Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/24/15
AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 AM MST TUE SEP 22 2015
.SYNOPSIS...EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
TODAY FOLLOWED BY A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
NEAR THE MOUNTAINS EAST OF TUCSON WEDNESDAY. DRY CONDITIONS WITH
ABOVE NORMAL DAYTIME TEMPERATURES WILL THEN PREVAIL THURSDAY INTO
EARLY NEXT WEEK.
&&
.DISCUSSION...LATEST SATELLITE IMAGERY AND SURFACE OBSERVATIONS
CONTINUE TO INDICATE BROKEN/OVERCAST CONDITIONS ACROSS MUCH OF
SOUTHEAST ARIZONA EARLY THIS MORNING...WITH SOME CLEARING NOTED OVER
FAR WESTERN PIMA COUNTY IN THE VICINITY OF AJO AND ORGAN PIPE. KEMX
AND AREA RADARS SHOW LIGHT PRECIPITATION PUSHING INTO COCHISE FROM
NORTHERN MEXICO...AS WELL AS A BAND OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS EXTENDING FROM NEAR SANTA ROSA OVER CENTRAL
PIMA COUNTY NORTHEAST THROUGH PINAL COUNTY AND INTO FAR NORTHERN
GRAHAM COUNTY. RADAR PRECIPITATION ESTIMATES FROM THE THUNDERSTORM
NEAR SANTA ROSA OVER THE LAST HOUR WERE BETWEEN 0.50-1.00 INCHES OF
RAINFALL.
ONGOING FORECAST HAS INCREASING PRECIPITATION PROBABILITIES THROUGH
THE MORNING AND INTO THE AFTERNOON...WITH SCATTERED TO NUMEROUS
SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORMS. PLENTIFUL MOISTURE
IN THE LOWER LEVELS...WITH 12Z KTWC SOUNDING INDICATING A PW VALUE
OF 1.40 INCHES AND DEWPOINTS IN THE 60S ACROSS SOUTHERN ARIZONA
ATTM. IN ADDITION...A WEAK UPPER LOW CURRENTLY WEST OF THE NORTHERN
BAJA PENINSULA IS PROGGED TO MOVE NORTHEAST ACROSS CENTRAL ARIZONA
TODAY...RESULTING IN ADDITIONAL LIFT...AS WELL AS SOME COOLING AT
THE MID LEVELS. THE LATEST MODEL RUNS OF THE HRRR AND U OF A WRF-NAM
POINT TO SHOWER/STORM DEVELOPMENT TODAY...CONTINUING THROUGH THE
EVENING HOURS TONIGHT BEFORE DISSIPATING. EXPECT STORMS TO MOVE
RATHER QUICKLY TO THE NORTHEAST WITH THE MODEL SOUNDINGS INDICATING
20-30 KT STEERING FLOW. EVEN WITH DRY AIR ABOVE 500MB...STORM
ENVIRONMENT TODAY WILL SUPPORT SOME STRONG STORMS...PRODUCING BRIEF
HEAVY RAIN...SMALL HAIL AND GUSTY WINDS. HOWEVER...DUE TO THE RATHER
QUICK MOVEMENT OF THE STORMS DO NOT ANTICIPATE WIDESPREAD FLASH
FLOODING ISSUES.
WILL LET THE DENSE FOG ADVISORY FOR PUBLIC ZONES 507 AND 509 (UPPER
SAN PEDRO RIVER AND UPPER GILA RIVER VALLEY/S) EXPIRE AT 9 AM MST.
CURRENT FORECAST PACKAGE IN GOOD SHAPE AND ON TRACK. WILL UPDATE THE
ZONES FOR THE EXPIRATION OF THE DENSE FOG ADVISORY...OTHERWISE NO
ADDITIONAL UPDATES ARE EXPECTED. FOR MORE INFORMATION ON THE LATTER
PERIODS OF THE FORECAST...PLEASE REFER TO PREV DISCUSSION SECTION
BELOW.
&&
.AVIATION...VALID THRU 23/12Z.
SCATTERED TO NUMEROUS -TSRA/-SHRA WILL OCCUR TODAY FOLLOWED BY
ISOLATED TO SCATTERED -TSRA/-SHRA TONIGHT INTO EARLY WEDNESDAY
MORNING. WIND GUSTS GENERALLY OF 30-40 KTS MAY ACCOMPANY THE
STRONGER THUNDERSTORMS THIS AFTERNOON. PATCHY FOG RESTRICTING
VISIBILITIES TO NEAR 1/2SM WILL OCCUR IN THE VALLEYS FROM KTUS
VICINITY EAST AND SOUTH THRU 22/18Z. OTHERWISE...CLOUD DECKS WILL
GENERALLY BE AT 4-7K FT AGL. OCCASIONAL MVFR CONDITIONS ARE
EXPECTED...ESPECIALLY IN THE VICINITY OF KOLS...KDUG AND KSAD.
SURFACE WIND MAINLY BE LESS THAN 10 KTS INTO WEDNESDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL
OCCUR TODAY FOLLOWED BY A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
EAST OF TUCSON WEDNESDAY. DRY CONDITIONS WILL THEN PREVAIL THURSDAY
THROUGH MONDAY. EXPECT LOCALLY GUSTY EAST WINDS FRIDAY INTO SATURDAY.
OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL BE THE RULE WITH ABOVE
NORMAL DAYTIME TEMPERATURES RETURNING THURSDAY AND CONTINUING INTO
EARLY NEXT WEEK.
&&
.PREV DISCUSSION...IR SATELLITE IMAGERY AND SURFACE OBSERVATIONS
INDICATE BROKEN TO OVERCAST LOWER-LEVEL CLOUDS ACROSS SE ARIZONA
EARLY THIS MORNING. AMPLE NEAR-SURFACE MOISTURE WAS IN PLACE WITH
DEWPOINTS MOSTLY IN THE 60S AT THIS TIME. KSAD ASOS HAD RECORDED
VISIBILITIES RANGING FROM 3/4SM TO 3SM DUE TO FOG SINCE 0959Z.
HOWEVER...WATER VAPOR SATELLITE IMAGERY DEPICTED MARKEDLY DRIER
CONDITIONS ALOFT. THIS REGIME WAS VALIDATED VIA THE 22/00Z KTWC
SOUNDING THAT DEPICTED A VERY DRY ENVIRONMENT ABOVE 500 MB.
THE BROAD SCALE UPPER LEVEL PATTERN EARLY THIS MORNING WAS
CHARACTERIZED WITH A WEAK LOW PRESSURE SYSTEM WEST OF NRN BAJA
CALIFORNIA NEAR 29N/119W...AND A NORTH-TO-SOUTH RIDGE AXIS OVER THE
CENTRAL/SRN CONUS PLAINS. FAIRLY FAST SWLY FLOW PREVAILED IN THE MID
AND UPPER LEVELS ACROSS SE ARIZONA.
SCATTERED TO NUMEROUS SHOWERS/TSTMS ARE FORECAST TODAY AS THE
EJECTING/FILLING UPPER LOW INTERACTS WITH THE AMPLE LOWER-LEVEL
MOISTURE. HOWEVER...THE GROWTH POTENTIAL FOR THUNDERSTORMS WILL BE
LIMITED DUE TO THE MARKEDLY DRIER ENVIRONMENT ALOFT. 22/00Z GFS
DEPICTED ONLY VERY MODEST CAPE VALUES TO OCCUR TODAY. THUS...THE
PROSPECT OF STRONG/SEVERE THUNDERSTORMS SHOULD BE MITIGATED.
GIVEN THE LIMITED GROWTH POTENTIAL FOR THUNDERSTORMS...THE FLASH
FLOOD WATCH PREVIOUSLY IN EFFECT FOR MUCH OF THE AREA WAS CANCELLED.
OPTED TO DEPICT PATCHY FOG THIS MORNING IN THE LOWER ELEVATION ZONES
FROM TUCSON EWD/SWD TO THE NEW MEXICO/INTERNATIONAL BORDERS.
SCATTERED SHOWERS/TSTMS ARE EXPECTED THIS EVENING FOLLOWED BY A
SLIGHT CHANCE OF SHOWERS/TSTMS LATE TONIGHT.
DRY CONDITIONS WILL PREVAIL ACROSS MUCH OF THE AREA WED AS THE FLOW
ALOFT BECOMES INCREASINGLY WLY AND SHUNTS THE RELATIVELY DEEPER
MOISTURE EWD INTO THE SRN ROCKIES. THUS...POPS WERE REDUCED WED TO
DEPICT A SLIGHT CHANCE OF SHOWERS/TSTMS ONLY NEAR THE ERN MOUNTAINS.
THEREAFTER...THE 22/00Z GFS/ECMWF/CMC WERE CONSISTENT WITH DEPICTING
AN EXPANSIVE AREA OF HIGH PRESSURE ALOFT TO BE OVER THE SWRN CONUS
THUR-MON.
THE GENERALLY NLY/NELY 700-300 MB FLOW REGIME SHOULD TRANSLATE INTO
AN INCREASINGLY DRIER ENVIRONMENT THIS PERIOD. THUS...HAVE REMOVED
ANY DEPICTION/MENTION OF A SLIGHT CHANCE OF SHOWERS/TSTMS...AND HAVE
OPTED FOR PRECIP-FREE CONDITIONS AREA-WIDE WED NIGHT-MON. LOCALLY
GUSTY EAST SURFACE WINDS SHOULD OCCUR FRI-SAT DUE TO FAIRLY TIGHT
SURFACE PRESSURE GRADIENT.
A PRONOUNCED WARMING TREND WILL OCCUR TODAY-THUR...THEN DAYTIME
TEMPS FRI-MON ARE FORECAST TO AVERAGE A FEW DEGS ABOVE NORMAL.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
949 PM PDT MON SEP 21 2015
Synopsis...
Cooling trend to near normal temperatures through Wednesday as high
pressure weakens over the area. The dry weather will continue
although relative humidity levels will gradually improve. High
pressure will rebuild leading to a warming trend Thursday and
Friday. Normal to below normal temperatures expected this weekend
and into early next week with a chance of showers over the northern
mountains.
&&
*** Corrected record information for Travis AFB ***
.Discussion...
Record breaking high temperatures today for Stockton Airport at
102 degrees breaking the old record of 101 in 1949...Sac Exec
Airport also reached 102 with its prior record being 100 in 1987 &
2011. Travis AFB tied its record of 101 set in 1949.
A fairly warm evening with 9 pm valley temperatures still in the
upper 70s to mid 80s. The onshore gradient between SFO-SAC started
to increase after 5 pm, but observations at Travis AFB have only
shown winds between 10-15 mph so far. That hasn`t provided a quick
cool down tonight. However, the HRRR model does show that the
delta winds should pick up overnight so that early morning
temperatures will be upper 50s/low 60s for much of the valley. No
changes needed for the current forecast package. JBB
.Previous Discussion...
Afternoon (21Z) temps were running a couple of degrees warmer
than yesterday and seemed destined to tie/break a couple of
records in the Srn Sac and Nrn SJV...e.g SCK (101 in 1949) and SAC
(100 in 2011)...and it looks as if this occurred at 22z. The NAEFS
mean temps at 1000 mbs were noted from 32-36 deg C over the area
today...but are forecast to cool to 28-32 deg C over the area Tue
afternoon.
Strong high pressure over the area will weaken into mid week as
short-wave energy moves across the PacNW ahead of a digging trough
over the Gulf of AK. To the south...the closed low off the Baja
Coast is forecast to open-up and move NEwd into the Desert SW the
next couple of days. Moisture and instability from this feature will
remain well south of our CWA...south of Yosemite NP...due to the
trof moving across the PacNW. Cooling is expected to spread inland
across NorCal the next couple of days from a combination of
increased onshore flow and some synoptic cooling from the weakening
ridge. A strong Delta Breeze should promote double digit cooling
through the Carquinez Strait and into the Srn Sac Valley on Tue as
max temps return to near normal for the next couple of days.
Marine layer is well mixed out along the coast and is not likely to
reform in time for a stratus intrusion Tue morning. But perhaps Wed
morning should the ML deepen sufficiently.
Warmer temperatures should return to the region on Thu/Fri as high
pressure builds over the area as the upstream trough deepens over
the eastern Pacific along 140W. JHM
.EXTENDED DISCUSSION (Friday THROUGH Monday)
A weak cold front will approach the northwest corner of CA on
Friday. Any precipitation associated with this system should stay
to the northwest of our area. Southwest flow associated with an
approaching trough from the Gulf of Alaska will bring a cooling
trend beginning on Saturday. Temperatures will be slightly below
normal through the extended period. Breezy south westerly winds
will be possible over the mountain ridges on Saturday as the
aforementioned system approaches our CWA. On Sunday night into
Monday, the ECMWF has a defined closed low off the coast of CA
bringing some precipitation chances into far northern CA. However,
the GFS solution keeps the forecast dry. Have kept precipitation
chances low mostly over northern Shasta County. IDM
&&
.AVIATION...
VFR conditions will continue today with light winds. Breezy
southwest winds should pick up on Tuesday as onshore flow
returns. Expect gusty winds up to 30 knots near the Delta and up
to 25 over mountain ridges for Tuesday. IDM
&&
.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
944 PM MDT WED SEP 23 2015
.UPDATE...
ISSUED AT 942 PM MDT WED SEP 23 2015
MAIN CHANGES TO THIS EVENING`S FORECAST PACKAGE INCLUDE ADDING
AREAS OF LOW CLOUDS AND PATCHY/AREAS OF FOG ON THE PLAINS LATE
TONIGHT THROUGH AT LEAST EARLY THURSDAY MORNING. SHOULD SEE LOW
CLOUDS/PATCHY FOG FORMING FIRST ALONG THE SOUTH PLATTE AROUND
GREELEY AND FT MORGAN WHERE DEWPTS COULD REMAIN IN THE LOW/MID
50S ALL NIGHT. LAST FEW RUNS OF THE HRRR AND RAP HAVE INDICATED A
NEAR SATURATED BNDRY LAYER FROM GREELEY EASTWARD ALONG THE PLATTE
AFTER 09Z TONIGHT. MODELS ALSO SHOW A WEAK UPVALLEY PUSH OF MOIST
AIR WHICH COULD PUSH THE WESTERN EDGE OF THIS LOW CLOUD COVER AS
FAR WEST AS THE NORTH/NORTHEAST DENVER METRO AREA BY 13Z OR SO.
EXCEPT FOR PERHAPS SOME SHALLOW THIN FOG IN THE VICINITY OF
DIA EARLY MORNING...WILL PROBABLY NOT SEE ANY FOG ELSEWHERE IN
THE METRO AREA...ESPLY ON THE SOUTH AND WEST SIDES WHERE LIGHT
DRAINAGE WINDS WILL PRODUCE GREATER TEMP/DEWPT SPREADS. OTHERWISE...
NO CHANGES PLANNED FOR THE MTN AND HIGH VALLEYS ZONES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 142 PM MDT WED SEP 23 2015
RADAR IS SHOWING A BATCH OF SHOWERS AND THUNDERSTORMS OVER THE
SOUTHERN HALF OF LINCOLN COUNTY RIGHT NOW. THERE ARE ALSO ISOLATED
SHOWERS AND THUNDERSTORMS IN THE MOUNTAINS AND FOOTHILLS. WINDS
ARE PRETTY WEAK OVER MUCH OF THE CWA. MODELS HAVE AN UPPER RIDGE
BUILDING INTO THE FORECAST AREA OVERNIGHT AND THURSDAY WITH VERY
WEAK NORTH TO NORTHWESTERLY FLOW ALOFT. THERE IS WEAK DOWNWARD QG
SYNOPTIC SCALE ENERGY TONIGHT AND THURSDAY. THERE WILL BE PRETTY
WEAK DRAINAGE WINDS TONIGHT...WITH WEAK EASTERLY WINDS ON THURSDAY.
FOR MOISTURE...IT DRIES OUT SIGNIFICANTLY THIS EVENING...HOWEVER
SOME OF THE MODELS HINT AT A BIT OF STRATUS OVER THE EASTERN HALF
OF THE PLAINS TOWARDS FRIDAY MORNING. FOR POPS...WILL USE THE
CURRENT RADAR PICTURES AND EXTRAPOLATE A BIT. ALL THE CONVECTION
SHOULD BE DONE NO LATER THAN 03Z. NO POPS AFTER THAT OR ON DRY
SUBSIDENT THURSDAY. FOR TEMPERATURES...THURSDAY`S HIGHS WILL BE
0-1 C WARMER THAN TODAY`S HIGHS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 142 PM MDT WED SEP 23 2015
AN UPPER LEVEL RIDGE WILL BUILD INTO COLORADO FROM THE
SOUTHWEST...ALLOWING FOR A WARM...DRY AND SUBSIDENT AIRMASS TO
REMAIN IN PLACE THROUGH MONDAY OF NEXT WEEK. A SYSTEM IS STILL
PROGGED TO SLIDE ACROSS NORTHERN UTAH AND INTO WESTERN WY SUNDAY
NIGHT...BUT STILL TOO FAR NORTH AND WEST FOR IMPACT THE CWA. FOR
EARLY NEXT WEEK...THE RIDGE AXIS WILL SHIFT MORE TO THE SOUTH AND
EAST...AS A SYSTEM DROPS OUT OF CANADA. TEMPERATURES WILL DROP A
BIT BUT REMAIN ABOVE NORMAL. SOME MOISTURE WILL SLIP SOUTH AS WELL
SO COULD SEE SLGT CHC OF TSTMS IN THE MTNS AND ALONG THE NORTHERN
BORDER...FOR MONDAY AND TUESDAY. THE TREND FOR COOLER...CLOSER TO
SEASONAL TEMPERATURES ANYWAY...AND MAYBE WETTER WEATHER WILL
OCCUR THROUGH THE MIDDLE OF THE WEEK WITH THE RIDGE TO THE EAST
AND A TROUGH POSSIBLY MOVING OUT OF SOUTHERN IDAHO AND ACROSS
CENTRAL WY.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 942 PM MDT WED SEP 23 2015
VFR CONDITIONS EXIST UNDER A MOST CLEAR SKY AT DENVER AREA
TERMINAL THIS EVENING. HOWEVER LATER TONIGHT...MODELS SHOW A PUSH
OF MOIST AND SLIGHTLY COOLER AIR UPSLOPE INTO NORTHERN PORTIONS
OF THE DENVER METRO AREA BY AROUND 13Z. AT THIS TIME...THE
THICKEST LOW CLOUD COVER SHOULD REMAIN NORTH AND EAST OF THE
METRO AREA. ALTHOUGH DIA COULD SEE A SHORT PERIOD...PERHAPS NO
MORE THAN A COUPLE HOURS...OF ILS/IFR CIGS AFTER 13Z TOMORROW
MORNING. ODDS OF FOG FORMING AT DIA LOOK EVEN LOWER...BUT CAN NOT
RULE OUT ENTIRELY. THUS THE VCFG NOTATION IN THE LATEST DIA TAF.
AFTER 16Z/THURSDAY...SHOULD SEE RAPID IMPROVEMENT/CLEARING AS DRIER
AIR SPREADS SOUTHWARD ALONG THE FRONT RANGE. UNDER A MOSTLY CLEAR
SKY...WINDS SHOULD THEN GRADUALLY TURN NORTHEASTERLY DURING THE
AFTERNOON WITH SPEEDS GENERALLY UNDER 10 KTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BAKER
SHORT TERM...RJK
LONG TERM...COOPER
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
416 AM MDT TUE SEP 22 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 416 AM MDT TUE SEP 22 2015
THE TREND TOWARD LESS RAINFALL THAN ANTICIPATED FOR OUR AREA
CONTINUES WITH THE LATEST MODEL RUNS. ALL MODELS...INCLUDING
HRRR/RAP/NAM/GFS/EC...CONTINUE TO SHOW THE HEAVIEST PRECIP TO
FALL SOUTH AND EAST OF OUR AREA. THE HRRR AND RAP INITIALIZED WELL
SHOWING THE RAINFALL OVER CENTRAL NM YESTERDAY EVENING AND LATEST
GUIDANCE SUGGESTS NO PRECIP FOR SRN VALLEYS UNTIL NOON ONWARDS.
LIKE THE LAST SHIFT...DROPPED POP GRIDS CONSIDERABLY FOR THE AREA
ESPECIALLY UP NORTH WHERE MODELS ARE REALLY NOT LIKING ANY PRECIP
WHATSOEVER. SAN JUANS ARE STILL FAVORED UNDER GIVEN OROGRAPHIC
LIFT AND JET POSITION. IN FACT...LOCATION OF THE JET LOOKS TO BE
THE MAIN CULPRIT FOR THE REVISED FORECAST. PREVIOUS RUNS PLACED
THE JET GENERALLY OVER OUR AREA ALLOWING PLENTY OF UPPER LEVEL
SUPPORT PROVIDING LIFT WHILE THE LOW PRESSURE/TROUGH ALLOWED
MOISTURE TO STREAM INTO OUR AREA. IT APPEARS THE UPPER LEVEL
TROUGH WAS A BIT STRONGER THAN ORIGINALLY ADVERTISED WHICH PUSHED
THE STRONGEST PORTION OF THE JET STREAM FURTHER EAST...THUS LESS
DIVERGENCE AND LIFT. SO WHAT THIS ALL TRANSLATES TO IS MOST OF THE
CWA SEEING INCREASED MID AND HIGH LEVEL CLOUDS WHILE THE SAN JUANS
AND TO A LESSER EXTENT THE SOUTHERN VALLEYS (CORTEZ...DURANGO...
PAGOSA SPRINGS) SEE THE PRECIP.
OVERNIGHT...A FEW SHOWERS WILL CONTINUE OVER THE SAN JUANS...AND
MAYBE A FEW OVER THE CONTINENTAL DIVIDE...BUT THAT SHOULD BE IT
FOR THE REST OF THE CWA. FOR WEDNESDAY...THE GFS SHOWS A FEW
RESIDUAL SHOWERS OVER THE SAN JUANS WHILE THE NAM PAINTS SOME
SHOWERS OVER HIGHER TERRAIN DUE TO SOME INSTABILITY AND DAYTIME
HEATING. EC ALSO SHOWS A DEARTH OF PRECIP SO LEANING IN THAT
DIRECTION WITH GENERALLY SCHC TO CHC FOR THE SAN JUANS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 416 AM MDT TUE SEP 22 2015
SHOWERS DIMINISH WEDNESDAY EVENING AS THE SYSTEM RESPONSIBLE FOR
OUR WEATHER THROUGH THE EARLY PART OF THE WEEK PUSHES EASTWARD
OVER THE SOUTHERN PLAINS. MEDIUM RANGE MODELS ALL SHOWED HIGH
PRESSURE REBUILDING IN ITS WAKE BRINGING A PERIOD OF DRY AND WARM
CONDITIONS WHICH ARE EXPECTED TO PERSIST THROUGH SATURDAY.
THE ECMWF AND GFS DIVERGE SUNDAY AND MONDAY. THE EC SOLUTION
TRANSLATES A SHALLOW SHORTWAVE TROUGH EASTWARD ACROSS THE
NORTHERN ROCKIES DURING THIS PERIOD. THIS FEATURE FLATTENS THE
RIDGE A BIT...BUT OTHERWISE DOES LITTLE TO CHANGE CONDITIONS OVER
THE AREA. IN CONTRAST...THE GFS DEPICTED A DEEPER AND SLOWER SHORT
WAVE TROUGH WHICH CAUSES THE HIGH TO SHIFT EASTWARD. THIS SOLUTION
RESULTS IN BREEZY CONDITIONS ACROSS THE NORTH WITH SHOWERS AND A
FEW THUNDERSTORMS DEVELOPING NORTH OF THE I-70 CORRIDOR SUNDAY
AFTERNOON WHICH WILL CONTINUE OFF AND ON THROUGH MONDAY. WPC
POINTS TO SIGNIFICANT SPREAD IN MODEL ENSEMBLES ON DAYS 6 AND 7 SO
LITTLE CONFIDENCE IN ONE SOLUTION OVER THE OTHER. CONSEQUENTLY...
WILL HOLD OFF PUSHING PRECIPITATION CHANCES ONE WAY OR THE OTHER
FOR NOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 416 AM MDT TUE SEP 22 2015
REMNANT TROPICAL MOISTURE WILL MOVE OVER SOUTHWEST COLORADO
BRINGING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO THE SAN
JUAN MOUNTAINS AND ADJACENT LOWER ELEVATIONS TO THE SOUTH THROUGH
18Z. THIS ACTIVITY WILL INCREASE IN COVERAGE AFTER 18Z AND
CONTINUE THROUGH THE EVENING TO 06Z/WED BEFORE DECREASING LATER
TONIGHT. AREAS IMPACTED WILL BE MAINLY SOUTH OF A KU64...KAIB...
KGUC LINE THOUGH THERE WILL BE LOW END SCATTERED SHOWER/TSTORM
COVERAGE OVER THE CENTRAL COLORADO MOUNTAINS. KCEZ...KDRO AND
KPSO ARE LIKELY TO EXPERIENCE PERIODS OF SHOWERS/THUNDERSTORMS
WHICH COULD BRING CIGS DOWN TO ILS BREAKPOINTS. BRIEF MVFR VSBY IN
HEAVY RAIN IS ALSO POSSIBLE. CHANCES ARE LOWER FOR KTEX AND KGUC
WITH PROBABILITY FOR RAINFALL SIGNIFICANTLY LOWER TO THE NORTH.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...TGR
LONG TERM...NL
AVIATION...NL
WHEN THIS MIGHT OCCUR. BASED IN THE EXTENDED FORECAST DISCUSSION
ISSUED BY THE WEATHER PREDICTION CENTER EARLIER THIS MORNING...THEY
FAVOR A STRONGER HIGH PRESSURE AND A MORE SUPPRESSED PRECIPITATION
SHIELD.
AS FOR TEMPERATURES...EXPECTING NORMAL TO SLIGHTLY ABOVE OVER THE
WEEKEND MODERATING TO ABOVE NORMAL EARLY NEXT WEEK.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
EXPECTING VFR CONDITIONS THROUGH THE TAF PERIOD...12Z/WEDNESDAY.
MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE AREA
THROUGH MUCH OF THE DAY AS A WEAK SHORT WAVE TROUGH MOVES ACROSS
THE REGION. THE CLOUD COVER WILL DECREASE WITH SKIES EXPECTED TO
BECOME CLEAR DURING THE EVENING AS THE TROUGH SHIFTS OFF TO THE
EAST. RIDGING WILL CONTINUE TO DOMINATE AT THE SURFACE. A LIGHT
EASTERLY FLOW WILL DEVELOP TODAY WITH A WINDS BECOMING CALM AGAIN
THIS EVENING.
OUTLOOK...
WED NIGHT-SAT: SOME PATCHY FOG LATE AT NIGHT/EARLY IN THE
MORNING...OTHERWISE NO SIG WX.
&&
.FIRE WEATHER...
DRY WEATHER WILL CONTINUE THROUGH THE NEXT FEW DAYS.
RH VALUES WILL FALL TO 35 TO 50 PERCENT BOTH THIS AFTN AND
TOMORROW AFTN. RH VALUES WILL FALL TO 45 TO 55 PERCENT ON THURSDAY
AFTN. RH VALUES LOOK TO RETURN NEAR 100 PERCENT EACH NIGHT WITH
DEW FORMATION AND FOG FORMATION IN VALLEY AREAS. WINDS WILL BE
LIGHT AND VARIABLE OVER THE NEXT FEW DAYS...GENERALLY 5 MPH OR
LESS.
&&
.HYDROLOGY...
NO HYDROLOGIC CONCERNS THROUGH THE NEXT FIVE DAYS.
AN UPPER LEVEL DISTURBANCE WILL ONLY BRING SOME CLOUDS TO THE
REGION THIS MORNING WITH NO PRECIPITATION EXPECTED.
AFTERWARD...HIGH PRESSURE WILL CONTINUE TO ALLOW FOR DRY WEATHER
THROUGH THE REMAINDER OF THE WEEK.
STREAMFLOW LEVELS OVER EASTERN NY AND WESTERN NEW ENGLAND COMPARED
TO HISTORICAL NORMALS ARE GENERALLY NEAR AVERAGE IN MOST LOCATIONS...WITH
A FEW SPOTS COMING IN AT BELOW NORMAL LEVELS. WITH DRY WEATHER
EXPECTED OVER THE NEXT WEEK...RIVER LEVELS WILL CONTINUE TO REMAIN NEARLY
STEADY OR SLOWLY FALL. A FEW MORE SPOTS MAY BE COMING IN BELOW NORMAL
BY THIS TIME NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MIAMI FL
147 PM EDT TUE SEP 22 2015
.AVIATION...
NOT MUCH CHANGE FROM PREVIOUS THINKING AS AFTERNOON CONVECTION
CONTINUES TO DEVELOP ALONG SEA BREEZE BOUNDARIES WITH MOTION SLOW
AND ERRATIC. THIS WILL MAINTAIN THE POSSIBILITY OF A CELL NEAR
ANY OF THE TERMINALS FOR THE FIRST SEVERAL HOURS WITH MOSTLY VFR
CONDITIONS BUT A BRIEF SUB-VFR CIG/VSBY CANNOT BE RULED OUT. KAPF
IS CURRENTLY 4SM IN TSRA WITH THIS PARTICULAR CELL DRIFTING TO THE
NORTHWEST AND MAY BE POSSIBLE TO END THESE CONDITIONS EARLIER THAN
WHAT IS CURRENTLY IN THE FORECAST. SEA BREEZES WILL BE THE RULE
AGAIN ON WEDNESDAY.
KOB
&&
.PREV DISCUSSION... /ISSUED 1017 AM EDT TUE SEP 22 2015/
UPDATE...
WILL ALTER THE FORECAST SLIGHTLY ON THE MORNING UPDATE BASED ON
MORNING TRENDS. SHOWERS AND THUNDERSTORMS SHOULD GET AN EARLIER
START THAN YESTERDAY DUE TO INCREASED MOISTURE IN THE MID LEVELS
BUT A COUPLE OF SMALL INVERSIONS PERSIST WHICH WILL NO DOUBT
INHIBIT SOMEWHAT STRONGER UPDRAFTS UNTIL THE ATMOSPHERE CAN
OVERCOME THOSE CAPS. STEERING FLOW IS VERY WEAK BUT THE HRRR SHOWS
A SLOW DRIFT TOWARDS THE EAST COAST DURING THE AFTERNOON DUE TO
THE AVERAGE WIND FIELD IS OUT OF THE WEST BUT AT SPEEDS OF MOSTLY
LESS THAN 10 MPH.
KOB
PREV DISCUSSION... /ISSUED 734 AM EDT TUE SEP 22 2015/
AVIATION...
VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH THE FORECAST WITH
SCATTERED CONVECTION DEVELOPING ALONG SEA BREEZE BOUNDARIES. STORM
MOTION WILL BE SLOW AND ERRATIC SO KEPT VCTS IN FOR ALL TERMINALS
AND IT IS POSSIBLE THERE COULD BE BRIEF SUB-VFR CONDITIONS AT ANY
SITE. SURFACE WIND WILL ONCE AGAIN BECOME L/V AFT 00Z THIS
EVENING.
KOB
PREV DISCUSSION... /ISSUED 427 AM EDT TUE SEP 22 2015/
DISCUSSION...
SHORT TERM (TODAY THROUGH THURSDAY)...LINGERING SFC/LOW LEVEL TROUGH
OVER SOUTH FLORIDA EXTENDING WEST FROM LOW PRESSURE OFF THE
CAROLINAS ACTING AS A BOUNDARY OF SORTS, SEPARATING DRIER AIR OVER
AND NORTH OF LAKE OKEECHOBEE AREA FROM HIGHER MOISTURE TO THE SOUTH.
THIS BOUNDARY WILL EVER-SO-SLOWLY DRIFT NORTH OVER THE NEXT FEW DAYS
WHICH WILL LEAD TO DEEPER MOISTURE ALSO SPREADING NORTH OVER THE
ENTIRE AREA. MID/UPPER LEVEL TROUGH WILL DIG SOUTH OVER THE GULF OF
MEXICO DURING THIS TIME AND CONTRIBUTE TO THE MOISTURE INCREASE AS
WELL AS PROVIDE SOME UPPER-LEVEL DIVERGENCE. BY THURSDAY, MOST OF
SOUTH FLORIDA SHOULD HAVE PRECIPITABLE WATER VALUES NEAR OR OVER 2
INCHES.
FOR TODAY, ALTHOUGH HIGHEST POPS WILL AGAIN BE GENERALLY SOUTH OF
ALLIGATOR ALLEY FOLLOWING THE MOISTURE PATTERN, INDICATIONS ARE THAT
THERE WILL BE HIGHER COVERAGE OF AFTERNOON AND EARLY EVENING
SHOWERS/TSTMS COMPARED TO THE PAST TWO DAYS. THEREFORE WILL NUDGE
POPS HIGHER THAN IN PREVIOUS FORECASTS. STEERING FLOW TODAY WILL
BE OUT OF THE NORTH, BUT LIGHT ENOUGH FOR OUTFLOW BOUNDARIES TO
CAUSE CELLS TO PROPAGATE TOWARD THE COASTS. LITTLE CHANGE IN
ATMOSPHERIC INSTABILITY TODAY, WITH A COUPLE OF STRONG STORMS
POSSIBLE BUT NOT OUT OF THE ORDINARY. RAIN CHANCES WILL STAY
RATHER HIGH TONIGHT ALONG THE GULF COAST AND MIA/FTL AREA ALONG
THE EAST COAST AS MID-LEVEL IMPULSE MOVES AROUND THE TROUGH AXIS
IN THE GULF AND ENHANCES SHOWERS/TSTMS. THE GRADUAL UPWARD TREND
IN SHOWERS AND TSTMS CONTINUES WEDNESDAY AND ESPECIALLY ON
THURSDAY AS IMPULSES CONTINUE TO MOVE ACROSS FLORIDA FROM THE
TROUGH STILL OVER THE GULF OF MEXICO. BY THURSDAY, FAIRLY UNIFORM
DISTRIBUTION OF 60/70% POPS AREA-WIDE. INCREASING CLOUDS WEDNESDAY
AND THURSDAY WILL LIMIT INSTABILITY BUT STILL ENOUGH FOR GENERAL
TSTMS ALONG WITH LOCALLY HEAVY RAINFALL.
THE INCREASING CLOUDS WILL ALSO LOWER THE MAX TEMPS FOR WEDNESDAY
AND THURSDAY, WITH TEMPERATURES EXPECTED TO STAY IN THE MID/UPPER
80S. LOWS TONIGHT WILL DIP INTO THE UPPER 60S OVER GLADES COUNTY,
WITH 70S ELSEWHERE...THEN 70S AREA-WIDE THURSDAY AND BEYOND.
LONG TERM (FRIDAY THROUGH MONDAY)...THE MID/UPPER LEVEL TROUGH
WILL FINALLY BEGIN TO MOVE ACROSS THE FLORIDA PENINSULA ON FRIDAY,
WITH ONE MORE DAY OF WIDESPREAD PRECIP. THE WEEKEND RIGHT NOW
LOOKS NOT AS WET AS THE WORK WEEK AS MID/UPPER LEVEL RIDGE BUILDS
INTO SOUTH FLORIDA. PRETTY MUCH TYPICAL LATE SEPTEMBER/RAINY
SEASON POPS FOR THE WEEKEND. MODELS STILL SHOWING LOW PRESSURE IN
THE YUCATAN PENINSULA AREA MOVING INTO THE SOUTHERN GULF OF MEXICO
MONDAY. STILL PLENTY OF TIME TO SEE HOW THIS SYSTEM AFFECTS OUR
WEATHER, IF AT ALL, NEXT WEEK. /MOLLEDA
MARINE...
ASIDE FROM LOCALLY ROUGH CONDITIONS IN SHOWERS AND THUNDERSTORMS,
WINDS WILL BE LIGHT OVER THE LOCAL WATERS. SEAS WILL BUILD TO 4
FEET IN THE GULF STREAM OFF THE BROWARD AND PALM BEACH COUNTY
COASTS WEDNESDAY THROUGH FRIDAY AS A SMALL NORTH SWELL ENTERS THE
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 86 75 88 / 20 40 30 60
FORT LAUDERDALE 76 87 76 88 / 40 50 50 60
MIAMI 75 87 76 87 / 40 50 50 60
NAPLES 74 88 74 88 / 40 40 30 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...10/CD
LONG TERM....10/CD
AVIATION...10/CD
AREA FORECAST DISCUSSION
NWS MIAMI FL
1017 AM EDT TUE SEP 22 2015
.UPDATE...
