIND THE EXITING WAVE. THE 06Z
GFS AND HRRR DID CAPTURE THIS FEATURE...AND AS A RESULT WILL BE
HEAVILY WEIGHTED FOR TODAY/S FORECAST.
FOR THE REMAINDER OF TODAY...THERE MAY BE A FEW LINGERING SHOWERS
EAST OF LAKE ONTARIO IN ASSOCIATION WITH WEAK WARM ADVECTION THROUGH
LATE MORNING. OTHERWISE THIS MORNING SHOULD BE DRY. DAYTIME
HEATING WILL RESULT IN INCREASING INSTABILITY TODAY. FOLLOWING THE
GFS/HRRR GUIDANCE WHICH IS FAIRLY WELL ALIGNED WITH LATEST WATER
VAPOR IMAGERY...EXPECT THE LARGE SCALE AND/OR ORGANIZED CONVECTION
TO TRACK TO OUR SOUTH AND EAST THIS AFTERNOON. THIS WILL AGAIN
LEAVE MORE SUBTLE MESOSCALE FEATURES WHICH PROVIDE THE FOCUS FOR
CONVECTION FOR OUR AREA THIS AFTERNOON.
WITH THE ABOVE IN MIND...HAVE GONE WITH SCATTERED SHOWERS AND
ISOLATED THUNDER AGAIN FOR THE AFTERNOON FROM THE WESTERN SOUTHERN
TIER INTO THE FINGER LAKES. FARTHER NORTH...EXPECT MOST OF THE
NIAGARA FRONTIER EAST TO ROCHESTER TO REMAIN DRY GIVEN THE
DEVELOPING LAKE SHADOW AND LESS DEEP LAYER MOISTURE. IT WILL BE
ANOTHER WARM AND VERY MUGGY DAY WITH LOWER ELEVATIONS AWAY FROM LAKE
INFLUENCES REACHING THE MID 80S...WITH SOME SPOTS IN CENTRAL NY
REACHING THE UPPER 80S. THE HIGHER TERRAIN...NORTH COUNTRY...AND
LAKESHORES WILL BE A LITTLE COOLER...BUT STILL VERY MUGGY.
FROM A SYNOPTIC STANDPOINT...THE BERMUDA HIGH WILL REMAIN IN PLACE
FOR THE NEXT 24 HOURS AND BEYOND AS THE CUTOFF LOW OVER THE WESTERN
OHIO VALLEY ACCELERATES EAST AND REACHES WESTERN PA BY DAYBREAK
MONDAY AS IT RE-ENGAGES WITH THE WESTERLIES. THIS CUTOFF...AND THE
ASSOCIATED MID LEVEL TROUGH WILL BECOME THE MAIN FORECAST PLAYER
LATER TONIGHT.
THIS EVENING THE SHOWERS FROM THE WESTERN SOUTHERN TIER INTO CENTRAL
NY WILL SLOWLY DIMINISH AND PUSH EAST WITH THE LOSS OF DAYTIME
HEATING AND PASSAGE OF THE SUPPORTING SHORTWAVE. THE MAIN MID LEVEL
LOW WILL MAKE PROGRESS OVERNIGHT...REACHING WESTERN PA BY DAYBREAK
MONDAY. THE APPROACH OF THE MID LEVEL TROUGH WILL BRING AN INCREASE
IN LARGE SCALE ASCENT OVERNIGHT...AND A 900-700MB TROUGH DROPPING
SOUTHEAST OUT OF CANADA WILL LIKELY PROVIDE CONVERGENCE AND FOCUS
FOR A DEVELOPING AREA OF SHOWERS AND SCATTERED STORMS LATE TONIGHT.
WITH THIS IN MIND...HAVE RAMPED UP POPS TO LIKELY BY LATE TONIGHT
WITH THE APPROACH OF THIS FEATURE. IT WILL BE ANOTHER MUGGY NIGHT
WITH LOWS AROUND 70 ON THE LAKE PLAINS AND MID TO UPPER 60S FARTHER
INLAND.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
THE UPPER THROUGH WHICH HAS BEEN IN PLACE OVER THE MIDWESTERN STATES
WILL CONTINUE TO MOVE SLOWLY TO THE EAST AND TRACK ACROSS NEW YORK
STATE AND PA ON MONDAY. THE LIFT ASSOCIATED WITH THE SHORT WAVE
TROUGH WILL HAVE THE GREATEST IMPACT ON OUR AREA MONDAY
MORNING...BEFORE IT SHIFTS INTO EASTERN NEW YORK STATE AND NEW
ENGLAND DURING THE AFTERNOON. A WEAK WAVE THAT WILL BE TRACKING EAST
ACROSS A FRONT...STALLED JUST TO OUR NORTH...WILL GENERATE
ADDITIONAL LIFT AND WILL HELP TO FOCUS THE ABUNDANT LOW LEVEL
MOISTURE THAT STILL WILL BE IN PLACE. BASED ON THESE TRENDS...EXPECT
A HIGH LIKELIHOOD OF SHOWERS AND SCATTERED THUNDERSTORMS MONDAY
MORNING. AS THE PRIMARY SOURCES OF LIFT SHIFT TO OUR EAST DURING THE
AFTERNOON...WE SHOULD SEE A WEST TO EAST DECREASE IN PCPN.
WITH PRECIPITABLE WATER VALUES FORECAST TO RANGE FROM 1.5 INCH TO
1.75 INCH...ANY CONVECTION MAY PRODUCE HEAVY RAIN...BUT THERE SHOULD
BE SUFFICIENT DIRECTIONAL SHEAR TO KEEP CELLS FROM TRAINING OVER THE
SAME SMALL AREAS ALONG THE STORM TRACKS... LIMITING THE FLOOD THREAT.
AS THE UPPER SHORT WAVE TROUGH CONTINUES TO MOVE TO THE EAST MONDAY
NIGHT...WEAK RIDGING SHOULD PROVIDE US WITH MAINLY DRY WEATHER. HIGH
PRESSURE WILL REMAIN IN CONTROL FOR MOST OF TUESDAY...BUT LATE DAY
SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE FAR WEST AS A WARM
FRONT AND SHORT WAVE MOVE EAST TOWARD THE LOWER LAKES.
INCREASING MOISTURE (PWATS FORECAST TO RISE TO ABOUT 2 INCHES)
AHEAD OF THE WARM FRONT AND ADDED LIFT IN THE VICINITY OF THE SHORT
WAVE TROUGH WILL BRING A GOOD CHANCE FOR SHOWERS AND THUNDERSTORMS
TUESDAY NIGHT AND WEDNESDAY. UNSETTLED WEATHER WILL CONTINUE
WEDNESDAY NIGHT AS A COLD FRONT...TRAILING SOUTH OF LOW PRESSURE
NEAR JAMES BAY...PUSHES EAST ACROSS THE STATE.
TEMPERATURES ON MONDAY WILL BE CLOSE TO SEASONAL AVERAGES. WARMER
TEMPERATURES RETURN ON TUESDAY AND WEDNESDAY...ALONG WITH AN
INCREASE IN HUMIDITY...ESPECIALLY ON WEDNESDAY.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
A TRANSITION TO A HIGHER AMPLITUDE PATTERN ALOFT WILL TAKE PLACE
DURING THIS PERIOD...CHARACTERIZED BY A DIGGING TROUGH OVER THE
GREAT LAKES WHILE A RIDGE BUILDS OUT WEST. THIS PATTERN SHIFT WILL
RESULT IN A TREND TOWARD SLIGHTLY COOLER TEMPERATURES AND LOWER
HUMIDITY AS THE WEEK PROGRESSES.
AT THE SURFACE...THE COLD FRONT THAT WILL BE PUSHING EAST ACROSS THE
AREA WEDNESDAY NIGHT WILL REACH THE EAST COAST ON THURSDAY. WHILE
DRIER AIR WILL WORK IN BEHIND THE FRONT...COOLER AIR ASSOCIATED WITH
THE DEEPENING UPPER LEVEL TROUGH MAY GENERATE ENOUGH INSTABILITY FOR
A FEW MORE SHOWERS.
THE LATEST GUIDANCE NOW SUGGESTS THAT THE UPPER LEVEL TROUGH WILL
CUTOFF AND SETTLE OVER THE OHIO VALLEY AND LOWER LAKES FRIDAY AND
SATURDAY. AT THE SAME TIME...HIGH PRESSURE AT THE SURFACE IS
FORECAST TO BUILD EAST ACROSS THE GREAT LAKES. WHILE THE TROUGH MAY
ENHANCE INSTABILITY...THIS SYSTEM MAY BE STARVED FOR MOISTURE.
THEREFORE...WILL MAINTAIN ONLY LOW CHANCE OR SLIGHT CHANCE POPS FOR
FRIDAY AND SATURDAY. MOST OF THE RESULTANT RAIN FROM THIS WILL BE
ASSOCIATED WITH AN OFFSHORE COASTAL SYSTEM.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AN AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WHICH CROSSED
THE AREA DURING THE WEE HOURS OF THE MORNING IS RACING EAST INTO
EASTERN NY AND WEAKENING THIS MORNING. A FEW LEFTOVER MAINLY LIGHT
SHOWERS WILL CONTINUE ACROSS THE SAINT LAWRENCE VALLEY THROUGH LATE
MORNING...OTHERWISE THE REST OF THE AREA WILL REMAIN DRY. MOSTLY VFR
CONDITIONS WILL PREVAIL...ALTHOUGH A FEW PATCHES OF MVFR CIGS NEAR
KBUF-KIAG WILL PERSIST THROUGH MID MORNING.
ANOTHER MID LEVEL DISTURBANCE AND PLUME OF MOISTURE IS FORECAST TO
CROSS THE WESTERN SOUTHERN TIER AND FINGER LAKES LATER IN THE
AFTERNOON AND EARLY EVENING...AND THIS MAY PRODUCE ADDITIONAL
SCATTERED SHOWERS AND ISOLATED STORMS INCLUDING KJHW. CONDITIONS
WILL BE VFR MOST OF THE TIME...BUT ANY SHOWER OR THUNDERSTORM WILL
BRIEFLY DIP CIGS/VSBY TO MVFR/IFR. A SOUTHWEST FLOW OFF LAKES ERIE
AND ONTARIO SHOULD AID IN STABILIZING THE ATMOSPHERE ENOUGH TO KEEP
THE RISK OF SHOWERS LOW AT THE REST OF THE TAF SITES.
THIS EVENING ANY SHOWERS ACROSS THE SOUTHERN TIER AND FINGER LAKES
WILL WEAKEN. LATE TONIGHT YET ANOTHER MID LEVEL TROUGH WILL APPROACH
THE REGION AND TOUCH OFF MORE SHOWERS AND A FEW THUNDERSTORMS. AGAIN
MOST OF THE NIGHT SHOULD BE VFR...BUT BRIEF MVFR/IFR IS POSSIBLE IN
ANY OF THE HEAVIER SHOWERS.
OUTLOOK...
MONDAY THROUGH WEDNESDAY...MAINLY VFR WITH SCATTERED SHOWERS AND
THUNDERSTORMS AND ASSOCIATED BRIEF MVFR/IFR CONDITIONS.
THURSDAY...VFR.
&&
.MARINE...
SOUTHWEST WINDS WILL INCREASE SOME TODAY...ESPECIALLY ON LAKE ERIE
WHERE THE SOUTHWEST FLOW WILL CHANNEL UP THE LAKE. THIS WILL PRODUCE
CHOPPY WAVES IN THE 2-4 FOOT RANGE. FOR NOW WILL KEEP CONDITIONS
JUST BELOW SMALL CRAFT ADVISORY CRITERIA BUT THIS WILL NEED TO BE
MONITORED. LIGHT TO MODERATE SOUTHWEST WINDS WILL CONTINUE TONIGHT
THROUGH MONDAY WITH CHOPPY WAVE ACTION AT TIMES ON BOTH LAKE...BUT
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...TJP
LONG TERM...TJP
AVIATION...HITCHCOCK
MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
854 AM EDT SUN JUL 7 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST OVER THE REGION THROUGH
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY DURING
THE AFTERNOON. SINCE THE AIRMASS REMAINS VERY MOIST ANY
THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL. THE UPPER
LEVEL TROUGH WILL EXIT THE NORTHEASTERN UNITED STATES MONDAY NIGHT
BRINGING A BRIEF END TO THE RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
845 AM UPDATE...
EARLY MRNG MCS HAS MOVD EAST AND IS ENTERING WRN NEW
ENGLAND...WITH FCST AREA UNDER PC SKIES. TDA`S SCENARIO IS NOT
MUCH DIFFERENT FROM PREV DAYS. UPR LOW OVER INDIANA THIS MRNG
WITH S/WV`S ROTATING NEWD FROM THE ERN OH VLY INTO THE NE U.S..
NXT S/WV IS OVER WRN WV WHICH WILL BE HEADING NEWD TWDS WRN NY LATE
TDA. OTHER THAN THIS FEATURE...THERE IS NOT MUCH TO FOCUS
CONVECTIVE DVLPMNT TDA OTHER THAN ANY MESO-BETA BNDRYS AND TRRN
FEATURES.
IN THE NEAR TERM WE LOWERED POPS INTO EARLY AFTN AND REMOVED ANY
QPF BEFORE 18Z...THEN CHC POPS THIS AFTN FOR SCT SHRA/TSRA. WIND
SHEAR TDA IS MARGINAL FOR ORGANIZED STORMS AND IS ACTUALLY LOWERING
THIS MRNG INTO EARLY AFTN...BUT INCREASES TO MARGINALLLY
SUPPORTIVE VALUES ACRS WRN ZONES LATE TDA WITH APRCH OF NXT S/WV.
GIVEN MOIST CONDITIONS...LCL +RA WILL BE MAIN THREAT WITH ANY
STORMS TDA. PREV BLO...
630 AM UPDATE...
JUST DID ANOTHER MAJOR RE-WORK OF THE POPS GRIDS AS S/WV IS
EXITING STAGE RIGHT AT THIS TIME, TAKING THE STORMS WITH IT IN THE
NEXT HR. BASED ON LATEST RUC FCST AND CURRENT TRENDS NOT EXPECTING
MUCH IN THE WAY OF SHOWERS TO GET IN HERE BFR 15Z AND ONLY SCTD,
AT BEST, AFTER THAT TIME.
520 AM UPDATE...
QUICK UPDATE TO UP POPS ACRS UPSTATE NY TO 50% FOR CLUSTER OF
TSTMS MVG THRU NRN ZONES. ALSO UPPED QPF TO AROUND 0.25 INCHES
BASIN-AVERAGE THRU 12Z THO LOCALLY HIGHER AMNTS MAY EXIST.
330 AM UPDATE...
BERMUDA RIDGE CONTS TO SPIN OFF THE ATLANTIC COAST WITH PLENTIFUL
MOISTURE BEING PUMPED INTO CWA FM GOM. UL TROF/LOW IS ON THE MV AS
RIDGE IS WEAKENING. S/WV LOCATED ACRS OH/KY AREA WL APPCH THE FA
THIS AFTN AND RESULT IN A GOOD CHC FOR SHRA/TSRA ACTIVITY. THUS WL
GO WITH LKLY POPS ACRS WRN ZONES ARND 18Z OR SO THEN DIMINISHING AFT
THAT AS WV PASSES OFF TO THE WEST AND MID-LVL LAPSE RATES WEAKEN.
AS FOR SVR POTENTIAL, EXPECT ONLY A STRONG STORM OR TWO AS 0-6KM
BULK SHEAR VALUES WEAKEN THRU THE DAY. ANY TSTM THAT CAN DVLP WL HV
THE POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS AND LOCALIZED FLOODING
AND THIS WL LKLY BE THE MAIN THREAT FOR THIS AFTN.
H8 TEMPS TO ARND 17C TDA WL YIELD HIGHS IN THE M/U 80S SIMILAR TO
YDA.
FOR TONIGHT, UL LOW WL OPEN UP ACRS NRN OHIO BY 06Z AND BEGIN TO
EJECT EAST WITH SCTD THUNDER RMNG ACRS THE REGION THRU 12Z MONDAY.
EXPECTING OVRNGT MINS TO RMN UP IN THE U60S WITH DWPTS RMNG JUST A
DEGREE OR TWO LOWER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
330 AM UPDATE...
UPR TROF WL BE EJECTING OUT DRG THE DAY ON MONDAY WITH PW VALUES
GRADUALLY DROPPING THRU THE AFTN. POTENTIAL EXISTS FOR LCLY HVYR
RAINFALL THRU THE COURSE OF THE DAY WITH UL TROF INTERACTING WITH
FRONTAL BNDRY ACRS THE NERN U.S. THIS, IN ADDITION TO SATURATED SOIL
CONDS WL BRING A HEIGHTENED THREAT FOR FLOODING ON MONDAY. THUS, WL
HIGHLIGHT THREAT IN THE HWO.
PCPN SHUD GRADUALLY WIND DOWN MON NGT AS FLOW TRANSITIONS TO A MORE
ZONAL FLOW ALOFT. DIURNAL CONVECTION WL ONCE AGAIN BE POSSIBLE TUE
AFTN BFR TAPERING OFF TUE NGT, AHD OF NEXT H5 TROF HEADED IN FM THE
WEST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FAIRLY ACTIVE WX PATTERN EXPECTED TO PERSIST RIGHT THROUGH THE
CONCLUSION OF THE LONG TERM PERIOD AS A STRONG COLD FRONT PASSES
THROUGH THE AREA ON EARLY THURSDAY...FOLLOWED BY A AN UPPER
CLOSED LOW STALLING OVER THE TENNESSEE VALLEY BY WEEK/S END.
MODELS REMAIN IN EXCELLENT AGREEMENT ON THE TIMING OF THE
AFOREMENTIONED COLD FRONT WITH THE GFS...ECMWF AND CANADIAN-CMC
SOLUTIONS ALL FAVORING AN LATE WED/EARLY THU MORNING PASSAGE. FROM
THIS VANTAGE POINT...THE SLIGHTLY EARLIER FROPA TIMING FROM
YESTERDAY/S RUNS WILL LIKELY YIELD LITTLE THREAT FOR SEVERE WX AS
THE FRONT SHOULD BE EAST OF MUCH OF THE FORECAST AREA BY THU
AFTERNOON/S PEAK HEATING CYCLE. REGARDLESS...HAVE MAINTAINED
LIKELY POPS BOTH WED NGT AND THU AS MODELS SHOW PLENTY OF QPF IN
THE WARM SECTOR PRIOR TO AND DURING FRONTAL PASSAGE. BY FRI...FCST
MODELS SHOW SFC HIGH PRESSURE BUILDING INTO THE REGION WHICH
SHOULD YIELD OF BRIEF REPRIEVE FROM SHWR ACTIVITY. BY THE
WEEKEND...BOTH GFS AND ECMWF SUGGEST UPPER-LEVEL ENERGY WILL
GRADUALLY SHEAR OFF FROM MAIN UPPER FLOW RESULTING IN THE
DEVELOPMENT OF A CLOSED UPPER LOW WHICH WILL GRADUALLY RETROGRADE
WEST FROM THE CENTRAL/NORTHERN APPALACHIANS INTO THE TENNESSEE
AND OHIO VLYS. AS THIS OCCURS...FCST GUIDANCE SHOWS A DEVELOPING
FETCH OF ATLANTIC MOISTURE WORKING NORTHWEST INTO THE
MID-ATLANTIC REGION WHICH SHOULD LEAD TO REDEVELOPING SHWRS BY
NEXT WEEKEND.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
MAIN CONCERN HEADING INTO TODAY WILL BE POSSIBLE SHWRS/STORM
DEVELOPMENT LATER THIS AFTERNOON AS UPPER STORM SYSTEM APPROACHES
FROM THE SOUTHWEST. FOR NOW...FEEL BULK OF THE MORNING HRS SHOULD
BE PRECIP FREE WITH ACTIVITY THEN DEVELOPING AFTER 18Z. FCST
GUIDANCE SUGGESTING WEAK INSTABILITY LATER THIS AFTERNOON AND THUS
HAVE ADVERTISED A 3 HR TEMPO GROUP FOR THUNDER AT ALL SITES.
MOVING INTO TONIGHT...DIURNAL STORMS SHOULD COME TO AN END BEFORE
00Z WITH BULK OF ACTIVITY THEN TRANSITIONING BACK TO PLAIN SHWRS.
BEYOND 06Z...GUIDANCE SUGGESTS WIDESPREAD RESTRICTIONS DEVELOPING
HOWEVER CONTINUED SOUTHWEST FLOW LENDS ONLY MARGINAL CONFIDENCE OF
THIS SCENARIO DEVELOPING. DESPITE THIS...HAVE NUDGED TOWARDS
LOW-END MVFR UNTIL BETTER CONFIDENCE ARRIVES WITH FUTURE MODEL
GUIDANCE.
.OUTLOOK...
MONDAY THROUGH THURSDAY...SCT SHRA/TSRA ARE ANTICIPATED EACH
AFTN/EVE...WITH BRIEF RESTRICTIONS PSBL. MVFR RESTRICTIONS ALSO
PSBL IN EARLY MRNG STRATUS/FOG. OTRW VFR PREVAILS.
THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...
SHORT TERM...PVN
LONG TERM...CMG
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
702 AM EDT SUN JUL 7 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST OVER THE REGION THROUGH
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY DURING
THE AFTERNOON. SINCE THE AIRMASS REMAINS VERY MOIST ANY
THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL. THE UPPER
LEVEL TROUGH WILL EXIT THE NORTHEASTERN UNITED STATES MONDAY NIGHT
BRINGING A BRIEF END TO THE RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...
JUST DID ANOTHER MAJOR RE-WORK OF THE POPS GRIDS AS S/WV IS
EXITING STAGE RIGHT AT THIS TIME, TAKING THE STORMS WITH IT IN THE
NEXT HR. BASED ON LATEST RUC FCST AND CURRENT TRENDS NOT EXPECTING
MUCH IN THE WAY OF SHOWERS TO GET IN HERE BFR 15Z AND ONLY SCTD,
AT BEST, AFTER THAT TIME.
520 AM UPDATE...
QUICK UPDATE TO UP POPS ACRS UPSTATE NY TO 50% FOR CLUSTER OF
TSTMS MVG THRU NRN ZONES. ALSO UPPED QPF TO AROUND 0.25 INCHES
BASIN-AVERAGE THRU 12Z THO LOCALLY HIGHER AMNTS MAY EXIST.
330 AM UPDATE...
BERMUDA RIDGE CONTS TO SPIN OFF THE ATLANTIC COAST WITH PLENTIFUL
MOISTURE BEING PUMPED INTO CWA FM GOM. UL TROF/LOW IS ON THE MV AS
RIDGE IS WEAKENING. S/WV LOCATED ACRS OH/KY AREA WL APPCH THE FA
THIS AFTN AND RESULT IN A GOOD CHC FOR SHRA/TSRA ACTIVITY. THUS WL
GO WITH LKLY POPS ACRS WRN ZONES ARND 18Z OR SO THEN DIMINISHING AFT
THAT AS WV PASSES OFF TO THE WEST AND MID-LVL LAPSE RATES WEAKEN.
AS FOR SVR POTENTIAL, EXPECT ONLY A STRONG STORM OR TWO AS 0-6KM
BULK SHEAR VALUES WEAKEN THRU THE DAY. ANY TSTM THAT CAN DVLP WL HV
THE POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS AND LOCALIZED FLOODING
AND THIS WL LKLY BE THE MAIN THREAT FOR THIS AFTN.
H8 TEMPS TO ARND 17C TDA WL YIELD HIGHS IN THE M/U 80S SIMILAR TO
YDA.
FOR TONIGHT, UL LOW WL OPEN UP ACRS NRN OHIO BY 06Z AND BEGIN TO
EJECT EAST WITH SCTD THUNDER RMNG ACRS THE REGION THRU 12Z MONDAY.
EXPECTING OVRNGT MINS TO RMN UP IN THE U60S WITH DWPTS RMNG JUST A
DEGREE OR TWO LOWER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
330 AM UPDATE...
UPR TROF WL BE EJECTING OUT DRG THE DAY ON MONDAY WITH PW VALUES
GRADUALLY DROPPING THRU THE AFTN. POTENTIAL EXISTS FOR LCLY HVYR
RAINFALL THRU THE COURSE OF THE DAY WITH UL TROF INTERACTING WITH
FRONTAL BNDRY ACRS THE NERN U.S. THIS, IN ADDITION TO SATURATED SOIL
CONDS WL BRING A HEIGHTENED THREAT FOR FLOODING ON MONDAY. THUS, WL
HIGHLIGHT THREAT IN THE HWO.
PCPN SHUD GRADUALLY WIND DOWN MON NGT AS FLOW TRANSITIONS TO A MORE
ZONAL FLOW ALOFT. DIURNAL CONVECTION WL ONCE AGAIN BE POSSIBLE TUE
AFTN BFR TAPERING OFF TUE NGT, AHD OF NEXT H5 TROF HEADED IN FM THE
WEST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FAIRLY ACTIVE WX PATTERN EXPECTED TO PERSIST RIGHT THROUGH THE
CONCLUSION OF THE LONG TERM PERIOD AS A STRONG COLD FRONT PASSES
THROUGH THE AREA ON EARLY THURSDAY...FOLLOWED BY A AN UPPER
CLOSED LOW STALLING OVER THE TENNESSEE VALLEY BY WEEK/S END.
MODELS REMAIN IN EXCELLENT AGREEMENT ON THE TIMING OF THE
AFOREMENTIONED COLD FRONT WITH THE GFS...ECMWF AND CANADIAN-CMC
SOLUTIONS ALL FAVORING AN LATE WED/EARLY THU MORNING PASSAGE. FROM
THIS VANTAGE POINT...THE SLIGHTLY EARLIER FROPA TIMING FROM
YESTERDAY/S RUNS WILL LIKELY YIELD LITTLE THREAT FOR SEVERE WX AS
THE FRONT SHOULD BE EAST OF MUCH OF THE FORECAST AREA BY THU
AFTERNOON/S PEAK HEATING CYCLE. REGARDLESS...HAVE MAINTAINED
LIKELY POPS BOTH WED NGT AND THU AS MODELS SHOW PLENTY OF QPF IN
THE WARM SECTOR PRIOR TO AND DURING FRONTAL PASSAGE. BY FRI...FCST
MODELS SHOW SFC HIGH PRESSURE BUILDING INTO THE REGION WHICH
SHOULD YIELD OF BRIEF REPRIEVE FROM SHWR ACTIVITY. BY THE
WEEKEND...BOTH GFS AND ECMWF SUGGEST UPPER-LEVEL ENERGY WILL
GRADUALLY SHEAR OFF FROM MAIN UPPER FLOW RESULTING IN THE
DEVELOPMENT OF A CLOSED UPPER LOW WHICH WILL GRADUALLY RETROGRADE
WEST FROM THE CENTRAL/NORTHERN APPALACHIANS INTO THE TENNESSEE
AND OHIO VLYS. AS THIS OCCURS...FCST GUIDANCE SHOWS A DEVELOPING
FETCH OF ATLANTIC MOISTURE WORKING NORTHWEST INTO THE
MID-ATLANTIC REGION WHICH SHOULD LEAD TO REDEVELOPING SHWRS BY
NEXT WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MAIN CONCERN HEADING INTO TODAY WILL BE POSSIBLE SHWRS/STORM
DEVELOPMENT LATER THIS AFTERNOON AS UPPER STORM SYSTEM APPROACHES
FROM THE SOUTHWEST. FOR NOW...FEEL BULK OF THE MORNING HRS SHOULD
BE PRECIP FREE WITH ACTIVITY THEN DEVELOPING AFTER 18Z. FCST
GUIDANCE SUGGESTING WEAK INSTABILITY LATER THIS AFTERNOON AND THUS
HAVE ADVERTISED A 3 HR TEMPO GROUP FOR THUNDER AT ALL SITES.
MOVING INTO TONIGHT...DIURNAL STORMS SHOULD COME TO AN END BEFORE
00Z WITH BULK OF ACTIVITY THEN TRANSITIONING BACK TO PLAIN SHWRS.
BEYOND 06Z...GUIDANCE SUGGESTS WIDESPREAD RESTRICTIONS DEVELOPING
HOWEVER CONTINUED SOUTHWEST FLOW LENDS ONLY MARGINAL CONFIDENCE OF
THIS SCENARIO DEVELOPING. DESPITE THIS...HAVE NUDGED TOWARDS
LOW-END MVFR UNTIL BETTER CONFIDENCE ARRIVES WITH FUTURE MODEL
GUIDANCE.
.OUTLOOK...
MONDAY THROUGH THURSDAY...SCT SHRA/TSRA ARE ANTICIPATED EACH
AFTN/EVE...WITH BRIEF RESTRICTIONS PSBL. MVFR RESTRICTIONS ALSO
PSBL IN EARLY MRNG STRATUS/FOG. OTRW VFR PREVAILS.
THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...CMG
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
629 AM EDT SUN JUL 7 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST OVER THE REGION THROUGH
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY DURING
THE AFTERNOON. SINCE THE AIRMASS REMAINS VERY MOIST ANY
THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL. THE UPPER
LEVEL TROUGH WILL EXIT THE NORTHEASTERN UNITED STATES MONDAY NIGHT
BRINGING A BRIEF END TO THE RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...
JUST DID ANOTHER MAJOR RE-WORK OF THE POPS GRIDS AS S/WV IS
EXITING STAGE RIGHT AT THIS TIME, TAKING THE STORMS WITH IT IN THE
NEXT HR. BASED ON LATEST RUC FCST AND CURRENT TRENDS NOT EXPECTING
MUCH IN THE WAY OF SHOWERS TO GET IN HERE BFR 15Z AND ONLY SCTD,
AT BEST, AFTER THAT TIME.
520 AM UPDATE...
QUICK UPDATE TO UP POPS ACRS UPSTATE NY TO 50% FOR CLUSTER OF
TSTMS MVG THRU NRN ZONES. ALSO UPPED QPF TO AROUND 0.25 INCHES
BASIN-AVERAGE THRU 12Z THO LOCALLY HIGHER AMNTS MAY EXIST.
330 AM UPDATE...
BERMUDA RIDGE CONTS TO SPIN OFF THE ATLANTIC COAST WITH PLENTIFUL
MOISTURE BEING PUMPED INTO CWA FM GOM. UL TROF/LOW IS ON THE MV AS
RIDGE IS WEAKENING. S/WV LOCATED ACRS OH/KY AREA WL APPCH THE FA
THIS AFTN AND RESULT IN A GOOD CHC FOR SHRA/TSRA ACTIVITY. THUS WL
GO WITH LKLY POPS ACRS WRN ZONES ARND 18Z OR SO THEN DIMINISHING AFT
THAT AS WV PASSES OFF TO THE WEST AND MID-LVL LAPSE RATES WEAKEN.
AS FOR SVR POTENTIAL, EXPECT ONLY A STRONG STORM OR TWO AS 0-6KM
BULK SHEAR VALUES WEAKEN THRU THE DAY. ANY TSTM THAT CAN DVLP WL HV
THE POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS AND LOCALIZED FLOODING
AND THIS WL LKLY BE THE MAIN THREAT FOR THIS AFTN.
H8 TEMPS TO ARND 17C TDA WL YIELD HIGHS IN THE M/U 80S SIMILAR TO
YDA.
FOR TONIGHT, UL LOW WL OPEN UP ACRS NRN OHIO BY 06Z AND BEGIN TO
EJECT EAST WITH SCTD THUNDER RMNG ACRS THE REGION THRU 12Z MONDAY.
EXPECTING OVRNGT MINS TO RMN UP IN THE U60S WITH DWPTS RMNG JUST A
DEGREE OR TWO LOWER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
330 AM UPDATE...
UPR TROF WL BE EJECTING OUT DRG THE DAY ON MONDAY WITH PW VALUES
GRADUALLY DROPPING THRU THE AFTN. POTENTIAL EXISTS FOR LCLY HVYR
RAINFALL THRU THE COURSE OF THE DAY WITH UL TROF INTERACTING WITH
FRONTAL BNDRY ACRS THE NERN U.S. THIS, IN ADDITION TO SATURATED SOIL
CONDS WL BRING A HEIGHTENED THREAT FOR FLOODING ON MONDAY. THUS, WL
HIGHLIGHT THREAT IN THE HWO.
PCPN SHUD GRADUALLY WIND DOWN MON NGT AS FLOW TRANSITIONS TO A MORE
ZONAL FLOW ALOFT. DIURNAL CONVECTION WL ONCE AGAIN BE POSSIBLE TUE
AFTN BFR TAPERING OFF TUE NGT, AHD OF NEXT H5 TROF HEADED IN FM THE
WEST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A FAIRLY ACTIVE WX PATTERN EXPECTED TO PERSIST RIGHT THROUGH THE
CONCLUSION OF THE LONG TERM PERIOD AS A STRONG COLD FRONT PASSES
THROUGH THE AREA ON EARLY THURSDAY...FOLLOWED BY A AN UPPER
CLOSED LOW STALLING OVER THE TENNESSEE VALLEY BY WEEK/S END.
MODELS REMAIN IN EXCELLENT AGREEMENT ON THE TIMING OF THE
AFOREMENTIONED COLD FRONT WITH THE GFS...ECMWF AND CANADIAN-CMC
SOLUTIONS ALL FAVORING AN LATE WED/EARLY THU MORNING PASSAGE. FROM
THIS VANTAGE POINT...THE SLIGHTLY EARLIER FROPA TIMING FROM
YESTERDAY/S RUNS WILL LIKELY YIELD LITTLE THREAT FOR SEVERE WX AS
THE FRONT SHOULD BE EAST OF MUCH OF THE FORECAST AREA BY THU
AFTERNOON/S PEAK HEATING CYCLE. REGARDLESS...HAVE MAINTAINED
LIKELY POPS BOTH WED NGT AND THU AS MODELS SHOW PLENTY OF QPF IN
THE WARM SECTOR PRIOR TO AND DURING FRONTAL PASSAGE. BY FRI...FCST
MODELS SHOW SFC HIGH PRESSURE BUILDING INTO THE REGION WHICH
SHOULD YIELD OF BRIEF REPRIEVE FROM SHWR ACTIVITY. BY THE
WEEKEND...BOTH GFS AND ECMWF SUGGEST UPPER-LEVEL ENERGY WILL
GRADUALLY SHEAR OFF FROM MAIN UPPER FLOW RESULTING IN THE
DEVELOPMENT OF A CLOSED UPPER LOW WHICH WILL GRADUALLY RETROGRADE
WEST FROM THE CENTRAL/NORTHERN APPALACHIANS INTO THE TENNESSEE
AND OHIO VLYS. AS THIS OCCURS...FCST GUIDANCE SHOWS A DEVELOPING
FETCH OF ATLANTIC MOISTURE WORKING NORTHWEST INTO THE
MID-ATLANTIC REGION WHICH SHOULD LEAD TO REDEVELOPING SHWRS BY
NEXT WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AREA RADARS THIS MORNING SHOWING DEVELOPING CONVECTION THIS HR
ACROSS WESTERN NY IN ADVANCE OF A SHORTWAVE DISTURBANCE LIFTING
NORTH THROUGH EASTERN OHIO. SO FAR THIS ACTIVITY HAS SHOWN A
WEAKENING TREND AS IT PROGRESSES EAST AND THUS HAVE NOT
HIGHLIGHTED THUNDER IN ANY TERMINALS OUT OF THE GATE THIS MORNING.
OBVIOUSLY TRENDS WILL HAVE TO BE WATCHED WITH AND UPDATES MADE ON
AN AS NEEDED BASIS.
UPSTREAM SATELLITE TRENDS ALSO SHOWING SOME PARTIAL CLEARING
WORKING NORTH FROM EASTERN PA THIS HR. AS A RESULT...MAIN CONCERN
FOR THE NEXT 6-HRS IN ADDITION TO THE CONVECTION WILL BE THE
POSSIBILITY FOR IFR VSBYS IN FOG AS WE PROGRESS THROUGH THE
MORNING. FOR NOW HAVE ADVERTISED BELOW ALTERNATE MIN CONDITIONS
DEVELOPING AT THE TERMINAL WITH DIURNAL IMPROVEMENTS LIKELY AFTER
11Z IF FOG DOES DEVELOP. ELSEWHERE...MVFR VSBYS POSSIBLE AT ITH
AND AVP AFTER THE 09Z TIME FRAME.
SHWRS EXPECTED TO BECOME MORE PREVALENT AS THE DAY CONTINUES AS A
STRONG UPPER-LEVEL DISTURBANCES GRADUALLY APPROACHES THE AREA.
STORMS WILL ALSO BE POSSIBLE BUT HAVE ELECTED TO HOLD OFF
MENTIONING FOR NOW BASED ON DISTANCE INTO THE FCST AND MARGINAL
CONFIDENCE.
WINDS WILL REMAIN FROM THE WEST BETWEEN 5-10 KTS THROUGH THE
PERIOD BEFORE WEAKENING THIS EVENING.
.OUTLOOK...
MONDAY THROUGH THURSDAY...SCT SHRA/TSRA ARE ANTICIPATED EACH
AFTN/EVE...WITH BRIEF RESTRICTIONS PSBL. MVFR RESTRICTIONS ALSO
PSBL IN EARLY MRNG STRATUS/FOG. OTRW VFR PREVAILS.
THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...CMG
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1027 AM EDT SUN JUL 7 2013
.SYNOPSIS...
A WEAKENING UPPER LEVEL LOW WILL TRACK INTO THE OHIO VALLEY THIS
AFTERNOON...PROGRESSING EAST ACROSS THE MID-ATLANTIC TONIGHT.
CYCLONIC FLOW ALOFT WILL PREVAIL OVER THE EASTERN UNITED STATES
THROUGH MID WEEK...WITH AN UNSEASONABLY DEEP UPPER LEVEL TROUGH
DIGGING SOUTHEAST IN THE MID-ATLANTIC BY FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1025 AM SUNDAY...
SOME VERY LIGHT SHOWERS HAVE DEVELOPED OVER THE SOUTHERN PIEDMONT
AND SANDHILLS THIS MORNING. AS WITH YESTERDAY...THE HRRR HIGH RES
CAM IS DOING A GOOD JOB SIMULATING THE CURRENT SHOWER ACTIVITY. THE
LATEST RUN OF THE HRRR SHOWS AN INCREASE IN SHOWER COVERAGE...MAINLY
IN THE NORTHEAST PIEDMONT AND SANDHILLS THROUGH THIS AFTERNOON...
WITH THE MORE WIDESPREAD CONVECTION MOVING INTO THE NORTHWEST
PIEDMONT LATE THIS AFT/EVE. 12Z UPPER AIR ANALYSES SHOW THE LOW WEST
OF THE APPALACHIANS OVER IL/IN...WITH HIGH PRESSURE OFF THE CAROLINA
COAST. WHILE CENTRAL NC IS RELATIVELY DRY...LOW LEVEL MOISTURE IS
ADVECTING IN OFF THE GULF AHEAD OF THE LOW PRESSURE SYSTEM. AS THE
UPPER LEVEL LOW MOVES EASTWARD TODAY SO WILL THE LOW/MID LEVEL
MOISTURE AND SHOWERS/STORMS...CURRENTLY OVER THE MOUNTAINS. -KC
PRECIPITATION CHANCES:
SW FLOW ALOFT WILL STRENGTHEN FROM THE WEST TODAY...WITH AN
INCREASING POTENTIAL FOR SMALL AMPLITUDE SHORTWAVES TRACKING
NORTHEAST ACROSS WESTERN NC/VA THIS AFT/EVE...FOLLOWED BY ADDITIONAL
DPVA WITHIN INCREASINGLY CYCLONIC FLOW ALOFT AS THE UPPER LEVEL LOW
TRACKS INTO WESTERN PA BETWEEN 00-06Z TONIGHT. SHALLOW CONVERGENCE
IN VICINITY OF A DEVELOPING PIEDMONT SFC TROUGH ASSOCIATED WITH
SUBTLE HEIGHT FALLS IN ADVANCE OF THE UPPER LEVEL WAVE APPROACHING
THE REGION THIS AFT/EVE WILL SERVE AS A POTENTIAL FOCUS FOR DIURNAL
CONVECTION THIS AFTERNOON...FOLLOWED BY SOMEWHAT DEEPER CONVERGENCE
TONIGHT AS THE LOW-LEVEL TROUGH SHARPENS IN RESPONSE TO STRONGER
HEIGHT FALLS /CYCLONIC FLOW ALOFT/ OVER THE MID-ATLANTIC. SEASONAL
BOUNDARY LAYER MOISTURE/DESTABILIZATION CAN BE EXPECTED AGAIN THIS
AFTERNOON...WITH MLCAPE VALUES GENERALLY IN THE 1000-2000 J/KG RANGE
ACROSS CENTRAL NC...THOUGH A WEST-EAST MID-LEVEL MOISTURE GRADIENT
WILL PERSIST WITH DEEPER MOISTURE ACROSS THE FOOTHILLS/WESTERN
PIEDMONT AND A DRIER AIRMASS ALOFT IN THE COASTAL PLAIN. WITH THE
ABOVE IN MIND...EXPECT THE BEST CHANCE FOR CONVECTION THIS AFTERNOON
AND EARLY EVENING WEST OF THE HWY 1 CORRIDOR IN VICINITY OF THE
PIEDMONT SFC TROUGH AND IN CLOSER PROXIMITY TO SMALL AMPLITUDE
SHORTWAVES/DEEPER MOISTURE IN STRENGTHENING SW FLOW ALOFT. WILL
INDICATE PRECIP CHANCES RANGING FROM 20% EAST OF I-95 TO 50-60% IN
THE FAR W/NW PIEDMONT. CONVECTION SHOULD PERSIST INTO TONIGHT ACROSS
THE NORTHERN AND WESTERN PIEDMONT AS BETTER DPVA /STRONGER CYCLONIC
FLOW ALOFT/ PROGRESSES INTO THE MID-ATLANTIC.
TEMPERATURES:
EXPECT HIGHS TODAY SIMILAR TO PREVIOUS DAYS WITH VERY SIMILAR
REASONING...THOUGH PERHAPS SLIGHTLY WARMER GIVEN A MORE
SOUTHWESTERLY LOW-LEVEL FLOW...ESP. ALONG AND EAST OF THE HWY 1
CORRIDOR...WITH HIGHS RANGING FROM THE MID 80S FAR NW PIEDMONT TO
UPPER 80S AND LOWER 90S ELSEWHERE. LOWS TONIGHT SIMILAR TO PREVIOUS
NIGHTS IN THE LOWER 70S.
SEVERE THREAT:
GIVEN DEEP LAYER SHEAR IN THE 25-35 KT RANGE ACROSS THE N/NW
PIEDMONT IN THE PRESENCE OF MODERATE INSTABILITY (1000-2000 J/KG
MLCAPE) AND DCAPE VALUES PROGGED AS HIGH AS 1000-1500 J/KG THIS AFT
AND EARLY EVE...ANTICIPATE A POTENTIAL FOR DAMAGING WINDS...
PRIMARILY WEST AND NW OF THE TRIANGLE. -VINCENT
&&
.SHORT TERM /MONDAY/...
AS OF 325 AM SUNDAY...
ALTHOUGH THE AFOREMENTIONED UPPER LEVEL WAVE WILL TRACK EAST THROUGH
THE MID-ATLANTIC EARLY MONDAY MORNING...CYCLONIC FLOW ALOFT AND
LOW-LEVEL TROUGHING WILL PERSIST ACROSS THE AREA MONDAY
AFT/EVE...WITH ADDITIONAL SHORTWAVE ENERGY ANTICIPATED TO DIG
SOUTHEAST INTO NC/VA IN VICINITY OF PEAK HEATING. AS A RESULT...
EXPECT ABOVE NORMAL CHANCES FOR CONVECTION...PRIMARILY DURING THE
AFTERNOON AND EVENING HOURS...WITH HIGHS SIMILAR TO PREVIOUS DAYS...
IN THE MID/UPPER 80S TO NEAR 90F. -VINCENT
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
NWP GUIDANCE IS IN GOOD AGREEMENT OF ANOTHER PERIOD OF UNSETTLED
WEATHER WITH ABOVE NORMAL CHANCES OF PRECIPITATION FOR THE UPCOMING
WEEK. THE EXTENDED RANGE WILL FEATURE A PERSISTENT AND STRONG RIDGE
ACROSS THE SOUTHERN ROCKY MOUNTAINS AND A WEAKER BUT RELATIVELY
STATIONARY AREA OF RIDGING OFF THE SOUTHEAST U.S. COAST. A SLOWLY
WESTWARD ADVANCING CLOSED UPPER LOW MOVES WEST UNDER THE SUBTROPICAL
ATLANTIC RIDGE REACHING FLORIDA ON TUESDAY AND THEN MOVES INTO THE
EASTERN GULF OF MEXICO ON WEDNESDAY AND THURSDAY. A DIGGING SHORT
WAVE TROUGH AND ASSOCIATED COLD FRONT DROPS INTO THE GREAT LAKES
REGION ON WEDNESDAY REACHING THE MID ATLANTIC LATE THURSDAY AND THEN
CLOSES OFF ON FRIDAY. THIS UPPER LOW DRIFTS SOUTHWEST INTO THE
EASTERN TENNESSEE VALLEY BY SATURDAY. THE AIR MASS THROUGH THE
PERIOD WILL REMAIN MOIST AND UNSTABLE WITH AN AXIS OF HIGH
PRECIPITABLE WATER LINGERING ACROSS THE CAROLINAS AND VIRGINIA
THROUGH MOST/ALL OF THE PERIOD.
SENSIBLE WEATHER CONDITIONS WILL FEATURE AN UNSETTLED SUMMERTIME
PATTERN WITH A HUMID AIR MASS AND THE THREAT OF MAINLY AFTERNOON AND
EVENING CONVECTION EACH DAY. THE THREAT OF CONVECTION WILL BE
GREATEST ON THURSDAY AND THURSDAY NIGHT WHEN NWP GUIDANCE IS IN GOOD
AGREEMENT THAT A SHORTWAVE TROUGH AND COLD FRONT WILL APPROACH THE
REGION. UNSETTLED WEATHER WITH ABOVE CLIMATOLOGY POPS WILL LIKELY
PERSIST ON FRIDAY THROUGH SATURDAY ALTHOUGH THERE IS STILL SOME
UNCERTAINTY ON WHERE THE SURFACE BOUNDARY AND MAIN MOISTURE FEED
WILL SETUP. NEAR SEASONABLE TEMPERATURES ARE EXPECTED WITH HIGHS
AROUND 90 WITH MORNING LOWS IN THE LOWER TO MID 70S. -BLAES
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 700 AM SUNDAY...
24-HR TAF PERIOD:
SUB-VFR STRATUS AT THE INT/GSO TERMINALS WILL GRADUALLY LIFT AND
SCATTER OUT TO VFR BY 13-15Z. EXPECT ISOLD/SCT CONVECTION THIS
AFTERNOON THROUGH THIS EVENING (16-04Z)...WITH THE BEST CHANCE AT
THE INT/GSO TERMINALS. A CHANCE OF SHOWERS WILL PERSIST OVERNIGHT/
MONDAY MORNING AS AN UPPER LEVEL DISTURBANCE TRACKS EAST THROUGH THE
OH VALLEY INTO THE MID-ATLANTIC...ALONG WITH A POTENTIAL FOR
MVFR/IFR CEILINGS BY 08-12Z MON.
LOOKING AHEAD:
AVIATION CONDITIONS THROUGH MID/LATE WEEK WILL BE CHARACTERIZED BY
AN ABOVE NORMAL CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY
(PRIMARILY AFTERNOON AND EVENING HOURS) IN ASSOCIATION WITH CYCLONIC
FLOW ALOFT AND AN ABOVE NORMAL CHANCE FOR MVFR/IFR STRATUS OR FOG
EACH MORNING (PRIMARILY 07-13Z) IN ASSOCIATION WITH A PERSISTENT
MOIST SOUTHERLY RETURN FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...KC/VINCENT
SHORT TERM...VINCENT
LONG TERM...BLAES
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1043 AM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 958 AM CDT SUN JUL 7 2013
UPDATE TO SCALE BACK POPS WEST AND CENTRAL THIS AFTERNOON AND
EVENING...AS COVERAGE OF STORMS NOW EXPECTED TO BE LESS BASED ON
RECENT HI-RES MODEL RUNS. ISOLATED SEVERE STORMS WILL BE
POSSIBLE...MAINLY IN THE EARLY EVENING ACROSS THE FAR SOUTHWEST. ANOTHER
SHORT WAVE MAY GLANCE NORTHERN COUNTIES OVERNIGHT WITH ADDITIONAL
STORMS...BUT CONFIDENCE IN THIS SCENARIO IS LOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUL 7 2013
EARLY MORNING SURFACE ANALYSIS PLACED A WEAK SURFACE TROUGH ACROSS
EASTERN NORTH DAKOTA. THE TROUGH WAS THE FOCUS FOR ISOLATED
THUNDERSTORMS EARLIER THIS MORNING...BUT THEY HAVE SINCE
DIMINISHED. THE TROUGH WILL MOVE SLOWLY EAST THIS MORNING...TAKING
THE THREAT OF ADDITIONAL THUNDERSTORMS WITH IT.
THE NEXT CONCERN WILL BE SHOWERS / THUNDERSTORMS IN EASTERN
MONTANA WHICH HAVE BEEN MAKING STEADY PROGRESS TOWARDS WESTERN
NORTH DAKOTA EARLY THIS MORNING. THE STORMS IN EASTERN MONTANA ARE
IN PART BEING DRIVEN BY A SHORT WAVE WHICH IS EXPECTED TO MOVE
INTO WESTERN NORTH DAKOTA THIS MORNING...AND INTO CENTRAL NORTH
DAKOTA THIS AFTERNOON. VARIOUS MODEL SOLUTIONS (NAM / RAP / GFS /
4KM WRF) ALL SUGGEST THERE WILL BE A CHANCE OF PRECIPITATION AS
THE WAVE MOVES ACROSS THE FORECAST AREA. WHERE THEY DIFFER TO SOME
EXTENT IS IN THEIR COVERAGE OF PRECIPITATION. WILL HOLD ONTO
CHANCE POPS ACROSS MOST OF THE FORECAST AREA TODAY / THIS EVENING
WITH THE HIGHER POPS IN THE WEST. THE LATEST DAY 1 OUTLOOK PLACES
THE SOUTHWEST PART OF THE STATE IN A SLIGHT RISK...WHICH APPEARS
REASONABLE SINCE THAT AREA IS FORECAST TO HAVE THE GREATEST
INSTABILITY THIS AFTERNOON / EVENING WITH MLCAPE VALUES OF UP TO
1500 J/KG.
CONFIDENCE IN THUNDERSTORM COVERAGE LATE TONIGHT INTO EARLY MONDAY
MORNING DECREASES TO SOME EXTENT AS THE INITIAL WAVE MOVES EAST.
CONFLICTING SIGNALS ARE SHOWN IN THE MODEL SOLUTIONS WITH SOME
SUGGESTING LIMITED THUNDERSTORM COVERAGE OVERNIGHT...WHILE OTHERS
BRING ADDITIONAL THUNDERSTORMS INTO WESTERN NORTH DAKOTA FROM
EASTERN MONTANA. WILL HOLD ONTO CHANCE POPS IN THE CENTRAL AND
WEST...WITH SLIGHT CHANCES IN THE EAST WHERE CONFIDENCE IN
ADDITIONAL CONVECTION IS LOWER.
CLOUDS FROM SHOWERS / THUNDERSTORMS COULD INFLUENCE TEMPERATURES
TODAY. WILL FOLLOW A BLEND OF GUIDANCE VALUES WITH HIGHS NEAR 80
NORTH...AND LOWER TO MID 80S SOUTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUL 7 2013
MODELS AGREE IN A SOUTHWEST FLOW ALOFT FROM THE NORTHWEST US TO
THE NORTHERN PLAINS EARLY IN THE PERIOD. AN ACTIVE SHORTWAVE
PATTERN WILL BRING SEVERAL SHORTWAVES THROUGH THE REGION BRINGING
SOME WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE REGION MONDAY
NIGHT AND TUESDAY. THIS WILL BE FOLLOWED BY A BREAK IN THE
PRECIPITATION CHANCES WEDNESDAY AND THURSDAY AS AN H500 RIDGE
POSITIONS ITSELF OVER THE NORTHERN PLAINS. AS THIS FEATURE MOVES
EAST BY NEXT WEEKEND WILL SEE AT LEAST A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS RETURN FOR FRIDAY AND SATURDAY.
THE PRIMARY FOCUS WILL BE MONDAY NIGHT. BY MONDAY AFTERNOON LOW
PRESSURE WILL DEVELOP ACROSS MONTANA BRINGING A EASTERLY WIND FLOW
ACROSS WEST AND CENTRAL NORTH DAKOTA. THIS WILL PULL ABUNDANT
MOISTURE INTO THE REGION. MODEL SOUNDINGS FORECAST PWATS BETWEEN
1.5 AND 1.75 INCHES...OR ROUGHLY 2 STANDARD DEVIATIONS ABOVE
NORMAL IF CORRECT. WITH ABUNDANT MOISTURE WILL MENTION HEAVY RAIN
IN THE HWO ALONG WITH SLIGHT CHANCE SEVERE FROM SPC MONDAY NIGHT.
THUNDERSTORMS WILL END TUESDAY FOLLOWED BY THE DRY WEATHER
WEDNESDAYS AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 958 AM CDT SUN JUL 7 2013
WESTERN NORTH DAKOTA WILL BE THE PRIMARY FOCUS FOR SCATTERED
THUNDERSTORMS TODAY AND TONIGHT...MAINLY IMPACTING KDIK/KISN. STORMS
ARE EXPECTED TO BE TOO SCATTERED IN NATURE TO WARRANT MORE THAN A
VCTS GROUP AT THIS TIME. OTHER THAN BRIEF MVFR VSBYS IN THE MORE
INTENSE STORMS...EXPECT VFR CONDITIONS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...CK
LONG TERM...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1014 AM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 1009 AM CDT SUN JUL 7 2013
LOW CLOUDS AND FOG IN THE FAR EASTERN FCST AREA DISSIPATING AS
EXPECTED. SOME PATCHY LOWER CLOUDS ROSEAU TO FOSSTON BUT AND THIS
BAND IS RIGHT ALONG THE WEAK SFC BOUNDARY. STILL TAKE SOME TIME TO
FULLY BREAKUP LOW CLOUDS IN THE EAST BUT SHOULD DO SO BY 17Z-18Z
AT THE LASTEST AS WINDS START TO INCREASE ENOUGH. OTHERWISE GOT
SOME HIGH CLOUDS SPREADING INTO DVL BASIN AND LIKELY WILL SPREAD
INTO SOUTHWESTERN FCST AREA AHD OF AREA OF SHOWERS/STORMS MOVING
THRU FAR SOUTH CENTRAL ND AND NORTHWESTERN SD. HRRR SEEMS
REASONABLE IN SHOWING ANY SHOWERS DYING OUT BEFORE REACHING
SOUTHWESTERN FCST AREA WITH ACTIVITY SHIFTING MORE INTO SOUTH
DAKOTA. THUS DRY FCST THRU 00Z IS GOOD. TOOK HIGH TEMPS DOWN A
LITTLE BIT...DUE TO SLOW START.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 258 AM CDT SUN JUL 7 2013
THE MAIN UPPER SHORTWAVE HAS BEEN LIFTING OFF INTO CANADA...WITH A
SFC BOUNDARY TRAILING SOUTH INTO EASTERN ND. WINDS HAVE ALREADY
SHIFTED TO THE WEST IN THE DEVILS LAKE BASIN AND DRIER AIR HAS
STARTED TO MOVE IN. MOIST AIR AND LIGHT WINDS CONTINUE FROM THE
RED RIVER VALLEY EASTWARD. THERE HAS BEEN SOME FOG FORMATION IN
SOME SPOTS...BUT WITH THE BOUNDARY COMING THROUGH THINK THAT IT
WILL BE SHORT LIVED. STORMS ALONG THE FRONT AS IT WENT THROUGH THE
DEVILS LAKE BASIN HAVE DISSIPATED...BUT WILL HOLD ONTO 20 POPS FOR
A BIT LONGER AS THE BOUNDARY MOVES THROUGH AND TAKE ANOTHER LOOK
BEFORE SENDING GRIDS OUT.
WEAK SFC HIGH PRESSURE WILL BUILD IN TODAY AND CONDITIONS WILL BE
FAIRLY QUIET. WITH PLENTY OF SUN HIGHS AGAIN SHOULD RANGE FROM THE
UPPER 70S TO MID 80S. NEAR ZONAL FLOW CONTINUES INTO
TONIGHT...WITH A WEAK SHORTWAVE BRINGING SOME CONVECTION TO
WESTERN ND. THINK THERE IS THE POSSIBILITY OF SOME ACTIVITY
DRIFTING INTO OUR FAR WESTERN COUNTIES LATE TONIGHT SO KEPT LOW
POPS GOING FOR NOW IN THAT AREA.
THE WEAK SHORTWAVE TROUGH WILL CONTINUE TO MOVE EASTWARD INTO
MONDAY...BUT THE MORE SIGNIFICANT SFC FEATURES WILL STAY TO THE
WEST AS A TROUGH DEVELOPS IN THE LEE OF THE ROCKIES. WINDS WILL
SHIFT BACK TO THE SOUTH AND HIGHS WILL AGAIN BE MAINLY IN THE 80S.
CONTINUED TO KEEP LOW POPS GOING IN THE WEST FOR ANY ACTIVITY
DRIFTING IN FROM CENTRAL ND.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 258 AM CDT SUN JUL 7 2013
MONDAY NIGHT INTO TUESDAY...A MORE SIGNIFICANT SHORTWAVE TROUGH
WILL BEGIN TO DIG DOWN INTO THE NORTHWESTERN PLAINS OUT OF CANADA
AND THEN MOVE THROUGH THE DAKOTAS. THERE SHOULD BE A DECENT SFC
TROUGH AND A COLD FRONT MOVING THROUGH DURING THE DAY ON TUESDAY.
MODELS ARE IN FAIRLY DECENT AGREEMENT ON BRINGING PRECIP THROUGH
MONDAY NIGHT INTO TUESDAY AS THE UPPER TROUGH AND SFC BOUNDARY
COME THROUGH ALTHOUGH THERE ARE DIFFERENCES IN TIMING AND
PLACEMENT. KEPT HIGH CHANCE TO LIKELY POPS GOING FOR NOW WITH ONLY
A FEW TWEAKS. PRECIP WILL TAPER OFF TUESDAY NIGHT AS HIGH PRESSURE
BUILDS IN. THE FRONT SHOULD KNOCK BACK TEMPS A FEW DEGREES
TUESDAY INTO TUESDAY NIGHT.
WEDNESDAY-SATURDAY...THE DEPARTING SHORTWAVE TROUGH WILL DIVE INTO
THE NORTHERN GREAT LAKES ON WEDNESDAY AS UPPER RIDGING BEGINS TO
AMPLIFY ACROSS THE ROCKIES. SURFACE HIGH PRESSURE BENEATH NORTHWEST
FLOW ALOFT WILL RESULT IN DRY WEATHER WEDNESDAY AND THURSDAY...WITH
SEASONABLE TEMPS AND LOWER HUMIDITY. TEMPS MAY CLIMB A FEW DEGREES
FROM WEDNESDAY TO THURSDAY AS WARM ADVECTION/RETURN FLOW KICKS IN.
FOR FRIDAY AND SATURDAY...OPERATIONAL MODELS KEEP THE AREA ON THE
EDGE OF THE UPPER RIDGE/HOT DOME CENTERED ACROSS THE ROCKIES/HIGH
PLAINS...IN THE VICINITY OF THE STRONGER WESTERLIES. UPPER LEVEL
IMPULSES SKIRTING ALONG THE PERIPHERY OF THE RIDGE WILL HELP TO
TRIGGER SCATTERED CONVECTION...BUT THE TIMING AND AMPLITUDE OF THESE
DISTURBANCE IS NOT CLEAR THIS FAR OUT...SO WILL CONTINUE LOW-END POPS
FRIDAY INTO SATURDAY. TEMPS TOWARDS NEXT WEEKEND CONTINUE TO LOOK
SEASONABLE OVERALL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 644 AM CDT SUN JUL 7 2013
PATCHY FOG HAS BROUGHT IFR OR LOWER CONDITIONS TO ALL BUT
KDVL...WITH KBJI SEEING 1/4 TO 1/2SM FOR THE PAST FEW HOURS. THINK
THAT THE REDUCED VIS WILL CONTINUE THROUGH THE NEXT HOUR OR SO IN
THE RED RIVER VALLEY...AND A BIT LONGER AT KBJI. THERE SHOULD BE
SOME GRADUAL IMPROVEMENT TO MVFR VIS AND THEN ALL SITES SHOULD BE
VFR AFTER 16Z. WINDS WILL SHIFT TO THE NORTHWEST BY LATE MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...JR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
642 AM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 621 AM CDT SUN JUL 7 2013
SHORTWAVE TROUGH MOVING THROUGH EASTERN MONTANA AT THIS TIME
GENERATING SEVERAL CLUSTERS OF THUNDERSTORMS. THE CONVECTION ALSO
SUPPORTED BY 75-90 KT ANTICYCLONICALLY CURVED H250 JET ACROSS
SOUTHEAST MANITOBA. FOCUSED ON THIS AREA FOR THE MORNING UPDATE. SO
RAISED THE CHANCE FOR THUNDERSTORMS SOUTHWEST. THIS EARLY
CONVECTION NOT EXPECTED TO BE SEVERE. WAITING FOR BETTER
INSTABILITY...STEEPER MID LEVEL LAPSE RATES AND BETTER CAPE THIS
AFTERNOON. BUT ISOLATED HAIL/GUSTY WIND POSSIBLE THIS MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUL 7 2013
EARLY MORNING SURFACE ANALYSIS PLACED A WEAK SURFACE TROUGH ACROSS
EASTERN NORTH DAKOTA. THE TROUGH WAS THE FOCUS FOR ISOLATED
THUNDERSTORMS EARLIER THIS MORNING...BUT THEY HAVE SINCE
DIMINISHED. THE TROUGH WILL MOVE SLOWLY EAST THIS MORNING...TAKING
THE THREAT OF ADDITIONAL THUNDERSTORMS WITH IT.
THE NEXT CONCERN WILL BE SHOWERS / THUNDERSTORMS IN EASTERN
MONTANA WHICH HAVE BEEN MAKING STEADY PROGRESS TOWARDS WESTERN
NORTH DAKOTA EARLY THIS MORNING. THE STORMS IN EASTERN MONTANA ARE
IN PART BEING DRIVEN BY A SHORT WAVE WHICH IS EXPECTED TO MOVE
INTO WESTERN NORTH DAKOTA THIS MORNING...AND INTO CENTRAL NORTH
DAKOTA THIS AFTERNOON. VARIOUS MODEL SOLUTIONS (NAM / RAP / GFS /
4KM WRF) ALL SUGGEST THERE WILL BE A CHANCE OF PRECIPITATION AS
THE WAVE MOVES ACROSS THE FORECAST AREA. WHERE THEY DIFFER TO SOME
EXTENT IS IN THEIR COVERAGE OF PRECIPITATION. WILL HOLD ONTO
CHANCE POPS ACROSS MOST OF THE FORECAST AREA TODAY / THIS EVENING
WITH THE HIGHER POPS IN THE WEST. THE LATEST DAY 1 OUTLOOK PLACES
THE SOUTHWEST PART OF THE STATE IN A SLIGHT RISK...WHICH APPEARS
REASONABLE SINCE THAT AREA IS FORECAST TO HAVE THE GREATEST
INSTABILITY THIS AFTERNOON / EVENING WITH MLCAPE VALUES OF UP TO
1500 J/KG.
CONFIDENCE IN THUNDERSTORM COVERAGE LATE TONIGHT INTO EARLY MONDAY
MORNING DECREASES TO SOME EXTENT AS THE INITIAL WAVE MOVES EAST.
CONFLICTING SIGNALS ARE SHOWN IN THE MODEL SOLUTIONS WITH SOME
SUGGESTING LIMITED THUNDERSTORM COVERAGE OVERNIGHT...WHILE OTHERS
BRING ADDITIONAL THUNDERSTORMS INTO WESTERN NORTH DAKOTA FROM
EASTERN MONTANA. WILL HOLD ONTO CHANCE POPS IN THE CENTRAL AND
WEST...WITH SLIGHT CHANCES IN THE EAST WHERE CONFIDENCE IN
ADDITIONAL CONVECTION IS LOWER.
CLOUDS FROM SHOWERS / THUNDERSTORMS COULD INFLUENCE TEMPERATURES
TODAY. WILL FOLLOW A BLEND OF GUIDANCE VALUES WITH HIGHS NEAR 80
NORTH...AND LOWER TO MID 80S SOUTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUL 7 2013
MODELS AGREE IN A SOUTHWEST FLOW ALOFT FROM THE NORTHWEST US TO
THE NORTHERN PLAINS EARLY IN THE PERIOD. AN ACTIVE SHORTWAVE
PATTERN WILL BRING SEVERAL SHORTWAVES THROUGH THE REGION BRINGING
SOME WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE REGION MONDAY
NIGHT AND TUESDAY. THIS WILL BE FOLLOWED BY A BREAK IN THE
PRECIPITATION CHANCES WEDNESDAY AND THURSDAY AS AN H500 RIDGE
POSITIONS ITSELF OVER THE NORTHERN PLAINS. AS THIS FEATURE MOVES
EAST BY NEXT WEEKEND WILL SEE AT LEAST A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS RETURN FOR FRIDAY AND SATURDAY.
THE PRIMARY FOCUS WILL BE MONDAY NIGHT. BY MONDAY AFTERNOON LOW
PRESSURE WILL DEVELOP ACROSS MONTANA BRINGING A EASTERLY WIND FLOW
ACROSS WEST AND CENTRAL NORTH DAKOTA. THIS WILL PULL ABUNDANT
MOISTURE INTO THE REGION. MODEL SOUNDINGS FORECAST PWATS BETWEEN
1.5 AND 1.75 INCHES...OR ROUGHLY 2 STANDARD DEVIATIONS ABOVE
NORMAL IF CORRECT. WITH ABUNDANT MOISTURE WILL MENTION HEAVY RAIN
IN THE HWO ALONG WITH SLIGHT CHANCE SEVERE FROM SPC MONDAY NIGHT.
THUNDERSTORMS WILL END TUESDAY FOLLOWED BY THE DRY WEATHER
WEDNESDAYS AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 621 AM CDT SUN JUL 7 2013
AT 6 AM CDT...A WEAK UPPER LEVEL DISTURBANCE WAS MOVING THROUGH
EASTERN MONTANA AND WESTERN NORTH DAKOTA. A MOIST UNSTABLE AIR
REMAINED ACROSS THE STATE. SCATTERED MORNING THUNDERSTORMS ARE
POSSIBLE WEST. THIS WILL HAVE IMPACTS TO KDIK. MENTIONS VCTS AT
FOR THE MORNING. OTHERWISE VFR AT ALL TAF SITES. ANOTHER ROUND OF
THUNDERSTORMS ARE POSSIBLE LATER THIS AFTERNOON AND THIS EVENING.
ALTHOUGH HIGHER IMPACTS EXPECTED TO THE SOUTHWEST...INCLUDING
KDIK...DID NOT MENTION FOR KDIK TAF...AS UNCERTAINTY ON TIMING
AND AREA TO GREAT TO MENTION AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CK
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1056 AM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 1054 AM CDT SUN JUL 7 2013
INTERESTING FORECAST FOR TODAY. WEAK UPPER WAVE GENERATING AN AREA
OF ELEVATED SHOWERS AND STORMS ACROSS CENTRAL SOUTH DAKOTA THIS
MORNING. AS THIS WAVE MOVES EAST OUR CWA WILL SEE WEAK UPPER FORCING
FOR ASCENT. EXPECT CIRRUS FROM THIS ACTIVITY TO WORK ITS WAY INTO
OUR WESTERN CWA AS WE HEAD INTO THIS AFTERNOON. MEANWHILE FRONTAL
BOUNDARY IS TAKING ITS SLOW TIME MOVING SOUTH ACROSS OUR CWA. SO
QUESTION BECOMES WHAT ARE OUR CONVECTION CHANCES THIS AFTERNOON. A
COUPLE THINGS TO WATCH WILL BE DEWPOINT EVOLUTION AND CONVECTIVE
EVOLUTION ACROSS CENTRAL AND WESTERN SOUTH DAKOTA.
MOISTURE POOLING BEHIND THE FRONT IS CURRENTLY ALLOWING DEWPOINTS TO
CREEP INTO THE LOW 70S IN SPOTS. A LOT OF GUIDANCE SUGGEST THESE
DEWPOINTS MAY STRUGGLE TO MIX OUT...WITH RELATIVELY DEEP MOISTURE
PRESENT UP TO ABOUT 850 MB...AND WEAK FLOW. AS TEMPERATURES RISE
INTO THE 80S THIS AFTERNOON...MLCAPE COULD END UP IN THE 2000 TO
3000 J/KG RANGE IN THE AREA OF MOISTURE POOLING. CIN WOULD ALSO
BECOME ALMOST ZERO. HOWEVER A VERY DRY LAYER AROUND 700 MB WILL
LIKELY HINDER UPDRAFTS SOMEWHAT...AND DESPITE THE BOUNDARY
NEARBY...SEE VERY LITTLE IN THE WAY OF LOW LEVEL CONVERGENCE OR
FORCING FOR ASCENT. SO IT WOULD COME DOWN TO WHETHER THE INSTABILITY
AND WEAK UPPER FORCING WOULD BE ENOUGH TO GET DEEP CU THROUGH THE
DRY AIR. HI RES GUIDANCE...SUCH AS THE 06Z WRF ARW AND 12Z 4KM NAM
BOTH SUGGEST THIS MAY HAPPEN. THUS WENT AHEAD AND ADDED IN A SLIGHT
CHANCE OF STORMS THIS AFTERNOON AND EVENING ACROSS PORTIONS OF OUR
CWA. AGAIN THIS IS REALLY DEPENDENT ON IF WE CAN KEEP DEWPOINTS IN
THE LOWER 70S. IF THEY FAIL TO MATERIALIZE...THEN DRY AIR ALOFT AND
WARM LAYER BETWEEN 800 AND 600 MB WILL LIKELY BE ENOUGH TO CAP
CONVECTION. WIND SHEAR IS WEAK...THUS ANY STORM WOULD BE PULSE OR
POSSIBLY MULTICELL TYPE. BUT GIVEN WHAT WOULD BE HIGH
INSTABILITY...WOULD EXPECT AT LEAST THE THREAT OF QUARTER SIZE HAIL
AND 60 MPH WIND GUSTS IN ANY STORM. HRRR DEVELOPS CONVECTION IN
CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND MOVES IT INTO OUR WESTERN
CWA LATER THIS AFTERNOON AND EVENING. GIVEN EXTENSIVE CLOUD COVER IN
THIS AREA...FEEL SURFACE BASED INITIATION IN CENTRAL SOUTH DAKOTA IS
UNLIKELY THIS AFTERNOON...THUS BELIEVE THE HRRR SOLUTION IS PROBABLY
NOT ACCURATE...AND SO WILL HOLD OFF ON ADDING IN ANY POPS IN OUR
WEST THROUGH 0Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SUN JUL 7 2013
TODAY AND MUCH OF TONIGHT SHOULD REMAIN QUIET IN OUR AREA DESPITE
MESSY...WAVE-RIDDLED MID LEVEL FLOW PATTERN BETWEEN DOMINANT RIDGE
BUILDING WESTWARD ACROSS THE SOUTHERN CONUS AND VARIOUS TROUGHS
TRACKING EASTWARD THROUGH THE CANADIAN PRAIRIES. IN THE NEAR TERM...
SEEING SOME ACCAS AND SPOTTY SHOWERS DEVELOP IN WESTERN IOWA AHEAD OF
WEAK WAVE. SHOWERS ARE NOT EXPECTED TO IMPACT OUR FORECAST AREA THIS
MORNING THOUGH COULD SEE A LITTLE OF THE ACCAS IN OUR FAR EAST EARLY
BEFORE WEAK WAVE PASSES BY. WEAK SURFACE BOUNDARY STILL WEST OF I-29
AS OF 08Z MOVING SOUTHEAST MORE SLOWLY THAN EXPECTED AT THIS TIME
YESTERDAY...THOUGH STILL EXPECTED TO MAKE SOME EASTWARD PROGRESS
THROUGH THE DAY...REACHING NEAR/JUST EAST OF HIGHWAY 60 CORRIDOR
IN NORTHWEST IOWA BY LATE AFTERNOON. WITH WEAK LOW LEVEL
FLOW...EXPECT HIGHER MOISTURE LEVELS TO POOL NEAR THE
BOUNDARY...WITH DEW POINTS IN NORTHWEST IOWA NEAR 70 WHILE
TEMPERATURES CLIMB INTO THE LOWER 90S THIS AFTERNOON. THIS SHOULD
LEAD TO FAIR AMOUNT OF INSTABILITY WHICH COULD POP A STRAY STORM
OR TWO WITH WEAK CONVERGENCE ALONG THE BOUNDARY TOWARD EVENING.
WILL HANG ONTO SLIGHT CHANCE FOR NOW...BUT IF SOME HIGH RES MODELS
SUCH AS RAP/HRRR TURN OUT TO BE ACCURATE IN THEIR DEPICTION OF DEW
POINTS MIXING MUCH LOWER THAN EXPECTED ACROSS OUR SOUTHEAST THIS
AFTERNOON...THEN CAP WOULD BE STRONGER AND WOULD NOT SEE ANY
DEVELOPMENT. WILL BE SOMETHING TO WATCH THROUGH THE DAY.
LATER TONIGHT...WILL BE LOOKING WESTWARD FOR POTENTIAL OF HIGH PLAINS
CONVECTION TO WORK TOWARD OUR WESTERN COUNTIES. STILL FAIR AMOUNT OF
INSTABILITY FOR STORMS TO WORK WITH AS THEY PUSH TOWARD THE MISSOURI
VALLEY AFTER MIDNIGHT. WILL CONTINUE TO CARRY CHANCE INTO AREAS ALONG
AND WEST OF THE JAMES VALLEY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 430 AM CDT SUN JUL 7 2013
IF STORMS DO WORK INTO THE WEST LATE TONIGHT...SHOULD SEE THEM LINGER
INTO THE MORNING HOURS ACROSS OUR WEST AND WILL HANG ONTO CHANCE WEST
OF I-29 FOR NOW. HOWEVER THIS PERIOD COULD JUST AS LIKELY BE DRY...AS
SOME MODELS INDICATING HIGH PLAINS CONVECTION WILL NOT SURVIVE THIS
FAR EAST. ALL-IN-ALL...LOW CONFIDENCE IN PRECIP CHANCES ACROSS OUR
WEST LATE TONIGHT/MONDAY MORNING. CONFIDENCE SOMEWHAT HIGHER THAT WE
WILL SEE DEVELOPMENT ACROSS OUR SOUTH BY MID-LATE AFTERNOON MONDAY...
AS WARM FRONT LIFTS BACK TO NEAR THE MISSOURI RIVER VALLEY AND MID
LEVEL HEIGHTS COLLAPSE IN ADVANCE OF APPROACHING WAVE. WITH LITTLE
FLOW NEAR THE BOUNDARY...SHOULD CONTINUE TO SEE LOW LEVEL MOISTURE
BUILD AND ENHANCE INSTABILITY. ALSO START TO SEE BETTER DEEP LAYER
SHEAR WORK INTO THE REGION...LOCALLY ENHANCED ALONG THE BOUNDARY. FOR
THIS REASON...MONDAY AFTERNOON/EVENING LOOKS TO HAVE FAIR POTENTIAL
FOR SEVERE STORMS AS WAVE /IN SOME MODELS/ SLIDES NORTHEAST ACROSS
THE FRONTAL BOUNDARY.
EVOLUTION OF PRECIP BEYOND THIS SOMEWHAT MUDDLED BY POTENTIAL FOR
LINGERING OUTFLOW BOUNDARIES...BUT GENERALLY EXPECT MOST MONDAY NIGHT
ACTIVITY TO WORK EAST OF THE FORECAST AREA BY EARLY TUESDAY. COLD
FRONT WILL BE PUSHING SOUTHEAST THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...AND EXPECT STRONG WARMING INTO THE LOWER TO MID 90S IN
THERMAL RIDGE AHEAD OF THE FRONT. HUMIDITY LINGERS AS WELL...WITH DEW
POINTS IN THE LOWER OR EVEN MID 70S POSSIBLE ACROSS MUCH OF THE AREA.
THIS WILL GIVE FRONT PLENTY OF INSTABILITY TO FEED ON...WITH STORM
DEVELOPMENT AIDED BY SOUTHERN EXTENT OF MAIN UPPER TROUGH WORKING
THROUGH THE NORTHERN PLAINS. WITH CURRENT FORECAST SPEED OF TROUGH
AND SURFACE BOUNDARY...STORMS SHOULD CLEAR MOST OF THE AREA BY 00Z
THOUGH WILL HOLD ONTO A CHANCE EAST OF HIGHWAY 60 INTO THE EVENING
SHOULD SYSTEM SLOW DOWN A BIT.
EARLIER PROJECTED DRY AND COOLER DAY FOR WEDNESDAY STILL ON SCHEDULE
BEHIND COLD FRONT...AS HIGH PRESSURE MOVES INTO THE NORTHERN PLAINS.
UPPER RIDGING UNANIMOUSLY PROGGED TO RETURN LATER IN THE WEEK WITH A
SLOW INCREASE IN TEMPERATURES AND HUMIDITY AS SURFACE HIGH MOVES
EAST OF OUR AREA. THE MAIN QUESTION IS HOW LONG IT WILL TAKE FOR A
THUNDERSTORM THREAT TO RETURN. WILL GO WITH A SLIGHT CHANCE
PROJECTED BY GUIDANCE FOR WEDNESDAY NIGHT FAR WEST AS WARM ADVECTION
QUICKLY BEGINS. OTHERWISE IT LOOKS LIKE FRIDAY WILL BE THE RETURN
DAY. THE THREAT MAY THEN DECREASE FOR SATURDAY AS THE UPPER RIDGE
BUILDS INTO OUR AREA. IN ANY EVENT WIDESPREAD PRECIPITATION SEEMS
UNLIKELY WHILE OUR LITTLE SHOT OF RELATIVELY COOL DRY WEATHER IS
FOLLOWED BY ANOTHER WARM UP. HOWEVER IT DOES NOT LOOK LIKE A RETURN
TO LAST SUMMERS HEAT WAVE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 638 AM CDT SUN JUL 7 2013
ISOLATED PATCHES OF 3-5SM BR WILL DISSIPATE BY 14Z. OTHERWISE
GENERA LY VFR THROUGH 08/09Z. ISOLATED TSRA EAST AND SOUTH OF FSD
07/00Z-06Z AND WEST OF MHE/HON 08/06Z-12Z WITH VERY LOCAL AND
BRIEF LOWERING OF CEILINGS TO 2-3K FEET AND VISIBILITIES TO 3-5SM
IN TSRA. EXPECTED COVERAGE OF CONVECTION TOO LIGHT TO INCLUDE IN
TAFS AT THIS TIME ESPECIALLY SINCE ALL IS EXPECTED AFTER 08/00Z.
AFT 08/09Z LCL VISIBILITIES 3-5SM/BR POSSIBLE BUT AGAIN EXPECTED
TO BE VERY PATCHY SO NOT AT THIS TIME INCLUDED IN TAF FORECASTS.
$$
SHORT TERM...
LONG TERM...
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1051 AM CDT SUN JUL 7 2013
.UPDATE...
MINOR ADJUSTMENTS TO FIRST PERIOD.
&&
.DISCUSSION...
MORNING SOUNDINGS INDICATE PW VALUES HAVE INCREASED BY .25 TO .5
INCHES ACROSS THE AREA AS COMPARED TO 24 HRS AGO. MOISTURE WILL
CONTINUE TO INCREASE AS THE UPPER LOW IN THE NWRN GULF PROGRESSES
ONSHORE LATER TODAY. ISOLATED SHOWERS AND THUNDERSTORMS HAVE
PUSHED INTO THE COASTAL PLAINS THIS MORNING...AND SHOULD INCREASE
IN COVERAGE ONCE DIURNAL HEATING BECOMES A FACTOR. ONGOING
FORECAST IS GENERALLY ON TRACK. ONLY MINOR ADJUSTMENTS WERE MADE
TO FIRST-PERIOD POPS/WX/QPF AND TEMPERATURES. NEW ZONES WILL BE
OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 641 AM CDT SUN JUL 7 2013/
UPDATE...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
A TROPICAL AIR MASS AND A MOSTLY ELEVATED LOW PRESSURE TROUGH
MOVING INTO THE TX COAST WILL DISRUPT THE OCCASIONAL MVFR CIG THIS
MORNING. WITH LIGHT WINDS AND BUOYANT AIR IN THE AREA...SCT LOW
BASED CUMULUS OF AROUND 1500 FT WILL HAVE TOPS LIFTING TO 10000 FT
OR HIGHER AS LIGHT SHOWERS BEGIN TO MOVE TOWARD THE I-35
TERMINALS. WILL LEAVE OUT MENTION OF MVFR CIGS UNTIL THE BETTER
CHANCE OF RAINS ARRIVE IN THE EARLY AFTERNOON HOURS AS DEPICTED BY
THE HRRR SIMULATED REFLECTIVITY. ANY FEEBLE ATTEMPT TO DEVELOP A
SURFACE CIRCULATION EAST OF BRO SHOULD BE HELD IN CHECK AS THE
UPPER SUPPORT PUSHES ONSHORE BY TONIGHT. THUS WILL PLAN ON A MORE
STEADY ONSHORE WIND BY TONIGHT...AND A MORE ROUTINE FORMATION OF
LOW CLOUDS AT AROUND 09Z. HIGH PWAT VALUES COULD SUPPORT
ADDITIONAL SHOWERS AROUND DAYBREAK...BUT WILL LEAVE OUT OF THE
LATE PERIODS OF THE TAFS UNTIL A BETTER TREND CAN BE ESTABLISHED.
PREV DISCUSSION... /ISSUED 322 AM CDT SUN JUL 7 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
A WEAKENED UPPER LEVEL INVERTED TROUGH FEATURE OVER THE WESTERN GULF
OF MEXICO WILL MIGRATE WEST ONTO THE TEXAS COASTAL PLAINS REGION
TODAY WITH AN ENHANCEMENT OF SEA BREEZE ACTIVITY LIKELY OVER
SOUTHERN AND EASTERN PORTIONS OF THE CWA. HIGH TEMPERATURES TODAY
WILL LOWER SLIGHTLY WITH THE INCREASING SURFACE BASED MOISTURE.
HIGHS TODAY WILL RANGE FROM THE LOW 90S ACROSS PORTIONS OF THE HILL
COUNTRY TO THE MID TO UPPER 90S ELSEWHERE. INCREASING CLOUDINESS
TONIGHT WITH A SLIGHT CHANCE OF MOSTLY EARLY EVENING SHOWERS AND
STORMS SOUTH AND EAST. LOWS IN THE 70S. THE UPPER TROUGH WILL MOVE
ACROSS THE AREA MONDAY WITH DEEP...MOIST TROPICAL EASTERLIES
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGHOUT MUCH OF
THE AREA. HIGHS MONDAY WILL MODERATE BACK INTO THE LOWER 90S MOST
LOCATIONS WITH NEAR 90 HILL COUNTRY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
SHOWERS AND STORMS WILL DIMINISH MONDAY EVENING AS THE INVERTED
UPPER TROUGH PUSHES DEEPER INTO MEXICO. LOWS MONDAY NIGHT AGAIN
MOSTLY IN THE 70S WITH NEAR 70 HILLS. UPPER LEVEL RIDGING WILL BUILD
BACK OVER THE REGION TUESDAY AND REMAIN STRONG THROUGH SATURDAY AS
THE CENTER OF THE HIGH SHIFTS EAST INTO THE SOUTHERN PLAINS BY LATE
IN THE WEEK. CONTINUED DEEP EASTERLIES HOWEVER IN THE MID AND LOWER
LEVELS OF THE ATMOSPHERE WILL ENHANCE SOME SEA BREEZE CONVECTION
INTO EASTERN SECTIONS BOTH TUESDAY AND WEDNESDAY. MORNING LOW CLOUDS
WILL BECOME PARTLY CLOUDY AFTERNOONS BOTH DAYS WITH HIGHS RANGING
FROM THE LOW 90S HILLS TO THE UPPER 90S TO NEAR 100 EASTERN SECTIONS.
LOWS IN THE 70S. ANOTHER EASTERLY WAVE FEATURE PUSHING ACROSS THE
COASTAL PLAINS THURSDAY WILL GENERATE MORE ACTIVITY OVER EASTERN
SECTIONS BOTH THURSDAY AND FRIDAY. HIGHS WILL CONTINUE NEAR OR
SLIGHTLY ABOVE SEASONAL NORMS THURSDAY THROUGH SATURDAY. LOWS
GENERALLY IN THE 70S EXCEPT UPPER 60S TO NEAR 70 HILLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 97 75 94 74 100 / 20 20 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 96 74 93 72 99 / 20 20 30 10 -
NEW BRAUNFELS MUNI AIRPORT 95 73 93 72 96 / 20 20 30 10 10
BURNET MUNI AIRPORT 94 74 91 73 96 / 10 10 20 10 -
DEL RIO INTL AIRPORT 97 76 92 75 94 / - - 30 20 10
GEORGETOWN MUNI AIRPORT 95 74 93 72 98 / 20 10 20 10 -
HONDO MUNI AIRPORT 96 74 90 73 96 / 20 10 30 20 -
SAN MARCOS MUNI AIRPORT 96 74 93 73 97 / 20 20 30 10 10
LA GRANGE - FAYETTE REGIONAL 94 76 92 75 99 / 40 20 30 10 20
SAN ANTONIO INTL AIRPORT 94 76 91 75 96 / 20 20 30 10 -
STINSON MUNI AIRPORT 95 74 92 73 94 / 20 20 30 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...25
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1006 AM CDT SUN JUL 7 2013
.UPDATE...
SCATTERED LIGHT SHOWERS TO COME ONSHORE THROUGH THE REMAINDER OF
THE MORNING...NO MORE THAN A FEW HUNDREDTHS TO A TENTH OF AN INCH
OF ACCUMULATION FROM MANY OF THESE QUICKLY NORTH-PASSING CELLS. AS
THE DAY HEATS UP INTO THE 90S...THIS 2 INCH PWAT AIR MASS OVER THE
COASTAL COUNTIES WILL CONTINUE TO CREEP FURTHER INLAND SO EXPECTING
PRECIPITATION TO BETTER FILL IN THROUGH THE EARLY EVENING. PROG
SOUNDINGS SHOW A NEAR-SATURATED COLUMN AS FAR NORTH AS THE CITY
BY TOMORROW MORNING. THUS...FEEL THAT AT LEAST HIGH END CHANCE
POPS ARE WARRANTED THROUGH TOMORROW AFTERNOON. WARM PROFILES MAKE
FOR SKINNY CAPES...LIMITED STORM COVERAGE. RELATIVELY LOWER AREAWIDE
(OVERALL) QPF DUE TO THE WIDELY-SCATTERED NATURE ON CONVECTION...
LOCALIZED POCKETS OF OVER AN INCH OVER THE SOUTHERN THIRD OF THE
CWA IS STILL NOT OUT OF THE QUESTION. 31
&&
.PREV DISCUSSION... /ISSUED 624 AM CDT SUN JUL 7 2013/
AVIATION...
SCATTERED SHOWERS ARE ONGOING ACROSS THE COASTAL COUNTIES THIS
MORNING AS THE LEADING EDGE OF DEEP TROPICAL MOISTURE MOVES
INLAND. GREATEST CONCERN WITH THIS ISSUANCE REMAINS TIMING AND
COVERAGE OF PRECIPITATION TODAY. EXPECT SCATTERED SHOWERS WITH A
FEW ISOLATED THUNDERSTORMS MIXED IN ACROSS THE SOUTHERN HALF OF
THE REGION. WILL CARRY PROB30 MENTION FOR METRO AREA TAF SITES FOR
LATE AFTERNOON AS CONFIDENCE IN TIMING A BIT TOO LOW FOR TEMPO AT
THIS TIME. GREATEST IMPACTS WILL BE TO LBX AND GLS WITH DECREASING
COVERAGE TO THE NORTH. 38
PREV DISCUSSION... /ISSUED 425 AM CDT SUN JUL 7 2013/
DISCUSSION...
LATEST RADAR IMAGERY SHOWS A LINE OF SHOWERS JUST REACHING THE
UPPER TX COAST THIS MORNING. THIS LINE OF SHOWERS APPEARS TO BE ON
THE LEADING EDGE OF HIGHER MOISTURE DELINEATED BY 2 INCH PRECIP
WATER VALUES NOTED ON GOES SOUNDER IMAGERY. UPPER LEVEL ANALYSIS
AND WATER VAPOR IMAGERY STILL SHOW A DEFORMING SHEAR AXIS WHICH
SEEMS TO BE IN THE PROCESS OF WEAKENING. PRESSURE GRADIENT AT THE
SFC HAS INCREASED SO GETTING SOME DECENT LOW LEVEL FLOW OFF THE
GULF WHICH SHOULD CONTINUE TO ADVECT HIGHER MOISTURE INLAND TODAY.
FOR THE MOST PART...GFS/ECMWF MODELS CONTINUE TO SHOW HIGHER
MOISTURE MOVE INTO SE TX THIS MORNING AND THROUGH THE EARLY
AFTERNOON. THE LATEST HRRR RUNS SEEMS TO SUPPORT THIS WITH
CONVECTION DEVELOPING INLAND MAINLY AROUND 15-16Z AND CONTINUING
THROUGH 22-23Z THIS AFTERNOON. ACTIVITY LOOKS MORE SCT IN NATURE
SO BACKED OFF ON POPS A TOUCH. STILL HAVE 60 POPS FOR THE I-10
CORRIDOR INCLUDING MOST OF HOUSTON. HEAVY RAINFALL THREAT WILL
LARGELY DEPEND ON INDIVIDUAL CELLS THAT BECOME STRONG AND FULLY
TAP DEEPER MOISTURE. GFS SHOWS PRECIP WATER VALUES GETTING TO
AROUND 2-2.2 INCHES WHICH WILL SUPPORT MODERATE TO HEAVY RAINFALL.
AGAIN MAIN FLOOD THREAT WILL BE URBAN IN NATURE WITH STORMS THAT
CAN QUICKLY PRODUCE 2 INCHES IN AN HOUR. OTHERWISE DRY GROUNDS
SHOULD BE ABLE TO ABSORB A LOT OF THE RUN OFF AND NOT CONTRIBUTE
TO FLOODING. WITH MOISTURE SLOWLY PUSHING INTO THE AREA...ALSO
INCREASED MAX TEMPS A COUPLE OF DEGREES AS CLOUD COVER WILL BE
SLOW TO FILL IN ACROSS THE AREA. LOOK FOR 1.8-2 INCH PW VALUES TO
REMAIN OVER SE TX THROUGH MONDAY SO WENT WITH 40/50 POPS FOR
SCATTERED ACTIVITY DURING THE DAY. AGAIN MOST OF THIS ACTIVITY
WILL BE DIURNALLY DRIVEN SO WILL HAVE LOWER POPS OVERNIGHT.
RAINFALL AMOUNTS AGAIN EXPECTED TO BE CONFINED TO THE COAST.
HOUSTON AREA MAY GET WIDE SPREAD HALF INCH AMOUNTS BUT THAT WILL
BE PUSHING IT. NORTH OF HOUSTON EXPECT RAINFALL AMOUNTS TO REALLY
DROP OFF AND AREAS FROM CONROE TO COLLEGE STATION MAY NOT SEE ANY
RAINFALL. BY AND LARGE THINK AREAS NORTH OF HOUSTON WILL AT MOST
GET 0.1-0.25 INCHES WITH 0.5-1 INCH AMOUNTS ALONG THE COAST. STILL
THINK HIGHEST MOISTURE WILL BE OFF TO THE EAST OVER LOUISIANA SO
RAINFALL AMOUNTS OF AN INCH OR MORE WILL BE IN THE GULF EASTWARD
THROUGH LOUISIANA. STILL DO NOT WANT TO RULE OUT A QUICK 2-3
INCHES IN SOME STRONGER CONVECTION BUT THINK THESE STORMS WILL BE
REALLY LOCALIZED AND NOT THE NORM.
IT LOOKS LIKE HIGHER MOISTURE OF 1.6-2 INCH PRECIP WATER VALUES
WILL LINGER TUE/WED SO WILL KEEP SOME 20/30 POPS IN THE FORECAST
FOR MAINLY AFTERNOON STORMS. MOISTURE DOES DECREASE THUR THROUGH
SAT SO HAVE POPS TAPERING OFF FROM 20 PERCENT TO NO RAIN CHANCES.
UPPER LEVEL PATTERN ALSO UNDERGOES SOME CHANGES DURING THIS TIME.
UPPER LEVEL RIDGE CURRENTLY OVER THE S ROCKIES REMAINS WEAK AND
NOT WELL ESTABLISHED FOR THE BEGINNING OF THE WEEK. BY THE END OF
THE WEEK THE RIDGE STRENGTHENS OVER THE C ROCKIES WITH ANOTHER
AMPLIFIED TROUGH OVER THE MID ATLANTIC BY FRIDAY. RIDGE WILL KEEP
LOWER THICKNESS HEIGHTS EAST OF THE AREA SO COULD SEE TEMPS
CREEPING UP TO UPPER 90S TO NEAR 100 FOR THE END OF THE WEEK.
TEMPS AT 850MB WHEN MIXED DOWN AT LEAST SUPPORT TEMPS IN THE UPPER
90S ACROSS THE AREA.
39
MARINE...
SCATTERED SHOWERS ARE MOVING THROUGH THE COASTAL WATERS THIS
MORNING ALONG THE LEADING EDGE OF DEEPER TROPICAL MOISTURE THAT
WILL CONTINUE TO PUSH INTO SOUTHEAST TEXAS TODAY. EXPECT SCATTERED
SHOWERS WITH PERHAPS AN ISOLATED THUNDERSTORM THROUGH MONDAY
ACROSS THE COASTAL WATERS. LIGHT TO MODERATE SOUTHEASTERLY WINDS
WILL CONTINUE THROUGH THE NEXT SEVERAL DAYS. WITH THE EASTERLY
COMPONENT TO THE WINDS WE WILL CONTINUE TO SEE TIDE LEVELS AROUND
1 TO 1.5 FEET ABOVE NORMAL VALUES. RIP CURRENTS WILL ALSO REMAIN
PROBLEMATIC FOR AREA BEACHES THROUGH THE WEEKEND. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 76 95 76 98 / 30 20 30 20 10
HOUSTON (IAH) 92 77 94 77 96 / 60 30 50 20 20
GALVESTON (GLS) 89 82 90 82 92 / 50 50 50 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 PM CDT THIS
AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...31
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
641 AM CDT SUN JUL 7 2013
.UPDATE...
SEE AVIATION FOR 12Z TAF DISCUSSION.
&&
.AVIATION...
A TROPICAL AIR MASS AND A MOSTLY ELEVATED LOW PRESSURE TROUGH
MOVING INTO THE TX COAST WILL DISRUPT THE OCCASIONAL MVFR CIG THIS
MORNING. WITH LIGHT WINDS AND BUOYANT AIR IN THE AREA...SCT LOW
BASED CUMULUS OF AROUND 1500 FT WILL HAVE TOPS LIFTING TO 10000 FT
OR HIGHER AS LIGHT SHOWERS BEGIN TO MOVE TOWARD THE I-35
TERMINALS. WILL LEAVE OUT MENTION OF MVFR CIGS UNTIL THE BETTER
CHANCE OF RAINS ARRIVE IN THE EARLY AFTERNOON HOURS AS DEPICTED BY
THE HRRR SIMULATED REFLECTIVITY. ANY FEEBLE ATTEMPT TO DEVELOP A
SURFACE CIRCULATION EAST OF BRO SHOULD BE HELD IN CHECK AS THE
UPPER SUPPORT PUSHES ONSHORE BY TONIGHT. THUS WILL PLAN ON A MORE
STEADY ONSHORE WIND BY TONIGHT...AND A MORE ROUTINE FORMATION OF
LOW CLOUDS AT AROUND 09Z. HIGH PWAT VALUES COULD SUPPORT
ADDITIONAL SHOWERS AROUND DAYBREAK...BUT WILL LEAVE OUT OF THE
LATE PERIODS OF THE TAFS UNTIL A BETTER TREND CAN BE ESTABLISHED.
&&
.PREV DISCUSSION... /ISSUED 322 AM CDT SUN JUL 7 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
A WEAKENED UPPER LEVEL INVERTED TROUGH FEATURE OVER THE WESTERN GULF
OF MEXICO WILL MIGRATE WEST ONTO THE TEXAS COASTAL PLAINS REGION
TODAY WITH AN ENHANCEMENT OF SEA BREEZE ACTIVITY LIKELY OVER
SOUTHERN AND EASTERN PORTIONS OF THE CWA. HIGH TEMPERATURES TODAY
WILL LOWER SLIGHTLY WITH THE INCREASING SURFACE BASED MOISTURE.
HIGHS TODAY WILL RANGE FROM THE LOW 90S ACROSS PORTIONS OF THE HILL
COUNTRY TO THE MID TO UPPER 90S ELSEWHERE. INCREASING CLOUDINESS
TONIGHT WITH A SLIGHT CHANCE OF MOSTLY EARLY EVENING SHOWERS AND
STORMS SOUTH AND EAST. LOWS IN THE 70S. THE UPPER TROUGH WILL MOVE
ACROSS THE AREA MONDAY WITH DEEP...MOIST TROPICAL EASTERLIES
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGHOUT MUCH OF
THE AREA. HIGHS MONDAY WILL MODERATE BACK INTO THE LOWER 90S MOST
LOCATIONS WITH NEAR 90 HILL COUNTRY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
SHOWERS AND STORMS WILL DIMINISH MONDAY EVENING AS THE INVERTED
UPPER TROUGH PUSHES DEEPER INTO MEXICO. LOWS MONDAY NIGHT AGAIN
MOSTLY IN THE 70S WITH NEAR 70 HILLS. UPPER LEVEL RIDGING WILL BUILD
BACK OVER THE REGION TUESDAY AND REMAIN STRONG THROUGH SATURDAY AS
THE CENTER OF THE HIGH SHIFTS EAST INTO THE SOUTHERN PLAINS BY LATE
IN THE WEEK. CONTINUED DEEP EASTERLIES HOWEVER IN THE MID AND LOWER
LEVELS OF THE ATMOSPHERE WILL ENHANCE SOME SEA BREEZE CONVECTION
INTO EASTERN SECTIONS BOTH TUESDAY AND WEDNESDAY. MORNING LOW CLOUDS
WILL BECOME PARTLY CLOUDY AFTERNOONS BOTH DAYS WITH HIGHS RANGING
FROM THE LOW 90S HILLS TO THE UPPER 90S TO NEAR 100 EASTERN SECTIONS.
LOWS IN THE 70S. ANOTHER EASTERLY WAVE FEATURE PUSHING ACROSS THE
COASTAL PLAINS THURSDAY WILL GENERATE MORE ACTIVITY OVER EASTERN
SECTIONS BOTH THURSDAY AND FRIDAY. HIGHS WILL CONTINUE NEAR OR
SLIGHTLY ABOVE SEASONAL NORMS THURSDAY THROUGH SATURDAY. LOWS
GENERALLY IN THE 70S EXCEPT UPPER 60S TO NEAR 70 HILLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 97 75 94 74 100 / 10 20 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 97 74 93 72 99 / 10 20 30 10 -
NEW BRAUNFELS MUNI AIRPORT 95 73 93 72 96 / 10 20 30 10 10
BURNET MUNI AIRPORT 95 74 91 73 96 / - 10 20 10 -
DEL RIO INTL AIRPORT 96 76 92 75 94 / - - 30 20 10
GEORGETOWN MUNI AIRPORT 95 74 93 72 98 / 10 10 20 10 -
HONDO MUNI AIRPORT 95 74 90 73 96 / - 10 30 20 -
SAN MARCOS MUNI AIRPORT 96 74 93 73 97 / 10 20 30 10 10
LA GRANGE - FAYETTE REGIONAL 95 76 92 75 99 / 40 20 30 10 20
SAN ANTONIO INTL AIRPORT 95 76 91 75 96 / 10 20 30 10 -
STINSON MUNI AIRPORT 95 74 92 73 94 / 10 20 30 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...02
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
628 AM CDT SUN JUL 7 2013
.AVIATION...
WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE DRIFTING
ACROSS THE SOUTH PLAINS EARLY THIS MORNING. ODDS OF A DIRECT
IMPACT AT KLBB ARE LOW BUT NOT ZERO AND GIVEN THAT A SMALL STORM
RECENTLY DEVELOPED ABOUT 12 MILES WEST OF THE TERMINAL HAVE
DECIDED TO INSERT A VCTS MENTION AT KLBB IN THE SHORT TERM.
OUTSIDE OF ANY STORMS...EXPECT VFR CONDITIONS TO PREVAIL WITH
SOUTHERLY WINDS...THOUGH AT WEAKER LEVELS THAN THE PAST TWO
AFTERNOONS. AFTERNOON CONVECTION SHOULD REMAIN WELL WEST OF THE
TERMINALS IN NEW MEXICO.
&&
.PREV DISCUSSION... /ISSUED 343 AM CDT SUN JUL 7 2013/
SHORT TERM...
DIRTY SOUTHWESTERN RIDGE HAS EXPANDED TO ENCOMPASS WEST TEXAS AND
THIS WILL PROVIDE ANOTHER TOASTY JULY DAY WITH HIGHS SIMILAR TO
SATURDAY. MID-LEVEL MOISTURE SPILLING OVER THE SOUTH PLAINS COUPLED
WITH WEAK ELEVATED INSTABILITY...DEEP LAYER MOISTURE CONVERGENCE AND
ELEVATED FRONTOGENESIS WERE SUPPORTING A FEW RECENTLY DEVELOPED
SHOWERS AND STORMS ACROSS THE FAR NORTHWESTERN ZONES. THIS ACTIVITY
WAS NOT MOVING MUCH THANKS TO WEAK STEERING FLOW/WINDS WITHIN THE
RIDGE...BUT WE COULD SEE AT LEAST ISOLATED ACTIVITY HANG ON ACROSS
THE WESTERN ZONES AND PERHAPS EXPAND/DEVELOP TOWARD THE I-27/US-87
CORRIDOR AS THE RECENT RAP AND HRRR RUNS SUGGEST. HENCE HAVE
INSERTED A SLIGHT CHANCE OF THUNDERSTORMS INTO THE GRIDS ACROSS THE
WESTERN AND INTO THE CENTRAL ZONES IN THE 12-18Z TIME-FRAME. ANY
ACTIVITY WILL LIKELY WANE TOWARD MID TO LATE MORNING. STRONG HEATING
AND SUFFICIENT MOISTURE WILL THEN YIELD ANOTHER ROUND OF CONVECTION
OVER THE HIGHER TERRAIN OF NM AND CO THIS AFTERNOON...BUT SIMILAR TO
SATURDAY...THIS ACTIVITY WILL NOT HAVE MUCH INCENTIVE TO MOVE VERY
FAR EASTWARD AND SHOULD STAY WELL WEST OF THE CWA. THE MID-LEVEL
MOISTURE PLUME WILL STILL EXTEND IN CLOSE PROXIMITY TO THE FAR
NORTHWESTERN ZONES LATE TONIGHT AND THERE MAY BE SOME RISK OF LATE
NIGHT ELEVATED CONVECTIVE DEVELOPMENT LIKE WE HAVE SEEN THE LAST
COUPLE OF NIGHTS. HOWEVER THE MID-LEVEL MOISTURE PLUME IS PROGGED TO
THIN/DRY A BIT LOCALLY AND LOW-LEVEL FORCING APPEARS LESS...SO HAVE
KEPT THE FORECAST DRY FOR TONIGHT. OTHERWISE...IT WILL BE ANOTHER
MILD NIGHT WITH LOWS VARYING FROM THE MID-60S NORTHWEST TO LOWER AND
MIDDLE 70S EAST.
LONG TERM...
AN UPPER LEVEL RIDGE...CENTERED ROUGHLY OVER THE 4-CORNERS INITIALLY...
AND GRADUALLY MIGRATING INTO THE CENTRAL HIGH PLAINS...WILL KEEP
THE FA HOT AND DRY FOR THE MOST PART THIS UPCOMING WEEK.