WILL ALTER THE FORECAST SLIGHTLY ON THE MORNING UPDATE BASED ON
MORNING TRENDS. SHOWERS AND THUNDERSTORMS SHOULD GET AN EARLIER
START THAN YESTERDAY DUE TO INCREASED MOISTURE IN THE MID LEVELS
BUT A COUPLE OF SMALL INVERSIONS PERSIST WHICH WILL NO DOUBT
INHIBIT SOMEWHAT STRONGER UPDRAFTS UNTIL THE ATMOSPHERE CAN
OVERCOME THOSE CAPS. STEERING FLOW IS VERY WEAK BUT THE HRRR SHOWS
A SLOW DRIFT TOWARDS THE EAST COAST DURING THE AFTERNOON DUE TO
THE AVERAGE WIND FIELD IS OUT OF THE WEST BUT AT SPEEDS OF MOSTLY
LESS THAN 10 MPH.
KOB
&&
.PREV DISCUSSION... /ISSUED 734 AM EDT TUE SEP 22 2015/
AVIATION...
VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH THE FORECAST WITH
SCATTERED CONVECTION DEVELOPING ALONG SEA BREEZE BOUNDARIES. STORM
MOTION WILL BE SLOW AND ERRATIC SO KEPT VCTS IN FOR ALL TERMINALS
AND IT IS POSSIBLE THERE COULD BE BRIEF SUB-VFR CONDITIONS AT ANY
SITE. SURFACE WIND WILL ONCE AGAIN BECOME L/V AFT 00Z THIS
EVENING.
KOB
PREV DISCUSSION... /ISSUED 427 AM EDT TUE SEP 22 2015/
DISCUSSION...
SHORT TERM (TODAY THROUGH THURSDAY)...LINGERING SFC/LOW LEVEL TROUGH
OVER SOUTH FLORIDA EXTENDING WEST FROM LOW PRESSURE OFF THE
CAROLINAS ACTING AS A BOUNDARY OF SORTS, SEPARATING DRIER AIR OVER
AND NORTH OF LAKE OKEECHOBEE AREA FROM HIGHER MOISTURE TO THE SOUTH.
THIS BOUNDARY WILL EVER-SO-SLOWLY DRIFT NORTH OVER THE NEXT FEW DAYS
WHICH WILL LEAD TO DEEPER MOISTURE ALSO SPREADING NORTH OVER THE
ENTIRE AREA. MID/UPPER LEVEL TROUGH WILL DIG SOUTH OVER THE GULF OF
MEXICO DURING THIS TIME AND CONTRIBUTE TO THE MOISTURE INCREASE AS
WELL AS PROVIDE SOME UPPER-LEVEL DIVERGENCE. BY THURSDAY, MOST OF
SOUTH FLORIDA SHOULD HAVE PRECIPITABLE WATER VALUES NEAR OR OVER 2
INCHES.
FOR TODAY, ALTHOUGH HIGHEST POPS WILL AGAIN BE GENERALLY SOUTH OF
ALLIGATOR ALLEY FOLLOWING THE MOISTURE PATTERN, INDICATIONS ARE THAT
THERE WILL BE HIGHER COVERAGE OF AFTERNOON AND EARLY EVENING
SHOWERS/TSTMS COMPARED TO THE PAST TWO DAYS. THEREFORE WILL NUDGE
POPS HIGHER THAN IN PREVIOUS FORECASTS. STEERING FLOW TODAY WILL
BE OUT OF THE NORTH, BUT LIGHT ENOUGH FOR OUTFLOW BOUNDARIES TO
CAUSE CELLS TO PROPAGATE TOWARD THE COASTS. LITTLE CHANGE IN
ATMOSPHERIC INSTABILITY TODAY, WITH A COUPLE OF STRONG STORMS
POSSIBLE BUT NOT OUT OF THE ORDINARY. RAIN CHANCES WILL STAY
RATHER HIGH TONIGHT ALONG THE GULF COAST AND MIA/FTL AREA ALONG
THE EAST COAST AS MID-LEVEL IMPULSE MOVES AROUND THE TROUGH AXIS
IN THE GULF AND ENHANCES SHOWERS/TSTMS. THE GRADUAL UPWARD TREND
IN SHOWERS AND TSTMS CONTINUES WEDNESDAY AND ESPECIALLY ON
THURSDAY AS IMPULSES CONTINUE TO MOVE ACROSS FLORIDA FROM THE
TROUGH STILL OVER THE GULF OF MEXICO. BY THURSDAY, FAIRLY UNIFORM
DISTRIBUTION OF 60/70% POPS AREA-WIDE. INCREASING CLOUDS WEDNESDAY
AND THURSDAY WILL LIMIT INSTABILITY BUT STILL ENOUGH FOR GENERAL
TSTMS ALONG WITH LOCALLY HEAVY RAINFALL.
THE INCREASING CLOUDS WILL ALSO LOWER THE MAX TEMPS FOR WEDNESDAY
AND THURSDAY, WITH TEMPERATURES EXPECTED TO STAY IN THE MID/UPPER
80S. LOWS TONIGHT WILL DIP INTO THE UPPER 60S OVER GLADES COUNTY,
WITH 70S ELSEWHERE...THEN 70S AREA-WIDE THURSDAY AND BEYOND.
LONG TERM (FRIDAY THROUGH MONDAY)...THE MID/UPPER LEVEL TROUGH
WILL FINALLY BEGIN TO MOVE ACROSS THE FLORIDA PENINSULA ON FRIDAY,
WITH ONE MORE DAY OF WIDESPREAD PRECIP. THE WEEKEND RIGHT NOW
LOOKS NOT AS WET AS THE WORK WEEK AS MID/UPPER LEVEL RIDGE BUILDS
INTO SOUTH FLORIDA. PRETTY MUCH TYPICAL LATE SEPTEMBER/RAINY
SEASON POPS FOR THE WEEKEND. MODELS STILL SHOWING LOW PRESSURE IN
THE YUCATAN PENINSULA AREA MOVING INTO THE SOUTHERN GULF OF MEXICO
MONDAY. STILL PLENTY OF TIME TO SEE HOW THIS SYSTEM AFFECTS OUR
WEATHER, IF AT ALL, NEXT WEEK. /MOLLEDA
MARINE...
ASIDE FROM LOCALLY ROUGH CONDITIONS IN SHOWERS AND THUNDERSTORMS,
WINDS WILL BE LIGHT OVER THE LOCAL WATERS. SEAS WILL BUILD TO 4
FEET IN THE GULF STREAM OFF THE BROWARD AND PALM BEACH COUNTY
COASTS WEDNESDAY THROUGH FRIDAY AS A SMALL NORTH SWELL ENTERS THE
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 74 86 75 / 30 20 40 30
FORT LAUDERDALE 89 76 87 76 / 40 40 50 50
MIAMI 89 75 87 76 / 50 40 50 50
NAPLES 90 74 88 74 / 40 40 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
651 PM EDT TUE SEP 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH TONIGHT AS WEAK
LOW PRESSURE MEANDERS OFFSHORE. HIGH PRESSURE WILL THEN PREVAIL
INLAND WHILE WEAK LOW PRESSURE AND A COASTAL TROUGH PERSIST INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A WEDGE OF HIGH PRESSURE WILL HOLD FIRM TONIGHT AS LOW PRESSURE
MEANDERS SOUTHEAST OF CAPE HATTERAS. THE REGIME WILL CHANGE LITTLE
OVERNIGHT...ALTHOUGH THE LOW IS FORECAST TO RETROGRADE SLOWLY TO
THE SOUTHWEST. HIGH RESOLUTION MODELS SHOW A SLUG OF MOISTURE
WORKING ITS WAY DOWN THE UPPER SOUTH CAROLINA COAST AFTER
MIDNIGHT AND REACHING THE CHARLESTON TRI-COUNTY AREA AFTER 3-4
AM. ISOLATED SHOWERS WILL BE POSSIBLE IN THIS AREA...INCLUDING THE
CHARLESTON METRO AREA. OTHERWISE...EXPECT DRY CONDITIONS TO
PREVAIL WITH PERHAPS A ROUGE SHOWER MOVING INLAND ALONG THE
BEACHES. LOWS WILL RANGE FROM THE UPPER 60S INLAND TO THE MID 70S
AT THE BEACHES.
THE AUTUMNAL EQUINOX WILL OCCUR AT 421 AM EDT WEDNESDAY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
WEDNESDAY AND WEDNESDAY NIGHT...A WEAK CLOSED UPPER LOW WILL LINGER
NEAR THE FLORIDA PANHANDLE WHILE AN ENTRENCHED COLD AIR DAMMING
REGIME PERSISTS AT THE SURFACE. THE SURFACE LOW OFF THE SC COAST
WILL MEANDER TO THE WEST...BRINGING SLIGHTLY HIGHER RAIN CHANCES TO
COASTAL SECTIONS. GIVEN THE CONSIDERABLE CLOUD COVER EXPECTED TO BE
IN PLACE DURING THE MORNING...HIGH TEMPS WILL BE LIMITED TO THE
LOWER 80S AND INSTABILITY WILL BE MARGINAL. THUS...DESPITE
INCREASING ONSHORE MOISTURE...THERE WILL PROBABLY NOT BE ENOUGH
LIFT FOR SIGNIFICANT RAINFALL INLAND FROM THE COAST.
A RELATIVELY SIMILAR PATTERN WILL PERSIST THURSDAY AND FRIDAY AS THE
UPPER LOW LINGERS OVER WESTERN FLORIDA AND A COASTAL TROUGH PERSISTS
AT THE SURFACE. THE SURFACE LOW IS EXPECTED TO PUSH INTO THE COAST
ON THURSDAY...SPREADING SUBSTANTIAL MOISTURE AND ASCENT INTO
SOUTHERN SC DURING THE DAY. PERSISTENT COLD AIR DAMMING INLAND AND
OVERCAST SKIES WILL KEEP TEMPS FROM RISING ABOVE THE UPPER 70S.
ALTHOUGH THIS WILL SEVERELY LIMIT SURFACE-BASED INSTABILITY...
NEGATIVE SHOWALTER INDICES INDICATE POTENTIAL MID-LEVEL INSTABILITY
SO WE INCLUDED SLIGHT CHANCE THUNDER DURING THE AFTERNOON. WE
MAINTAINED POPS AROUND 50 PERCENT THURSDAY AFTERNOON AND THURSDAY
NIGHT. PRECIP COVERAGE MAY DECREASE A BIT ON FRIDAY AS THE SURFACE
LOW DISSIPATES AND THE COASTAL TROUGH WEAKENS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THROUGH THE LONG TERM PERIOD...THE FORECAST AREA WILL REMAIN IN A
RATHER WEAKLY FORCED PATTERN ALOFT AS THE MID TO LATE WEEK BROAD
UPPER LOW DISSIPATES COMPLETELY. AT THE SURFACE...HIGH PRESSURE WILL
PERSIST AS THE PRIMARY FEATURE OF INTEREST AND THE ADJACENT COASTAL
TROUGH WILL BECOME INCREASINGLY ILL DEFINED THROUGH EARLY NEXT WEEK.
OVERALL CONFIDENCE IN SPECIFIC PERIODS OF RAIN CHANCES ISN/T
PARTICULARLY HIGH...THOUGH THE GENERAL TREND IS DOWNWARD INTO EARLY
NEXT WEEK. POPS HAVE BEEN LIMITED IN THE SLIGHT CHANCE TO CHANCE
RANGE...FAVORING THE COAST AND THE ATLANTIC WATERS. TEMPERATURES ARE
EXPECTED TO REMAIN BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
KCHS...PROBABILITIES ARE INCREASING THAT MVFR CIGS WILL IMPACT THE
TERMINAL ROUGHLY 10-14Z. THERE ARE NO INDICATIONS FOR CIGS
DROPPING TO IFR THRESHOLDS ATTM. EXPECT A RETURN TO VFR BY 14Z
ALTHOUGH MID-LEVEL CIGS WILL HOLD THROUGH THE DAY. GUSTY WINDS
WILL BE POSSIBLE AFTER SUNRISE.
KSAV...THE LATEST MODEL SETS SUGGEST VFR CONDITIONS WILL
PREVAIL...ALTHOUGH CHANCES ARE ABOUT 40-45 PERCENT FOR MVFR CIGS
TO REACH THE TERMINAL 10-14Z. THE LATEST RAP SOUNDINGS SHOW NO
INDICATIONS OF CIGS BELOW 3 KFT ATTM. GUSTY WINDS WILL BE
POSSIBLE AFTER SUNRISE.
EXTENDED AVIATION...CHANCES FOR WIDESPREAD FLIGHT RESTRICTIONS
INCREASE LATE WEDNESDAY NIGHT AND ESPECIALLY THROUGH THE DAY ON
THURSDAY. THESE INCREASED CHANCES WILL LINGER THROUGH THURSDAY
NIGHT AND MUCH OF FRIDAY.
&&
.MARINE...
TONIGHT...A TIGHT PRESSURE GRADIENT BETWEEN AN INLAND WEDGE OF
HIGH PRESSURE AND OFFSHORE LOW PRESSURE WILL MAINTAIN ELEVATED
N/NE WINDS AND SEAS. GUSTS TO 25 KT AND SEAS AS HIGH AS 6-7 FT
JUSTIFY A CONTINUATION OF SMALL CRAFT ADVISORIES FOR AMZ350 AND
AMZ374. ELSEWHERE...CAPPED WINDS AT 15-20 KT AND SEAS 3-5 FT.
WEDNESDAY THROUGH SUNDAY...STARTING ON WEDNESDAY THE LOCAL WATERS
WILL BE POSITIONED BETWEEN INLAND HIGH PRESSURE AND AN AREA OF
OFFSHORE LOW PRESSURE. THE LOW WILL MOVE BACK TO THE WEST TOWARD THE
COAST WEDNESDAY AND WEDNESDAY NIGHT...AND THE NORTHEAST GRADIENT
WILL BECOME ENHANCED. WINDS WILL INCREASE IN RESPONSE TO THE TIGHTER
GRADIENT AND SMALL CRAFT ADVISORIES WILL LIKELY BE NEEDED FOR ALL
THE WATERS AT SOME POINT. WINDS/SEAS ARE EXPECTED TO PEAK LATE
WEDNESDAY NIGHT/THURSDAY MORNING...BEFORE GRADUALLY DIMINISHING
THEREAFTER AS THE LOW WEAKENS AND THE GRADIENT RELAXES. NORTHEAST
FLOW IS EXPECTED TO PREVAIL FROM FRIDAY ONWARD...THOUGH SPEEDS ARE
NOT EXPECTED TO EXCEED 15 KT.
&&
.TIDES/COASTAL FLOODING...
ASTRONOMICAL TIDES WILL BE ON THE INCREASE THIS WEEK INTO THE
WEEKEND DUE TO THE PROXIGEAN SPRING TIDES APPROACHING. WITH THE
EXPECTED EXTENDED PERIOD OF FRESH NORTHEAST WINDS AND LONG
FETCH...IT IS LIKELY WE WILL START APPROACHING COASTAL FLOOD
ADVISORY CRITERIA BY WEDNESDAY OR THURSDAY.
RIP CURRENTS...INCREASING ONSHORE FLOW WITH SOME 9 SEC SWELL AND
ASTRONOMICAL INFLUENCE CREATES A MODERATE RISK FOR RIP CURRENTS ON
WED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THURSDAY FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT THURSDAY FOR AMZ350.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS GOODLAND KS
905 PM MDT WED SEP 23 2015
.UPDATE...
ISSUED AT 850 PM MDT WED SEP 23 2015
REMOVED ANY MENTION OF RAINFALL FROM THE FORECAST UNTIL TOMORROW
AFTERNOON WHEN A BAND OF MOISTURE AND LIFT FROM THE UPPER LEVEL
TROUGH OVER NEBRASKA ROTATE SOUTH OVER GRAHAM AND NORTON COUNTIES.
BETWEEN NOW AND THEN THE ENVIRONMENT WILL BE VERY DRY AND LITTLE
TO NO LIFT. ANY STORMS WHICH DEVELOP SHOULD DO SO JUST EAST OF THE
AREA WHERE THE ENVIRONMENTAL MOISTURE WILL BE BETTER.
ADJUSTED THE PLACEMENT OF THE THICKEST FOG FOR TONIGHT TO MORE
OVER THE WESTERN HALF OR SO OF THE AREA. WOULD NOT BE SURPRISED TO
SEE FOG DEVELOP OVER THE NORTHEAST PART OF THE AREA WHERE THERE
WERE SCATTERED SHOWERS EARLIER THIS EVENING...AS WELL AS OVER THE
SOUTHWEST PART OF THE AREA. MODELS SEEM TO LOOSELY AGREE THE
DENSEST FOG WILL BE WEST OF HIGHWAY 25 AND NORTH OF I-70 WHERE THE
NORTHERLY WINDS WILL BE BRINGING IN MID 50S DEW POINTS FROM
WESTERN NEBRASKA ALONG WITH COOLER AIR. VISIBILITIES AROUND A MILE
OR TWO CAN BE EXPECTED AROUND SUNRISE FOR THIS PART OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 226 PM MDT WED SEP 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CLOSED UPPER LOW MOVING INTO NORTHCENTRAL NEBRASKA...WITH TROUGH
AXIS EXTENDING SOUTH ACROSS OUR CWA INTO SOUTHEAST COLORADO. STRONG
PV HEIGHT ANOMALY IS OVER OUR CWA ASSOCIATED WITH SW QUADRANT OF
CLOSED LOW. CONVERGENCE ALONG SURFACE TROUGH AXIS CURRENTLY SOUTH OF
I-70 AND MID LEVEL ROTATION ALONG SOUTHERN EDGE OF TROUGH HAS AIDED
IN THUNDERSTORM INITIATION ALONG AXIS OF STEEP LAPSE RATES/MODERATE
CAPE.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY WILL CONTINUE TO BE
POSSIBLE ALONG SURFACE TROUGH THIS ACTIVITY...POSSIBLY DEVELOPING
INTO NW KANSAS. HI RES GUIDANCE SHOWS THIS ACTIVITY REMAINING
ROUGHLY ALONG AND SOUTH OF I-70 ALONG TROUGH AXIS. TREND SHOULD BE
FOR THIS ACTIVITY TO TRANSITION TO THE SOUTH AS TROUGH AXIS SLIDES
SOUTH AND LOW LEVEL STABILIZE OVER OUR CWA. SHOWERS/ISOLATED
THUNDERSTORMS IN THE EASTERN CWA MAY CONTINUE TO LINGER THOUGH THE
NIGHT AS MOISTURE/MID LEVEL ENERGY CONTINUES TO ROTATE AROUND THE
MID LEVEL CLOSED LOW IN NEBRASKA. CAPE AXIS OF ROUGHLY 2000 J/KG
WILL SUPPORT SOME STRONGER UPDRAFTS WITH MARGINAL HAIL/WIND THREAT.
SHEAR IS UNIMPRESSIVE WITH EFFECTIVE SHEER BELOW 20KT...SO SEVERE
THREAT IS LIMITED THIS AFTERNOON AND EVENING.
OTHER CONCERN FOR TONIGHT WILL BE POTENTIAL FOR FOG DEVELOPMENT
AS SURFACE HIGH PRESSURE BUILDS IN TO THE WESTERN PART OF OUR CWA
AND SURFACE LOW SHIFTS EAST. WINDS WILL DECREASE BETWEEN THESE
FEATURES AND WITH CLEARING SKIES COMBINE WITH ABUNDANT LOW LEVEL
MOISTURE TO FOR FOG DEVELOPMENT ACROSS AT LEAST THE WESTERN PARTS
OF OUR CWA. CONFIDENCE IN A DENSE FOG EVENT IS LOWERED BY SHIFT IN
WINDS TO THE NW AROUND 12Z...WHICH COULD BRING DRIER AIR AND
BETTER BL MIXING. IN ANY CASE WITH SIGNAL DEPICTED BY SREF
PROBABILITIES AND NAM/RAP CONFIDENCE WAS HIGH ENOUGH TO ADD
PATCHY/AREAS MENTION TO MOST OF CWA.
THURSDAY...AS CLOSED LOW MEANDERS EASTWARD AND MEAN TROUGH AXIS
SHIFTS SOUTHEAST SUBSIDENCE AND A DEEP DRY MID LEVEL AIR MASS
WILL OVERSPREAD OUR CWA. BY LATE THURSDAY AFTERNOON A LOBE OF
VORTICITY MAY ROTATE AROUND BACK EDGE OF CLOSED LOW INTO OUR
CWA. CONSIDERING THE DRY NATURE OF THE AIR MASS...CONFIDENCE IN
MEASURABLE PRECIP WAS TOO LOW TO INCLUDE MENTION THURSDAY
AFTERNOON DESPITE SOME FORCING ALOFT AND STEEP LAPSE RATES. THERE
IS A SPLIT BETWEEN GUIDANCE REGARDING TEMPS AS SOME GUIDANCE SHOWS
REINFORCING CAA BEHIND UPPER LOW OVERSPREADING OUR CWA...WHILE
OTHER GUIDANCE SUPPORTS WAA AND HIGH PRESSURE BEGINNING TO BREAK
DOWN FROM THE WEST. I BUMPED UP TEMPS IN THE WEST (EASTERN
COLORADO) TO THE MID 80S...WITH HIGHS ELSEWHERE GENERALLY IN THE
UPPER 70S/NEAR 80F. THIS ISN`T FAR FROM MOST CONSENSUS SOLUTIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 205 PM MDT WED SEP 23 2015
FORECAST PROBLEMS WILL BE LINGERING CHANCES OF PRECIPITATION INTO
FRIDAY...STRATUS/FOG THURSDAY NIGHT/FRIDAY...AND HOW MUCH DO
TEMPERATURES RECOVER. SATELLITE IS SHOWING AN AMPLIFIED PATTERN OVER
THE PACIFIC WHICH THEN TRANSLATES TO A DEVELOPING TROUGH OVER THE
WESTERN PORTION OF THE COUNTRY THEN A RIDGE BEING PUSHED INTO THE
EASTERN PORTION OF THE COUNTRY.
AT JET LEVEL...THE GFS/CANADIAN/NAM STARTED OUT BEST. AT MID
LEVELS...THE GFS/UKMET/ECMWF WERE DOING A LITTLE BETTER THAN THE
CANADIAN/NAM. THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF ON
THE SURFACE WIND AND PRESSURE FIELD. THE GFS/SREF/CANADIAN WERE
DOING THE BEST ON THE LOW LEVEL THERMAL FIELD.
THURSDAY NIGHT...MODELS VERY SIMILAR TO 24 HOURS AGO. 70H LOW MOVES
TOWARD THE WEST THROUGH THE NIGHT AND IS JUST TO THE EAST/NORTHEAST
OF THE AREA. THE ECMWF IS FURTHER NORTH THAN IT WAS PREVIOUSLY.
NEGATIVE THETA-E LAPSE RATES ARE IN PLACE WITH NOT A LOT BUT
ADEQUATE MID LEVEL MOISTURE. AT THE SAME TIME AS THE LOW MOVES
CLOSER...A SHORTWAVE AND MID LEVEL FRONTOGENESIS ROTATES THROUGH
THE EASTERN THIRD OF THE AREA. MODELS ARE STILL PRODUCING SOME
VERY LIGHT QPF. THINK THERE WILL BE SOME RAINFALL BUT WITH VERY
LIGHT AMOUNTS.
MODELS HAVE ALSO BEEN CONSISTENT FROM YESTERDAY IN BRINGING/INCREASING
LOWER LEVEL MOISTURE ACROSS THE ENTIRE AREA IN THE LAST HALF OF
THE NIGHT. SO HAVE INCREASED CLOUD COVER AND INTRODUCED FOG. IT IS
POSSIBLE THAT COVERAGE COULD BE GREATER WITH DENSE FOG INDICATED.
FRIDAY/FRIDAY NIGHT...EVEN THOUGH 70H LOW WEAKENS...IT CONTINUES
TO DROP SOUTH AND WEST INTO THE FORECAST AREA THROUGH THE DAY. AGAIN
MODELS NOT SHOWING A LOT OF MOISTURE. HOWEVER MODELS...ESPECIALLY
THE ECMWF...IS INDICATING A RATHER STRONG SHORTWAVE TROUGH ROTATING
THROUGH THE AREA. ONCE AGAIN THERE WILL BE NEGATIVE THETA-E LAPSE
RATES IN PLACE ALONG WITH SOME CAPE AROUND. TQ INDEX ALSO INDICATES
INSTABILITY SHOWERS/THUNDERSTORMS POSSIBLE.
LIGHT QPF SHOWN BY OUTPUT AS WELL AS WPC WHICH MATCHES THE ABOVE
REASONING. IT IS POSSIBLE THAT IT COULD END UP BEING SPRINKLES BUT
BELIEVE THERE WILL BE SOME KIND OF SHOWER ACTIVITY AROUND THROUGH
THE AFTERNOON. SO PUT IN A SLIGHT CHANCE OF PRECIPITATION FOR THE
AFTERNOON. MODELS SHOW THE STRATUS AND FOG BURNING OFF BY LATE
MORNING. AM A LITTLE BIT CONCERNED WITH THAT SINCE THE WIND FIELD
WILL REMAIN LIGHT AND SHIFT TO A MORE EASTERLY DIRECTION AS THE DAY
PROGRESSES. WILL END FOG BY MID MORNING BUT STRATUS MAY HOLD ON
LONGER. BECAUSE OF THE CLOUD COVER AND UNFAVORABLE WINDS LOWERED THE
HIGH TEMPERATURES A LITTLE.
AIR MASS LOOKS LIKE IT STABILIZES RAPIDLY LATE IN THE AFTERNOON WITH
THE MAIN LIFT HAVING ALREADY MOVED THROUGH THE AREA. SO FOR NOW
WILL LEAVE THE NIGHTTIME PERIOD DRY WITH HIGH SILENT POPS. IT IS
POSSIBLE THAT SOMETHING COULD BE ONGOING AT THE BEGINNING BUT IT
SHOULD END QUICKLY. RETURN FLOW BEGINS DURING THE NIGHT WITH A
LITTLE MORE WIND EXPECTED WITH THE EAST SEEING THE LEAST AMOUNT.
MODELS NOT AS HIGH WITH THE LOW LEVEL MOISTURE SO WILL LEAVE OUT
ANY MENTION OF FOG FOR NOW.
SATURDAY...RIDGE BUILDS INTO THE AREA WITH INCREASING SOUTHERLY
WINDS AND WARM AIR ADVECTION. THINK SOME OF THE GUIDANCE IS TOO WARM
DUE TO A LACK OF DOWNSLOPE COMPONENT TO THE WIND AND THAT THE FLOW
ALOFT WILL STILL BE OUT OF THE NORTH. ADJUSTED THE MAX TEMPERATURES
DOWN SLIGHTLY...ESPECIALLY FOR THE CENTRAL AND EASTERN PORTIONS.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS STILL SHOWING A LOT OF
DISAGREEMENT IN HOW TO HANDLE THE EASTERN PACIFIC TROUGH AND
WESTERN/CENTRAL RIDGE. THE ECMWF AND CANADIAN ARE STILL THE FURTHEST
WEST AND MORE CUTOFF WITH THE GFS STILL PUSHING THE TROUGH FURTHER
TO THE EAST WHILE RETAINING THE CUTOFF. ALTHOUGH THE GFS IS SLOWER
TODAY THAN YESTERDAY. CONSIDERING THE FLOW PATTERN...CONSISTENT
ECMWF/CANADIAN AND THE SLOWER GFS...THE MORE AMPLIFIED AND SLOWER
SOLUTION LOOKS THE BEST. THE WPC MANUAL PROGS ECHO THIS AS WELL.
SAYING THAT IT LOOKS LIKE DRY AND WARMER WEATHER WILL BE THE
PREVAILING CONDITIONS FOR THIS PERIOD AND LEFT WHAT THE CRH_INIT
GAVE ME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 521 PM MDT WED SEP 23 2015
MVFR TO VFR CONDITIONS WILL PERSIST THROUGH THE FORECAST PERIOD.
KGLD COULD SEE PATCHY FOG AROUND 12Z AND KMCK WILL SEE A REDUCTION
IN CEILINGS WITH SOME LOW STRATUS IN THE 12Z TO 16Z TIME FRAME.
IMPROVED CEILINGS WILL PERSIST THROUGH THE REMAINDER OF THE DAY AT
KMCK HOWEVER PARTLY CLOUDY SKIES WILL CONTINUE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...TL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
528 PM MDT WED SEP 23 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 226 PM MDT WED SEP 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CLOSED UPPER LOW MOVING INTO NORTHCENTRAL NEBRASKA...WITH TROUGH
AXIS EXTENDING SOUTH ACROSS OUR CWA INTO SOUTHEAST COLORADO. STRONG
PV HEIGHT ANOMALY IS OVER OUR CWA ASSOCIATED WITH SW QUADRANT OF
CLOSED LOW. CONVERGENCE ALONG SURFACE TROUGH AXIS CURRENTLY SOUTH OF
I-70 AND MID LEVEL ROTATION ALONG SOUTHERN EDGE OF TROUGH HAS AIDED
IN THUNDERSTORM INITIATION ALONG AXIS OF STEEP LAPSE RATES/MODERATE
CAPE.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY WILL CONTINUE TO BE
POSSIBLE ALONG SURFACE TROUGH THIS ACTIVITY...POSSIBLY DEVELOPING
INTO NW KANSAS. HI RES GUIDANCE SHOWS THIS ACTIVITY REMAINING
ROUGHLY ALONG AND SOUTH OF I-70 ALONG TROUGH AXIS. TREND SHOULD BE
FOR THIS ACTIVITY TO TRANSITION TO THE SOUTH AS TROUGH AXIS SLIDES
SOUTH AND LOW LEVEL STABILIZE OVER OUR CWA. SHOWERS/ISOLATED
THUNDERSTORMS IN THE EASTERN CWA MAY CONTINUE TO LINGER THOUGH THE
NIGHT AS MOISTURE/MID LEVEL ENERGY CONTINUES TO ROTATE AROUND THE
MID LEVEL CLOSED LOW IN NEBRASKA. CAPE AXIS OF ROUGHLY 2000 J/KG
WILL SUPPORT SOME STRONGER UPDRAFTS WITH MARGINAL HAIL/WIND THREAT.
SHEAR IS UNIMPRESSIVE WITH EFFECTIVE SHEER BELOW 20KT...SO SEVERE
THREAT IS LIMITED THIS AFTERNOON AND EVENING.
OTHER CONCERN FOR TONIGHT WILL BE POTENTIAL FOR FOG DEVELOPMENT
AS SURFACE HIGH PRESSURE BUILDS IN TO THE WESTERN PART OF OUR CWA
AND SURFACE LOW SHIFTS EAST. WINDS WILL DECREASE BETWEEN THESE
FEATURES AND WITH CLEARING SKIES COMBINE WITH ABUNDANT LOW LEVEL
MOISTURE TO FOR FOG DEVELOPMENT ACROSS AT LEAST THE WESTERN PARTS
OF OUR CWA. CONFIDENCE IN A DENSE FOG EVENT IS LOWERED BY SHIFT IN
WINDS TO THE NW AROUND 12Z...WHICH COULD BRING DRIER AIR AND
BETTER BL MIXING. IN ANY CASE WITH SIGNAL DEPICTED BY SREF
PROBABILITIES AND NAM/RAP CONFIDENCE WAS HIGH ENOUGH TO ADD
PATCHY/AREAS MENTION TO MOST OF CWA.
THURSDAY...AS CLOSED LOW MEANDERS EASTWARD AND MEAN TROUGH AXIS
SHIFTS SOUTHEAST SUBSIDENCE AND A DEEP DRY MID LEVEL AIR MASS
WILL OVERSPREAD OUR CWA. BY LATE THURSDAY AFTERNOON A LOBE OF
VORTICITY MAY ROTATE AROUND BACK EDGE OF CLOSED LOW INTO OUR
CWA. CONSIDERING THE DRY NATURE OF THE AIR MASS...CONFIDENCE IN
MEASURABLE PRECIP WAS TOO LOW TO INCLUDE MENTION THURSDAY
AFTERNOON DESPITE SOME FORCING ALOFT AND STEEP LAPSE RATES. THERE
IS A SPLIT BETWEEN GUIDANCE REGARDING TEMPS AS SOME GUIDANCE SHOWS
REINFORCING CAA BEHIND UPPER LOW OVERSPREADING OUR CWA...WHILE
OTHER GUIDANCE SUPPORTS WAA AND HIGH PRESSURE BEGINNING TO BREAK
DOWN FROM THE WEST. I BUMPED UP TEMPS IN THE WEST (EASTERN
COLORADO) TO THE MID 80S...WITH HIGHS ELSEWHERE GENERALLY IN THE
UPPER 70S/NEAR 80F. THIS ISN`T FAR FROM MOST CONSENSUS SOLUTIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 205 PM MDT WED SEP 23 2015
FORECAST PROBLEMS WILL BE LINGERING CHANCES OF PRECIPITATION INTO
FRIDAY...STRATUS/FOG THURSDAY NIGHT/FRIDAY...AND HOW MUCH DO
TEMPERATURES RECOVER. SATELLITE IS SHOWING AN AMPLIFIED PATTERN OVER
THE PACIFIC WHICH THEN TRANSLATES TO A DEVELOPING TROUGH OVER THE
WESTERN PORTION OF THE COUNTRY THEN A RIDGE BEING PUSHED INTO THE
EASTERN PORTION OF THE COUNTRY.
AT JET LEVEL...THE GFS/CANADIAN/NAM STARTED OUT BEST. AT MID
LEVELS...THE GFS/UKMET/ECMWF WERE DOING A LITTLE BETTER THAN THE
CANADIAN/NAM. THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF ON
THE SURFACE WIND AND PRESSURE FIELD. THE GFS/SREF/CANADIAN WERE
DOING THE BEST ON THE LOW LEVEL THERMAL FIELD.
THURSDAY NIGHT...MODELS VERY SIMILAR TO 24 HOURS AGO. 70H LOW MOVES
TOWARD THE WEST THROUGH THE NIGHT AND IS JUST TO THE EAST/NORTHEAST
OF THE AREA. THE ECMWF IS FURTHER NORTH THAN IT WAS PREVIOUSLY.
NEGATIVE THETA-E LAPSE RATES ARE IN PLACE WITH NOT A LOT BUT
ADEQUATE MID LEVEL MOISTURE. AT THE SAME TIME AS THE LOW MOVES
CLOSER...A SHORTWAVE AND MID LEVEL FRONTOGENESIS ROTATES THROUGH
THE EASTERN THIRD OF THE AREA. MODELS ARE STILL PRODUCING SOME
VERY LIGHT QPF. THINK THERE WILL BE SOME RAINFALL BUT WITH VERY
LIGHT AMOUNTS.
MODELS HAVE ALSO BEEN CONSISTENT FROM YESTERDAY IN BRINGING/INCREASING
LOWER LEVEL MOISTURE ACROSS THE ENTIRE AREA IN THE LAST HALF OF
THE NIGHT. SO HAVE INCREASED CLOUD COVER AND INTRODUCED FOG. IT IS
POSSIBLE THAT COVERAGE COULD BE GREATER WITH DENSE FOG INDICATED.
FRIDAY/FRIDAY NIGHT...EVEN THOUGH 70H LOW WEAKENS...IT CONTINUES
TO DROP SOUTH AND WEST INTO THE FORECAST AREA THROUGH THE DAY. AGAIN
MODELS NOT SHOWING A LOT OF MOISTURE. HOWEVER MODELS...ESPECIALLY
THE ECMWF...IS INDICATING A RATHER STRONG SHORTWAVE TROUGH ROTATING
THROUGH THE AREA. ONCE AGAIN THERE WILL BE NEGATIVE THETA-E LAPSE
RATES IN PLACE ALONG WITH SOME CAPE AROUND. TQ INDEX ALSO INDICATES
INSTABILITY SHOWERS/THUNDERSTORMS POSSIBLE.
LIGHT QPF SHOWN BY OUTPUT AS WELL AS WPC WHICH MATCHES THE ABOVE
REASONING. IT IS POSSIBLE THAT IT COULD END UP BEING SPRINKLES BUT
BELIEVE THERE WILL BE SOME KIND OF SHOWER ACTIVITY AROUND THROUGH
THE AFTERNOON. SO PUT IN A SLIGHT CHANCE OF PRECIPITATION FOR THE
AFTERNOON. MODELS SHOW THE STRATUS AND FOG BURNING OFF BY LATE
MORNING. AM A LITTLE BIT CONCERNED WITH THAT SINCE THE WIND FIELD
WILL REMAIN LIGHT AND SHIFT TO A MORE EASTERLY DIRECTION AS THE DAY
PROGRESSES. WILL END FOG BY MID MORNING BUT STRATUS MAY HOLD ON
LONGER. BECAUSE OF THE CLOUD COVER AND UNFAVORABLE WINDS LOWERED THE
HIGH TEMPERATURES A LITTLE.
AIR MASS LOOKS LIKE IT STABILIZES RAPIDLY LATE IN THE AFTERNOON WITH
THE MAIN LIFT HAVING ALREADY MOVED THROUGH THE AREA. SO FOR NOW
WILL LEAVE THE NIGHTTIME PERIOD DRY WITH HIGH SILENT POPS. IT IS
POSSIBLE THAT SOMETHING COULD BE ONGOING AT THE BEGINNING BUT IT
SHOULD END QUICKLY. RETURN FLOW BEGINS DURING THE NIGHT WITH A
LITTLE MORE WIND EXPECTED WITH THE EAST SEEING THE LEAST AMOUNT.
MODELS NOT AS HIGH WITH THE LOW LEVEL MOISTURE SO WILL LEAVE OUT
ANY MENTION OF FOG FOR NOW.
SATURDAY...RIDGE BUILDS INTO THE AREA WITH INCREASING SOUTHERLY
WINDS AND WARM AIR ADVECTION. THINK SOME OF THE GUIDANCE IS TOO WARM
DUE TO A LACK OF DOWNSLOPE COMPONENT TO THE WIND AND THAT THE FLOW
ALOFT WILL STILL BE OUT OF THE NORTH. ADJUSTED THE MAX TEMPERATURES
DOWN SLIGHTLY...ESPECIALLY FOR THE CENTRAL AND EASTERN PORTIONS.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS STILL SHOWING A LOT OF
DISAGREEMENT IN HOW TO HANDLE THE EASTERN PACIFIC TROUGH AND
WESTERN/CENTRAL RIDGE. THE ECMWF AND CANADIAN ARE STILL THE FURTHEST
WEST AND MORE CUTOFF WITH THE GFS STILL PUSHING THE TROUGH FURTHER
TO THE EAST WHILE RETAINING THE CUTOFF. ALTHOUGH THE GFS IS SLOWER
TODAY THAN YESTERDAY. CONSIDERING THE FLOW PATTERN...CONSISTENT
ECMWF/CANADIAN AND THE SLOWER GFS...THE MORE AMPLIFIED AND SLOWER
SOLUTION LOOKS THE BEST. THE WPC MANUAL PROGS ECHO THIS AS WELL.
SAYING THAT IT LOOKS LIKE DRY AND WARMER WEATHER WILL BE THE
PREVAILING CONDITIONS FOR THIS PERIOD AND LEFT WHAT THE CRH_INIT
GAVE ME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 521 PM MDT WED SEP 23 2015
MVFR TO VFR CONDITIONS WILL PERSIST THROUGH THE FORECAST PERIOD.
KGLD COULD SEE PATCHY FOG AROUND 12Z AND KMCK WILL SEE A REDUCTION
IN CEILINGS WITH SOME LOW STRATUS IN THE 12Z TO 16Z TIME FRAME.
IMPROVED CEILINGS WILL PERSIST THROUGH THE REMAINDER OF THE DAY AT
KMCK HOWEVER PARTLY CLOUDY SKIES WILL CONTINUE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...TL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
305 PM MDT TUE SEP 22 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 211 PM MDT TUE SEP 22 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
SERIES OF H7/H5 UPPER TROUGHS PROPAGATING THROUGH A MEAN SW FLOW
ACROSS THE CENTRAL ROCKIES. THE NEAREST UPPER LOW IS NOW MOVING INTO
THE SOUTHERN PART OF OUR CWA WITH PLUME OF RICH MID LEVEL MOISTURE
SPREADING NORTH OUT OF SW KANSAS. PWATS AS INDICATED BY RAP ANALYSIS
ARE NEARING 1.4-1.5 SOUTH OF OUR CWA. STEEP LOW AND MID LEVEL LAPSE
RATES HAVE LED TO ISOLATED SHOWER/THUNDERSTORM DEVELOPMENT IN
PROXIMITY TO STALLED FRONTAL ZONE ALONG I-70 IN COLORADO. THIS
STALLED COLD FRONT EXTENDS NORTH INTO SW AND CENTRAL NEBRASKA WHERE
HIGHER CINH HAS LIMITED CONVECTIVE INITIATION.
THIS AFTERNOON-TONIGHT...ISOLATED TO SCATTERED THUNDERSTORM ACTIVITY
WILL CONTINUE TO BE POSSIBLE AHEAD OF MAIN AREA OF LARGE SCALE
FORCING (SOUTH OF TROUGH AXIS. AS THIS UPPER TROUGH SHIFTS NORTH
SHOWERS AND THUNDERSTORM SHOULD SPREAD NORTH ALONG/EAST OF CO/KS
STATE LINE. A SECOND UPPER LOW/STRONG LOBE OF VORTICITY WILL ROTATE
THROUGH THE REGION TONIGHT AND GUIDANCE IS SHOWING A PARTICULARLY
STRONG PRECIP SIGNAL WITH THIS SECONDARY UPPER LOW AROUND 06-09Z.
BEST INSTABILITY QUICKLY DROPS OFF AFTER 00Z...HOWEVER STEEP MID
LEVEL LAPSE RATES AND WEAK CAPE WILL AT LEAST SUPPORT A THREAT FOR
EMBEDDED CONVECTION OVERNIGHT. ANOMALOUSLY HIGH PWATS...DEEP
MOISTURE ADVECTION...AND CONTINUOUS SOUTH TO NORTH BUILDING/TRAINING
OF SHOWERS/THUNDERSTORMS WILL SUPPORT POSSIBLE HEAVY RAIN WITH MANY
LOCATIONS RECEIVING ONE HALF TO ONE INCH...POSSIBLY HIGHER.
WEDNESDAY...UPPER LOW SHIFTS NORTHEAST AND SLOWS DOWN OVER
CENTRAL NEBRASKA...ALLOWING FOR MOIST/WEAKLY UNSTABLE AIR MASS TO
LINGER EAST OF STALLED FRONTAL ZONE. COLD POOL ALOFT WILL SUPPORT
POSSIBLE SHOWER/THUNDERSTORM REDEVELOPMENT IN THE AFTERNOON...SO
WHILE BEST LARGE SCALE FORCING IS NORTHEAST BY MIDDAY WE WILL
CONTINUE TO SEE CHANCES THROUGH THE DAY...PARTICULARLY IN THE
EAST. GUIDANCE IS SHOWING THE POTENTIAL FOR DRIER AIR TO ADVECT IN
FROM THE WEST...SO LOCATIONS IN EASTERN COLORADO AND FAR WESTERN
KANSAS MAY REMAIN DRY WEDNESDAY AFTERNOON. I SHOWED A DECREASING
TREND IN COVERAGE FROM THE WEST TO THE EAST. HIGH TEMPS ARE TRICKY
AS CLEARING/WAA IN THE WEST COULD SUPPORT MID TO UPPER 80S FOR
HIGHS...WHILE PERSISTENT CLOUD COVER/SHOWERS EAST OF FRONTAL
ZONE/SURFACE TROUGH WOULD HOLD HIGHS DOWN IN THE 70S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 300 PM MDT TUE SEP 22 2015
MAIN FORECAST PROBLEM WILL BE CHANCES OF PRECIPITATION THROUGH
FRIDAY. SATELLITE IS SHOWING AN AMPLIFIED PATTERN OVER THE PACIFIC
WHICH THEN TRANSLATES TO A DEVELOPING TROUGH OVER THE WESTERN
PORTION OF THE COUNTRY THEN RIDGE OVER THE CENTRAL PORTION WITH
ANOTHER TROUGH OVER THE EASTERN PORTION.
AT JET LEVEL...THE GFS/CANADIAN/ECMWF WERE STARTING OUT A LITTLE
BETTER THAN THE NAM. AT MID LEVELS...THE GFS/CANADIAN WERE DOING A
LITTLE BETTER THAN THE UKMET/ECMWF. THE SREF WAS DOING THE BEST ON
THE SURFACE PATTERN. THE NAM/CANADIAN WAS DOING A LITTLE BETTER THAN
THE GFS/SREF ON THE LOW LEVEL THERMAL FIELD.
WEDNESDAY NIGHT...JET IS EAST AND SOUTH OF THE AREA. SLOW MOVING
UPPER TROUGH WITH THE CLOSED OFF PORTION OVER CENTRAL NEBRASKA. THE
TROUGH MOVES THROUGH VERY SLOWLY WITH THE TROUGH LINE NEAR THE
EASTERN END OF THE FORECAST AREA. A COUPLE DIFFERENT SHORTWAVES
ROTATE THROUGH...MAINLY ACROSS THE EAST...THROUGH THE NIGHT. SO
KEPT THE HIGHEST POPS IN THE EASTERN END.
THURSDAY/THURSDAY NIGHT...BEHAVIOR OF THE UPPER LOW BECOMES
PROBLEMATIC DURING THIS TIME. EASTWARD PROGRESSION STOPS DURING THE
DAY WITH IT SLOWLY SINKING SOUTH. AGAIN DIFFERENT SHORTWAVE TROUGHS
ROTATE AROUND THE SYSTEM AND THROUGH THE AREA...MAINLY IN THE
EAST...WITH THE UPPER SYSTEM CENTERED OVER SOUTHEAST NEBRASKA. VERY
HARD TO TIME THESE OUT WITH DIFFERENT MODELS SHOWING DIFFERENT
SCENARIOS.
COLDER AIR ALOFT WITH THETA-E LAPSE RATES VERY LOW AND
THE TQ INDEX SUPPORTIVE OF INSTABILITY SHOWERS. SO IT SHOULD NOT
TAKE TOO MUCH TO GET SHOWERS GOING. SO AT THIS TIME KEPT SLIGHT
CHANCE TO CHANCE POPS IN THE EASTERN PORTION. FRONT MOVES THROUGH IN
THE MORNING. AM THINKING MAY NOT HAVE A LOT OF SUNSHINE DUE TO THE
COLD POOL ALOFT. 850 MB TEMPERATURES SUPPORTIVE OF COOLER
TEMPERATURES AND THAT ALONG WITH THE CLOUD COVER LOWERED THE
TEMPERATURES. HOWEVER SOME GUIDANCE IS COOLER THAN WHAT I HAVE IN
THERE.
UPPER LOW THEN STARTS BACKING UP TOWARD THE WEST THROUGH THE NIGHT.
THIS PUTS THE AREA IN THE NORTHWEST QUADRANT WITH THE POTENTIAL FOR
WRAP AROUND TO OCCUR. FRONTOGENESIS AND NEGATIVE THETA-E LAPSE RATES
SHOULD MAKE IT EASY FOR WHATEVER LIFT THERE IS TO START THE
PRECIPITATION. MODELS DO SHOW LIGHT QPF CONTINUING.
FRIDAY...UPPER LOW CONTINUES TO MOVE TOWARD THE WEST AND A LITTLE TO
THE SOUTH THROUGH THE DAY. RATHER STRONG SHORTWAVE/FRONTOGENESIS
ROTATING AROUND THE NORTH AND WEST SIDES OF THE SYSTEM. AGAIN
COLD POOL REMAINS ON TOP OF US WITH THE NEGATIVE THETA-E LAPSE
RATES IN PLACE AND THE TQ INDEX SUPPORT OF INSTABILITY SHOWERS.
PROBLEM IS THE MODELS ARE NOT SHOWING A LOT OF MOISTURE. HOWEVER
AM NOT SURE THAT THE MODELS ARE TOTALLY CATCHING HIS UNUSUAL
SCENARIO. SO KEPT A SLIGHT CHANCE THROUGH THE DAY. WITH THE UPPER
LOW SINKING ON TOP OF US...MORE COLD AIR MOVING INTO THE AREA AND
THE CLOUD COVER...COOLED THE TEMPERATURES A LITTLE BIT FROM WHERE
THEY WERE.
FRIDAY NIGHT THROUGH TUESDAY...AFTER ABOUT A DAY INTO THIS PERIOD
THE MODELS...DETERMINISTIC/ENSEMBLES...START DIVERGING SIGNIFICANTLY.
IN FACT BY THE END OF THE PERIOD THE ECMWF AND GFS ARE COMPLETELY
OUT OF PHASE. SO CONFIDENCE IN THE OUTCOME OF THIS IS LOW.
CONSIDERING THE CURRENT FLOW PATTERN WOULD BELIEVE THAT THE
AMPLIFIED PATTERN SHOULD CONTINUE. SAYING THAT THE GFS IS THE BIG
OUTLIER. THE ECMWF AND TO A LESSER DEGREE THE CANADIAN ARE MORE
AMPLIFIED WITH THE CANADIAN ACTUALLY IN THE MIDDLE OF THE SOLUTION
FIELD.
SAYING ALL THAT...THE WPC MANUAL PROGS TAKE THAT INTO ACCOUNT AND
SIDE IN THAT DIRECTION. SO HAVE LITTLE CONFIDENCE IN MAKING ANY
SIGNIFICANT CHANGES TO WHAT THE INIT...WHICH IS DRY THROUGH THE
PERIOD...GAVE. SO MADE NO CHANGES OVERALL TO WHAT I WAS GIVEN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1143 AM MDT TUE SEP 22 2015
WIDESPREAD SHOWERS WITH ISOLATED/EMBEDDED WEAK THUNDERSTORMS
WILL OVERSPREAD BOTH KGLD AND KMCK TERMINALS FROM THE SOUTH TO
THE NORTH FROM LATE THIS AFTERNOON THROUGH THE OVERNIGHT PERIOD.
BEST COVERAGE WILL BE IN THE 05-10Z TIME PERIOD AT BOTH
TERMINALS...WITH COVERAGE DECREASING AT KGLD AFTER 12Z. MVFR
CONDITIONS WILL BE POSSIBLE WITH MODERATE SHOWERS...HOWEVER AT
THIS TIME GUIDANCE IS ONLY SHOWING PREVAILING 2500 KFT CIGS AT
KMCK AFTER 09Z...WITH ONLY TEMPO CONDITIONS POSSIBLE AT KGLD.
CONFIDENCE WAS TOO LOW TO LOWER CONDITIONS BELOW VFR AT THIS
TIME...BUT THIS WILL NEED TO BE MONITORED. GUSTY SOUTH WINDS WILL
CONTINUE AT BOTH TERMINALS...EVENTUALLY SHIFTING TO THE SOUTHWEST
BY THE END OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
211 PM MDT TUE SEP 22 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 211 PM MDT TUE SEP 22 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS A
SERIES OF H7/H5 UPPER TROUGHS PROPAGATING THROUGH A MEAN SW FLOW
ACROSS THE CENTRAL ROCKIES. THE NEAREST UPPER LOW IS NOW MOVING INTO
THE SOUTHERN PART OF OUR CWA WITH PLUME OF RICH MID LEVEL MOISTURE
SPREADING NORTH OUT OF SW KANSAS. PWATS AS INDICATED BY RAP ANALYSIS
ARE NEARING 1.4-1.5 SOUTH OF OUR CWA. STEEP LOW AND MID LEVEL LAPSE
RATES HAVE LED TO ISOLATED SHOWER/THUNDERSTORM DEVELOPMENT IN
PROXIMITY TO STALLED FRONTAL ZONE ALONG I-70 IN COLORADO. THIS
STALLED COLD FRONT EXTENDS NORTH INTO SW AND CENTRAL NEBRASKA WHERE
HIGHER CINH HAS LIMITED CONVECTIVE INITIATION.
THIS AFTERNOON-TONIGHT...ISOLATED TO SCATTERED THUNDERSTORM ACTIVITY
WILL CONTINUE TO BE POSSIBLE AHEAD OF MAIN AREA OF LARGE SCALE
FORCING (SOUTH OF TROUGH AXIS. AS THIS UPPER TROUGH SHIFTS NORTH
SHOWERS AND THUNDERSTORM SHOULD SPREAD NORTH ALONG/EAST OF CO/KS
STATE LINE. A SECOND UPPER LOW/STRONG LOBE OF VORTICITY WILL ROTATE
THROUGH THE REGION TONIGHT AND GUIDANCE IS SHOWING A PARTICULARLY
STRONG PRECIP SIGNAL WITH THIS SECONDARY UPPER LOW AROUND 06-09Z.
BEST INSTABILITY QUICKLY DROPS OFF AFTER 00Z...HOWEVER STEEP MID
LEVEL LAPSE RATES AND WEAK CAPE WILL AT LEAST SUPPORT A THREAT FOR
EMBEDDED CONVECTION OVERNIGHT. ANOMALOUSLY HIGH PWATS...DEEP
MOISTURE ADVECTION...AND CONTINUOUS SOUTH TO NORTH BUILDING/TRAINING
OF SHOWERS/THUNDERSTORMS WILL SUPPORT POSSIBLE HEAVY RAIN WITH MANY
LOCATIONS RECEIVING ONE HALF TO ONE INCH...POSSIBLY HIGHER.
WEDNESDAY...UPPER LOW SHIFT NORTHEAST AND SLOWS DOWN OVER CENTRAL
NEBRASKA...ALLOWING FOR MOIST/WEAKLY UNSTABLE AIR MASS TO LINGER
EAST OF STALLED FRONTAL ZONE. COLD POOL ALOFT WILL SUPPORT POSSIBLE
SHOWER/THUNDERSTORM REDEVELOPMENT IN THE AFTERNOON...SO WHILE BEST
LARGE SCALE FORCING IS NORTHEAST BY MIDDAY WE WILL CONTINUE TO SEE
CHANCES THROUGH THE DAY...PARTICULARLY IN THE EAST. GUIDANCE IS
SHOWING THE POTENTIAL FOR DRIER AIR TO ADVECT IN FROM THE
WEST...SO LOCATIONS IN EASTERN COLORADO AND FAR WESTERN KANSAS MAY
REMAIN DRY WEDNESDAY AFTERNOON. I SHOWED A DECREASING TREND IN
COVERAGE FROM THE WEST TO THE EAST. HIGH TEMPS ARE TRICKY AS
CLEARING/WAA IN THE WEST COULD SUPPORT MID TO UPPER 80S FOR
HIGHS...WHILE PERSISTENT CLOUD COVER/SHOWERS EAST OF FRONTAL
ZONE/SURFACE TROUGH WOULD HOLD HIGHS DOWN IN THE 70S.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 215 AM MDT TUE SEP 22 2015
THE LONG TERM FORECAST PERIOD BEGINS WITH A BUILDING UPPER LEVEL
RIDGE OVER THE CENTRAL PORTIONS OF THE CONUS FRIDAY AND HEADING INTO
NEXT WEEKEND. AT THE SURFACE...A LINGERING CONVERGENCE BOUNDARY
FRIDAY WILL BRING CHANCES FOR SHOWERS AND A FEW SCATTERED
THUNDERSTORMS TO THE FORECAST AREA...MAINLY EAST OF HIGHWAY 83. THE
LINGERING COLD AIR FROM THE FRONT WILL KEEP TEMPERATURES COOLER IN
THE UPPER 70S.
ONCE THE COLD FRONTAL BOUNDARY PUSHES EASTWARD WITH SUBSIDENCE ALOFT
PROVIDED BY THE UPPER LEVEL RIDGE...DRY AND WARMER CONDITIONS CAN BE
EXPECTED FOR THE WEEKEND AND THE EARLY PART OF NEXT WEEK. HIGH
TEMPERATURES WILL BE IN THE MID TO UPPER 80S WITH LOW TEMPERATURES
IN THE MID TO UPPER 50S. NO SIGNIFICANT WEATHER IS EXPECTED AT THIS
TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1143 AM MDT TUE SEP 22 2015
WIDESPREAD SHOWERS WITH ISOLATED/EMBEDDED WEAK THUNDERSTORMS
WILL OVERSPREAD BOTH KGLD AND KMCK TERMINALS FROM THE SOUTH TO
THE NORTH FROM LATE THIS AFTERNOON THROUGH THE OVERNIGHT PERIOD.
BEST COVERAGE WILL BE IN THE 05-10Z TIME PERIOD AT BOTH
TERMINALS...WITH COVERAGE DECREASING AT KGLD AFTER 12Z. MVFR
CONDITIONS WILL BE POSSIBLE WITH MODERATE SHOWERS...HOWEVER AT
THIS TIME GUIDANCE IS ONLY SHOWING PREVAILING 2500 KFT CIGS AT
KMCK AFTER 09Z...WITH ONLY TEMPO CONDITIONS POSSIBLE AT KGLD.
CONFIDENCE WAS TOO LOW TO LOWER CONDITIONS BELOW VFR AT THIS
TIME...BUT THIS WILL NEED TO BE MONITORED. GUSTY SOUTH WINDS WILL
CONTINUE AT BOTH TERMINALS...EVENTUALLY SHIFTING TO THE SOUTHWEST
BY THE END OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...DR
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 PM EDT TUE SEP 22 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 340 PM EDT TUE SEP 22 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER THE OHIO VALLEY
AND NORTHEAST. THERE IS A WEAK LEE SIDE LOW NEAR THE SPINE OF THE
APPALACHIANS AND THIS HAS BEEN ENOUGH IN THE PAST COUPLE OF DAYS
TO GENERATE SOME LIGHT SHOWERS ON THE OTHER SIDE OF OUR BORDER.
NOTHING HAS POPPED UP ON RADAR SO FAR...THOUGH...AND THE CU FIELD
IS RATHER SPARSE. AMPLE SUNSHINE BETWEEN THE CU ALLOWED
TEMPERATURES TO PEAK IN THE MID TO UPPER 70S THROUGH THE AREA
THIS AFTERNOON WITH A FEW 80 DEGREE REPORTS NOTED. DEWPOINTS...
MEANWHILE...ARE IN THE MID TO UPPER 50S WITH A FEW LOW 60S SEEN IN
THE EAST. WINDS HAVE GENERALLY BEEN OUT OF THE NORTHEAST AT 5 TO
10 KTS THIS AFTERNOON.
THE MODELS ARE IN GOOD AGREEMENT ALOFT AS THEY ALL DEPICT A BENIGN
PATTERN CONSISTING OF FAST FLOW NORTH OF THE U.S. CANADIAN BORDER
AND GENERALLY HIGH HEIGHTS THROUGH THE OHIO VALLEY. THERE WILL BE
A SMATTERING OF ENERGY EAST OF KENTUCKY ASSOCIATED WITH A
WEAKENING UPPER LEVEL LOW OVER THE SOUTHEAST PARTS OF THE NATION.
EVEN A SHORTWAVE TROUGH COMING OUT OF THE NORTHERN PLAINS LATER
WEDNESDAY WILL WEAKEN AND SLOW WITH ITS APPROACH TOWARD THE
MISSISSIPPI RIVER. AS SUCH...PERSISTENCE WILL CONTINUE TO WIN THE
DAY. GIVEN THE MODEL AGREEMENT AND LACK OF ANY SIGNIFICANT
FEATURES WILL FAVOR THE HIGHER RESOLUTION HRRR AND NAM12 MODELS
FOR WX SPECIFICS IN A REGIME OF PERSISTENCE.
SENSIBLE WEATHER WILL FEATURE MORE OF THE SAME IN THIS STAGNANT
PATTERN. TEMPERATURES OVERNIGHT WILL FALL TO VALUES JUST ABOVE
LAST NIGHT/S LOWS. EXPECT FOG TO DEVELOP THROUGH THE NIGHT WITH
LOCALLY DENSE PATCHES TOWARD DAWN...ESPECIALLY NEAR RIVERS AND
LAKES. THIS FOG WILL BURN OFF BY 14Z WITH ANOTHER PARTLY TO MOSTLY
SUNNY DAY AS TEMPERATURES CLIMB A COUPLE OF DEGREES HIGHER THAN
TODAY. A SIMILAR PATTERN CAN BE ANTICIPATED ON WEDNESDAY NIGHT
WITH READINGS AGAIN A NOTCH MILDER BUT WITH SIMILAR AMOUNTS OF
LATE NIGHT FOG.
FOR TEMPERATURES AND DEWPOINTS...USED THE SHORTBLEND MODEL
GUIDANCE AS A STARTING POINT THROUGH THE BULK OF THE NIGHT
BEFORE FAVORING THE SUPERBLEND FOR THE REST OF THE SHORT TERM
PORTION OF THE FORECAST. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO
THE NIGHT TIME TEMPERATURES TO BETTER CAPTURE THE EFFECTS OF AN
INVERSION ON OUR TERRAIN. AS FOR POPS...KEPT THEM IN THE SINGLE
DIGITS THROUGH THURSDAY MORNING...SIMILAR TO MOS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE SEP 22 2015
THE EXTENDED PORTION OF THE FORECAST BEGINS ON THURSDAY WITH A
PERSISTENT BROAD UPPER LEVEL RIDGE IN PLACE OVER THE ENTIRE CONUS.
TO BEGIN THE EXTENDED...THE UPPER LEVEL FLOW REMAINS TO THE NORTH
ALONG THE CANADIAN BORDER AS WELL. THE AREA IN QUESTION WILL
CONTINUE TO BE THE SOUTHEASTERN CONUS WITH A COUPLE TROPICAL LOWS
MEANDERING NORTHERLY OUT OF THE GULF OF MEXICO AND SOUTHEAST
ATLANTIC COAST BY THE WEEKEND AND INTO THE START OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 225 PM EDT TUE SEP 22 2015
PERSISTENCE WILL CONTINUE TO DOMINATE THE WEATHER PATTERN.
ACCORDINGLY...EXPECT MOSTLY CLEAR SKIES THROUGH THE NIGHT AND INTO
WEDNESDAY. AGAIN...PATCHY FOG...LOCALLY DENSE...CAN BE EXPECTED
TOWARD DAWN. THIS WILL AFFECT SOME OF THE TAF SITES AT AN EXTENT
SIMILAR TO THIS MORNING. HAVE SET THEM ALL UP ACCORDINGLY. WINDS
WILL AVERAGE AROUND 5 KTS OR LESS...GENERALLY OUT OF THE
NORTHEAST...THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
225 PM EDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 210 PM EDT TUE SEP 22 2015
THE CURRENT FORECAST IS ON TRACK SO HAVE JUST UPDATED THE T AND TD
GRIDS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE
NDFD AND WEB SERVERS.
UPDATE ISSUED AT 1005 AM EDT TUE SEP 22 2015
13Z SFC ANALYSIS SHOWS A PERSISTENT PATTERN ACROSS THE AREA WITH
HIGH PRESSURE GENERALLY IN CONTROL. THERE IS A LEE SIDE LOW
EVIDENT ON THE OTHER SIDE OF THE APPALACHIANS THAT MAY PROMPT SOME
WEAK CONVECTION IN THOSE PARTS AGAIN THIS AFTERNOON. THIS
DEVELOPMENT IS ALSO SUPPORTED BY THE LOWER HEIGHTS OF A LOCALIZED
UPPER LEVEL LOW JUST EAST OF KENTUCKY. EVEN THE HRRR SUGGESTS A
POTENTIAL FOR SPOTTY ACTIVITY THIS AFTERNOON AS A RESULT OF THIS.
WILL KEEP EAST KENTUCKY DRY...THOUGH...GIVEN THE PERSISTENT
PATTERN WHILE HAVING THE HIGHEST...STILL JUST SINGLE DIGIT...POPS
OVER THE FAR EAST NEAR THE SPINE OF THE APPALACHIANS. THE EARLY
MORNING FOG AND DENSE FOG IS JUST ABOUT GONE SO WILL UPDATE TO
REMOVE THAT FROM THE HWO AND ZONES. TEMPERATURES AND DEWPOINTS ARE
MOSTLY ON TRACK...RUNNING IN THE MID 50S TO LOWER 60S AND UPPER
50S RESPECTIVELY. DID INFUSE THE LATEST SHORTBLEND GUIDANCE INTO
THEM AND ALSO ADJUST FOR THE LATEST OBS AND TRENDS. MEANWHILE
WINDS ARE LIGHT. JUST A SMATTERING OF LOW AND MID LEVEL CLOUDS ARE
FOUND IN THE EAST...SOME ASSOCIATED WITH THE LIFTING FOG. EXPECT
THESE TO WANE INITIALLY BEFORE SOME BUILDUP IN THE AFTERNOON...
SIMILAR TO YESTERDAY. HAVE UPDATED THE ZONES AND HWO WITH THE
LATEST GRIDS SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 813 AM EDT TUE SEP 22 2015
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO ALIGN WITH
THE CURRENT TRENDS IN OBSERVATIONS..OTHERWISE THE FORECAST IS ON
TRACK.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 344 AM EDT TUE SEP 22 2015
THE LATEST SURFACE MAP FEATURES A BROAD AREA OF HIGH PRESSURE
ACROSS THE OHIO VALLEY...WITH THE CENTER SITUATED ACROSS NORTHERN
NEW ENGLAND. ALOFT...A TROUGH AXIS IS ALIGNED JUST WEST OF THE
APPALACHIANS...WITH RIDGING FOUND FROM THE SOUTHERN PLAINS TO THE
GREAT LAKES.
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH THE
TROUGH AXIS GRADUALLY SHIFTING EAST AND DAMPENING WITH TIME.
THIS WILL ALLOW RIDGING TO TAKE A BETTER HOLD ACROSS THE OHIO
AND TENNESSEE VALLEYS.
BESIDES SOME CLOUDS IN THE EAST...ANOTHER MOSTLY SUNNY DAY IS
EXPECTED ACROSS EASTERN KENTUCKY WITH HIGHS REACHING A FEW DEGREES
WARMER THAN YESTERDAY...GENERALLY MID TO UPPER 70S. TONIGHT WILL
NOT BE AS COOL AS THIS MORNING...WITH LOWS GETTING DOWN INTO THE
LOWER 50S IN SOME OF THE COOLER SPOTS. WEDNESDAY WILL FEATURE
HIGHS A BIT MILDER STILL...WITH UPPER 70S TO AROUND 80 DEGREES
EXPECTED UNDER MOSTLY SUNNY SKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE SEP 22 2015
HIGH PRESSURE RIDGING WILL BE IN FULL FORCE ACROSS THE OHIO RIVER
VALLEY TO START OFF THE EXTENDED...AS AN UPPER LEVEL LOW GAINS
STRENGTH TO OUR SOUTH ACROSS THE GULF OF MEXICO AND BORDERING
STATES. THIS LOW IS EXPECTED TO REMAIN FAIRLY STATIONARY THROUGH
FRIDAY...ALLOWING DRY WEATHER TO PREVAIL...BUT SHOULD FINALLY START
TRACKING NORTHWARD AS WE HEAD INTO THE WEEKEND...REACHING KY BY
SATURDAY AFTERNOON/EVENING. ACCORDING TO THE LATEST ECMWF...SEVERAL
SMALLER WAVES OF ENERGY WILL LIKELY ROTATE AROUND THIS
LOW...BRINGING SOME CHANCES OF RAIN TO OUR SOUTHERN AND EASTERN
BORDERS BY FRIDAY AND INTO THE DAY SATURDAY. THE GFS ON THE OTHER
HAND SPLITS THE LOW INTO TWO SECTIONS...ONE WHICH WILL DRIFT WELL
TO OUR WEST AND ANOTHER WHICH WILL DRIFT JUST EAST OF THE STATE.
IF THIS IS THE CASE...WE MAY ONLY SEE PRECIP IN THE FAR EAST
DURING PEAK HEATING ON SATURDAY. GIVEN THE LOW CONFIDENCE...STUCK
WITH A MODEL CONSENSUS AND NEIGHBORING OFFICE COLLABORATION ON THE
TIMING AND LOCATION OF THE ABOVE MENTIONED PRECIP BOTH DURING THE
WEEKEND AND FOR THE REMAINDER OF THE EXTENDED.
REGARDLESS...WE ARE NOT EXPECTING ANY BOUNDARIES TO MOVE THROUGH THE
REGION...SO ANY CONVECTION WILL BE LIMITED TO DAYTIME
HEATING/INSTABILITY AND WILL BE WEAK AT BEST. AS SUCH...CONTINUED
WITH ONLY THE MENTION OF RAIN SHOWERS AND DID NOT INCLUDE ANY
THUNDER. WINDS THROUGH THE WEEKEND WILL GENERALLY BE FROM THE EAST
AS CLOUDS SLOWLY INCREASE IN RESPONSE TO THE NEARING UPPER LEVEL LOW
AND INCREASING MOISTURE/RAIN CHANCES. HOWEVER...GIVEN THAT NO MAJOR
CAA OR WAA ASSOCIATED WITH ANY SURFACE BOUNDARIES WILL
OCCUR...TEMPERATURES SHOULD REMAIN FAIRLY STEADY STATE AND VERY NEAR
SEASONABLE NORMS. THE EXCEPTION WILL BE THURSDAY...STARTING OFF THE
PERIOD...AS HIGH PRESSURE STILL IN PLACE WILL RESULT IN MOSTLY SUNNY
SKIES ACROSS THE REGION AND ALLOW TEMPERATURES TO CLIMB INTO THE LOW
80S IN MOST LOCATIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 225 PM EDT TUE SEP 22 2015
PERSISTENCE WILL CONTINUE TO DOMINATE THE WEATHER PATTERN.
ACCORDINGLY...EXPECT MOSTLY CLEAR SKIES THROUGH THE NIGHT AND INTO
WEDNESDAY. AGAIN...PATCHY FOG...LOCALLY DENSE...CAN BE EXPECTED
TOWARD DAWN. THIS WILL AFFECT SOME OF THE TAF SITES AT AN EXTENT
SIMILAR TO THIS MORNING. HAVE SET THEM ALL UP ACCORDINGLY. WINDS
WILL AVERAGE AROUND 5 KTS OR LESS...GENERALLY OUT OF THE
NORTHEAST...THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1005 AM EDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 1005 AM EDT TUE SEP 22 2015
13Z SFC ANALYSIS SHOWS A PERSISTENT PATTERN ACROSS THE AREA WITH
HIGH PRESSURE GENERALLY IN CONTROL. THERE IS A LEE SIDE LOW
EVIDENT ON THE OTHER SIDE OF THE APPALACHIANS THAT MAY PROMPT SOME
WEAK CONVECTION IN THOSE PARTS AGAIN THIS AFTERNOON. THIS
DEVELOPMENT IS ALSO SUPPORTED BY THE LOWER HEIGHTS OF A LOCALIZED
UPPER LEVEL LOW JUST EAST OF KENTUCKY. EVEN THE HRRR SUGGESTS A
POTENTIAL FOR SPOTTY ACTIVITY THIS AFTERNOON AS A RESULT OF THIS.
WILL KEEP EAST KENTUCKY DRY...THOUGH...GIVEN THE PERSISTENT
PATTERN WHILE HAVING THE HIGHEST...STILL JUST SINGLE DIGIT...POPS
OVER THE FAR EAST NEAR THE SPINE OF THE APPALACHIANS. THE EARLY
MORNING FOG AND DENSE FOG IS JUST ABOUT GONE SO WILL UPDATE TO
REMOVE THAT FROM THE HWO AND ZONES. TEMPERATURES AND DEWPOINTS ARE
MOSTLY ON TRACK...RUNNING IN THE MID 50S TO LOWER 60S AND UPPER
50S RESPECTIVELY. DID INFUSE THE LATEST SHORTBLEND GUIDANCE INTO
THEM AND ALSO ADJUST FOR THE LATEST OBS AND TRENDS. MEANWHILE
WINDS ARE LIGHT. JUST A SMATTERING OF LOW AND MID LEVEL CLOUDS ARE
FOUND IN THE EAST...SOME ASSOCIATED WITH THE LIFTING FOG. EXPECT
THESE TO WANE INITIALLY BEFORE SOME BUILDUP IN THE AFTERNOON...