OROGRAPHICALLY FORCED CONVECTION WITHIN MOISTURE PLUME TRAPPED IN
THE RIDGE SHOULD REMAIN TO OUR WEST MONDAY WHILE AN INVERTED
TROUGH MOVING WEST ACROSS THE BIG BEND WILL BE OF LITTLE
CONSEQUENCE TO OUR WX. WE ARE STILL WATCHING FOR A TEMPORARY
WEAKNESS TO DEVELOP IN THE EASTERN PART OF THE RIDGE WED/THU AS A
SHORTWAVE MOVES FROM THE CANADIAN PRAIRIES TO THE GREAT LAKES AND
A COLD FRONT DIPS INTO SRN CO/SW KS. BUT ANY TSTM ACTIVITY
ASSOCIATED WITH THIS WAVE/FRONT APPEARS UNLIKELY TO MAKE IT INTO
OUR NRN ZONES LATE WED/EARLY THU. THEN...AS THE UPPER RIDGE RE-
EXPANDS E-NEWD WE EXPECT TEMPS TO NUDGE UPWARD A FEW DEGREES
HEADING INTO NEXT WEEKEND. EARLY NEXT WEEK...THE UPPER RIDGE MAY
START TO RETROGRADE BACK TO THE WEST AS AN UPPER TROUGH/LOW
DEVELOPS IN THE DEEP SOUTH. WE ARE COUNTING ON THIS PATTERN CHANGE
TO BRING A COOLING TREND AND PERHAPS A CHANCE OF RAIN NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 92 66 93 66 95 / 20 10 10 10 10
TULIA 94 67 95 68 96 / 20 10 10 10 10
PLAINVIEW 93 67 95 69 95 / 20 10 10 10 10
LEVELLAND 94 68 94 70 94 / 20 10 10 10 10
LUBBOCK 95 70 95 70 95 / 20 10 10 10 10
DENVER CITY 94 68 93 69 93 / 20 10 10 10 10
BROWNFIELD 95 69 94 70 95 / 20 10 10 10 0
CHILDRESS 99 71 98 74 99 / 0 0 0 0 0
SPUR 97 71 96 72 97 / 0 0 0 0 0
ASPERMONT 98 72 97 74 99 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
23/33/23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
624 AM CDT SUN JUL 7 2013
.DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION
&&
.AVIATION...
SCATTERED SHOWERS ARE ONGOING ACROSS THE COASTAL COUNTIES THIS
MORNING AS THE LEADING EDGE OF DEEP TROPICAL MOISTURE MOVES
INLAND. GREATEST CONCERN WITH THIS ISSUANCE REMAINS TIMING AND
COVERAGE OF PRECIPITATION TODAY. EXPECT SCATTERED SHOWERS WITH A
FEW ISOLATED THUNDERSTORMS MIXED IN ACROSS THE SOUTHERN HALF OF
THE REGION. WILL CARRY PROB30 MENTION FOR METRO AREA TAF SITES FOR
LATE AFTERNOON AS CONFIDENCE IN TIMING A BIT TOO LOW FOR TEMPO AT
THIS TIME. GREATEST IMPACTS WILL BE TO LBX AND GLS WITH DECREASING
COVERAGE TO THE NORTH. 38
&&
.PREV DISCUSSION... /ISSUED 425 AM CDT SUN JUL 7 2013/
DISCUSSION...
LATEST RADAR IMAGERY SHOWS A LINE OF SHOWERS JUST REACHING THE
UPPER TX COAST THIS MORNING. THIS LINE OF SHOWERS APPEARS TO BE ON
THE LEADING EDGE OF HIGHER MOISTURE DELINEATED BY 2 INCH PRECIP
WATER VALUES NOTED ON GOES SOUNDER IMAGERY. UPPER LEVEL ANALYSIS
AND WATER VAPOR IMAGERY STILL SHOW A DEFORMING SHEAR AXIS WHICH
SEEMS TO BE IN THE PROCESS OF WEAKENING. PRESSURE GRADIENT AT THE
SFC HAS INCREASED SO GETTING SOME DECENT LOW LEVEL FLOW OFF THE
GULF WHICH SHOULD CONTINUE TO ADVECT HIGHER MOISTURE INLAND TODAY.
FOR THE MOST PART...GFS/ECMWF MODELS CONTINUE TO SHOW HIGHER
MOISTURE MOVE INTO SE TX THIS MORNING AND THROUGH THE EARLY
AFTERNOON. THE LATEST HRRR RUNS SEEMS TO SUPPORT THIS WITH
CONVECTION DEVELOPING INLAND MAINLY AROUND 15-16Z AND CONTINUING
THROUGH 22-23Z THIS AFTERNOON. ACTIVITY LOOKS MORE SCT IN NATURE
SO BACKED OFF ON POPS A TOUCH. STILL HAVE 60 POPS FOR THE I-10
CORRIDOR INCLUDING MOST OF HOUSTON. HEAVY RAINFALL THREAT WILL
LARGELY DEPEND ON INDIVIDUAL CELLS THAT BECOME STRONG AND FULLY
TAP DEEPER MOISTURE. GFS SHOWS PRECIP WATER VALUES GETTING TO
AROUND 2-2.2 INCHES WHICH WILL SUPPORT MODERATE TO HEAVY RAINFALL.
AGAIN MAIN FLOOD THREAT WILL BE URBAN IN NATURE WITH STORMS THAT
CAN QUICKLY PRODUCE 2 INCHES IN AN HOUR. OTHERWISE DRY GROUNDS
SHOULD BE ABLE TO ABSORB A LOT OF THE RUN OFF AND NOT CONTRIBUTE
TO FLOODING. WITH MOISTURE SLOWLY PUSHING INTO THE AREA...ALSO
INCREASED MAX TEMPS A COUPLE OF DEGREES AS CLOUD COVER WILL BE
SLOW TO FILL IN ACROSS THE AREA. LOOK FOR 1.8-2 INCH PW VALUES TO
REMAIN OVER SE TX THROUGH MONDAY SO WENT WITH 40/50 POPS FOR
SCATTERED ACTIVITY DURING THE DAY. AGAIN MOST OF THIS ACTIVITY
WILL BE DIURNALLY DRIVEN SO WILL HAVE LOWER POPS OVERNIGHT.
RAINFALL AMOUNTS AGAIN EXPECTED TO BE CONFINED TO THE COAST.
HOUSTON AREA MAY GET WIDE SPREAD HALF INCH AMOUNTS BUT THAT WILL
BE PUSHING IT. NORTH OF HOUSTON EXPECT RAINFALL AMOUNTS TO REALLY
DROP OFF AND AREAS FROM CONROE TO COLLEGE STATION MAY NOT SEE ANY
RAINFALL. BY AND LARGE THINK AREAS NORTH OF HOUSTON WILL AT MOST
GET 0.1-0.25 INCHES WITH 0.5-1 INCH AMOUNTS ALONG THE COAST. STILL
THINK HIGHEST MOISTURE WILL BE OFF TO THE EAST OVER LOUISIANA SO
RAINFALL AMOUNTS OF AN INCH OR MORE WILL BE IN THE GULF EASTWARD
THROUGH LOUISIANA. STILL DO NOT WANT TO RULE OUT A QUICK 2-3
INCHES IN SOME STRONGER CONVECTION BUT THINK THESE STORMS WILL BE
REALLY LOCALIZED AND NOT THE NORM.
IT LOOKS LIKE HIGHER MOISTURE OF 1.6-2 INCH PRECIP WATER VALUES
WILL LINGER TUE/WED SO WILL KEEP SOME 20/30 POPS IN THE FORECAST
FOR MAINLY AFTERNOON STORMS. MOISTURE DOES DECREASE THUR THROUGH
SAT SO HAVE POPS TAPERING OFF FROM 20 PERCENT TO NO RAIN CHANCES.
UPPER LEVEL PATTERN ALSO UNDERGOES SOME CHANGES DURING THIS TIME.
UPPER LEVEL RIDGE CURRENTLY OVER THE S ROCKIES REMAINS WEAK AND
NOT WELL ESTABLISHED FOR THE BEGINNING OF THE WEEK. BY THE END OF
THE WEEK THE RIDGE STRENGTHENS OVER THE C ROCKIES WITH ANOTHER
AMPLIFIED TROUGH OVER THE MID ATLANTIC BY FRIDAY. RIDGE WILL KEEP
LOWER THICKNESS HEIGHTS EAST OF THE AREA SO COULD SEE TEMPS
CREEPING UP TO UPPER 90S TO NEAR 100 FOR THE END OF THE WEEK.
TEMPS AT 850MB WHEN MIXED DOWN AT LEAST SUPPORT TEMPS IN THE UPPER
90S ACROSS THE AREA.
39
MARINE...
SCATTERED SHOWERS ARE MOVING THROUGH THE COASTAL WATERS THIS
MORNING ALONG THE LEADING EDGE OF DEEPER TROPICAL MOISTURE THAT
WILL CONTINUE TO PUSH INTO SOUTHEAST TEXAS TODAY. EXPECT SCATTERED
SHOWERS WITH PERHAPS AN ISOLATED THUNDERSTORM THROUGH MONDAY
ACROSS THE COASTAL WATERS. LIGHT TO MODERATE SOUTHEASTERLY WINDS
WILL CONTINUE THROUGH THE NEXT SEVERAL DAYS. WITH THE EASTERLY
COMPONENT TO THE WINDS WE WILL CONTINUE TO SEE TIDE LEVELS AROUND
1 TO 1.5 FEET ABOVE NORMAL VALUES. RIP CURRENTS WILL ALSO REMAIN
PROBLEMATIC FOR AREA BEACHES THROUGH THE WEEKEND. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 75 95 75 97 / 30 20 30 20 10
HOUSTON (IAH) 93 76 94 76 96 / 60 30 50 20 20
GALVESTON (GLS) 88 80 90 81 90 / 50 50 50 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION...CORRECTED
NWS ALBANY NY
123 PM EDT SUN JUL 7 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL BEGIN TO WEAKEN AND MOVE A LITTLE FURTHER
SOUTHEAST THROUGH THIS AFTERNOON. THIS WILL ALLOW MOISTURE TO
MOVE BACK INTO THE REGION...INCREASING THE RISK OF SHOWERS AND
THUNDERSTORMS. TONIGHT INTO MONDAY...AN UPPER LEVEL DISTURBANCE
WILL MOVE BACK INTO FROM THE OHIO VALLEY...KEEPING OUR WEATHER
UNSETTLED.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS AND THUNDERSTORMS ARE DEVELOPING WITH QUITE A BIT OF
INSTABILITY OVER THE REGION. FREEZING LEVELS AND -20C LEVELS QUITE
HIGH...BUT THERE COULD BE A STORM OR TWO THAT COULD PRODUCE SOME
STRONG GUSTY WINDS...AND HEAVY RAIN IS ALWAYS A THREAT WITH
LOCALIZED FLASH FLOODING. JUST SOME MINOR ADJUSTMENTS TO THE
TEMPERATURES AND RAIN CHANCES THROUGH THIS AFTERNOON.
THE LOCAL WRF AND HRRR SUGGEST AN ACTIVE AFTERNOON AND EVENING
ACROSS THE REGION.
HEAT INDICES IN THE MID HUDSON VALLEY AND NW CT WILL TOUCH 100 AT
TIMES THIS AFTERNOON BUT NOT WIDESPREAD ENOUGH OR LONG ENOUGH
DURATION FOR A SHORT FUSE HEAT ADVISORY. HEAT INDICES HAVE BEEN
NEAR 100 THE PAST COUPLE OF AFTERNOONS AND HEAT INDICES A DEGREE
OR TWO WARMER THIS AFTERNOON SHOULD FEEL NEARLY THE SAME AS THE
PAST COUPLE OF AFTERNOONS.
PREVIOUS DISCUSSION DESCRIBES THE FACTORS AFFECTING CONVECTION
THIS AFTERNOON AND EVENING AND IS BELOW..
QUITE AN INSTABILITY GRADIENT HAS ALREADY SET UP ACROSS THE
AREA...SINCE LOCATIONS TO THE SOUTH OF ALBANY DID NOT HAVE ANY
CLOUDS/SHOWERS MOVE THROUGH EARLIER AND INSTEAD HAD SUNSHINE.
COMBINED WITH A RETURN IN LOW LEVEL MOISTURE...THIS HAS ALLOW
SBCAPE VALUES TO SURGE IN TO THE 2000-3000 J/KG RANGE LATE THIS
MORNING. TO THE NORTH A RATHER SHARP INSTABILITY GRADIENT NOW
EXISTS...ALTHOUGH IT WILL BECOME SOMEWHAT MORE UNIFORM BY EARLY
AFTERNOON DUE TO PARTIAL SUNSHINE HEATING THIS AREA AS WELL.
HOWEVER...THE INSTABILITY GRADIENT AND DIFFERENTIAL HEATING THAT
OCCURRED MAY RESULT IN AN AREA TO WATCH FOR ENHANCED CONVECTION BY
EARLY TO MID AFTERNOON. ANOTHER SOURCE OF ASCENT COULD BE A
SUBTLE IMPULSE MOVING NORTHEASTWARD FROM THE UPPER LOW OVER THE
OHIO VALLEY...THAT COULD TRACK THROUGH PA/NY THIS AFTERNOON AND
EVENING. SO KEPT MENTION OF SCATTERED THUNDERSTORMS WITH
RELATIVELY HIGH POPS OF 5O PERCENT. MESOSCALE MODELS SHOWING
CONVECTION INITIATING ACROSS MUCH OF THE AREA THIS AFTERNOON...AND
SOME STORMS COULD BE STRONG BASED ON HOW TALL UPDRAFTS ARE ABLE
TO GET.
DEEP LAYER SHEAR AROUND 25-35 KT IS SUFFICIENT FOR STORM
ORGANIZATION...ALTHOUGH ONCE AGAIN MID LEVEL LAPSE RATES REMAIN
RATHER MARGINAL AROUND 6.0 C/KM AND HIGH FREEZING LEVELS OVER 14
KFT. WITH MODERATE TO HIGH LEVELS OF INSTABILITY...WILL HAVE TO
WATCH FOR WET MICROBURST POTENTIAL AND ONCE AGAIN HEAVY RAIN AND
POSSIBLE ISOLATED FLASH FLOODING WITH THE STRONGER AND SLOW MOVING
T-STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WHILE THE AFOREMENTIONED DISTURBANCES WILL MOVE ON BY THIS
EVENING...THE ACTUAL UPPER AIR LOW LOOKS TO MOVE OUR WAY LATE
TONIGHT INTO MONDAY. THIS WILL SERVE TO COOL THE ATMOSPHERE A LITTLE
BUT THE WIND FIELD (BULK SHEAR) LOOKS WEAK. SHOWERS AND STORMS LOOK
TO DIMINISH IN AREA DURING THE EVENING...BUT COULD REKINDLE LATER
OVERNIGHT INTO EARLY MONDAY. LOWS OVERNIGHT WILL BE MUGGY...65 TO 70
DEGREES.
WE EXPECT PLENTY OF CLOUDS AROUND WITH THIS FEATURE INTO MONDAY
WHICH DESPITE A SLIGHTLY COOLER MID LEVEL ATMOSPHERE...SHOULD ONCE
AGAIN KEEP THUNDERSTORMS FROM THE MOST PART GETTING STRONG OR
SEVERE. PWATS LOOK TO INCREASE SLIGHTLY...REACHING NEARLY 2 INCHES.
THE BIGGER CONCERN WITH THE THUNDERSTORMS ON MONDAY WOULD BE THE
POTENTIAL FOR EXCESSIVE RAINFALL. THERE THE POTENTIAL FOR SLOW
MOVING THUNDERSTORMS TO PRODUCE RAINFALL EXCEEDING ONE-HOUR FLASH
FLOOD GUIDANCE OF ONLY 1-2 INCHES ACROSS REGION.
WHILE IT IS TOO EARLY TO ISSUE A FLASH FLOOD WATCH WE WILL CONTINUE
TO HIGHLIGHT THIS POTENTIAL IN OUR HAZARDOUS WEATHER OUTLOOK
PRODUCT.
WITH THE CLOUDS AND EXPECTED SHOWERS AND STORMS ON
MONDAY...TEMPERATURES WILL NOT BE AS HIGH AS THEY HAVE
BEEN...TOPPING OUT 80-85 MOST VALLEY LOCATIONS...70S HIGHER TERRAIN.
HOWEVER...IT WILL CERTAINLY REMAIN VERY HUMID.
MONDAY NIGHT...LINGERING SHOWERS AND THUNDERSTORMS SHOULD DIMINISH
AS THE UPPER AIR LOW OPENS AND FLEES TO THE EAST. PARTIAL CLEARING
WILL ALLOW TEMPERATURES TO DIP A LITTLE LOWER...60 TO 65 DEGREES
MOST PLACES...WITH A FEW UPPER 50S ACROSS THE ADIRONDACK PARK.
TUESDAY...OPTIMISTICALLY LOOKS LIKE A MAINLY DRY DAY AS SLIGHTLY
DRIER AIR WORKS INTO THE REGION VIA WEAK SUBSIDENCE. STILL...DECIDED
TO ASSIGN SLIGHT POPS DURING THE AFTERNOON AS THERE WILL BE SOME
INSTABILITY AND PRESUMABLY LOTS OF LOW LEVEL MOISTURE EVAPORATING
FROM THE GROUND. SUNSHINE WILL RETURN TO HELP BOOST TEMPERATURES TO
BETWEEN 85 AND 90 DEGREES IN MOST AREAS.
IT LOOKS MAINLY DRY TUESDAY NIGHT...BUT BY WEDNESDAY...THE NEXT
DISTURBANCE IN THE NORTHERN STREAM APPROACHES...BRINGING YET ANOTHER
INCREASING THREAT IN SHOWERS AND THUNDERSTORMS. LOWS WILL GENERALLY
BE IN THE 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE PERIOD STARTS OUT WEDNESDAY WITH A WARM FRONT AND/OR PRE-FRONTAL
TROUGH APPROACHING THE AREA FROM THE GREAT LAKES AND OHIO VALLEY.
THIS SYSTEM WILL BRING SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS. THE EVENTUAL INTENSITY OF T-STORMS WILL DEPEND ON THE
DEGREE OF INSTABILITY...WHICH WILL BE TIED TO CLOUD COVER. THERE
SHOULD BE DECENT FLOW ALOFT FOR MID JULY WITH A MIGRATORY SUB-1000MB
CYCLONE TRACKING EASTWARD ACROSS NEAR HUDSON BAY.
THE ASSOCIATED COLD FRONT WILL PASS THROUGH THE REGION SOMETIME
WEDNESDAY NIGHT...AND THEN BECOME NEARLY STATIONARY TO THE SOUTH OF
THE REGION THURSDAY. POPS WILL BE FORECAST TO DECREASE FROM AROUND
50 PERCENT WEDNESDAY NIGHT...TO 30 TO 40 PERCENT ON THURSDAY. ONLY
20 PERCENT POPS ARE FORECAST THURSDAY NIGHT AND DRY WEATHER FOR
FRIDAY AS THE UPPER LEVEL WAVE FORMS A CLOSED/CUTOFF LOW TO OUR
SOUTHWEST...AND FOR A BRIEF TIME DRIER AIR MOVES INTO THE REGION.
THE DRIER AIR WILL BE SHORT-LOVED AS THE UPPER LOW EVENTUALLY
INDUCES THE MOISTURE ALONG THE FRONT TO SURGE NORTHWARD AGAIN FRIDAY
NIGHT AND SATURDAY WITH A CHANCE OF SHOWERS.
AFTER WEDNESDAY...TEMPERATURES AND HUMIDITY LEVELS WILL START TO
DROP OFF SOMEWHAT AS A COOLER NORTHERLY FLOW DEVELOPS IN WAKE OF THE
COLD FRONT. HIGHS WEDNESDAY WILL BE IN THE UPPER 70S AND 80S...IN
THE MID 70S TO MID 80S THURSDAY...IN THE MID 70S TO LOWER 80S FRIDAY
AND SATURDAY. LOWS WEDNESDAY NIGHT WILL BE IN THE MID 60S TO LOWER
70S...THE UPPER 50S AND 60S THURSDAY NIGHT...AND THE MID 50S TO MID
60S FRIDAY NIGHT.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
PREDOMINATELY VFR CONDITIONS WILL PREVAIL AT THE TAF SITES THIS
AFTERNOON MINUS ANY SHOWER/THUNDERSTORM ASSOCIATED MVFR/IFR FLYING
CONDITIONS. HAVE ONLY MENTIONED VCSH IN THE TAFS AT THIS TIME AS
COVERAGE WILL REMAIN SCATTERED AT BEST AND WILL AMEND AS NEEDED.
LATEST RADAR IMAGERY DEPICTS SCATTERED SHOWERS/THUNDERSTORMS
DEVELOPING ACROSS THE REGION AND THESE WILL PERSIST THROUGH THE
EVENING HOURS. ANY CONVECTION SHOULD DIMINISH BY MIDNIGHT WITH A
BRIEF LULL IN PRECIPITATION AHEAD OF THE NEXT APPROACHING SYSTEM.
INCREASING CLOUD COVER SHOULD LIMIT FOG POTENTIAL SOMEWHAT TONIGHT
BUT WILL CONTINUE WITH MVFR FOG FOR ALL TAF SITES EXCEPT KALB. AN
UPPER-LEVEL SHORTWAVE TROUGH AND SURFACE FRONTAL BOUNDARY WILL
APPROACH THE REGION TONIGHT AND MONDAY BRINGING ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS TO THE TAF SITES TO END THE TAF PERIOD.
SURFACE WINDS WILL BECOME SOUTH OR SOUTHWEST AT 5 TO 10 KTS...THEN
BECOME LIGHT AGAIN AFTER SUNSET.
OUTLOOK...
TUE...MAINLY VFR. SCT -SHRA/-TSRA.
WED...VFR/MVFR/IFR DUE TO SCT TO NUM -SHRA/-TSRA.
THU-FRI...MAINLY VFR. SCT PM -SHRA/-TSRA.
MVFR/IFR OVERNIGHT FOG POSSIBLE TUE-FRI.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
AFTER A BRIEF BREAK IN THE ACTION ON SATURDAY...IT LOOKS AS IF
SCATTERED SHOWERS AND THUNDERSTORMS RETURN TODAY AND AGAIN TOMORROW.
SOME OF THESE ESPECIALLY ON MONDAY COULD PRODUCE LOCALLY HEAVY
RAINFALL. TUESDAY LOOKS DRIER BUT THEN MORE SHOWERS COULD TAKE PLACE
ON WEDNESDAY.
NORMAL RH RECOVERIES EACH NIGHT BETWEEN 80 TO 100 PERCENT WILL ALLOW
FOR WIDESPREAD DEW FORMATION. DAYTIME RH VALUES WILL GENERALLY BE IN
THE 40 TO 60 PERCENT RANGE.
&&
.HYDROLOGY...
THE MOHAWK RIVER AT UTICA CONTINUES TO EXPERIENCE MINOR FLOODING.
THE RIVER AND CREEK FLOWS NEAR THE WEST CENTRAL MOHAWK RIVER ARE
EXPECTED TO GRADUALLY RECEDE INTO THE WEEKEND...UNLESS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS OCCUR OVER OR NEAR THE BASIN.
THERE WILL BE SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY DURING
THE AFTERNOON AND EVEN MORE COVERAGE OF SHOWERS AND THUNDERSTORMS
MONDAY WITH THE APPROACH OF A WEAK COLD FRONT AND UPPER AIR LOW
PRESSURE SYSTEM. A MOIST AND HUMID AIR MASS WILL ALLOW ANY SHOWER OR
THUNDERSTORM TO BE CAPABLE OF PRODUCING LOCALLY HEAVY
DOWNPOURS...AND A QUICK INCH OR MORE OF RAINFALL DUE TO THE
ANOMALOUS PRECIPITABLE WATER VALUES...ESPECIALLY ON MONDAY.
THERE WILL BE A CONTINUED THREAT FOR ISOLATED FLASH FLOODING...AS
WELL AS FLOODING OF POOR DRAINAGE AND LOW LYING AREAS. NO FLASH
FLOOD WATCHES ARE BEING ISSUED DUE TO THE EXPECTED ISOLATED NATURE
OF ANY FLOODING. IT IS ALSO DIFFICULT TO DETERMINE WHERE THE
HEAVIEST RAINFALL WILL OCCUR.
WHILE ADDITIONAL FLOODING IS NOT ANTICIPATED ON ANY MAIN STEM RIVER
POINTS...LOCALLY SHARP RISES ARE POSSIBLE DUE TO ANY CONVECTION THAT
MAY OCCUR OVER THE NEXT SEVERAL DAYS...ESPECIALLY FOR THOSE POINTS
THAT ARE MORE FLASHIER IN NATURE.
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...HWJIV/NAS
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...IRL
FIRE WEATHER...HWJIV
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
122 PM EDT SUN JUL 7 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL BEGIN TO WEAKEN AND MOVE A LITTLE FURTHER
SOUTHEAST THROUGH THIS AFTERNOON. THIS WILL ALLOW MOISTURE TO
MOVE BACK INTO THE REGION...INCREASING THE RISK OF SHOWERS AND
THUNDERSTORMS. TONIGHT INTO MONDAY...AN UPPER LEVEL DISTURBANCE
WILL MOVE BACK INTO FROM THE OHIO VALLEY...KEEPING OUR WEATHER
UNSETTLED.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS AND THUNDERSTORMS ARE DEVELOPING WITH QUITE A BIT OF
INSTABILITY OVER THE REGION. FREEZING LEVELS ADN -20C LEVELS QUITE
HIGH...BUT THERE COULD BE A STORM OR TWO THAT COULD PRODUCE SOME
STRONG GUSTY WINDS...AND HEAVY RAIN IS ALWAYS A THREAT WITH
LOCALIZED FLASH FLOODING. JUST SOME MINOR ADJUSTMENTS TO THE
TEMPERATURES AND RAIN CHANCES THROUGH THIS AFTERNOON.
THE LOCAL WRF AND HRRR SUGGEST AN ACTIVE AFTERNOON AND EVENING
ACROSS THE REGION.
HEAT INDICES IN THE MID HUDSON VALLEY AND NW CT WILL TOUCH 100 AT
TIMES THIS AFTERNOON BUT NOT WIDESPREAD ENOUGH OR LONG ENOUGH
DURATION FOR A SHORT FUSE HEAT ADVISORY. HEAT INDICES HAVE BEEN
NEAR 100 THE PAST COUPLE OF AFTERNOONS AND HEAT INDICES A DEGREE
OR TWO WARMER THIS AFTERNOON SHOULD FEEL NEARLY THE SAME AS THE
PAST COUPLE OF AFTERNOONS.
PREVIOUS DISCUSSION DESCRIBES THE FACTORS AFFECTING CONVECTION
THIS AFTERNOON AND EVENING AND IS BELOW..
QUITE AN INSTABILITY GRADIENT HAS ALREADY SET UP ACROSS THE
AREA...SINCE LOCATIONS TO THE SOUTH OF ALBANY DID NOT HAVE ANY
CLOUDS/SHOWERS MOVE THROUGH EARLIER AND INSTEAD HAD SUNSHINE.
COMBINED WITH A RETURN IN LOW LEVEL MOISTURE...THIS HAS ALLOW
SBCAPE VALUES TO SURGE IN TO THE 2000-3000 J/KG RANGE LATE THIS
MORNING. TO THE NORTH A RATHER SHARP INSTABILITY GRADIENT NOW
EXISTS...ALTHOUGH IT WILL BECOME SOMEWHAT MORE UNIFORM BY EARLY
AFTERNOON DUE TO PARTIAL SUNSHINE HEATING THIS AREA AS WELL.
HOWEVER...THE INSTABILITY GRADIENT AND DIFFERENTIAL HEATING THAT
OCCURRED MAY RESULT IN AN AREA TO WATCH FOR ENHANCED CONVECTION BY
EARLY TO MID AFTERNOON. ANOTHER SOURCE OF ASCENT COULD BE A
SUBTLE IMPULSE MOVING NORTHEASTWARD FROM THE UPPER LOW OVER THE
OHIO VALLEY...THAT COULD TRACK THROUGH PA/NY THIS AFTERNOON AND
EVENING. SO KEPT MENTION OF SCATTERED THUNDERSTORMS WITH
RELATIVELY HIGH POPS OF 5O PERCENT. MESOSCALE MODELS SHOWING
CONVECTION INITIATING ACROSS MUCH OF THE AREA THIS AFTERNOON...AND
SOME STORMS COULD BE STRONG BASED ON HOW TALL UPDRAFTS ARE ABLE
TO GET.
DEEP LAYER SHEAR AROUND 25-35 KT IS SUFFICIENT FOR STORM
ORGANIZATION...ALTHOUGH ONCE AGAIN MID LEVEL LAPSE RATES REMAIN
RATHER MARGINAL AROUND 6.0 C/KM AND HIGH FREEZING LEVELS OVER 14
KFT. WITH MODERATE TO HIGH LEVELS OF INSTABILITY...WILL HAVE TO
WATCH FOR WET MICROBURST POTENTIAL AND ONCE AGAIN HEAVY RAIN AND
POSSIBLE ISOLATED FLASH FLOODING WITH THE STRONGER AND SLOW MOVING
T-STORMS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WHILE THE AFOREMENTIONED DISTURBANCES WILL MOVE ON BY THIS
EVENING...THE ACTUAL UPPER AIR LOW LOOKS TO MOVE OUR WAY LATE
TONIGHT INTO MONDAY. THIS WILL SERVE TO COOL THE ATMOSPHERE A LITTLE
BUT THE WIND FIELD (BULK SHEAR) LOOKS WEAK. SHOWERS AND STORMS LOOK
TO DIMINISH IN AREA DURING THE EVENING...BUT COULD REKINDLE LATER
OVERNIGHT INTO EARLY MONDAY. LOWS OVERNIGHT WILL BE MUGGY...65 TO 70
DEGREES.
WE EXPECT PLENTY OF CLOUDS AROUND WITH THIS FEATURE INTO MONDAY
WHICH DESPITE A SLIGHTLY COOLER MID LEVEL ATMOSPHERE...SHOULD ONCE
AGAIN KEEP THUNDERSTORMS FROM THE MOST PART GETTING STRONG OR
SEVERE. PWATS LOOK TO INCREASE SLIGHTLY...REACHING NEARLY 2 INCHES.
THE BIGGER CONCERN WITH THE THUNDERSTORMS ON MONDAY WOULD BE THE
POTENTIAL FOR EXCESSIVE RAINFALL. THERE THE POTENTIAL FOR SLOW
MOVING THUNDERSTORMS TO PRODUCE RAINFALL EXCEEDING ONE-HOUR FLASH
FLOOD GUIDANCE OF ONLY 1-2 INCHES ACROSS REGION.
WHILE IT IS TOO EARLY TO ISSUE A FLASH FLOOD WATCH WE WILL CONTINUE
TO HIGHLIGHT THIS POTENTIAL IN OUR HAZARDOUS WEATHER OUTLOOK
PRODUCT.
WITH THE CLOUDS AND EXPECTED SHOWERS AND STORMS ON
MONDAY...TEMPERATURES WILL NOT BE AS HIGH AS THEY HAVE
BEEN...TOPPING OUT 80-85 MOST VALLEY LOCATIONS...70S HIGHER TERRAIN.
HOWEVER...IT WILL CERTAINLY REMAIN VERY HUMID.
MONDAY NIGHT...LINGERING SHOWERS AND THUNDERSTORMS SHOULD DIMINISH
AS THE UPPER AIR LOW OPENS AND FLEES TO THE EAST. PARTIAL CLEARING
WILL ALLOW TEMPERATURES TO DIP A LITTLE LOWER...60 TO 65 DEGREES
MOST PLACES...WITH A FEW UPPER 50S ACROSS THE ADIRONDACK PARK.
TUESDAY...OPTIMISTICALLY LOOKS LIKE A MAINLY DRY DAY AS SLIGHTLY
DRIER AIR WORKS INTO THE REGION VIA WEAK SUBSIDENCE. STILL...DECIDED
TO ASSIGN SLIGHT POPS DURING THE AFTERNOON AS THERE WILL BE SOME
INSTABILITY AND PRESUMABLY LOTS OF LOW LEVEL MOISTURE EVAPORATING
FROM THE GROUND. SUNSHINE WILL RETURN TO HELP BOOST TEMPERATURES TO
BETWEEN 85 AND 90 DEGREES IN MOST AREAS.
IT LOOKS MAINLY DRY TUESDAY NIGHT...BUT BY WEDNESDAY...THE NEXT
DISTURBANCE IN THE NORTHERN STREAM APPROACHES...BRINGING YET ANOTHER
INCREASING THREAT IN SHOWERS AND THUNDERSTORMS. LOWS WILL GENERALLY
BE IN THE 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE PERIOD STARTS OUT WEDNESDAY WITH A WARM FRONT AND/OR PRE-FRONTAL
TROUGH APPROACHING THE AREA FROM THE GREAT LAKES AND OHIO VALLEY.
THIS SYSTEM WILL BRING SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS. THE EVENTUAL INTENSITY OF T-STORMS WILL DEPEND ON THE
DEGREE OF INSTABILITY...WHICH WILL BE TIED TO CLOUD COVER. THERE
SHOULD BE DECENT FLOW ALOFT FOR MID JULY WITH A MIGRATORY SUB-1000MB
CYCLONE TRACKING EASTWARD ACROSS NEAR HUDSON BAY.
THE ASSOCIATED COLD FRONT WILL PASS THROUGH THE REGION SOMETIME
WEDNESDAY NIGHT...AND THEN BECOME NEARLY STATIONARY TO THE SOUTH OF
THE REGION THURSDAY. POPS WILL BE FORECAST TO DECREASE FROM AROUND
50 PERCENT WEDNESDAY NIGHT...TO 30 TO 40 PERCENT ON THURSDAY. ONLY
20 PERCENT POPS ARE FORECAST THURSDAY NIGHT AND DRY WEATHER FOR
FRIDAY AS THE UPPER LEVEL WAVE FORMS A CLOSED/CUTOFF LOW TO OUR
SOUTHWEST...AND FOR A BRIEF TIME DRIER AIR MOVES INTO THE REGION.
THE DRIER AIR WILL BE SHORT-LOVED AS THE UPPER LOW EVENTUALLY
INDUCES THE MOISTURE ALONG THE FRONT TO SURGE NORTHWARD AGAIN FRIDAY
NIGHT AND SATURDAY WITH A CHANCE OF SHOWERS.
AFTER WEDNESDAY...TEMPERATURES AND HUMIDITY LEVELS WILL START TO
DROP OFF SOMEWHAT AS A COOLER NORTHERLY FLOW DEVELOPS IN WAKE OF THE
COLD FRONT. HIGHS WEDNESDAY WILL BE IN THE UPPER 70S AND 80S...IN
THE MID 70S TO MID 80S THURSDAY...IN THE MID 70S TO LOWER 80S FRIDAY
AND SATURDAY. LOWS WEDNESDAY NIGHT WILL BE IN THE MID 60S TO LOWER
70S...THE UPPER 50S AND 60S THURSDAY NIGHT...AND THE MID 50S TO MID
60S FRIDAY NIGHT.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
PREDOMINATELY VFR CONDITIONS WILL PREVAIL AT THE TAF SITES THIS
AFTERNOON MINUS ANY SHOWER/THUNDERSTORM ASSOCIATED MVFR/IFR FLYING
CONDITIONS. HAVE ONLY MENTIONED VCSH IN THE TAFS AT THIS TIME AS
COVERAGE WILL REMAIN SCATTERED AT BEST AND WILL AMEND AS NEEDED.
LATEST RADAR IMAGERY DEPICTS SCATTERED SHOWERS/THUNDERSTORMS
DEVELOPING ACROSS THE REGION AND THESE WILL PERSIST THROUGH THE
EVENING HOURS. ANY CONVECTION SHOULD DIMINISH BY MIDNIGHT WITH A
BRIEF LULL IN PRECIPITATION AHEAD OF THE NEXT APPROACHING SYSTEM.
INCREASING CLOUD COVER SHOULD LIMIT FOG POTENTIAL SOMEWHAT TONIGHT
BUT WILL CONTINUE WITH MVFR FOG FOR ALL TAF SITES EXCEPT KALB. AN
UPPER-LEVEL SHORTWAVE TROUGH AND SURFACE FRONTAL BOUNDARY WILL
APPROACH THE REGION TONIGHT AND MONDAY BRINGING ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS TO THE TAF SITES TO END THE TAF PERIOD.
SURFACE WINDS WILL BECOME SOUTH OR SOUTHWEST AT 5 TO 10 KTS...THEN
BECOME LIGHT AGAIN AFTER SUNSET.
OUTLOOK...
TUE...MAINLY VFR. SCT -SHRA/-TSRA.
WED...VFR/MVFR/IFR DUE TO SCT TO NUM -SHRA/-TSRA.
THU-FRI...MAINLY VFR. SCT PM -SHRA/-TSRA.
MVFR/IFR OVERNIGHT FOG POSSIBLE TUE-FRI.
&&
.FIRE WEATHER...
NO FIRE WEATHER ISSUES ARE EXPECTED OVER THE NEXT SEVERAL DAYS.
AFTER A BRIEF BREAK IN THE ACTION ON SATURDAY...IT LOOKS AS IF
SCATTERED SHOWERS AND THUNDERSTORMS RETURN TODAY AND AGAIN TOMORROW.
SOME OF THESE ESPECIALLY ON MONDAY COULD PRODUCE LOCALLY HEAVY
RAINFALL. TUESDAY LOOKS DRIER BUT THEN MORE SHOWERS COULD TAKE PLACE
ON WEDNESDAY.
NORMAL RH RECOVERIES EACH NIGHT BETWEEN 80 TO 100 PERCENT WILL ALLOW
FOR WIDESPREAD DEW FORMATION. DAYTIME RH VALUES WILL GENERALLY BE IN
THE 40 TO 60 PERCENT RANGE.
&&
.HYDROLOGY...
THE MOHAWK RIVER AT UTICA CONTINUES TO EXPERIENCE MINOR FLOODING.
THE RIVER AND CREEK FLOWS NEAR THE WEST CENTRAL MOHAWK RIVER ARE
EXPECTED TO GRADUALLY RECEDE INTO THE WEEKEND...UNLESS ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS OCCUR OVER OR NEAR THE BASIN.
THERE WILL BE SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY DURING
THE AFTERNOON AND EVEN MORE COVERAGE OF SHOWERS AND THUNDERSTORMS
MONDAY WITH THE APPROACH OF A WEAK COLD FRONT AND UPPER AIR LOW
PRESSURE SYSTEM. A MOIST AND HUMID AIR MASS WILL ALLOW ANY SHOWER OR
THUNDERSTORM TO BE CAPABLE OF PRODUCING LOCALLY HEAVY
DOWNPOURS...AND A QUICK INCH OR MORE OF RAINFALL DUE TO THE
ANOMALOUS PRECIPITABLE WATER VALUES...ESPECIALLY ON MONDAY.
THERE WILL BE A CONTINUED THREAT FOR ISOLATED FLASH FLOODING...AS
WELL AS FLOODING OF POOR DRAINAGE AND LOW LYING AREAS. NO FLASH
FLOOD WATCHES ARE BEING ISSUED DUE TO THE EXPECTED ISOLATED NATURE
OF ANY FLOODING. IT IS ALSO DIFFICULT TO DETERMINE WHERE THE
HEAVIEST RAINFALL WILL OCCUR.
WHILE ADDITIONAL FLOODING IS NOT ANTICIPATED ON ANY MAIN STEM RIVER
POINTS...LOCALLY SHARP RISES ARE POSSIBLE DUE TO ANY CONVECTION THAT
MAY OCCUR OVER THE NEXT SEVERAL DAYS...ESPECIALLY FOR THOSE POINTS
THAT ARE MORE FLASHIER IN NATURE.
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...HWJIV/NAS
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...IRL
FIRE WEATHER...HWJIV
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
219 PM EDT SUN JUL 7 2013
.PREV DISCUSSION... /ISSUED 730 AM EDT SUN JUL 7 2013/
PREV DISCUSSION... /ISSUED 355 AM EDT SUN JUL 7 2013/
SHORT TERM /TODAY THROUGH MONDAY/...
WATER VAPOR LOOP CONTINUES TO SHOW DEEP MOISTURE BEING FUNNELED INTO
W GA FROM THE TROPICS. PWATS HAVE BUMPED BACK UP TO AROUND 2 INCHES
ACROSS NORTHERN GA ACCORDING TO THE 00Z FFC SOUNDING. MODELS SHOW
THIS HIGH MOISTURE AXIS REMAINING ACROSS THE CWFA THROUGH TONIGHT.
SOMEWHAT DRIER AIR HAS MOVED IN ACROSS THE EASTERN PORTION OF THE
CWFA.
UPPER LOW ACROSS THE OHIO VALLEY WILL SLOWLY EJECT INTO THE MIDDLE
ATLANTIC BY EARLY MONDAY MORNING. MEANWHILE...THE BERMUDA HIGH AT
THE SURFACE WILL BEGIN TO BUILD WESTWARD...ALSO HELPING SHIFT THE
TROPICAL PLUME WESTWARD. THIS SHOULD RESULT IN A DECREASE IN
PWATS/MOISTURE CONTENT DURING THE DAY ON MONDAY.
LATEST RUNS OF THE HRRR SHOW THE BEST CHANCE FOR POPS IS IN NW GA
THIS MORNING. THIS SEEMS REASONABLE AS PRECIP AXIS HAS NOT MOVED
MOST OF THE NIGHT. SCT/NMRS SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS THE REMAINDER OF THE CWFA THIS AFT/EVE BUT THEY SHOULD BE
MORE DIURNALLY DRIVEN.
FFG IS LESS THAN AN INCH AND A HALF ACROSS AREAS MOSTLY NORTH OF THE
FALL LINE. WILL NOT MAKE ANY CHANGES TO THE FLOOD WATCH FOR NOW.
NLISTEMAA
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
EXTENDED BEGINS WITH UPPER WAVE MOVING OFF THE NEW ENGLAND COAST
WHILE CLOSED LOW OVER THE BAHAMAS IS WORKING ITS WAY WEST...AND
BETWEEN THESE TWO THE ATLANTIC HIGH IS RIDGING INTO THE SOUTHEAST.
THE EXITING SYSTEM ACROSS NEW ENGLAND ALLOWS THE ASSOCIATED
SURFACE BOUNDARY/FRONT TO ELONGATE AND STRETCH ACROSS THE
SOUTHEAST. BEST PRECIP CHANCES WILL BE ACROSS NORTH GEORGIA.
ANOTHER LONGWAVE TROUGH PUSHES INTO SOUTHERN CANADA AND THE UPPER
MISSISSIPPI VALLEY BY MIDWEEK AND WITH CONTINUE SOUTHERLY FLOW
FROM THE ATLANTIC AND GULF...PRECIP CHANCES INCREASE AGAIN
WEDNESDAY AND ESPECIALLY INTO THURSDAY AS THE TROUGH DIGS INTO THE
OHIO VALLEY AND A SURFACE FRONT MOVES INTO THE TENNESSEE VALLEY.
REALLY REMARKABLE AGREEMENT BETWEEN THE GFS AND ECMWF THROUGH THIS
PERIOD...THOUGH THE ECMWF IS A TAD DEEPER WITH THE WAVE INTO THE
SOUTHEAST AND A LITTLE BIT MORE NEGATIVELY TILTED.
LATE IN THE WORK WEEK THIS TROUGH CONTINUES TO DIG AND DEEPEN INTO
THE GREAT LAKES...EVENTUALLY FORMING A CUTOFF LOW OVER THE UPPER
OHIO VALLEY. GFS A LITTLE FASTER WITH THIS TRANSITION BUT STILL
PRETTY SIMILAR IN OVERALL DEPICTION. TROUGH AXIS PROGGED TO BE
GENERALLY ACROSS THE MIDDLE OF THE STATE...THUS REDUCING PRECIP
CHANCES ACROSS NORTHWEST GEORGIA BUT KEEPING POPS IN SOUTHEAST
ZONES. THE LOW CONTINUES TO DEEPEN AND DIG TO THE SOUTHWEST...
RETROGRADING IN RESPONSE TO DEEPENING UPPER HIGH OVER THE DESERT
SOUTHWEST AND WESTERN PLAINS. BY THE END OF THE PERIOD THE CUTOFF
LOW IS SOMEWHERE EITHER IN THE TENNESSEE VALLEY OR SOUTHEAST...
WITH BOTH MODELS CONTINUING TO RETROGRADE IT TO THE WEST BEYOND
THE END OF THE PERIOD. SO IN GENERAL...IT LOOKS LIKE NEXT WEEK
COULD BE A REPEAT OF WHAT WE SAW THIS PAST WEEK WITH SIGNIFICANT
MOISTURE TRANSPORT OUT OF THE GULF. WILL WAIT AND SEE HOW THIS
PLAYS OUT.
TEMPS REMAIN AT OR BELOW NORMAL THROUGH THE PERIOD. IF WE HAVE TO
PUT UP WITH ALL THE RAIN AND POTENTIAL FLOODING...AT LEAST WE GET
COOLER TEMPS OUT OF IT. HOWEVER...THERE IS A LARGER CONCERN THAT
WITH THIS CONTINUED WET PATTERN WE COULD BE SETTING THE STAGE FOR
SOME REAL PROBLEMS IF WE GET A TROPICAL SYSTEM MOVING IN.
TDP
&&
.AVIATION...
18Z UPDATE...
MOSTLY LIGHT RAIN ACROSS THE AREA RIGHT NOW WITH VFR TO MVFR
CEILINGS AND VSBYS. THIS LIGHT RAIN IS EXPECTED TO CONTINUE THROUGH
THE FORECAST PERIOD. THE RAIN WILL DIMINISH SOME OVER NIGHT BUT
RETURN AGAIN MONDAY. WINDS ARE OUT OF THE SW AND SHOULD TURN TO
THE SE AFTER 00Z. WINDS WILL GO BACK TO THE SW MONDAY AFTER
16-18Z. WINDS SPEEDS WILL STAY IN THE 5-10KT RANGE. CEILINGS AND
VSBYS SHOULD STAY IN THE VFR TO MVFR RANGE.
//ATL CONFIDENCE...18Z
UPDATE... CONFIDENCE MEDIUM ON ALL ELEMENTS.
01
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 82 70 86 71 / 70 50 50 30
ATLANTA 81 70 84 72 / 70 40 50 30
BLAIRSVILLE 75 67 78 66 / 70 50 60 30
CARTERSVILLE 80 69 86 69 / 70 40 60 30
COLUMBUS 84 73 89 73 / 70 30 50 20
GAINESVILLE 79 68 83 71 / 70 50 60 30
MACON 86 73 88 72 / 70 30 50 20
ROME 80 70 86 70 / 70 50 60 30
PEACHTREE CITY 81 70 84 70 / 70 40 50 30
VIDALIA 89 72 90 72 / 50 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR THE FOLLOWING ZONES:
BANKS...BARROW...BARTOW...CARROLL...CATOOSA...CHATTOOGA...
CHEROKEE...CLARKE...CLAYTON...COBB...COWETA...DADE...DAWSON...
DEKALB...DOUGLAS...FANNIN...FAYETTE...FLOYD...FORSYTH...GILMER...
GORDON...GREENE...GWINNETT...HALL...HARALSON...HEARD...HENRY...
JACKSON...LUMPKIN...MADISON...MORGAN...MURRAY...NEWTON...NORTH
FULTON...OCONEE...OGLETHORPE...PAULDING...PICKENS...POLK...
ROCKDALE...SOUTH FULTON...TALIAFERRO...TOWNS...UNION...WALKER...
WALTON...WHITE...WHITFIELD...WILKES.
&&
$$
SHORT TERM...01
LONG TERM....41
AVIATION...01
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1257 PM MDT SUN JUL 7 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1254 PM MDT SUN JUL 7 2013
LATEST WV IMAGERY AND RAP ANALYSIS SHOW H5 RIDGE STILL IN PLACE
ACROSS SOUTHERN PLAINS WITH SERIES OF WEAK SHORTWAVE TROUGHS
ROTATING AROUND WESTERN AND NORTHERN EXTENT OF RIDGE THROUGH
WESTERLY FLOW. AT THE SURFACE A COLD FRONT HAS STALLED ALONG THE
KS/NE BORDER WITH A SURFACE TROUGH EXTENDING SOUTH ALONG THE KS/CO
BORDER.
A WEAK SHORTWAVE TROUGH EXPECTED TO DROP SOUTH OUT OF WESTERN
NEBRASKA LATE THIS AFTERNOON AND TONIGHT WILL COMBINE WITH THESE
SURFACE FEATURES TO INITIATE SCATTERED THUNDERSTORMS ACROSS THE CWA.
PRIMARY FOCUS SHOULD BE ALONG FRONT WHERE HIGH TD VALUES NORTH OF
THE FRONT HAVE RESULTED IN ML CAPE 1000-1500 J/KG AS OF THE LATEST
RAP ANALYSIS. BETTER DEEP SHEER IS EXPECTED TO BE IN PLACE NORTH OF
THE FRONT WHERE 0-6KM BULK SHEER AROUND 35KT BY 00Z COULD SUPPORT A
SEVERE WIND AND HAIL THREAT. THERE IS LESS INSTABILITY AND MORE CIN
TO OVERCOME FURTHER SOUTH ALONG THE SURFACE TROUGH...HOWEVER AS
DAYTIME HEATING CONTINUES AND THE SHORTWAVE TROUGH MOVES SOUTH WE
SHOULD BE ABLE TO SEE AT LEAST ISOLATED THUNDERSTORMS DEVELOPING
ALONG THE SURFACE TROUGH THIS AFTERNOON/EVENING. PWAT VALUES
1.2-1.3" REPRESENT AN ANOMALOUSLY WET ATMOSPHERE FOR THIS TIME OF
YEAR...AND AS WAS THE CASE YESTERDAY MANY OF THESE STORMS WILL BE
SLOW MOVERS...SO HEAVY RAIN WILL BE A CONCERN WHERE STORMS DEVELOP.
LEE TROUGH IS EXPECTED TO BEGIN TO DEEPEN LATE TONIGHT WITH LLJ
BUILDING ACROSS THE NE HALF OF THE CWA. WITH INCREASING ISENTROPIC
ASCENT AND H85 SUPPORT WE COULD SEE LINGERING THUNDERSTORMS IN
PROXIMITY OF THE FRONTAL ZONE ACROSS OUR NE CWA...SO I KEPT ISO
THUNDER MENTION MOST OF THE NIGHT FOR THOSE LOCATIONS. THERE IS
SOME INDICATION WITH VERY MOIST E-NE BL FLOW OF FOG DEVELOPING IN
SW NEBRASKA...HOWEVER WITH BL LIKELY MIXED WITH LLJ INCREASING AND
FRONT POSSIBLY SHIFTING NORTH I WASNT CONFIDENT ENOUGH TO ADD
MENTION.
DESPITE LARGE SCALE FORCING IN PLACE MONDAY IT DOES LOOK LIKE A
TROUGH AXIS/DRYLINE ALONG KS/CO BORDER COULD HELP INITIATE
THUNDERSTORMS BY THE AFTERNOON WITH INSTABILITY BUILDING ACROSS THE
EASTERN CWA. I WASNT CONFIDENT ENOUGH TO ADD MORE THAN SLIGHT CHANCE
MENTION AT THIS POINT. H85 TEMPS ARE ACTUALLY ADVERTISED TO BE 2-3C
WARMER THAN THE LAST FEW DAYS WHEN HIGHS HAVE BEEN AROUND 100F...SO
WE COULD BE LOOKING AT NEAR RECORD HIGH TEMPS ACROSS THE CWA MONDAY
WITH VALUES IN THE 100S ACROSS THE AREA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 1251 PM MDT SUN JUL 7 2013
AN UPPER RIDGE CENTERED OVER THE SOUTHERN ROCKIES WILL BE THE
DOMINATING INFLUENCE THROUGH THE LONG TERM PERIOD. TEMPERATURES
WILL BE ABOVE NORMAL...ALTHOUGH A WEAK COLD FRONT ON TUESDAY WILL
KNOCK TEMPERATURES DOWN A FEW DEGREES THROUGH THURSDAY...THEY WILL
WARM AGAIN FOR THE LATE WEEK AND WEEKEND. POSITION OF THE RIDGE
EARLY IN THE PERIOD WILL BE CLOSER TO THE FOUR CORNERS AND ALLOW
SHORTWAVE TROUGHS ROTATING AROUND IT TO BRING A CHANCE FOR SCATTERED
THUNDERSTORMS. AS THE RIDGE BUILDS EASTWARD LATER IN THE
WEEK...THUNDERSTORM CHANCES WILL BECOME MORE ISOLATED. SEVERE
WEATHER IS NOT ANTICIPATED WITH THE WEAK FLOW ALOFT LIMITING UPDRAFT
ORGANIZATION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1110 AM MDT SUN JUL 7 2013
VFR CONDITIONS AND WINDS GENERALLY LESS THAN 12KT SHOULD PERSIST AT
BOTH KGLD AND KMCK TERMINALS THROUGH THE TAF PERIOD. WIND
DIRECTION WILL GENERALLY KEEP AN EASTERLY COMPONENT THROUGH THE
TAF PERIOD...THOUGH IT WILL BE SOMEWHAT ERRATIC DUE TO
THUNDERSTORM ACTIVITY AND FRONTAL POSITIONS. A STALLED FRONT ALONG
THE KS/CO BORDER WILL ACT AS A FOCUS FOR SCATTERED THUNDERSTORM
DEVELOPMENT THIS AFTERNOON/EVENING...WITH ACTIVITY POSSIBLY
LINGERING AT KMCK LATER THAN KGLD AS A DISTURBANCE PASSES TO THE
NORTH AND EAST. THERE IS SOME INDICATION BY MODELS OF MVFR VIS BY
SUNRISE MON WITH LIGHT FOG DEVELOPING AS A RESULT OF MOIST
EASTERLY FLOW NORTH OF THIS FRONT. WITH LLJ INCREASING BOUNDARY
LAYER MIXING OVER KGLD/KMCK AND FRONT BEGINNING TO SHIFT TO THE
NORTH AND WEST I AM NOT CONFIDENT ENOUGH TO ADD THIS TO TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DJR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1255 PM MDT SUN JUL 7 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1254 PM MDT SUN JUL 7 2013
LATEST WV IMAGERY AND RAP ANALYSIS SHOW H5 RIDGE STILL IN PLACE
ACROSS SOUTHERN PLAINS WITH SERIES OF WEAK SHORTWAVE TROUGHS
ROTATING AROUND WESTERN AND NORTHERN EXTENT OF RIDGE THROUGH
WESTERLY FLOW. AT THE SURFACE A COLD FRONT HAS STALLED ALONG THE
KS/NE BORDER WITH A SURFACE TROUGH EXTENDING SOUTH ALONG THE KS/CO
BORDER.