SIMILAR TO YESTERDAY. HAVE UPDATED THE ZONES AND HWO WITH THE
LATEST GRIDS SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 813 AM EDT TUE SEP 22 2015
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO ALIGN WITH
THE CURRENT TRENDS IN OBSERVATIONS..OTHERWISE THE FORECAST IS ON
TRACK.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 344 AM EDT TUE SEP 22 2015
THE LATEST SURFACE MAP FEATURES A BROAD AREA OF HIGH PRESSURE
ACROSS THE OHIO VALLEY...WITH THE CENTER SITUATED ACROSS NORTHERN
NEW ENGLAND. ALOFT...A TROUGH AXIS IS ALIGNED JUST WEST OF THE
APPALACHIANS...WITH RIDGING FOUND FROM THE SOUTHERN PLAINS TO THE
GREAT LAKES.
THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH THE
TROUGH AXIS GRADUALLY SHIFTING EAST AND DAMPENING WITH TIME.
THIS WILL ALLOW RIDGING TO TAKE A BETTER HOLD ACROSS THE OHIO
AND TENNESSEE VALLEYS.
BESIDES SOME CLOUDS IN THE EAST...ANOTHER MOSTLY SUNNY DAY IS
EXPECTED ACROSS EASTERN KENTUCKY WITH HIGHS REACHING A FEW DEGREES
WARMER THAN YESTERDAY...GENERALLY MID TO UPPER 70S. TONIGHT WILL
NOT BE AS COOL AS THIS MORNING...WITH LOWS GETTING DOWN INTO THE
LOWER 50S IN SOME OF THE COOLER SPOTS. WEDNESDAY WILL FEATURE
HIGHS A BIT MILDER STILL...WITH UPPER 70S TO AROUND 80 DEGREES
EXPECTED UNDER MOSTLY SUNNY SKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 344 AM EDT TUE SEP 22 2015
HIGH PRESSURE RIDGING WILL BE IN FULL FORCE ACROSS THE OHIO RIVER
VALLEY TO START OFF THE EXTENDED...AS AN UPPER LEVEL LOW GAINS
STRENGTH TO OUR SOUTH ACROSS THE GULF OF MEXICO AND BORDERING
STATES. THIS LOW IS EXPECTED TO REMAIN FAIRLY STATIONARY THROUGH
FRIDAY...ALLOWING DRY WEATHER TO PREVAIL...BUT SHOULD FINALLY START
TRACKING NORTHWARD AS WE HEAD INTO THE WEEKEND...REACHING KY BY
SATURDAY AFTERNOON/EVENING. ACCORDING TO THE LATEST ECMWF...SEVERAL
SMALLER WAVES OF ENERGY WILL LIKELY ROTATE AROUND THIS
LOW...BRINGING SOME CHANCES OF RAIN TO OUR SOUTHERN AND EASTERN
BORDERS BY FRIDAY AND INTO THE DAY SATURDAY. THE GFS ON THE OTHER
HAND SPLITS THE LOW INTO TWO SECTIONS...ONE WHICH WILL DRIFT WELL
TO OUR WEST AND ANOTHER WHICH WILL DRIFT JUST EAST OF THE STATE.
IF THIS IS THE CASE...WE MAY ONLY SEE PRECIP IN THE FAR EAST
DURING PEAK HEATING ON SATURDAY. GIVEN THE LOW CONFIDENCE...STUCK
WITH A MODEL CONSENSUS AND NEIGHBORING OFFICE COLLABORATION ON THE
TIMING AND LOCATION OF THE ABOVE MENTIONED PRECIP BOTH DURING THE
WEEKEND AND FOR THE REMAINDER OF THE EXTENDED.
REGARDLESS...WE ARE NOT EXPECTING ANY BOUNDARIES TO MOVE THROUGH THE
REGION...SO ANY CONVECTION WILL BE LIMITED TO DAYTIME
HEATING/INSTABILITY AND WILL BE WEAK AT BEST. AS SUCH...CONTINUED
WITH ONLY THE MENTION OF RAIN SHOWERS AND DID NOT INCLUDE ANY
THUNDER. WINDS THROUGH THE WEEKEND WILL GENERALLY BE FROM THE EAST
AS CLOUDS SLOWLY INCREASE IN RESPONSE TO THE NEARING UPPER LEVEL LOW
AND INCREASING MOISTURE/RAIN CHANCES. HOWEVER...GIVEN THAT NO MAJOR
CAA OR WAA ASSOCIATED WITH ANY SURFACE BOUNDARIES WILL
OCCUR...TEMPERATURES SHOULD REMAIN FAIRLY STEADY STATE AND VERY NEAR
SEASONABLE NORMS. THE EXCEPTION WILL BE THURSDAY...STARTING OFF THE
PERIOD...AS HIGH PRESSURE STILL IN PLACE WILL RESULT IN MOSTLY SUNNY
SKIES ACROSS THE REGION AND ALLOW TEMPERATURES TO CLIMB INTO THE LOW
80S IN MOST LOCATIONS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 813 AM EDT TUE SEP 22 2015
MVFR OR WORSE FOG WILL BURN OFF BETWEEN 13 AND 14Z. FEW TO
SCATTERED STRATOCU IN THE 3-5K FEET AGL RANGE WILL BE SEEN IN THE
EAST TODAY...BEFORE SKIES MAINLY CLEAR OUT TONIGHT. MVFR OR WORSE
FOG WILL LIKELY FORM ONCE AGAIN BETWEEN 06 AND 12Z...MAINLY IN THE
VALLEYS. WINDS WILL AVERAGE AROUND 5 KTS OR LESS...GENERALLY OUT
OF THE NORTHEAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...JMW
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
319 PM EDT TUE SEP 22 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 319 PM EDT TUE SEP 22 2015
DRY AND MOSTLY CLEAR WEATHER IS EXPECTED INTO EARLY NEXT WEEK. HIGH
TEMPERATURES WILL BE IN THE MID TO UPPER 70S...WHICH IS 5 TO 10
DEGREES ABOVE NORMAL FOR THE END OF SEPTEMBER.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 319 PM EDT TUE SEP 22 2015
MAIN CONCERN IS CLOUDINESS TONIGHT POSSIBLE EXTENDING SOUTH INTO OUR
NORTHERN FORECAST AREA. WE EXPECT PRECIPITATION TO REMAIN WELL NORTH
OF THE AREA BASED ON A CONSENSUS OF CONVECTION ALLOWING MODELS.
CONFIDENCE IS HIGH THAT THE REST OF THE PERIOD WILL REMAIN DRY.
AT 1 PM...A FRONT EXTENDED FROM EASTERN LAKE SUPERIOR ACROSS
WISCONSIN...NORTHERN IOWA...AND NEBRASKA. THIS BOUNDARY WILL PIVOT
CLOCKWISE AND SPREAD ASSOCIATED CLOUDINESS SOUTH INTO NORTHERN
LOWER MICHIGAN. THIS CLOUDINESS MAY PERSIST A GOOD PART OF
WEDNESDAY OVER NORTHERN LOWER WITH LESS IMPACT OVER SOUTHWEST
LOWER.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WILL BE DOMINATED BY SURFACE
HIGH PRESSURE CENTERED TO THE NORTHEAST AND LOCAL WINDS FROM THE
EAST...WHICH IS TYPICALLY A DRY PATTERN. THERE IS EXCELLENT
CONSENSUS AMONG THE MODELS WITH THIS...SO FORECAST CERTAINTY IS
GOOD.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 319 PM EDT TUE SEP 22 2015
HAVE MAINTAINED THE DRY FORECAST THROUGH THE LONG TERM PERIOD OF
FRIDAY THROUGH TUESDAY. THE ECMWF AND GFS ARE PRETTY SIMILAR INTO
SUNDAY...WHICH IS WHEN DIFFERENCES BEGIN TO SHOW UP.
DRY WEATHER WITH 500MB RIDGING LOOKS TO BE A SOLID FORECAST THROUGH
SUNDAY. ON SUNDAY...THE GFS MAINTAINS THE RIDGING...WHILE
THE ECMWF DRIVES A TROUGH INTO THE NORTHERN PLAINS. ON MONDAY...THE
ECMWF SWINGS THE TROUGH INTO THE GREAT LAKES WHERE AS THE GFS
CONTINUES THE RIDGING. BIG DIFFERENCES ARE IN PLAY BY
TUESDAY...WHERE THE OPERATIONAL ECMWF HAS A TROUGH IN THE GREAT
LAKES AND A RIDGE IN THE PLAINS. THE GFS ON TUESDAY IS THE OPPOSITE.
BASED ON THE POOR CONTINUITY DECIDED TO CONTINUE THE DRY FORECAST
EARLY NEXT WEEK AND WAIT FOR MORE OF A CONSENSUS BEFORE FLIPPING THE
FORECAST COOLER AND WETTER FOR MONDAY INTO TUESDAY.
DRY AND FAIR WEATHER WILL BE THE THEME OF THE LONG TERM...WITH HIGH
CONFIDENCE THROUGH SUNDAY. HIGHS ARE FORECAST TO BE IN THE 70S EACH
DAY. AGAIN...CONFIDENCE SLIDES A BIT EARLY NEXT WEEK GIVEN THE
MODEL VARIABILITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 156 PM EDT TUE SEP 22 2015
VFR WEATHER IS EXPECTED TO DOMINATE THE NEXT 24 HOURS ONCE AGAIN.
HIGH PRESSURE WILL BRING FAIR WEATHER AND LIGHT WINDS. THE MAIN
EXCEPTION TO THIS IS THE CHANCE FOR SOME FOG TONIGHT. ONLY HAVE
FOG IN THE TAFS AT KJXN AS ITS THE ONLY SITE THAT SAW IT LAST
NIGHT. THE FOG HAS BEEN VERY SHALLOW WITH NO HINTS OF STRATUS ON
THE FIRST DAYLIGHT SATELLITE PICS. EXPECTING THE SAME TONIGHT. FOG
WOULD BE IN THE 06Z-1030Z TIME FRAME AND BE HIGHLY VARIABLE AT
KJXN.
SOME OF THE CLOUDS TO THE WEST OF LAKE MICHIGAN MAY TREND TO
SNEAK INTO WEST CENTRAL LOWER MICHIGAN TONIGHT AND WEDNESDAY
MORNING...BUT ONLY BROUGHT 5000FT SCATTERED CLOUDS INTO KMKG.
WINDS WILL BE LESS THAN 10 KNOTS THROUGH THE PERIOD.
&&
.MARINE...
ISSUED AT 319 PM EDT TUE SEP 22 2015
LUDINGTON BUOY HAS BEEN SLIGHTLY OVER-PERFORMING AROUND 3 FEET THE
LAST SEVERAL HOURS. BIG SABLE POINT AND LUDINGTON SITES HAVE BEEN
REPORTING GUSTS OF 15 TO 20 KT FROM THE SOUTH WHICH MAY BE AIDING
THE WAVE GROWTH. ADDITIONALLY...RECENT HRRR RUNS SUGGEST A CORRIDOR
OF STRONGER SOUTHERLY WINDS HAVE BEEN OCCURRING JUST OFFSHORE.
EXPECT WINDS TO RELAX THIS EVENING AND SHIFT TO THE SOUTHEAST WITH
A LAND BREEZE...WHICH SHOULD ALLOW WAVES TO DIMINISH. AFTER
THIS...THERE ARE NO CONCERNS.
&&
.HYDROLOGY...
ISSUED AT 319 PM EDT TUE SEP 22 2015
NO PRECIPITATION IS FORECAST THROUGH THROUGH THIS WEEK. RIVER
LEVELS ARE EXPECTED TO HOLD STEADY OR FALL SLOWLY THROUGH THE
WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...TJT
MARINE...TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
120 PM EDT TUE SEP 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE SEP 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL FLOW
FROM THE PAC NW THROUGH SRN CANADA. A VIGOROUS SHORTWAVE TROUGH WAS
LIFTING THROUGH SRN HUDSON BAY WITH ITS TAIL EXTENDING THROUGH NW
ONTARIO TO NRN MN. AT THE SFC...A COLD FRONT STRETCHED FROM JUST
WEST OF JAMES BAY TO THE MN ARROWHEAD. WEAK MID LEVEL QVECTOR CONV
ASSOCIATED WITH THE SHRTWV AND A NARROW RIBBON OF
MOISTURE/INSTABILITY (PWAT TO 1.1 INCHES AND MUCAPE TO AROUND 500
J/KG) SUPPORTED A LINE OF SHRA/TSRA OVER NRN LAKE SUPERIOR. THERE
WERE ONLY ISOLD SHRA FARTHER SW INTO NW WI WHERE THE MID LEVEL
FORCING WAS WEAKER.
TODAY...MODELS SUGGEST THAT THE COLD FRONT WILL MOVE INTO CNTRL
UPPER MI BY AROUND 18Z AND WILL SAG INTO FAR SRN UPPER MI BY 00Z.
WITH ONLY WEAK INSTABILITY AND FORCING ALONG THIS FEATURE...EXPECT
MAINLY JUST ISOLD SHRA/TSRA OVER THE WEST HALF THIS MORNING AND OVER
THE SOUTH AND EAST THIS AFTERNOON. INCREASING CLOUDS ALONG AND AHEAD
OF THE FRONT WILL ALSO LIMIT ANY INCREASE IN INSTABILITY. EVEN WITH
THE GREATER CLOUD COVER...TEMPS WILL AGAIN BE SLIGHTLY ABOVE NORMAL
WITH HIGHS IN THE UPPER 60S TO AROUND 70.
TONIGHT...THERE MAY BE SOME LINGERING SHRA/TSRA OVER THE FAR S CNTRL
IN THE EVENING. OTHERWISE...CLEARING WITH DRIER AIR MOVING IN WILL
ALLOW TEMPS TO FALL INTO THE MID 40S INLAND. EXPECT PATCHY
FOG...MAINLY OVER THE EAST WHERE THE GREATER LOW LEVEL MOISTURE
LINGERS. WAA AND MOISTURE ADVECTION NEAR THE 850 MB FRONTAL BOUNDARY
FROM THE UPPER MS VALLEY INTO NW WI WILL BRING BRING SHRA/TSRA
CHANCES NEAR UPPER MI BUT SHOULD REMAIN SOUTH AND WEST OF THE CWA
THROUGH 12Z/WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 AM EDT TUE SEP 22 2015
THE UPPER JET WILL STRETCH FROM WEST TO EAST ACROSS SOUTHERN CANADA
AT THE START OF THE LONG TERM FORECAST AND WILL REMAIN THAT WAY
THROUGH THE END OF THE WORK WEEK BEFORE RIDGING DEVELOPS OVER
CENTRAL CANADA IN RESPONSE TO A TROUGH DEVELOPING OVER THE PACIFIC
NORTHWEST. THIS WILL LEAD TO A HIGH MOVING FROM THE CANADIAN
PRAIRIES AT THE START OF THE PERIOD...THROUGH ONTARIO...AND THEN
INTO THE NEW ENGLAND STATES BY SUNDAY. WITH THAT SETUP...DRY
CANADIAN AIR AND SUBSIDENCE WILL ATTEMPT TO LIMIT PRECIPITATION
CHANCES OVER MUCH OF THE AREA THROUGH THE PERIOD. THE MAIN
OPPORTUNITY FOR RAIN WILL COME FROM THE BROAD MID LEVEL WARM AIR
ADVECTION THAT DEVELOPS IN MINNESOTA ON TUESDAY NIGHT AND LIFTS
NORTH-NORTHEAST INTO THE MINNESOTA ARROWHEAD AND WESTERN LAKE
SUPERIOR ON WEDNESDAY. MODELS HAVE TRENDED THE BEST FORCING FARTHER
TO THE WEST WHEN COMPARED TO 24HRS AGO AND HAVE DONE THE SAME WITH
THE POP/QPF FORECAST (GREATEST FROM THE FAR NORTHWEST U.P. INTO
LAKE SUPERIOR. STILL THINK THE BROAD WARM AIR ADVECTION COULD LEAD
TO SOME ISOLATED SHOWERS OVER THE CENTRAL U.P. ON WEDNESDAY...BUT
ONLY HAVE SLIGHT CHANCES. MODELS STARTING TO COME INTO BETTER
AGREEMENT ON THE EVOLUTION OF THE SHOWERS AS THE WARM AIR ADVECTION
CONTINUES NORTH AND THEN THE FLOW BECOMES MORE WESTERLY LATER
WEDNESDAY NIGHT INTO THURSDAY OVER NORTHERN LAKE SUPERIOR. THIS
LEADS TO THE FLOW BECOMING MORE PARALLEL TO THE THERMAL GRADIENT AND
IN TURN WEAKENING THE FORCING. WILL FOLLOW THAT IDEA FOR THE
POPS/QPF...SHIFTING IT MORE OVER NORTHERN LAKE SUPERIOR AND THEN
SLOWLY WEAKENING IT AS IT PUSHES EAST. LATEST FORECAST STILL HAS THE
BEST QPF OVER WESTERN LAKE SUPERIOR AND TOWARDS MINNESOTA...WITH
AROUND OR A LITTLE OVER A HALF AN INCH FROM THE KEWEENAW THROUGH
IRONWOOD...THEN TAPERING OFF TO LITTLE OR NOW RAIN OVER THE SOUTH
CENTRAL AND NEAR LAKE MICHIGAN. WHILE INSTABILITY IS FAIRLY LIMITED
(MUCAPE VALUES GENERALLY STAYING BELOW 200 J/KG AND MID LEVEL LAPSE
RATES GENERALLY BELOW 5.5 C/KM)...DID SHOW SLIGHT THUNDER CHANCES
FOR THE WESTERN U.P. AND LAKE SUPERIOR.
MID LEVEL FORCING WEAKENS THURSDAY AFTERNOON INTO FRIDAY MORNING AND
EXPECT A DIMINISHING TREND TO THE SHOWERS. AS THE SURFACE HIGH
SLIDES SOUTHEAST FROM JAMES BAY ON FRIDAY...A RIDGE WILL BECOME
ESTABLISHED OVER THE UPPER GREAT LAKES REGION AND CONTINUE INTO
SATURDAY AS THE HIGH MOVES INTO THE NEW ENGLAND STATES. EXPECT DRIER
AIR TO BECOME ESTABLISHED AND LEAD TO A NICE FALL WEEKEND ACROSS
THE AREA. WITH THE UPPER RIDGE AMPLIFYING OVER CENTRAL CANADA ON
FRIDAY AND SHIFTING INTO EASTERN CANADA ON SATURDAY...WARM
SOUTHWESTERLY FLOW WILL SETUP OVER THE REGION AND PRODUCE ABOVE
NORMAL TEMPERATURES (HIGHS AROUND 10 DEGREES ABOVE NORMAL) FOR THE
WEEKEND. ECMWF/GFS CONTINUE TO SHOW THE AREA BEING BRUSHED BY A
SHORTWAVE MOVING THROUGH SOUTHERN CANADA ON MONDAY AND WILL HAVE
SILENT POPS FOR NOW. LOOKING FARTHER AHEAD...ECMWF ENSEMBLES AND THE
CFS SHOW THE ABOVE NORMAL TEMPERATURES REMAINING THROUGH THE FIRST
WEEK OF OCTOBER AND BOTH INDICATE OCTOBER WILL RECORD ABOVE NORMAL
TEMPERATURES FOR THE MONTH AS A WHOLE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 120 PM EDT TUE SEP 22 2015
ARRIVAL OF DRIER AIR WITH WSHFT TO THE NW FOLLOWING THE COLD FRONT
WILL BRING A RETURN OF VFR CONDITIONS FROM WEST TO EAST EARLY THIS
AFTERNOON. COULD SEE SOME MVFR CONDITIONS LATE WED MORNING AT IWD
WITH SOME SHOWERS IN THE AREA THEN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT TUE SEP 22 2015
AS A COLD FRONT MOVES THROUGH LAKE SUPERIOR...SOUTHWEST WINDS TO 25
KNOTS THIS MORNING WILL DIMINISH TO 15 KNOTS OR LESS THIS AFTERNOON.
WINDS ARE THEN EXPECTED TO REMAIN AT OR BELOW 20 KNOTS THROUGH
SATURDAY AS HIGH PRES SLOWLY MOVES FROM NRN ONTARIO TO QUEBEC.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
730 AM EDT TUE SEP 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE SEP 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL FLOW
FROM THE PAC NW THROUGH SRN CANADA. A VIGOROUS SHORTWAVE TROUGH WAS
LIFTING THROUGH SRN HUDSON BAY WITH ITS TAIL EXTENDING THROUGH NW
ONTARIO TO NRN MN. AT THE SFC...A COLD FRONT STRETCHED FROM JUST
WEST OF JAMES BAY TO THE MN ARROWHEAD. WEAK MID LEVEL QVECTOR CONV
ASSOCIATED WITH THE SHRTWV AND A NARROW RIBBON OF
MOISTURE/INSTABILITY (PWAT TO 1.1 INCHES AND MUCAPE TO AROUND 500
J/KG) SUPPORTED A LINE OF SHRA/TSRA OVER NRN LAKE SUPERIOR. THERE
WERE ONLY ISOLD SHRA FARTHER SW INTO NW WI WHERE THE MID LEVEL
FORCING WAS WEAKER.
TODAY...MODELS SUGGEST THAT THE COLD FRONT WILL MOVE INTO CNTRL
UPPER MI BY AROUND 18Z AND WILL SAG INTO FAR SRN UPPER MI BY 00Z.
WITH ONLY WEAK INSTABILITY AND FORCING ALONG THIS FEATURE...EXPECT
MAINLY JUST ISOLD SHRA/TSRA OVER THE WEST HALF THIS MORNING AND OVER
THE SOUTH AND EAST THIS AFTERNOON. INCREASING CLOUDS ALONG AND AHEAD
OF THE FRONT WILL ALSO LIMIT ANY INCREASE IN INSTABILITY. EVEN WITH
THE GREATER CLOUD COVER...TEMPS WILL AGAIN BE SLIGHTLY ABOVE NORMAL
WITH HIGHS IN THE UPPER 60S TO AROUND 70.
TONIGHT...THERE MAY BE SOME LINGERING SHRA/TSRA OVER THE FAR S CNTRL
IN THE EVENING. OTHERWISE...CLEARING WITH DRIER AIR MOVING IN WILL
ALLOW TEMPS TO FALL INTO THE MID 40S INLAND. EXPECT PATCHY
FOG...MAINLY OVER THE EAST WHERE THE GREATER LOW LEVEL MOISTURE
LINGERS. WAA AND MOISTURE ADVECTION NEAR THE 850 MB FRONTAL BOUNDARY
FROM THE UPPER MS VALLEY INTO NW WI WILL BRING BRING SHRA/TSRA
CHANCES NEAR UPPER MI BUT SHOULD REMAIN SOUTH AND WEST OF THE CWA
THROUGH 12Z/WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 AM EDT TUE SEP 22 2015
THE UPPER JET WILL STRETCH FROM WEST TO EAST ACROSS SOUTHERN CANADA
AT THE START OF THE LONG TERM FORECAST AND WILL REMAIN THAT WAY
THROUGH THE END OF THE WORK WEEK BEFORE RIDGING DEVELOPS OVER
CENTRAL CANADA IN RESPONSE TO A TROUGH DEVELOPING OVER THE PACIFIC
NORTHWEST. THIS WILL LEAD TO A HIGH MOVING FROM THE CANADIAN
PRAIRIES AT THE START OF THE PERIOD...THROUGH ONTARIO...AND THEN
INTO THE NEW ENGLAND STATES BY SUNDAY. WITH THAT SETUP...DRY
CANADIAN AIR AND SUBSIDENCE WILL ATTEMPT TO LIMIT PRECIPITATION
CHANCES OVER MUCH OF THE AREA THROUGH THE PERIOD. THE MAIN
OPPORTUNITY FOR RAIN WILL COME FROM THE BROAD MID LEVEL WARM AIR
ADVECTION THAT DEVELOPS IN MINNESOTA ON TUESDAY NIGHT AND LIFTS
NORTH-NORTHEAST INTO THE MINNESOTA ARROWHEAD AND WESTERN LAKE
SUPERIOR ON WEDNESDAY. MODELS HAVE TRENDED THE BEST FORCING FARTHER
TO THE WEST WHEN COMPARED TO 24HRS AGO AND HAVE DONE THE SAME WITH
THE POP/QPF FORECAST (GREATEST FROM THE FAR NORTHWEST U.P. INTO
LAKE SUPERIOR. STILL THINK THE BROAD WARM AIR ADVECTION COULD LEAD
TO SOME ISOLATED SHOWERS OVER THE CENTRAL U.P. ON WEDNESDAY...BUT
ONLY HAVE SLIGHT CHANCES. MODELS STARTING TO COME INTO BETTER
AGREEMENT ON THE EVOLUTION OF THE SHOWERS AS THE WARM AIR ADVECTION
CONTINUES NORTH AND THEN THE FLOW BECOMES MORE WESTERLY LATER
WEDNESDAY NIGHT INTO THURSDAY OVER NORTHERN LAKE SUPERIOR. THIS
LEADS TO THE FLOW BECOMING MORE PARALLEL TO THE THERMAL GRADIENT AND
IN TURN WEAKENING THE FORCING. WILL FOLLOW THAT IDEA FOR THE
POPS/QPF...SHIFTING IT MORE OVER NORTHERN LAKE SUPERIOR AND THEN
SLOWLY WEAKENING IT AS IT PUSHES EAST. LATEST FORECAST STILL HAS THE
BEST QPF OVER WESTERN LAKE SUPERIOR AND TOWARDS MINNESOTA...WITH
AROUND OR A LITTLE OVER A HALF AN INCH FROM THE KEWEENAW THROUGH
IRONWOOD...THEN TAPERING OFF TO LITTLE OR NOW RAIN OVER THE SOUTH
CENTRAL AND NEAR LAKE MICHIGAN. WHILE INSTABILITY IS FAIRLY LIMITED
(MUCAPE VALUES GENERALLY STAYING BELOW 200 J/KG AND MID LEVEL LAPSE
RATES GENERALLY BELOW 5.5 C/KM)...DID SHOW SLIGHT THUNDER CHANCES
FOR THE WESTERN U.P. AND LAKE SUPERIOR.
MID LEVEL FORCING WEAKENS THURSDAY AFTERNOON INTO FRIDAY MORNING AND
EXPECT A DIMINISHING TREND TO THE SHOWERS. AS THE SURFACE HIGH
SLIDES SOUTHEAST FROM JAMES BAY ON FRIDAY...A RIDGE WILL BECOME
ESTABLISHED OVER THE UPPER GREAT LAKES REGION AND CONTINUE INTO
SATURDAY AS THE HIGH MOVES INTO THE NEW ENGLAND STATES. EXPECT DRIER
AIR TO BECOME ESTABLISHED AND LEAD TO A NICE FALL WEEKEND ACROSS
THE AREA. WITH THE UPPER RIDGE AMPLIFYING OVER CENTRAL CANADA ON
FRIDAY AND SHIFTING INTO EASTERN CANADA ON SATURDAY...WARM
SOUTHWESTERLY FLOW WILL SETUP OVER THE REGION AND PRODUCE ABOVE
NORMAL TEMPERATURES (HIGHS AROUND 10 DEGREES ABOVE NORMAL) FOR THE
WEEKEND. ECMWF/GFS CONTINUE TO SHOW THE AREA BEING BRUSHED BY A
SHORTWAVE MOVING THROUGH SOUTHERN CANADA ON MONDAY AND WILL HAVE
SILENT POPS FOR NOW. LOOKING FARTHER AHEAD...ECMWF ENSEMBLES AND THE
CFS SHOW THE ABOVE NORMAL TEMPERATURES REMAINING THROUGH THE FIRST
WEEK OF OCTOBER AND BOTH INDICATE OCTOBER WILL RECORD ABOVE NORMAL
TEMPERATURES FOR THE MONTH AS A WHOLE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 730 AM EDT TUE SEP 22 2015
LOOK FOR A PERIOD OF MVFR CIGS ALONG AND AHEAD OF A COLD FRONT
MOVING THROUGH UPPER MICHIGAN TODAY. ISOLD -SHRA ARE ALSO EXPECTED
BUT SHOULD NOT BE HEAVY ENOUGH TO REDUCE VSBY. TS ARE POSSIBLE BUT
PROB IS TOO LOW FOR FOR MENTION IN THE TAF. THE ARRIVAL OF DRIER AIR
WITH WSHFT TO THE NW FOLLOWING THE TUE FROPA WILL BRING A RETURN OF
VFR CONDITIONS FROM WEST TO EAST LATE THIS MORNING INTO THIS
AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT TUE SEP 22 2015
AS A COLD FRONT MOVES THROUGH LAKE SUPERIOR...SOUTHWEST WINDS TO 25
KNOTS THIS MORNING WILL DIMINISH TO 15 KNOTS OR LESS THIS AFTERNOON.
WINDS ARE THEN EXPECTED TO REMAIN AT OR BELOW 20 KNOTS THROUGH
SATURDAY AS HIGH PRES SLOWLY MOVES FROM NRN ONTARIO TO QUEBEC.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
515 AM EDT TUE SEP 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE SEP 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL FLOW
FROM THE PAC NW THROUGH SRN CANADA. A VIGOROUS SHORTWAVE TROUGH WAS
LIFTING THROUGH SRN HUDSON BAY WITH ITS TAIL EXTENDING THROUGH NW
ONTARIO TO NRN MN. AT THE SFC...A COLD FRONT STRETCHED FROM JUST
WEST OF JAMES BAY TO THE MN ARROWHEAD. WEAK MID LEVEL QVECTOR CONV
ASSOCIATED WITH THE SHRTWV AND A NARROW RIBBON OF
MOISTURE/INSTABILITY (PWAT TO 1.1 INCHES AND MUCAPE TO AROUND 500
J/KG) SUPPORTED A LINE OF SHRA/TSRA OVER NRN LAKE SUPERIOR. THERE
WERE ONLY ISOLD SHRA FARTHER SW INTO NW WI WHERE THE MID LEVEL
FORCING WAS WEAKER.
TODAY...MODELS SUGGEST THAT THE COLD FRONT WILL MOVE INTO CNTRL
UPPER MI BY AROUND 18Z AND WILL SAG INTO FAR SRN UPPER MI BY 00Z.
WITH ONLY WEAK INSTABILITY AND FORCING ALONG THIS FEATURE...EXPECT
MAINLY JUST ISOLD SHRA/TSRA OVER THE WEST HALF THIS MORNING AND OVER
THE SOUTH AND EAST THIS AFTERNOON. INCREASING CLOUDS ALONG AND AHEAD
OF THE FRONT WILL ALSO LIMIT ANY INCREASE IN INSTABILITY. EVEN WITH
THE GREATER CLOUD COVER...TEMPS WILL AGAIN BE SLIGHTLY ABOVE NORMAL
WITH HIGHS IN THE UPPER 60S TO AROUND 70.
TONIGHT...THERE MAY BE SOME LINGERING SHRA/TSRA OVER THE FAR S CNTRL
IN THE EVENING. OTHERWISE...CLEARING WITH DRIER AIR MOVING IN WILL
ALLOW TEMPS TO FALL INTO THE MID 40S INLAND. EXPECT PATCHY
FOG...MAINLY OVER THE EAST WHERE THE GREATER LOW LEVEL MOISTURE
LINGERS. WAA AND MOISTURE ADVECTION NEAR THE 850 MB FRONTAL BOUNDARY
FROM THE UPPER MS VALLEY INTO NW WI WILL BRING BRING SHRA/TSRA
CHANCES NEAR UPPER MI BUT SHOULD REMAIN SOUTH AND WEST OF THE CWA
THROUGH 12Z/WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 AM EDT TUE SEP 22 2015
THE UPPER JET WILL STRETCH FROM WEST TO EAST ACROSS SOUTHERN CANADA
AT THE START OF THE LONG TERM FORECAST AND WILL REMAIN THAT WAY
THROUGH THE END OF THE WORK WEEK BEFORE RIDGING DEVELOPS OVER
CENTRAL CANADA IN RESPONSE TO A TROUGH DEVELOPING OVER THE PACIFIC
NORTHWEST. THIS WILL LEAD TO A HIGH MOVING FROM THE CANADIAN
PRAIRIES AT THE START OF THE PERIOD...THROUGH ONTARIO...AND THEN
INTO THE NEW ENGLAND STATES BY SUNDAY. WITH THAT SETUP...DRY
CANADIAN AIR AND SUBSIDENCE WILL ATTEMPT TO LIMIT PRECIPITATION
CHANCES OVER MUCH OF THE AREA THROUGH THE PERIOD. THE MAIN
OPPORTUNITY FOR RAIN WILL COME FROM THE BROAD MID LEVEL WARM AIR
ADVECTION THAT DEVELOPS IN MINNESOTA ON TUESDAY NIGHT AND LIFTS
NORTH-NORTHEAST INTO THE MINNESOTA ARROWHEAD AND WESTERN LAKE
SUPERIOR ON WEDNESDAY. MODELS HAVE TRENDED THE BEST FORCING FARTHER
TO THE WEST WHEN COMPARED TO 24HRS AGO AND HAVE DONE THE SAME WITH
THE POP/QPF FORECAST (GREATEST FROM THE FAR NORTHWEST U.P. INTO
LAKE SUPERIOR. STILL THINK THE BROAD WARM AIR ADVECTION COULD LEAD
TO SOME ISOLATED SHOWERS OVER THE CENTRAL U.P. ON WEDNESDAY...BUT
ONLY HAVE SLIGHT CHANCES. MODELS STARTING TO COME INTO BETTER
AGREEMENT ON THE EVOLUTION OF THE SHOWERS AS THE WARM AIR ADVECTION
CONTINUES NORTH AND THEN THE FLOW BECOMES MORE WESTERLY LATER
WEDNESDAY NIGHT INTO THURSDAY OVER NORTHERN LAKE SUPERIOR. THIS
LEADS TO THE FLOW BECOMING MORE PARALLEL TO THE THERMAL GRADIENT AND
IN TURN WEAKENING THE FORCING. WILL FOLLOW THAT IDEA FOR THE
POPS/QPF...SHIFTING IT MORE OVER NORTHERN LAKE SUPERIOR AND THEN
SLOWLY WEAKENING IT AS IT PUSHES EAST. LATEST FORECAST STILL HAS THE
BEST QPF OVER WESTERN LAKE SUPERIOR AND TOWARDS MINNESOTA...WITH
AROUND OR A LITTLE OVER A HALF AN INCH FROM THE KEWEENAW THROUGH
IRONWOOD...THEN TAPERING OFF TO LITTLE OR NOW RAIN OVER THE SOUTH
CENTRAL AND NEAR LAKE MICHIGAN. WHILE INSTABILITY IS FAIRLY LIMITED
(MUCAPE VALUES GENERALLY STAYING BELOW 200 J/KG AND MID LEVEL LAPSE
RATES GENERALLY BELOW 5.5 C/KM)...DID SHOW SLIGHT THUNDER CHANCES
FOR THE WESTERN U.P. AND LAKE SUPERIOR.
MID LEVEL FORCING WEAKENS THURSDAY AFTERNOON INTO FRIDAY MORNING AND
EXPECT A DIMINISHING TREND TO THE SHOWERS. AS THE SURFACE HIGH
SLIDES SOUTHEAST FROM JAMES BAY ON FRIDAY...A RIDGE WILL BECOME
ESTABLISHED OVER THE UPPER GREAT LAKES REGION AND CONTINUE INTO
SATURDAY AS THE HIGH MOVES INTO THE NEW ENGLAND STATES. EXPECT DRIER
AIR TO BECOME ESTABLISHED AND LEAD TO A NICE FALL WEEKEND ACROSS
THE AREA. WITH THE UPPER RIDGE AMPLIFYING OVER CENTRAL CANADA ON
FRIDAY AND SHIFTING INTO EASTERN CANADA ON SATURDAY...WARM
SOUTHWESTERLY FLOW WILL SETUP OVER THE REGION AND PRODUCE ABOVE
NORMAL TEMPERATURES (HIGHS AROUND 10 DEGREES ABOVE NORMAL) FOR THE
WEEKEND. ECMWF/GFS CONTINUE TO SHOW THE AREA BEING BRUSHED BY A
SHORTWAVE MOVING THROUGH SOUTHERN CANADA ON MONDAY AND WILL HAVE
SILENT POPS FOR NOW. LOOKING FARTHER AHEAD...ECMWF ENSEMBLES AND THE
CFS SHOW THE ABOVE NORMAL TEMPERATURES REMAINING THROUGH THE FIRST
WEEK OF OCTOBER AND BOTH INDICATE OCTOBER WILL RECORD ABOVE NORMAL
TEMPERATURES FOR THE MONTH AS A WHOLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 126 AM EDT TUE SEP 22 2015
EXPECT VFR CONDITIONS EARLY IN THE TAF PERIOD AS A GUSTY...
RELATIVELY DRY SW FLOW PERSISTS AHEAD OF AN APRCHG COLD FNT UNDER
SHARP PRES GRADIENT. WHERE SFC WINDS ARE LIKELY TO BE LOWER AT SAW
AND ESPEICALLY THE MORE SHELTERED CMX LOCATION WITH DIURNAL COOLING
ENHANCING THE RADIATION INVRN...THERE WL BE SOME LLWS UNDER THE
SHARP LLJ. A FEW -SHRA AND PERHAPS A TS ALONG WITH MORE CLDS/MVFR
CIGS ARE LIKELY TO PRECEDE THE COLD FNT TOWARD SUNRISE AS MORE LLVL
MSTR SURGES INTO THE AREA. THE ARRIVAL OF DRIER AIR WITH WSHFT TO
THE NW FOLLOWING THE TUE FROPA WL BRING A RETURN OF VFR CONDITIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT TUE SEP 22 2015
AS A COLD FRONT MOVES THROUGH LAKE SUPERIOR...SOUTHWEST WINDS TO 25
KNOTS THIS MORNING WILL DIMINISH TO 15 KNOTS OR LESS THIS AFTERNOON.
WINDS ARE THEN EXPECTED TO REMAIN AT OR BELOW 20 KNOTS THROUGH
SATURDAY AS HIGH PRES SLOWLY MOVES FROM NRN ONTARIO TO QUEBEC.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
502 AM EDT TUE SEP 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE SEP 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL MID/UPPER LEVEL FLOW
FROM THE PAC NW THROUGH SRN CANADA. A VIGOROUS SHORTWAVE TROUGH WAS
LIFTING THROUGH SRN HUDSON BAY WITH ITS TAIL EXTENDING THROUGH NW
ONTARIO TO NRN MN. AT THE SFC...A COLD FRONT STRETCHED FROM JUST
WEST OF JAMES BAY TO THE MN ARROWHEAD. WEAK MID LEVEL QVECTOR CONV
ASSOCIATED WITH THE SHRTWV AND A NARROW RIBBON OF
MOISTURE/INSTABILITY (PWAT TO 1.1 INCHES AND MUCAPE TO AROUND 500
J/KG) SUPPORTED A LINE OF SHRA/TSRA OVER NRN LAKE SUPERIOR. THERE
WERE ONLY ISOLD SHRA FARTHER SW INTO NW WI WHERE THE MID LEVEL
FORCING WAS WEAKER.
TODAY...MODELS SUGGEST THAT THE COLD FRONT WILL MOVE INTO CNTRL
UPPER MI BY AROUND 18Z AND WILL SAG INTO FAR SRN UPPER MI BY 00Z.
WITH ONLY WEAK INSTABILITY AND FORCING ALONG THIS FEATURE...EXPECT
MAINLY JUST ISOLD SHRA/TSRA OVER THE WEST HALF THIS MORNING AND OVER
THE SOUTH AND EAST THIS AFTERNOON. INCREASING CLOUDS ALONG AND AHEAD
OF THE FRONT WILL ALSO LIMIT ANY INCREASE IN INSTABILITY. EVEN WITH
THE GREATER CLOUD COVER...TEMPS WILL AGAIN BE SLIGHTLY ABOVE NORMAL
WITH HIGHS IN THE UPPER 60S TO AROUND 70.
TONIGHT...THERE MAY BE SOME LINGERING SHRA/TSRA OVER THE FAR S CNTRL
IN THE EVENING. OTHERWISE...CLEARING WITH DRIER AIR MOVING IN WILL
ALLOW TEMPS TO FALL INTO THE MID 40S INLAND. EXPECT PATCHY
FOG...MAINLY OVER THE EAST WHERE THE GREATER LOW LEVEL MOISTURE
LINGERS. WAA AND MOISTURE ADVECTION NEAR THE 850 MB FRONTAL BOUNDARY
FROM THE UPPER MS VALLEY INTO NW WI WILL BRING BRING SHRA/TSRA
CHANCES NEAR UPPER MI BUT SHOULD REMAIN SOUTH AND WEST OF THE CWA
THROUGH 12Z/WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 300 AM EDT TUE SEP 22 2015
THE UPPER JET WILL STRETCH FROM WEST TO EAST ACROSS SOUTHERN CANADA
AT THE START OF THE LONG TERM FORECAST AND WILL REMAIN THAT WAY
THROUGH THE END OF THE WORK WEEK BEFORE RIDGING DEVELOPS OVER
CENTRAL CANADA IN RESPONSE TO A TROUGH DEVELOPING OVER THE PACIFIC
NORTHWEST. THIS WILL LEAD TO A HIGH MOVING FROM THE CANADIAN
PRAIRIES AT THE START OF THE PERIOD...THROUGH ONTARIO...AND THEN
INTO THE NEW ENGLAND STATES BY SUNDAY. WITH THAT SETUP...DRY
CANADIAN AIR AND SUBSIDENCE WILL ATTEMPT TO LIMIT PRECIPITATION
CHANCES OVER MUCH OF THE AREA THROUGH THE PERIOD. THE MAIN
OPPORTUNITY FOR RAIN WILL COME FROM THE BROAD MID LEVEL WARM AIR
ADVECTION THAT DEVELOPS IN MINNESOTA ON TUESDAY NIGHT AND LIFTS
NORTH-NORTHEAST INTO THE MINNESOTA ARROWHEAD AND WESTERN LAKE
SUPERIOR ON WEDNESDAY. MODELS HAVE TRENDED THE BEST FORCING FARTHER
TO THE WEST WHEN COMPARED TO 24HRS AGO AND HAVE DONE THE SAME WITH
THE POP/QPF FORECAST (GREATEST FROM THE FAR NORTHWEST U.P. INTO
LAKE SUPERIOR. STILL THINK THE BROAD WARM AIR ADVECTION COULD LEAD
TO SOME ISOLATED SHOWERS OVER THE CENTRAL U.P. ON WEDNESDAY...BUT
ONLY HAVE SLIGHT CHANCES. MODELS STARTING TO COME INTO BETTER
AGREEMENT ON THE EVOLUTION OF THE SHOWERS AS THE WARM AIR ADVECTION
CONTINUES NORTH AND THEN THE FLOW BECOMES MORE WESTERLY LATER
WEDNESDAY NIGHT INTO THURSDAY OVER NORTHERN LAKE SUPERIOR. THIS
LEADS TO THE FLOW BECOMING MORE PARALLEL TO THE THERMAL GRADIENT AND
IN TURN WEAKENING THE FORCING. WILL FOLLOW THAT IDEA FOR THE
POPS/QPF...SHIFTING IT MORE OVER NORTHERN LAKE SUPERIOR AND THEN
SLOWLY WEAKENING IT AS IT PUSHES EAST. LATEST FORECAST STILL HAS THE
BEST QPF OVER WESTERN LAKE SUPERIOR AND TOWARDS MINNESOTA...WITH
AROUND OR A LITTLE OVER A HALF AN INCH FROM THE KEWEENAW THROUGH
IRONWOOD...THEN TAPERING OFF TO LITTLE OR NOW RAIN OVER THE SOUTH
CENTRAL AND NEAR LAKE MICHIGAN. WHILE INSTABILITY IS FAIRLY LIMITED
(MUCAPE VALUES GENERALLY STAYING BELOW 200 J/KG AND MID LEVEL LAPSE
RATES GENERALLY BELOW 5.5 C/KM)...DID SHOW SLIGHT THUNDER CHANCES
FOR THE WESTERN U.P. AND LAKE SUPERIOR.
MID LEVEL FORCING WEAKENS THURSDAY AFTERNOON INTO FRIDAY MORNING AND
EXPECT A DIMINISHING TREND TO THE SHOWERS. AS THE SURFACE HIGH
SLIDES SOUTHEAST FROM JAMES BAY ON FRIDAY...A RIDGE WILL BECOME
ESTABLISHED OVER THE UPPER GREAT LAKES REGION AND CONTINUE INTO
SATURDAY AS THE HIGH MOVES INTO THE NEW ENGLAND STATES. EXPECT DRIER
AIR TO BECOME ESTABLISHED AND LEAD TO A NICE FALL WEEKEND ACROSS
THE AREA. WITH THE UPPER RIDGE AMPLIFYING OVER CENTRAL CANADA ON
FRIDAY AND SHIFTING INTO EASTERN CANADA ON SATURDAY...WARM
SOUTHWESTERLY FLOW WILL SETUP OVER THE REGION AND PRODUCE ABOVE
NORMAL TEMPERATURES (HIGHS AROUND 10 DEGREES ABOVE NORMAL) FOR THE
WEEKEND. ECMWF/GFS CONTINUE TO SHOW THE AREA BEING BRUSHED BY A
SHORTWAVE MOVING THROUGH SOUTHERN CANADA ON MONDAY AND WILL HAVE
SILENT POPS FOR NOW. LOOKING FARTHER AHEAD...ECMWF ENSEMBLES AND THE
CFS SHOW THE ABOVE NORMAL TEMPERATURES REMAINING THROUGH THE FIRST
WEEK OF OCTOBER AND BOTH INDICATE OCTOBER WILL RECORD ABOVE NORMAL
TEMPERATURES FOR THE MONTH AS A WHOLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 126 AM EDT TUE SEP 22 2015
EXPECT VFR CONDITIONS EARLY IN THE TAF PERIOD AS A GUSTY...
RELATIVELY DRY SW FLOW PERSISTS AHEAD OF AN APRCHG COLD FNT UNDER
SHARP PRES GRADIENT. WHERE SFC WINDS ARE LIKELY TO BE LOWER AT SAW
AND ESPEICALLY THE MORE SHELTERED CMX LOCATION WITH DIURNAL COOLING
ENHANCING THE RADIATION INVRN...THERE WL BE SOME LLWS UNDER THE
SHARP LLJ. A FEW -SHRA AND PERHAPS A TS ALONG WITH MORE CLDS/MVFR
CIGS ARE LIKELY TO PRECEDE THE COLD FNT TOWARD SUNRISE AS MORE LLVL
MSTR SURGES INTO THE AREA. THE ARRIVAL OF DRIER AIR WITH WSHFT TO
THE NW FOLLOWING THE TUE FROPA WL BRING A RETURN OF VFR CONDITIONS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 210 PM EDT MON SEP 21 2015
WINDS STAY AT OR BELOW 25 KNOTS FOR THIS ENTIRE FORECAST PERIOD WITH
THE STRONGEST WINDS THIS AFTERNOON THROUGH TUE. HIGH PRESSURE OVER
THE LOWER GREAT LAKES WILL SLOWLY EXIT ACROSS THE NEW ENGLAND AS A
LOW OVER MANITOBA DEEPENS AND LIFTS NE THROUGH HUDSON BAY TONIGHT
THROUGH TUESDAY. AS A RESULT...AN INCREASING PRES GRADIENT WILL
SUPPORT S WINDS IN THE 20-25 KNOT RANGE THROUGH TUESDAY MORNING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...07
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
250 AM EDT TUE SEP 22 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 250 AM EDT TUE SEP 22 2015
HIGH PRESSURE WILL BRING DRY WEATHER INTO NEXT WEEK. HIGHS WILL
BE IN THE 70S AND LOWS IN THE 50S.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 250 AM EDT TUE SEP 22 2015
FAIR WEATHER IS EXPECTED THROUGH THE NEAR TERM AS SFC AND UPPER
RIDGING PREVAILS. A WEAKENING COLD FRONT WITH LIMITED MOISTURE
POOLING AHEAD OF IT WASHES OUT ACROSS NORTHERN LOWER MICHIGAN
TONIGHT AND SFC RIDGING IS REINFORCED ON WEDNESDAY.
AN AREA OF WARM ADVECTION SHOWERS MOVES INTO NORTHERN WISCONSIN
ON WEDNESDAY AND WEDNESDAY NIGHT AND WILL REMAIN WELL NORTH AND
WEST OF THE FORECAST AREA WITH DRY EASTERLY FLOW PREVAILING
THROUGH THURSDAY.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 250 AM EDT TUE SEP 22 2015
DRY AND WARM WEATHER DOMINATES WITH NO LEGITIMATE THREAT FOR
RAINFALL THROUGH AT LEAST NEXT TUESDAY IT APPEARS. WITH SLIGHTLY
HIGHER DEW POINTS BY LATE IN THE WEEK AND MAINLY CLEAR SKIES THERE
COULD BE A THREAT FOR SOME LOCALIZED FOG IN THE MORNINGS...BUT
NOT ENOUGH CONFIDENCE TO ADD TO THE FORECAST.
THE OPERATIONAL GFS IS SHOWING MID 80S BY NEXT TUESDAY WHILE THE 18Z
GFS PARALLEL ENSEMBLE PROBABILITY OF HIGHS > 80 BY THAT TIME IS 70-
90% FOR MUCH OF SW LOWER MI. THIS LEADS TO A GREATER THAN NORMAL
CONFIDENCE IN CONTINUED WARMTH INTO EARLY NEXT WEEK. RIGHT NOW OUR
BLENDED MEDIUM RANGE MODEL GUIDANCE FOR EARLY NEXT WEEK SHOWS HIGHS
GETTING AROUND 80...WHICH SEEMS REASONABLE THIS FAR OUT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EDT TUE SEP 22 2015
MAINTAINED PREVIOUS THINKING IN REGARD TO LIGHT FOG DEVELOPMENT
ACROSS SOUTH CENTRAL LOWER MI. HRRR RUC MODEL SUPPORTS REDUCED
VIS AND PERHAPS EVEN A CIG DEVELOPMENT AT JXN...AND NOT IMPOSSIBLE
THAT LAN MAY HAVE THIS TOO. ADDED 4SM BR TO THE LAN TAF BUT IF JXN
DROPS TO IFR THIS MORNING THEN MAY NEED TO BRING LAN DOWN AS WELL
BASED ON EVOLUTION OF LIGHT FOG AS SHOWN BY THE HRRR RUC.
OTHERWISE...THIS APPEARS TO BE A LOCALIZED ISSUE EARLY THIS
MORNING BUT WILL KEEP MONITORING TRENDS.
&&
.MARINE...
ISSUED AT 250 AM EDT TUE SEP 22 2015
WINDS AND WAVES WILL REMAIN RELATIVELY LIGHT THE NEXT SEVERAL DAYS
AS HIGH PRESSURE PREVAILS.
&&
.HYDROLOGY...
ISSUED AT 1027 AM EDT MON SEP 21 2015
NO PRECIPITATION IS FORECAST THROUGH THROUGH THIS WEEK. RIVER
LEVELS ARE EXPECTED TO HOLD STEADY OR FALL SLOWLY THROUGH THE
WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...HOVING
AVIATION...HOVING
HYDROLOGY...WDM
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
124 AM EDT TUE SEP 22 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 328 PM EDT MON SEP 21 2015
QUIET WEATHER AND MILD TEMPERATURES WILL LIKELY LAST THROUGH NEXT
WEEKEND ACROSS THE AREA. PLENTY OF SUNSHINE IS EXPECTED DURING THE
DAYS WITH HIGHS MAINLY IN THE 70S TO AROUND 80. NIGHTS WILL BE COOL
WITH LOWS IN THE 40S AND 50S.
&&
.UPDATE...
ISSUED AT 1009 PM EDT MON SEP 21 2015
ADDED PATCHY FOG TO THE FORECAST FOR TONIGHT. GOOD RADIATIONAL
COOLING UNDERWAY WITH CLEAR SKIES AND LIGHT WINDS. ALREADY SEEING
SOME FOG DEVELOPING UP AROUND LUDINGTON. HRRR SHOWS ADDITIONAL
PATCHY FOG DEVELOPING OVERNIGHT AS WE COOL OFF ANOTHER COUPLE OF
DEGREES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 328 PM EDT MON SEP 21 2015
WE CONTINUE TO EXPECT A DRY SHORT TERM WITH ABOVE AVERAGE
TEMPERATURES THROUGH THE PERIOD. UPPER RIDGING WILL BE IN CONTROL OF
THE WEATHER OVER THE REGION. THE ONLY ITEM OF NOTE WILL BE A
DISSIPATING COLD FRONT THAT WILL TRY TO SINK IN ACROSS THE AREA TUE
NIGHT INTO WED. IT CONTINUES TO LOOK LIKE THAT MOISTURE WILL BE
LACKING SIGNIFICANTLY...LEADING TO A RAIN-FREE FCST.
WE CAN NOT RULE OUT SOME POSSIBLE PATCHY GROUND FOG OVERNIGHT
TONIGHT. WE WILL NOT PUT IT INTO THE FCST AS IT WOULD BE MAINLY NEAR
BODIES OF WATER...AND LIKELY NOT CAUSE ENOUGH OF AN IMPACT TO
JUSTIFY MENTIONING.
TEMPS LOOK TO BE IN THE 70S EACH DAY WITH H850 TEMPS IN THE LOWER
TEENS C AND PLENTY OF SUNSHINE. LOWS WILL BE IN THE 40S TO LOWER 50S
WITH NEARLY IDEAL RADIATIONAL COOLING CONDITIONS WITH LIGHTER WINDS
AND MAINLY CLEAR SKIES.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 328 PM EDT MON SEP 21 2015
FORECAST IN THE LONG TERM CONTINUES TO FEATURE DRY WEATHER AND ABOVE
NORMAL TEMPERATURES. HAVE NO RAIN IN THE FORECAST WITH HIGHS IN THE
75 TO 80 DEGREE RANGE FOR THE MOST PART.
500MB RIDGING DOMINATES THE LONG TERM...BUT THERE ARE A COUPLE OF
ITEMS TO KEEP AN EYE ON IN AN OTHERWISE QUIET PERIOD. THE FIRST IS
THE COMBINATION OF THE UPPER LOW OFF THE SOUTHERN CALIFORNIA COAST
AND TROPICAL DEPRESSION 16-E WHICH IS MOVING ACROSS NORTHERN MEXICO
AT THIS TIME. THESE TWO FEATURES MERGE TO SOME EXTENT OVER THE
ROCKIES AND MOVE INTO THE PLAINS MID WEEK. AT THIS TIME...THE ECMWF
AND GFS OPERATIONAL AND ENSEMBLE RUNS ALL INDICATE THE RIDGING IN
PLACE ACROSS THE NORTHERN PLAINS AND MIDWEST KEEP THE UPPER LOW AND
ITS MOISTURE WEST OF THE GREAT LAKES OVER THE CENTRAL PLAINS. BOTTOM
LINE...THE SYSTEM SHOULD NOT AFFECT US...STAYING TO THE WEST WHILE
WEAKENING.
THE OTHER ITEM TO WATCH IS EARLY NEXT WEEK ON MONDAY...THE RIDGING
BEGINS TO BREAK DOWN JUST A BIT...VIA THE GFS. THE ECMWF MAINTAINS
THE RIDGE. IF THE GFS VERIFIES...AN APPROACHING FRONT MAY PUSH INTO
THE U.P. IT STILL APPEARS THOUGH THAT THE FRONT AND ITS PRECIP WOULD
BE WELL NORTH OF THE FORECAST AREA.
SO...NEITHER THE MID WEEK UPPER LOW IN THE PLAINS OR THE BREAKING
DOWN OF THE RIDGE VIA THE GFS YIELD ANY PRECIP FOR US...SO CONTINUED
WARM AND DRY WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EDT TUE SEP 22 2015
MAINTAINED PREVIOUS THINKING IN REGARD TO LIGHT FOG DEVELOPMENT
ACROSS SOUTH CENTRAL LOWER MI. HRRR RUC MODEL SUPPORTS REDUCED
VIS AND PERHAPS EVEN A CIG DEVELOPMENT AT JXN...AND NOT IMPOSSIBLE
THAT LAN MAY HAVE THIS TOO. ADDED 4SM BR TO THE LAN TAF BUT IF JXN
DROPS TO IFR THIS MORNING THEN MAY NEED TO BRING LAN DOWN AS WELL
BASED ON EVOLUTION OF LIGHT FOG AS SHOWN BY THE HRRR RUC.
OTHERWISE...THIS APPEARS TO BE A LOCALIZED ISSUE EARLY THIS
MORNING BUT WILL KEEP MONITORING TRENDS.
&&
.MARINE...
ISSUED AT 328 PM EDT MON SEP 21 2015
WE CONTINUE TO EXPECT THAT RATHER TAME CONDITIONS CAN BE EXPECTED
FOR THE NEARSHORE WATERS THROUGH MOST OF THE WEEK AND POTENTIALLY
INTO THE WEEKEND. NO HEADLINES ARE EXPECTED WITH WINDS EXPECTED TO
REMAIN BELOW 20 KNOTS.
&&
.HYDROLOGY...
ISSUED AT 1027 AM EDT MON SEP 21 2015
NO PRECIPITATION IS FORECAST THROUGH THROUGH THIS WEEK. RIVER
LEVELS ARE EXPECTED TO HOLD STEADY OR FALL SLOWLY THROUGH THE
WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MJS
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...DUKE
AVIATION...HOVING
HYDROLOGY...WDM
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS DULUTH MN
708 PM CDT WED SEP 23 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 357 PM CDT WED SEP 23 2015
RAIN CONTINUES INTO THE NIGHT WITH DREARY CONDITIONS PERSISTING INTO
TOMORROW. TEMPERATURES HAVE BEEN COOL TODAY ESPECIALLY ALONG THE
LAKE SUPERIOR COASTLINE WHERE WINDS HAVE BEEN STRONG OFF THE
LAKE...GUSTING TO 25 TO 35 MPH AT TIMES. WARMER TOMORROW...BUT SKIES
REMAIN MOSTLY CLOUDY.
FORECAST WORKED OUT FAIRLY WELL TODAY WITH THE AXIS OF HEAVIEST
PRECIP ABOUT WHERE WE WERE EXPECTING IT. THE FIRST ROUND OF STORMS
TAPERED OFF FASTER THAN ANTICIPATED THIS AFTERNOON...BUT ADDITIONAL
DEVELOPMENT IS ALREADY ONGOING AND ANOTHER WAVE OF WIDESPREAD
RAINFALL IS EXPECTED LATE TONIGHT. WHILE FLASH FLOOD THREAT IS
FAIRLY LOW DUE TO STORM MOTION...SOME URBAN AND SMALL STREAM
FLOODING IS POSSIBLE WITH ANY STORM TONIGHT DUE TO THE EXTREMELY
MOIST NATURE OF THE ATMOSPHERE. PRECIPITABLE WATER VALUES OF 1.0 TO
1.4 ALREADY EXIST ACROSS THE AREA PER RAP/MESOANALYSIS AND EVEN
HIGHER PWATS ARE ABOUT TO BE ADVECTED INTO NORTHWEST WISCONSIN THIS
EVENING AS THE UPPER LOW/SHORTWAVE OVER THE MID MISSOURI VALLEY
GRADUALLY DRIFTS EASTWARD. CURRENT RAP INDICATES PWATS WILL RISE TO
1.4 TO 1.6 INCHES OR HIGHER FROM THE TWIN PORTS AND INTERSTATE 35
CORRIDOR EAST ACROSS PARTS OF NORTHWEST WISCONSIN. THE SOUTH SHORE
OF WISCONSIN IS ESPECIALLY PRIMED FOR POTENTIAL FLOODING AFTER HEAVY
RAINFALL THIS AFTERNOON BROUGHT AROUND TWO INCHES TO MUCH OF
NORTHERN DOUGLAS AND BAYFIELD COUNTIES. WHILE MOST OF THIS RAINFALL
SIMPLY RUNS OFF INTO LAKE SUPERIOR...SATURATED GROUNDS COULD LEAD TO
MINOR FLOODING TONIGHT. WINDS WILL GRADUALLY WEAKEN TONIGHT...BUT
REMAIN GUSTY AT TIMES ALONG THE LAKE SUPERIOR SHORELINE. SOME
PATCHY FOG POSSIBLY ESPECIALLY IN THE BRAINERD LAKES TO LEECH LAKE
AREA WHERE LIGHTER WINDS ARE EXPECTED.
FOR THURSDAY THINGS WILL WIND DOWN AS THE UPPER LOW/SHORTWAVE
DISSIPATES AND A RIDGE BUILDS OVER THE FOUR CORNERS REGION INTO THE
CENTRAL/NORTHERN PLAINS. THE WEAK WARM FRONT CURRENTLY ACROSS
NORTHWEST WISCONSIN WILL GRADUALLY DRIFT SOUTHWARD AND
DISSIPATE...THOUGH LOW LEVEL MOISTURE IS EXPECTED TO REMAIN IN PLACE
THROUGH THE DAY RESULTING IN MOSTLY CLOUDY SKIES. A WEAK SHORTWAVE
TROUGH WILL MOVE ACROSS SOUTHERN MANITOBA INTO NORTHWEST ONTARIO
WHICH COULD RESULT IN A FEW SHOWERS IN NORTHEAST MINNESOTA...AND
WITH THE MOISTURE ALREADY IN PLACE IT MAY NOT TAKE MUCH LIFT TO GET
RAIN/DRIZZLE GOING. TEMPS A LITTLE WARMER DUE TO WARM AIR ADVECTION
TAKING PLACE THROUGH THE DAY...HIGHS IN THE UPPER 50S TO LOW 60S
ACROSS THE MN ARROWHEAD TO MID 60S TO NEAR 70 ELSEWHERE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM CDT WED SEP 23 2015
WEAK UPPER RIDGING BUILDING IN THURSDAY NIGHT INTO FRIDAY WILL BRING
MAINLY DRY CONDITIONS FOR MOST AREAS OF THE NORTHLAND. THERE MAY BE
SOME SHOWERS THAT LINGER OVER FAR NORTHERN MINNESOTA INTO FRIDAY
MORNING. CLOUDS WILL BE SLOW TO DISSIPATE FRIDAY AND WE INCREASED
THEM AND THEY MAY HAVE TO BE INCREASED FURTHER AS SOME OF THE MODELS
ARE SHOWING LOW LEVEL MOISTURE SLOW TO DEPART. HIGHS SHOULD BE FROM
THE UPPER SIXTIES TO LOWER SEVENTIES.
THE NORTHLAND WILL BE BETWEEN DEPARTING HIGH PRESSURE TO THE EAST
AND A COLD FRONT WELL WEST ON SATURDAY. THIS WILL CREATE A WARM
SOUTHERLY FLOW WITH HIGHS IN THE MID TO UPPER SEVENTIES.
THE UPPER FLOW WILL BECOME INCREASINGLY MORE WESTERLY THROUGH THE
WEEKEND INTO EARLY NEXT WEEK PUSHING THE COLD FRONT THROUGH THE
REGION AND SENDING SEVERAL SHORTWAVES THROUGH AS WELL. WE HAVE
CHANCES FOR SHOWERS/STORMS SUNDAY INTO TUESDAY. TEMPERATURES SUNDAY
WILL STILL BE IN THE SEVENTIES THEN FALL INTO THE SIXTIES TUESDAY
AND WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 708 PM CDT WED SEP 23 2015
EXPECTING IFR/LIFR CIGS TO CONTINUE THROUGH MUCH OF THE FORECAST
CYCLE...PER LATEST BUFR SOUNDINGS ALONG WITH MOS GUIDANCE.
OVERNIGHT EXPECTING THE LOWEST CIGS/VISBY AS MORE PRECIPITATION
MOVES THROUGH...WITH LIFR VISBY POSSIBLE AT KBRD AND KDLH. MOST
CONFIDENT IN KDLH AS WINDS WILL BE OUT OF THE EAST.
VISBY WILL GRADUALLY IMPROVE AT ALL TERMINALS AFTER 13-15Z.
HOWEVER STILL KEPT KDLH AND KHIB IN MVFR VISBY BY THE END OF THE
CYCLE...AS A FEW SHOWERS MAY STILL LINGER AROUND. CIGS WILL
IMPROVE TO MVFR/VFR BETWEEN 15-18Z AT KBRD...KINL AND KHYR AS
PRECIPITATION COMES TO AN END.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 51 62 53 69 / 70 70 10 10
INL 48 63 51 71 / 40 30 20 20
BRD 55 68 54 74 / 50 50 10 10
HYR 55 70 51 74 / 60 70 10 10
ASX 53 67 51 70 / 70 60 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR WIZ001.
MN...BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR MNZ037.
LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT THURSDAY FOR LSZ121-140>148.
&&
$$
SHORT TERM...JJM
LONG TERM...MELDE
AVIATION...WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
108 PM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 935 AM CDT TUE SEP 22 2015
MID LEVEL FGEN WAS LEADING TO CLOUDS OVER NORTH DAKOTA INTO
NORTHWEST MINNESOTA AND THE RAP SEEMS TO BE HANDLING THAT AT THIS
TIME. WE INCREASED CLOUD COVER OVER NORTHERN MINNESOTA TODAY BUT
LEFT TEMPERATURES THE SAME AT THIS TIME AS SOME OF THE GUIDANCE
THAT WAS DEPICTING THE CLOUDS WERE CLOSE TO OUR CURRENT MAX TEMP
FORECAST.
THERE WERE ALSO SOME ECHOES SHOWING UP ON AREA RADAR...BUT FEEL
THE DRY LOW-MID LAYER WILL AID IN KEEPING NORTHERN MINNESOTA DRY
THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 334 AM CDT TUE SEP 22 2015
CURRENT SFC OBSERVATIONS SHOW THE COLD FRONT POSITIONED FROM THE
MN ARROWHEAD...TO DULUTH...EXTENDING SOUTHWEST ACROSS CENTRAL
MINNESOTA. RADAR IMAGERY IS SHOWING A FEW LIGHT ECHOES/SHOWERS
AHEAD OF THE FRONT OVER NORTHERN WISCONSIN. HOWEVER...MOST AREAS
HAVE REMAINED DRY OVERNIGHT. THE FRONT WILL CONTINUE TO MARCH
ACROSS NORTHERN WISCONSIN TODAY...BEFORE STALLING OVER CENTRAL WIS
OVERNIGHT. HAVE CONTINUED TO CARRY SMALL POPS FOR AN ISOLATED
SHOWER OR STORM AHEAD OF THE FRONT TODAY.
MEANWHILE...A MUCH COOLER AND DRIER CANADIAN AIR MASS WILL BUILD
INTO NORTHERN MINNESOTA/ONTARIO TODAY AND TONIGHT. THE DRY AIR AND
LIGHT WINDS WILL ALLOW FOR TEMPERATURES TO COOL INTO THE 30S AND 40S
OVERNIGHT. HOWEVER...THERE WILL BE INCREASING HIGH CLOUDS WHICH
WILL HELP MODERATE TEMPS SOME IN THE WESTERN ZONES.
A SHORT WAVE WILL LIFT OVER THE CENTRAL PLAINS WEDNESDAY...PUSHING A
WARM FRONT INTO THE SOUTHERN PORTION OF THE NORTHLAND EARLY
WEDNESDAY MORNING. THE FRONT WILL CONTINUE TO TRACK
NORTH...REACHING THE IRON RANGE/ARROWHEAD REGION WEDNESDAY
AFTERNOON. HAVE ADJUSTED POPS TUESDAY NIGHT/WEDNESDAY FOR
A SLOWER TIMING OF THE WARM FRONT. A RESULTING EASTERLY FLOW WILL
KEEP TEMPERATURES COOL IN THE 50S AND 60S...ALONG WITH CLOUDS AND
RAIN SHOWERS FOR MOST LOCATIONS. PWAT VALUES INCREASE TO OVER 1.5"
DURING THIS TIME...SO PERIOD OF HEAVY RAIN WILL BE POSSIBLE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 334 AM CDT TUE SEP 22 2015
THE BEGINNING OF THE PERIOD WILL LIKELY BE WET. AN ELEVATED
TROUGH/WARM FRONT AND SHORTWAVES ASSOCIATED WITH A CUT OFF LOW IN
THE NORTHERN/CENTRAL PLAINS WILL LIFT THROUGH THE NORTHLAND AND
LIKELY RESULT IN RAIN ACROSS MUCH OF THE FORECAST AREA WEDNESDAY
NIGHT AND THURSDAY. THE LATEST MODELS APPEAR TO BE WETTER AND IN
BETTER AGREEMENT THAN PREVIOUS RUNS...SO INCREASED PCPN CHANCES.
THE PCPN WILL BEGIN TO TAPER OFF THURSDAY AFTERNOON AND THURSDAY
NIGHT AS THE ELEVATED FRONT LIFTS NORTH INTO CANADA AND SURFACE HIGH
PRESSURE IN CANADA NOSES INTO THE NORTHLAND.
AN UPPER LEVEL RIDGE WILL MOVE THROUGH THE NORTHLAND
FRIDAY...PROMOTING SUNNIER SKIES AND WARMER TEMPERATURES. THE RIDGE
WILL FLATTEN FRIDAY NIGHT AND SATURDAY...AND MORE ZONAL FLOW WILL
DEVELOP. THE WARMING TREND WILL CONTINUE SATURDAY AND SUNDAY AS
SOUTHERLY FLOW BRINGS SIGNIFICANTLY WARMER AIR INTO THE REGION.
TEMPERATURES SHOULD REBOUND TO THE LOW TO MIDDLE 70S BY SUNDAY.
A COLD FRONT MIGHT MOVE THROUGH THE NORTHLAND LATE IN THE WEEKEND OR
MONDAY...POSSIBLY BRINGING SHOWERS AND STORMS TO THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 108 PM CDT TUE SEP 22 2015
VFR CONDITIONS WILL PREVAIL AT ALL TERMINALS EARLY ON IN THE TAF
CYCLE. A SHORTWAVE HAS GENERATED SOME HIGH CLOUDS ACROSS
NORTHWESTERN AND NORTHERN MINNESOTA...WHICH WILL MOVE INTO ALL
TERMINALS.
OVERNIGHT MOISTURE WILL ADVECT INTO THE REGION FROM
THE SOUTHWEST...DUE TO A WARM FRONT LIFTING NORTHWARDS. THIS WILL
LOWER CIGS...SPREAD SHOWERS AND POSSIBLY A FEW STORMS INTO ALL
TERMINALS EXCEPT FOR KINL. EXPECTING PRECIP TO HOLD OFF UNTIL
AFTER 18Z AT KINL DUE TO DRIER AIR IN THE LOWER LEVELS...AS
DEPICTED IN THE NAM/GFS/DLHWRF BUFR SOUNDINGS. ALL OTHER TERMINALS
WILL SEE MVFR CIGS/VISBY DEVELOP BETWEEN 12-15Z. FAIRLY CONFIDENT
THAT THERE WILL BE IFR CIGS/VISBY AT SOME POINT AS RAINFALL
BECOMES HEAVY OR A THUNDERSTORM PASSES THROUGH. UNCERTAIN AT THIS
POINT IN TIME ON HOW WIDESPREAD THUNDERSTORM ACTIVITY WILL
BE...AS SOUNDINGS SHOW LOW VALUES OF CAPE TOWARDS THE END OF THE
FORECAST CYCLE WITH MODERATE 0-3 KM LAPSE RATES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 68 49 58 52 / 10 30 80 70
INL 65 42 57 49 / 10 10 40 60
BRD 70 51 63 57 / 10 70 80 70
HYR 70 46 65 56 / 10 40 80 70
ASX 70 47 62 53 / 10 20 70 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...GRANING
LONG TERM...GROCHOCINSKI
AVIATION...WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
942 AM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 935 AM CDT TUE SEP 22 2015
MID LEVEL FGEN WAS LEADING TO CLOUDS OVER NORTH DAKOTA INTO
NORTHWEST MINNESOTA AND THE RAP SEEMS TO BE HANDLING THAT AT THIS
TIME. WE INCREASED CLOUD COVER OVER NORTHERN MINNESOTA TODAY BUT
LEFT TEMPERATURES THE SAME AT THIS TIME AS SOME OF THE GUIDANCE
THAT WAS DEPICTING THE CLOUDS WERE CLOSE TO OUR CURRENT MAX TEMP
FORECAST.