A WEAK SHORTWAVE TROUGH EXPECTED TO DROP SOUTH OUT OF WESTERN
NEBRASKA LATE THIS AFTERNOON AND TONIGHT WILL COMBINE WITH THESE
SURFACE FEATURES TO INITIATE SCATTERED THUNDERSTORMS ACROSS THE CWA.
PRIMARY FOCUS SHOULD BE ALONG FRONT WHERE HIGH TD VALUES NORTH OF
THE FRONT HAVE RESULTED IN ML CAPE 1000-1500 J/KG AS OF THE LATEST
RAP ANALYSIS. BETTER DEEP SHEER IS EXPECTED TO BE IN PLACE NORTH OF
THE FRONT WHERE 0-6KM BULK SHEER AROUND 35KT BY 00Z COULD SUPPORT A
SEVERE WIND AND HAIL THREAT. THERE IS LESS INSTABILITY AND MORE CIN
TO OVERCOME FURTHER SOUTH ALONG THE SURFACE TROUGH...HOWEVER AS
DAYTIME HEATING CONTINUES AND THE SHORTWAVE TROUGH MOVES SOUTH WE
SHOULD BE ABLE TO SEE AT LEAST ISOLATED THUNDERSTORMS DEVELOPING
ALONG THE SURFACE TROUGH THIS AFTERNOON/EVENING. PWAT VALUES
1.2-1.3" REPRESENT AN ANOMALOUSLY WET ATMOSPHERE FOR THIS TIME OF
YEAR...AND AS WAS THE CASE YESTERDAY MANY OF THESE STORMS WILL BE
SLOW MOVERS...SO HEAVY RAIN WILL BE A CONCERN WHERE STORMS DEVELOP.
LEE TROUGH IS EXPECTED TO BEGIN TO DEEPEN LATE TONIGHT WITH LLJ
BUILDING ACROSS THE NE HALF OF THE CWA. WITH INCREASING ISENTROPIC
ASCENT AND H85 SUPPORT WE COULD SEE LINGERING THUNDERSTORMS IN
PROXIMITY OF THE FRONTAL ZONE ACROSS OUR NE CWA...SO I KEPT ISO
THUNDER MENTION MOST OF THE NIGHT FOR THOSE LOCATIONS. THERE IS
SOME INDICATION WITH VERY MOIST E-NE BL FLOW OF FOG DEVELOPING IN
SW NEBRASKA...HOWEVER WITH BL LIKELY MIXED WITH LLJ INCREASING AND
FRONT POSSIBLY SHIFTING NORTH I WASNT CONFIDENT ENOUGH TO ADD
MENTION.
DESPITE LARGE SCALE FORCING IN PLACE MONDAY IT DOES LOOK LIKE A
TROUGH AXIS/DRYLINE ALONG KS/CO BORDER COULD HELP INITIATE
THUNDERSTORMS BY THE AFTERNOON WITH INSTABILITY BUILDING ACROSS THE
EASTERN CWA. I WASNT CONFIDENT ENOUGH TO ADD MORE THAN SLIGHT CHANCE
MENTION AT THIS POINT. H85 TEMPS ARE ACTUALLY ADVERTISED TO BE 2-3C
WARMER THAN THE LAST FEW DAYS WHEN HIGHS HAVE BEEN AROUND 100F...SO
WE COULD BE LOOKING AT NEAR RECORD HIGH TEMPS ACROSS THE CWA MONDAY
WITH VALUES IN THE 100S ACROSS THE AREA.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 227 AM MDT SUN JUL 7 2013
LONG RANGE MODEL FORECAST INDICATES RIDGE PATTERN INCREASING IN
AMPLITUDE OVER THE FOUR CORNERS REGION FOR WEDNESDAY AND CONTINUING
TO BE PRESENT THROUGHOUT THE ENTIRE EXTENDED PERIOD. 500 MB HEIGHTS
WILL CONTINUE TO INCREASE IN MAGNITUDE INTO NEXT
WEEKEND...INDICATING THE INCREASING STRENGTH OF THE UPPER LEVEL
HIGH. THE UPPER LEVEL JET STREAM LOOKS TO STAY WELL TO THE NORTH
THROUGHOUT THE ENTIRE PERIOD. A SURFACE LOW PRESSURE SYSTEM WILL
STAY IN PLACE OVER THE TRI STATE AREA THROUGHOUT THE PERIOD WITH
STRONG WARM AIR ADVECTION MOVING INTO THE HIGH PLAINS. TEMPERATURES
LOOK TO BE IN THE MID 90S FOR WEDNESDAY AND THURSDAY...INCREASING TO
THE UPPER 90S TO LOW 100S ACROSS THE REGION FOR THE WEEKEND. BEST
CHANCE FOR PRECIPITATION WILL BE WEDNESDAY EVENING AND OVERNIGHT AS
STRONG SURFACE CONVERGENCE WILL HELP WITH THUNDERSTORM ACTIVITY.
ISOLATED CHANCES FOR THUNDERSTORM ACTIVITY WILL BE PRESENT MOSTLY
FOR THE EASTERN COUNTIES IN THE CWA FOR THURSDAY AND INTO NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1110 AM MDT SUN JUL 7 2013
VFR CONDITIONS AND WINDS GENERALLY LESS THAN 12KT SHOULD PERSIST AT
BOTH KGLD AND KMCK TERMINALS THROUGH THE TAF PERIOD. WIND
DIRECTION WILL GENERALLY KEEP AN EASTERLY COMPONENT THROUGH THE
TAF PERIOD...THOUGH IT WILL BE SOMEWHAT ERRATIC DUE TO
THUNDERSTORM ACTIVITY AND FRONTAL POSITIONS. A STALLED FRONT ALONG
THE KS/CO BORDER WILL ACT AS A FOCUS FOR SCATTERED THUNDERSTORM
DEVELOPMENT THIS AFTERNOON/EVENING...WITH ACTIVITY POSSIBLY
LINGERING AT KMCK LATER THAN KGLD AS A DISTURBANCE PASSES TO THE
NORTH AND EAST. THERE IS SOME INDICATION BY MODELS OF MVFR VIS BY
SUNRISE MON WITH LIGHT FOG DEVELOPING AS A RESULT OF MOIST
EASTERLY FLOW NORTH OF THIS FRONT. WITH LLJ INCREASING BOUNDARY
LAYER MIXING OVER KGLD/KMCK AND FRONT BEGINNING TO SHIFT TO THE
NORTH AND WEST I AM NOT CONFIDENT ENOUGH TO ADD THIS TO TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...DR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
131 PM EDT SUN JUL 7 2013
.SYNOPSIS...
HIGH PRESSURE REMAINS ANCHORED OFF THE CAROLINA COAST TODAY...BEFORE
DRIFTING SOUTHEAST MONDAY AS LOW PRESSURE LIFTS THROUGH THE
NORTHEAST STATES. THE ASSOCIATED FRONTAL BOUNDARY DROPS THROUGH THE
MID ATLANTIC MONDAY AND DISSIPATES OVER THE CAROLINAS TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST IR/WV SAT IMAGERY SHOWING AN UPPER LOW OVER IN/IL AT 15Z THIS
MORNING. A MOIST FRONTAL PLUME WAS NOTED FLOWING NORTHWARD AHEAD
OF THE LOW FROM THE EASTERN GULF COAST TO THE EASTERN GREAT LAKES.
MEANWHILE...SUBTROPICAL HIGH PRESSURE (SFC AND ALOFT) REMAINS
ANCHORED OFF THE CAROLINA COAST.
NO MAJOR CHANGES NECESSARY TO THE GOING FORECAST ATTM. THE UPPER
SYSTEM IS WILL CONTINUE TO SLOWLY LIFT TOWARD THE EASTERN GREAT
LAKES TODAY...WITH THE FRONTAL BAND SLOWLY MOVING EASTWARD OVER
THE APPALACHIANS. THERE IS A LACK OF SYNOPTIC SCALE FORCING TODAY
TO TRIGGER CONVECTION LOCALLY DESPITE A RATHER UNSTABLE
ENVIRONMENT. HRRR CONTINUES TO PICK UP ON THIS TREND WELL,
YIELDING ONLY AN ISOLATED TSRA OR TWO AT MOST THROUGH 22Z/6PM.
ACCORDINGLY...HAVE PUSHED BACK POPS WITH SLOWER ONSET THROUGH THIS
TIME FRAME, ORIENTING ISO T WORDING ALONG AND WEST OF HIGHWAY 15
IN THE FAR NW PIEDMONT COUNTIES.
THERE IS VERY LITTLE CHANGE IN THE LOW-LEVEL THERMAL PROFILE, AND
THUS HV STUCK CLOSE TO A PERSISTENCE FORECAST FOR TODAY`S MAXIMA.
LOOK FOR HIGHS RISING INTO THE UPPER 80S IMMEDIATE COAST...TO LOW
90S INLAND. DEWPOINTS SHOULD MIX DOWN INTO THE UPPER 60S DURING
PEAK HEATING...HENCE RESULTANT HEAT INDICES SHOULD ONLY BE A FEW
DEGREES HIGHER THAN THE AMBIENT TEMPERATURE. SKY COVER
CHARACTERIZED AS PARTLY SUNNY WEST TO MOSTLY SUNNY EAST FOR THE
BALANCE OF THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
THE UPPER LOW LIFTS ACROSS THE NORTHEAST AND DAMPENS TONIGHT AND
MONDAY...WITH THE FRONTAL BAND DROPPING INTO THE MID ATLANTIC.
LATEST NUMERICAL GUIDANCE BRINGS THE MOISTURE PLUME INTO THE REGION
MONDAY MORNING AND SLOWLY DROPS IT SE INTO SE VA AND NE NC BY THE
AFTERNOON. THE EARLIER TIMING (EARLIER ARRIVAL OF MID-CLOUDS) ALONG
WITH MOIST ADIABATIC MID-LEVEL LAPSE RATES HAMPERS POTENTIAL
INSTABILITY...WHICH WOULD LIMIT CONVECTIVE COVERAGE MONDAY AFTERNOON.
ADDITIONALLY...THE MID/UPPER LEVEL FLOW BECOMES MORE ZONAL...WHICH
WOULD FURTHER LIMIT COVERAGE. GIVEN THIS...HAVE LOWERED POPS TO
LOW-END CHANCE.
0-6KM BULK SHEAR VALUES ARE STILL PROGGED TO REACH 25-30KT...SO
THERE IS A POSSIBILITY OF ISOLATED STRONGER THUNDERSTORMS IF A FEW
POCKETS OF HIGHER INSTABILITY DO DEVELOP. THE MAIN THREAT WOULD BE
BRIEF HEAVY RAIN AND STRONG WIND GUSTS.
THE BOUNDARY WASHES OUT TUESDAY AS ZONAL PREVAILS ACROSS THE REGION.
GFS/NAM EACH INDICATE AROUND 1500-1800 J/KG OF MLCAPE TUESDAY
AFTERNOON. HOWEVER...DEEP LAYER SHEAR WILL BE MUCH LESS ALONG WITH
LITTLE SYNOPTIC SCALE FORCING. THE HIGHER TERRAIN TO THE WEST WILL
LIKELY BE THE TRIGGER FOR ANY THUNDERSTORMS...SOME OF WHICH COULD
DRIFT EAST INTO THE PIEDMONT...SO CHANCE POPS WILL BE MAINTAINED
THERE WITH SLIGHT CHANCE FARTHER EAST.
SEASONABLY HOT (ALTHOUGH NOT EXCESSIVE) AND HUMID CONDITIONS WILL
CONTINUE MONDAY AND TUESDAY. HIGHS SHOULD RANGE FROM THE UPPER 80S
TO LOW 90S...ALONG WITH LOWS IN THE LOW/MID 70S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
LONG TERM PERIOD STARTS OFF TUE NGT INTO WED WITH ZONAL FLOW ALOFT
OVER THE MID ATLANTIC AND AN UPR-LVL LO STARTING TO DIG OVER THE
GREAT LAKES REGION. ALTHO BEST FORCING AND MOISTURE WILL STAY NW OF
THE LOCAL AREA WED...DID INCLUDE A 20-30% CHC FOR SHRAS/TSTMS DUE TO
DIURNALLY-DRIVEN CONVECTION IN THE WARM SECTOR. BETTER CHC FOR RAIN
(40-50%) COMES LATE THU AS THE UPR-LVL TROF AND ASSOCIATED COLD FRONT
APPROACH FROM THE OH VALLEY AND DEEP-LAYER MOISTURE INCREASES. THE
FRONT WILL SLOW DOWN/STALL OVER THE AREA FRI (AND ALSO SAT?) LEADING
TO CONTINUED CHCS FOR SHRAS/TSTMS.
SLY FLOW AND ABUNDANT LO-LVL MOISTURE WILL CONTINUE TO PRODUCE HUMID
CONDS (DEWPTS AVG IN THE LWR 70S) WITH HI TEMPS IN THE UPR 80S/LWR
90S AND LO TEMPS AVG IN THE LWR 70S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SOME CU AROUND THIS AFTERNOON WITH VFR CIGS NOW AT ALL TAF SITES.
LOOKING AT THE MODEL SOUNDINGS THE CU WILL DISSIPATE AFTER SUNSET
WITH MAINLY SOME CI LEFT. HOWEVER OUT TOWARD RIC COULD HAVE MORE
CLOUDS AS AN UPPER SYSTEM STARTS MOVING TO THE NW OF RIC. THIS
COULD EVEN BRING A SHOWER INTO RIC AFTER MIDNIGHT. KEEPING VFR
CONDITIONS TONIGHT AS BELIEVE ENOUGH WINDS WILL OCCUR TO KEEP
MIXING UP. THE UPPER TROF PUSHES ACROSS TO THE N OF THE AREA ON
MON. THIS COULD PRODUCE SCATTERED SHOWERS OR TSTMS DURING THE DAY
ON MONDAY. MODELS INDICATE THE BEST CHANCES OVER SE VA TO NE NORTH
CAROLINA BY AFTERNOON. OUTSIDE OF THE SHOWERS AND THUNDERSTORMS
VFR CONDITIONS WILL PREVAIL ON MONDAY.
OUTLOOK...SCATTERED TSTMS...MAINLY AFTN/EVE WILL BE POSSIBLE TUE
AND WED. MORE WIDESPREAD PCPN IS POSSIBLE LATE IN THE WEEK.
&&
.MARINE...
GENERALLY BENIGN SUB-SCA CONDITIONS OVER THE MARINE AREA THRU AT
LEAST THE MIDDLE OF THE COMING WEEK. BERMUDA HIGH PRESSURE WILL
SLOWLY WEAKEN/DRIFT EASTWARD TODAY THRU TONIGHT AS A LOW PRESSURE
SYSTEM APPROACHES FROM THE WEST. NO STRONG SFC FRONT WILL BE
ASSOCIATED WITH THIS SYSTEM. WINDS THRU MIDWEEK WILL AVG 10-15 KT
OUT OF THE S/SW. EXPECT 1-2 FT WAVES OVER THE BAY AND 2-3 FT SEAS
OVER COASTAL WATERS...APPROACHING 4 FT OUT 20 NM ON MON AND AGAIN
WED.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...AJZ
NEAR TERM...AJZ/MAM
SHORT TERM...AJZ
LONG TERM...MAS
AVIATION...JDM/JAB
MARINE...JDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
139 PM EDT SUN JUL 7 2013
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 314 AM EDT SUN JUL 7 2013
THE WEATHER PATTERN WILL CHANGE LITTLE OVER THE NEXT FEW DAYS. IT
WILL REMAIN WARM AND HUMID WITH HIGHS IN THE MID TO UPPER 80S. WE
WILL ALSO SEE SCATTERED SHOWERS AND STORMS. THE BEST CHANCE OF
PRECIPITATION IN THE SHORT TERM WILL COME LATE TONIGHT INTO MONDAY
MORNING...WITH ANOTHER GOOD CHANCE ON TUESDAY.
THE SHOWERS AND STORMS SHOULD LINGER INTO WEDNESDAY...BUT THEN THE
LATTER HALF OF THE WEEK LOOKS DRY. DAYTIME TEMPERATURES WILL
LARGELY BE IN THE 80 TO 85 DEGREE RANGE FROM MID WEEK INTO NEXT
WEEKEND.
&&
.UPDATE...
ISSUED AT 1048 AM EDT SUN JUL 7 2013
I UPDATED THE ZONE FORECAST TO INCREASE THE CHANCE FOR SHOWERS
INTO EARLY THIS AFTERNOON OVER THE EASTERN SECTIONS OUR OUR CWA
AND TO DECREASE THE FORECAST HIGH A TOUCH SINCE THERE IS A
CONSIDERABLE AMOUNT OF MID CLOUD AROUND.
THE 700 MB LOW IS NEARLY OVERHEAD OF GRAND RAPIDS AT 9 AM BASED ON
RADAR DATA SHOWING THE SHOWERS PINWHEELING AROUND GRAND RAPIDS.
THIS IS ALSO SUPPORTED BY BOTH VISIBLE SATELLITE LOOPS AND RAP
MODEL 12Z FORECAST. THAT SUPPORTS THE SHOWERS OVER THE INFLOW
SECTION OF THE LOW...EAST OF GRR ACTUALLY WITH A DEFORMATION ZONE
FEATURE FROM NORTHERN KENT COUNTY INTO GRATIOT COUNTY. NOT MUCH
THUNDER HAPPENING THOUGH. WHILE THAT WAS HAPPENING THERE IS AN MCS
OVER THE WESTERN UPPER PENINSULA OF MICHIGAN THAT SEEMS TO BE
WEAKENING AND BUILDING TOWARD THE SOUTHEAST.
WITH THE 700 MB LOW WEAKENING AND MOVING INTO EASTERN LOWER
MICHIGAN THIS AFTERNOON THAT WOULD PUT WESTERN LOWER MICHIGAN IN
NORTHWEST SUBSIDING FLOW ON THE WEST SIDE OF THE LOW. NOT A GOOD
THING IF ONE WANTS SHOWERS. SO MY SPIN IS THE CLOUDS AND SHOWERS
WILL GRADUALLY MOVE EAST OF SOUTHWEST LOWER MICHIGAN DURING THE
AFTERNOON. WITH THE SUBSIDENCE ON THE WEST SIDE OF THE SYSTEM I DO
NOT SEE MUCH THREAT FOR CONVECTION TO DEVELOP SO I HAVE VERY LOW
POPS WEST OF US-131 AFTER 1 PM (WEST WINDS OFF LAKE MICHIGAN DO
NOT HELP THE CAUSE FOR CONVECTION MUCH EITHER).THIS IS STRONGLY
SUPPORTED BY RAP MODEL SOUNDING WITH SHOW A VERY DRY LOOKING
SOUNDING FROM THE SURFACE THROUGH 300 MB BY 21Z NEAR GRR.
IT IS MORE MOIST ON THE RAP SOUNDING IN THE LAN/JXN AREA THIS
AFTERNOON WITH NEAR 1800 J/KG OF CAPE BUT I WITH GENERIC WEST WINDS
THROUGH 700 MB BY 21Z I SEE LITTLE REASON FOR MUCH SURFACE
CONVERGENCE SO I AM STILL NOT TO EXITED ABOUT STORM POTENTIAL EVEN THERE.
WE WILL HAVE TO WATCH WHAT HAPPENS WITH THE MCS OVER THE WESTERN
UPPER PENINSULA FOR THIS EVENING BUT EVEN THERE... THE LOW LEVEL
JET IS LARGELY IN WISCONSIN THIS EVENING AND THE BEST JET DYNAMICS
ARE OVER NORTHERN WI AND THE MICHIGAN UP SO I BELIEVE LITTLE WILL
HAPPEN OVER WESTERN LOWER MICHIGAN TONIGHT EITHER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 314 AM EDT SUN JUL 7 2013
WIDELY SCATTERED SHOWERS AND STORMS WILL CONTINUE THROUGH THE SHORT
TERM. HOWEVER THE PRECIPITATION SHOULD BECOME MORE WIDESPREAD LATE
TONIGHT INTO MONDAY MORNING...AND THEN AGAIN ON TUESDAY. IT WILL
REMAIN WARM AND HUMID THROUGH TUESDAY.
AN UPPER LOW WAS OVER SE IL THIS MORNING AND IT WAS DRIFTING NE.
THIS WILL BRING THE CENTER OF THE LOW TO NE INDIANA BY THIS
AFTERNOON. THIS IS FURTHER NORTH THAN WHAT PREVIOUS MODELS HAVE
BEEN SHOWING. FOR THE PAST FEW DAYS THERE HAS BEEN DAYTIME
THUNDERSTORMS NEAR AND AROUND THIS LOW. HOWEVER THE COVERAGE OF THE
PCPN STILL WARRANTS 30/40 POPS. ALSO BY THE END OF THE DAY A COLD
FRONT WILL BE MOVING ACROSS WI. THIS COULD BRING ISOLATED PCPN INTO
THE NW CWA AND 20/30 POPS WILL BE CARRIED OVER THE NW CWA.
DECENT SET UP FOR AN MCS TO ROLL ALONG THE FRONT TO OUR WEST TONIGHT
WITH THE ASSISTANCE OF A LOW LEVEL JET. SEEMS LIKE THIS MAY TRACK
NEAR THE MI/IN BORDER LATE TONIGHT IN A WEAKENING STATE. ITS
DOUBTFUL THAT SEVERE WILL OCCUR AS THIS COMPLEX WILL BE RUNNING AWAY
FROM THE BEST INSTABILITY AND JET SUPPORT BY THE TIME IT REACHES
US...BUT WILL CARRY 40/50 POPS SOUTH OF I-96.
EXPECT SOMEWHAT LESS CONVECTION INTO MONDAY AFTERNOON AND MONDAY
NIGHT. THE FRONT EASES INTO THE REGION...BUT IT WASHES OUT OVER THE
NORTHERN OR CENTRAL CWA. THIS MAY SUPPORT SOME WIDELY SCATTERED
STORMS BUT WITHOUT A FOCUSED JET THESE SHOULD NOT BE SEVERE.
ANOTHER UP TICK IN THE STORM ACTIVITY IS EXPECTED INTO TUESDAY.
ANOTHER COLD FRONT WILL BE CROSSING WI WITH A STRONG LOW LEVEL JET
ALONG IT. THE CONVERGENCE FROM THIS JET SHOULD REACH US BY LATE
AFTERNOON WHEN THE CHANCE OF ORGANIZED/SEVERE STORMS WILL BE
POSSIBLE. HAVE INCREASED POPS TO LIKELY SOUTH OF I-96 AS THIS IS
WHERE THE LLJ IS PROGGED TO BE NOSING INTO.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 AM EDT SUN JUL 7 2013
BEST CHANCE OF RAIN IN THE EXTENDED WILL BE TUESDAY NIGHT INTO
EARLY WEDNESDAY AS UPPER TROUGH AXIS AND SFC LOW MOVES THROUGH.
PLENTY OF MOISTURE AVAILABLE AND MCS DEVELOPMENT IS POSSIBLE TUESDAY
NIGHT INTO WEDNESDAY MORNING WITH HEAVY RAIN THREAT. MODELS HAVE
TRENDED TO A LESS AMPLIFIED TROUGH AND WEAKER SHEAR PROFILES SO
SEVERE THREAT NOW SEEMS TO BE DIMINISHED.
KEPT THE LATTER PART OF THE WEEK DRY AS SFC HIGH IS IN PLACE AND DRY
SOUNDINGS RULE FROM LATE WEDNESDAY THROUGH THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 138 PM EDT SUN JUL 7 2013
CONDITIONS SHOULD BE VFR FOR THE MAJORITY OF THE TIME THROUGH 18Z
MON...WITH SOME MVFR POSSIBLE IN FOG TONIGHT AND ISOLATED SHOWERS.
LOWER CLOUD COVER IN PLACE EARLIER THIS MORNING HAS BROKEN
UP/LIFTED INTO A VFR DECK THIS AFTERNOON. SOME SCATTERED CLOUDS
AROUND 2000-3000 FT STILL COULD BRIEFLY GO MVFR...BUT CONDITIONS
WILL GENERALLY IMPROVE THROUGH THE AFTERNOON. THERE COULD BE A
SHOWER ACROSS THE ERN TERMINALS OF KLAN AND KJXN DUE TO THE UPPER
LOW CLOSER BY...SO VCSH WAS PUT IN THE FCST THERE UNTIL ABOUT 23Z.
WE CAN NOT RULE OUT A FEW SHOWERS APPROACHING FROM THE W/NW LATE
TODAY FROM CONVECTION THAT MIGHT DEVELOP ACROSS WISCONSIN THIS
AFTERNOON. CONFIDENCE IS TOO LOW AT THIS TIME TO PUT ANYTHING IN
THE FCST FOR THIS.
WINDS WILL DIMINISH A BIT AROUND SUNSET AND REMAIN AROUND 3-5
KNOTS OVERNIGHT. THE MOIST/HUMID AIR MASS WILL ALLOW FOR SOME
LIGHT FOG TO BE POSSIBLE ONCE AGAIN TOWARD DAYBREAK MON.
A WEAK WAVE WILL MOVE INTO THE AREA DURING THE DAY ON MON THIS
WILL PRODUCE ANOTHER THREAT OF A FEW SHOWERS. WE HAVE THESE IN THE
FCST BEGINNING AROUND 14Z AND LASTING THROUGH 18Z.
&&
.MARINE...
ISSUED AT 314 AM EDT SUN JUL 7 2013
SOUTHERLY WINDS ARE EXPECTED TO INCREASE TONIGHT AHEAD OF AN
APPROACHING COLD FRONT. AREAS NORTH OF HOLLAND WILL SEE WAVES
INCREASE TO 2-3 FEET. THIS IS BELOW SMALL CRAFT CRITERIA...BUT THE
LAKE WILL STILL BECOME RATHER ROUGH. WINDS AND WAVES ARE EXPECTED
TO RELAX INTO MONDAY AS THE FRONT MOVES IN.
&&
.HYDROLOGY...
ISSUED AT 314 AM EDT SUN JUL 7 2013
THE WIDELY SCATTERED SHOWERS SHOULD RESULT WITH MOST RIVER BASIN
SEEING AN AVERAGE OF AROUND A QUARTER INCH OF RAIN THROUGH MONDAY
NIGHT...PERHAPS A BIT HIGHER SOUTH OF I-96.
A BETTER CHANCE FOR WIDESPREAD RAINS COMES IN ON TUESDAY. EXPECT
AREAS INLAND FROM THE LAKE AND SOUTH OF HIGHWAY 20 WILL STAND THE
BEST CHANCE OF SEEING A HALF INCH OR MORE OF RAIN. LOCALIZED
HEAVIER RAINS MAY OCCUR AND PRODUCE NUISANCE FLOODING...BUT IN
GENERAL NO HYDRO ISSUES ARE EXPECTED.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...OSTUNO
AVIATION...NJJ
HYDROLOGY...JK
MARINE...JK
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
130 PM EDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 1030 AM EDT SUN JUL 7 2013
REMNANTS OF OVERNIGHT MCS CONTINUE TO MOVE IN THE EASTERN U.P. THIS
MORNING AS THEY CONTINUE TO DIMINISH. TRAINING STORMS EARLIER THIS
MORNING DUMPED BETWEEN 2 AND 4 INCHES OF RAIN ACROSS GOGEBIC AND
ONTONAGON COUNTIES BUT AMOUNTS HAVE BEEN MUCH LIGHT FARTHER EAST.
EXPECT A BREAK IN PRECIPITATION INTO THE AFTERNOON HOURS. HIRES
MODELS CONTINUE TO SHOW SCATTERED REDEVELOPMENT OCCURRING ALONG THE
SURFACE TROUGH THIS AFTERNOON AS IT SAGS SOUTHWARD. STILL SOME
UNCERTAINTY THERE AND WILL HAVE TO MONITOR THROUGH THE AFTERNOON
HOURS. WILL ADJUST POP FORECAST ACCORDINGLY WITH THAT THOUGHT
PROCESS IN MIND. WITH MORE CLOUDS TODAY...TEMPS SHOULD ONLY CLIMB
INTO THE UPPER 70S TO AROUND 80.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 505 AM EDT SUN JUL 7 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MAINLY ZONAL PATTERN ACROSS
THE NRN CONUS AND SRN CANADA WITH A CUTOFF MID/UPPER LEVEL LOW TO
THE SOUTH OVER IL/IN. A SHORTWAVE TROUGH COMBINED WITH UPPER LEVEL
DIV WITH THE RIGHT ENTRANCE OF A 75 KNOT 250 JET OVER NRN
ONTARIO...AND FAVORABLE 925-700 THETA/E ADVECTION FROM THE UPPER MS
VALLEY SUPPORTED AN AREA OF SHRA/TSRA OVER LAKE SUPERIOR INTO W
UPPER MI AND NW WI WITH THE STRONGEST CONVECTION ON THE WRN END OF
THE PCPN AREA. AT THE SFC...A COLD FRONT HAD GRADUALLY SAGGED TO THE
SOUTH INTO NRN UPPER MI.
TODAY...EXPECT THAT WEAKENING SHRA/TSRA WILL CONTINUE TO SPREAD
THROUGH WRN INTO N CNTRL UPPER MI EARLY...PER RADAR AND SHORT RANGE
MODEL TRENDS...BEFORE THE FORCING ASSOCIATED WITH THE SHRTWV AND LOW
LEVEL INFLOW WEAKENS. BY LATE MORNING INTO THE EARLY
AFTERNOON...THERE MAY BE A LULL IN ANY PCPN BEFORE ADDITIONAL SCT
SHRA/TSRA ALONG THE FRONTAL BOUNDARY REINFORCED BY LAKE SUPERIOR
BREEZE. THERE MAY BE ENOUGH THINNING OR BREAKS IN THE CLOUD COVER
FOR TEMPS TO RECOVER TO NEAR 80...PUSHING MLCAPE VALUES INTO THE
1000-1500 J/KG RANGE. HOWEVER...0-6KM SHEAR VALUES TO NEAR 30 KT
WILL REMAIN MARGINAL FOR STRONGER OR SEVERE ORGANIZED CONVECTION.
THERE MAY STILL BE BRIEF HEAVY RAIN AND GUSTY WINDS WITH TSRA THAT
DEVELOP.
TONIGHT...AS DAYTIME HEATING SUBSIDES AND THE FRONT CONTINUES TO
PUSH TO THE SOUTH...THE REMAINING PCPN SHOULD SHIFT TO THE SOUTH AND
EAST AND DIMINISH. WITH LINGERING LOW LEVEL MOISTURE AND MID LEVEL
DRYING...AREAS OF FOG ARE EXPECTED TO DEVELOP. THERE COULD ALSO BE
SOME DRIZZLE NEAR THE WRN SHORE AS WEAK LOW LEVEL CONV DEVELOPS WITH
MOIST NE FLOW OFF THE LAKE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 505 AM EDT SUN JUL 7 2013
THE SURFACE FRONT WILL BE SOUTH OF THE FORECAST AREA MONDAY
MORNING...WITH WEAK SURFACE RIDGING ACROSS LAKE SUPERIOR. THIS WILL
HELP TO OVERALL DRY THE ATMOSPHERE...HOWEVER IT WILL ALSO ALLOW FOR
WEAK UPSLOPE FLOW IN AREAS NEAR LAKE SUPERIOR. THE NAM AND EVEN THE
GFS SUGGEST A VERY SHALLOW SATURATED LAYER BELOW 1000 FT WHICH WOULD
IMPLY AT LEAST A CHANCE FOR LOW CLOUDS AND DRIZZLE NEAR LAKE
SUPERIOR MONDAY MORNING. HOWEVER...BY AFTERNOON ANY LOW
CLOUD/DRIZZLE SHOULD MIX OUT. WILL ALSO MAINTAIN THE SLIGHT CHANCE
POPS IN THE LAKE BREEZE AREAS OF WESTERN UPPER MICHIGAN AND NEAR
LAKE MICHIGAN. ALTHOUGH THE NWP SUGGESTS A FAIRLY DRY ATMOSPHERE
BEHIND THE FRONT AND BROAD SCALE SUBSIDENCE...THE 850MB FRONT
WILL STALL OUT OVER THE AREA AND INTERIOR INSTABILITY RISES TO
NEARLY 1500 J/KG. NOT TO CONFIDENT THAT ANY SHOWERS/STORMS WILL
OCCUR MONDAY AFTERNOON...BUT ALSO NOT CONFIDENT ENOUGH TO REMOVE THE
MENTION. REGARDLESS...MONDAY WILL BE COOLER AND A LITTLE LESS HUMID
THAN TODAY WITH READINGS NEAR LAKE SUPERIOR DROPPING BACK INTO THE
LOWER-MID 70S.
MONDAY NIGHT SHOULD BE A FAIRLY QUIET NIGHT ACROSS THE AREA AS THE
NEXT LOW PRESSURE SYSTEM DEVELOPS ACROSS THE PLAINS. THE MODELS HAVE
BACKED OFF ANY PCPN FOR THE AREA MONDAY NIGHT...INSTEAD FOCUSING IT
ACROSS MN WHERE THE BETTER LOW LEVEL MOISTURE TRANSPORT AND DEEP
MOISTURE WILL BE LOCATED.
SOME DISAGREEMENT REMAINS REGARDING TIMING OF PRECIPITATION ON
TUESDAY. THERE IS A HINT FROM THE ECMWF AND GFS THAT AN MCS WILL BE
ONGOING TO WEST OF THE AREA IN THE BROAD WARM ADVECTION/ISENTROPIC
LIFT AREA IN SRN MN. THIS LEADS TO MUCH UNCERTAINTY REGARDING
CONVECTIVE EVOLUTION TUE FOR THE AREA. THE MAIN FORCING MECHANISM
TUE AND TUE NIGHT WILL CONTINUE TO BE THE NRN STREAM ENERGY DIVING
OUT OF CANADA AND AMPLIFYING DURING THE DAY...AND HAVE OPTED TO
FOCUS ON THIS FEATURE SIMILAR TO THE NAM SOLUTION. WITH THE BEST
FORCING WITH ENERGY BEING LATE TUE AFTN AND EVENING...HAVE OPTED TO
MAINTAIN THE HIGHEST POPS DURING THIS PERIOD. DEPENDING ON THE
AMOUNT OF DEBRIS CLOUDS...MODEST INSTABILITY IS POSSIBLE ACROSS THE
AREA TUE AFTN/EVENING HELPING TO MAINTAIN THUNDERSTORM DEVELOPMENT
ALONG THE FRONT. CANNOT TOTALLY RULE OUT SOME ORGANIZATION TO THE
STORMS LATER TUESDAY INTO TUESDAY EVENING AS A COUPLED UPPER JET
STRUCTURE DEVELOPS ACROSS THE NRN LAKES IN RESPONSE TO THE WAVE
BECOMING NEGATIVELY TILTED.
THE FRONT MOVES THROUGH THE AREA BY WEDNESDAY MORNING. MAY BE SOME
RESIDUAL WRAP AROUND MOISTURE ACROSS THE AREA IN THE MORNING...BUT
OTHERWISE THE WEATHER SHOULD IMPROVE DURING THE DAY. MODELS IN
EXCELLENT AGREEMENT IN SHOWING BROAD HIGH PRESSURE ACROSS THE UPPER
GREAT LAKES FOR THE END OF THE WEEK WITH RISING HEIGHTS BY THE
WEEKEND. TEMPERATURES WILL BE SEASONABLE THU AND FRIDAY ALTHOUGH
ABOVE NORMAL TEMPS MAY RETURN BY SATURDAY WITH 850MB TEMPS PROGGED
TO RISE TO +16 ACROSS THE WEST. CANNOT RULE OUT SHOWERS SATURDAY
AFTERNOON AS BOTH THE GFS AND ECMWF HINT AS AN UPPER WAVE MOVING
THROUGH THE AREA IN THE WESTERLY FLOW. HOWEVER...AT THIS TIME WILL
OPT TO MAINTAIN A DRY FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 130 PM EDT SUN JUL 7 2013
SURFACE TROUGH WILL DROP SLOWLY SOUTHWARD ACROSS UPPER MICHIGAN THIS
AFTERNOON SHIFTING WINDS FROM THE SOUTHWEST TO THE NORTH. SCATTERED
SHOWERS AND A FEW THUNDERSTORMS WILL DEVELOP ALONG THIS BOUNDARY AS
IT MOVES SOUTHWARD BUT ANTICIPATED AREAL COVERAGE IS NOT ENOUGH TO
INCLUDE A MENTION AT THE TAF SITES. LOW LEVEL MOISTURE WILL REMAIN
AFTER THE TROUGH PASSES AND WITH SUBSTANTIAL MID LEVEL DRYING EXPECT
FOG AND EVEN SOME DRIZZLE TO DEVELOP AT ALL THREE FORECAST LOCATIONS
LOWERING CONDITIONS TO VLIFR NEAR AIRPORT MINIMUMS FOR THE OVERNIGHT
AND EARLY MONDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 505 AM EDT SUN JUL 7 2013
GIVEN EARLY SHIP OBSERVATIONS OF ZERO VISIBILITY OVER WESTERN LAKE
SUPERIOR AND VERY HUMID AIRMASS OVER CHILLY WATER FOLLOWING SOME
SHOWERS...A DENSE FOG ADVISORY WILL REMAIN IN EFFECT THIS MORNING
FOR THE WEST HALF OF LAKE SUPERIOR. SOME DRYING ON SUNDAY
AFTERNOON FOLLOWING A COLD FRONTAL PASSAGE SHOULD DISSIPATE THE
THICKEST FOG.
WINDS WILL REMAIN BELOW 15 KT ACROSS LAKE SUPERIOR THROUGH TUESDAY
AS A WEAK SURFACE TROUGH DROPS SOUTHWARD ACROSS THE LAKE FOLLOWED BY
AN AREA OF HIGH PRESSURE. WITH SHOWERS AND THUNDERSTORMS EARLY TODAY
AND ADDITIONAL SCT SHRA/TSRA POSSIBLE THIS AFTERNOON...AREAS
OF FOG WILL CONTINUE ACROSS THE LAKE. AS ANOTHER LOW DEVELOPS OVER
THE PLAINS ON TUESDAY AND APPROACHES LAKE SUPERIOR ON
WEDNESDAY....NORTHWESTERLY WINDS OF 15 TO 25 KNOTS WILL BE POSSIBLE
BEHIND FOR A TIME WEDNESDAY AND WEDNESDAY NIGHT. A SURFACE HIGH
MOVING OVER THE UPPER LAKES LATE IN THE WEEK WILL ALLOW LIGHT WINDS
TO RETURN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MZ
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1158 AM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CDT SUN JUL 7 2013
A COUPLE OF WEAK BOUNDARIES OF CONCERN TO START THE DAY. ONE IS A
TROUGH/COLD FRONT THAT AT 3 AM WAS ALONG THE ND/MN DOWN TO A WEAK
LOW OVER NE SODAK...EXTENDING BACK SW INTO CENTRAL NEB. OTHER
BOUNDARY IS A STATIONARY FRONT EXTENDING FROM AROUND MORRIS ACROSS
CENTRAL MN INTO THE HAYWARD AREA. LLJ AND WAA REGIME NORTH OF THE
STATIONARY BOUNDARY HAS GENERATED A CLUSTER OF STORMS OVER LAKE
SUPERIOR THAT HAVE STAYED SAFELY AWAY FROM THE MPX AREA OVERNIGHT.
FOR TODAY...THIS STATIONARY BOUNDARY WILL START TO LOOSE ITS
DEFINITION AS IT SLOWLY SAGS SE. MOST DETERMINISTIC MODELS SAY TODAY
WILL BE DRY AS GRADUAL HEIGHT RISES OVERTAKE THE AREA.
HOWEVER...THE ZONAL FLOW OVER THE REGION TODAY LOOKS TO BE OF THE
DIRTY VARIETY...WITH THE RAP/GFS/NAM SHOWING SMALL PERTURBATIONS
CURRENTLY GENERATING STORMS OUT OVER MT/WY WORKING ACROSS MN DURING
THE LATE AFTERNOON/EARLY EVENING. 07.00 NAM SOUNDINGS SHOW A RATHER
UNSTABLE ENVIRONMENT BEING IN PLACE AS THESE WAVES APPROACH...WITH
2000-3000+ J/KG OF UNCAPPED SBCAPE BEING IN PLACE. AT THE SAME
TIME...RAP SOUNDINGS ONLY ABLE TO GENERATE 1500 J/KG AT BEST.
700-500 MB LAPSE RATES ARE MEAGER ON BOTH /ABOUT 6 DEG C PER
KM/...WITH THE DIFFERENCE COMING WITH HANDLING OF LOW LEVEL
MOISTURE...AS THE RAP LOOKS A LITTLE AGGRESSIVE ON MIXING OUT DEWPS
THIS AFTERNOON...WHICH IN TURN IS IMPACTING ITS INSTABILITY
FORECAST. NAM IDEA IS PROBABLY MORE REALISTIC...BUT GIVEN MID-LEVEL
LAPSE RATES...WOULD FAVOR 1500-2500 J/KG OF CAPE TO WORK WITH TODAY.
WITH ALL THAT SAID...AT THE MOMENT ONLY HAVE CHANCE POPS MENTIONED
IN THE FAR ERN CWA THIS AFTERNOON AS THIS IS WHERE SOME FORM OF LLJ
FORCING LOOKS TO RESIDE...BUT GIVEN THE INSTABILITY MENTIONED
ABOVE...COULD SEE STORMS DEVELOP ANYWHERE ALONG/SOUTH OF THE
STATIONARY BOUNDARY. 03Z HOPWRF ENSEMBLE REFLECTIVITY FORECASTS HINT
AT THIS HAPPENING...WITH SCATTERED CONVECTION SEEN AT 21Z ON MEMBERS
1/3/4 ACROSS MOST OF THE AREA. GUESS AT THIS POINT...THIS "WET
PATTERN" THAT SET IN FRIDAY NIGHT HAS NOT EXACTLY PRODUCED MUCH IN
THE WAY OF OBSERVABLE PRECIPITATION IN THE MPX AREA...SO AM A BIT
GUN SHY ON GOING TO HIGH WITH POPS AT THIS POINT. WITH LOW LEVEL
FLOW BACKING OFF CONSIDERABLY TODAY...LOW LEVEL SHEAR WILL BE PRETTY
WEAK TODAY...BUT WITH INVERTED V SOUNDINGS SEEN IN MODELS...A
CONDITIONAL WIND THREAT WOULD EXIST.
FOR TONIGHT...LLJ FORCING AND THICKNESS PATTERN CONTINUE TO SHOW THE
MPX AREA SPLIT BETWEEN BETTER REGIONS OF FORCING FOR CONVECTION OVER
NRN IL/SRN WI AND OUT WEST ACROSS THE DAKOTAS...SO EXPECT TONIGHT TO
BE DRY ONCE ANY DIURNALLY DRIVEN ACTIVITY DISSIPATES THIS EVENING.
FOR TEMPERATURES...DENSE MID LEVEL CLOUD COVER SHOULD CLEAR ERN
AREAS FAIRLY QUICKLY THIS MORNING...WITH A FAIR AMOUNT OF SUNSHINE
EXPECTED AS A RESULT. AIR-MASS HAS CHANGED VERY LITTLE SINCE
YESTERDAY...SO EXPECT HIGHS TO BE VERY SIMILAR TO WHAT WAS SEEN
OUTSIDE OF CENTRAL MINNESOTA ON SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 409 AM CDT SUN JUL 7 2013
MAIN CHALLENGE IS TRYING TO PINPOINT THE TIMING AND PLACEMENT OF
POPS EARLY IN THE WEEK BEFORE WE DRY OUT WEDNESDAY THROUGH FRIDAY.
THE UPPER LEVEL RIDGE ANCHORED OVER THE DESERT SOUTHWEST WILL
REMAIN THROUGHOUT THE PERIOD. MONDAY SHOULD START OUT DRY AS THE
LOW LEVEL JET AS SEEN IN THE H925 WINDS AND MOISTURE TRANSPORT
WILL REMAIN WELL SOUTH OF THE FORECAST AREA IN SOUTHERN
IOWA/ILLINOIS. THE HUMID AIR-MASS WILL PERSIST ACROSS THE UPPER
MIDWEST...AND WITH LITTLE MIXING EXPECTED ON MONDAY HAVE INCREASED
DEW-POINTS INTO THE LOW 70S. BY MONDAY EVENING FORECAST MODELS
INDICATE A SUBTLE H500 SHORTWAVE ROTATING AROUND THE PERIPHERY OF
THE AFOREMENTIONED MONSOON RIDGE AND THIS SHOULD TRIGGER OFF SOME
DEEP CONVECTION ON THE LEE SIDE OF THE ROCKIES WHICH WILL ADVECT
EASTWARD OVER THE HIGH PLAINS OF THE DAKOTAS...AND COULD REACH THE
CWA LATER MONDAY NIGHT INTO EARLY TUESDAY MORNING. THE 07.12 GFS
AND ECMWF PLACE THE NOSE OF THE LOW LEVEL JET IN A FAVORABLE
LOCATION FOR CONVECTION OVER THE MISSISSIPPI RIVER VALLEY.
CURRENTLY HAVE THE HIGHEST POPS ALONG I90 NEAR THE IA BORDER...BUT
THESE MAY NEED TO BE ADJUSTED NORTHWARD IF THE MODELS FOLLOW THE
LEAD OF THE ECMWF...WHICH TAKES THE MCS ALONG AND NORTH OF I94.
THERE WILL BE PLENTY OF INSTABILITY AS SREF PLUMES KEEP AROUND
1000 J/KG OF MUCAPE ACROSS THE REGION MONDAY NIGHT...WITH ROUGHLY
30KTS OF DEEP LAYER SHEAR DEPENDING ON THE PLACEMENT OF THE LLJ.
THE FORECAST FOR TUESDAY BECOMES DIFFICULT SINCE MANY OF THE DETAILS
HINGES DIRECTLY ON THE MESOSCALE FEATURES LEFT IN THE WAKE OF THE
EARLY MORNING CONVECTION. A MORE WELL-DEFINED SHORTWAVE CURRENTLY
OFF THE MOVING DOWN THE COAST OF BRITISH COLUMBIA WILL TRANSLATE
EASTWARD IN THE ZONAL FLOW ALONG THE INTERNATIONAL BORDER AND ARRIVE
ACROSS THE UPPER MIDWEST TUESDAY AFTERNOON. THIS WILL DRIVE A COLD
FRONT THROUGH THE REGION ON TUESDAY...HOWEVER EXPECT ANY REMNANT
DEBRIS CLOUDS TO CLEAR OFF ALLOWING THE BOUNDARY LAYER TO RECOVER
DURING THE LATE MORNING HOURS...WITH AN UNSTABLE ENVIRONMENT SETTING
UP ACROSS THE MN/WI BORDER BY TUESDAY AFTERNOON. AN H500 SPEED MAX
OF 60KTS...ALONG WITH 3M/HR HEIGHT FALLS WILL PROVIDE SYNOPTIC SCALE
FORCING FOR SEVERE THUNDERSTORMS AHEAD OF THE COLD FRONT. AS ALLUDED
TO IN THE SPC DAY3 OUTLOOK...ANY OUTFLOW BOUNDARY PRODUCED BY THE
EARLY MORNING CONVECTION WILL BE THE FOCUS FOR AN ENHANCED THREAT OF
SEVERE WEATHER...INCLUDING TORNADOES AS THE SURFACE WINDS BACK AHEAD
OF THE COLD FRONT. NAM BUFR SOUNDINGS FOR TUESDAY AFTERNOON AT KRWF
SHOW A CYCLONICALLY CURVED HODOGRAPH WITH 0-3KM HELICITY OF OVER
300M2/S2. THE GFS IS FASTER WITH THE COLD FRONT...SO ITS LINEAR
SHEAR PROFILE WITH NORTHWEST WIND IS LESS FAVORABLE FOR
TORNADOES...BUT RATHER WOULD SUPPORT STRAIGHT LINE WINDS.
REGARDLESS...TUESDAY SEVERE THREAT LOOKS TO BE THE MAIN CONCERN
DURING THE EXTENDED.
NORTHWEST FLOW IN THE WAKE OF THIS COLD FRONT WILL USHER IN DRIER
AIR AS A CANADIAN HIGH PRESSURE BUILDS ON WEDNESDAY AND KEEPS THE
REGION DRY THROUGH FRIDAY. HAVE INCREASED WINDS SLIGHTLY ABOVE
GUIDANCE ON WEDNESDAY AS FORECAST SOUNDINGS SHOW ANOTHER GOOD MIXING
DAY. LOOKING AHEAD...THE REPRIEVE FROM THE HEAT AND HUMIDITY WILL BE
SHORT-LIVED AS THE THERMAL RIDGE DEVELOPS BY THE END OF THE WORK WEEK
ACROSS THE HIGH PLAINS. WILL ACTUALLY SEE A WEST/EAST TEMPERATURE
GRADIENT BY THE WEEKEND...WITH MUCH WARMER TEMPERATURES ACROSS
WESTERN MINNESOTA. CURRENTLY HAVE MORE OF A BLENDED APPROACH WHICH
YIELDS ONLY MID 80S ACROSS THE WEST. THERE IS STILL
UNCERTAINTY...BUT IF THE H850 TEMPS REMAIN 20-22C WILL LIKELY SEE
HIGHS IN THE MID 90S NEAR THE MN/SD BORDER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1140 AM CDT SUN JUL 7 2013
AS TYPICAL IN THE SUMMER...CONVECTION BEGINS TO DECREASE BY THE
LATE MORNING AS LCL/S LIFT AND THE CAP STRENGTHENS. HOWEVER...IF
ANY THUNDERSTORM COMPLEX CONTINUES THRU THE MID/LATE MORNING HRS
AS IS THE COMPLEX IN NORTHERN SD...THE CHC/S OF IT CONTINUING THRU
THE AFTN IS HIGH. THE ONLY PROBLEM IS A SFC BOUNDARY HAS MOVED
INTO WESTERN MN TODAY. BUT...AT THE SAME TIME SFC MOISTURE HAS
POOLED WHICH HAS ALLOWED FOR MLCAPES TO INCREASE. OVER THE PAST
FEW HRS...THIS SFC BOUNDARY HAS NEARLY STALLED. THIS FRONT AND THE
LEFTOVER CONVECTION ACROSS WC WI WILL LIKELY BE THE FOCUS FOR MORE
SHRA/TSRA DEVELOPMENT THIS AFTN. THE ONLY PROBLEM NEAR MSP AND
SOUTHWARD TO THE MN/IA BORDER...IS THE INCREASING CIN NOTED. THIS
MAY HINDER ANY DEVELOPMENT IN THIS AREA...BUT WITH THE COMPLEX
ACROSS SD MOVING EASTWARD THIS AFTN...IT WILL LIKELY MODIFIED THE
ATMOSPHERE AND CAUSE MORE SHRA/TSRA THAN CURRENT MODELS INDICATE.