THERE WERE ALSO SOME ECHOES SHOWING UP ON AREA RADAR...BUT FEEL
THE DRY LOW-MID LAYER WILL AID IN KEEPING NORTHERN MINNESOTA DRY
THIS AFTERNOON.
UPDATE ISSUED AT 630 AM CDT TUE SEP 22 2015
UPDATED FOR THE NEW 12Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 334 AM CDT TUE SEP 22 2015
CURRENT SFC OBSERVATIONS SHOW THE COLD FRONT POSITIONED FROM THE
MN ARROWHEAD...TO DULUTH...EXTENDING SOUTHWEST ACROSS CENTRAL
MINNESOTA. RADAR IMAGERY IS SHOWING A FEW LIGHT ECHOES/SHOWERS
AHEAD OF THE FRONT OVER NORTHERN WISCONSIN. HOWEVER...MOST AREAS
HAVE REMAINED DRY OVERNIGHT. THE FRONT WILL CONTINUE TO MARCH
ACROSS NORTHERN WISCONSIN TODAY...BEFORE STALLING OVER CENTRAL WIS
OVERNIGHT. HAVE CONTINUED TO CARRY SMALL POPS FOR AN ISOLATED
SHOWER OR STORM AHEAD OF THE FRONT TODAY.
MEANWHILE...A MUCH COOLER AND DRIER CANADIAN AIR MASS WILL BUILD
INTO NORTHERN MINNESOTA/ONTARIO TODAY AND TONIGHT. THE DRY AIR AND
LIGHT WINDS WILL ALLOW FOR TEMPERATURES TO COOL INTO THE 30S AND 40S
OVERNIGHT. HOWEVER...THERE WILL BE INCREASING HIGH CLOUDS WHICH
WILL HELP MODERATE TEMPS SOME IN THE WESTERN ZONES.
A SHORT WAVE WILL LIFT OVER THE CENTRAL PLAINS WEDNESDAY...PUSHING A
WARM FRONT INTO THE SOUTHERN PORTION OF THE NORTHLAND EARLY
WEDNESDAY MORNING. THE FRONT WILL CONTINUE TO TRACK
NORTH...REACHING THE IRON RANGE/ARROWHEAD REGION WEDNESDAY
AFTERNOON. HAVE ADJUSTED POPS TUESDAY NIGHT/WEDNESDAY FOR
A SLOWER TIMING OF THE WARM FRONT. A RESULTING EASTERLY FLOW WILL
KEEP TEMPERATURES COOL IN THE 50S AND 60S...ALONG WITH CLOUDS AND
RAIN SHOWERS FOR MOST LOCATIONS. PWAT VALUES INCREASE TO OVER 1.5"
DURING THIS TIME...SO PERIOD OF HEAVY RAIN WILL BE POSSIBLE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 334 AM CDT TUE SEP 22 2015
THE BEGINNING OF THE PERIOD WILL LIKELY BE WET. AN ELEVATED
TROUGH/WARM FRONT AND SHORTWAVES ASSOCIATED WITH A CUT OFF LOW IN
THE NORTHERN/CENTRAL PLAINS WILL LIFT THROUGH THE NORTHLAND AND
LIKELY RESULT IN RAIN ACROSS MUCH OF THE FORECAST AREA WEDNESDAY
NIGHT AND THURSDAY. THE LATEST MODELS APPEAR TO BE WETTER AND IN
BETTER AGREEMENT THAN PREVIOUS RUNS...SO INCREASED PCPN CHANCES.
THE PCPN WILL BEGIN TO TAPER OFF THURSDAY AFTERNOON AND THURSDAY
NIGHT AS THE ELEVATED FRONT LIFTS NORTH INTO CANADA AND SURFACE HIGH
PRESSURE IN CANADA NOSES INTO THE NORTHLAND.
AN UPPER LEVEL RIDGE WILL MOVE THROUGH THE NORTHLAND
FRIDAY...PROMOTING SUNNIER SKIES AND WARMER TEMPERATURES. THE RIDGE
WILL FLATTEN FRIDAY NIGHT AND SATURDAY...AND MORE ZONAL FLOW WILL
DEVELOP. THE WARMING TREND WILL CONTINUE SATURDAY AND SUNDAY AS
SOUTHERLY FLOW BRINGS SIGNIFICANTLY WARMER AIR INTO THE REGION.
TEMPERATURES SHOULD REBOUND TO THE LOW TO MIDDLE 70S BY SUNDAY.
A COLD FRONT MIGHT MOVE THROUGH THE NORTHLAND LATE IN THE WEEKEND OR
MONDAY...POSSIBLY BRINGING SHOWERS AND STORMS TO THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 630 AM CDT TUE SEP 22 2015
A COLD FRONT WAS MOVING SE THROUGH NW WISCONSIN EARLY THIS
MORNING. IT SHOULD PASS THROUGH THE KHYR AREA AROUND 9 AM...WITH A
SUBSEQUENT WIND SHIFT TO THE NNW. EXPECT THE MVFR CEILINGS AT KHYR
TO CONTINUE UNTIL THE SKIES CLEAR IN THE WAKE OF THE FRONT.
SAVE FOR THE LINGERING LOW CLOUD COVER IN NW WISCONSIN...SUNNY
SKIES ARE EXPECTED ACROSS THE REGION THIS MORNING. THERE WILL BE
INCREASING HIGH CLOUD COVER THIS AFTERNOON AND EVENING. THERE WILL
BE A NORTHWARD SURGE OF MOISTURE LATER TONIGHT AS A WARM FRONT IN
LIFTS NORTH INTO THE UPPER MIDWEST. THIS WILL BRING LOWERING
CEILINGS OVERNIGHT. RAIN WILL BEGIN TO SPREAD NORTHWARD INTO THE
REGION AFTER MIDNIGHT...FIRST AFFECTING KBRD IN THE WEE HOURS OF
WEDNESDAY MORNING. THE RAIN WILL LIKELY NOT REACH OTHER TERMINALS
UNTIL AFTER 12Z TOMORROW MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 68 49 58 52 / 0 10 80 70
INL 65 42 57 49 / 0 10 40 60
BRD 70 51 63 57 / 10 60 90 70
HYR 70 46 65 56 / 10 10 70 70
ASX 70 47 62 53 / 10 10 70 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 AM CDT THIS MORNING FOR LSZ140.
&&
$$
UPDATE...MELDE
SHORT TERM...GRANING
LONG TERM...GROCHOCINSKI
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1034 AM CDT TUE SEP 22 2015
.UPDATE...
QUIET WEATHER PATTERN TODAY AS SFC RIDGING RESIDES OVER
THE REGION. THE AREA IS SITUATED BETWEEN THE UPPER RIDGE TO THE WEST
AND RETROGRADING UPPER LOW TO THE E...KEEPING VERY DRY NE FLOW ALOFT
LOCKED OVER THE REGION. THIS IS A SIMILAR PATTERN TO WHAT WE SAW LATE
LAST WEEK. THE DRY AIR IS DEPICTED ON THE 12Z REGIONAL SOUNDINGS
WITH AROUND THREE QUARTERS OF AN INCH TO ONE INCH AND A QUARTER PW`S.
DUE TO BETTER MIXING IN THE MODELS...INCLUDING GFS/NAM AND
HRRR...WENT WITH A BLEND OF CURRENT FCST AND HRRR TO LOWER DEWPOINTS
TO ACCOUNT FOR BETTER MIXING. DUE TO LOWER DEWPOINTS AND VERY DRY
CONDITIONS CURRENTLY IN PLACE...DECIDED TO ADD A LIMITED RISK TO FIRE
WEATHER...MAINLY FOR CENTRAL AREAS AND NW DELTA...FOR THIS AFTERNOON
UNTIL 00Z. WINDS LOOK LOW ENOUGH TO NOT SATISFY RED FLAG CRITERIA.
AREAS IN THE E/SE LOOK TO HAVE HIGHER RELATIVE HUMIDITIES DUE TO SOME
ADVECTION OF MOISTURE FROM THE E SO LEFT THOSE AREAS OUT OF THE
LIMITED RISK.
OVERALL...HIGHS LOOK GOOD THIS AFTERNOON AS H85 TEMPS HAVE INCREASED
SOMEWHAT BASED ON 12Z KJAN SOUNDING AND LAPS ANALYSIS. ADJUSTED
HOURLY DEWPOINTS TO ACCOUNT FOR BETTER MIXING. REST OF THE UPDATES
ARE OUT. /DC/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY FOR THE
MOST PART. THE EXCEPTION WILL BE THE POTENTIAL FOR PATCHY AREAS OF
FOG MAINLY IN THE GTR/MEI/HBG CORRIDOR. WITH THE BOUNDARY LAYER
DRYING OUT TODAY...NOT EXPECTING THE SAME DENSITY OF FOG AS SEEN
EARLIER THIS MORNING. /EC/
&&
.PREV DISCUSSION... /ISSUED 344 AM CDT TUE SEP 22 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...WV IMAGERY THIS
MORNING SHOWING WAVE THAT MOVED THROUGH YESTERDAY OVER AL WITH STRONG
SUBSIDENCE IN ITS WAKE OVER S MS/S LA/NORTHERN GULF OF MEXICO.
IMAGERY ALSO SHOWING EVER PRESENT MID LEVEL RIDGE OVER TX/MEXICO WITH
CIRRUS FANNING OUT OVER THE TOP.
MODELS ARE INDICATING THAT THE WAVE OVER AL WILL DIG TO THE S BEFORE
DEPARTING THE AREA WEDNESDAY NIGHT. THE SURFACE REFLECTION OF THE
DIGGING WAVE WILL COME IN THE FORM OF AN INVERTED TROF THAT WILL
DEVELOP OVER AL TODAY. THIS FEATURE WILL THEN BEGIN MOVING WEST WITH
THE PERTURBED WIND FIELD PULLING MOISTURE NORTHWARD ON ITS EASTERN
FLANK TONIGHT. THE TROF AND MOISTURE WILL MOVE ACROSS SOUTH MS
DURING THE AFTERNOON WEDNESDAY WITH THE TROF SLOWLY DAMPENING AS IT
MOVES FURTHER AWAY FROM ITS UPPER SUPPORT. NEVERTHELESS...EXPECT
ISOLATED LIGHT CONVECTION TO DEVELOP DURING THE HEAT OF THE
AFTERNOON. LOW CAPES AND WEAK LAPSE RATES SHOULD KEEP THE CONVECTION
SHALLOW AND IN THE FORM OF SHOWERS. WARMING AIR ALOFT SHOULD PREVENT
THE DEVELOPMENT OF ANY DEEP CONVECTION. THE LIGHT SHOWERS WILL
LINGER INTO THE EVENING OVER THE FAR SOUTH.
WITH THE EXCEPTION OF THE SE ON WEDNESDAY...A SLOW WARMING TREND
WILL BE SEEN IN TEMPS THROUGH THIS PERIOD AS THE MID LEVEL RIDGE
AXIS DRAWS CLOSER. /26/
LONG TERM...THURSDAY THROUGH NEXT MONDAY...MODELS ARE IN FAIRLY
GOOD AGREEMENT WITH KEEPING MID/UPPER LEVEL TROUGHING OVER THE
REGION THROUGHOUT THE LONG TERM PERIOD. MEANWHILE AT THE
SURFACE...HIGH PRESSURE REMAINS WEDGED INTO THE FORECAST AREA FROM
THE NORTHEAST. THIS WILL RESULT IN EASTERLY FLOW PREVAILING ACROSS
THE CWA INTO EARLY NEXT WEEK.
DESPITE THE TROUGHING OVER THE CWA THROUGH THE PERIOD...RAIN CHANCES
WILL REMAIN TOUGH TO COME BY DUE TO THE AFOREMENTIONED SURFACE HIGH
OVER THE REGION...PRECIPITABLE H2O VALUES HOVERING AROUND 1.5
INCHES...AND WEAK EASTERLY FLOW. HOWEVER...AN ISOLATED SHOWER OR
STORM STILL CAN NOT BE RULED OUT DURING THE AFTERNOON. HIGHS THROUGH
THE PERIOD WILL RANGE FROM THE MID 80S TO AROUND 90...AND LOWS EACH
NIGHT WILL FALL INTO THE LOW AND MIDDLE 60S. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 88 60 89 64 / 1 1 15 8
MERIDIAN 86 62 84 64 / 6 2 20 7
VICKSBURG 90 60 91 64 / 1 1 9 6
HATTIESBURG 89 64 85 66 / 4 3 25 14
NATCHEZ 87 62 89 65 / 1 2 11 9
GREENVILLE 88 59 90 64 / 1 1 3 4
GREENWOOD 87 60 88 64 / 1 2 5 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/EC/26/19
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1223 PM CDT TUE SEP 22 2015
.SHORT TERM...(Today and Tonight)
Issued at 0306 AM CDT TUE SEP 22 2015
Surface high pressure extending from northern New England to the
Great Lakes and southwestward into western Kentucky continues to
spread a drier than normal air mass over the eastern half of the
MO Ozarks this morning. A few lower to mid level clouds continued
to develop near the Kansas border as weak upslope flow has
developed where winds have a more southeast direction. The eastern
edge of upper level moisture associated with the remnants of
tropical depression 16E extends across eastern Nebraska southward
into northeast Texas.
These clouds will continue their gradual shift to the east and
should be overspreading our region by this afternoon and through
tonight. While this will slow afternoon heating, we`re already
starting out about 10 degrees warmer than yesterday. Therefore, expect
the net result will be high temperatures pretty similar to
yesterday.
The HRRR shows some weak and scattered precipitation developing
over the area this morning, but will discount that based on latest
trends. The NAM seems to have a better handle of precip but even
it is having a little trouble with overdeveloping precip this
morning. Would not be completely surprised to see a few light
showers develop over our western counties through today, but think
the chances are too low to carry in the forecast at this time.
.LONG TERM...(Wednesday through Monday)
Issued at 0306 AM CDT TUE SEP 22 2015
Still looks like a fairly quiet week weather-wise as the
westerlies remain over the northern Plains and upper Midwest as upper
level ridge builds over the region. The remnants of TD 16-E
gradually get absorbed as a weak wave in the westerlies and tracks
northeast across Nebraska into the eastern Dakotas and Minnesota
through Thursday. Thereafter, the extended models diverge a bit.
The GFS drops the disturbance southward along the eastern edge of
the retrograding upper ridge, and eventually evolves a cutoff low
over Arkansas by Saturday/Sunday. The ECMWF shows a similar trend
but develops the cutoff low further to the west. Will keep a dry
forecast going through Monday, but will need to watch the forecast
trend with this system and may need to add precip if GFS solution
evolves.
Temperatures should be warmest around midweek with the upper ridge
over the area and drop back a few degrees once the ridge shifts
back to the west late this week into the weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1207 PM CDT TUE SEP 22 2015
VFR conditions can be expected though this TAF period. Scattered
to broken cloud decks are expected off and on, but shouldn`t
present much of a problem as much of the cloud cover should be
mid/high level. Winds should remain southerly and generally below
10 knots.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Terry
LONG TERM...Terry
AVIATION...Frye
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
555 AM CDT TUE SEP 22 2015
.SHORT TERM...(Today and Tonight)
Issued at 0306 AM CDT TUE SEP 22 2015
Surface high pressure extending from northern New England to the
Great Lakes and southwestward into western Kentucky continues to
spread a drier than normal air mass over the eastern half of the
MO Ozarks this morning. A few lower to mid level clouds continued
to develop near the Kansas border as weak upslope flow has
developed where winds have a more southeast direction. The eastern
edge of upper level moisture associated with the remnants of
tropical depression 16E extends across eastern Nebraska southward
into northeast Texas.
These clouds will continue their gradual shift to the east and
should be overspreading our region by this afternoon and through
tonight. While this will slow afternoon heating, we`re already
starting out about 10 degrees warmer than yesterday. Therefore, expect
the net result will be high temperatures pretty similar to
yesterday.
The HRRR shows some weak and scattered precipitation developing
over the area this morning, but will discount that based on latest
trends. The NAM seems to have a better handle of precip but even
it is having a little trouble with overdeveloping precip this
morning. Would not be completely surprised to see a few light
showers develop over our western counties through today, but think
the chances are too low to carry in the forecast at this time.
.LONG TERM...(Wednesday through Monday)
Issued at 0306 AM CDT TUE SEP 22 2015
Still looks like a fairly quiet week weather-wise as the
westerlies remain over the northern Plains and upper Midwest as upper
level ridge builds over the region. The remnants of TD 16-E
gradually get absorbed as a weak wave in the westerlies and tracks
northeast across Nebraska into the eastern Dakotas and Minnesota
through Thursday. Thereafter, the extended models diverge a bit.
The GFS drops the disturbance southward along the eastern edge of
the retrograding upper ridge, and eventually evolves a cutoff low
over Arkansas by Saturday/Sunday. The ECMWF shows a similar trend
but develops the cutoff low further to the west. Will keep a dry
forecast going through Monday, but will need to watch the forecast
trend with this system and may need to add precip if GFS solution
evolves.
Temperatures should be warmest around midweek with the upper ridge
over the area and drop back a few degrees once the ridge shifts
back to the west late this week into the weekend.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 0555 AM CDT TUE SEP 22 2015
For the KSGF, KJLN, and KBBG TAFS: VFR conditions are expected
today and tonight. Clouds will increase across the region this
morning and afternoon but will be mainly high level cloud cover.
Winds will pick up some out of the south to southeast this
morning and afternoon then weaken around sunset this evening.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Terry
LONG TERM...Terry
AVIATION...Wise
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
307 AM CDT TUE SEP 22 2015
.SHORT TERM...(Today and Tonight)
Issued at 0306 AM CDT TUE SEP 22 2015
Surface high pressure extending from northern New England to the
Great Lakes and southwestward into western Kentucky continues to
spread a drier than normal air mass over the eastern half of the
MO Ozarks this morning. A few lower to mid level clouds continued
to develop near the Kansas border as weak upslope flow has
developed where winds have a more southeast direction. The eastern
edge of upper level moisture associated with the remnants of
tropical depression 16E extends across eastern Nebraska southward
into northeast Texas.
These clouds will continue their gradual shift to the east and
should be overspreading our region by this afternoon and through
tonight. While this will slow afternoon heating, we`re already
starting out about 10 degrees warmer than yesterday. Therefore, expect
the net result will be high temperatures pretty similar to
yesterday.
The HRRR shows some weak and scattered precipitation developing
over the area this morning, but will discount that based on latest
trends. The NAM seems to have a better handle of precip but even
it is having a little trouble with overdeveloping precip this
morning. Would not be completely surprised to see a few light
showers develop over our western counties through today, but think
the chances are too low to carry in the forecast at this time.
.LONG TERM...(Wednesday through Monday)
Issued at 0306 AM CDT TUE SEP 22 2015
Still looks like a fairly quiet week weather-wise as the
westerlies remain over the northern Plains and upper Midwest as upper
level ridge builds over the region. The remnants of TD 16-E
gradually get absorbed as a weak wave in the westerlies and tracks
northeast across Nebraska into the eastern Dakotas and Minnesota
through Thursday. Thereafter, the extended models diverge a bit.
The GFS drops the disturbance southward along the eastern edge of
the retrograding upper ridge, and eventually evolves a cutoff low
over Arkansas by Saturday/Sunday. The ECMWF shows a similar trend
but develops the cutoff low further to the west. Will keep a dry
forecast going through Monday, but will need to watch the forecast
trend with this system and may need to add precip if GFS solution
evolves.
Temperatures should be warmest around midweek with the upper ridge
over the area and drop back a few degrees once the ridge shifts
back to the west late this week into the weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1142 PM CDT MON SEP 21 2015
Expecting VFR conditions to prevail through the period with upper
level ridge building into the area. May see some mid/high level
cloud cover in the forecast period.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Terry
LONG TERM...Terry
AVIATION...Lindenberg
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
855 PM MDT WED SEP 23 2015
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY...
SENT AN UPDATE TONIGHT TO INCLUDE SOME ISOLATED SPRINKLES OVER OUR
CENTRAL CWA PER THE HRRR AND SOME PATCHY/AREAS OF FOG OVERNIGHT
PER SHORT TERM MODELS AND NEIGHBORING OFFICE CONSENSUS UNTIL
ABOUT 15Z. BMICKELSON
SOME FORECAST CHALLENGES EXIST THIS EVENING...FIRST WITH REGARD
TO WIND SPEEDS FROM GLASGOW SOUTH TO THE FORT PECK LAKE AREA...AND
SECOND WITH REGARD TO LOW STRATUS AND PATCHY FOG OVER THE NORTH
DAKOTA BORDER REGION.
WINDS HAVE BEEN SUSTAINED AROUND 20 MPH MUCH OF THE DAY AROUND
GLASGOW...BUT OBSERVATIONS HAVE BEEN SOMEWHAT LOWER AROUND THE
LAKE AND SO THE DECISION WAS MADE TO HOLD OFF ON A LAKE WIND
ADVISORY DESPITE IT BEING A BREEZY DAY. EAST WINDS ARE EXPECTED TO
RELAX TONIGHT AS AN UPPER RIDGE BUILDS INTO THE REGION AND THE
PRESSURE GRADIENT OVER NORTHEAST MONTANA CONTINUES TO RELAX.
OBSERVATIONS THIS AFTERNOON ARE INDICATIVE OF LOWER CEILINGS AND
VISIBILITY READINGS NEAR SIDNEY AND THESE TRENDS WILL NEED TO BE
MONITORED OVER THE NEXT FEW HOURS. MAY NEED TO INCLUDE MENTION OF
PATCHY FOG INTO THE WEATHER GRIDS...ESPECIALLY EASTERN ZONES...BUT
WILL SEE HOW FAR WEST IT CAN EVOLVE.
THURSDAY LOOKS WARM AND DRY WITH THE UPPER RIDGE BUILDING OVER THE
AREA AND WITH 850MB TEMPERATURES AROUND +25C VIA THE LATEST ECMWF
BY FRIDAY AFTERNOON AHEAD OF AN APPROACHING COLD FRONT...HIGHS ON
FRIDAY COULD BE IN THE MID AND UPPER 80S. A FEW ISOLATED PLACES
MAY COME INTO THE 90S...ESPECIALLY IN THE SOUTHWEST ZONES. THIS
WILL BE NEAR RECORD WARMTH AND SO IS SOMETHING TO KEEP AN EYE ON
IN FUTURE SHIFTS. MALIAWCO
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
CONFIDENCE CONTINUES BELOW THE HIGH LEVEL DURING THIS PERIOD AS
THE UPPER TROUGH MOVES INTO THE PICTURE. LIGHT SPORADIC RAIN
SHOWERS WITH COOLER TEMPERATURES LOOK TO EXPECTED. SOME POP TWEAKS
WERE MADE. TFJ
PREVIOUS DISCUSSION...
EXTENDED FORECAST PERIOD IS FULL OF UNCERTAINTY...ESPECIALLY
REGARDING THE LARGE-SCALE SYNOPTIC WEATHER PATTERN. WITH A RIDGE
OF HIGH PRESSURE IN PLACE OVER THE DESERT SW...THE SW FLOW ALOFT
STREAMING IN FROM THE CALIFORNIA COASTLINE WILL STRUGGLE AGAINST
TROUGHS AND DISTURBANCES MOVING THROUGH THE CANADIAN ROCKIES AND
EVENTUALLY OVER THE NORTHERN HIGH PLAINS AND OUR CWA.
GFS ENSEMBLE AND SPAGHETTI PLOTS SHOW COMPLETE CHAOS AND
UNCERTAINTY AS EARLY AS FRIDAY MORNING AND DEFINITELY FOR THE
ENTIRE USA BY MONDAY MORNING...THE WORST I CAN REMEMBER EVER
SEEING THAT SOON.
AS SUCH...TRIED TO BLEND POPS FOR PRECIP THE BEST I COULD GIVEN
THIS LEVEL OF UNCERTAINTY. BEST CHANCES FOR A PASSING LIGHT RAIN
SHOWER WOULD BE LATE SATURDAY INTO EARLY SUNDAY...THEN AGAIN LATE
SUNDAY THROUGH EARLY MONDAY...BUT OVERALL...THE EC CONTINUES TO
HOLD ONTO A MUCH DRIER SOLUTION...WHILE THE GFS IS QUITE WET.
HERE IS HOPING THAT WE WILL BEGIN TO SEE MUCH BETTER CONSENSUS IN
THE COMING DAYS. BMICKELSON
&&
.AVIATION...
SYNOPSIS: FAST WEST TO SOUTHWEST FLOW ALOFT CONTINUES OVER THE
REGION THROUGH THE PERIOD.
CLOUDS/WX: GUIDANCE IS HINTING AT A RETURN OF MVFR CIGS TO THE
EASTERN STATIONS DURING THE OVERNIGHT HOURS. CURRENTLY THE AREA IS
MOVING OFF TO EAST-NORTHEAST. WILL CONTINUE TO MONITOR IF IT SHOWS
RETROGRESSION BACK TOWARDS THE AREA...THEN WILL RE-EVALUATE THE
FORECAST FOR THE OVERNIGHT HOURS. FOR NOW WILL STICK WITH VFR.
WIND: EAST WIND WILL CONTINUE TO DIMINISH AND BECOME LIGHT AND
VARIABLE OVERNIGHT LASTING INTO TOMORROW. PROTON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
843 PM MDT WED SEP 23 2015
.UPDATE...
A QUIET NIGHT IS IN STORE ACROSS THE FORECAST AREA AND THE
CURRENT FORECAST HAS THIS WELL COVERED. SATELLITE SHOWING MOSTLY
CLEAR SKIES ACROSS OUR FORECAST AREA WITH JUST A FEW CLOUDS AROUND
AT TIMES. IN ANY CASE...A MOSTLY CLEAR NIGHT IS EXPECTED.
HOWEVER...LATEST MAV AND MET GUIDANCE IS SHOWING VERY LOW
TEMPERATURE/DEWPOINT SPREADS BEGINNING AFTER MIDNIGHT. IN
ADDITION...THE HRRR MODEL IS SHOWING LOW LEVEL MOISTURE MOVING
WEST FROM THE DAKOTAS LATE TONIGHT AS WELL. AS A RESULT...I ADDED
PATCHY FOG FROM THE EASTERN HALF OF CUSTER AND POWDER RIVER
COUNTIES EASTWARD TO THE DAKOTA BORDERS FROM ABOUT MIDNIGHT
THROUGH MID MORNING THURSDAY. UPDATED FORECAST HAS BEEN SENT.
HOOLEY
&&
.SHORT TERM...VALID FOR THU AND FRI...
WARM AND DRY WEATHER WILL CONTINUE THROUGH THE SHORT TERM PERIOD
AS STRONG UPPER LEVEL RIDGE REMAINS THE DOMINANT FEATURE. WE ARE
SEEING SLOW HEIGHT RISES TODAY AND THIS WILL TRANSLATE TO A
WARMING TREND TOMORROW AND FRIDAY. EXPECT HIGHS INTO THE 80S
ACROSS OUR CWA ON THURSDAY. FOR FRIDAY...700MB PLUME TO NEAR +13C
ALONG WITH DRY AIR AND DEEP MIXING WILL SUPPORT TEMPS OF 90F OR
MORE FOR MANY LOCATIONS. HAVE RAISED FORECAST HIGHS A LITTLE MORE
FOR FRIDAY. DAILY RECORDS COULD BE CHALLENGED AT LIVINGSTON...
BILLINGS AND SHERIDAN. IRONICALLY ALL OF THESE RECORDS WERE SET OR
TIED IN 2014.
AXIS OF HIGHER THETA-E AIR EXISTS OVER EASTERN MT TODAY BUT WITH
CAPPED INSTABILITY...100-300 J/KG OF SBCIN PER THE LATEST
MESOANALYSIS. SOME OF THE LATEST HIGH RES MODELS PRODUCE A LITTLE
CONVECTION TO OUR NORTH AND NORTHEAST...OUTSIDE OF OUR CWA...AND
THIS SEEMS REASONABLE AS WE CONTINUE TO UNDERGO HEIGHT RISES...
WITH LOWEST LIFTED INDICES IN THE WESTERN DAKOTAS BY 00Z. THIS IS
SOMETHING TO WATCH BUT FOR NOW AM COMFORTABLE IN KEEPING OUR
EASTERN AREAS DRY LATE THIS AFTERNOON AND EVENING.
FIRE WEATHER CONCERNS WILL BE ELEVATED ON FRIDAY PARTICULARLY IN
OUR WEST AS ONSET OF HEIGHT FALLS IN RESPONSE TO TROF ALONG THE
PACIFIC COAST WILL RESULT IN INCREASING SOUTHWESTERLY MID LEVEL
FLOW. SHOULD SEE MIXED GUSTS OF 20-30 MPH IN OUR WEST AT PLACES
SUCH AS LIVINGSTON. IN ADDITION...WEAK SHORTWAVE COMBINED WITH
STEEP LAPSE RATES AND A LITTLE MID LEVEL MOISTENING MAY YIELD A
FEW HIGH-BASED SHOWERS OR WEAK/DRY THUNDERSTORMS IN OUR WEST BY
FRIDAY EVENING. WILL INTRODUCE ISOLD DRY TSTMS TO LOCATIONS FROM
LIVINGSTON TO HARLOWTON FRIDAY EVENING...AND EVEN SOME VIRGA OR
SPRINKLES COULD CREATE SOME ERRATIC DOWNDRAFT WINDS. AND LETS NOT
FORGET THE 90 DEGREE TEMPS AND MIN RHS OF 10-15 PERCENT. WILL
HIGHLIGHT ALL OF THIS IN OUR FIRE WEATHER FORECAST. IN CENTRAL AND
EASTERN ZONES THE MIXED WIND POTENTIAL IS LOWER...WITHOUT THE RISK
OF DRY TSTMS.
WEAK COLD FRONT WILL BEGIN TO PUSH INTO OUR AREA LATE FRIDAY
NIGHT. THIS SHOULD BE A DRY FROPA WITHOUT A SIGNIFICANT WIND
SHIFT...WHICH MAY NOT REACH OUR EASTERN PARTS BY 12Z SATURDAY.
JKL
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MODELS HAVE COME INTO A LITTLE BETTER AGREEMENT FOR THE START OF
NEXT WEEK BUT THERE STILL CONTINUES TO MANY DIFFERENCES IN THE
HANDLING OF OUR NEXT POTENTIAL RAIN MAKER ON MONDAY AND TUESDAY.
LONG TERM BEGINS WITH UPPER LEVEL RIDGING DEPARTING THE AREA TO
THE EAST. IN ITS WAKE A TROUGH WILL SLIDE THROUGH PARTS OF
SOUTHERN CANADA THIS WEEKEND WHICH WILL MOVE A SERIES OF FRONTS
THROUGH THE FORECAST AREA. THESE FRONTS WILL BRING SLIGHT CHANCES
OF RAIN TO THE AREA BUT WITH A LACK OF SIGNIFICANT FORCING ALOFT
NOT EXPECTING MUCH RAIN. THESE FRONTS WILL COOL CONDITIONS OFF TO
NEAR SEASONABLE LEVELS AFTER A HOT END TO THE WEEK.
MODELS CONTINUE TO MAINTAIN LARGE DEVIATIONS IN THE HANDLING OF
AN UPPER LEVEL LOW JUST OFF THE WESTERN CONUS LATE THIS WEEKEND.
THE EURO IS MUCH SLOWER IN EJECTING THIS LOW EASTWARDS AND THUS
KEEPS THE AREA MOSTLY DRY AND WARM MONDAY THROUGH WEDNESDAY. WHILE
THE GFS IS A LITTLE MORE PROGRESSIVE...WETTER...AND MUCH COOLER AS
IT MOVES A STRONGER UPPER LOW THROUGH THE AREA. 12Z EURO RUN WAS A
LITTLE MORE WET AND A LITTLE LESS AGGRESSIVE WITH THE POST FRONTAL
RIDGING EARLY NEXT WEEK SO LEANED A LITTLE MORE TOWARDS THE
CONSISTENT GFS. HOWEVER...WITH MANY DIFFERENCES STILL TOOK A
MOSTLY EVEN BLEND OF THE TWO SOLUTIONS AND CLIMATOLOGY FOR NOW
UNTIL WE CAN GET A LITTLE MORE AGREEMENT FOR EARLY NEXT WEEK.
DOBBS
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS MOST TERMINALS TONIGHT THROUGH
THURSDAY AFTERNOON... WITH MOSTLY CLEAR SKIES AND LIGHT AND
VARIABLE WINDS DOMINATING. THE EXCEPTION MAY AGAIN BE KMLS IN THE
EARLY MORNING TIMEFRAME... AS THESE CONDITIONS MAY LEAD TO ENOUGH
COOLING TO SATURATE THE LOWEST 300 FEET OR SO...AS PER NAM
GUIDANCE AND RECENT TRENDS IN RAP GUIDANCE. MODEL AGREEMENT ON
LOCATION AND TIMING OF FOG SEEMS TO BE INCREASING BUT PREDICTED
VISIBILITY GRADIENTS ASSOCIATED WITH THE FOG ARE TIGHT RIGHT IN
THE VICINITY OF KMLS...HAVE THUS OPTED FOR VCFG IN THE TAF FOR NOW
THOUGH VISIBILITIES COULD FALL BELOW 3 MILES DEPENDING ON EXACT
PLACEMENT OF AFOREMENTIONED GRADIENT. MROWELL/HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 052/084 055/091 058/084 054/074 053/074 050/069 047/073
00/U 00/U 12/W 22/W 22/W 22/W 21/B
LVM 046/083 049/089 051/084 048/075 047/074 047/068 044/072
00/U 01/N 11/B 12/W 22/W 22/W 21/B
HDN 047/086 049/094 053/087 051/077 050/076 047/072 044/075
00/U 00/U 11/B 12/W 22/W 22/W 11/B
MLS 050/085 056/092 056/086 053/075 052/075 048/072 045/073
00/U 00/U 01/B 12/W 21/B 22/W 21/B
4BQ 050/086 053/090 055/088 054/077 052/078 049/074 046/075
00/U 00/U 00/B 12/W 22/W 22/W 21/B
BHK 049/081 053/085 054/086 053/074 049/072 046/069 045/069
00/U 00/N 00/B 12/W 21/B 22/W 21/B
SHR 046/087 049/091 051/088 052/078 050/078 047/076 044/077
00/U 00/U 01/B 12/W 22/W 22/W 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1241 PM CDT TUE SEP 22 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
FORECAST CONCERNS TODAY WILL BE ANY STRATUS/FOG/POTENTIAL FOR
DENSE FOG ADVISORY...AND INCREASING SHOWER/THUNDERSTORM CHANCES.
THE H5 PATTERN HAD A STRONG AREA OF LOW PRESSURE OVER HUDSON BAY
WITH WESTERLY FLOW FROM THE PACIFIC NORTHWEST INTO THE NORTHERN
PLAINS. THE H5 RIDGE WAS ACROSS THE SOUTHERN PLAINS...HOWEVER A
TROUGH OVER THE EASTERN U.S. AND REMNANTS OF THE TROPICAL
DEPRESSION OVER THE SOUTHWEST U.S.