BECAUSE OF THIS SCENARIO...WILL ADD VCSH TO ALL BUT AXN WHICH IS
DEEPER IN THE N/NE FLOW AND K-INDEX VALUES ARE VERY LOW ATTM. RWF
WILL LIKELY SEE VCSH BY 20-22Z...BUT TSRA CHC/S ARE TOO VARIABLE
SO NOT ADDING VCTS ATTM. MSP/STC/RNH/EAU ALL HAVE LOW CHC/S OF
SEEING CONVECTION THIS AFTN. HOW WIDESPREAD THE ACTIVITY
GETS...REMAINS UNCERTAIN. WINDS WILL BE GENERALLY LIGHT AND
VARIABLE WITH A MORE N/NE DIRECTION AT STC/AXN...AND MORE S/SW AT
RNH/EAU/MSP/RWF. FOG/BR POTENTIAL IS ALSO GOOD OVERNIGHT WITH THE
BOUNDARY NEAR THE AREA...AND LITTLE BOUNDARY LAYER MIXING.
KMSP...
THE FORECAST IS HIGHLY DEPENDENT ON HOW MUCH MIXING IN THE LOW
LEVELS DEVELOP THIS AFTN AND WHETHER ENOUGH CIN TO LOWER CHC/S OF
SHRA/TSRA. BASED ON THE LATEST REGIONAL RADAR/SFC BOUNDARY OUT
WEST...AND THE CONTINUED TREND OF HIGH K-INDEX/S...WILL CONTINUE
WITH VCSH...WITH THE BEST POTENTIAL OF SHRA/TSRA BETWEEN 23-02Z.
AFT 2Z...THE PROBABILITY IS LOWER FOR SHRA/TSRA CHC/S...BUT WILL
NEED TO WATCH WHAT HAPPENS WITH THE COMPLEX IN SD LATER THIS AFTN.
WINDS WILL BE GENERALLY LIGHT SW THIS AFTN...LIGHT AND VARIABLE
TONIGHT...WITH A LIGHT NE WIND MONDAY.
/OUTLOOK FOR KMSP/
MONDAY NIGHT. CHC TSRA LATE NIGHT. WINDS E 5 KTS.
TUE...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE BCMG NW AT 5 KTS.
WED...VFR. WINDS NW 10G20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS BILLINGS MT
407 PM MDT SUN JUL 7 2013
.SHORT TERM...VALID FOR MON AND TUE...
MAIN FORECAST ISSUE IS SEVERE WX POTENTIAL THIS AFTERNOON/EVENING
AND AGAIN TOMORROW.
WATER VAPOR IMAGERY SHOWS WSW FLOW ALOFT WITH SHORTWAVE ENERGY
APPROACHING FROM THE GREAT BASIN. A STRONGER TROF CAN BE SEEN
ALONG THE PAC NW COAST...AND THIS FEATURE WILL BE A PLAYER FOR US
MONDAY AND MONDAY NIGHT. PWATS IN PLACE ARE QUITE HIGH AND IN THE
VICINITY OF AN INCH...PERHAPS A BIT HIGHER IN OUR EAST. LOW LEVEL
E-SE WINDS ARE INCREASING...PROVIDING GREATER SHEAR AND LOW LEVEL
MOISTURE THAN WE SAW ON SATURDAY...AND LATEST 850MB ANALYSIS
SUGGESTS NOSE OF 850MB DEWPTS TO +13C IN FAR SE MT. WE REMAIN
UNDER RRQ OF 60KT H3 JET TO OUR NORTH...THUS MODEST SYNOPTIC
ASCENT IS PRESENT. OVERALL INGREDIENTS ARE IN PLACE FOR SEVERE
WEATHER LATE THIS AFTN AND EVENING. RECENT HRRR RUNS AGREE WITH
THIS ASSESSMENT AND HAVE BEEN CONSISTENT.
CONVECTION BEGINNING TO INITIATE OVER OUR SW MTNS WITH A FEW
LIGHTNING STRIKES NOTED SOUTH OF LIVINGSTON. A LONE CELL HAS
EMERGED FROM THE CU FIELD SE OF BROADUS. WILL BE INTERESTING TO
SEE WHAT SERN CELL WILL DO OVER THE NEXT COUPLE HOURS...SFC TEMPS
NEAR THE MID 80S MAY BE ENOUGH TO BREAK CAP THAT HAS BEEN IN
PLACE. OTHERWISE FOCUS SHOULD BE IN OUR WEST AS ACTIVITY SPREADS
OFF THE HIGH TERRAIN...SHIFTING EAST OVER TIME.
GREATEST SEVERE POTENTIAL THIS AFTN AND EVENING WILL BE EAST OF
BILLINGS IN REGION OF GREATER INSTABILITY AND SHEAR...ESPECIALLY
AS LOW LEVEL JET KICKS IN THIS EVENING. FOR MONDAY...OUR ENTIRE
AREA WILL BE AT AN ELEVATED RISK FOR SEVERE STORMS DUE TO
COMBINATION OF ASCENT FROM PAC NW TROF AND SURFACE COLD FRONT.
LARGE HAIL AND DAMAGING WINDS MAIN THREATS. HEAVY RAIN WILL
CONTINUE TO BE A POSSIBILITY BOTH TODAY AND TOMORROW DUE TO THE
MOISTURE RICH AIRMASS IN PLACE.
PASSAGE OF TROF...SURGE OF DRIER AIR AND SHIFT TO NW FLOW ALOFT
WILL SIGNAL THE BEGINNINGS OF A PATTERN SHIFT ON TUESDAY...AS THE
MOIST AIRMASS FINALLY GETS CLEANED OUT. COULD BE SOME MORNING
SHOWERS ON TUESDAY ALONG PV MAX...BUT OTHERWISE EXPECT DRIER AND
MORE STABLE CONDITIONS AS COOLER SFC RIDGE BUILDS IN FROM THE NW.
HAVE LOWERED POPS TUESDAY AFTERNOON AND NIGHT.
AS FOR TEMPS...MONDAY WILL BE THE WARMER OF THE NEXT TWO DAYS...
WITH PREFRONTAL CONDITIONS PERHAPS ALLOWING FOR TEMPS NEAR 90F.
TUESDAY WILL BE POSTFRONTAL AND COOLER WITH UPPER 70S TO MID 80S
FOR HIGHS...OR A LITTLE BELOW NORMAL.
JKL
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
MINIMAL CHANGES TO THE EXTENDED PERIOD...DUE IN LARGE PART TO
MODEL INCONSISTENCY FOR LATTER PORTIONS OF THE PERIOD.
THE PERIOD BEGINS WED UNDER AN UPPER LEVEL RIDGE...SO EXPECT HOT
AND MAINLY DRY CONDITIONS. MODELS DO SHOW SOME SHORTWAVE ACTIVITY
ROUNDING THE RIDGE...WITH SE LOW LEVEL FLOW OVER SOUTHEAST MONTANA
LATE WED AFTN/EVE...SO I KEPT A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST ACROSS THE SE. RIDGING DOMINATES
THROUGH MUCH OF THE DAY THURS...SO HOT AND DRY CONDITIONS WILL
AGAIN BE THE RULE. A WEAK COLD FRONT...ALONG WITH SHORTWAVE
ACTIVITY...WILL MOVE ACROSS THE REGION THURS NIGHT...SO WE MAY SEE
SOME CONVECTIVE ACTIVITY THURS EVE/NIGHT OVER THE WESTERN
MOUNTAINS...AND OVER THE EAST...WHERE SHEAR IS BETTER AND THE
ATMOSPHERE IS LESS CAPPED. FRI LOOKS TO BE A TAD COOLER BEHIND THE
FRONT...BUT STILL QUITE WARM.
MODEL SOLUTIONS DIVERGE SAT AND SUN. THE ECMWF BRINGS ANOTHER
COLD FRONT THROUGH THE REGION SAT AND KEEP THE REGION UNDER THE
INFLUENCE OF A WEAK UPPER LEVEL TROF SUN. MEANWHILE...THE GFS
KEEPS THE AREA MAINLY UNDER THE INFLUENCE OF SOUTHWESTERLY FLOW
ALOFT AROUND AN UPPER LEVEL RIDGE. BECAUSE OF THE LARGE MODEL
DIFFERENCES...I LEFT THE FORECAST FROM SAT TO THE END OF THE
EXTENDED PRETTY MUCH AS I INHERITED IT.
TEMPS WED AND THURS LOOK TO BE IN THE MID 80S TO MID 90S...WITH
SLIGHTLY COOLER WEATHER FRI. NOT QUITE SURE WHAT TEMPS WILL BE SAT
AND SUN. IF THE GFS IS CORRECT...UPPER 80S TO 90S. IF THE ECMWF
IS CORRECT...UPPER 70S TO MID 80S. FOR NOW...KEPT SAT AND SUN
TEMPS IN THE MID 80S TO AROUND 90...SORT OF A BLEND OF THE GFS AND
ECMWF. STC
&&
.AVIATION...
THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS SOUTHERN AND
WESTERN PORTIONS OF THE REGION...AND MOVE EASTWARD THROUGH THE
LATE AFTERNOON/EVENING HOURS. SOME OF THE STORMS WILL CONTAIN
HAIL AND ERRATIC...GUSTY WINDS AND HEAVY PRECIP...WHICH MAY
PRODUCE BRIEF IFR/LIFR FLIGHT CONDITIONS. VFR CONDITIONS WILL
PREVAIL OUTSIDE OF THUNDERSTORMS. MORE THUNDERSTORMS ARE
ANTICIPATED ACROSS THE REGION TOMORROW AFTERNOON/EVENING AHEAD OF
A COLD FRONT. STC
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 062/089 061/084 059/091 064/094 064/090 061/091 060/089
43/T 32/T 11/U 11/B 22/T 22/T 22/T
LVM 053/088 050/085 048/091 056/094 052/090 051/091 050/089
43/T 31/B 11/U 11/B 22/T 22/T 22/T
HDN 060/091 061/085 056/092 064/095 064/091 061/092 060/090
43/T 32/T 11/U 11/B 22/T 22/T 22/T
MLS 065/088 062/084 059/092 066/095 063/090 062/091 061/089
44/T 53/T 11/U 12/T 22/T 22/T 22/T
4BQ 061/090 060/084 056/090 062/093 063/089 061/090 060/088
53/T 43/T 11/U 12/T 22/T 22/T 33/T
BHK 060/084 060/079 055/086 061/089 063/085 062/086 061/084
54/T 54/T 12/T 22/T 22/T 22/T 33/T
SHR 056/090 056/083 052/089 059/093 058/089 056/090 055/088
43/T 32/T 11/U 11/U 22/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...SEVERE THUNDERSTORM WATCH 396 IN EFFECT UNTIL 11 PM MDT THIS
EVENING FOR ZONES 28>42-56>58-63>68.
WY...SEVERE THUNDERSTORM WATCH 396 IN EFFECT UNTIL 11 PM MDT THIS
EVENING FOR ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
221 PM MDT SUN JUL 7 2013
.SHORT TERM...VALID FOR MON AND TUE...
MAIN FORECAST ISSUE IS SEVERE WX POTENTIAL THIS AFTERNOON/EVENING
AND AGAIN TOMORROW.
WATER VAPOR IMAGERY SHOWS WSW FLOW ALOFT WITH SHORTWAVE ENERGY
APPROACHING FROM THE GREAT BASIN. A STRONGER TROF CAN BE SEEN
ALONG THE PAC NW COAST...AND THIS FEATURE WILL BE A PLAYER FOR US
MONDAY AND MONDAY NIGHT. PWATS IN PLACE ARE QUITE HIGH AND IN THE
VICINITY OF AN INCH...PERHAPS A BIT HIGHER IN OUR EAST. LOW LEVEL
E-SE WINDS ARE INCREASING...PROVIDING GREATER SHEAR AND LOW LEVEL
MOISTURE THAN WE SAW ON SATURDAY...AND LATEST 850MB ANALYSIS
SUGGESTS NOSE OF 850MB DEWPTS TO +13C IN FAR SE MT. WE REMAIN
UNDER RRQ OF 60KT H3 JET TO OUR NORTH...THUS MODEST SYNOPTIC
ASCENT IS PRESENT. OVERALL INGREDIENTS ARE IN PLACE FOR SEVERE
WEATHER LATE THIS AFTN AND EVENING. RECENT HRRR RUNS AGREE WITH
THIS ASSESSMENT AND HAVE BEEN CONSISTENT.
CONVECTION BEGINNING TO INITIATE OVER OUR SW MTNS WITH A FEW
LIGHTNING STRIKES NOTED SOUTH OF LIVINGSTON. A LONE CELL HAS
EMERGED FROM THE CU FIELD SE OF BROADUS. WILL BE INTERESTING TO
SEE WHAT SERN CELL WILL DO OVER THE NEXT COUPLE HOURS...SFC TEMPS
NEAR THE MID 80S MAY BE ENOUGH TO BREAK CAP THAT HAS BEEN IN
PLACE. OTHERWISE FOCUS SHOULD BE IN OUR WEST AS ACTIVITY SPREADS
OFF THE HIGH TERRAIN...SHIFTING EAST OVER TIME.
GREATEST SEVERE POTENTIAL THIS AFTN AND EVENING WILL BE EAST OF
BILLINGS IN REGION OF GREATER INSTABILITY AND SHEAR...ESPECIALLY
AS LOW LEVEL JET KICKS IN THIS EVENING. FOR MONDAY...OUR ENTIRE
AREA WILL BE AT AN ELEVATED RISK FOR SEVERE STORMS DUE TO
COMBINATION OF ASCENT FROM PAC NW TROF AND SURFACE COLD FRONT.
LARGE HAIL AND DAMAGING WINDS MAIN THREATS. HEAVY RAIN WILL
CONTINUE TO BE A POSSIBILITY BOTH TODAY AND TOMORROW DUE TO THE
MOISTURE RICH AIRMASS IN PLACE.
PASSAGE OF TROF...SURGE OF DRIER AIR AND SHIFT TO NW FLOW ALOFT
WILL SIGNAL THE BEGINNINGS OF A PATTERN SHIFT ON TUESDAY...AS THE
MOIST AIRMASS FINALLY GETS CLEANED OUT. COULD BE SOME MORNING
SHOWERS ON TUESDAY ALONG PV MAX...BUT OTHERWISE EXPECT DRIER AND
MORE STABLE CONDITIONS AS COOLER SFC RIDGE BUILDS IN FROM THE NW.
HAVE LOWERED POPS TUESDAY AFTERNOON AND NIGHT.
AS FOR TEMPS...MONDAY WILL BE THE WARMER OF THE NEXT TWO DAYS...
WITH PREFRONTAL CONDITIONS PERHAPS ALLOWING FOR TEMPS NEAR 90F.
TUESDAY WILL BE POSTFRONTAL AND COOLER WITH UPPER 70S TO MID 80S
FOR HIGHS...OR A LITTLE BELOW NORMAL.
JKL
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
MINIMAL CHANGES TO THE EXTENDED PERIOD...DUE IN LARGE PART TO
MODEL INCONSISTENCY FOR LATTER PORTIONS OF THE PERIOD.
THE PERIOD BEGINS WED UNDER AN UPPER LEVEL RIDGE...SO EXPECT HOT
AND MAINLY DRY CONDITIONS. MODELS DO SHOW SOME SHORTWAVE ACTIVITY
ROUNDING THE RIDGE...WITH SE LOW LEVEL FLOW OVER SOUTHEAST MONTANA
LATE WED AFTN/EVE...SO I KEPT A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE FORECAST ACROSS THE SE. RIDGING DOMINATES
THROUGH MUCH OF THE DAY THURS...SO HOT AND DRY CONDITIONS WILL
AGAIN BE THE RULE. A WEAK COLD FRONT...ALONG WITH SHORTWAVE
ACTIVITY...WILL MOVE ACROSS THE REGION THURS NIGHT...SO WE MAY SEE
SOME CONVECTIVE ACTIVITY THURS EVE/NIGHT OVER THE WESTERN
MOUNTAINS...AND OVER THE EAST...WHERE SHEAR IS BETTER AND THE
ATMOSPHERE IS LESS CAPPED. FRI LOOKS TO BE A TAD COOLER BEHIND THE
FRONT...BUT STILL QUITE WARM.
MODEL SOLUTIONS DIVERGE SAT AND SUN. THE ECMWF BRINGS ANOTHER
COLD FRONT THROUGH THE REGION SAT AND KEEP THE REGION UNDER THE
INFLUENCE OF A WEAK UPPER LEVEL TROF SUN. MEANWHILE...THE GFS
KEEPS THE AREA MAINLY UNDER THE INFLUENCE OF SOUTHWESTERLY FLOW
ALOFT AROUND AN UPPER LEVEL RIDGE. BECAUSE OF THE LARGE MODEL
DIFFERENCES...I LEFT THE FORECAST FROM SAT TO THE END OF THE
EXTENDED PRETTY MUCH AS I INHERITED IT.
TEMPS WED AND THURS LOOK TO BE IN THE MID 80S TO MID 90S...WITH
SLIGHTLY COOLER WEATHER FRI. NOT QUITE SURE WHAT TEMPS WILL BE SAT
AND SUN. IF THE GFS IS CORRECT...UPPER 80S TO 90S. IF THE ECMWF
IS CORRECT...UPPER 70S TO MID 80S. FOR NOW...KEPT SAT AND SUN
TEMPS IN THE MID 80S TO AROUND 90...SORT OF A BLEND OF THE GFS AND
ECMWF. STC
&&
.AVIATION...
THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS SOUTHERN AND
WESTERN PORTIONS OF THE REGION...AND MOVE EASTWARD THROUGH THE
LATE AFTERNOON/EVENING HOURS. SOME OF THE STORMS WILL CONTAIN
HAIL AND ERRATIC...GUSTY WINDS AND HEAVY PRECIP...WHICH MAY
PRODUCE BRIEF IFR/LIFR FLIGHT CONDITIONS. VFR CONDITIONS WILL
PREVAIL OUTSIDE OF THUNDERSTORMS. MORE THUNDERSTORMS ARE
ANTICIPATED ACROSS THE REGION TOMORROW AFTERNOON/EVENING AHEAD OF
A COLD FRONT. STC
&&
.PRELIMINARY POINT TEMP/POPS...
MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 062/089 061/084 059/091 064/094 064/090 061/091 060/089
43/T 32/T 11/U 11/B 22/T 22/T 22/T
LVM 053/088 050/085 048/091 056/094 052/090 051/091 050/089
43/T 31/B 11/U 11/B 22/T 22/T 22/T
HDN 060/091 061/085 056/092 064/095 064/091 061/092 060/090
43/T 32/T 11/U 11/B 22/T 22/T 22/T
MLS 065/088 062/084 059/092 066/095 063/090 062/091 061/089
44/T 53/T 11/U 12/T 22/T 22/T 22/T
4BQ 061/090 060/084 056/090 062/093 063/089 061/090 060/088
53/T 43/T 11/U 12/T 22/T 22/T 33/T
BHK 060/084 060/079 055/086 061/089 063/085 062/086 061/084
54/T 54/T 12/T 22/T 22/T 22/T 33/T
SHR 056/090 056/083 052/089 059/093 058/089 056/090 055/088
43/T 32/T 11/U 11/U 22/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1258 PM CDT SUN JUL 7 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 311 AM CDT SUN JUL 7 2013
IF MOISTURE CAN REMAIN IN PLACE THIS MORNING THEN ANOTHER ROUND OF
THUNDERSTORMS COULD DEVELOP THIS AFTERNOON AND TONIGHT. THE
DISTURBANCE AND ONGOING STORM ACTIVITY ACROSS WESTERN NEB SHOULD
EXIT THE FCST AREA TO EAST BY 20Z. THIS IMPLIES THAT THE STORMS
WEAKEN AND FALL APART AS THEY MOVE EAST AS INDICATED BY THE HRRR.
DEEP EASTERLIES SHOULD CONTINUE TODAY AS INDICATED BY THE VWP AT
KUDX AND THIS WOULD SUPPORT DESTABILIZATION ACROSS WESTERN NEB LATE
THIS MORNING THROUGH THIS EVENING WHICH IN TURN WOULD PROPAGATE EAST
THROUGH THE FCST AREA. THE FCST MIGHT BE AMBITIOUS WITH THE 40 POPS
BUT THIS IS A MARK DOWN FROM A 5 MODEL BLEND OF THE
ECM...GFS...SREF...NAM AND GEMREG. WATER VAPOR SUGGESTS ANOTHER
DISTURBANCE ACROSS WRN WY AND NRN UT WHICH COULD COME ACROSS THIS
AFTERNOON ON THE HEALS OF THE ONGOING DISTURBANCE.
MODEST DEEP LAYER SHEAR UP TO 250 MB WOULD PERHAPS SUPPORT ISOLATED
SEVERE STORMS WHICH WOULD PROBABLY PULSE SEVERE FROM TIME TO TIME
THIS AFTERNOON AND THIS EVENING. THE WEAKNESS IN THE LOW LEVEL WINDS
SUGGESTS THIS BEHAVIOR. SPC SUGGESTED A WEAKLY ORGANIZED MCS MIGHT
DEVELOP AND THIS CERTAINLY APPEARS IN LINE WITH THE 21Z OUTPUT OF
THE 06Z HRRR SHOWING A FAIRLY ORGANIZED LINE OF STORMS FROM KOGA TO
KVTN.
HIGHS IN THE UPPER 80S TO MID 90S ARE EXPECTED TODAY. THE MODELS
HAVE COME IN A FEW DEGREES COOLER FOR HIGHS TODAY VERSUS SATURDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 311 AM CDT SUN JUL 7 2013
ACTIVE FIRST HALF OF THE WEEK EXPECTED...AS THE AREA REMAINS ON
THE NORTHERN SIDE OF LARGE RIDGE OF UPPER HIGH PRESSURE CENTERED
ACROSS THE FOUR CORNERS REGION. WINDS ALOFT...MOISTURE...AND
INSTABILITY WILL BE FAVORABLE FOR TSTMS UNTIL THE RIDGE BEGINS TO
BUILD NORTH OVER THE AREA BY WEEKS END. TEMPERATURES ALOFT WILL
WARM THEN AS WELL AS A DECREASE IN WINDS ALOFT...CONDITIONS LESS
FAVORABLE FOR TSTM DEVELOPMENT.
A STATIONARY FRONT WILL OSCILLATE NORTH AND SOUTH THE FIRST HALF
OF THE WEEK...AND WILL BE A FOCUS FOR STORM DEVELOPMENT. OTHER
STORMS MAY FORM OFF THE HIGHER TERRAIN TO OUR WEST AND MOVE EAST
INTO THE AREA DURING THE EVENING HOURS. PWATS WILL BE RATHER
HIGH...WITH PLENTY OF LOW LEVEL MOISTURE IN PLACE TOO...SO SOME
DECENT RAINFALL TOTALS ARE POSSIBLE.
TEMPERATURES WILL BE WARM...AND THEN TURNING HOT BY WEEKS END AS
THE RIDGE BUILDS NORTH OVER THE AREA. HIGHS IN THE UPPER 80S TO
MID 90S WILL START THE WEEK...WITH MID 90S TO AROUND 100 TO FINISH
THE WEEK. DEPENDING ON DEW POINTS...WHICH CURRENTLY LOOK TO REMAIN
HIGH EAST OF HIGHWAY 83 AS THE HEAT BUILDS IN BY THE END OF THE
WEEK...WE COULD BE FLIRTING WITH HEAT ADVISORY CONDITIONS. WILL
CONTINUE TO MONITOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1257 PM CDT SUN JUL 7 2013
SMALL AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS CONTINUES
TO MOVE ACROSS NORTHERN NEBRASKA. A BRIEF IMPACT FOR KVTN...WITH
MVFR CONDITIONS...OTHERWISE THE AREA WILL SHIFT EAST AND EXIT
OVER THE NEXT FEW HOURS. MEANWHILE MORE MOISTURE...COMPARED TO
RECENT DAYS...WILL HELP TO ALLOW DEVELOPMENT OF THUNDERSTORMS
ACROSS THE WEST THIS AFTERNOON...WHICH WILL PROPAGATE EASTWARD
THIS EVENING. HAVE INCLUDED THUNDERSTORMS IN BOTH THE KLBF AND
KVTN TAF...HOWEVER HIGHER CONFIDENCE IS FOR KVTN. ALL ACTIVITY
WILL PUSH EAST OF THE TERMINALS OVERNIGHT...AS THE UPPER LEVEL
WAVE PUSHES EAST...RESULTING IN DECREASING CLOUDS AND LIGHT
WINDS...UNDER 10 KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
435 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A WARM AND HUMID AIRMASS WILL PERSIST ACROSS THE REGION THROUGH MUCH
OF THE WEEK WITH NEAR DAILY CHANCES OF SHOWERS AND THUNDERSTORMS
EXPECTED. THE HIGHEST CONCENTRATION OF SHOWERS AND STORMS WILL OCCUR
ON MONDAY AND AGAIN ON WEDNESDAY WHEN LOCALLY HEAVY RAINFALL IS
POSSIBLE. TEMPERATURES WILL REMAIN ON THE WARM SIDE...WITH HIGHS IN
THE 80S AND OVERNIGHT LOWS GENERALLY IN THE 60S.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 435 PM EDT SUNDAY...A WARM AND HUMID NIGHT EXPECTED ACROSS
THE AREA AS DEEPER SUBTROPICAL FLOW HAS PUSHED BACK NORTH AND EAST
INTO THE AREA AS EXPECTED. SCATTERED SHOWERS ALSO EXPECTED ON AND
OFF THROUGH THE EVENING AND NIGHTTIME HOURS AS HI-RES MODELS AND
THIS AFTERNOON`S RAP ANALYSIS SHOWING A WEAK SHORTWAVE MOVING
THROUGH THE FLOW ACROSS OUR AREA. MID-LEVEL MOISTURE CONVERGENCE
ALSO EVIDENT AS WEAK SURFACE FRONT SAGS SOUTH TO NEAR THE INTL
BORDER OVERNIGHT AND STALLS. WITH SUCH WEAK FEATURES QUITE
DIFFICULT TO TIME AREAL PLACEMENT AND INTENSITY OF PCPN...BUT PER
LATEST LAPS/RUC PROGS WILL ADVERTISE HIGH CHANCE POPS AND CONFINE
HIGHER THREAT OF THUNDER AND LOCALLY HEAVY RAINFALL TO OUR
SOUTHERN COUNTIES WHERE BEST MLCAPE PROFILES EXIST. AGAIN...A
MUGGY NIGHT EXPECTED AS SURFACE DEWPOINTS HOLD IN THE 60S TO
AROUND 70. WINDS LIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 435 PM EDT SUNDAY...BY MONDAY STILL LOOKING AT SCATTERED TO
WIDESPREAD SHOWERS AND THUNDER ACROSS MUCH OF THE AREA WITH WARM
AND MOIST AIRMASS IN PLACE ON THE WESTERN PERIPHERY OF STRONG
BERMUDA HIGH PRESSURE. WE`LL ALSO HAVE SOME ADDED IMPETUS FROM A
WEAKENING MID-LEVEL SHORTWAVE TROUGH LIFTING OUT OF THE LOWER
GREAT LAKES/OHIO VALLEY STATES THROUGH THE DAY. THIS COMBINED WITH
LIGHTLY VEERED PBL FLOW...LOWER NCAPE AND DEEP WCD VALUES IN
EXCESS OF 11 KFT ALL SUPPORT CONTINUED MENTION OF LOCALLY HEAVY
RAINFALL IN THE MORE ROBUST CELLS WHERE EFFICIENT PRECIPITATION
LOADING WILL BE LIKELY. WHILE I CAN`T COMPLETELY RULE OUT AN
ISOLATED SEVERE CELL...WITH SUCH HIGH WBZ VALUES I`M REALLY NOT
EXPECTING ANYTHING OTHER THAN SOME BRIEF GUSTY WINDS AND POSSIBLE
SMALL HAIL IN THE STRONGER CORES. HIGHS ON THE SEASONABLY WARM
SIDE...76 TO 84 OR CLOSE TO BLENDED BIAS-CORRECTED GUIDANCE.
EVENING SHOWERS AND STORMS THEN SLOWLY WANE IN AREAL COVERAGE AND
INTENSITY AS WE PROGRESS INTO MONDAY NIGHT AS SHORTWAVE EXITS EAST
AND WEAK RIDGING ALONG WITH LAYER OF DRIER MID-LEVEL AIR ADVECTS
INTO THE REGION. NO AIRMASS CHANGE...BUT ENOUGH DRYING SUCH THAT
MANY AREAS SHOULD TREND DRY BY TUESDAY MORNING. LOWS MAINLY IN THE
60S.
THEN MORE UNCERTAINTY AS WE HEAD INTO TUESDAY. FEELING IS TUESDAY
SHOULD BE MORE DRY THAN WET GIVEN MID-LEVEL DRY AIR AND WEAK
SUBSIDENCE ADVECTING ACROSS THE REGION...BUT EVIDENCE THAT SOME SORT
OF LOWER LEVEL MOISTURE BOUNDARY MAY LINGER ACROSS OUR EASTERN
COUNTIES. ECMWF MORE ROBUST WITH CHANCES PCPN THAN OTHER SHORT TERM
MODELS...BUT WILL DOWNPLAY AT THIS POINT OFFERING JUST SLIGHT TO
LOWER CHANCE POPS THROUGH THE DAY AND MAINLY ACROSS VT WHERE SOME
WIDELY SCATTERED ACTIVITY MAY OCCUR. HIGHS IN THE LOWER TO MID 80S.
BY TUESDAY NIGHT WARM AND HUMID CONDITIONS CONTINUE BUT MAINLY DRY
WITH LOSS OF INSOLATION. LOWS TO HOLD ON THE MILD SIDE AND MAINLY IN
THE 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 400 PM EDT SUNDAY...ACTIVE WEATHER DAY EXPECTED WEDS/THURS
AS POTENT TROF DEVELOPS ACRS THE NORTHERN GREAT LAKES AND SFC COLD
FRNT MOVES ACRS OUR CWA. THIS FRNT WL INTERACT WITH MODEST INSTABILITY
WITH LIS AROUND -4C AND CAPE VALUES BTWN 1500 TO 2000 J/KG.
ALSO...NOTED A RIBBON OF ENHANCED MID LVL WINDS...CREATING DEEP
LAYER SHEAR VALUES BTWN 30 AND 40 KNOTS...ESPECIALLY ACRS OUR
NORTHERN CWA ON WEDS AFTN. THE AREAL COVERAGE/INTENSITY OF STORMS
WL HIGHLY DEPEND UPON AMOUNT OF INSTABILITY/CLRING AND EXACT TRACK OF S/W
ENERGY. GIVEN...THE GOOD AGREEMENT IN MODELS WITH SYNOPTIC
FEATURES WL CONT TO MENTION HIGH CHC/LOW LIKELY POPS WEDS INTO
WEDS NIGHT...STILL A MINOR TIMING DIFFERENCE BTWN THE FASTER GFS
AND SLOWER ECMWF. WEAK SUBSIDENCE AND HIGH PRES TRIES TO BUILD
ACRS OUR CWA LATE THURS INTO FRIDAY...WITH A BRIEF DRY SPELL
POSSIBLE. LOTS OF UNCERTAINTY ASSOCIATED WITH NEXT SYSTEM FRIDAY
INTO NEXT WEEKEND...WITH GFS SHOWING MID/UPPER CLOSED CIRCULATION
ACRS THE GREAT LAKES RETROGRADING SW TWD TEXAS BY SUNDAY...WHILE
THE ECMWF SPLITS THE SYSTEM INTO TWO DISTINCT CLOSED CIRCULATIONS
WITH GREATER IMPACT ACRS OUR FA. GIVEN THE UNCERTAINTY IN THE
EVOLUTION OF THIS COMPLEX SYNOPTIC PATTERN...WL MENTION CHC POPS
NEXT WEEKEND. IF THE ULVL PATTERN VERIFIES ON THE ECMWF AND DEEP
TROPICAL MOISTURE IS ADVECTED BACK INTO THE NE CONUS...HYDRO WL
NEED TO BE WATCHED CLOSELY...FOR THE POTENTIAL FOR HEAVY RAINFALL.
PROGGED 85H TEMPS AHEAD OF BOUNDARY RANGE BTWN 14-16C ON
WEDS/THURS...BEFORE COOLING BACK BTWN 10-12C ON
FRIDAY...SUPPORTING HIGHS MID/UPPER 80S MID WEEK TO M70S TO L80S
BY NEXT FRIDAY. LOWS WL BE MAINLY IN THE U50S MTNS TO M60S
VALLEYS.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
THROUGH 18Z MONDAY...CRNT RADAR SHOWS RAIN SHOWERS INCREASING IN
AREAL COVERAGE/INTENSITY ACRS NORTHERN NY AND INTO THE WESTERN CPV
ATTM. EXPECT THIS ACTIVITY TO IMPACT OUR TAF SITES BTWN 18Z-22Z
THIS AFTN WITH A BRIEF SHOWER AND POSSIBLE MVFR CONDITIONS IN THE
HEAVIER SHOWER. THE POTENTIAL FOR ADDITIONAL SHOWERS WITH AN
EMBEDDED STORM WL CONT OVERNIGHT INTO MONDAY...AS SEVERAL EMBEDDED
S/W`S INTERACT WITH SFC INSTABILITY. DIFFICULT TO PIN POINT EXACT
TIMING AND LOCATION OF STORMS...THEREFORE USED VCSH THRU MOST OF
THE NIGHT. ALSO...GIVEN THE INCREASED SFC DWPTS AND BL
MOISTURE...AREAS OF HZ/BR WL BE POSSIBLE ESPECIALLY AT SITES THAT
RECIEVE RAIN THIS AFTN AND AT KMSS. SOUTH TO SOUTHWEST WINDS AT 4
TO 8 KNOTS THIS AFTN...WL BECM LIGHT TRRN DRIVEN TONIGHT.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...SCATTERED SHOWERS AND
THUNDERSTORMS WL BE POSSIBLE MONDAY AND AGAIN ON WEDS/THURS. THIS
ACTIVITY WL HAVE THE POTENTIAL TO PRODUCE BRIEF PERIODS OF MVFR
CONDITIONS ALONG WITH LOCALIZED GUSTY WINDS IN AND NEAR STORMS.
ALSO...LOOK FOR SOME BR/FOG TO DEVELOP IF SKIES CAN
CLR...ESPECIALLY AT MPV/SLK BTWN 07-11Z...WITH GENERALLY SOUTH TO
SOUTHWEST WINDS THRU THE PERIOD.
&&
.HYDROLOGY...
AS OF 435 PM EDT SUNDAY... LOCALLY HEAVY RAINFALL WILL REMAIN
POSSIBLE ACROSS THE SOUTHERN PORTIONS OF THE FORECAST AREA THIS
EVENING...AND ACROSS THE ENTIRE AREA ON MONDAY. WHILE WIDESPREAD
OR ORGANIZED AREAS OF FLASH FLOODING ARE NOT EXPECTED...WCD VALUES
WILL REMAIN QUITE HIGH ALONG WITH HIGH COLUMNAR MOISTURE PROFILES.
THUS POINT TOTALS IN EXCESS OF ONE INCH IN AN HOUR OR LESS WILL BE
POSSIBLE...WHICH CHOULD LEAD TO LOCALIZED HYDROLOGICAL
CONCERNS...ESPECIALLY ON MONDAY WHEN BOUNDARY LAYER FLOW WILL BE
QUITE LIGHT BELOW 850 MB.
&&
.EQUIPMENT...
AS OF 415 AM EDT SUNDAY...THE KTYX RADAR IS DOWN UNTIL FURTHER
NOTICE. TECHS HAVE ORDERED PARTS...WHICH SHOULD ARRIVE ON MONDAY
AND THE RADAR SHOULD BE RETURNED TO SERVICE BY TUESDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER
HYDROLOGY...JMG
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BUFFALO NY
332 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A PERSISTENT TROUGH OF LOW PRESSURE WILL GRADUALLY SLIDE EASTWARD
ACROSS THE REGION EARLY NEXT WEEK. THIS WILL RESULT IN CONTINUED
UNSETTLED WEATHER THROUGH MID-WEEK BEFORE DRIER AIR FINALLY
ARRIVES BY THE END OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE
GREAT LAKES.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF MID-AFTERNOON...RADAR SHOWS MOST OF WESTERN NEW YORK IS
SHOWER-FREE...WITH JUST A FEW SHOWERS STARTING TO DEVELOP ACROSS
WESTERN PORTIONS OF THE SOUTHERN TIER. MEANWHILE...THE MOST
NOTEWORTHY FEATURE IS CONVECTION DEVELOPING ACROSS CENTRAL
PENNSYLVANIA. BOTH THE GFS/HRRR HANDLED AN INITIAL WAVE OF
CONVECTION EARLY THIS MORNING...AND IT APPEARS THESE MODELS ALSO
HAVE A GOOD HANDLE ON THE NEXT WAVE AS WELL. USING THIS
GUIDANCE...EXPECT THAT ORGANIZED CONVECTION WILL TRACK TO OUR
SOUTHEAST THROUGH EARLY EVENING. THIS LEAVES ONLY SUBTLE SURFACE
BOUNDARIES TO PROVIDE THE FOCUS NEEDED FOR SHOWERS AND THUNDERSTORMS
LATE THIS AFTERNOON. THERE WILL BE LAKE BREEZES BOTH EAST OF LAKE
ERIE...AND SOUTH AND EAST OF THE EASTERN HALF OF LAKE ONTARIO. IN
EACH CASE...EXPECT ANY SHOWERS TO BE SCATTERED IN NATURE...WITH A
FEW THUNDERSTORMS ALSO POSSIBLE. NE OF LAKE ONTARIO AND LAKE
ERIE...EXPECT THE WELL DEVELOPED SW FLOW TO STABILIZE THE BOUNDARY
LAYER...AND KEEP THE BUFFALO METRO AREA DRY THIS AFTERNOON...EVEN IF HIGH
CLOUDS FROM UPSTREAM LIMIT SUNSHINE.
FOR THIS EVENING...CONVECTION ACROSS PENNSYLVANIA SHOULD REMAIN TO
THE SOUTH...WITH MOST OF THE DIURNALLY DRIVEN SHOWERS LIKELY TO
TAPER OFF. HOWEVER...THERE IS SOME INDICATION THAT SHOWERS
MAY DEVELOP ACROSS CENTRAL NEW YORK IF AN OUTFLOW FROM THE
CONVECTION TO THE SOUTH INTERACTS WITH LINGERING INSTABILITY IN THE
REGION. THIS AREA WILL ALSO BE UNDERNEATH A DIFLUENT FLOW ALOFT
AHEAD OF AN APPROACHING UPPER LOW...WHICH WOULD ENHANCE THE
CONVECTIVE POTENTIAL. THIS POSSIBILITY IS SHOWN BY THE HRRR AND 12Z
RGEM...AND TO A LESSER EXTENT 12Z GFS/NAM. IT IS MOST LIKELY TO STAY
SE OF OUR CWA...BUT MAY REACH INTO THE FINGER LAKES REGION. THIS
FEATURE BEARS WATCHING GIVING THE CONTINUED MOIST ENVIRONMENT WITH
PRECIPTABLE WATER VALUES STILL IN THE 1.75 INCH RANGE. SLOW MOVING
THUNDERSTORMS COULD PRODUCE LOCALLY HEAVY RAINFALL AND FLOODING.
OTHERWISE...AN UPPER LEVEL TROF IS FORECAST TO SLOWLY LIFT ACROSS
WESTERN PENNSYLVANIA OVERNIGHT. THIS WILL BRING A CHANCE OF MORE
GENERAL SHOWER ACTIVITY...HOWEVER IT SHOULD BE SOMEWHAT SPOTTY IN
NATURE. AS HAS BEEN THE CASE...SOME PATCHY FOG IS POSSIBLE IN THE
SOUTHERN TIER VALLEYS...AND EAST OF LAKE ONTARIO. LOWS SHOULD
RANGE FROM THE MID 60S TO AROUND 70.
ON MONDAY...THE CLOSED UPPER LEVEL LOW WILL GRADUALLY OPEN AS IT
SLIDES TO THE EAST. THIS FEATURE WILL RESULT IN A CONTINUED THREAT
FOR SHOWERS DURING THE DAY MONDAY...AS DAYTIME INSTABILITY ENHANCES
SHOWER ACTIVITY. SLIGHTLY COOLER TEMPERATURES ALOFT SHOULD ALLOW
STORMS TO DEVELOP LIGHTNING A BIT MORE QUICKLY THAN THE PAST COUPLE
DAYS. AS THE OPENING TROF EXITS TO THE EAST...EXPECT DRYING WITH THE
SUBSTANCE ASSOCIATED WITH THE EXITING FEATURE. AS A RESULT...SHOWERS
AND THUNDERSTORMS SHOULD TAPER OFF FROM WEST TO EAST DURING THE
AFTERNOON HOURS. TEMPERATURES WILL BE A TAD COOLER...WITH HIGHS INT
HE UPPER 70S TO LOWER 80S. IT WILL CONTINUE TO BE MOIST RESULTING IN
CONTINUED MUGGY CONDITIONS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH THURSDAY NIGHT/...
AS THE AXIS OF THE UPPER TROUGH WILL HAVE PASSED TO THE EAST OF
THE FORECAST AREA...EXPECT A SHARP DROP OFF IN POPS FOR MONDAY
NIGHT. WARM ADVECTION THROUGHOUT THE BOUNDARY LAYER WILL ARRIVE IN
WESTERN AND SOUTHERN NY ON TUESDAY WITH INCREASING BUT STILL LOW
CHANCE OF THUNDERSTORMS ACROSS THE SOUTHERN TIER...MAINLY DURING
TUESDAY AFTERNOON. TEMPS MONDAY NIGHT WILL BE IN THE LOWER TO MID
60S ACROSS THE SOUTHERN TIER AND TUG HILL...AND MID 60S TO NEAR 70
FOR THE LAKE PLAINS AND URBAN AREAS. HIGHS ON TUESDAY WILL RISE A
NOTCH TO THE LOWER TO MID 80S.
A TROUGH MOVING ACROSS ONTARIO PROVINCE WILL SPAWN A SURFACE LOW
OVER THE UPPER MID WEST ON TUESDAY TO SOUTH OF JAMES BAY ON
WEDNESDAY. 35 TO 40 KNOT WINDS AT 850MB ACROSS THE CENTRAL GREAT
LAKES WILL FORM A WARM FRONT ASSOCIATED WITH THE SURFACE LOW.
INCREASING MOISTURE AHEAD OF THE WARM FRONT...PRECIPITABLE WATER
RISING BACK TO NEAR 2 INCHES...AND ADDED LIFT IN THE VICINITY OF THE
SHORT WAVE TROUGH WILL BRING A GOOD CHANCE FOR SHOWERS AND
THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY. UNSETTLED WEATHER WILL
CONTINUE WEDNESDAY NIGHT AS A COLD FRONT...TRAILING SOUTH OF LOW
PRESSURE NEAR JAMES BAY...PUSHES EAST ACROSS THE STATE. TEMPS
TUESDAY NIGHT WILL RANGE FROM THE MID 60S ACROSS THE SOUTHERN TIER
AND TUG HILL...TO LOWER 70S FOR THE LAKE PLAINS AND URBAN AREAS.
HIGHS ON WEDNESDAY WILL BE SIMILAR TO TUESDAY...LOWER TO MID
80S...EVEN WITH THICKER CLOUD AND OCCURRENCE OF PRECIP.
DRIER AND MARGINALLY COOLER AIR WILL ARRIVE IN THE POSTFRONTAL
AIRMASS ON THURSDAY WITH LOWER CHANCE POPS AND PARTIAL CLEARING.
EXPECT HIGHS IN THE MID TO UPPER 70S ON THURSDAY AND LOWS THURSDAY
NIGHT IN THE UPPER 50S TO LOWER 60S AS SKIES CLEAR FURTHER.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
THE UPPER TROUGH ACROSS ONTARIO WILL STALL AND DIG FARTHER
SOUTH...DEVELOPING A CUTOFF LOW ACROSS THE EASTERN U.S. THIS LOW
WILL DROP FARTHER TO THE SOUTH ON THE WEEKEND AND BLOCK THE WARMER
AIR FROM THE NATION`S MIDSECTION...ALSO TAPPING INTO MOISTURE FROM
THE WESTERN ATLANTIC. FRIDAY AND FRIDAY NIGHT SHOULD REMAIN DRY
AND QUITE COOLER WITH HIGHS IN THE 70S AND LOWS IN THE UPPER 50S
TO LOW 60S. HIGHER CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
ARRIVE DURING SATURDAY AND SUNDAY AS THE SOUTHEASTERLY LOW LEVEL
FLOW FROM THE MID ATLANTIC INTERACTS WITH THE MID AND UPPER LEVEL
TROUGH. HIGH TEMPS FOR THE WEEKEND WILL BE IN THE MID TO UPPER 70S
ON SATURDAY AND THE UPPER 70S TO LOWER 80S ON SUNDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
EXPECT MAINLY VFR CONDITIONS FOR THE REMAINDER OF THIS
AFTERNOON...WITH LINGERING MVFR CIGS LIKELY TO LIFT AND SCATTER.
THERE MAY BE A FEW SHOWERS AND THUNDERSTORMS...BUT EXPECT THE SW
FLOW TO KEEP THESE OUT OF BUF/IAG/ART/ROC...WHICH TEND TO BE
SHADOWED IN THIS FLOW. JHW MAY SEE A THUNDERSTORM THIS
AFTERNOON...BUT CONFIDENCE IS RELATIVELY LOW GIVEN STORMS SHOULD
BE QUITE SCATTERED.
FOR TONIGHT...EXPECT MORE SCATTERED SHOWERS AS THE UPPER LOW MOVES
CLOSER TO THE REGION. THERE WILL BE QUITE A BIT OF LOW LEVEL
MOISTURE IN PLACE...BUT AS LONG AS WINDS PERSIST AND THE MID AND
HIGH CLOUDS REMAIN...EXPECT CIGS TO REMAIN MAINLY IN THE VFR
RANGE. THIS SAID...ANY PROLONGED CLEARING WOULD LIKELY RESULT IN
LOW CLOUDS AND FOG...WITH THE BEST CHANCE FOR THIS AT JHW/ART.
THERE WILL BE A CONTINUED THREAT FOR SHOWERS AND POSSIBLY A
THUNDERSTORM ON MONDAY. EXPECT MAINLY VFR CONDITIONS EXCEPT IN
STORMS WHERE HEAVY RAINS COULD LOWER VSBY TO 2SM OR LESS.
OUTLOOK...
MONDAY NIGHT THROUGH WEDNESDAY...MAINLY VFR WITH SCATTERED
SHOWERS AND THUNDERSTORMS AND ASSOCIATED BRIEF MVFR/IFR
CONDITIONS.
THURSDAY AND FRIDAY...VFR.
&&
.MARINE...
SOUTHWEST WINDS HAVE INCREASED ON LAKE ERIE AND WESTERN LAKE ONTARIO...HOWEVER
THE STRONGEST WINDS ARE ON LAND WHERE WINDS ALOFT CAN MIX MORE
READILY. WEBCAMS AND OBS SHOW ONLY MODEST WAVES WITH NO WHITE
CAPS ALONG THE NEARSHORES OF LAKE ERIE. THERE MAY BE A DECENT CHOP ON
WESTERN LAKE ONTARIO...DUE TO SW GUSTS NEAR THE IMMEDIATE
SHORELINE...BUT WAVES SHOULD REMAIN WELL BELOW 4 FT SINCE WINDS
WILL DIMINISH OFFSHORE.
LIGHT TO MODERATE SOUTHWEST WINDS WILL CONTINUE TONIGHT THROUGH
MONDAY WITH CHOPPY WAVE ACTION AT TIMES ON BOTH LAKE...BUT
CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL
MARINE...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
158 PM EDT SUN JUL 7 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST OVER THE REGION THROUGH
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY DURING
THE AFTERNOON. SINCE THE AIRMASS REMAINS VERY MOIST ANY
THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL. THE UPPER
LEVEL TROUGH WILL EXIT THE NORTHEASTERN UNITED STATES MONDAY NIGHT
BRINGING A BRIEF END TO THE RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
845 AM UPDATE...
EARLY MRNG MCS HAS MOVD EAST AND IS ENTERING WRN NEW
ENGLAND...WITH FCST AREA UNDER PC SKIES. TDA`S SCENARIO IS NOT
MUCH DIFFERENT FROM PREV DAYS. UPR LOW OVER INDIANA THIS MRNG
WITH S/WV`S ROTATING NEWD FROM THE ERN OH VLY INTO THE NE U.S..
NXT S/WV IS OVER WRN WV WHICH WILL BE HEADING NEWD TWDS WRN NY LATE
TDA. OTHER THAN THIS FEATURE...THERE IS NOT MUCH TO FOCUS
CONVECTIVE DVLPMNT TDA OTHER THAN ANY MESO-BETA BNDRYS AND TRRN
FEATURES.
IN THE NEAR TERM WE LOWERED POPS INTO EARLY AFTN AND REMOVED ANY
QPF BEFORE 18Z...THEN CHC POPS THIS AFTN FOR SCT SHRA/TSRA. WIND
SHEAR TDA IS MARGINAL FOR ORGANIZED STORMS AND IS ACTUALLY LOWERING
THIS MRNG INTO EARLY AFTN...BUT INCREASES TO MARGINALLLY
SUPPORTIVE VALUES ACRS WRN ZONES LATE TDA WITH APRCH OF NXT S/WV.
GIVEN MOIST CONDITIONS...LCL +RA WILL BE MAIN THREAT WITH ANY
STORMS TDA. PREV BLO...
630 AM UPDATE...
JUST DID ANOTHER MAJOR RE-WORK OF THE POPS GRIDS AS S/WV IS
EXITING STAGE RIGHT AT THIS TIME, TAKING THE STORMS WITH IT IN THE
NEXT HR. BASED ON LATEST RUC FCST AND CURRENT TRENDS NOT EXPECTING
MUCH IN THE WAY OF SHOWERS TO GET IN HERE BFR 15Z AND ONLY SCTD,
AT BEST, AFTER THAT TIME.
520 AM UPDATE...
QUICK UPDATE TO UP POPS ACRS UPSTATE NY TO 50% FOR CLUSTER OF
TSTMS MVG THRU NRN ZONES. ALSO UPPED QPF TO AROUND 0.25 INCHES
BASIN-AVERAGE THRU 12Z THO LOCALLY HIGHER AMNTS MAY EXIST.
330 AM UPDATE...
BERMUDA RIDGE CONTS TO SPIN OFF THE ATLANTIC COAST WITH PLENTIFUL
MOISTURE BEING PUMPED INTO CWA FM GOM. UL TROF/LOW IS ON THE MV AS
RIDGE IS WEAKENING. S/WV LOCATED ACRS OH/KY AREA WL APPCH THE FA
THIS AFTN AND RESULT IN A GOOD CHC FOR SHRA/TSRA ACTIVITY. THUS WL
GO WITH LKLY POPS ACRS WRN ZONES ARND 18Z OR SO THEN DIMINISHING AFT
THAT AS WV PASSES OFF TO THE WEST AND MID-LVL LAPSE RATES WEAKEN.
AS FOR SVR POTENTIAL, EXPECT ONLY A STRONG STORM OR TWO AS 0-6KM
BULK SHEAR VALUES WEAKEN THRU THE DAY. ANY TSTM THAT CAN DVLP WL HV
THE POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS AND LOCALIZED FLOODING
AND THIS WL LKLY BE THE MAIN THREAT FOR THIS AFTN.
H8 TEMPS TO ARND 17C TDA WL YIELD HIGHS IN THE M/U 80S SIMILAR TO
YDA.
FOR TONIGHT, UL LOW WL OPEN UP ACRS NRN OHIO BY 06Z AND BEGIN TO
EJECT EAST WITH SCTD THUNDER RMNG ACRS THE REGION THRU 12Z MONDAY.
EXPECTING OVRNGT MINS TO RMN UP IN THE U60S WITH DWPTS RMNG JUST A
DEGREE OR TWO LOWER.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
330 AM UPDATE...
UPR TROF WL BE EJECTING OUT DRG THE DAY ON MONDAY WITH PW VALUES
GRADUALLY DROPPING THRU THE AFTN. POTENTIAL EXISTS FOR LCLY HVYR
RAINFALL THRU THE COURSE OF THE DAY WITH UL TROF INTERACTING WITH
FRONTAL BNDRY ACRS THE NERN U.S. THIS, IN ADDITION TO SATURATED SOIL
CONDS WL BRING A HEIGHTENED THREAT FOR FLOODING ON MONDAY. THUS, WL
HIGHLIGHT THREAT IN THE HWO.