WATER VAPOR IMAGERY AND LIGHTNING DATA SHOWED THE ACTIVE WEATHER
ASSOCIATED WITH THE FRONT OVER THE NORTHERN ROCKIES/PLAINS INTO
ONTARIO AND WITH THE TROUGH IN THE SOUTHEAST U.S. DEEP MOISTURE FROM
THE TROPICAL DEPRESSION EXTENDED INTO THE SOUTHWEST U.S.AND ROCKIES
INTO TEXAS AND ACROSS MEXICO. THE LATEST WSR-88D RADAR MOSAIC
SHOWED SHOWERS AND A FEW ISOLATED THUNDERSTORMS OVER NORTH CENTRAL
KANSAS.
LOCALLY...SOME OF THE CIRRUS WAS SPREADING INTO THE PLAINS FROM THE
SOUTHWEST U.S. OUR 00Z SOUNDING HAD DRIED OUT FROM H85 AND
ABOVE...HOWEVER THERE WAS DEEP MOISTURE BELOW THIS LAYER...
ACCOUNTING FOR THE PWAT OF 0.92 OF AN INCH. SURFACE METARS
REVEALED FOG...SOME DENSE AT 08Z WITH DEWPOINTS IN THE 50S TO
LOWER 60S.
THIS MORNING...THE SURFACE FRONT IS LOCATED NORTH OF MITCHEL SOUTH
DAKOTA AND O NEILL NEBRASKA. SURFACE DEWPOINTS ARE IN THE LOWER
60S AND DEPRESSIONS WILL REMAIN LOW. AREAS OF FOG ARE FAVORED
THROUGH 18Z...SOME DENSE...LASTING INTO THE AFTERNOON IN NORTHEAST
NEBRASKA. THE RAP HAS THE FOCUS OF DENSE FOG IN NORTHEAST NEBRASKA
AND MAY NEED TO CONSIDER A DENSE FOG ADVISORY. FOR NOW WILL
MENTION PATCHY DENSE FOG IN THE ZONES.
THE SHORT TERM MODELS ARE IN GOOD AGREEMENT THAT THE 585DM HEIGHTS
WILL INCREASE TO 588DM TODAY WITH STEEPENING MID LEVEL LAPSE RATES.
HEIGHTS LOWER OVER COLORADO AS AN H5 SPEED MAX APPROACHES AND OMEGA
INCREASES. AS THIS OCCURS...THERE IS A DOUBLE FRONT STRUCTURE WITH
THE COOLER EASTERLY FLOW ACROSS SOUTH DAKOTA AND THE WARMER AIR
ACROSS KANSAS INTO SOUTHERN NEBRASKA. WILL HOLD TEMPERATURES IN
THE 70S NORTH...WITH MID 80S IN THE SOUTH. WARM AIR ADVECTION OVER
THE FRONT AND CONVERGENCE IN THE NORTH COULD LEAD TO ISOLATED
SHOWERS/TSHOWER. THE RAP/HRRR SEEM TO FOCUS OVER THE CENTRAL AND
SOUTHERN PARTS OF THE FORECAST AREA WHILE THE NAM IS FARTHER
NORTH AND IN SOUTHWEST IOWA. LOW CONFIDENCE IN EXACT
LOCATION...BUT WILL MAINTAIN A LOW POP.
TONIGHT...THE OPEN TROUGH OVER THE ROCKIES CLOSES OFF
WITH OMEGA INCREASING TO THE WEST AND TO THE NORTH. WITH THE
DOUBLE FRONT STRUCTURE THERE COULD BE A COUPLE OF AREAS OF
PRECIPITATION. THE PRECIPITATION BECOMES EVEN MORE ORGANIZED
WEDNESDAY INTO WEDNESDAY NIGHT WITH RAIN BECOMING LIKELY. WITH A
CHANCE FOR SHOWERS AND THUNDERSTORMS THURSDAY. WE ARE OUTLOOKED IN
THE EXCESSIVE RAIN AREA FOR DAY THREE (WED/WED NIGHT)...BUT WILL
NEED TO SEE HOW THE STORM SYSTEM EVOLVES UNTIL THEN.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
AT THE BEGINNING OF THE EXTENDED...THE TROPICAL REMNANTS CONTINUE
TO AFFECT THE AREA...MORESO WITH THE EC COMPARED TO THE
NAM/GFS. LINGERED A SLIGHT CHANCE FOR SHOWERS THURSDAY NIGHT WITH
DRY WEATHER FOR MUCH OF THE REST OF THE EXTENDED WITH MID LEVEL
RIDGING. TEMPERATURES SHOULD BE NEAR TO 5 TO 10 DEGREES ABOVE
NORMAL IN THE 70S TO LOWER 80S.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1231 PM CDT TUE SEP 22 2015
AS OF 17Z SOME LIFR CIGS LINGER MAINLY WEST OF THE KOFK REGION.
THIS LOW CLOUD DECK WAS SLOWLY ERODING. KOFK HAD ALREADY GONE TO
MVFR CIGS. VCTS JUST SOUTH OF KLNK AND IT APPEARS IT WILL REMAIN
SOUTH AND MOVE OFF TO THE EAST. ALL THREE TAF SITES THEN REMAIN
RELATIVELY QUIET UNTIL LATER IN THE FORECAST PERIOD. AFTER 10Z
EXPECT ADDITIONAL THUNDERSTORM DEVELOPMENT AND ALL THREE SITES
HAVE TEMPO PERIODS TO REFLECT THIS AND TREND THAT DIRECTION.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...MEYER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
627 AM CDT TUE SEP 22 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
FORECAST CONCERNS TODAY WILL BE ANY STRATUS/FOG/POTENTIAL FOR
DENSE FOG ADVISORY...CHANCE FOR LIGHT PRECIPITATION...THEN
INCREASING SHOWER/THUNDERSTORM CHANCES.
THE H5 PATTERN HAD A STRONG AREA OF LOW PRESSURE OVER HUDSON BAY
WITH WESTERLY FLOW FROM THE PACIFIC NORTHWEST INTO THE NORTHERN
PLAINS. THE H5 RIDGE WAS ACROSS THE SOUTHERN PLAINS...HOWEVER A
TROUGH OVER THE EASTERN U.S. AND REMNANTS OF THE TROPICAL
DEPRESSION OVER THE SOUTHWEST U.S.
WATER VAPOR IMAGERY AND LIGHTNING DATA SHOWED THE ACTIVE WEATHER
ASSOCIATED WITH THE FRONT OVER THE NORTHERN ROCKIES/PLAINS INTO
ONTARIO AND WITH THE TROUGH IN THE SOUTHEAST U.S. DEEP MOISTURE FROM
THE TROPICAL DEPRESSION EXTENDED INTO THE SOUTHWEST U.S.AND ROCKIES
INTO TEXAS AND ACROSS MEXICO. THE LATEST WSR-88D RADAR MOSAIC
SHOWED SHOWERS AND A FEW ISOLATED THUNDERSTORMS OVER NORTH CENTRAL
KANSAS.
LOCALLY...SOME OF THE CIRRUS WAS SPREADING INTO THE PLAINS FROM THE
SOUTHWEST U.S. OUR 00Z SOUNDING HAD DRIED OUT FROM H85 AND
ABOVE...HOWEVER THERE WAS DEEP MOISTURE BELOW THIS LAYER...
ACCOUNTING FOR THE PWAT OF 0.92 OF AN INCH. SURFACE METARS
REVEALED FOG...SOME DENSE AT 08Z WITH DEWPOINTS IN THE 50S TO
LOWER 60S.
THIS MORNING...THE SURFACE FRONT IS LOCATED NORTH OF MITCHEL SOUTH
DAKOTA AND O NEILL NEBRASKA. SURFACE DEWPOINTS ARE IN THE LOWER
60S AND DEPRESSIONS WILL REMAIN LOW. AREAS OF FOG ARE FAVORED
THROUGH 18Z...SOME DENSE...LASTING INTO THE AFTERNOON IN NORTHEAST
NEBRASKA. THE RAP HAS THE FOCUS OF DENSE FOG IN NORTHEAST NEBRASKA
AND MAY NEED TO CONSIDER A DENSE FOG ADVISORY. FOR NOW WILL
MENTION PATCHY DENSE FOG IN THE ZONES.
THE SHORT TERM MODELS ARE IN GOOD AGREEMENT THAT THE 585DM HEIGHTS
WILL INCREASE TO 588DM TODAY WITH STEEPENING MID LEVEL LAPSE RATES.
HEIGHTS LOWER OVER COLORADO AS AN H5 SPEED MAX APPROACHES AND OMEGA
INCREASES. AS THIS OCCURS...THERE IS A DOUBLE FRONT STRUCTURE WITH
THE COOLER EASTERLY FLOW ACROSS SOUTH DAKOTA AND THE WARMER AIR
ACROSS KANSAS INTO SOUTHERN NEBRASKA. WILL HOLD TEMPERATURES IN
THE 70S NORTH...WITH MID 80S IN THE SOUTH. WARM AIR ADVECTION OVER
THE FRONT AND CONVERGENCE IN THE NORTH COULD LEAD TO ISOLATED
SHOWERS/TSHOWER. THE RAP/HRRR SEEM TO FOCUS OVER THE CENTRAL AND
SOUTHERN PARTS OF THE FORECAST AREA WHILE THE NAM IS FARTHER
NORTH AND IN SOUTHWEST IOWA. LOW CONFIDENCE IN EXACT
LOCATION...BUT WILL MAINTAIN A LOW POP.
TONIGHT...THE OPEN TROUGH OVER THE ROCKIES CLOSES OFF
WITH OMEGA INCREASING TO THE WEST AND TO THE NORTH. WITH THE
DOUBLE FRONT STRUCTURE THERE COULD BE A COUPLE OF AREAS OF
PRECIPITATION. THE PRECIPITATION BECOMES EVEN MORE ORGANIZED
WEDNESDAY INTO WEDNESDAY NIGHT WITH RAIN BECOMING LIKELY. WITH A
CHANCE FOR SHOWERS AND THUNDERSTORMS THURSDAY. WE ARE OUTLOOKED IN
THE EXCESSIVE RAIN AREA FOR DAY THREE (WED/WED NIGHT)...BUT WILL
NEED TO SEE HOW THE STORM SYSTEM EVOLVES UNTIL THEN.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
AT THE BEGINNING OF THE EXTENDED...THE TROPICAL REMNANTS CONTINUE
TO AFFECT THE AREA...MORESO WITH THE EC COMPARED TO THE
NAM/GFS. LINGERED A SLIGHT CHANCE FOR SHOWERS THURSDAY NIGHT WITH
DRY WEATHER FOR MUCH OF THE REST OF THE EXTENDED WITH MID LEVEL
RIDGING. TEMPERATURES SHOULD BE NEAR TO 5 TO 10 DEGREES ABOVE
NORMAL IN THE 70S TO LOWER 80S.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 626 AM CDT TUE SEP 22 2015
AREAS OF LIFR CIGS/VSBYS IN NORTHEAST NEBRASKA WILL ONLY SLOWLY
IMPROVE THROUGH THE MORNING NEAR KOFK. EXPECT AT LEAST IFR
CONDITIONS THROUGH ABOUT 16Z BEFORE CIGS LIFT AND VSBYS IMPROVE TO
VFR BY OR SHORTLY AFTER 18Z. MVFR FOG IS LIKELY AT KLNK AND KOMA
THROUGH MID MORNING...AND THERE IS A SMALL CHANCE IFR CIGS/VSBYS
COULD DEVELOP FOR A SHORT TIME AS WELL. OTHERWISE VFR CONDITIONS ARE
FORECAST THROUGH THE AFTERNOON AND EVENING. THERE IS A SMALL CHANCE
FOR THUNDERSTORMS TO DEVELOP AT ALL TAF SITES DURING THE LATE
AFTERNOON OR EVENING. BUT THUNDERSTORMS ARE MORE LIKELY AFTER 06Z IN
NORTHEAST NEBRASKA AS A LOW PRESSURE SYSTEM APPROACHES THAT AREA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
357 AM CDT TUE SEP 22 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
FORECAST CONCERNS TODAY WILL BE ANY STRATUS/FOG/POTENTIAL FOR
DENSE FOG ADVISORY...CHANCE FOR LIGHT PRECIPITATION...THEN
INCREASING SHOWER/THUNDERSTORM CHANCES.
THE H5 PATTERN HAD A STRONG AREA OF LOW PRESSURE OVER HUDSON BAY
WITH WESTERLY FLOW FROM THE PACIFIC NORTHWEST INTO THE NORTHERN
PLAINS. THE H5 RIDGE WAS ACROSS THE SOUTHERN PLAINS...HOWEVER A
TROUGH OVER THE EASTERN U.S. AND REMNANTS OF THE TROPICAL
DEPRESSION OVER THE SOUTHWEST U.S.
WATER VAPOR IMAGERY AND LIGHTNING DATA SHOWED THE ACTIVE WEATHER
ASSOCIATED WITH THE FRONT OVER THE NORTHERN ROCKIES/PLAINS INTO
ONTARIO AND WITH THE TROUGH IN THE SOUTHEAST U.S. DEEP MOISTURE FROM
THE TROPICAL DEPRESSION EXTENDED INTO THE SOUTHWEST U.S.AND ROCKIES
INTO TEXAS AND ACROSS MEXICO. THE LATEST WSR-88D RADAR MOSAIC
SHOWED SHOWERS AND A FEW ISOLATED THUNDERSTORMS OVER NORTH CENTRAL
KANSAS.
LOCALLY...SOME OF THE CIRRUS WAS SPREADING INTO THE PLAINS FROM THE
SOUTHWEST U.S. OUR 00Z SOUNDING HAD DRIED OUT FROM H85 AND
ABOVE...HOWEVER THERE WAS DEEP MOISTURE BELOW THIS LAYER...
ACCOUNTING FOR THE PWAT OF 0.92 OF AN INCH. SURFACE METARS
REVEALED FOG...SOME DENSE AT 08Z WITH DEWPOINTS IN THE 50S TO
LOWER 60S.
THIS MORNING...THE SURFACE FRONT IS LOCATED NORTH OF MITCHEL SOUTH
DAKOTA AND O NEILL NEBRASKA. SURFACE DEWPOINTS ARE IN THE LOWER
60S AND DEPRESSIONS WILL REMAIN LOW. AREAS OF FOG ARE FAVORED
THROUGH 18Z...SOME DENSE...LASTING INTO THE AFTERNOON IN NORTHEAST
NEBRASKA. THE RAP HAS THE FOCUS OF DENSE FOG IN NORTHEAST NEBRASKA
AND MAY NEED TO CONSIDER A DENSE FOG ADVISORY. FOR NOW WILL
MENTION PATCHY DENSE FOG IN THE ZONES.
THE SHORT TERM MODELS ARE IN GOOD AGREEMENT THAT THE 585DM HEIGHTS
WILL INCREASE TO 588DM TODAY WITH STEEPENING MID LEVEL LAPSE RATES.
HEIGHTS LOWER OVER COLORADO AS AN H5 SPEED MAX APPROACHES AND OMEGA
INCREASES. AS THIS OCCURS...THERE IS A DOUBLE FRONT STRUCTURE WITH
THE COOLER EASTERLY FLOW ACROSS SOUTH DAKOTA AND THE WARMER AIR
ACROSS KANSAS INTO SOUTHERN NEBRASKA. WILL HOLD TEMPERATURES IN
THE 70S NORTH...WITH MID 80S IN THE SOUTH. WARM AIR ADVECTION OVER
THE FRONT AND CONVERGENCE IN THE NORTH COULD LEAD TO ISOLATED
SHOWERS/TSHOWER. THE RAP/HRRR SEEM TO FOCUS OVER THE CENTRAL AND
SOUTHERN PARTS OF THE FORECAST AREA WHILE THE NAM IS FARTHER
NORTH AND IN SOUTHWEST IOWA. LOW CONFIDENCE IN EXACT
LOCATION...BUT WILL MAINTAIN A LOW POP.
TONIGHT...THE OPEN TROUGH OVER THE ROCKIES CLOSES OFF
WITH OMEGA INCREASING TO THE WEST AND TO THE NORTH. WITH THE
DOUBLE FRONT STRUCTURE THERE COULD BE A COUPLE OF AREAS OF
PRECIPITATION. THE PRECIPITATION BECOMES EVEN MORE ORGANIZED
WEDNESDAY INTO WEDNESDAY NIGHT WITH RAIN BECOMING LIKELY. WITH A
CHANCE FOR SHOWERS AND THUNDERSTORMS THURSDAY. WE ARE OUTLOOKED IN
THE EXCESSIVE RAIN AREA FOR DAY THREE (WED/WED NIGHT)...BUT WILL
NEED TO SEE HOW THE STORM SYSTEM EVOLVES UNTIL THEN.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM CDT TUE SEP 22 2015
AT THE BEGINNING OF THE EXTENDED...THE TROPICAL REMNANTS CONTINUE
TO AFFECT THE AREA...MORESO WITH THE EC COMPARED TO THE
NAM/GFS. LINGERED A SLIGHT CHANCE FOR SHOWERS THURSDAY NIGHT WITH
DRY WEATHER FOR MUCH OF THE REST OF THE EXTENDED WITH MID LEVEL
RIDGING. TEMPERATURES SHOULD BE NEAR TO 5 TO 10 DEGREES ABOVE
NORMAL IN THE 70S TO LOWER 80S.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 626 PM CDT MON SEP 21 2015
INFLUX OF LLVL MOISTURE COMBINED WITH DECREASING BNDRY LYR WINDS
WILL ALLOW FOR DETERIORATING CONDITIONS AT ALL TAF SITES EARLY
TUESDAY MORNING. THEREFORE HAVE IFR/LIFR TEMPO GROUPS IN PLACE
AT KOFK AND KOMA. AS FOR KLNK...EXPECT ONLY MVFR CONDITIONS DURING
THIS TIME. VFR THE THEREAFTER.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
948 AM PDT TUE SEP 22 2015
.SYNOPSIS..A WEAKENING LOW PRESSURE SYSTEM MOVING ACROSS FAR
SOUTHERN CALIFORNIA AND ARIZONA WILL PRODUCE EXTENSIVE CLOUD COVER
ALONG WITH SCATTERED SHOWERS AND A FEW THUNDERSTORMS OVER AREAS NEAR
AND SOUTH OF I-15 THROUGH THIS EVENING. DRIER AIR WILL MOVE IN ON
WEDNESDAY...WITH TEMPERATURES RISING ABOVE NORMAL THROUGH THE
WEEKEND.
&&
.UPDATE...THE 12Z LAS SOUNDING AND RECENT SURFACE ANALYSES SHOWED
CONSIDERABLE INSTABILITY AND MOISTURE IN PLACE. HOWEVER...CONVECTION
WILL BE LIMITED BY THE EXTENSIVE CLOUD SHIELD LIMITING SURFACE
HEATING OVER CLARK...SAN BERNARDINO AND MOHAVE COUNTIES. OUR
FORECAST AREA WILL BE ON BACK SIDE OF THE ELONGATED CIRCULATION
EXTENDING FROM FAR SOUTHERN CALIFORNIA UP ACROSS CENTRAL ARIZONA WE
WILL NOT SEE MUCH DYNAMIC SUPPORT FROM THIS FEATURE. IT APPEARS THE
MOUNTAINS OF CLARK COUNTY MAY SEE ENOUGH HEATING THIS AFTERNOON TO
INITIATE A FEW THUNDERSTORMS AND THE LATEST HRRR MODEL DEPICTS THIS
POTENTIAL. ELSEWHERE SOUTH OF I-15 WE SHOULD SEE SOME ISOLATED-
SCATTERE LIGHT SHOWERS AND MAYBE A FEW THUNDERSTORMS OVER EASTERN
MOHAVE COUNTY THIS AFTERNOON. THE POP/WX/QPF GRIDS WERE TRIMMED BACK
TO REFLECT THESE TRENDS.
&&
.AVIATION...FOR MCCARRAN...LIGHT WINDS SHOULD BECOME EAST TO
SOUTHEAST APPROACHING 10 KNOTS DURING THE AFTERNOON HOURS. THERE
WILL BE A CHANCE FOR SHOWERS OR THUNDERSTORMS OVER THE SPRING
MOUNTAINS BY LATE THIS AFTERNOON WHICH COULD LEAD TO ERRATIC
WINDS...BUT CONFIDENCE IS TOO LOO TO MENTION IN THE TAF. CLEARING
CONDITIONS TONIGHT WITH NO SIGNIFICANT WEATHER EXPECTED WEDNESDAY OR
THURSDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY
GENERALLY ALONG AND SOUTH OF INTERSTATE 15. STRONGER STORMS WILL BE
CAPABLE OF PRODUCING ERRATIC WINDS...BRIEF HEAVY RAIN...LOW CEILINGS
AND MOUNTAIN OBSCURATION. DRIER WEATHER IS EXPECTED TO RETURN LATER
TODAY AND CONTINUE THROUGH THE WEEK. &&
.PREV DISCUSSION
232 AM PDT TUE SEP 22 2015
.SHORT TERM...TODAY THROUGH THURSDAY.
MOST OF THE EVENING HOURS WERE UNEVENTFUL UNTIL NEAR MIDNIGHT WHEN
SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS PARTS OF SOUTHERN MOHAVE
COUNTY. RAIN GAUGES IN AND AROUND WIKIEUP HAVE THUS FAR THROUGH 2 AM
HAVE MEASURED .08-.12 INCHES OF RAIN. THIS ACTIVITY IS GENERALLY
MOVING WEST TO SOUTHWEST. SATELLITE IMAGERY SHOWS EXTENSIVE CLOUD
COVER ACROSS THE AREA AS PACIFIC TROUGHING MOVES CLOSER TO THE
SOUTHWEST CONUS. AT THE SURFACE, OBSERVATIONS SHOW 60+ DEGREE
DEWPOINTS HAVE MOVED INTO THE LAS VEGAS VALLEY AND AS FAR NORTH AS
MESQUITE NV. THE FAR NORTHERN AREAS OF THE CWA REMAIN DRY AT THE
SURFACE WITH TEENS AND 20S FOR DEWPOINT TEMPS.
FOR TODAY, THE TROUGH CONTINUES TO WEAKEN AS IT QUICKLY MOVES ACROSS
THE SOUTHWEST DESERTS. THE 00Z GFS HAS THE TROUGH AXIS EAST OF
MOHAVE COUNTY BY LATE THIS AFTERNOON WITH DYNAMIC SUPPORT FROM THE
TROUGH DIMINISHING AS IT HEADS EAST. CURRENT THINKING IS THE BEST
CHANCE FOR SHOWER AND THUNDERSTORM ACTION TODAY WILL BE ALONG AND
SOUTH OF INTERSTATE 15 WITH A FEW STORMS POSSIBLE A BIT FURTHER
NORTH OF THIS LINE WHERE DEEPER MOISTURE AND WEAK INSTABILITY ARE
FORECAST. MODEL MOISTURE/INSTABILITY PROGS AND RELATIVELY WEAK UPPER
LEVEL FLOW SUGGEST LOCALIZED FLASH FLOODING WILL BE POSSIBLE WHERE
STRONGER STORMS DEVELOP. SHOWER ACTIVITY SHOULD RAPIDLY END TONIGHT
WITH DRY CONDITIONS AND WARMER TEMPERATURES EXPECTED WEDNESDAY AND
THURSDAY. THE LATEST MOS GUIDANCE SUGGESTS VEGAS COULD HIT 100
DEGREES AS EARLY AS THURSDAY.
.LONG TERM...FRIDAY THROUGH TUESDAY
USING A BLEND OF THE ECMWF/CMC THIS MORNING AS LAST FEW RUNS OF THE
GFS HAVING A DIFFICULT TIME RESOLVING UPSTREAM SHORTWAVE ENERGY
ACROSS THE NORTHEAST PACIFIC. THE ECMWF/CMC BOTH ARE NOW
SLOWER/LAGGING AN UPPER TROUGH OFF SHORE OF THE PAC NW COAST WELL
INTO EARLY NEXT WEEK. FOR US, DOWNSTREAM OF THE TROUGH THAT MEANS A
STRONG RIDGE WILL BE IN PLACE OVER THE INTERMOUNTAIN WEST. BUMPED UP
HIGHS SOME MORE AS GUIDANCE CONTINUES TO GET WARMER. NOW WE ARE
LOOKING AT HIGH RUNNING SOME 7 TO 11 DEGREES ABOVE NORMAL THIS
WEEKEND. &&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
HOWEVER SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
ACCORDING TO STANDARD OPERATING PROCEDURES. &&
$$
UPDATE...ADAIR
PREV DISCUSSION...SALMEN/PIERCE
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
513 AM PDT TUE SEP 22 2015
.SYNOPSIS...AN UPPER LEVEL TROUGH OFF THE SOUTHERN CALIFORNIA COAST
WILL WEAKEN AND MOVE INLAND OVER NORTHERN BAJA THIS MORNING BRINGING
A CHANCE OF THUNDERSTORMS TO AREAS ALONG AND SOUTHEAST OF A LINE
FROM BARSTOW TO CALIENTE. DRIER AIR WILL MOVE IN ON WEDNESDAY...WITH
TEMPERATURES RISING ABOVE NORMAL THROUGH THE WEEKEND.
&&
.UPDATE...PERSISTENT LINE OF SHOWERS/EMBEDDED ISOLATED THUNDERSTORMS
OVER SOUTHEAST MOHAVE COUNTY HAS MADE LITTLE PROGRESS WESTWARD AND
IN FACT LOOKS TOO BE DISSIPATING. LATEST HRRR AND 06Z MODEL OUTPUT
SHOWS THE I-15 CORRIDOR BETWEEN PRIMM AND MESQUITE STAYING DRY
THROUGH LATE MORNING SO TRIMMED BACK ON POPS. MAY SEE SOMETHING
DEVELOP CLOSER TO LAUGHLIN/SEARCHLIGHT LATER BUT CONFIDENCE EVEN
THERE IS LOW. &&
.PREV DISCUSSION
232 AM PDT TUE SEP 22 2015
.SHORT TERM...TODAY THROUGH THURSDAY.
MOST OF THE EVENING HOURS WERE UNEVENTFUL UNTIL NEAR MIDNIGHT WHEN
SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS PARTS OF SOUTHERN MOHAVE
COUNTY. RAIN GAUGES IN AND AROUND WIKIEUP HAVE THUS FAR THROUGH 2 AM
HAVE MEASURED .08-.12 INCHES OF RAIN. THIS ACTIVITY IS GENERALLY
MOVING WEST TO SOUTHWEST. SATELLITE IMAGERY SHOWS EXTENSIVE CLOUD
COVER ACROSS THE AREA AS PACIFIC TROUGHING MOVES CLOSER TO THE
SOUTHWEST CONUS. AT THE SURFACE, OBSERVATIONS SHOW 60+ DEGREE
DEWPOINTS HAVE MOVED INTO THE LAS VEGAS VALLEY AND AS FAR NORTH AS
MESQUITE NV. THE FAR NORTHERN AREAS OF THE CWA REMAIN DRY AT THE
SURFACE WITH TEENS AND 20S FOR DEWPOINT TEMPS.
FOR TODAY, THE TROUGH CONTINUES TO WEAKEN AS IT QUICKLY MOVES ACROSS
THE SOUTHWEST DESERTS. THE 00Z GFS HAS THE TROUGH AXIS EAST OF
MOHAVE COUNTY BY LATE THIS AFTERNOON WITH DYNAMIC SUPPORT FROM THE
TROUGH DIMINISHING AS IT HEADS EAST. CURRENT THINKING IS THE BEST
CHANCE FOR SHOWER AND THUNDERSTORM ACTION TODAY WILL BE ALONG AND
SOUTH OF INTERSTATE 15 WITH A FEW STORMS POSSIBLE A BIT FURTHER
NORTH OF THIS LINE WHERE DEEPER MOISTURE AND WEAK INSTABILITY ARE
FORECAST. MODEL MOISTURE/INSTABILITY PROGS AND RELATIVELY WEAK UPPER
LEVEL FLOW SUGGEST LOCALIZED FLASH FLOODING WILL BE POSSIBLE WHERE
STRONGER STORMS DEVELOP. SHOWER ACTIVITY SHOULD RAPIDLY END TONIGHT
WITH DRY CONDITIONS AND WARMER TEMPERATURES EXPECTED WEDNESDAY AND
THURSDAY. THE LATEST MOS GUIDANCE SUGGESTS VEGAS COULD HIT 100
DEGREES AS EARLY AS THURSDAY.
.LONG TERM...FRIDAY THROUGH TUESDAY
USING A BLEND OF THE ECMWF/CMC THIS MORNING AS LAST FEW RUNS OF THE
GFS HAVING A DIFFICULT TIME RESOLVING UPSTREAM SHORTWAVE ENERGY
ACROSS THE NORTHEAST PACIFIC. THE ECMWF/CMC BOTH ARE NOW
SLOWER/LAGGING AN UPPER TROUGH OFF SHORE OF THE PAC NW COAST WELL
INTO EARLY NEXT WEEK. FOR US, DOWNSTREAM OF THE TROUGH THAT MEANS A
STRONG RIDGE WILL BE IN PLACE OVER THE INTERMOUNTAIN WEST. BUMPED UP
HIGHS SOME MORE AS GUIDANCE CONTINUES TO GET WARMER. NOW WE ARE
LOOKING AT HIGH RUNNING SOME 7 TO 11 DEGREES ABOVE NORMAL THIS
WEEKEND. &&
.AVIATION...FOR MCCARRAN...WINDS GENERALLY WEST TO SOUTHWEST UNDER
8KTS THROUGH THE MORNING HOURS THEN SOUTHEAST AROUND 10KTS WITH
HIGHER GUSTS THIS AFTERNOON. A SHIFT TO THE SOUTH OR SOUTHWEST IS
POSSIBLE BY LATER IN THE AFTERNOON. THE WILL BE A CHANCE FOR RAIN
SHOWERS OR A THUNDERSTORM THIS AFTERNOON WITH SOME POTENTIAL FOR
LOWER CIGS AT OR NEAR THE TERMINAL. CLEARING CONDITIONS TONIGHT WITH
NO SIGNIFICANT WEATHER EXPECTED WEDNESDAY OR THURSDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY
GENERALLY ALONG AND SOUTH OF INTERSTATE 15. STRONGER STORMS WILL BE
CAPABLE OF PRODUCING ERRATIC WINDS...BRIEF HEAVY RAIN...LOW CEILINGS
AND MOUNTAIN OBSCURATION. DRIER WEATHER IS EXPECTED TO RETURN
LATER TODAY AND CONTINUE THROUGH THE WEEK.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
HOWEVER SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
SALMEN/PIERCE
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1043 PM EDT WED SEP 23 2015
.SYNOPSIS...
BROAD HIGH PRESSURE WILL EXTEND OVER THE AREA FROM THE NORTH
THROUGH THE WEEKEND. LOW PRESSURE OFFSHORE TO THE SOUTHEAST
WILL MOVE SOUTHWEST THROUGH THURSDAY...AND THEN WEST FRIDAY.
LOW PRESSURE WILL MOVE NORTHEAST OVER THE AREA THIS WEEKEND AND
AWAY FROM THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...NO SIG CHANGE TO THE UPDATE. HAVE NOTED
A BIT MORE DRIZZLE THAN RAIN SHOWERS THIS EVENING AS MOISTURE
CONTINUES TO STREAM INTO THE IMMEDIATE COAST. SO HAVE ADJUSTED WX
TO REFLECT THIS. APART FROM THIS COSMETIC ISSUE...THE FORECAST IS
ON TRACK FOR A BREEZY...CLOUDY AND DRIZZLY NIGHT ALONG OUR COAST.
PREVIOUS DISCUSSION...NO REAL CHANGE TO THE WEATHER PATTERN THAT
HAS GRIPPED THE REGION THIS WEEK. HIGH PRESSURE RIDGING SOUTH INTO
THE CAROLINAS IS PRODUCING A DAMMING/WEDGE SURFACE PATTERN WHILE A
WEAK/BROAD AREA OF LOW PRESSURE OFFSHORE IS SLOWLY RETROGRESSING
TOWARD THE SOUTHEAST COAST. AS BEEN THE THE CASE THE PAST SEVERAL
DAYS THE MOST DIFFICULT PORTION OF THE FORECAST CONCERNS
DETERMINING THE LOCATION, TIMING, AND AMOUNTS OF PRECIPITATION.
THE MODELS HAVE BEEN TOO AGGRESSIVE THE PAST 3 DAYS IN FORECASTING
PRECIPITATION ACROSS EASTERN NC. THUS WILL DECREASE POPS FOR THE
EVENING HOURS TO 20-30% AS RADAR INDICATES WHAT LITTLE
PRECIPITATION THERE IS WAS LOCATED MAINLY OFFSHORE. WILL MAINTAIN
CURRENT 30-50% POPS AFTER MIDNIGHT AND CONTINUE TO MONITOR
PRECIPITATION TRENDS BUT THESE MAY BE OVERDONE AND MAY NEED TO BE
DECREASED WITH THE 10 PM UPDATE. L0W TEMPERATURES OVERNIGHT WILL
RANGE FROM THE MID 60S FAR WEST TO LOWER 70S COAST WITH OVERCAST
SKIES AND GUSTY NORTHEAST WINDS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
AS OF 315 PM WEDNESDAY...GOOD AGREEMENT AMONGST THE GFS/NAM12 AND
ECMWF REGARDING HIGH LIKELIHOOD OF PRECIPITATION TOMORROW AS
SURFACE LOW AS SURFACE LOW MOVES WEST AND MID/UPPER LEVEL LOW
SLOWLY PULLS NORTHEAST FROM THE CENTRAL GULF COAST. GOOD MOISTURE
FLUX AND ISENTROPIC LIFT SHOULD LEAD TO WIDESPREAD LIGHT TO
MODERATE RAIN ACROSS THE REGION...PRIMARILY IN THE AFTERNOON HOURS
THURSDAY. CLOUD COVER AND PRECIPITATION WILL HOLD MAXIMUM
TEMPERATURES GENERALLY IN THE MID/UPPER 70S. RAINFALL AMOUNTS
SHOULD AVERAGE ONE QUARTER TO ONE HALF INCH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM WED...A COMPLEX FORECAST CONTINUES ACROSS EASTERN NC
BRINGING WET AND BREEZY TO WINDY CONDITIONS THROUGH MUCH OF THE
WEEKEND.
THURSDAY NIGHT...MDLS SHOW OFFSHORE CSTL TRF BECOMING LESS
DEFINED AND SHIFTING TOWARD THE COAST. PLENTY OF MOISTURE WILL
CONT TO STREAM ACRS THE REGION WITH PRECIP WTR VALUES NEAR 2
INCHES. WILL HAVE LIKELY POPS ALL AREAS AS MDLS SHOW GOOD QPF OVER
THE REGION WITH INCREASED UPPER LEVEL DIFFLUENCE. CLOUDS AND
PRECIP WILL KEEP TEMPS MILD WITH LOWS IN THE MID TO UPPER 60S
INLAND AND LOWER 70S BEACHES.
FRIDAY THROUGH SUNDAY...NUMEROUS SHOWER...SOME HEAVY EXPECTED INTO
SUNDAY AS DEEP MOISTURE PERSISTS OVER THE REGION WITH SFC TRF IN
THE AREA AND WEAK DIFL ALOFT. CONT LIKELY POPS THRU SAT NIGHT AND
SEVERAL INCHES OF RAINFALL WILL BE POSS IN SPOTS ESPCLY COAST.
SOME DIFF IN MDLS CONT LATER IN WEEKEND WITH GFS QUICKER TO LIFT
SFC LOW AND DEEPER MOISTURE N OF THE REGION SUNDAY. FOR NOW CONT
PREV FCST WITH CHC POPS SUNDAY GIVEN UNCERTAINTY. WIDESPREAD
CLOUDS AND PRECIP WILL KEEP TEMPS STEADY THRU SUNDAY WITH MILD
LOWS IN 60S TO LOWER 70S WITH HIGHS MOSTLY IN THE 75 TO 80 DGR
RANGE.
MONDAY THRU WED...LOW PRES PROGGED TO MOVE NE OF THE AREA EARLY
NEXT WEEK WITH A DRYING TREND AS THE DEEP MOISTURE LIFTS NORTH OF
THE AREA AND HIGH PRES BUILDS IN FROM THE WEST. TEMPS WARM
SLIGHTLY WITH GREATER INSOLATION EXPECTED AND EXPECT HIGHS IN THE
LOWER 80S.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 00Z THURSDAY/...