PCPN SHUD GRADUALLY WIND DOWN MON NGT AS FLOW TRANSITIONS TO A MORE
ZONAL FLOW ALOFT. DIURNAL CONVECTION WL ONCE AGAIN BE POSSIBLE TUE
AFTN BFR TAPERING OFF TUE NGT, AHD OF NEXT H5 TROF HEADED IN FM THE
WEST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS ARE IN EXCELLENT AGREEMENT THROUGH THE
EXTENDED PERIOD. WED NIGHT THROUGH THURSDAY, UPPER LEVEL TROF WILL
DROP THROUGH THE GREAT LAKES AS SFC COLD FRONT PASSES THROUGH THE
AREA LATE WED NIGHT THROUGH THURSDAY MORNING. WILL CONTINUE WITH
LIKELY POPS INTO THURSDAY MORNING THEN DROP BACK TO DRY WEST AND
JUST CHC EAST BY THURSDAY AFTERNOON.
THURSDAY NIGHT THROUGH SUNDAY...UPPER LEVEL TROF CUTS OFF OVER
THE REGION THEN RETROGRADES LATE IN THE PERIOD AS WESTERN ATLANTIC
RIDGE BUILDS. AT THE SFC, HIGH PRES WILL BUILD OVER THE AREA
AND DOMINATE OUR WEATHER THROUGH FRIDAY NIGHT WITH PRIMARILY DRY
CONDITIONS. SATURDAY THROUGH SUNDAY, AN INCREASINGLY MOIST
SOUTHEAST FLOW WILL DEVELOP LEADING TO HUMID CONDITIONS AND CHC
POPS FOR CONVECTION. HIGHEST POPS WILL BE OVER THE EASTERN CWA
IN AN AREA OF BETTER MOISTURE AND OROGRAPHIC LIFT.
TEMPS THROUGH THE PERIOD WILL BE NEAR SEASONAL NORMS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A VERY COMPLEX FORECAST NEXT 24 HRS. UPPER LEVEL LOW IN THE OHIO
VALLEY WILL TRACK NORTHEAST INTO CENTRAL PA BY MONDAY. FOR THIS
AFTERNOON, SCATTERED CONVECTION IS EXPECTED ALONG THE LAKE PLAIN
THEREFORE INCLUDED 4 HOUR TEMPS GROUP FOR MVFR RAIN SHOWERS AT
KRME/KSYR. THUNDERSTORMS ARE ALSO A POSSIBILITY BUT NOT INCLUDED
AT THIS TIME. FOR THE REMAINDER OF TAFS, WAVE IN SOUTHWEST PA MAY
INITIATE CONVECTION LATE THIS AFTERNOON THROUGH EARLY EVENING.
INCLUDED TEMPO GROUP FOR MVFR SHOWERS BUT AGAIN THUNDERSTORMS ARE
A POSSIBILITY. FOR A WHILE THIS EVENING CONDITIONS WILL BE
PRIMARILY VFR BUT MVFR STRATUS IS EXPECTED LATE TONIGHT AT ALL
SITES AS DEEPER MOISTURE SETTLES BACK OVER THE AREA WITH UPPER
LEVEL FEATURE. FOR MONDAY, JUST WENT WITH CATEGORICAL SHOWERS WITH
MVFR CIGS AFTER 15Z.
SOUTHWEST WINS AT 5-10 KNOTS BECOMING LIGHT OVERNIGHT THEN
SOUTHWEST AGAIN ON MONDAY.
.OUTLOOK...
MONDAY NIGHT...MVFR RESTRICTIONS PSBL IN EARLY MRNG STRATUS/FOG.
TUESDAY THROUGH TUESDAY NIGHT...PRIMARILY VFR.
WEDNESDAY THROUGH THURSDAY...RESTRICTIONS IN SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS.
THURSDAY NIGHT THROUGH FRIDAY...PRIMARILY VFR ALTHOUGH VALLEY FOG
IS POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...
SHORT TERM...PVN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1206 PM EDT SUN JUL 7 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PERSIST OVER THE REGION THROUGH
MONDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS, PRIMARILY DURING
THE AFTERNOON. SINCE THE AIRMASS REMAINS VERY MOIST ANY
THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL. THE UPPER
LEVEL TROUGH WILL EXIT THE NORTHEASTERN UNITED STATES MONDAY NIGHT
BRINGING A BRIEF END TO THE RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
845 AM UPDATE...
EARLY MRNG MCS HAS MOVD EAST AND IS ENTERING WRN NEW
ENGLAND...WITH FCST AREA UNDER PC SKIES. TDA`S SCENARIO IS NOT
MUCH DIFFERENT FROM PREV DAYS. UPR LOW OVER INDIANA THIS MRNG
WITH S/WV`S ROTATING NEWD FROM THE ERN OH VLY INTO THE NE U.S..
NXT S/WV IS OVER WRN WV WHICH WILL BE HEADING NEWD TWDS WRN NY LATE
TDA. OTHER THAN THIS FEATURE...THERE IS NOT MUCH TO FOCUS
CONVECTIVE DVLPMNT TDA OTHER THAN ANY MESO-BETA BNDRYS AND TRRN
FEATURES.
IN THE NEAR TERM WE LOWERED POPS INTO EARLY AFTN AND REMOVED ANY
QPF BEFORE 18Z...THEN CHC POPS THIS AFTN FOR SCT SHRA/TSRA. WIND
SHEAR TDA IS MARGINAL FOR ORGANIZED STORMS AND IS ACTUALLY LOWERING
THIS MRNG INTO EARLY AFTN...BUT INCREASES TO MARGINALLLY
SUPPORTIVE VALUES ACRS WRN ZONES LATE TDA WITH APRCH OF NXT S/WV.
GIVEN MOIST CONDITIONS...LCL +RA WILL BE MAIN THREAT WITH ANY
STORMS TDA. PREV BLO...
630 AM UPDATE...
JUST DID ANOTHER MAJOR RE-WORK OF THE POPS GRIDS AS S/WV IS
EXITING STAGE RIGHT AT THIS TIME, TAKING THE STORMS WITH IT IN THE
NEXT HR. BASED ON LATEST RUC FCST AND CURRENT TRENDS NOT EXPECTING
MUCH IN THE WAY OF SHOWERS TO GET IN HERE BFR 15Z AND ONLY SCTD,
AT BEST, AFTER THAT TIME.
520 AM UPDATE...
QUICK UPDATE TO UP POPS ACRS UPSTATE NY TO 50% FOR CLUSTER OF
TSTMS MVG THRU NRN ZONES. ALSO UPPED QPF TO AROUND 0.25 INCHES
BASIN-AVERAGE THRU 12Z THO LOCALLY HIGHER AMNTS MAY EXIST.
330 AM UPDATE...
BERMUDA RIDGE CONTS TO SPIN OFF THE ATLANTIC COAST WITH PLENTIFUL
MOISTURE BEING PUMPED INTO CWA FM GOM. UL TROF/LOW IS ON THE MV AS
RIDGE IS WEAKENING. S/WV LOCATED ACRS OH/KY AREA WL APPCH THE FA
THIS AFTN AND RESULT IN A GOOD CHC FOR SHRA/TSRA ACTIVITY. THUS WL
GO WITH LKLY POPS ACRS WRN ZONES ARND 18Z OR SO THEN DIMINISHING AFT
THAT AS WV PASSES OFF TO THE WEST AND MID-LVL LAPSE RATES WEAKEN.
AS FOR SVR POTENTIAL, EXPECT ONLY A STRONG STORM OR TWO AS 0-6KM
BULK SHEAR VALUES WEAKEN THRU THE DAY. ANY TSTM THAT CAN DVLP WL HV
THE POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS AND LOCALIZED FLOODING
AND THIS WL LKLY BE THE MAIN THREAT FOR THIS AFTN.
H8 TEMPS TO ARND 17C TDA WL YIELD HIGHS IN THE M/U 80S SIMILAR TO
YDA.
FOR TONIGHT, UL LOW WL OPEN UP ACRS NRN OHIO BY 06Z AND BEGIN TO
EJECT EAST WITH SCTD THUNDER RMNG ACRS THE REGION THRU 12Z MONDAY.
EXPECTING OVRNGT MINS TO RMN UP IN THE U60S WITH DWPTS RMNG JUST A
DEGREE OR TWO LOWER.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
330 AM UPDATE...
UPR TROF WL BE EJECTING OUT DRG THE DAY ON MONDAY WITH PW VALUES
GRADUALLY DROPPING THRU THE AFTN. POTENTIAL EXISTS FOR LCLY HVYR
RAINFALL THRU THE COURSE OF THE DAY WITH UL TROF INTERACTING WITH
FRONTAL BNDRY ACRS THE NERN U.S. THIS, IN ADDITION TO SATURATED SOIL
CONDS WL BRING A HEIGHTENED THREAT FOR FLOODING ON MONDAY. THUS, WL
HIGHLIGHT THREAT IN THE HWO.
PCPN SHUD GRADUALLY WIND DOWN MON NGT AS FLOW TRANSITIONS TO A MORE
ZONAL FLOW ALOFT. DIURNAL CONVECTION WL ONCE AGAIN BE POSSIBLE TUE
AFTN BFR TAPERING OFF TUE NGT, AHD OF NEXT H5 TROF HEADED IN FM THE
WEST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS ARE IN EXCELLENT AGREEMENT THROUGH THE
EXTENDED PERIOD. WED NIGHT THROUGH THURSDAY, UPPER LEVEL TROF WILL
DROP THROUGH THE GREAT LAKES AS SFC COLD FRONT PASSES THROUGH THE
AREA LATE WED NIGHT THROUGH THURSDAY MORNING. WILL CONTINUE WITH
LIKELY POPS INTO THURSDAY MORNING THEN DROP BACK TO DRY WEST AND
JUST CHC EAST BY THURSDAY AFTERNOON.
THURSDAY NIGHT THROUGH SUNDAY...UPPER LEVEL TROF CUTS OFF OVER
THE REGION THEN RETROGRADES LATE IN THE PERIOD AS WESTERN ATLANTIC
RIDGE BUILDS. AT THE SFC, HIGH PRES WILL BUILD OVER THE AREA
AND DOMINATE OUR WEATHER THROUGH FRIDAY NIGHT WITH PRIMARILY DRY
CONDITIONS. SATURDAY THROUGH SUNDAY, AN INCREASINGLY MOIST
SOUTHEAST FLOW WILL DEVELOP LEADING TO HUMID CONDITIONS AND CHC
POPS FOR CONVECTION. HIGHEST POPS WILL BE OVER THE EASTERN CWA
IN AN AREA OF BETTER MOISTURE AND OROGRAPHIC LIFT.
TEMPS THROUGH THE PERIOD WILL BE NEAR SEASONAL NORMS.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
MAIN CONCERN HEADING INTO TODAY WILL BE POSSIBLE SHWRS/STORM
DEVELOPMENT LATER THIS AFTERNOON AS UPPER STORM SYSTEM APPROACHES
FROM THE SOUTHWEST. FOR NOW...FEEL BULK OF THE MORNING HRS SHOULD
BE PRECIP FREE WITH ACTIVITY THEN DEVELOPING AFTER 18Z. FCST
GUIDANCE SUGGESTING WEAK INSTABILITY LATER THIS AFTERNOON AND THUS
HAVE ADVERTISED A 3 HR TEMPO GROUP FOR THUNDER AT ALL SITES.
MOVING INTO TONIGHT...DIURNAL STORMS SHOULD COME TO AN END BEFORE
00Z WITH BULK OF ACTIVITY THEN TRANSITIONING BACK TO PLAIN SHWRS.
BEYOND 06Z...GUIDANCE SUGGESTS WIDESPREAD RESTRICTIONS DEVELOPING
HOWEVER CONTINUED SOUTHWEST FLOW LENDS ONLY MARGINAL CONFIDENCE OF
THIS SCENARIO DEVELOPING. DESPITE THIS...HAVE NUDGED TOWARDS
LOW-END MVFR UNTIL BETTER CONFIDENCE ARRIVES WITH FUTURE MODEL
GUIDANCE.
.OUTLOOK...
MONDAY THROUGH THURSDAY...SCT SHRA/TSRA ARE ANTICIPATED EACH
AFTN/EVE...WITH BRIEF RESTRICTIONS PSBL. MVFR RESTRICTIONS ALSO
PSBL IN EARLY MRNG STRATUS/FOG. OTRW VFR PREVAILS.
THU...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...
SHORT TERM...PVN
LONG TERM...RRM
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
350 PM EDT SUN JUL 7 2013
.SYNOPSIS...
THE BERMUDA HIGH WILL CONTINUE TO AFFECT THE LOCAL WEATHER THRU
OUT THE UPCOMING WEEK...HOWEVER ITS POSITIONING WILL SLIDE
SLIGHTLY FURTHER OFFSHORE DURING THE WEEK. THIS WILL ALLOW A COLD
FRONT TO SLOWLY APPROACH FROM THE NORTHWEST BY THE NEXT UPCOMING
WEEKEND. TYPICAL SUMMERTIME WEATHER WITH DAILY AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS WILL OCCUR EACH DAY...INCREASING
IN COVERAGE AS WE APPROACH NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SUNDAY...HIGH PRESSURE RIDGING INTO COASTAL CAROLINAS
FROM THE ATLANTIC WILL SHIFT SLIGHTLY EAST THROUGH TODAY. THIS
WILL ALLOW THE WINDS TO SHIFT TO MORE OF A SOUTH DIRECTION INLAND
WITH MORE OF A SOUTHEAST FLOW ALONG THE COAST...ENHANCED WITH AFTN
SEA BREEZE. STILL SEEING PLENTY OF DRY AIR THROUGH THE MID TO
UPPER LEVELS THROUGH TODAY WITH MOISTURE CONFINED TO LOW LEVELS
BELOW 5K FT. FLOW HAS VEERED SLIGHTLY THROUGH THE LOW LEVELS
COMING AROUND TO SOUTHWEST ABOVE THE SURFACE UP THROUGH H85. THIS
HAS KEPT BEST CONVERGENCE AROUND THE RIDGE CLOSER TO THE COAST
WHICH IN TURN HAS KEPT CLOUDS AND SHOWERS FROM PUSHING WELL
INLAND. CONTINUE TO EXPECT GOOD DEAL OF SUNSHINE ACROSS MUCH OF
THE AREA WITH ONLY ISOLATED SHWRS/TSTMS MAINLY ALONG SEA BREEZE
BOUNDARY AND FURTHER INLAND ASSOCIATED WITH CONVERGENCE AROUND
HIGH. HRRR SHOWING QUITE A FEW SHOWERS OVER SC THIS
AFTERNOON...REMAINING MAINLY WEST OF I95. DRIER AIR WILL CONTINUE
TO PUSH INLAND WITH PROGRESSION OF SEA BREEZE. MODELS SHOW PCP
WATER VALUES UP CLOSE TO 1.7 INCHES INLAND THIS AFTN DROPPING DOWN
TO 1.2 INCHES BY LATE THIS EVENING. THEREFORE CLOUDS AND ISOLATED
SHOWERS THAT DEVELOP ALONG THIS BOUNDARY AS IT PROGRESSES
INLAND...WILL LEAVE MOST OF THE COAST CLEAR BY THIS AFTERNOON AND
INLAND AREAS BY LATE THIS EVENING.
TEMPS BETWEEN 85 AND 90 MOST PLACES WILL DROP SLOWLY THROUGH THE
EVENING. EXPECT OVERNIGHT LOWS TO BE BETWEEN 70 AN 75 WITH
SLIGHTLY WARMER TEMPS RIGHT ALONG THE COAST WHERE WARMER OCEAN
WATERS WILL KEEP THEM HIGHER. MOISTURE PROFILES SHOW SOME UPPER
LEVEL MOISTURE INCREASING TONIGHT AS THE UPPER TROUGH CURRENTLY
OVER SOUTHERN ILLINOIS LIFTS NORTHEAST PRODUCING A MORE NW FLOW IN
THE UPPER ATMOSPHERE. THIS WILL PRODUCE SOME CIRRUS BY MORNING BUT
OVERALL EXPECT MAINLY CLEAR SKIES. HAVE INCLUDED MENTION OF PATCHY
FOG BUT LEFT OUT ANY SHOWERS...ALTHOUGH CAN NOT RULE OUT AN
ISOLATED SHOWER OR TWO MOVING ON SHORE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...THE WESTERN ATLANTIC RIDGING BOTH SFC AND
ALOFT AND HAVING PROVIDED THE TROPICAL WX TYPE CONDITIONS DURING
THIS EXTENDED JULY 4TH WEEKEND...WILL WEAKEN ACROSS THE AREA
MONDAY INTO TUESDAY. THIS A RESULT OF THE SLIGHT PROGRESSION OF WX
FEATURES BOTH ALOFT AND AT THE SFC. THE UPPER RIDGE AXIS AND THE
CENTER OF THE ASSOCIATED WESTERN ATLANTIC SFC HIGH...AKA BERMUDA
HIGH...IS PROGGED BY THE MODELS TO SLIDE FURTHER OFFSHORE FROM
THE CAROLINA COASTS. THE ORIENTED LOWER TO MID MISSISSIPPI AND
OHIO RIVER UPPER TROF IS PROGGED TO FLATTEN SOME AS THE MAIN VORT
FINALLY PROGRESSES NE TO E...STAYING WELL NORTH OF THE FA DURING
THIS SHORT TERM PERIOD. WHAT FINALLY ENDS UP IS A LOW AMPLITUDE
UPPER TROUGHINESS ALONG THE SPINE OF THE APPALACHIANS FROM VA
SOUTHWESTWARD...AND LEE SIDE SFC TROFFINESS ACROSS THE CAROLINAS.
THE SFC RIDGE AXIS EXTENDING SW-W FROM THE OFFSHORE BERMUDA HIGH
WILL EVENTUALLY DROP SOUTH OF THE ILM CWA. THE TRUE ATLANTIC
TROPICAL ATM REGIME OF THE PAST SEVERAL DAYS WILL FINALLY COME
PARTIALLY TO AN END. WITH THE ADDITION OF CONVECTIVE FOCUS
MECHANISMS BESIDES THE SEA BREEZE FOR MON AND TUE AS WELL AS
BETTER INSTABILITY...POPS WILL SLOWLY INCREASE BUT REMAIN CAPPED
IN THE CHANCE CATEGORY. POPS WILL PEAK DURING THE AFTN/EARLY
EVENING AIDED BY THE DAYS HEATING. THE NOCTURNAL TROPICAL REGIME
TYPE CONVECTION OVER THE ATL WATERS OF THE PAST SEVERAL DAYS WILL
NO LONGER HAVE A STRAIGHT LINE SHOT TO THE IMMEDIATE COAST DURING
PRE-DAWN TUE...AND PRE-DAWN WED. HOWEVER BY PRE-DAWN WED...A SFC
TROF WILL HAVE REACHED THE ATLANTIC WATERS OFF THE SE U.S.
COAST...WHICH IS A REFLECTION FROM AN UPPER LOW THAT TRAVERSES THE
BAHAMAS MON AND PARTIALLY ACROSS FLORIDA TUE. MOISTURE ASSOCIATED
WITH THIS FEATURE COULD REACH THE ATL WATERS AND PUSH PARTIALLY ON
SHORE LATE ON THE PRE-DAWN WED HOURS. THIS WILL NEED TO BE
MONITORED. FOR MAX TEMPS MON AND TUE...GUIDANCE REMAINS RATHER
CLUSTERED WITH MID 80S ALONG THE IMMEDIATE COAST...UPPER 80S TO
AROUND 90 FROM THE COAST TO THE I-95 CORRIDOR...AND LOWER 90S WEST
OF THE I-95 CORRIDOR. FOR MIN TEMPS BOTH MORNINGS...A 70 TO 75
RANGE...THE EXCEPTION WILL BE THE IMMEDIATE COAST WHERE MID 70S TO
RULE BOTH DAYS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 300 PM SUNDAY...WHILE THE BEGINNING OF THE PERIOD WILL
CONTINUE WITH WARM SUMMER CONDITIONS AND ONLY ISOLATED
CONVECTION...A PATTERN REGIME CHANGE WILL OCCUR BY THE END OF THE
WEEK...AND A RENEWED WET PERIOD IS BECOMING MORE LIKELY FOR THE WKND.
BERMUDA HIGH AT THE SURFACE AND FLAT RIDGING ALOFT WILL CREATE ONE
LAST DAY OF TEMPS AT TO ABOVE CLIMO WITH A LOT OF SUNSHINE AND
LITTLE CONVECTION. THEREAFTER...UPPER TROUGHING BEGINS TO BUILD DOWN
FROM THE NORTHWEST AND ACROSS THE EASTERN CONUS. WHILE THE COLD
FRONT ASSOCIATED WITH THIS UPPER TROUGH WILL LIKELY GET HELD UP AND
WASH OUT JUST NORTH OF THE LOCAL AREA...DECREASING HEIGHTS ALOFT
WILL STEEPEN LAPSE RATES...LEADING TO INCREASING CONVECTIVE
POTENTIAL. AT THE SAME TIME...TROPICAL WAVE WHICH HAS BEEN PROGGED
TO MOVE BENEATH THE BERMUDA HIGH AND INTO FLORIDA WILL FEED SOME OF
ITS MOISTURE INTO THE CAROLINAS BEGINNING FRIDAY. THIS ENHANCED
MOISTURE...PWATS RISING TO OVER 2 INCHES...COMBINED WITH THE STEEPER
LR`S IN THE MID-LEVELS WILL SUPPORT EVEN MORE SIGNIFICANT CONVECTION
ON FRIDAY. DO NOT ANTICIPATE A SEVERE THREAT ATTM...BUT HEAVY RAIN
WILL BE POSSIBLE. MAX TEMPS WILL REMAIN AROUND CLIMO THROUGH THE END
OF THE WEEK...WITH LOWS HOVERING A FEW DEGREES ABOVE.
WEATHER COULD DETERIORATE MORE CONSIDERABLY FOR NEXT WEEKEND. 5H
TROUGH CLOSES OFF IN RESPONSE TO STRONG AMPLIFICATION OF THE
FLOW...AND BLOCKING RIDGE ACROSS THE WESTERN ATLANTIC. THIS FORCES
THE CLOSED LOW TO RETROGRADE TO THE WEST...WITH DEEP SOUTHERLY FLOW
ONCE AGAIN DEVELOPING ACROSS THE SOUTHEAST. IN A PATTERN EERILY
REMINISCENT OF THE END OF JUNE...CLOSED LOW ACROSS THE TN VLY WITH
BLOCKING HIGH OVER THE OCEAN WILL DRIVE TROPICAL MOISTURE INTO THE
REGION AND A WET PERIOD AGAIN LOOKS TO BE IN STORE. FORTUNATELY...AT
LEAST FOR D6/D7...IT DOES NOT LOOK QUITE AS ROBUST AS THE PATTERN WE
SAW TO CLOSE OUT JUNE...BUT AN EXTENDED PERIOD OF UNSETTLED
WEATHER LOOKS LIKELY FOR NEXT WKND.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
AS OF 18Z...HIGH PRESSURE OFFSHORE WILL CONTINUE TO GIVE US SOUTH
SOUTHEAST FLOW THROUGH THE PERIOD. NO FOG EXPECTED WITH WINDS AT
THE BOUNDARY LAYER 15+ KTS. MONDAY...MODELS INDICATE HIGH LEVEL
MOISTURE RETURNING...WITH BROKEN CIRRUS EXPECTED ALL DAY. WINDS WILL
BE A BIT MORE SOUTHWESTERLY.
EXTENDED OUTLOOK...EARLY MORNING IFR/MVFR CIGS/VSBYS POSSIBLE
THROUGH THE EXTENDED PERIOD. INCREASING CHANCES FOR SHOWERS AND
THUNDERSTORMS THURSDAY AND FRIDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SUNDAY...SOUTHERLY RETURN FLOW 10 TO 15 KTS WILL
PERSIST ACROSS THE WATERS AROUND THE PERIPHERY OF BERMUDA HIGH
PRESSURE. THE WINDS WILL ACTUALLY VEER EVER SO SLIGHTLY FROM S-SE
TO S-SW BY MORNING REMAINING AROUND 10 KTS FOR THE MOST PART. AN 8
SECOND SE SWELL WILL CONTINUE TO MIX WITH LOCALLY GENERATED WIND
WAVES TO PRODUCE TOTAL SEAS OF 2 TO 3 FT.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...THE WESTERN ATLANTIC HIGH...AKA BERMUDA
HIGH...WILL REMAIN THE PRIMARY INFLUENCE OF THE WINDS ACROSS THE
LOCAL WATERS. THE DEVELOPMENT OF THE LEE-SIDE TROF ACROSS THE
WESTERN AND CENTRAL CAROLINAS...AND THE SFC RIDGE AXIS THAT
EXTENDS SW-W FROM THE CENTER OF THE BERMUDA HIGH OFFSHORE...IS
PROGGED TO DROP SOUTH OF THE LOCAL WATERS THIS TIME PERIOD.
THEREFORE...A SW WIND DIRECTION WILL EVENTUALLY BECOME THE
DOMINANT WIND DIRECTION. THE DAILY SEA BREEZE WILL TEMPORARILY
BACK WINDS TO A MORE SOUTHERLY DIRECTION EACH AFTN/EVENING. WITH
THE CENTER OF THE HIGH FURTHER AWAY AND OFFSHORE FROM THE ILM
WATERS...THE SFC PG WILL SLIGHTLY TIGHTEN. BASICALLY LOOKING AT
WIND SPEEDS IN THE 10 TO 15 KT RANGE...WITH THE SEA BREEZE ADDING
5 KT OF SPEED NEARSHORE EACH AFTN AND EVENING...THUS REACHING 15
TO POSSIBLY 20 KT. SIGNIFICANT SEAS WILL HOVER AROUND THE 3 FOOT
HEIGHT THRU-OUT THE SHORT TERM.
THERE WILL BE LESS OF AN INFLUENCE FROM THE 6 TO 8 SECOND PERIOD
SE SWELL DUE TO FETCH LIMITATIONS...BUT AN INCREASED INFLUENCE
FROM THE 3 TO 5 SECOND PERIOD WIND DRIVEN WAVES. THIS WILL FINALLY
BEGIN TO LOWER THE RIP CURRENT RISK...RELATIVELY SPEAKING. IN
ADDITION...BOATERS NAVIGATING TO AND FROM THE ATL THRU AREA INLETS
WILL ALSO IMPROVE...SOME ESPECIALLY WHEN TRAVERSING THESE WATERS
DURING AN OUT-GOING TIDE.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...BERMUDA HIGH OFFSHORE PERSISTS DURING THE
EXTENDED...KEEPING SW WINDS ONGOING ACROSS THE WATERS. WHILE THE
GRADIENT ON THE WESTERN SIDE OF THIS RIDGE REMAINS RELATIVELY
WEAK...IT DOES SLOWLY STRENGTHEN LATE IN THE WEEK IN RESPONSE TO A
COLD FRONT DRIFTING SLOWLY TOWARDS THE AREA. WHILE THIS FRONT WILL
LIKELY NOT MAKE IT TO THE WATERS...AND INSTEAD WASH OUT ACROSS THE
CENTRAL CAROLINAS FRIDAY...THE PINCHING GRADIENT WILL HELP WINDS
INCREASE FROM 10-15 KTS WEDNESDAY TO 15-20 KTS THURSDAY AND
FRIDAY. THE SE SWELL WILL SLOWLY DECAY THROUGH THE PERIOD...BUT SW
WIND WAVES WILL GRADUALLY INCREASE IN AMPLITUDE. SEAS WILL BUILD
FROM 2-3 FT WEDNESDAY...TO AS MUCH AS 4-5 FT LATE THURSDAY INTO
FRIDAY...AND A SCEC MAY BE REQUIRED FOR A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR SCZ054.
NC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ106-
108-110.
MARINE...NONE.
&&
$$
SYNOPSIS...DCH
NEAR TERM...RGZ
SHORT TERM...DCH
LONG TERM...JDW
AVIATION...RGZ/DL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A WEAKENING UPPER LEVEL LOW WILL PROGRESS EAST ACROSS THE MID-
ATLANTIC TONIGHT. CYCLONIC FLOW ALOFT WILL PREVAIL OVER THE EASTERN
UNITED STATES THROUGH MID WEEK...WITH AN UNSEASONABLY DEEP UPPER
LEVEL TROUGH DIGGING SOUTHEAST IN THE MID-ATLANTIC BY FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 PM SUNDAY...
SOME VERY LIGHT SHOWERS REMAIN IN THE NORTHEAST PIEDMONT...BUT THE
STRONGER STORMS AND BETTER COVERAGE REMAINS JUST WEST OF THE TRIAD.
AS WITH YESTERDAY...THE HRRR HIGH RES CAM IS DOING THE BEST AT
SIMULATING THE CURRENT SHOWER ACTIVITY...ALTHOUGH THE TIMING MAY BE
A BIT OFF. HIGH PRESSURE REMAINS OFF THE CAROLINA COAST...WITH THE
LOW WEST OF THE APPALACHIANS OVER IL/IN. LOW LEVEL MOISTURE IS
ADVECTING INTO WESTERN NC OFF THE GULF AHEAD OF THE LOW PRESSURE
SYSTEM. AS THE UPPER LEVEL LOW CONTINUES TO MOVE EASTWARD INTO PA
TONIGHT...SMALL AMPLITUDE SHORTWAVES WILL TRACK NORTHEAST ACROSS
WESTERN NC/VA. IN ADDITION TO THE SHORTWAVES...MOISTURE CONVERGENCE
ALONG THE PIEDMONT TROUGH ARE THE LIKELY DRIVING MECHANISMS FOR THE
CONVECTION MOVING INTO THE TRIAD. CURRENT ANALYZED MLCAPE VALUES
RANGE FROM 1500-2000 J/KC ACROSS CENTRAL NC...WITH THE BEST CAPE
DISPLACED FROM THE BEST SHEAR (OVER THE MTNS). BEST CHANCES FOR
SHOWERS/STORMS WILL REMAIN IN THE WEST THROUGH TONIGHT. THERE IS THE
POTENTIAL FOR SOME STORMS TO PRODUCE DAMAGING WINDS THIS AFT/EVE...
MAINLY IN AND AROUND THE TRIAD WHERE THE DCAPE IS ANALYZED AROUND
1000 J/KG AND 0-6 KM SHEAR VALUES AROUND 30 KTS. LOWS TONIGHT
SIMILAR TO PREVIOUS NIGHTS IN THE LOWER 70S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 240 PM SUNDAY...
AS THE UPPER LEVEL LOW MAKES ITS WAY ACROSS PA AND INTO NEW ENGLAND
MONDAY AND MONDAY NIGHT...THE ASSOCIATED TROUGH WILL MOVE INTO
CENTRAL NC...THUS DAMPENING THE HIGH AND PUSHING THE RIDGE AXIS
SOUTH AND EAST. THE MAIN SHOWER ACTIVITY WILL SHIFT SLOWLY EASTWARD
THROUGH THE DAY AND INTO THE EVENING MONDAY AS ADDITIONAL SHORTWAVE
DISTURBANCES MOVE OVER THE AREA. HIGHEST PRECIP CHANCES COINCIDE
WITH PEAK HEATING...AND WILL DECREASE SUBSTANTIALLY AFTER SUNSET.
HIGH TEMPS WILL BE SIMILAR TO TODAY...MID 80S NW INCREASING TO NEAR
90 IN THE EAST. OVERNIGHT LOWS WILL AGAIN BE SIMILAR TO PREVIOUS
NIGHTS...MAINLY IN THE LOW 70S.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 230 PM SUNDAY...
FOR TUESDAY/TUESDAY NIGHT: VERY WEAK MID LEVEL TROUGH AXIS HOLDS
OVER THE EAST COAST WHILE A SUBTLE SURFACE TROUGH HOLDS OVER THE NC
PIEDMONT. ABOVE-NORMAL DEEP MOISTURE PERSISTS ESPECIALLY SOUTH AND
EAST OF THE TROUGH WITH PW VALUES RANGING FROM 1.7-2.0 INCHES FROM
NW TO SE OVER CENTRAL NC. THE WEAK WIND FIELD (PROJECTED WINDS NO
GREATER THAN 15 KTS BELOW 400 MB) THROUGHOUT THE MOIST COLUMN
COMBINED WITH DAYTIME DESTABILIZATION (MLCAPE PEAKING AT 1200-2000
J/KG) SUGGEST SCATTERED STORMS DEVELOPING IN THE AFTERNOON WITH SLOW
MOVEMENT AND THE POTENTIAL TO DUMP SOME HEAVY RAIN... GIVEN THE
LCL-TO-0C LAYER DEPTH APPROACHING 3.8-4 KM. THE GFS/NAM/ECMWF
GENERALLY FAVOR BETTER COVERAGE OVER THE SOUTHEAST CWA IN
CONJUNCTION WITH THE GREATEST MOISTURE AND INSTABILITY... SO WILL
EDGE POPS HIGHER THERE THAN IN THE REST OF THE CWA. SHOWERS/STORMS
SHOULD FOLLOW A TYPICAL DIURNAL PATTERN OF TAPERING DOWN AFTER
NIGHTFALL... ALTHOUGH WITH ANOMALOUSLY HIGH MOISTURE CONTINUING TO
POOL OVER CENTRAL NC... A FEW MEANDERING SHOWERS AND ISOLATED STORMS
MAY PERSIST OVERNIGHT. HIGHS 86-90. LOWS 70-73.
FOR WEDNESDAY/WEDNESDAY NIGHT: THIS LOOKS TO BE THE TIME FRAME WITH
A RELATIVE MINIMUM IN RAIN CHANCES... BUT CERTAINLY NOT ZERO
CONSIDERING THE STILL-HIGH PW VALUES NEAR 2.0 INCHES. THE WESTERLIES
TAKE A DIP INTO THE GREAT LAKES AS THE TROUGH BEGINS TO DIG TO OUR
NORTHWEST... RESULTING A SLIGHT DOWNSTREAM REBOUNDING IN HEIGHTS
OVER NC. GFS FORECAST SOUNDINGS SHOW A PERIOD OF MID LEVEL DRYING
BETWEEN 800 AND 500 MB MAINLY IN THE EASTERN CWA... WHERE BOTH THE
GFS AND ECMWF SHOW FAIRLY LOW QPF. WILL LEAVE IN CHANCE POPS...
SKEWED HIGHER IN THE TRIAD AND LOWER IN THE SOUTHEAST... FOCUSED ON
THE AFTERNOON/EVENING. HIGHS 87-91 AS THICKNESSES STAY NEAR
CLIMATOLOGY. THE DEEPENING MID LEVEL TROUGH TO OUR WEST RESULTS IN
AN UPTICK IN MID LEVEL WINDS OVER NW NC WEDNESDAY NIGHT... AND WITH
MOISTURE REMAINING HIGH OR EVEN INCREASING A BIT OVER OUR NW CWA
OVERNIGHT... WILL HOLD ONTO CHANCE POPS HERE WITH JUST A SLIGHT
CHANCE ELSEWHERE. LOWS 70-74.
FOR THURSDAY THROUGH SUNDAY: CONFIDENCE IS IMPROVING THAT THIS WILL
BE A FAIRLY WET PERIOD. THE LONGWAVE TROUGH DIGS FURTHER THROUGH THE
EASTERN GREAT LAKES AND OH VALLEY ON THURSDAY AS THE SURFACE COLD
FRONT MOVES IN FROM THE NW... AND THE INCREASING DYNAMICS AND DEEP
MOISTURE FLUX OVER NC WILL BRING INCREASING SHOWER/STORM COVERAGE
FROM NW TO SE AS WE HEAD THROUGH THURSDAY AFTERNOON/NIGHT. THE
MODELS CLOSE OFF A LOW TO OUR NORTHWEST... OVER WV/ERN KY/ERN TN...
ON FRIDAY BEFORE DROPPING IT DOWN TO NRN GA/AL/MS OVER THE WEEKEND.
SUCH A CLOSED LOW THAT FAR SOUTH IS HIGHLY UNUSUAL FOR THIS TIME OF
YEAR (GEFS FORECAST 500 MB HEIGHTS OVER 2 STANDARD DEVIATIONS BELOW
NORMAL OVER THE SOUTHEAST STATES)... SO IT IS SURPRISING HOW GOOD
THE AGREEMENT IS BETWEEN THE OP GFS (12Z/07) AND ECMWF (00Z/07).
WITH THE LOSS OF EASTWARD PUSH... THE SURFACE FRONT IS LIKELY TO
STALL OUT OVER CENTRAL NC... AND WITH A STRENGTHENING AND DEEPENING
SOUTHERLY FLOW ALLOWING 2.0+ INCH PW VALUES TO STREAK OVER CENTRAL
NC FROM THURSDAY NIGHT THROUGH AT LEAST SATURDAY... WITH SOME DRYING
POSSIBLE SUNDAY AS A LARGE AND STRONG MID LEVEL CYCLONE BUILDS FROM
OFF THE CANADIAN MARITIMES SOUTHWESTWARD INTO NC. WILL KEEP HIGH
RAIN CHANCES FOR THURSDAY NIGHT THROUGH SATURDAY... A BIT HIGHER IN
THE AFTERNOON/EVENING BUT NOT YIELDING MUCH AT NIGHT... DROPPING
BACK TOWARD CLIMATOLOGICAL POPS ON SUNDAY. EXPECT QUITE A BIT OF
CLOUDINESS THROUGH THIS PERIOD WITH HUMID CONDITIONS REDUCING THE
DIURNAL TEMP RANGE. LOWS AROUND 70-75 AND HIGHS IN THE LOW-MID 80S.
-GIH
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
AS OF 125 PM SUNDAY...
24-HR TAF PERIOD:
CIGS HAVE BEEN BORDERLINE VFR/MVFR ALL DAY...BOUNCING BACK AND FORTH
BETWEEN THE TWO...AND WILL LIKELY CONTINUE TO BE SO THROUGH MONDAY
MORNING. LIGHT SHOWERS ARE OCCURRING AROUND KRDU...WITH HEAVIER
SHOWERS AND POSSIBLE THUNDER MOVING INTO THE TRIAD (KINT AND KGSO)
THIS AFTERNOON AND INTO THE OVERNIGHT HOURS. BEST CHANCE FOR LOW-END
MVFR CIGS AT KINT AND KGSO DURING THE PRE-DAWN HOURS MONDAY...WITH
THE POTENTIAL FOR A PERIOD OF BORDERLINE VFR/MVFR CIGS ELSEWHERE...
ALTHOUGH CONFIDENCE IS LOW GIVEN THE DIFFERENCES IN MODEL GUIDANCE
AT THIS TIME. THERE IS THE CHANCE FOR SHOWERS TO REDEVELOP ACROSS
THE AREA MONDAY AFTERNOON/EVENING...BUT WILL LEAVE MENTION OUT OF
TAFS FOR NOW. -KC
LOOKING AHEAD:
AVIATION CONDITIONS THROUGH MID/LATE WEEK WILL BE CHARACTERIZED BY
AN ABOVE NORMAL CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY
(PRIMARILY AFTERNOON AND EVENING HOURS) IN ASSOCIATION WITH CYCLONIC
FLOW ALOFT AND AN ABOVE NORMAL CHANCE FOR MVFR/IFR STRATUS OR FOG
EACH MORNING (PRIMARILY 07-13Z) IN ASSOCIATION WITH A PERSISTENT
MOIST SOUTHERLY RETURN FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...KC
SHORT TERM...KC
LONG TERM...HARTFIELD
AVIATION...KC/VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
230 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A WEAKENING UPPER LEVEL LOW WILL PROGRESS EAST ACROSS THE MID-
ATLANTIC TONIGHT. CYCLONIC FLOW ALOFT WILL PREVAIL OVER THE EASTERN
UNITED STATES THROUGH MID WEEK...WITH AN UNSEASONABLY DEEP UPPER
LEVEL TROUGH DIGGING SOUTHEAST IN THE MID-ATLANTIC BY FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1025 AM SUNDAY...
SOME VERY LIGHT SHOWERS HAVE DEVELOPED OVER THE SOUTHERN PIEDMONT
AND SANDHILLS THIS MORNING. AS WITH YESTERDAY...THE HRRR HIGH RES
CAM IS DOING A GOOD JOB SIMULATING THE CURRENT SHOWER ACTIVITY. THE
LATEST RUN OF THE HRRR SHOWS AN INCREASE IN SHOWER COVERAGE...MAINLY
IN THE NORTHEAST PIEDMONT AND SANDHILLS THROUGH THIS AFTERNOON...
WITH THE MORE WIDESPREAD CONVECTION MOVING INTO THE NORTHWEST
PIEDMONT LATE THIS AFT/EVE. 12Z UPPER AIR ANALYSES SHOW THE LOW WEST
OF THE APPALACHIANS OVER IL/IN...WITH HIGH PRESSURE OFF THE CAROLINA
COAST. WHILE CENTRAL NC IS RELATIVELY DRY...LOW LEVEL MOISTURE IS
ADVECTING IN OFF THE GULF AHEAD OF THE LOW PRESSURE SYSTEM. AS THE
UPPER LEVEL LOW MOVES EASTWARD TODAY SO WILL THE LOW/MID LEVEL
MOISTURE AND SHOWERS/STORMS...CURRENTLY OVER THE MOUNTAINS. -KC
PRECIPITATION CHANCES:
SW FLOW ALOFT WILL STRENGTHEN FROM THE WEST TODAY...WITH AN
INCREASING POTENTIAL FOR SMALL AMPLITUDE SHORTWAVES TRACKING
NORTHEAST ACROSS WESTERN NC/VA THIS AFT/EVE...FOLLOWED BY ADDITIONAL
DPVA WITHIN INCREASINGLY CYCLONIC FLOW ALOFT AS THE UPPER LEVEL LOW
TRACKS INTO WESTERN PA BETWEEN 00-06Z TONIGHT. SHALLOW CONVERGENCE
IN VICINITY OF A DEVELOPING PIEDMONT SFC TROUGH ASSOCIATED WITH
SUBTLE HEIGHT FALLS IN ADVANCE OF THE UPPER LEVEL WAVE APPROACHING
THE REGION THIS AFT/EVE WILL SERVE AS A POTENTIAL FOCUS FOR DIURNAL
CONVECTION THIS AFTERNOON...FOLLOWED BY SOMEWHAT DEEPER CONVERGENCE
TONIGHT AS THE LOW-LEVEL TROUGH SHARPENS IN RESPONSE TO STRONGER
HEIGHT FALLS /CYCLONIC FLOW ALOFT/ OVER THE MID-ATLANTIC. SEASONAL
BOUNDARY LAYER MOISTURE/DESTABILIZATION CAN BE EXPECTED AGAIN THIS
AFTERNOON...WITH MLCAPE VALUES GENERALLY IN THE 1000-2000 J/KG RANGE
ACROSS CENTRAL NC...THOUGH A WEST-EAST MID-LEVEL MOISTURE GRADIENT
WILL PERSIST WITH DEEPER MOISTURE ACROSS THE FOOTHILLS/WESTERN
PIEDMONT AND A DRIER AIRMASS ALOFT IN THE COASTAL PLAIN. WITH THE
ABOVE IN MIND...EXPECT THE BEST CHANCE FOR CONVECTION THIS AFTERNOON
AND EARLY EVENING WEST OF THE HWY 1 CORRIDOR IN VICINITY OF THE
PIEDMONT SFC TROUGH AND IN CLOSER PROXIMITY TO SMALL AMPLITUDE
SHORTWAVES/DEEPER MOISTURE IN STRENGTHENING SW FLOW ALOFT. WILL
INDICATE PRECIP CHANCES RANGING FROM 20% EAST OF I-95 TO 50-60% IN
THE FAR W/NW PIEDMONT. CONVECTION SHOULD PERSIST INTO TONIGHT ACROSS
THE NORTHERN AND WESTERN PIEDMONT AS BETTER DPVA /STRONGER CYCLONIC
FLOW ALOFT/ PROGRESSES INTO THE MID-ATLANTIC.
TEMPERATURES:
EXPECT HIGHS TODAY SIMILAR TO PREVIOUS DAYS WITH VERY SIMILAR
REASONING...THOUGH PERHAPS SLIGHTLY WARMER GIVEN A MORE
SOUTHWESTERLY LOW-LEVEL FLOW...ESP. ALONG AND EAST OF THE HWY 1
CORRIDOR...WITH HIGHS RANGING FROM THE MID 80S FAR NW PIEDMONT TO
UPPER 80S AND LOWER 90S ELSEWHERE. LOWS TONIGHT SIMILAR TO PREVIOUS
NIGHTS IN THE LOWER 70S.
SEVERE THREAT:
GIVEN DEEP LAYER SHEAR IN THE 25-35 KT RANGE ACROSS THE N/NW
PIEDMONT IN THE PRESENCE OF MODERATE INSTABILITY (1000-2000 J/KG
MLCAPE) AND DCAPE VALUES PROGGED AS HIGH AS 1000-1500 J/KG THIS AFT
AND EARLY EVE...ANTICIPATE A POTENTIAL FOR DAMAGING WINDS...
PRIMARILY WEST AND NW OF THE TRIANGLE. -VINCENT
&&
.SHORT TERM /MONDAY/...
AS OF 325 AM SUNDAY...
ALTHOUGH THE AFOREMENTIONED UPPER LEVEL WAVE WILL TRACK EAST THROUGH
THE MID-ATLANTIC EARLY MONDAY MORNING...CYCLONIC FLOW ALOFT AND
LOW-LEVEL TROUGHING WILL PERSIST ACROSS THE AREA MONDAY
AFT/EVE...WITH ADDITIONAL SHORTWAVE ENERGY ANTICIPATED TO DIG
SOUTHEAST INTO NC/VA IN VICINITY OF PEAK HEATING. AS A RESULT...
EXPECT ABOVE NORMAL CHANCES FOR CONVECTION...PRIMARILY DURING THE
AFTERNOON AND EVENING HOURS...WITH HIGHS SIMILAR TO PREVIOUS DAYS...
IN THE MID/UPPER 80S TO NEAR 90F. -VINCENT
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 230 PM SUNDAY...
FOR TUESDAY/TUESDAY NIGHT: VERY WEAK MID LEVEL TROUGH AXIS HOLDS
OVER THE EAST COAST WHILE A SUBTLE SURFACE TROUGH HOLDS OVER THE NC
PIEDMONT. ABOVE-NORMAL DEEP MOISTURE PERSISTS ESPECIALLY SOUTH AND
EAST OF THE TROUGH WITH PW VALUES RANGING FROM 1.7-2.0 INCHES FROM
NW TO SE OVER CENTRAL NC. THE WEAK WIND FIELD (PROJECTED WINDS NO
GREATER THAN 15 KTS BELOW 400 MB) THROUGHOUT THE MOIST COLUMN
COMBINED WITH DAYTIME DESTABILIZATION (MLCAPE PEAKING AT 1200-2000
J/KG) SUGGEST SCATTERED STORMS DEVELOPING IN THE AFTERNOON WITH SLOW
MOVEMENT AND THE POTENTIAL TO DUMP SOME HEAVY RAIN... GIVEN THE
LCL-TO-0C LAYER DEPTH APPROACHING 3.8-4 KM. THE GFS/NAM/ECMWF
GENERALLY FAVOR BETTER COVERAGE OVER THE SOUTHEAST CWA IN
CONJUNCTION WITH THE GREATEST MOISTURE AND INSTABILITY... SO WILL
EDGE POPS HIGHER THERE THAN IN THE REST OF THE CWA. SHOWERS/STORMS
SHOULD FOLLOW A TYPICAL DIURNAL PATTERN OF TAPERING DOWN AFTER
NIGHTFALL... ALTHOUGH WITH ANOMALOUSLY HIGH MOISTURE CONTINUING TO
POOL OVER CENTRAL NC... A FEW MEANDERING SHOWERS AND ISOLATED STORMS
MAY PERSIST OVERNIGHT. HIGHS 86-90. LOWS 70-73.
FOR WEDNESDAY/WEDNESDAY NIGHT: THIS LOOKS TO BE THE TIME FRAME WITH
A RELATIVE MINIMUM IN RAIN CHANCES... BUT CERTAINLY NOT ZERO
CONSIDERING THE STILL-HIGH PW VALUES NEAR 2.0 INCHES. THE WESTERLIES
TAKE A DIP INTO THE GREAT LAKES AS THE TROUGH BEGINS TO DIG TO OUR
NORTHWEST... RESULTING A SLIGHT DOWNSTREAM REBOUNDING IN HEIGHTS
OVER NC. GFS FORECAST SOUNDINGS SHOW A PERIOD OF MID LEVEL DRYING
BETWEEN 800 AND 500 MB MAINLY IN THE EASTERN CWA... WHERE BOTH THE
GFS AND ECMWF SHOW FAIRLY LOW QPF. WILL LEAVE IN CHANCE POPS...
SKEWED HIGHER IN THE TRIAD AND LOWER IN THE SOUTHEAST... FOCUSED ON
THE AFTERNOON/EVENING. HIGHS 87-91 AS THICKNESSES STAY NEAR
CLIMATOLOGY. THE DEEPENING MID LEVEL TROUGH TO OUR WEST RESULTS IN
AN UPTICK IN MID LEVEL WINDS OVER NW NC WEDNESDAY NIGHT... AND WITH
MOISTURE REMAINING HIGH OR EVEN INCREASING A BIT OVER OUR NW CWA
OVERNIGHT... WILL HOLD ONTO CHANCE POPS HERE WITH JUST A SLIGHT
CHANCE ELSEWHERE. LOWS 70-74.
FOR THURSDAY THROUGH SUNDAY: CONFIDENCE IS IMPROVING THAT THIS WILL
BE A FAIRLY WET PERIOD. THE LONGWAVE TROUGH DIGS FURTHER THROUGH THE
EASTERN GREAT LAKES AND OH VALLEY ON THURSDAY AS THE SURFACE COLD
FRONT MOVES IN FROM THE NW... AND THE INCREASING DYNAMICS AND DEEP
MOISTURE FLUX OVER NC WILL BRING INCREASING SHOWER/STORM COVERAGE
FROM NW TO SE AS WE HEAD THROUGH THURSDAY AFTERNOON/NIGHT. THE
MODELS CLOSE OFF A LOW TO OUR NORTHWEST... OVER WV/ERN KY/ERN TN...
ON FRIDAY BEFORE DROPPING IT DOWN TO NRN GA/AL/MS OVER THE WEEKEND.
SUCH A CLOSED LOW THAT FAR SOUTH IS HIGHLY UNUSUAL FOR THIS TIME OF
YEAR (GEFS FORECAST 500 MB HEIGHTS OVER 2 STANDARD DEVIATIONS BELOW
NORMAL OVER THE SOUTHEAST STATES)... SO IT IS SURPRISING HOW GOOD
THE AGREEMENT IS BETWEEN THE OP GFS (12Z/07) AND ECMWF (00Z/07).
WITH THE LOSS OF EASTWARD PUSH... THE SURFACE FRONT IS LIKELY TO
STALL OUT OVER CENTRAL NC... AND WITH A STRENGTHENING AND DEEPENING
SOUTHERLY FLOW ALLOWING 2.0+ INCH PW VALUES TO STREAK OVER CENTRAL
NC FROM THURSDAY NIGHT THROUGH AT LEAST SATURDAY... WITH SOME DRYING
POSSIBLE SUNDAY AS A LARGE AND STRONG MID LEVEL CYCLONE BUILDS FROM
OFF THE CANADIAN MARITIMES SOUTHWESTWARD INTO NC. WILL KEEP HIGH
RAIN CHANCES FOR THURSDAY NIGHT THROUGH SATURDAY... A BIT HIGHER IN
THE AFTERNOON/EVENING BUT NOT YIELDING MUCH AT NIGHT... DROPPING
BACK TOWARD CLIMATOLOGICAL POPS ON SUNDAY. EXPECT QUITE A BIT OF
CLOUDINESS THROUGH THIS PERIOD WITH HUMID CONDITIONS REDUCING THE
DIURNAL TEMP RANGE. LOWS AROUND 70-75 AND HIGHS IN THE LOW-MID 80S.
-GIH
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
AS OF 125 PM SUNDAY...
24-HR TAF PERIOD:
CIGS HAVE BEEN BORDERLINE VFR/MVFR ALL DAY...BOUNCING BACK AND FORTH
BETWEEN THE TWO...AND WILL LIKELY CONTINUE TO BE SO THROUGH MONDAY
MORNING. LIGHT SHOWERS ARE OCCURRING AROUND KRDU...WITH HEAVIER
SHOWERS AND POSSIBLE THUNDER MOVING INTO THE TRIAD (KINT AND KGSO)
THIS AFTERNOON AND INTO THE OVERNIGHT HOURS. BEST CHANCE FOR LOW-END
MVFR CIGS AT KINT AND KGSO DURING THE PRE-DAWN HOURS MONDAY...WITH
THE POTENTIAL FOR A PERIOD OF BORDERLINE VFR/MVFR CIGS ELSEWHERE...
ALTHOUGH CONFIDENCE IS LOW GIVEN THE DIFFERENCES IN MODEL GUIDANCE
AT THIS TIME. THERE IS THE CHANCE FOR SHOWERS TO REDEVELOP ACROSS
THE AREA MONDAY AFTERNOON/EVENING...BUT WILL LEAVE MENTION OUT OF
TAFS FOR NOW. -KC
LOOKING AHEAD:
AVIATION CONDITIONS THROUGH MID/LATE WEEK WILL BE CHARACTERIZED BY
AN ABOVE NORMAL CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY
(PRIMARILY AFTERNOON AND EVENING HOURS) IN ASSOCIATION WITH CYCLONIC
FLOW ALOFT AND AN ABOVE NORMAL CHANCE FOR MVFR/IFR STRATUS OR FOG
EACH MORNING (PRIMARILY 07-13Z) IN ASSOCIATION WITH A PERSISTENT
MOIST SOUTHERLY RETURN FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...KC/VINCENT
SHORT TERM...VINCENT
LONG TERM...HARTFIELD
AVIATION...KC/VINCENT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
202 PM EDT SUN JUL 7 2013
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL BRING DEEP BLUE SKIES TO THE EASTERN
CAROLINAS INTO MONDAY. THE BERMUDA HIGH WILL SLIDE FURTHER
OFFSHORE DURING THE WEEK ALLOWING A COLD FRONT TO SLOWLY APPROACH
FROM THE NORTHWEST. TYPICAL SUMMERTIME WEATHER WITH DAILY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL OCCUR
THROUGHOUT THE UPCOMING WEEK. STORM COVERAGE WILL INCREASE LATE IN
THE WEEK AS THE COLD FRONT MOVES CLOSER.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 2 PM SUNDAY...HIGH PRESSURE RIDGING INTO COASTAL CAROLINAS
FROM THE ATLANTIC WILL SHIFT SLIGHTLY EAST THROUGH TODAY. THIS
WILL ALLOW THE WINDS TO SHIFT TO MORE OF A SOUTH DIRECTION INLAND
WITH MORE OF A SOUTHEAST FLOW ALONG THE COAST...ENHANCED WITH AFTN
SEA BREEZE. STILL SEEING PLENTY OF DRY AIR THROUGH THE MID TO
UPPER LEVELS THROUGH TODAY WITH MOISTURE CONFINED TO LOW LEVELS
BELOW 5K FT. FLOW HAS VEERED SLIGHTLY THROUGH THE LOW LEVELS
COMING AROUND TO SOUTHWEST ABOVE THE SURFACE UP THROUGH H85. THIS
HAS KEPT BEST CONVERGENCE AROUND THE RIDGE CLOSER TO THE COAST
WHICH IN TURN HAS KEPT CLOUDS AND SHOWERS FROM PUSHING WELL
INLAND. CONTINUE TO EXPECT GOOD DEAL OF SUNSHINE ACROSS MUCH OF THE
AREA WITH ONLY ISOLATED SHWRS/TSTMS MAINLY ALONG SEA BREEZE
BOUNDARY AND FURTHER INLAND ASSOCIATED WITH CONVERGENCE AROUND
HIGH. HRRR SHOWING QUITE A FEW SHOWERS OVER SC THIS
AFTERNOON...REMAINING MAINLY WEST OF I95. DRIER AIR WILL CONTINUE
TO PUSH INLAND WITH PROGRESSION OF SEA BREEZE. MODELS SHOW PCP
WATER VALUES UP CLOSE TO 1.7 INCHES INLAND THIS AFTN DROPPING DOWN
TO 1.2 INCHES BY LATE THIS EVENING. THEREFORE CLOUDS AND ISOLATED
SHOWERS THAT DEVELOP ALONG THIS BOUNDARY AS IT PROGRESSES
INLAND...WILL LEAVE MOST OF THE COAST CLEAR BY THIS AFTERNOON
AND INLAND AREAS BY LATE THIS EVENING.
TEMPS BETWEEN 85 AND 90 MOST PLACES WILL DROP SLOWLY THROUGH THE
EVENING. EXPECT OVERNIGHT LOWS TO BE BETWEEN 70 AN 75 WITH
SLIGHTLY WARMER TEMPS RIGHT ALONG THE COAST WHERE WARMER OCEAN
WATERS WILL KEEP THEM HIGHER. MOISTURE PROFILES SHOW SOME UPPER LEVEL
MOISTURE INCREASING TONIGHT AS THE UPPER TROUGH CURRENTLY OVER
SOUTHERN ILLINOIS LIFTS NORTHEAST PRODUCING A MORE NW FLOW IN THE
UPPER ATMOSPHERE. THIS WILL PRODUCE SOME CIRRUS BY MORNING BUT OVERALL
EXPECT MAINLY CLEAR SKIES. HAVE INCLUDED MENTION OF PATCHY FOG BUT
LEFT OUT ANY SHOWERS...ALTHOUGH CAN NOT RULE OUT AN ISOLATED
SHOWER OR TWO MOVING ON SHORE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH WILL REMAIN IN PLACE AT THE
SURFACE WHILE ALOFT THE MID LEVEL RIDGE RETREATS EAST. PASSAGE OF
SHORTWAVE TROUGH NORTH OF THE AREA MON INTO MON NIGHT DOES ALLOW
FOR WESTWARD EXPANSION OF 5H RIDGE TUE THOUGH IN A WEAKENED STATE.
WEAKENING MID LEVEL SUBSIDENCE ALONG WITH INCREASING MID LEVEL
MOISTURE LEADS TO INCREASED COVERAGE OF SHOWERS AND THUNDERSTORMS
DURING THE PERIOD. MON DEEPER DRY AIR NEAR THE COAST WILL KEEP
HIGHEST COVERAGE WELL INLAND. AREA OF HIGHER POP EXPANDS EAST ON
TUE AS DEEPER MOISTURE ALSO SPREADS EAST. IMMEDIATE COAST IS
LIKELY TO REMAIN DRY BOTH DAYS BUT MORE COVERAGE IS EXPECTED FOR
TUE.
LATE IN THE PERIOD TROPICAL MOISTURE FROM WEAK WAVE AND 5H LOW
ROUNDING PERIPHERY OF BERMUDA HIGH/5H RIDGE MAY SPREAD OVER THE
SOUTHEAST. THIS COULD RESULT IN AN INCREASE IN NOCTURNAL
CONVECTION ACROSS SC COAST AND NEAR SHORE WATERS TUE NIGHT.
TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE CLIMO. AWAY FROM THE
COAST HIGHS WILL BE IN THE UPPER 80S TO LOWER 90S. LOWS WILL BE IN
THE MID 70S WITH SOME ISOLATED LOWER 70S INLAND.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...PROGRESSIVE MID LEVEL FLOW AND BERMUDA HIGH
WILL MAINTAIN TYPICAL SUMMERTIME CONDITIONS ACROSS THE CAROLINAS
WED AND THU. TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE CLIMO
FOR THE FIRST HALF OF THE PERIOD WITH ISOLATED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. COVERAGE WED WILL BE LIMITED
WITH STORM DEVELOPMENT DEPENDENT ON DIURNAL INSTABILITY AND WEAK
LOW LEVEL CONVERGENCE. THU ACTIVITY SHOULD BE MORE WIDESPREAD AS
MID LEVEL TROUGHING STARTS TO PUSH DOWN THE EAST COAST.
DEVELOPMENT OF MID LEVEL TROUGHING WILL ALSO START ADVECTING
DEEPER MOISTURE OVER THE SOUTHEAST...ENHANCING STORM COVERAGE.
PRECIP CHANCES SIGNIFICANTLY INCREASE DURING THE SECOND HALF OF
THE PERIOD AS EAST COAST MID LEVEL TROUGHING STRENGTHENS...
EVENTUALLY BECOMING CUT OFF LATE IN THE PERIOD. AS 5H TROUGH DIGS
DOWN THE EAST COAST FRI INTO SAT...PUSHING A COLD FRONT INTO THE
REGION..A TROPICAL WAVE MOVES ACROSS CUBA AND INTO FL. TROPICAL
MOISTURE FROM THE WAVE AND DEEP SOUTHERLY FLOW PUSH PRECIPITABLE
WATER VALUES WELL OVER 2 INCHES. DEEP MOISTURE...WEAKLY DIVERGENT
FLOW ALOFT AND STEEPENING LAPSE RATES COMBINED WITH CONVERGENCE
ALONG DISSIPATING COLD FRONT SHOULD LEAD TO AN INCREASE IN
CONVECTION COVERAGE FRI AND SAT. MARGINAL MID LEVEL LAPSE RATES DO
NOT SUGGEST MUCH SEVERE WEATHER POTENTIAL BUT HEAVY RAIN IS LIKELY
TO BE AN ISSUE. INCREASING MOISTURE AND CLOUD COVER FRI/SAT WILL
HOLD HIGHS IN THE MID TO UPPER 80S BUT HELP KEEP LOWS IN THE LOW
TO MID 70S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 18Z...HIGH PRESSURE OFFSHORE WILL CONTINUE TO GIVE US SOUTH
SOUTHEAST FLOW THROUGH THE PERIOD. NO FOG EXPECTED WITH WINDS AT
THE BOUNDARY LAYER 15+ KTS. MONDAY...MODELS INDICATE HIGH LEVEL
MOISTURE RETURNING...WITH BROKEN CIRRUS EXPECTED ALL DAY. WINDS WILL
BE A BIT MORE SOUTHWESTERLY.
EXTENDED OUTLOOK...EARLY MORNING IFR/MVFR CIGS/VSBYS POSSIBLE
THROUGH THE EXTENDED PERIOD. INCREASING CHANCES FOR SHOWERS AND
THUNDERSTORMS THURSDAY AND FRIDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2 PM SUNDAY...SOUTHERLY RETURN FLOW 10 TO 15 KTS WILL
PERSIST ACROSS THE WATERS AROUND THE PERIPHERY OF BERMUDA HIGH
PRESSURE. THE WINDS WILL ACTUALLY VEER EVER SO SLIGHTLY FROM S-SE
TO S-SW BY MORNING REMAINING AROUND 10 KTS FOR THE MOST PART. AN 8
SECOND SE SWELL WILL CONTINUE TO MIX WITH LOCALLY GENERATED WIND
WAVES TO PRODUCE TOTAL SEAS OF 2 TO 3 FT.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH WILL MAINTAIN SOUTH TO SOUTHWEST
FLOW OVER THE WATERS THROUGH THE PERIOD. LITTLE CHANGE TO SURFACE
PRESSURE GRADIENT WILL KEEP SPEEDS IN THE 10 TO 15 KT RANGE. SEAS
WILL RUN 2 TO 3 FT A MIX OF SOUTHEAST SWELL AND SOUTHERLY WIND WAVE.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...DOMINANT SURFACE FEATURE THROUGH THE PERIOD
CONTINUES TO BE BERMUDA HIGH BUT GRADIENT WILL TIGHTEN UP FOR THE
SECOND HALF OF THE PERIOD. ON WED SPEEDS WILL REMAIN 10 TO 15 KT
WITH WEAK GRADIENT IN PLACE. COLD FRONT SLOWLY APPROACHING FROM THE
NORTHWEST LATER THU AND THU NIGHT WILL RESULT IN A MORE DEFINED
GRADIENT WITH WIND SPEEDS EXCEEDING 15 KT AT TIMES. INCREASE IN
SPEEDS WILL BUILD SEAS FROM 2 TO 3 FT WED TO 3 TO 5 FT BY THE END
OF THE PERIOD. SEAS WILL STILL BE COMPRISED OF SOUTHEAST SWELL AND
SOUTHERLY WIND WAVE BUT THE WIND WAVE WILL BECOME THE DOMINANT
COMPONENT LATER THU.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR SCZ054.
NC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ106-
108-110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...DL/RGZ
AREA FORECAST DISCUSSION
NWS RALEIGH NC
129 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A WEAKENING UPPER LEVEL LOW WILL PROGRESS EAST ACROSS THE MID-
ATLANTIC TONIGHT. CYCLONIC FLOW ALOFT WILL PREVAIL OVER THE EASTERN
UNITED STATES THROUGH MID WEEK...WITH AN UNSEASONABLY DEEP UPPER
LEVEL TROUGH DIGGING SOUTHEAST IN THE MID-ATLANTIC BY FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1025 AM SUNDAY...
SOME VERY LIGHT SHOWERS HAVE DEVELOPED OVER THE SOUTHERN PIEDMONT
AND SANDHILLS THIS MORNING. AS WITH YESTERDAY...THE HRRR HIGH RES
CAM IS DOING A GOOD JOB SIMULATING THE CURRENT SHOWER ACTIVITY. THE
LATEST RUN OF THE HRRR SHOWS AN INCREASE IN SHOWER COVERAGE...MAINLY
IN THE NORTHEAST PIEDMONT AND SANDHILLS THROUGH THIS AFTERNOON...
WITH THE MORE WIDESPREAD CONVECTION MOVING INTO THE NORTHWEST
PIEDMONT LATE THIS AFT/EVE. 12Z UPPER AIR ANALYSES SHOW THE LOW WEST
OF THE APPALACHIANS OVER IL/IN...WITH HIGH PRESSURE OFF THE CAROLINA
COAST. WHILE CENTRAL NC IS RELATIVELY DRY...LOW LEVEL MOISTURE IS
ADVECTING IN OFF THE GULF AHEAD OF THE LOW PRESSURE SYSTEM. AS THE
UPPER LEVEL LOW MOVES EASTWARD TODAY SO WILL THE LOW/MID LEVEL
MOISTURE AND SHOWERS/STORMS...CURRENTLY OVER THE MOUNTAINS. -KC
PRECIPITATION CHANCES:
SW FLOW ALOFT WILL STRENGTHEN FROM THE WEST TODAY...WITH AN
INCREASING POTENTIAL FOR SMALL AMPLITUDE SHORTWAVES TRACKING
NORTHEAST ACROSS WESTERN NC/VA THIS AFT/EVE...FOLLOWED BY ADDITIONAL
DPVA WITHIN INCREASINGLY CYCLONIC FLOW ALOFT AS THE UPPER LEVEL LOW
TRACKS INTO WESTERN PA BETWEEN 00-06Z TONIGHT. SHALLOW CONVERGENCE
IN VICINITY OF A DEVELOPING PIEDMONT SFC TROUGH ASSOCIATED WITH
SUBTLE HEIGHT FALLS IN ADVANCE OF THE UPPER LEVEL WAVE APPROACHING
THE REGION THIS AFT/EVE WILL SERVE AS A POTENTIAL FOCUS FOR DIURNAL
CONVECTION THIS AFTERNOON...FOLLOWED BY SOMEWHAT DEEPER CONVERGENCE
TONIGHT AS THE LOW-LEVEL TROUGH SHARPENS IN RESPONSE TO STRONGER
HEIGHT FALLS /CYCLONIC FLOW ALOFT/ OVER THE MID-ATLANTIC. SEASONAL
BOUNDARY LAYER MOISTURE/DESTABILIZATION CAN BE EXPECTED AGAIN THIS
AFTERNOON...WITH MLCAPE VALUES GENERALLY IN THE 1000-2000 J/KG RANGE
ACROSS CENTRAL NC...THOUGH A WEST-EAST MID-LEVEL MOISTURE GRADIENT
WILL PERSIST WITH DEEPER MOISTURE ACROSS THE FOOTHILLS/WESTERN
PIEDMONT AND A DRIER AIRMASS ALOFT IN THE COASTAL PLAIN. WITH THE
ABOVE IN MIND...EXPECT THE BEST CHANCE FOR CONVECTION THIS AFTERNOON
AND EARLY EVENING WEST OF THE HWY 1 CORRIDOR IN VICINITY OF THE
PIEDMONT SFC TROUGH AND IN CLOSER PROXIMITY TO SMALL AMPLITUDE
SHORTWAVES/DEEPER MOISTURE IN STRENGTHENING SW FLOW ALOFT. WILL
INDICATE PRECIP CHANCES RANGING FROM 20% EAST OF I-95 TO 50-60% IN
THE FAR W/NW PIEDMONT. CONVECTION SHOULD PERSIST INTO TONIGHT ACROSS
THE NORTHERN AND WESTERN PIEDMONT AS BETTER DPVA /STRONGER CYCLONIC
FLOW ALOFT/ PROGRESSES INTO THE MID-ATLANTIC.
TEMPERATURES:
EXPECT HIGHS TODAY SIMILAR TO PREVIOUS DAYS WITH VERY SIMILAR
REASONING...THOUGH PERHAPS SLIGHTLY WARMER GIVEN A MORE
SOUTHWESTERLY LOW-LEVEL FLOW...ESP. ALONG AND EAST OF THE HWY 1
CORRIDOR...WITH HIGHS RANGING FROM THE MID 80S FAR NW PIEDMONT TO
UPPER 80S AND LOWER 90S ELSEWHERE. LOWS TONIGHT SIMILAR TO PREVIOUS
NIGHTS IN THE LOWER 70S.
SEVERE THREAT:
GIVEN DEEP LAYER SHEAR IN THE 25-35 KT RANGE ACROSS THE N/NW
PIEDMONT IN THE PRESENCE OF MODERATE INSTABILITY (1000-2000 J/KG
MLCAPE) AND DCAPE VALUES PROGGED AS HIGH AS 1000-1500 J/KG THIS AFT
AND EARLY EVE...ANTICIPATE A POTENTIAL FOR DAMAGING WINDS...
PRIMARILY WEST AND NW OF THE TRIANGLE. -VINCENT
&&
.SHORT TERM /MONDAY/...
AS OF 325 AM SUNDAY...
ALTHOUGH THE AFOREMENTIONED UPPER LEVEL WAVE WILL TRACK EAST THROUGH
THE MID-ATLANTIC EARLY MONDAY MORNING...CYCLONIC FLOW ALOFT AND
LOW-LEVEL TROUGHING WILL PERSIST ACROSS THE AREA MONDAY
AFT/EVE...WITH ADDITIONAL SHORTWAVE ENERGY ANTICIPATED TO DIG
SOUTHEAST INTO NC/VA IN VICINITY OF PEAK HEATING. AS A RESULT...
EXPECT ABOVE NORMAL CHANCES FOR CONVECTION...PRIMARILY DURING THE
AFTERNOON AND EVENING HOURS...WITH HIGHS SIMILAR TO PREVIOUS DAYS...
IN THE MID/UPPER 80S TO NEAR 90F. -VINCENT
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
NWP GUIDANCE IS IN GOOD AGREEMENT OF ANOTHER PERIOD OF UNSETTLED
WEATHER WITH ABOVE NORMAL CHANCES OF PRECIPITATION FOR THE UPCOMING
WEEK. THE EXTENDED RANGE WILL FEATURE A PERSISTENT AND STRONG RIDGE
ACROSS THE SOUTHERN ROCKY MOUNTAINS AND A WEAKER BUT RELATIVELY
STATIONARY AREA OF RIDGING OFF THE SOUTHEAST U.S. COAST. A SLOWLY
WESTWARD ADVANCING CLOSED UPPER LOW MOVES WEST UNDER THE SUBTROPICAL
ATLANTIC RIDGE REACHING FLORIDA ON TUESDAY AND THEN MOVES INTO THE
EASTERN GULF OF MEXICO ON WEDNESDAY AND THURSDAY. A DIGGING SHORT
WAVE TROUGH AND ASSOCIATED COLD FRONT DROPS INTO THE GREAT LAKES
REGION ON WEDNESDAY REACHING THE MID ATLANTIC LATE THURSDAY AND THEN
CLOSES OFF ON FRIDAY. THIS UPPER LOW DRIFTS SOUTHWEST INTO THE
EASTERN TENNESSEE VALLEY BY SATURDAY. THE AIR MASS THROUGH THE
PERIOD WILL REMAIN MOIST AND UNSTABLE WITH AN AXIS OF HIGH
PRECIPITABLE WATER LINGERING ACROSS THE CAROLINAS AND VIRGINIA
THROUGH MOST/ALL OF THE PERIOD.
SENSIBLE WEATHER CONDITIONS WILL FEATURE AN UNSETTLED SUMMERTIME
PATTERN WITH A HUMID AIR MASS AND THE THREAT OF MAINLY AFTERNOON AND
EVENING CONVECTION EACH DAY. THE THREAT OF CONVECTION WILL BE
GREATEST ON THURSDAY AND THURSDAY NIGHT WHEN NWP GUIDANCE IS IN GOOD
AGREEMENT THAT A SHORTWAVE TROUGH AND COLD FRONT WILL APPROACH THE
REGION. UNSETTLED WEATHER WITH ABOVE CLIMATOLOGY POPS WILL LIKELY
PERSIST ON FRIDAY THROUGH SATURDAY ALTHOUGH THERE IS STILL SOME
UNCERTAINTY ON WHERE THE SURFACE BOUNDARY AND MAIN MOISTURE FEED
WILL SETUP. NEAR SEASONABLE TEMPERATURES ARE EXPECTED WITH HIGHS
AROUND 90 WITH MORNING LOWS IN THE LOWER TO MID 70S. -BLAES
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
AS OF 125 PM SUNDAY...
24-HR TAF PERIOD:
CIGS HAVE BEEN BORDERLINE VFR/MVFR ALL DAY...BOUNCING BACK AND FORTH
BETWEEN THE TWO...AND WILL LIKELY CONTINUE TO BE SO THROUGH MONDAY
MORNING. LIGHT SHOWERS ARE OCCURRING AROUND KRDU...WITH HEAVIER
SHOWERS AND POSSIBLE THUNDER MOVING INTO THE TRIAD (KINT AND KGSO)
THIS AFTERNOON AND INTO THE OVERNIGHT HOURS. BEST CHANCE FOR LOW-END
MVFR CIGS AT KINT AND KGSO DURING THE PRE-DAWN HOURS MONDAY...WITH
THE POTENTIAL FOR A PERIOD OF BORDERLINE VFR/MVFR CIGS ELSEWHERE...
ALTHOUGH CONFIDENCE IS LOW GIVEN THE DIFFERENCES IN MODEL GUIDANCE
AT THIS TIME. THERE IS THE CHANCE FOR SHOWERS TO REDEVELOP ACROSS
THE AREA MONDAY AFTERNOON/EVENING...BUT WILL LEAVE MENTION OUT OF
TAFS FOR NOW. -KC
LOOKING AHEAD:
AVIATION CONDITIONS THROUGH MID/LATE WEEK WILL BE CHARACTERIZED BY
AN ABOVE NORMAL CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY
(PRIMARILY AFTERNOON AND EVENING HOURS) IN ASSOCIATION WITH CYCLONIC
FLOW ALOFT AND AN ABOVE NORMAL CHANCE FOR MVFR/IFR STRATUS OR FOG
EACH MORNING (PRIMARILY 07-13Z) IN ASSOCIATION WITH A PERSISTENT
MOIST SOUTHERLY RETURN FLOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...KC/VINCENT
SHORT TERM...VINCENT
LONG TERM...BLAES
AVIATION...KC/VINCENT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
142 PM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 111 PM CDT SUN JUL 7 2013
UPDATE FOR ADDITIONAL ADJUSTMENTS TO POPS THROUGH TONIGHT...AND
MIDDAY TEMP TRENDS. CLOUDS HAVE INHIBITED TEMPS AT MANY
LOCATIONS...ESPECIALLY THE FAT SOUTH...BUT PARTIAL CLEARING IS
EXPECTED AS THE AFTERNOON PROGRESSES. A FEW STRONG STORMS ARE
POSSIBLE SOUTHWEST LATE THIS AFTERNOON AND EVENING IN THE AREA OF
GREATEST INSOLATION. THE LATEST HRRR AND 12 WRF ALL DEVELOP
CONVECTION AROUND 21Z-22Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUL 7 2013
EARLY MORNING SURFACE ANALYSIS PLACED A WEAK SURFACE TROUGH ACROSS
EASTERN NORTH DAKOTA. THE TROUGH WAS THE FOCUS FOR ISOLATED
THUNDERSTORMS EARLIER THIS MORNING...BUT THEY HAVE SINCE
DIMINISHED. THE TROUGH WILL MOVE SLOWLY EAST THIS MORNING...TAKING
THE THREAT OF ADDITIONAL THUNDERSTORMS WITH IT.
THE NEXT CONCERN WILL BE SHOWERS / THUNDERSTORMS IN EASTERN
MONTANA WHICH HAVE BEEN MAKING STEADY PROGRESS TOWARDS WESTERN
NORTH DAKOTA EARLY THIS MORNING. THE STORMS IN EASTERN MONTANA ARE
IN PART BEING DRIVEN BY A SHORT WAVE WHICH IS EXPECTED TO MOVE
INTO WESTERN NORTH DAKOTA THIS MORNING...AND INTO CENTRAL NORTH
DAKOTA THIS AFTERNOON. VARIOUS MODEL SOLUTIONS (NAM / RAP / GFS /
4KM WRF) ALL SUGGEST THERE WILL BE A CHANCE OF PRECIPITATION AS
THE WAVE MOVES ACROSS THE FORECAST AREA. WHERE THEY DIFFER TO SOME
EXTENT IS IN THEIR COVERAGE OF PRECIPITATION. WILL HOLD ONTO
CHANCE POPS ACROSS MOST OF THE FORECAST AREA TODAY / THIS EVENING
WITH THE HIGHER POPS IN THE WEST. THE LATEST DAY 1 OUTLOOK PLACES
THE SOUTHWEST PART OF THE STATE IN A SLIGHT RISK...WHICH APPEARS
REASONABLE SINCE THAT AREA IS FORECAST TO HAVE THE GREATEST
INSTABILITY THIS AFTERNOON / EVENING WITH MLCAPE VALUES OF UP TO
1500 J/KG.
CONFIDENCE IN THUNDERSTORM COVERAGE LATE TONIGHT INTO EARLY MONDAY
MORNING DECREASES TO SOME EXTENT AS THE INITIAL WAVE MOVES EAST.
CONFLICTING SIGNALS ARE SHOWN IN THE MODEL SOLUTIONS WITH SOME
SUGGESTING LIMITED THUNDERSTORM COVERAGE OVERNIGHT...WHILE OTHERS
BRING ADDITIONAL THUNDERSTORMS INTO WESTERN NORTH DAKOTA FROM
EASTERN MONTANA. WILL HOLD ONTO CHANCE POPS IN THE CENTRAL AND
WEST...WITH SLIGHT CHANCES IN THE EAST WHERE CONFIDENCE IN
ADDITIONAL CONVECTION IS LOWER.
CLOUDS FROM SHOWERS / THUNDERSTORMS COULD INFLUENCE TEMPERATURES
TODAY. WILL FOLLOW A BLEND OF GUIDANCE VALUES WITH HIGHS NEAR 80
NORTH...AND LOWER TO MID 80S SOUTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUL 7 2013
MODELS AGREE IN A SOUTHWEST FLOW ALOFT FROM THE NORTHWEST US TO
THE NORTHERN PLAINS EARLY IN THE PERIOD. AN ACTIVE SHORTWAVE
PATTERN WILL BRING SEVERAL SHORTWAVES THROUGH THE REGION BRINGING
SOME WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE REGION MONDAY
NIGHT AND TUESDAY. THIS WILL BE FOLLOWED BY A BREAK IN THE
PRECIPITATION CHANCES WEDNESDAY AND THURSDAY AS AN H500 RIDGE
POSITIONS ITSELF OVER THE NORTHERN PLAINS. AS THIS FEATURE MOVES
EAST BY NEXT WEEKEND WILL SEE AT LEAST A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS RETURN FOR FRIDAY AND SATURDAY.
THE PRIMARY FOCUS WILL BE MONDAY NIGHT. BY MONDAY AFTERNOON LOW
PRESSURE WILL DEVELOP ACROSS MONTANA BRINGING A EASTERLY WIND FLOW
ACROSS WEST AND CENTRAL NORTH DAKOTA. THIS WILL PULL ABUNDANT
MOISTURE INTO THE REGION. MODEL SOUNDINGS FORECAST PWATS BETWEEN
1.5 AND 1.75 INCHES...OR ROUGHLY 2 STANDARD DEVIATIONS ABOVE
NORMAL IF CORRECT. WITH ABUNDANT MOISTURE WILL MENTION HEAVY RAIN
IN THE HWO ALONG WITH SLIGHT CHANCE SEVERE FROM SPC MONDAY NIGHT.
THUNDERSTORMS WILL END TUESDAY FOLLOWED BY THE DRY WEATHER
WEDNESDAYS AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 111 PM CDT SUN JUL 7 2013
WESTERN NORTH DAKOTA WILL BE THE PRIMARY FOCUS FOR SCATTERED
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING...MAINLY IMPACTING
KDIK/KISN. STORMS ARE EXPECTED TO BE TOO SCATTERED IN NATURE TO
WARRANT MORE THAN VCTS GROUPS AT THIS TIME. OTHER THAN BRIEF MVFR
VSBYS IN THE MORE INTENSE STORMS...EXPECT VFR CONDITIONS.
ADDITIONAL SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE TOWARD
DAYBREAK AT KMOT...THEN BY MID MORNING AT KDIK/KBIS/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...CK
LONG TERM...WAA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
559 PM EDT SUN JUL 7 2013
.SYNOPSIS...
UPPER LEVEL LOW MOVES EAST TONIGHT. NORTHWEST FLOW THROUGH
WEDNESDAY BRINGS MORE CONVECTION. A COLD FRONT PUSHES SOUTHEAST
WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
CLOUDS HAVE PREVENTED MUCH ENERGY FROM BUILDING UP IN AREAS THAT
STILL HAVE DEEPER MOISTURE. THEREFORE...SHOWERS ARE ONLY PRODUCING
UP TO HALF AN INCH OF RAINFALL. WILL CANCEL FLASH FLOOD WATCH.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH WEDNESDAY/...
MODELS CONTINUE TO ADVERTISE THAT WEST/NORTHWEST UPPER FLOW WILL
DEVELOP WITH UPPER DISTURBANCES EXPECTED TO MOVE ACROSS THE AREA.
AT THE SURFACE...WEAK HIGH PRESSURE WILL GIVE WAY...ALLOWING A
COLD FRONT TO APPROACH LATE.
THE COMBINATION OF UPPER DISTURBANCES AND GULF MOISTURE WILL RESULT
IN ON AND OFF AGAIN SHOWER AND STORM CHANCES WITH THUNDERSTORM
COMPLEXES ROLLING FROM NORTHWEST TO SOUTHEAST REMAINING POSSIBLE.
AS FRONT BEGINS TO APPROACH FROM THE NORTHWEST ON WEDNESDAY...SHOWER
AND STORMS CHANCES SHOULD RAMP UP...AND HAVE INCLUDED LIKELY POPS
ACROSS OUR SOUTHEAST OHIO COUNTIES FOR WEDNESDAY AFTERNOON.
MAX TEMPERATURES WILL BE NEAR NORMAL...BUT IT WILL BE RATHER HUMID.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GENERALLY FOLLOWED WPC THINKING FOR THIS PORTION OF THE FORECAST...
WITH SOME TWEAKS.
COLD FRONT IS EXPECTED TO PUSH SOUTHEAST WEDNESDAY NIGHT AND
THURSDAY...WITH WEAK HIGH PRESSURE SLIDING BY TO OUR NORTH FRIDAY
THROUGH SUNDAY. GFS/ECMWF BOTH ADVERTISE AN UPPER LOW WILL DEVELOP
FRIDAY NIGHT...WITH A TROF EXTENDING SOUTHWEST ACROSS THE REGION.
A SECOND UPPER LOW IS EXPECTED TO DEVELOP TO OUR SOUTH ON SATURDAY
AND THEN RETROGRADE WITH TIME.
COMBINATION OF COLD FRONT AND THE UPPER LOWS SUGGEST ANOTHER
EXTENDED PERIOD OF WET WEATHER FOR MUCH OF THIS PERIOD.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
RADAR IMAGES SHOW THE BULK OF PCPN OVER THE HIGHER MOUNTAINS BY
18Z. A NEW LINE OF WEAK CONVECTION IS EVIDENT IN
RADAR...DEVELOPING OVER SOUTHEAST OH. THESE SHOWERS WILL CONTINUE
TO INCREASE INTO STORMS TO PRODUCE LIGHTNING. THE HRRR...NAM AND
RAP DEVELOP THIS LINE OVER THE OH RIVER BY 21Z...SPREADING
NORTHEAST AS IT WEAKENS BY SUNSET. THIS SECOND LINE OF CONVECTION
COULD PRODUCE IFR VISIBILITIES AND THUNDER MAINLY AT
HTS...PKB...AND CRW THROUGH 22Z THIS AFTERNOON. WITH NO LIGHTNING
OCCURRING WITH BACK EDGE OF PCPN...AND THERMODYNAMIC AND DYNAMIC
PARAMETERS INDICATED BY RAP AND NAM...KEPT THUNDER OR VCTS OVER
EASTERN SITES ALONG THE OH RIVER.
WATER VAPOR SATELLITE IMAGES SHOW BACK EDGE OF HIGH CLOUDS MARKING
THE UPPER LEVEL JET ACROSS OH...EXTENDING SOUTH INTO NORTHEAST KY.
A CONCENTRATED DRY SLOT AROUND THE UPPER LOW SUGGESTS
STRATOSPHERIC INTRUSION AROUND THE LOW AT THE BASE...SPREADING
INTO ITS SOUTHEAST QUADRANT. THESE FEATURES SUGGEST FRONTOGENESIS
POSSIBLE AT THE MID LEVELS...THAT COULD ENHANCE THE LATER
CONVECTION TO FLARE UP INTO GUSTY THUNDERSTORMS THROUGH SUNSET.
ABUNDANT LOW LEVEL MOISTURE WILL KEEP POST RAINFALL LOW STRATUS
OVER THE WESTERN SLOPES AND EASTERN MOUNTAINS TONIGHT...WITH
CONDITIONS DETERIORATING OVERNIGHT. EXPECT IFR/LIFR STRATUS AT BKW
AND EKN AFTER 06Z THROUGH 13Z MONDAY MORNING.
CONDITIONS EXPECTED TO IMPROVE WIDESPREAD TO VFR BY 15Z MONDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS COULD VARY BY A
COUPLE HOURS. IFR/LIFR FOG OR LOW STRATUS TIMING MAY VARY
OVERNIGHT IF SKIES CLEAR FASTER THAN ANTICIPATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H M M H
HTS CONSISTENCY M H H H H H H H H M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H M M L L
PKB CONSISTENCY M H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H M M M
AFTER 00Z TUESDAY...
IFR FOG POSSIBLE LATE SUNDAY NIGHT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/ARJ
NEAR TERM...RPY
SHORT TERM...JSH
LONG TERM...JSH
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
237 PM EDT SUN JUL 7 2013
.SYNOPSIS...
UPPER LEVEL LOW MOVES EAST TONIGHT. NORTHWEST FLOW THROUGH
WEDNESDAY BRINGS MORE CONVECTION. A COLD FRONT PUSHES SOUTHEAST
WEDNESDAY NIGHT AND THURSDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
HRRR...RAP AND NAM MODELS SHOW A WEAK LINE OF CONVECTION
DEVELOPING ACROSS THE OH VALLEY...SPREADING NORTHEAST AND
WEAKENING BY SUNSET. FLASH FLOOD WATCH CONTINUES IN EFFECT FOR THE
MOST PART...EXCEPT FOR SOUTHEAST OH...AND FEW COUNTIES IN
NORTHEAST KY.
UPPER LOW CROSSING THE IN AND OH BORDER EVIDENT IN WATER VAPOR
IMAGES WILL CONTINUE ITS TRAJECTORY EAST INTO OH AND WV OVERNIGHT
INTO MONDAY. THE LEADING EDGE OF UPPER/MID CLOUDS ASSOCIATED WITH
UPPER LEVEL JET WILL SPREAD AREAS OF CLEARING FROM NORTHEAST
KY...EAST ACROSS SOUTHEAST OH AND PORTIONS OF WV TONIGHT. THIS
CLEARING IS SUGGESTED BY THE NAM/CMC AND AT SOME DEGREE THE GMOS.
WIDESPREAD DENSE FOG POSSIBLE OVER AREAS WHERE SKY CLEARS
OVERNIGHT AS ANTECEDENT PCPN WAS WIDESPREAD AND AMPLE LOW LEVEL
MOISTURE WITH DEWPOINTS IN THE MID TO UPPER 60S. MODELS SHOW
BOUNDARY LAYER WINDS AROUND 10 KNOTS TONIGHT INTO MONDAY.
WENT CLOSER TO MAX DEWPOINTS DURING THE AFTERNOON HOURS FOR LOWS
TONIGHT. BIAS CORRECTED USED FOR HIGHS ON MONDAY...GENERALLY IN
THE LOWER 80S LOWLANDS...RANGING TO THE MID 70S HIGHEST
ELEVATIONS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
MODELS CONTINUE TO ADVERTISE THAT WEST/NORTHWEST UPPER FLOW WILL
DEVELOP WITH UPPER DISTURBANCES EXPECTED TO MOVE ACROSS THE AREA.
AT THE SURFACE...WEAK HIGH PRESSURE WILL GIVE WAY...ALLOWING A
COLD FRONT TO APPROACH LATE.
THE COMBINATION OF UPPER DISTURBANCES AND GULF MOISTURE WILL RESULT
IN ON AND OFF AGAIN SHOWER AND STORM CHANCES WITH THUNDERSTORM
COMPLEXES ROLLING FROM NORTHWEST TO SOUTHEAST REMAINING POSSIBLE.
AS FRONT BEGINS TO APPROACH FROM THE NORTHWEST ON WEDNESDAY...SHOWER
AND STORMS CHANCES SHOULD RAMP UP...AND HAVE INCLUDED LIKELY POPS
ACROSS OUR SOUTHEAST OHIO COUNTIES FOR WEDNESDAY AFTERNOON.
MAX TEMPERATURES WILL BE NEAR NORMAL...BUT IT WILL BE RATHER HUMID.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GENERALLY FOLLOWED WPC THINKING FOR THIS PORTION OF THE FORECAST...
WITH SOME TWEAKS.
COLD FRONT IS EXPECTED TO PUSH SOUTHEAST WEDNESDAY NIGHT AND
THURSDAY...WITH WEAK HIGH PRESSURE SLIDING BY TO OUR NORTH FRIDAY
THROUGH SUNDAY. GFS/ECMWF BOTH ADVERTISE AN UPPER LOW WILL DEVELOP
FRIDAY NIGHT...WITH A TROF EXTENDING SOUTHWEST ACROSS THE REGION.
A SECOND UPPER LOW IS EXPECTED TO DEVELOP TO OUR SOUTH ON SATURDAY
AND THEN RETROGRADE WITH TIME.
COMBINATION OF COLD FRONT AND THE UPPER LOWS SUGGEST ANOTHER
EXTENDED PERIOD OF WET WEATHER FOR MUCH OF THIS PERIOD.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
RADAR IMAGES SHOW THE BULK OF PCPN OVER THE HIGHER MOUNTAINS BY
18Z. A NEW LINE OF WEAK CONVECTION IS EVIDENT IN
RADAR...DEVELOPING OVER SOUTHEAST OH. THESE SHOWERS WILL CONTINUE
TO INCREASE INTO STORMS TO PRODUCE LIGHTNING. THE HRRR...NAM AND
RAP DEVELOP THIS LINE OVER THE OH RIVER BY 21Z...SPREADING
NORTHEAST AS IT WEAKENS BY SUNSET. THIS SECOND LINE OF CONVECTION
COULD PRODUCE IFR VISIBILITIES AND THUNDER MAINLY AT
HTS...PKB...AND CRW THROUGH 22Z THIS AFTERNOON. WITH NO LIGHTNING
OCCURRING WITH BACK EDGE OF PCPN...AND THERMODYNAMIC AND DYNAMIC
PARAMETERS INDICATED BY RAP AND NAM...KEPT THUNDER OR VCTS OVER
EASTERN SITES ALONG THE OH RIVER.
WATER VAPOR SATELLITE IMAGES SHOW BACK EDGE OF HIGH CLOUDS MARKING
THE UPPER LEVEL JET ACROSS OH...EXTENDING SOUTH INTO NORTHEAST KY.
A CONCENTRATED DRY SLOT AROUND THE UPPER LOW SUGGESTS
STRATOSPHERIC INTRUSION AROUND THE LOW AT THE BASE...SPREADING
INTO ITS SOUTHEAST QUADRANT. THESE FEATURES SUGGEST FRONTOGENESIS
POSSIBLE AT THE MID LEVELS...THAT COULD ENHANCE THE LATER
CONVECTION TO FLARE UP INTO GUSTY THUNDERSTORMS THROUGH SUNSET.
ABUNDANT LOW LEVEL MOISTURE WILL KEEP POST RAINFALL LOW STRATUS
OVER THE WESTERN SLOPES AND EASTERN MOUNTAINS TONIGHT...WITH
CONDITIONS DETERIORATING OVERNIGHT. EXPECT IFR/LIFR STRATUS AT BKW
AND EKN AFTER 06Z THROUGH 13Z MONDAY MORNING.
CONDITIONS EXPECTED TO IMPROVE WIDESPREAD TO VFR BY 15Z MONDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND STORMS COULD VARY BY A
COUPLE HOURS. IFR/LIFR FOG OR LOW STRATUS TIMING MAY VARY
OVERNIGHT IF SKIES CLEAR FASTER THAN ANTICIPATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H M M H
HTS CONSISTENCY M H H H H H H H H M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H M M L L
PKB CONSISTENCY M H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H M M M
AFTER 18Z MONDAY...
IFR FOG POSSIBLE LATE SUNDAY NIGHT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR WVZ005>011-
013>020-024>040-046-047.
OH...NONE.
KY...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR KYZ103-105.
VA...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ003-004.
&&
$$
SYNOPSIS...JSH/ARJ
NEAR TERM...ARJ
SHORT TERM...JSH
LONG TERM...JSH
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
624 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EASTERN SEABOARD WILL CONTINUE TO
FEED VERY WARM AND HUMID AIR NORTHWARD INTO THE COMMONWEALTH.
DAILY CHANCES OF AFTERNOON AND EVENING SHOWERS/THUNDERSTORMS WILL
PERSIST INTO THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
SEVERE THREAT WINDING DOWN RAPIDLY ACROSS FAR EASTERN PORTIONS OF
MY CWA. MODERATE SHOWERS CONTINUE OVER EASTERN HALF IN THE COLD
POOL AND WILL TAKE A FEW MORE HOURS TO DISSIPATE AND PROPOGATE
EASTWARD. ISOLATED ACTIVITY WILL STILL BE POSSIBLE FROM LATE
EVENING OVERNIGHT. ANOTHER MUGGY NIGHT IS IN STORE WITH AREAS OF
RIVER VALLEY FOG MORE PREVALENT THAT RECENT MORNINGS DUE TO
WIDESPREAD NATURE OF THIS AFTERNOON`S CONVECTION. MINS WILL RANGE
FROM THE LOWER 60S NORTHWEST TO THE LOWER 70S SOUTHEAST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH 6 PM MONDAY/...
SHORT RANGE GUIDANCE AGREES IN TRACKING THE REMNANTS OF THE
AMAZINGLY PERSISTENT UPPER LOW/TROF THROUGH THE REGION OVERNIGHT
AND EARLY MONDAY. THIS SYSTEM HAS ACTED AS A MOISTURE PUMP INTO
THE NE US FOR OVER A WEEK AND ITS DEMISE WILL MARK A TRANSITION
TO MORE OF A ZONAL FLOW ALOFT TO START THE NEW WORK WEEK.
THE BEST FORCING WITH THE UPPER LOW IS EXPECTED TO PASS LATER
TONIGHT...DURING THE NORMAL DIURNAL LULL IN INSTABILITY. IT WILL
LIKELY KEEP A BETTER CHANCE OF SHOWERS GOING DEEPER INTO THE
OVERNIGHT THAN PREVIOUS NIGHTS WITH LOCALLY HEAVY RAIN LIKELY
BEING THE BIGGEST THREAT.
MONDAY WILL REMAIN WARM AND HUMID AND SCATTERED CONVECTION ONCE
AGAIN CANNOT BE RULED OUT...BUT CHANCES SHOULD BE LESS THAN RECENT
DAYS. ENSEMBLES AGREE IN SHUNTING THE AXIS OF HIGHEST PWATS EAST
OF THE AREA...AND MID LEVEL HEIGHT RISES AND WARM ADVECTION SHOULD
ALL COMBINE TO LIMIT OUR INSTABILITY.
TEMPS FROM NEAR 80 IN THE NW...TO THE MID 80S IN THE SE WILL BE
VERY CLOSE TO NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AFTER THE PASSAGE OF THE UPPER LOW...THE UPPER PATTERN WILL BECOME
QUASI-ZONAL FOR A TIME EARLY TO MID WEEK...WITH PA BEING ON THE
SOUTHERN EDGE OF THE WESTERLIES. THE MODELS ARE CONSISTENT WITH
PERSISTENT MOIST WESTERLY FLOW WHICH WILL LEAVE THE REGION
VULNERABLE TO CONVECTION AS WEAK DISTURBANCES RIPPLE EASTWARD OUT
OF THE MIDWEST AND GREAT LAKES.
A STRONGER TROUGH WILL DEEPEN OVER SOUTHERN CANADA AND OVER THE
GREAT LAKES REGION TOWARDS THE END OF THE WEEK. THIS SHOULD RESULT
IN A FAIRLY STRONG FRONTAL PASSAGE SOMETIME LATER WED OR THU AS
SLIGHTLY COOLER BUT MUCH DRIER AIR SLIDES OUT OF THE GR LAKES.
FROM THERE THE UPPER PATTERN ADVERTISED IN SOME LONGER RANGE
GUIDANCE TAKES ON A LOOK THAT IS EERILY FAMILIAR TO WHAT WE HAVE
JUST EXPERIENCED...WITH A NEW CUTOFF LOW FCST TO FORM OVER THE
EASTERN US...AND A RENEWED SURGE OF DEEP SOUTHERLY FLOW
EVENTUALLY EXPECTED TO DEVELOP ONCE AGAIN OVER THE EASTERN US. A
POTENTIAL COMPLICATING FACTOR IS A TROPICAL SYSTEM CURRENTLY WELL
OUT IN THE ATLANTIC THAT THE TROPICAL MODELS TRACK INTO THE
BAHAMAS BY LATE WEEK...MAKING A TANTALIZING FEATURE FOR THE
EASTERN US TROF TO PERHAPS INTERACT WITH.
WHAT HAS BEEN INTERESTING SO FAR THIS JULY HAS BEEN THE RATHER
HIGH LATITUDE THE BERMUDA RIDGE HAS OCCUPIED FOR SO EARLY IN THE
SEASON. THE LATEST PROGS ONCE AGAIN HAVE A STRONG CLOSED UPPER
HIGH AT UNUSUALLY HIGH LATITUDES BY NEXT WEEKEND. IF THE TROPICAL
SYSTEM CAN MANAGE TO HOLD TOGETHER...IT WOULD SUGGEST THE EASTERN
SEABOARD WOULD BE VULNERABLE IN ABOUT A WEEK`S TIME. STAY TUNED.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
LINE OF THUNDERSTORMS...ACCOMPANIED BY BRIEF GUSTY WINDS AND IFR
VSBYS...IS PUSHING THRU THE SUSQ VALLEY AS OF 21Z. FOR MUCH OF
CENTRAL PA...EXPECT A RETURN TO VFR CONDS WITHIN A COUPLE HOURS
AFTER PASSAGE OF THUNDERSTORMS. HOWEVER...RESIDUAL LOW LVL
MOISTURE ASCENDING THE W MTNS COULD PRODUCE SOME LOW CIGS ACROSS
THE LAUREL HIGHLANDS THIS EVENING /JST REPORTING SCT009 AT 21Z AND
K2G4 REPORTING A 800FT CIG/. THE LOW CIG THREAT COULD SPREAD NORTH
ALONG THE ALLEGHENY MTNS TOWARD BFD LATE TONIGHT AS BLYR COOLS. LATEST
SREF AND RAP OUTPUT BOTH SUPPORT THIS THREAT OF IFR CONDS ACROSS
THE W MTNS. FURTHER EAST...FOG IS CERTAINLY A POSSIBILITY...GIVEN
THE WET GROUND AND PARTIAL CLEARING EXPECTED OVERNIGHT.
HOWEVER...PRES GRADIENT SUGGESTS THERE WILL BE ENOUGH OF A WIND TO
PRECLUDE IFR VSBYS.
AN UPPER LVL LOW WILL PUSH EAST TOWARD PA MONDAY. THIS WILL BRING
ANOTHER HIGH PROB OF SHRA AND TSRA.
OUTLOOK...
MON...AM LOW CIGS POSS W MTNS. ISOLD THUNDERSTORM IMPACTS.
TUE-THU...AM LOW CIGS POSS W MTNS. SCT THUNDERSTORM IMPACTS
POSS...MAINLY DURING THE PM HOURS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/RXR
NEAR TERM...DEVOIR/LA CORTE/RXR
SHORT TERM...LA CORTE
LONG TERM...LA CORTE/GARTNER
AVIATION...FITZGERALD/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
536 PM EDT SUN JUL 7 2013
.SYNOPSIS...
A BERMUDA HIGH ANCHORED OFF THE EASTERN SEABOARD WILL CONTINUE TO
FEED VERY WARM AND HUMID AIR NORTHWARD INTO THE COMMONWEALTH.
DAILY CHANCES OF AFTERNOON AND EVENING SHOWERS/THUNDERSTORMS WILL
PERSIST INTO THE UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MORE OF THE SAME IN STORE FOR TODAY...WARM AND HUMID WITH SHOWERS
AND THUNDERSTORMS COOKING UP WITH DAYTIME HEATING.
MODELS GENERATE THE MOST CAPE OVER EASTERN SECTIONS TODAY...IN
RESPONSE TO WHERE THE BEST SUNSHINE IS EXPECTED TO BE. THE ENTIRE
REGION WILL REMAIN IN THE TROPICAL AIRMASS ABOVE NORMAL PWATS
CONTINUE TO STREAM NORTH INTO THE AREA.
SPC DOESN/T OUTLOOK THE REGION TODAY...THOUGH WE ARE IN SEE TEXT.
THE SHEAR ALOFT IS FAIRLY IMPRESSIVE ON THE FRONT SIDE OF THE
UPPER LOW THAT IS FINALLY BEGINNING TO SHEAR OUT OF THE TN/OH
VALLEYS. AS A RESULT WE CANNOT RULE OUT SOME ISOLATED STRONGER
STORMS AS ACTIVITY INCREASES LATER THIS MORNING INTO THE
AFTERNOON. LOW LEVEL FOCUSING IS WEAK...SO WIDESPREAD ORGANIZED
ACTIVITY DOESN/T SEEM LIKELY ACROSS THE NORTH. HOWEVER...A SUBTLE
WAVE DRIFTING NORTH IN THE MID-LEVEL FLOW /YESTERDAY LOCATED IN W
NC/ WILL PROVIDE A BIT MORE FOCUSED LIFT ACROSS THE SOUTH...AND
COMBINED WITH MODERATE FLOW AND CAPE...COULD GENERATE MORE
ORGANIZED ACTIVITY WITH SOME STRONGER STORMS POSS. THIS IS ALSO
NOTED IN THE HRRR...WHICH HAS BEEN PERFORMING WELL OVER THE PAST
COUPLE OF DAYS. ACTIVITY LOOKS TO BEGIN PICKING UP AFTER 18Z IN
THE SW...AND IF SCENARIO PLAYS OUT - TRACKING EASTWARD THROUGH THE
AFTERNOON HOURS.
HIGHS TODAY LOOK LIKE THEY WILL NOT BE MUCH DIFFERENT THAN SUNDAY.
ANOTHER VERY SUMMERY EARLY JULY DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
SHORT RANGE GUIDANCE AGREES IN TRACKING THE REMNANTS OF THE
AMAZINGLY PERSISTENT UPPER LOW/TROF THROUGH THE REGION OVERNIGHT
AND EARLY MONDAY. THIS SYSTEM HAS ACTED AS A MOISTURE PUMP INTO
THE NE US FOR OVER A WEEK AND ITS DEMISE WILL MARK A TRANSITION
TO MORE OF A ZONAL FLOW ALOFT TO START THE NEW WORK WEEK.
THE BEST FORCING WITH THE UPPER LOW IS EXPECTED TO PASS LATER
TONIGHT...DURING THE NORMAL DIURNAL LULL IN INSTABILITY. IT WILL
LIKELY KEEP A BETTER CHANCE OF SHOWERS GOING DEEPER INTO THE
OVERNIGHT THAN PREVIOUS NIGHTS WITH LOCALLY HEAVY RAIN LIKELY
BEING THE BIGGEST THREAT.
MONDAY WILL REMAIN WARM AND HUMID AND SCATTERED CONVECTION ONCE
AGAIN CANNOT BE RULED OUT...BUT CHANCES SHOULD BE LESS THAN RECENT
DAYS. ENSEMBLES AGREE IN SHUNTING THE AXIS OF HIGHEST PWATS EAST
OF THE AREA...AND MID LEVEL HEIGHT RISES AND WARM ADVECTION SHOULD
ALL COMBINE TO LIMIT OUR INSTABILITY.
TEMPS FROM NEAR 80 IN THE NW...TO THE MID 80S IN THE SE WILL BE
VERY CLOSE TO NORMAL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AFTER THE PASSAGE OF THE UPPER LOW...THE UPPER PATTERN WILL BECOME
QUASI-ZONAL FOR A TIME EARLY TO MID WEEK...WITH PA BEING ON THE
SOUTHERN EDGE OF THE WESTERLIES. THE MODELS ARE CONSISTENT WITH
PERSISTENT MOIST WESTERLY FLOW WHICH WILL LEAVE THE REGION
VULNERABLE TO CONVECTION AS WEAK DISTURBANCES RIPPLE EASTWARD OUT
OF THE MIDWEST AND GREAT LAKES.
A STRONGER TROUGH WILL DEEPEN OVER SOUTHERN CANADA AND OVER THE
GREAT LAKES REGION TOWARDS THE END OF THE WEEK. THIS SHOULD RESULT
IN A FAIRLY STRONG FRONTAL PASSAGE SOMETIME LATER WED OR THU AS
SLIGHTLY COOLER BUT MUCH DRIER AIR SLIDES OUT OF THE GR LAKES.
FROM THERE THE UPPER PATTERN ADVERTISED IN SOME LONGER RANGE
GUIDANCE TAKES ON A LOOK THAT IS EERILY FAMILIAR TO WHAT WE HAVE
JUST EXPERIENCED...WITH A NEW CUTOFF LOW FCST TO FORM OVER THE
EASTERN US...AND A RENEWED SURGE OF DEEP SOUTHERLY FLOW
EVENTUALLY EXPECTED TO DEVELOP ONCE AGAIN OVER THE EASTERN US. A
POTENTIAL COMPLICATING FACTOR IS A TROPICAL SYSTEM CURRENTLY WELL
OUT IN THE ATLANTIC THAT THE TROPICAL MODELS TRACK INTO THE
BAHAMAS BY LATE WEEK...MAKING A TANTALIZING FEATURE FOR THE
EASTERN US TROF TO PERHAPS INTERACT WITH.
WHAT HAS BEEN INTERESTING SO FAR THIS JULY HAS BEEN THE RATHER
HIGH LATITUDE THE BERMUDA RIDGE HAS OCCUPIED FOR SO EARLY IN THE
SEASON. THE LATEST PROGS ONCE AGAIN HAVE A STRONG CLOSED UPPER
HIGH AT UNUSUALLY HIGH LATITUDES BY NEXT WEEKEND. IF THE TROPICAL
SYSTEM CAN MANAGE TO HOLD TOGETHER...IT WOULD SUGGEST THE EASTERN
SEABOARD WOULD BE VULNERABLE IN ABOUT A WEEK`S TIME. STAY TUNED.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
LINE OF THUNDERSTORMS...ACCOMPANIED BY BRIEF GUSTY WINDS AND IFR
VSBYS...IS PUSHING THRU THE SUSQ VALLEY AS OF 21Z. FOR MUCH OF
CENTRAL PA...EXPECT A RETURN TO VFR CONDS WITHIN A COUPLE HOURS
AFTER PASSAGE OF THUNDERSTORMS. HOWEVER...RESIDUAL LOW LVL
MOISTURE ASCENDING THE W MTNS COULD PRODUCE SOME LOW CIGS ACROSS
THE LAUREL HIGHLANDS THIS EVENING /JST REPORTING SCT009 AT 21Z AND
K2G4 REPORTING A 800FT CIG/. THE LOW CIG THREAT COULD SPREAD NORTH
ALONG THE ALLEGHENY MTNS TOWARD BFD LATE TONIGHT AS BLYR COOLS. LATEST
SREF AND RAP OUTPUT BOTH SUPPORT THIS THREAT OF IFR CONDS ACROSS
THE W MTNS. FURTHER EAST...FOG IS CERTAINLY A POSSIBILITY...GIVEN
THE WET GROUND AND PARTIAL CLEARING EXPECTED OVERNIGHT.
HOWEVER...PRES GRADIENT SUGGESTS THERE WILL BE ENOUGH OF A WIND TO
PRECLUDE IFR VSBYS.
AN UPPER LVL LOW WILL PUSH EAST TOWARD PA MONDAY. THIS WILL BRING
ANOTHER HIGH PROB OF SHRA AND TSRA.
OUTLOOK...
MON...AM LOW CIGS POSS W MTNS. ISOLD THUNDERSTORM IMPACTS.
TUE-THU...AM LOW CIGS POSS W MTNS. SCT THUNDERSTORM IMPACTS
POSS...MAINLY DURING THE PM HOURS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/RXR
NEAR TERM...LA CORTE/RXR
SHORT TERM...LA CORTE
LONG TERM...LA CORTE/GARTNER
AVIATION...FITZGERALD/RXR
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1237 PM CDT SUN JUL 7 2013
.UPDATE...
ISSUED AT 1054 AM CDT SUN JUL 7 2013
INTERESTING FORECAST FOR TODAY. WEAK UPPER WAVE GENERATING AN AREA
OF ELEVATED SHOWERS AND STORMS ACROSS CENTRAL SOUTH DAKOTA THIS
MORNING. AS THIS WAVE MOVES EAST OUR CWA WILL SEE WEAK UPPER FORCING
FOR ASCENT. EXPECT CIRRUS FROM THIS ACTIVITY TO WORK ITS WAY INTO
OUR WESTERN CWA AS WE HEAD INTO THIS AFTERNOON. MEANWHILE FRONTAL
BOUNDARY IS TAKING ITS SLOW TIME MOVING SOUTH ACROSS OUR CWA. SO
QUESTION BECOMES WHAT ARE OUR CONVECTION CHANCES THIS AFTERNOON. A
COUPLE THINGS TO WATCH WILL BE DEWPOINT EVOLUTION AND CONVECTIVE
EVOLUTION ACROSS CENTRAL AND WESTERN SOUTH DAKOTA.
MOISTURE POOLING BEHIND THE FRONT IS CURRENTLY ALLOWING DEWPOINTS TO
CREEP INTO THE LOW 70S IN SPOTS. A LOT OF GUIDANCE SUGGEST THESE
DEWPOINTS MAY STRUGGLE TO MIX OUT...WITH RELATIVELY DEEP MOISTURE
PRESENT UP TO ABOUT 850 MB...AND WEAK FLOW. AS TEMPERATURES RISE
INTO THE 80S THIS AFTERNOON...MLCAPE COULD END UP IN THE 2000 TO
3000 J/KG RANGE IN THE AREA OF MOISTURE POOLING. CIN WOULD ALSO
BECOME ALMOST ZERO. HOWEVER A VERY DRY LAYER AROUND 700 MB WILL
LIKELY HINDER UPDRAFTS SOMEWHAT...AND DESPITE THE BOUNDARY
NEARBY...SEE VERY LITTLE IN THE WAY OF LOW LEVEL CONVERGENCE OR
FORCING FOR ASCENT. SO IT WOULD COME DOWN TO WHETHER THE INSTABILITY
AND WEAK UPPER FORCING WOULD BE ENOUGH TO GET DEEP CU THROUGH THE
DRY AIR. HI RES GUIDANCE...SUCH AS THE 06Z WRF ARW AND 12Z 4KM NAM
BOTH SUGGEST THIS MAY HAPPEN. THUS WENT AHEAD AND ADDED IN A SLIGHT
CHANCE OF STORMS THIS AFTERNOON AND EVENING ACROSS PORTIONS OF OUR
CWA. AGAIN THIS IS REALLY DEPENDENT ON IF WE CAN KEEP DEWPOINTS IN
THE LOWER 70S. IF THEY FAIL TO MATERIALIZE...THEN DRY AIR ALOFT AND
WARM LAYER BETWEEN 800 AND 600 MB WILL LIKELY BE ENOUGH TO CAP
CONVECTION. WIND SHEAR IS WEAK...THUS ANY STORM WOULD BE PULSE OR
POSSIBLY MULTICELL TYPE. BUT GIVEN WHAT WOULD BE HIGH
INSTABILITY...WOULD EXPECT AT LEAST THE THREAT OF QUARTER SIZE HAIL
AND 60 MPH WIND GUSTS IN ANY STORM. HRRR DEVELOPS CONVECTION IN
CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND MOVES IT INTO OUR WESTERN
CWA LATER THIS AFTERNOON AND EVENING. GIVEN EXTENSIVE CLOUD COVER IN
THIS AREA...FEEL SURFACE BASED INITIATION IN CENTRAL SOUTH DAKOTA IS
UNLIKELY THIS AFTERNOON...THUS BELIEVE THE HRRR SOLUTION IS PROBABLY
NOT ACCURATE...AND SO WILL HOLD OFF ON ADDING IN ANY POPS IN OUR
WEST THROUGH 0Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SUN JUL 7 2013
TODAY AND MUCH OF TONIGHT SHOULD REMAIN QUIET IN OUR AREA DESPITE
MESSY...WAVE-RIDDLED MID LEVEL FLOW PATTERN BETWEEN DOMINANT RIDGE
BUILDING WESTWARD ACROSS THE SOUTHERN CONUS AND VARIOUS TROUGHS
TRACKING EASTWARD THROUGH THE CANADIAN PRAIRIES. IN THE NEAR TERM...
SEEING SOME ACCAS AND SPOTTY SHOWERS DEVELOP IN WESTERN IOWA AHEAD OF
WEAK WAVE. SHOWERS ARE NOT EXPECTED TO IMPACT OUR FORECAST AREA THIS
MORNING THOUGH COULD SEE A LITTLE OF THE ACCAS IN OUR FAR EAST EARLY
BEFORE WEAK WAVE PASSES BY. WEAK SURFACE BOUNDARY STILL WEST OF I-29
AS OF 08Z MOVING SOUTHEAST MORE SLOWLY THAN EXPECTED AT THIS TIME
YESTERDAY...THOUGH STILL EXPECTED TO MAKE SOME EASTWARD PROGRESS
THROUGH THE DAY...REACHING NEAR/JUST EAST OF HIGHWAY 60 CORRIDOR
IN NORTHWEST IOWA BY LATE AFTERNOON. WITH WEAK LOW LEVEL
FLOW...EXPECT HIGHER MOISTURE LEVELS TO POOL NEAR THE
BOUNDARY...WITH DEW POINTS IN NORTHWEST IOWA NEAR 70 WHILE
TEMPERATURES CLIMB INTO THE LOWER 90S THIS AFTERNOON. THIS SHOULD
LEAD TO FAIR AMOUNT OF INSTABILITY WHICH COULD POP A STRAY STORM
OR TWO WITH WEAK CONVERGENCE ALONG THE BOUNDARY TOWARD EVENING.
WILL HANG ONTO SLIGHT CHANCE FOR NOW...BUT IF SOME HIGH RES MODELS
SUCH AS RAP/HRRR TURN OUT TO BE ACCURATE IN THEIR DEPICTION OF DEW
POINTS MIXING MUCH LOWER THAN EXPECTED ACROSS OUR SOUTHEAST THIS
AFTERNOON...THEN CAP WOULD BE STRONGER AND WOULD NOT SEE ANY
DEVELOPMENT. WILL BE SOMETHING TO WATCH THROUGH THE DAY.
LATER TONIGHT...WILL BE LOOKING WESTWARD FOR POTENTIAL OF HIGH PLAINS
CONVECTION TO WORK TOWARD OUR WESTERN COUNTIES. STILL FAIR AMOUNT OF
INSTABILITY FOR STORMS TO WORK WITH AS THEY PUSH TOWARD THE MISSOURI
VALLEY AFTER MIDNIGHT. WILL CONTINUE TO CARRY CHANCE INTO AREAS ALONG
AND WEST OF THE JAMES VALLEY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 430 AM CDT SUN JUL 7 2013
IF STORMS DO WORK INTO THE WEST LATE TONIGHT...SHOULD SEE THEM LINGER
INTO THE MORNING HOURS ACROSS OUR WEST AND WILL HANG ONTO CHANCE WEST
OF I-29 FOR NOW. HOWEVER THIS PERIOD COULD JUST AS LIKELY BE DRY...AS
SOME MODELS INDICATING HIGH PLAINS CONVECTION WILL NOT SURVIVE THIS
FAR EAST. ALL-IN-ALL...LOW CONFIDENCE IN PRECIP CHANCES ACROSS OUR
WEST LATE TONIGHT/MONDAY MORNING. CONFIDENCE SOMEWHAT HIGHER THAT WE
WILL SEE DEVELOPMENT ACROSS OUR SOUTH BY MID-LATE AFTERNOON MONDAY...
AS WARM FRONT LIFTS BACK TO NEAR THE MISSOURI RIVER VALLEY AND MID
LEVEL HEIGHTS COLLAPSE IN ADVANCE OF APPROACHING WAVE. WITH LITTLE
FLOW NEAR THE BOUNDARY...SHOULD CONTINUE TO SEE LOW LEVEL MOISTURE
BUILD AND ENHANCE INSTABILITY. ALSO START TO SEE BETTER DEEP LAYER
SHEAR WORK INTO THE REGION...LOCALLY ENHANCED ALONG THE BOUNDARY. FOR
THIS REASON...MONDAY AFTERNOON/EVENING LOOKS TO HAVE FAIR POTENTIAL
FOR SEVERE STORMS AS WAVE /IN SOME MODELS/ SLIDES NORTHEAST ACROSS
THE FRONTAL BOUNDARY.
EVOLUTION OF PRECIP BEYOND THIS SOMEWHAT MUDDLED BY POTENTIAL FOR
LINGERING OUTFLOW BOUNDARIES...BUT GENERALLY EXPECT MOST MONDAY NIGHT
ACTIVITY TO WORK EAST OF THE FORECAST AREA BY EARLY TUESDAY. COLD
FRONT WILL BE PUSHING SOUTHEAST THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...AND EXPECT STRONG WARMING INTO THE LOWER TO MID 90S IN
THERMAL RIDGE AHEAD OF THE FRONT. HUMIDITY LINGERS AS WELL...WITH DEW
POINTS IN THE LOWER OR EVEN MID 70S POSSIBLE ACROSS MUCH OF THE AREA.
THIS WILL GIVE FRONT PLENTY OF INSTABILITY TO FEED ON...WITH STORM
DEVELOPMENT AIDED BY SOUTHERN EXTENT OF MAIN UPPER TROUGH WORKING
THROUGH THE NORTHERN PLAINS. WITH CURRENT FORECAST SPEED OF TROUGH
AND SURFACE BOUNDARY...STORMS SHOULD CLEAR MOST OF THE AREA BY 00Z
THOUGH WILL HOLD ONTO A CHANCE EAST OF HIGHWAY 60 INTO THE EVENING
SHOULD SYSTEM SLOW DOWN A BIT.
EARLIER PROJECTED DRY AND COOLER DAY FOR WEDNESDAY STILL ON SCHEDULE
BEHIND COLD FRONT...AS HIGH PRESSURE MOVES INTO THE NORTHERN PLAINS.
UPPER RIDGING UNANIMOUSLY PROGGED TO RETURN LATER IN THE WEEK WITH A
SLOW INCREASE IN TEMPERATURES AND HUMIDITY AS SURFACE HIGH MOVES
EAST OF OUR AREA. THE MAIN QUESTION IS HOW LONG IT WILL TAKE FOR A
THUNDERSTORM THREAT TO RETURN. WILL GO WITH A SLIGHT CHANCE
PROJECTED BY GUIDANCE FOR WEDNESDAY NIGHT FAR WEST AS WARM ADVECTION
QUICKLY BEGINS. OTHERWISE IT LOOKS LIKE FRIDAY WILL BE THE RETURN
DAY. THE THREAT MAY THEN DECREASE FOR SATURDAY AS THE UPPER RIDGE
BUILDS INTO OUR AREA. IN ANY EVENT WIDESPREAD PRECIPITATION SEEMS
UNLIKELY WHILE OUR LITTLE SHOT OF RELATIVELY COOL DRY WEATHER IS
FOLLOWED BY ANOTHER WARM UP. HOWEVER IT DOES NOT LOOK LIKE A RETURN
TO LAST SUMMERS HEAT WAVE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1231 PM CDT SUN JUL 7 2013
MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD. MAY SEE A FEW
ISOLATED STORMS FIRE THIS AFTERNOON AND EVENING...GENERALLY IN THE
VICINITY OF INTERSTATE 90 OR NORTH...AND EAST OF INTERSTATE 29. WILL
LEAVE OUT OF TAFS FOR NOW...SINCE COVERAGE IS EXPECTED TO BE
LOW...AND BEST CHANCE IS EAST OF TAF SITES. A FEW SHOWERS AND STORMS
MAY TRY TO MOVE INTO AREAS WEST OF THE JAMES RIVER THIS EVENING INTO
THE OVERNIGHT. BUT THE CHANCE OF THIS IS TOO LOW TO INCLUDE IN THE
KHON TAF AT THIS TIME. BRIEF REDUCTIONS TO MVFR OR IFR WILL BE
POSSIBLE IN ANY THUNDERSTORM. IF SKIES CLEAR TONIGHT...COULD BE SOME
PATCHY AREAS OF MVFR FOG LIKE LAST NIGHT...WILL NOT PUT ANY MENTION
IN THE TAFS FOR NOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...
LONG TERM...
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
344 PM CDT SUN JUL 7 2013
.SHORT TERM...
A FLATTENED AND QUASI-ZONAL UA RIDGE HAS SHIFTED TO THE SOUTHERN
PLAINS...WITH THE CENTER DRAPED FROM THE SOUTHERN PLAINS TO WRN NM.
A PLUME OF PACIFIC MOISTURE CONTINUED TO SPILL ACROSS THE CWA
RESULTING IN FEW-SCT HIGH LEVEL CLOUDINESS. MID-UPPER LEVEL
THICKNESS VALUES ARE SLIGHTER LOWER THAN YESTERDAY DURING THIS
TIME...BUT WARM TEMPS STILL PREVAILED WITH HIGHS IN THE UPPER 80S TO
LOWER 90S ON THE CAPROCK TO LOWER TO MID 90S OFF THE CAPROCK A SFC
TROUGH WAS LOCATED FROM SWRN KS TO SOUTH CENTRAL NM...THOUGH THE
PRESSURE GRADIENT WAS NOT AS STRONG AS PREVIOUS DAYS AND THUS SRLY
WIND SPEEDS WERE NOT OVERLY BREEZY LATE THIS AFTN /10-20 MPH/. THE
CO-EXISTENCE OF THE AFOREMENTIONED SFC TROUGH WITH THE BEST THETA-E
AXIS...IN ADDITION TO OROGRAPHIC INFLUENCES AND DAYTIME
DESTABILIZATION...CAUSED THE DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS ACROSS THE HIGHER MOUNTAINOUS TERRAIN OF ERN NM AND
SERN CO. WITH THE UA RIDGE TAKING UP RESIDENCE ACROSS THE SOUTHERN
PLAINS...STEERING FLOW IS RATHER WEAK WHICH WILL MAKE MOUNTAINOUS
AREA STORMS HARD PRESSED TO REACH THE FA /THIS HAS BEEN THE CASE THE
PAST FEW DAYS/. HOWEVER...A FEW ELEVATED LIGHT SHOWERS HAVE
DEVELOPED ACROSS THE FAR SWRN TEXAS PANHANDLE...COINCIDING WITH
ADEQUATE ALBEIT WEAK MID-LEVEL MOISTURE CONVERGENCE. THE RUC HAS
PICKED UP ON THIS SIGNAL WITH HINTS OF IT EXPANDING TO THE NWRN
ZONES LATER THIS AFTN...BEFORE WANING AOA SUNSET.
THE PLUME OF PACIFIC MOISTURE TRAPPED BENEATH THE RIDGE WILL ENSUE
TONIGHT...ALTHOUGH IT IS PROGGED TO THIN AND BE CONFINED TO THE WRN
PANHANDLES AND FAR NWRN ZONES. MID-LEVEL ASCENT ACROSS THE SAID
AREA ARE NOT THAT IMPRESSIVE...BUT MODELS DO EXHIBIT LIGHT QPF
SIGNALS NEAR THE TX/NM BORDER OR JUST WEST OF THE CWA. DUE TO RECENT
NIGHTS OF NOCTURNAL ACTIVITY...WILL GO AHEAD AND RAISE POPS TO
MENTIONABLE LEVELS ACROSS THE FAR NWRN ZONES. WEAKENED OVERNIGHT LLJ
EQUATES RELATIVELY LIGHT SERLY SFC WINDS...BUT MILD TEMPS ARE STILL
ANTICIPATED /MID 60S NW TO 70S EAST/. TOMORROW...UA RIDGING AND WARM
TEMPS WILL ENSUE /LOW TO MID 90S ON THE CAPROCK TO MID UPPER 90S OFF
THE CAPROCK/ THOUGH THE CENTER OF THE RIDGE WILL RETROGRADE TO AZ/NM
WHILST A GULF OF MEXICO WEAKNESS TREKS WNW ACROSS SRN TX. NOT
EXPECTING THIS WEAKNESS TO PROVIDE THE CWFA WITH ANY MAJOR CHANGES
WITH REGARD TO SENSIBLE WX...WITH THE EXCEPTION OF DEWPOINTS
INCREASING INTO THE LOW 60S AND NEARING MID-LEVEL CLOUDINESS FOR THE
FAR SERN ZONES. PLUME OF PACIFIC MOISTURE WILL ALSO SHIFT WEST TO
MORE SO ACROSS NM WHERE BEST PRECIP CHANCES WILL RESIDE. /29
&&
.LONG TERM...
FEW CHANGES ONCE AGAIN THIS FORECAST PACKAGE...AS THE LARGE UPPER
LEVEL HIGH PRESSURE RIDGE WILL DOMINATE OUR WEATHER THROUGH THE
WEEK AND LIKELY THE WEEKEND AS WELL. PRECIPITATION SIGNALS THIS
COMING WEEK ARE HARD TO COME BY...THOUGH ONE WE ARE SEEING
CONSISTENTLY IS IN THE LATE WEDNESDAY AND EARLY THURSDAY TIME-
FRAME AS A WAVE DIGS INTO THE NORTHERN GREAT LAKES WITH A
WEAKENING SURFACE FRONTAL BOUNDARY LURCHING SLOWLY SOUTHWARD. THE
LATEST RUNS DO NOT APPEAR TO WEAKEN THE RIDGE VERY MUCH AND
STEERING FLOW SHOULD REMAIN VERY WEAK. BUT SOLUTIONS HAVE BEEN
PAINTING THUNDER DEVELOPMENT NEAR THIS BOUNDARY ACROSS THE TEXAS
PANHANDLE INTO WESTERN OKLAHOMA...AND EVEN VERY NEAR THE RED RIVER
BY EARLY THURSDAY. BULK OF SOLUTIONS...HOWEVER...APPEAR TO BOUND
THE ACTIVITY JUST TO THE NORTH AND EAST OF THE NORTHERN ROLLING
PLAINS. WE WILL RETAIN THE JUST SUB-MENTIONABLE LEVEL OF
PRECIPITATION UNTIL WE SEE MORE SIGNALS WITHIN OUR AREA. FOLLOWING
THIS WAVE...THE UPPER RIDGE STILL APPEARS TO SPRING BACK TO THE
NORTH AND EAST...CENTERED JUST TO OUR NORTH FOR THE END OF THE
WEEK INTO THE EARLY WEEKEND. THIS STILL SHOULD ACCOUNT FOR
SLIGHTLY HOTTER TEMPERATURES AND WE HAVE BOOSTED HIGHS A DEGREE OR
TWO ABOVE THE PREVIOUS FORECAST. FINALLY...BY LATE IN THE WEEKEND
THE RIDGE IS EXPECTED TO RETROGRADE TO OUR WEST AS A SOUTHWESTWARD
MOVING UPPER LOW TRAVERSES THE DEEP SOUTH PERHAPS CROSSING WEST OF
THE MISSISSIPPI BY MONDAY. LOTS OF QUESTIONS ABOUT THIS PATTERN...
THOUGH SOME LEVEL OF COOLING ALONG WITH A MOISTURE INCREASE SEEM
FAIRLY CERTAIN. MOST OF THE REAL CHANGES... HOWEVER...WILL BE IN
DAY 8 AND BEYOND. STAY TUNED. RMCQUEEN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 66 93 67 95 67 / 20 10 10 10 10
TULIA 66 95 69 97 69 / 10 10 10 10 10
PLAINVIEW 67 93 69 96 69 / 10 10 10 10 10
LEVELLAND 67 94 68 94 68 / 10 10 10 10 10
LUBBOCK 69 96 70 96 70 / 10 10 10 10 10
DENVER CITY 68 94 67 93 67 / 10 10 10 10 10
BROWNFIELD 69 94 67 95 68 / 10 10 10 0 10
CHILDRESS 70 98 73 100 74 / 0 0 0 0 10
SPUR 70 97 71 97 71 / 0 0 0 0 10
ASPERMONT 71 98 72 100 73 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29/05
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1242 PM CDT SUN JUL 7 2013
.AVIATION...
WITH OVERALL POP BEING ABOUT 20 PERCENT THIS AFTERNOON ACROSS THE
I-35 CORRIDOR...HAVE REMOVED MENTION OF SH/TS IN THE SHORT TERM IN
THE AUS/SAT/SSF TAFS. SEABREEZE ACTIVITY IS EXPECTED TO FIRE UP
TO THE SOUTHEAST THIS AFTERNOON BUT STILL QUESTIONABLE WHETHER IT
WILL MAKE IT THIS FAR INLAND. SCT CLOUDS EXPECTED ALTHOUGH FOR THE
REMAINDER OF THE AFTERNOON COULD SEE SOME CIG DECKS FROM TIME TO
TIME BUT SHOULD BE AROUND 5KFT OR SO.
WITH PRECIPITABLE WATER INCREASING TO OVER 2 INCHES
TOMORROW...HAVE INPUT SOME VCSH FOR THE MORNING HOURS AND ADDED A
PROB30 GROUP IN THE 30 HOUR TAFS OF AUS/SAT FOR THE POSSIBILITY OF
AFTERNOON SHOWERS AND STORMS. SOME MVFR CIGS ARE ONCE AGAIN
EXPECTED IN THE EARLY-LATE MORNING. CLOUDS SHOULD BE A BIT MORE
NUMEROUS ON MONDAY ESPECIALLY IN THE AFTERNOON WITH THE DEEPER
MOISTURE AND DEBRIS CLOUDS FROM NEARBY CB. LEFT DRT TAF DRY FOR
NOW AS CONFIDENCE IS LOW ON HOW FAR WEST THE MOISTURE WILL PUSH BY
18Z MON. AM THINKING BEST CHANCES FOR DRT WILL OCCUR LATER ON MON
AFTERNOON AND MON NIGHT.
&&
.PREV DISCUSSION... /ISSUED 1051 AM CDT SUN JUL 7 2013/
UPDATE...
MINOR ADJUSTMENTS TO FIRST PERIOD.
DISCUSSION...
MORNING SOUNDINGS INDICATE PW VALUES HAVE INCREASED BY .25 TO .5
INCHES ACROSS THE AREA AS COMPARED TO 24 HRS AGO. MOISTURE WILL
CONTINUE TO INCREASE AS THE UPPER LOW IN THE NWRN GULF PROGRESSES
ONSHORE LATER TODAY. ISOLATED SHOWERS AND THUNDERSTORMS HAVE
PUSHED INTO THE COASTAL PLAINS THIS MORNING...AND SHOULD INCREASE
IN COVERAGE ONCE DIURNAL HEATING BECOMES A FACTOR. ONGOING
FORECAST IS GENERALLY ON TRACK. ONLY MINOR ADJUSTMENTS WERE MADE
TO FIRST-PERIOD POPS/WX/QPF AND TEMPERATURES. NEW ZONES WILL BE
OUT SHORTLY.
PREV DISCUSSION... /ISSUED 641 AM CDT SUN JUL 7 2013/
UPDATE...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
A TROPICAL AIR MASS AND A MOSTLY ELEVATED LOW PRESSURE TROUGH
MOVING INTO THE TX COAST WILL DISRUPT THE OCCASIONAL MVFR CIG THIS
MORNING. WITH LIGHT WINDS AND BUOYANT AIR IN THE AREA...SCT LOW
BASED CUMULUS OF AROUND 1500 FT WILL HAVE TOPS LIFTING TO 10000 FT
OR HIGHER AS LIGHT SHOWERS BEGIN TO MOVE TOWARD THE I-35
TERMINALS. WILL LEAVE OUT MENTION OF MVFR CIGS UNTIL THE BETTER
CHANCE OF RAINS ARRIVE IN THE EARLY AFTERNOON HOURS AS DEPICTED BY
THE HRRR SIMULATED REFLECTIVITY. ANY FEEBLE ATTEMPT TO DEVELOP A
SURFACE CIRCULATION EAST OF BRO SHOULD BE HELD IN CHECK AS THE
UPPER SUPPORT PUSHES ONSHORE BY TONIGHT. THUS WILL PLAN ON A MORE
STEADY ONSHORE WIND BY TONIGHT...AND A MORE ROUTINE FORMATION OF
LOW CLOUDS AT AROUND 09Z. HIGH PWAT VALUES COULD SUPPORT
ADDITIONAL SHOWERS AROUND DAYBREAK...BUT WILL LEAVE OUT OF THE
LATE PERIODS OF THE TAFS UNTIL A BETTER TREND CAN BE ESTABLISHED.
PREV DISCUSSION... /ISSUED 322 AM CDT SUN JUL 7 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
A WEAKENED UPPER LEVEL INVERTED TROUGH FEATURE OVER THE WESTERN GULF
OF MEXICO WILL MIGRATE WEST ONTO THE TEXAS COASTAL PLAINS REGION
TODAY WITH AN ENHANCEMENT OF SEA BREEZE ACTIVITY LIKELY OVER
SOUTHERN AND EASTERN PORTIONS OF THE CWA. HIGH TEMPERATURES TODAY
WILL LOWER SLIGHTLY WITH THE INCREASING SURFACE BASED MOISTURE.
HIGHS TODAY WILL RANGE FROM THE LOW 90S ACROSS PORTIONS OF THE HILL
COUNTRY TO THE MID TO UPPER 90S ELSEWHERE. INCREASING CLOUDINESS
TONIGHT WITH A SLIGHT CHANCE OF MOSTLY EARLY EVENING SHOWERS AND
STORMS SOUTH AND EAST. LOWS IN THE 70S. THE UPPER TROUGH WILL MOVE
ACROSS THE AREA MONDAY WITH DEEP...MOIST TROPICAL EASTERLIES
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGHOUT MUCH OF
THE AREA. HIGHS MONDAY WILL MODERATE BACK INTO THE LOWER 90S MOST
LOCATIONS WITH NEAR 90 HILL COUNTRY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
SHOWERS AND STORMS WILL DIMINISH MONDAY EVENING AS THE INVERTED
UPPER TROUGH PUSHES DEEPER INTO MEXICO. LOWS MONDAY NIGHT AGAIN
MOSTLY IN THE 70S WITH NEAR 70 HILLS. UPPER LEVEL RIDGING WILL BUILD
BACK OVER THE REGION TUESDAY AND REMAIN STRONG THROUGH SATURDAY AS
THE CENTER OF THE HIGH SHIFTS EAST INTO THE SOUTHERN PLAINS BY LATE
IN THE WEEK. CONTINUED DEEP EASTERLIES HOWEVER IN THE MID AND LOWER
LEVELS OF THE ATMOSPHERE WILL ENHANCE SOME SEA BREEZE CONVECTION
INTO EASTERN SECTIONS BOTH TUESDAY AND WEDNESDAY. MORNING LOW CLOUDS
WILL BECOME PARTLY CLOUDY AFTERNOONS BOTH DAYS WITH HIGHS RANGING
FROM THE LOW 90S HILLS TO THE UPPER 90S TO NEAR 100 EASTERN SECTIONS.
LOWS IN THE 70S. ANOTHER EASTERLY WAVE FEATURE PUSHING ACROSS THE
COASTAL PLAINS THURSDAY WILL GENERATE MORE ACTIVITY OVER EASTERN
SECTIONS BOTH THURSDAY AND FRIDAY. HIGHS WILL CONTINUE NEAR OR
SLIGHTLY ABOVE SEASONAL NORMS THURSDAY THROUGH SATURDAY. LOWS
GENERALLY IN THE 70S EXCEPT UPPER 60S TO NEAR 70 HILLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 97 75 94 74 100 / 20 20 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 96 74 93 72 99 / 20 20 30 10 -
NEW BRAUNFELS MUNI AIRPORT 95 73 93 72 96 / 20 20 30 10 10
BURNET MUNI AIRPORT 94 74 91 73 96 / 10 10 20 10 -
DEL RIO INTL AIRPORT 97 76 92 75 94 / - - 30 20 10
GEORGETOWN MUNI AIRPORT 95 74 93 72 98 / 20 10 20 10 -
HONDO MUNI AIRPORT 96 74 90 73 96 / 20 10 30 20 -
SAN MARCOS MUNI AIRPORT 96 74 93 73 97 / 20 20 30 10 10
LA GRANGE - FAYETTE REGIONAL 94 76 92 75 99 / 40 20 30 10 20
SAN ANTONIO INTL AIRPORT 94 76 91 75 96 / 20 20 30 10 -
STINSON MUNI AIRPORT 95 74 92 73 94 / 20 20 30 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...25
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1221 PM CDT SUN JUL 7 2013
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD. SLIGHTLY
BREEZY SRLY WINDS /10-12 KTS/ WILL DECLINE FURTHER SHORTLY AFTER
SUNSET. FEW-SCT CLOUD DECKS THIS AFTN WILL BECOME SKC OVERNIGHT
THROUGH TOMORROW.
&&
PREV DISCUSSION... /ISSUED 343 AM CDT SUN JUL 7 2013/
SHORT TERM...
DIRTY SOUTHWESTERN RIDGE HAS EXPANDED TO ENCOMPASS WEST TEXAS AND
THIS WILL PROVIDE ANOTHER TOASTY JULY DAY WITH HIGHS SIMILAR TO
SATURDAY. MID-LEVEL MOISTURE SPILLING OVER THE SOUTH PLAINS COUPLED
WITH WEAK ELEVATED INSTABILITY...DEEP LAYER MOISTURE CONVERGENCE AND
ELEVATED FRONTOGENESIS WERE SUPPORTING A FEW RECENTLY DEVELOPED
SHOWERS AND STORMS ACROSS THE FAR NORTHWESTERN ZONES. THIS ACTIVITY
WAS NOT MOVING MUCH THANKS TO WEAK STEERING FLOW/WINDS WITHIN THE
RIDGE...BUT WE COULD SEE AT LEAST ISOLATED ACTIVITY HANG ON ACROSS
THE WESTERN ZONES AND PERHAPS EXPAND/DEVELOP TOWARD THE I-27/US-87
CORRIDOR AS THE RECENT RAP AND HRRR RUNS SUGGEST. HENCE HAVE
INSERTED A SLIGHT CHANCE OF THUNDERSTORMS INTO THE GRIDS ACROSS THE
WESTERN AND INTO THE CENTRAL ZONES IN THE 12-18Z TIME-FRAME. ANY
ACTIVITY WILL LIKELY WANE TOWARD MID TO LATE MORNING. STRONG HEATING
AND SUFFICIENT MOISTURE WILL THEN YIELD ANOTHER ROUND OF CONVECTION
OVER THE HIGHER TERRAIN OF NM AND CO THIS AFTERNOON...BUT SIMILAR TO
SATURDAY...THIS ACTIVITY WILL NOT HAVE MUCH INCENTIVE TO MOVE VERY
FAR EASTWARD AND SHOULD STAY WELL WEST OF THE CWA. THE MID-LEVEL
MOISTURE PLUME WILL STILL EXTEND IN CLOSE PROXIMITY TO THE FAR
NORTHWESTERN ZONES LATE TONIGHT AND THERE MAY BE SOME RISK OF LATE
NIGHT ELEVATED CONVECTIVE DEVELOPMENT LIKE WE HAVE SEEN THE LAST
COUPLE OF NIGHTS. HOWEVER THE MID-LEVEL MOISTURE PLUME IS PROGGED TO
THIN/DRY A BIT LOCALLY AND LOW-LEVEL FORCING APPEARS LESS...SO HAVE
KEPT THE FORECAST DRY FOR TONIGHT. OTHERWISE...IT WILL BE ANOTHER
MILD NIGHT WITH LOWS VARYING FROM THE MID-60S NORTHWEST TO LOWER AND
MIDDLE 70S EAST.
LONG TERM...
AN UPPER LEVEL RIDGE...CENTERED ROUGHLY OVER THE 4-CORNERS INITIALLY...
AND GRADUALLY MIGRATING INTO THE CENTRAL HIGH PLAINS...WILL KEEP
THE FA HOT AND DRY FOR THE MOST PART THIS UPCOMING WEEK.
OROGRAPHICALLY FORCED CONVECTION WITHIN MOISTURE PLUME TRAPPED IN
THE RIDGE SHOULD REMAIN TO OUR WEST MONDAY WHILE AN INVERTED
TROUGH MOVING WEST ACROSS THE BIG BEND WILL BE OF LITTLE
CONSEQUENCE TO OUR WX. WE ARE STILL WATCHING FOR A TEMPORARY
WEAKNESS TO DEVELOP IN THE EASTERN PART OF THE RIDGE WED/THU AS A
SHORTWAVE MOVES FROM THE CANADIAN PRAIRIES TO THE GREAT LAKES AND
A COLD FRONT DIPS INTO SRN CO/SW KS. BUT ANY TSTM ACTIVITY
ASSOCIATED WITH THIS WAVE/FRONT APPEARS UNLIKELY TO MAKE IT INTO
OUR NRN ZONES LATE WED/EARLY THU. THEN...AS THE UPPER RIDGE RE-
EXPANDS E-NEWD WE EXPECT TEMPS TO NUDGE UPWARD A FEW DEGREES
HEADING INTO NEXT WEEKEND. EARLY NEXT WEEK...THE UPPER RIDGE MAY
START TO RETROGRADE BACK TO THE WEST AS AN UPPER TROUGH/LOW
DEVELOPS IN THE DEEP SOUTH. WE ARE COUNTING ON THIS PATTERN CHANGE
TO BRING A COOLING TREND AND PERHAPS A CHANCE OF RAIN NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 66 93 66 95 67 / 10 10 10 10 10
TULIA 67 95 68 96 69 / 10 10 10 10 10
PLAINVIEW 67 95 69 95 69 / 10 10 10 10 10
LEVELLAND 68 94 70 94 69 / 10 10 10 10 10
LUBBOCK 70 95 70 95 71 / 10 10 10 10 10
DENVER CITY 68 93 69 93 67 / 10 10 10 10 10
BROWNFIELD 69 94 70 95 69 / 10 10 10 0 10
CHILDRESS 71 98 74 99 75 / 0 0 0 0 10
SPUR 71 96 72 97 72 / 0 0 0 0 10
ASPERMONT 72 97 74 99 75 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1043 AM PDT Sun Jul 7 2013
.SYNOPSIS...
There will be a chance for thunderstorms over the North Cascades
this afternoon with the remainder of the region generally warm and
dry. The threat for showers and thunderstorms will migrate east
overnight into portions of Eastern WA and into the Idaho Panhandle
on Monday. Tuesday and Wednesday should be the warmest days of the
week with continued dry conditions. Wednesday will be locally
breezy...especially in and near the Cascades with the arrival of a
cold front late. The front could knock temperatures back close to
normal for Thursday, Friday, and Saturday.
&&
.DISCUSSION...
Surface-based cumulus are starting to develop over the ridges of
the north Cascades. Still too shallow to see anything on radar.
15Z HRRR still shows stronger convection developing in the next
few hours, which is in line with the current forecast.
As the short wave responsible for this convection tracks eastward
across our area, the showers/thunderstorms will move across the
northern mountain areas overnight. Could see a stray shower over
the Basin north of Highway 2, including the Spokane/CdA metro area.
Meanwhile another area of thunderstorms will develop tonight after
midnight over southeast WA and the southern Panhandle. This
activity will stay south of the I-90 corridor overnight and into
Monday morning. RJ
&&
.AVIATION...
18Z TAFS: Thunderstorms are expected to develop over the Cascades
this afternoon and may affect the KEAT TAF site around 00Z today.
These showers/thunderstorms will track across the northern
mountains overnight and into the northern Panhandle. There is a
very low probability that they may bring a light shower to the
KGEG/KSFF/KCOE TAF sites late tonight, but the probability was too
low to include in the TAF. Meanwhile to the south thunderstorms
may develop over the Blue Mtns this afternoon/evening but this is
a low probability event. A much better chance of thunderstorms
will occur later tonight from the Blue Mtns across the southern
Idaho Panhandle. These should move east of the area by mid-morning
Monday. RJ
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 85 58 84 58 88 60 / 0 10 20 0 0 0
Coeur d`Alene 84 56 82 54 86 58 / 0 10 20 10 0 0
Pullman 83 53 82 50 88 55 / 0 10 10 0 0 0
Lewiston 92 62 90 60 95 64 / 0 20 10 0 0 0
Colville 88 53 86 52 91 56 / 10 30 50 10 0 0
Sandpoint 83 51 79 49 85 53 / 0 10 50 20 0 0
Kellogg 83 55 80 54 87 57 / 0 10 20 10 0 0
Moses Lake 91 60 90 59 94 62 / 0 10 0 0 0 0
Wenatchee 89 62 89 63 92 65 / 10 20 0 0 0 0
Omak 89 58 89 58 93 60 / 10 20 10 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
305 PM CDT SUN JUL 7 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 305 PM CDT SUN JUL 7 2013
THE MAIN FOCUS GOING INTO TOMORROW IS WITH THE CHANCES FOR RAIN
SHOWERS/THUNDERSTORMS AS A COLD FRONT MOVES THROUGH THE REGION.
CURRENTLY...A HUMID AIR MASS IS IN PLACE AT THE SURFACE AS DEW
POINTS CONTINUE TO RISE IN RESPONSE TO AN INCREASE OF LOW LEVEL
MOISTURE TRANSPORT OUT OF THE GULF. SURFACE ANALYSIS SHOWS TWO
COLD FRONTS IN THE VICINITY OF WESTERN MINNESOTA. THE FIRST ONE
EXTENDS FROM NORTHERN WISCONSIN DOWN THROUGH SOUTH CENTRAL
MINNESOTA AND EASTERN NEBRASKA. THE SECOND COLD FRONT IS JUST TO
THE WEST OF THIS OTHER FRONT AND EXTENDS FROM A SURFACE LOW IN
SOUTHERN MANITOBA DOWN THROUGH WESTERN MINNESOTA AND EASTERN SOUTH
DAKOTA. WITH DEW POINTS IN THE LOW 70S BETWEEN THESE TWO
FRONTS...07.19Z RAP ANALYSIS SHOWS AN AXIS OF 3000 J/KG OF SURFACE
BASED CAPE. CONVECTION HAS INITIATED ALONG THE FIRST FRONT AND A
LAKE BREEZE BOUNDARY NORTHWEST OF THE TWIN CITES AND DOWN ALONG
THE FRONT. FURTHER ALOFT...MID LEVEL RIDGING EXTENDS FROM THE
SOUTHERN PLAINS THROUGH THE UPPER GREAT LAKES. A MID LEVEL SHORT
WAVE TROUGH IS CURRENT IN THE DAKOTAS AND WILL TRACK TO THE EAST
THROUGH TONIGHT AND IS TIED TO THE SECONDARY COLD FRONT.
THE ENVIRONMENT AHEAD OF THE COLD FRONTS APPEARS TO BE CAPPED
AROUND 800MB...SO AM NOT EXPECTING ANY DEVELOPMENT OUT IN THE WARM
SECTOR DESPITE THE HIGH CAPE ENVIRONMENT. THE MAIN CHANCES WILL
BE AS THE FRONT AND WEAKENING MID LEVEL TROUGH COME THROUGH THIS
EVENING AND OVERNIGHT. THE FRONT WILL THEN PUSH THROUGH AND STALL
TO THE SOUTH OF THE REGION IN IOWA ON MONDAY. HAVE DROPPED THE
PRECIPITATION CHANCES DOWN A LITTLE ON MONDAY AS IT LOOKS LIKE
SURFACE TO UPPER LEVEL RIDGING WILL SETTLE IN FOR A BRIEF PERIOD
AND KEEP THE REGION MORE ON THE DRY SIDE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM CDT SUN JUL 7 2013
THE MAIN FOCUS IN THE LONG TERM IS ON MONDAY NIGHT INTO TUESDAY
AND WITH WHERE A MESOSCALE CONVECTIVE SYSTEM WILL DEVELOP AND
TRACK THROUGH ON TUESDAY MORNING.
THE 07.12Z GUIDANCE CONTINUES TO GIVE SOME UNCERTAINTY WITH THE
TRAJECTORY OF THIS MCS. THE GFS/NAM TAKE A MORE SOUTHERLY ROUTE
ACROSS IOWA DUE TO THE LOW LEVEL JET/MOISTURE TRANSPORT ONLY
REACHING EASTERN NEBRASKA BY 6Z TUESDAY. THE PERFERRED GUIDANCE IS
FROM THE ECMWF/GEM SOLUTION WHICH PUSH THE LLJ NOSE INTO EASTERN
SOUTH DAKOTA BY THIS TIME...AND DESPITE THE GEM/ECMWF SHOWING THE
MAIN QPF STAYING WELL TO THE NORTH OF THE REGION TOWARD
DULUTH...AM CONCERNED THAT THE MCS WOULD DEVELOP IN WESTERN
MINNESOTA AND RUN EAST SOUTHEAST ALONG THE NOSE OF THE LOW LEVEL
JET AND INSTABILITY GRADIENT. THIS IDEA FOLLOWS WELL WITH FORECAST
CORFIDI VECTORS WHICH POINT TO THE SOUTHEAST TUESDAY
MORNING...WHICH WOULD TAKE IT STRAIGHT THROUGH THE MIDDLE OF THE
FORECAST AREA ALONG THE MINNESOTA/IOWA BORDER INTO WESTERN
WISCONSIN. GIVEN THE MODEL DIFFERENCES...HAVE NOT HIT THE
PRECIPITATION CHANCES TOO HIGH YET AND WILL HAVE TO SEE HOW THE
PATTERN EVOLVES INTO TOMORROW. WITH THE INCREASING MOISTURE
TRANSPORT AND POTENTIAL FOR HEAVY RAIN...FLASH FLOODING WILL BE A
THREAT DESPITE THE RECENT DRY SPELL. DETAILS ARE OUTLINED IN THE
HYDROLOGY AFD SECTION.
THIS MCS CAUSES SOME HAVOC GOING INTO THE AFTERNOON ON TUESDAY
AND WHAT THE SEVERE THUNDERSTORM CHANCES ARE AFTER ITS PASSAGE. IF
THE SYSTEM TRACKS TO THE SOUTH...THEN IT LIKELY KEEPS THE MAIN
WARM FRONT DOWN THERE AS WELL AND LIMITS THE SEVERE POTENTIAL. IF
IT TRACKS THROUGH THE HEART OF THE FORECAST AREA...AS WE THINK IT
MAY...THE QUESTION WILL BE HOW FAST DOES IT CLEAR AND ALLOW THE
ENVIRONMENT TO RECHARGE BY PEAK HEATING. IF THE SYSTEM WERE TO
CLEAR EARLY ENOUGH AND ALLOW FOR DESTABILIZATION BY LATE AFTERNOON
OUR SEVERE THREAT WOULD BE FAIRLY HIGH DUE TO A VEERING 0-6KM
SHEAR PROFILE...HIGH INSTABILITY...AND DEEP FORCING FROM A SURFACE
LOW AND MID LEVEL TROUGH. WITH A LINGERING OUTFLOW BOUNDARY/WARM
FRONT IN THE REGION...THE HAZARDS WOULD INCLUDE LARGE
HAIL...FLASH FLOODING...DAMAGING WINDS AND THE POSSIBILITY OF A
TORNADO OR TWO GIVEN THE HIGH 0-1KM SHEAR/HELICITY. THE THING
IS...CONFIDENCE IS JUST NOT THERE YET TO LEAN ONE WAY OR ANOTHER
UNTIL THERE IS BETTER CONCENSUS ON THE TRACK OF THE EARLY MORNING
MCS.
BEYOND THIS SYSTEM...IT LOOKS LIKE A DRY AND SEASONAL PERIOD
THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING SETS UP ACROSS
THE UPPER MISSISSIPPI RIVER VALLEY. A COLD FRONT WILL APPROACH THE
REGION FROM THE WEST BY NEXT WEEKEND AND COULD BRING THE NEXT SHOT
OF RAIN ALONG WITH IT. THERE ARE SOME TIMING DIFFERENCES BETWEEN
THE 07.12Z GFS AND ECWMF WITH THIS FEATURE THAT WILL BE RUNNING
INTO THE RIDGING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 1238 PM CDT SUN JUL 7 2013
AT MID DAY A TROUGH/FRONTAL BOUNDARY REMAINED WELL NORTHWEST OF THE
FCST AREA. A MOIST/UNSTABLE AIR MASS WAS IN PLACE ALONG/AHEAD OF THE
FRONT...WITH THE STRONGEST INSTABILITY NEAR THE FRONT. GENERALLY
GOOD VFR EXPECTED THIS AFTERNOON...BUT SOME MOISTURE TRANSPORT INTO
THE AREA AHEAD OF THE FRONT MAY GENERATE WDLY SCT SHRA/TSRA IN/
AROUND THE AREA LATER THIS AFTERNOON INTO THE EVENING. WITH LOWER
CONFIDENCE IN THE CONVECTION CHANCES/COVERAGE THIS AFTERNOON...ONLY
CARRIED A VCSH IN THE TAFS FROM 21-03Z FOR NOW.
THE TROUGH/FRONT LOOKS TO SLIDE THRU THE AREA LATE THIS EVENING INTO
THE OVERNIGHT HOURS. SHRA/TSRA CHANCES APPEAR QUITE LIMITED ONCE THE
BOUNDARY PASSES. HOWEVER WITH WEAK PRESSURE GRADIENTS AND THE MOIST
LOW LEVEL AIR MASS OVER THE AREA...LATE NIGHT/EARLY MORNING
RADIATIONAL BR/FG BECOMES A CONCERN AT BOTH TAF SITES. UNTIL DETAILS
BECOME CLEARER...CONTINUED THE MVFR/IFR BR MENTION AT BOTH SITES IN
THE 09Z-13Z TIME-FRAME. LOWER LEVEL MOISTURE LINGERS OVER THE AREA
BEHIND THE FRONT ON MON...WITH SOME CUMULUS IN THE 3K-4K FT RANGE
EXPECTED.
&&
.HYDROLOGY...TUESDAY
ISSUED AT 305 PM CDT SUN JUL 7 2013
THE MAIN HYDRO CONCERNS COME IN ON TUESDAY AS A COMPLEX OF
THUNDERSTORMS IS FORECAST TO TRACK THROUGH THE REGION. THE
QUESTION IS WHERE AND WHEN WILL IT COME THROUGH? MOST OF THE MODEL
GUIDANCE SUGGEST THAT THIS SYSTEM WILL FORM IN NORTHWEST NEBRASKA
AND RUN EAST ACROSS IOWA MONDAY NIGHT INTO TUESDAY MORNING. WITH
SHOWERS AND THUNDERSTORMS EXPECTED TO DEVELOP AHEAD OF THIS
COMPLEX NORTH OF A WARM FRONT...THE POTENTIAL IS THERE FOR SOME
HEAVY RAIN TO FALL. THANKFULLY...CONDITIONS HAVE BEEN DRY FOR THE
PAST WEEK...SO FLASH FLOOD GUIDANCE HAS COME UP CONSIDERABLY AND
THE SOIL SHOULD BE ABLE TO HANDLE THE EXCESS MOISTURE REASONABLY
WELL FOR A PERIOD. THAT SAID...INCREASING PRECIPITABLE WATER
VALUES AND LOW LEVEL MOISTURE TRANSPORT AIMING INTO THE
REGION...EXPECT THAT HEAVY RAIN AND FLASH FLOODING IS POSSIBLE
WITH SOME RENEWED RISES ON AREA RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RRS
HYDROLOGY...HALBACH