AS OF 630 PM WEDNESDAY...EXPECTING VARIABILITY AT THE INLAND
(ISO/PGV) TAF SITES THIS EVENING FROM MVFR TO VFR CEILINGS WHILE
MVFR CEILINGS PERSIST AT OAJ AND EWN. LATER TONIGHT THE MODELS
INDICATE THAT THE LOW LEVEL FLOW WILL VEER FROM NORTHEAST TO EAST
AND MOISTEN THE LOW LEVELS. MOIST OF THE NUMERICAL AVIATION
GUIDANCE IS INDICATING IFR CEILINGS DEVELOPING LATE TONIGHT (AFTER
06Z) WHILE THE NARRE AND HRRR GUIDANCE ARE AT ODDS WITH THIS. DUE
TO THIS UNCERTAINTY WILL MAINTAIN A MVFR CEILING FORECAST AND
CONTINUE TO MONITOR. ON THURSDAY WE ARE EXPECTING MORE WIDESPREAD
SHOWER ACTIVITY AND EXPECT A CONTINUATION OF MVFR CEILINGS.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM WED...POOR FLYING THRU MUCH OF THE WEEKEND. DEEP
MOISTURE OVER THE AREA WITH LEAD TO BOUTS OF SHRA WITH PROLONGED
PDS PERIODS OF SUB VFR CONDITIONS LIKELY...WITH SOME IFR
EXPECTED. MOISTURE BEGINS TO DIMINISH LATER SUN AND ESPCLY MON
WITH LESS SHRA AND PROB MORE VFR.
&&
.MARINE...
SHORT TERM /THROUGH THU/...
AS OF 1030 PM WEDNESDAY...NO SIG CHANGES TO THE UPDATE WITH STRONG
NE FLOW CONTINUING ACROSS THE WATERS. WINDS 20-25KTS GUSTING
AROUND 30KTS. SEAS 6-11 FT.
PREVIOUS DISCUSSION...GUSTY N/NE WINDS AND ROUGH SEAS WILL
PERSIST THROUGH THURSDAY WITH LOW PRESSURE OFFSHORE AND STRONG
HIGH PRESSURE LOCKED OVER THE NORTHEAST. THE LOW SHOULD SLOWLY
START TO DRIFT TOWARD THE SOUTHEAST COAST LATE TONIGHT DECREASING
THE GRADIENT AND WINDS SHOULD DIMINISH A BIT INTO THURSDAY...BUT
PER LOCAL SWAN/NWPS...SEAS SHOULD REMAIN ELEVATED.
CURRENTLY...WINDS ARE GUSTING TO AROUND 30 KNOTS WITH SEAS 6 TO 10
FEET. AS WITH THE WINDS...SEAS WILL SUSBIDE A BIT ON THURSDAY BUT
SHOULD STILL REMAIN IN THE 6 TO 8 FOOT RANGE AT MOST LOCATIONS.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM WED...HIGH CONFIDENCE IN POOR BOATING CONDITIONS FOR
MUCH OF THE LONG TERM AS PERSISTENT MODERATE TO OCNLY STRONG NE/E
WINDS AND ROUGH SEAS WILL DOMINATE. THE TWO MAIN FEATURES ARE
PERSISTENT HIGH PRESSURE THAT WILL BE ANCHORED TO THE NORTH AND AN
ELONGATED AREA OF LOW PRESSURE OFF THE SE COAST THAT WILL PRODUCE
A TIGHT PRESSURE GRADIENT. THE LOW WILL MOVE ONSHORE TO THE SOUTH
OF ENC ON THURSDAY INTO FRIDAY, WITH WINDS 15-25KT WITH SEAS 4-8
FT HIGHEST NORTH.
MODELS ARE STILL NOT IN THE BEST AGREEMENT WITH THE NEXT SYSTEM
THIS WEEKEND. GFS QUICKLY LIFTS LOW OVER AND N OF REGION SUNDAY
WHILE ECMWF KEEPS IT TO THE S THRU SUNDAY WHICH LEADS TO LONGER
PERIOD OF STRONGER ONSHORE WINDS. CONT PREV FCST WITH MODERATE
ONSHORE FLOW CONT INTO SUNDAY. SEAS EXPECTED TO BUILD TO 8 TO 11
FT CNTRL AND N AND 4 TO 6 FEET S THRU THE WEEKEND.
MDLS DIFFER A BIT WITH WIND DIR EARLY NEXT WEEK BUT AGREE ON
DIMINISHING WINDS...MAINLY FROM A NRLY DIR. AS WINDS DIMINISH
SEAS WILL SUBSIDE TO 4 TO 6 FT N AND 3 TO 5 FT S LATER MON.
&&
.TIDES/COASTAL FLOODING...
AS OF 325 PM WEDNESDAY...THE HIGH SURF ADVISORY HAS BEEN EXTENDED
THROUGH THURSDAY AFTERNOON. PERSISTENT NORTHEAST WINDS WILL
CONTINUE TO PRODUCE 6 TO 9 FOOT SURF ALONG WITH A HIGH THREAT OF
RIP CURRENTS AND POSSIBLE BEACH EROSION.
UNCERTAINTY CONTINUES THIS WEEKEND...BUT ROUGH SEAS AND STRONG NE
WINDS ARE POSSIBLE...ESPECIALLY SATURDAY. IN ADDITION TO THE
OCEANSIDE IMPACTS, SOUNDSIDE LOCATIONS VULNERABLE TO STRONG NE
WINDS COULD SEE MINOR WATER LEVEL RISES, WHICH WOULD BE
EXACERBATED BY THE HIGH ASTRONOMICAL TIDES THIS WEEKEND INTO EARLY
NEXT WEEK. STAY TUNED TO LATER FORECASTS AS HOPEFULLY CONFIDENCE
INCREASES.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 6 PM EDT THURSDAY FOR NCZ103.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT THURSDAY FOR AMZ130-131-
135.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR AMZ150-152-154.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR AMZ156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...JME/CTC/LEP
SHORT TERM...CTC
LONG TERM...RF
AVIATION...RF/JME
MARINE...RF/JME/CTC/LEP
TIDES/COASTAL FLOODING...CTC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
957 PM CDT WED SEP 23 2015
.UPDATE...
ISSUED AT 948 PM CDT WED SEP 23 2015
MAIN UPDATE WAS TO ADJUST POPS FOR ONGOING CONVECTION OVER THE
NORTH CENTRAL...AND ANTICIPATED RE-DEVELOPMENT OF SHOWERS AND
ISOLATED THUNDERSTORMS ACROSS THE NORTH LATER TONIGHT. SOME
INDICATIONS OF THE SHOWERS CAN ALREADY BE SEEN OVER NORTHWEST
NORTH DAKOTA LATE THIS EVENING. LATEST TIME LAGGED HRRR BRINGS
ANOTHER ROUND OF SHOWERS AND POSSIBLE THUNDER INTO THE TURTLE
MOUNTAINS AREA AFTER MIDNIGHT FROM AROUND 7 TO 10 UTC. MAY NEED TO
EXTEND CURRENT AREAL FLOOD ADVISORY IF THIS PANS OUT...WITH
DOPPLER ESTIMATES OF UP TO 4 INCHES ACROSS ROLETTE COUNTY. ONLY
GROUND TRUTH RECEIVED SO FAR WERE 1 INCH SOUTH OF BELCOURT AND
1.58 INCHES IN BOTTINEAU. BOTH OF THESE WERE AWAY FROM THE HIGHEST
ESTIMATES.
ALSO ADDED PATCHY FOG ACROSS WESTERN AND CENTRAL NORTH DAKOTA. FOG
ALREADY SETTLING IN AT KJMS. SKIES REMAIN CLEAR IN THE SOUTHWEST
AND WITH MOISTURE TRANSPORT CONTINUING INTO THE AREA...EXPECT LOW
STRATUS AND/OR FOG WILL BE A GOOD BET HERE AS WELL. MOST ANY
LOCATION COULD SEE FOG LATE TONIGHT INTO THURSDAY MORNING.
UPDATE ISSUED AT 645 PM CDT WED SEP 23 2015
HAVE RAISED POPS ACROSS THE FAR NORTH CENTRAL THIS EVENING WITH
SHOWERS AND THUNDERSTORMS TRACKING EAST NORTHEAST FROM AROUND
SHERWOOD TO BOTTINEAU AND ROLLA. THIS ACTIVITY SHOULD MOVE OUT OF
THE AREA IN THE NEXT FEW HOURS. LATEST MESO-SCALE MODELS SHOW
ANOTHER AREA OF SHOWERS DEVELOPING LATER THIS EVENING OVER THE
WEST CENTRAL AND TRACKING MAINLY ACROSS THE NORTHERN HALF OF THE
CWA. WILL CONTINUE TO MONITOR BUT CURRENT POPS DO NOT REFLECT
THIS. WE DO HAVE SOME SLIGHT CHANCE TO CHANCE POPS REMAINING
ACROSS THE NORTH TONIGHT SO THINK THIS WILL SUFFICE UNLESS WE SEE
SHOWERS DEVELOPING AGAIN LATER THIS EVENING.
ADJUSTED SKY COVER AS WE HAVE CLEARED OUT OVER A GOOD PORTION OF
THE SOUTHWEST. MAIN QUESTION HERE IS WILL WE CLOUD BACK UP LATER
TONIGHT WITH LOW STRATUS. WITH LOW LEVEL MOISTURE REMAINING...HAVE
LEANED THIS WAY WITH THE 00Z TAF ISSUANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 258 PM CDT WED SEP 23 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER EASTERN COLORADO INTO
WESTERN NEBRASKA WITH HIGH OVER NORTHERN/CENTRAL MANITOBA INTO
ONTARIO. UPPER LEVEL ANALYSIS PLACES BROAD LOW OFF THE BC COAST
WITH SPLIT FLOW OVER OUR REGION AS COMPACT LOW LIFTS LIFTS FROM
NORTHERN NEBRASKA INTO SOUTHERN SOUTH DAKOTA. THIS IS RESULTING IN
A FEW LIGHT SHOWERS OVER FAR SOUTHEAST NORTH DAKOTA...WHILE A FEW
SHOWERS CONTINUE OVER NORTHERN NORTH DAKOTA AS A SHORT WAVE MOVES
THROUGH THE NORTHERN STREAM.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...UPPER LOW STARTS TO
OPEN UP AND PROGRESS EASTERLY. A FEW LIGHT SHOWERS MAY WRAP INTO
THE AREA FROM THIS THROUGH THE EARLY EVENING...THOUGH THE BULK OF
THE PRECIPITATION WILL REMAIN WELL TO THE SOUTHEAST OF THE AREA.
IN THE MEANTIME...A SERIES OF SHORT WAVES WILL CONTINUE TO MOVE
THROUGH THE NORTHERN STREAM OVER NORTHERN NORTH DAKOTA. THIS WILL
KEEP CHANCES FOR SHOWERS GOING THROUGH THE EVENING OVER THE NORTH
BEFORE TAPERING TOWARDS EARLY MORNING. AMPLE LOW LEVEL MOISTURE
REMAINS IN PLACE WHICH WILL KEEP LOW CLOUD COVER OVER THE AREA.
SOME MODELS SUGGEST THE POSSIBILITY FOR SOME FOG...BUT WILL HOLD
OUT FOR NOW GIVEN THE EXPECTED CONTINUED LOW CLOUD COVER. WITH
THAT SAID...WILL HAVE LATER SHIFTS TAKE A LOOK AT THIS AND IF
THERE IS SOME CLEARING FOG WILL BECOME A CONCERN.
ON THURSDAY...RIDGING DEVELOPS OVER THE AREA WITH SKIES GRADUALLY
CLEARING FROM WEST TO EAST. TEMPERATURES WILL REBOUND TO ABOVE
AVERAGE OVER MOST LOCATIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 23 2015
DETERMINISTIC MODELS AND ENSEMBLE OUTPUT SUPPORT BROAD UPPER RIDGE
OVER NORTH AMERICA EVENTUALLY BREAKING DOWN BY LATE WEEKEND AS
TROUGH MOVES INTO CENTRAL CANADA. THIS PATTERN WILL SUPPORT WELL
ABOVE NORMAL TEMPERATURES...WITH HIGHS IN THE 80S BY SATURDAY BEFORE
DROPPING BACK TO 60S AND 70S SUNDAY AND MONDAY. SOMEWHAT GREATER
UNCERTAINTY EARLY NEXT WEEK AS MODEL SOLUTIONS BEGIN TO
DIVERGE...BUT LOW POPS CONTINUE TO BE WARRANTED SUN/MONDAY AS UPPER
RIDGE BREAKS DOWN. INSTABILITY IS ALSO LACKING...WITH THE GFS ONLY
INDICATING WEAK INSTABILITY ON MONDAY...SO ANY PRECIP WOULD BE
EXPECTED TO BE PREDOMINATELY SHOWERS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 948 PM CDT WED SEP 23 2015
MVFR TO LOW VFR CLOUDS REMAIN FROM WILLISTON TO MINOT AND
JAMESTOWN WITH MOSTLY CLEAR SKIES AT KDIK AND KBIS. A LIGHT EAST
TO SOUTHEAST FLOW REMAINS OVERNIGHT AND MESO-SCALE MODELS INDICATE
STRATUS DEVELOPING AGAIN LATE TONIGHT INTO THURSDAY MORNING
ACROSS MOST OF THE FORECAST AREA. HAVE THUS BROUGHT IN IFR-LIFR
CEILINGS LATE TONIGHT AT TAF SITES...WITH CEILINGS LIFTING DURING
THE MORNING TO VFR CONDITIONS IN THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JJS
LONG TERM...JNS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1232 PM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 1222 PM CDT TUE SEP 22 2015
LIGHT SHOWERS CONTINUE OVER NORTHERN PORTIONS OF THE AREA IN LINE
WITH RIGHT ENTRANCE REGION OF PASSING JET STREAK. HAVE ADJUSTED
PRECIPITATION CHANCES IN LINE WITH CURRENT OBSERVATIONS...LIFTING
THE PRECIPITATION TO THE NORTHEAST AS JET STREAK MOVES OUT OF THE
AREA LATER THIS AFTERNOON. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 633 AM CDT TUE SEP 22 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS VERY LIGHT
SHOWER ACTIVITY CONTINUES ACROSS THE NORTHWEST INTO THE I-94
CORRIDOR CENTRAL. GIVEN DRY LOW LEVEL AIR IN PLACE...MUCH OF THE
PRECIPITATION IS LIKELY NOT REACHING THE GROUND. ONGOING FORECAST
BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE
08-10 UTC HRRR ITERATIONS WHICH CAPTURES RADAR TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 218 AM CDT TUE SEP 22 2015
FORECAST HIGHLIGHTS ARE ISOLATED TO SCATTERED SHOWERS WEST THROUGH
PORTIONS OF CENTRAL NORTH DAKOTA TUESDAY MORNING...LIFTING NORTH
THROUGH TUESDAY AFTERNOON...AND MOISTURE SURGING INTO THE JAMES
RIVER VALLEY TUESDAY NIGHT RESULTING IN INCREASING CHANCES FOR
SHOWERS AND THUNDERSTORMS.
LATEST SUITE OF SATELLITE IMAGERY/SURFACE OBSERVATIONS AND
LOCAL/REGIONAL RADAR SHOW A BAND OF ISOLATED TO SCATTERED RAIN
SHOWERS STRETCHED WEST TO EAST...FROM CENTRAL MONTANA INTO
WESTERN NORTH DAKOTA. CLOUD TOPS CONTINUE TO COOL WITH
CORRESPONDING HIGHER REFLECTIVITY AS VERTICAL MOTION/LARGE SCALE
ASCENT BEING ATTRIBUTED TO A DEPARTING 110KT JET MAX IN SOUTHERN
MANITOBA WITHE THE RIGHT ENTRANCE REGION OVER NORTHEAST MONTANA...
ISENTROPIC ASCENT PER 300K/305K PRESSURE SURFACE...AND MID LEVEL
FRONTOGENESIS. LIGHT RAIN WAS BEING REPORTED AT BEACH WITH CLOUD
BASES REPORTED AT 6KFT AND 9KFT. MODELS AGREE WITH THIS BAND
LIFTING NORTH DURING THE DAY BUT AGREEMENT ON THE PLACEMENT/AREAL
COVERAGE OF PRECIPITATION SEEMED TO BE LACKING. STARTED WITH THE
CURRENT RADAR FOR POP TRENDS...AND THEN UTILIZED A MODEL BLEND OF
THE HRRR/RAP13/NAM/GFS/ECMWF/PREVIOUS FORECAST FOR THE REMAINDER
OF THE DAY. MUCH COOLER TEMPERATURES TODAY WITH EASTERLY WINDS
BETWEEN 10 AND 25 MPH...AS HIGHS TOP OUT IN THE 60S.
WATER VAPOR SHOWS OUR NEXT UPSTREAM SHORTWAVE NOW LOCATED OVER
NORTHWESTERN NEW MEXICO. AS THIS SHORTWAVE APPROACHES TUESDAY
EVENING/NIGHT...SURFACE LOW PRESSURE OVER NORTHERN NEBRASKA WITH
AN ATTENDING WARM FRONT WILL REACH INTO SOUTHEAST NORTH DAKOTA
DAKOTA. INCREASING LOW LEVEL SOUTHEAST TO SOUTHERLY WINDS AND
MOISTURE ADVECTION WILL RESULT IN CHANCES FOR SHOWERS AND THUNDERSTORMS
MAINLY AFTER 06Z WEDNESDAY. THE GREATEST CHANCE FOR PRECIPITATION WILL
BE IN THE JAMES RIVER VALLEY THEN TAPERING OFF QUICKLY AS YOU HEAD
WEST INTO SOUTH CENTRAL NORTH DAKOTA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 218 AM CDT TUE SEP 22 2015
CONTINUED ABOVE NORMAL TEMPERATURES HIGHLIGHT THE EXTENDED
FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON A RELATIVELY COOL...BUT STILL SEASONABLE...WEDNESDAY WITH
HIGHS IN THE 60S AND 70S NORTHWEST OF THE SIGNIFICANT STORM SYSTEM
FORECAST TO IMPACT THE UPPER MISSISSIPPI VALLEY. AS OF NOW...THE
MAIN IMPACT OF HEAVY RAIN WITH THIS STORM IS EXPECTED TO REMAIN
ACROSS EASTERN SOUTH DAKOTA INTO MINNESOTA. HOWEVER...THIS WILL
HAVE TO BE MONITORED SHOULD THE FORECAST TRACK SHIFT SLIGHTLY WEST.
THEREAFTER...AN UPPER LEVEL RIDGE IS FORECAST TO BUILD INTO THE
NORTHERN PLAINS THURSDAY INTO FRIDAY...WITH SOUTHWEST FLOW ALOFT
FOR THE REMAINDER OF THE PERIOD SATURDAY ONWARD. AS A RESULT...A
WARM UP BACK INTO THE 80S IS FORECAST FOR FRIDAY AND SATURDAY.
GIVEN SOUTHWEST FLOW ALOFT SATURDAY INTO EARLY NEXT WEEK...NEAR
DAILY CHANCES FOR ISOLATED SHOWERS AND THUNDERSTORMS RETURN TO THE
FORECAST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1222 PM CDT TUE SEP 22 2015
MAINLY VFR CONDITIONS THIS AFTERNOON INTO EARLY THIS EVENING WITH
SOME SHOWERS PASSING OVER NORTHERN LOCATIONS. CIGS WILL
DETERIORATE OVER THE AREA EARLY WEDNESDAY MORNING TO MVFR
LEVELS...AND WILL REMAIN LOWERED THROUGH MID-DAY. SHRA MAY ALSO
REDUCE VISIBILITIES TO MVFR LEVELS WEDNESDAY MORNING OVER PORTIONS
OF CENTRAL AND EASTERN NORTH DAKOTA.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
ISSUED BY NATIONAL WEATHER SERVICE GRAND FORKS ND
925 AM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 925 AM CDT TUE SEP 22 2015
THE FORECAST REMAINS LARGELY UNCHANGED THIS MORNING. HAVE
MAINTAINED SLIGHT/CHANCE POPS THIS MORNING ACROSS THE NORTHERN
PART OF THE AREA ASSOCIATED WITH MID-LEVEL FRONTOGENESIS LIFTING
NORTHEASTWARD. SFC OBS INDICATE MID-LEVEL CEILINGS WITHIN THE
RADAR RETURNS...SO EXPECT ANY PRECIP REACHING THE GROUND TO BE
QUITE LIGHT. OTHERWISE...ONLY MINOR TWEAKS TO THE FORECAST THIS
MORNING BASED ON CURRENT OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 633 AM CDT TUE SEP 22 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS VERY LIGHT
SHOWER ACTIVITY CONTINUES ACROSS THE NORTHWEST INTO THE I-94
CORRIDOR CENTRAL. GIVEN DRY LOW LEVEL AIR IN PLACE...MUCH OF THE
PRECIPITATION IS LIKELY NOT REACHING THE GROUND. ONGOING FORECAST
BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE
08-10 UTC HRRR ITERATIONS WHICH CAPTURES WELLL RADAR TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 218 AM CDT TUE SEP 22 2015
FORECAST HIGHLIGHTS ARE ISOLATED TO SCATTERED SHOWERS WEST THROUGH
PORTIONS OF CENTRAL NORTH DAKOTA TUESDAY MORNING...LIFTING NORTH
THROUGH TUESDAY AFTERNOON...AND MOISTURE SURGING INTO THE JAMES
RIVER VALLEY TUESDAY NIGHT RESULTING IN INCREASING CHANCES FOR
SHOWERS AND THUNDERSTORMS.
LATEST SUITE OF SATELLITE IMAGERY/SURFACE OBSERVATIONS AND
LOCAL/REGIONAL RADAR SHOW A BAND OF ISOLATED TO SCATTERED RAIN
SHOWERS STRETCHED WEST TO EAST...FROM CENTRAL MONTANA INTO
WESTERN NORTH DAKOTA. CLOUD TOPS CONTINUE TO COOL WITH
CORRESPONDING HIGHER REFLECTIVITY AS VERTICAL MOTION/LARGE SCALE
ASCENT BEING ATTRIBUTED TO A DEPARTING 110KT JET MAX IN SOUTHERN
MANITOBA WITHE THE RIGHT ENTRANCE REGION OVER NORTHEAST MONTANA...
ISENTROPIC ASCENT PER 300K/305K PRESSURE SURFACE...AND MID LEVEL
FRONTOGENESIS. LIGHT RAIN WAS BEING REPORTED AT BEACH WITH CLOUD
BASES REPORTED AT 6KFT AND 9KFT. MODELS AGREE WITH THIS BAND
LIFTING NORTH DURING THE DAY BUT AGREEMENT ON THE PLACEMENT/AREAL
COVERAGE OF PRECIPITATION SEEMED TO BE LACKING. STARTED WITH THE
CURRENT RADAR FOR POP TRENDS...AND THEN UTILIZED A MODEL BLEND OF
THE HRRR/RAP13/NAM/GFS/ECMWF/PREVIOUS FORECAST FOR THE REMAINDER
OF THE DAY. MUCH COOLER TEMPERATURES TODAY WITH EASTERLY WINDS
BETWEEN 10 AND 25 MPH...AS HIGHS TOP OUT IN THE 60S.
WATER VAPOR SHOWS OUR NEXT UPSTREAM SHORTWAVE NOW LOCATED OVER
NORTHWESTERN NEW MEXICO. AS THIS SHORTWAVE APPROACHES TUESDAY
EVENING/NIGHT...SURFACE LOW PRESSURE OVER NORTHERN NEBRASKA WITH
AN ATTENDING WARM FRONT WILL REACH INTO SOUTHEAST NORTH DAKOTA
DAKOTA. INCREASING LOW LEVEL SOUTHEAST TO SOUTHERLY WINDS AND
MOISTURE ADVECTION WILL RESULT IN CHANCES FOR SHOWERS AND THUNDERSTORMS
MAINLY AFTER 06Z WEDNESDAY. THE GREATEST CHANCE FOR PRECIPITATION WILL
BE IN THE JAMES RIVER VALLEY THEN TAPERING OFF QUICKLY AS YOU HEAD
WEST INTO SOUTH CENTRAL NORTH DAKOTA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 218 AM CDT TUE SEP 22 2015
CONTINUED ABOVE NORMAL TEMPERATURES HIGHLIGHT THE EXTENDED
FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON A RELATIVELY COOL...BUT STILL SEASONABLE...WEDNESDAY WITH
HIGHS IN THE 60S AND 70S NORTHWEST OF THE SIGNIFICANT STORM SYSTEM
FORECAST TO IMPACT THE UPPER MISSISSIPPI VALLEY. AS OF NOW...THE
MAIN IMPACT OF HEAVY RAIN WITH THIS STORM IS EXPECTED TO REMAIN
ACROSS EASTERN SOUTH DAKOTA INTO MINNESOTA. HOWEVER...THIS WILL
HAVE TO BE MONITORED SHOULD THE FORECAST TRACK SHIFT SLIGHTLY WEST.
THEREAFTER...AN UPPER LEVEL RIDGE IS FORECAST TO BUILD INTO THE
NORTHERN PLAINS THURSDAY INTO FRIDAY...WITH SOUTHWEST FLOW ALOFT
FOR THE REMAINDER OF THE PERIOD SATURDAY ONWARD. AS A RESULT...A
WARM UP BACK INTO THE 80S IS FORECAST FOR FRIDAY AND SATURDAY.
GIVEN SOUTHWEST FLOW ALOFT SATURDAY INTO EARLY NEXT WEEK...NEAR
DAILY CHANCES FOR ISOLATED SHOWERS AND THUNDERSTORMS RETURN TO THE
FORECAST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 633 AM CDT TUE SEP 22 2015
-SHRA CAN BE EXPECTED AT KISN BETWEEN 12Z-17Z TUESDAY WITH DRY
CONDITIONS AT THE REMAINING TERMINALS. CIGS TODAY WILL RANGE FROM
9KFT TO 15KFT. A BRIEF PERIOD OF SCT CIGS AFTER 00Z
WEDNESDAY...THEN LOW VFR TO MVFR CIGS WILL DEVELOP AT ALL
TERMINALS EXCEPT KISN AFTER 06Z WEDNESDAY. SHOWERS WILL DEVELOP AT
KJMS BY 10Z WEDNESDAY ALONG WITH A VCTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JM
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
639 AM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 633 AM CDT TUE SEP 22 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS VERY LIGHT
SHOWER ACTIVITY CONTINUES ACROSS THE NORTHWEST INTO THE I-94
CORRIDOR CENTRAL. GIVEN DRY LOW LEVEL AIR IN PLACE...MUCH OF THE
PRECIPITATION IS LIKELY NOT REACHING THE GROUND. ONGOING FORECAST
BLENDED TO OBSERVED TRENDS AND A TIME LAGGED ENSEMBLE OF THE
08-10 UTC HRRR ITERATIONS WHICH CAPTURES WELLL RADAR TRENDS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 218 AM CDT TUE SEP 22 2015
FORECAST HIGHLIGHTS ARE ISOLATED TO SCATTERED SHOWERS WEST THROUGH
PORTIONS OF CENTRAL NORTH DAKOTA TUESDAY MORNING...LIFTING NORTH
THROUGH TUESDAY AFTERNOON...AND MOISTURE SURGING INTO THE JAMES
RIVER VALLEY TUESDAY NIGHT RESULTING IN INCREASING CHANCES FOR
SHOWERS AND THUNDERSTORMS.
LATEST SUITE OF SATELLITE IMAGERY/SURFACE OBSERVATIONS AND
LOCAL/REGIONAL RADAR SHOW A BAND OF ISOLATED TO SCATTERED RAIN
SHOWERS STRETCHED WEST TO EAST...FROM CENTRAL MONTANA INTO
WESTERN NORTH DAKOTA. CLOUD TOPS CONTINUE TO COOL WITH
CORRESPONDING HIGHER REFLECTIVITY AS VERTICAL MOTION/LARGE SCALE
ASCENT BEING ATTRIBUTED TO A DEPARTING 110KT JET MAX IN SOUTHERN
MANITOBA WITHE THE RIGHT ENTRANCE REGION OVER NORTHEAST MONTANA...
ISENTROPIC ASCENT PER 300K/305K PRESSURE SURFACE...AND MID LEVEL
FRONTOGENESIS. LIGHT RAIN WAS BEING REPORTED AT BEACH WITH CLOUD
BASES REPORTED AT 6KFT AND 9KFT. MODELS AGREE WITH THIS BAND
LIFTING NORTH DURING THE DAY BUT AGREEMENT ON THE PLACEMENT/AREAL
COVERAGE OF PRECIPITATION SEEMED TO BE LACKING. STARTED WITH THE
CURRENT RADAR FOR POP TRENDS...AND THEN UTILIZED A MODEL BLEND OF
THE HRRR/RAP13/NAM/GFS/ECMWF/PREVIOUS FORECAST FOR THE REMAINDER
OF THE DAY. MUCH COOLER TEMPERATURES TODAY WITH EASTERLY WINDS
BETWEEN 10 AND 25 MPH...AS HIGHS TOP OUT IN THE 60S.
WATER VAPOR SHOWS OUR NEXT UPSTREAM SHORTWAVE NOW LOCATED OVER
NORTHWESTERN NEW MEXICO. AS THIS SHORTWAVE APPROACHES TUESDAY
EVENING/NIGHT...SURFACE LOW PRESSURE OVER NORTHERN NEBRASKA WITH
AN ATTENDING WARM FRONT WILL REACH INTO SOUTHEAST NORTH DAKOTA
DAKOTA. INCREASING LOW LEVEL SOUTHEAST TO SOUTHERLY WINDS AND
MOISTURE ADVECTION WILL RESULT IN CHANCES FOR SHOWERS AND THUNDERSTORMS
MAINLY AFTER 06Z WEDNESDAY. THE GREATEST CHANCE FOR PRECIPITATION WILL
BE IN THE JAMES RIVER VALLEY THEN TAPERING OFF QUICKLY AS YOU HEAD
WEST INTO SOUTH CENTRAL NORTH DAKOTA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 218 AM CDT TUE SEP 22 2015
CONTINUED ABOVE NORMAL TEMPERATURES HIGHLIGHT THE EXTENDED
FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON A RELATIVELY COOL...BUT STILL SEASONABLE...WEDNESDAY WITH
HIGHS IN THE 60S AND 70S NORTHWEST OF THE SIGNIFICANT STORM SYSTEM
FORECAST TO IMPACT THE UPPER MISSISSIPPI VALLEY. AS OF NOW...THE
MAIN IMPACT OF HEAVY RAIN WITH THIS STORM IS EXPECTED TO REMAIN
ACROSS EASTERN SOUTH DAKOTA INTO MINNESOTA. HOWEVER...THIS WILL
HAVE TO BE MONITORED SHOULD THE FORECAST TRACK SHIFT SLIGHTLY WEST.
THEREAFTER...AN UPPER LEVEL RIDGE IS FORECAST TO BUILD INTO THE
NORTHERN PLAINS THURSDAY INTO FRIDAY...WITH SOUTHWEST FLOW ALOFT
FOR THE REMAINDER OF THE PERIOD SATURDAY ONWARD. AS A RESULT...A
WARM UP BACK INTO THE 80S IS FORECAST FOR FRIDAY AND SATURDAY.
GIVEN SOUTHWEST FLOW ALOFT SATURDAY INTO EARLY NEXT WEEK...NEAR
DAILY CHANCES FOR ISOLATED SHOWERS AND THUNDERSTORMS RETURN TO THE
FORECAST FOR THIS PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 633 AM CDT TUE SEP 22 2015
-SHRA CAN BE EXPECTED AT KISN BETWEEN 12Z-17Z TUESDAY WITH DRY
CONDITIONS AT THE REMAINING TERMINALS. CIGS TODAY WILL RANGE FROM
9KFT TO 15KFT. A BRIEF PERIOD OF SCT CIGS AFTER 00Z
WEDNESDAY...THEN LOW VFR TO MVFR CIGS WILL DEVELOP AT ALL
TERMINALS EXCEPT KISN AFTER 06Z WEDNESDAY. SHOWERS WILL DEVELOP AT
KJMS BY 10Z WEDNESDAY ALONG WITH A VCTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1216 AM CDT TUE SEP 22 2015
.UPDATE...
ISSUED AT 1216 AM CDT TUE SEP 22 2015
LATEST IR SATELLITE IMAGERY SHOWS AN EXPANDING/DEVELOPING AREA OF
MID/UPPER CLOUDS IN CENTRAL/EASTERN MONTANA...WITH REGIONAL RADAR
DEPICTING HIGHER REFLECTIVITYS IN ASSOCIATION WITH THE COOLING
TOPS/SHOWERS DEVELOPING MENTIONED ABOVE. PER 00Z NAM/GFS...VERTICAL
MOTION APPEARS TO BE DRIVEN BY A COUPLE OF THINGS. A 110KT JET
STREAK WAS LOCATED IN SOUTHERN MANITOBA WITH THE RIGHT ENTRANCE
REGION OVER NORTH CENTRAL MONTANA...ISENTROPIC LIFT ALONG THE
300K/305K PRESSURE SURFACES...AND MID LEVEL FRONTOGENESIS. THESE
FEATURES ARE FORECAST TO LIFT NORTH/NORTHEAST THROUGH 18Z TUESDAY.
THE HIGH RESOLUTION MODELS CONTINUE TO ADVERTISE A NARROW BAND OF
SHOWERS DEVELOPING IN A WEST TO EAST FASHION OVERNIGHT IN WESTERN
NORTH DAKOTA AND INTO PORTIONS OF CENTRAL NORTH DAKOTA. THIS BAND
IS FORECAST TO LIFT NORTH THROUGH TUESDAY MORNING. THE PREVIOUS
FORECAST CAPTURED THIS TREND AND WILL CONTINUE TO MAINTAIN IT AS
CURRENT DATA MENTIONED ABOVE SUPPORTS IT THROUGH THE OVERNIGHT
PERIOD INTO TUESDAY MORNING.
UPDATE ISSUED AT 940 PM CDT MON SEP 21 2015
ADJUSTED HOURLY TEMPERATURE TRENDS AS TEMPERATURES CONTINUE TO FALL
WITH COLD ADVECTION AND LOSS OF DAYTIME HEATING WITH SUNSET.
TEMPERATURES AT 9 PM CDT WERE IN THE MID 40S FAR NORTHWEST TO THE
LOWER 70S IN THE JAMES VALLEY. WINDS WERE DECREASING AND TURNING
NORTHERLY AS FORECAST. NO CHANGE IN EXPECTED LOW TEMPERATURES
TONIGHT. EVEN THOUGH TEMPERATURES FALLING NORTHWEST...INCREASE OF
CLOUD COVER OVER MONTANA AS FORECAST SHOULD BE MOVING INTO WESTERN
NORTH DAKOTA LATE THIS EVENING/OVERNIGHT. THIS SHOULD KEEP
TEMPERATURES IN THE MID TO UPPER 30S WITH ONLY A COUPLE HOURS OF
POSSIBLE PATCHY FROST IN THE NORTH.
INCREASED CHANCE OF SHOWERS IN THE WEST AFTER MIDNIGHT AS LATEST
ITERATIONS OF THE HRRR AS WELL AS THE NAM INDICATE A NARROW BAND OF
SHOWERS DEVELOPING. THIS IS A VERY PERSISTENT FEATURE IN THE MODELS
THE PAST COUPLE OF DAYS. COLLABORATED WITH SURROUNDING OFFICES WITH
MORE CONFIDENCE IN SHOWERS OCCURRING...BUT WITH ONLY LIGHT
ACCUMULATIONS EXPECTED.
UPDATE ISSUED AT 653 PM CDT MON SEP 21 2015
MAIN CHANGES THIS UPDATE WERE TO HOURLY TEMPERATURE/DEWPOINT AND
WINDS...WITH TEMPERATURES RISING ABOVE WHAT WAS EARLIER FORECAST FOR
THE AFTERNOON HOURS. BLENDED HOURLY OBSERVATIONS WITH EXPECTED
TEMPERATURES LATER THIS EVENING...AS NO CHANGES EXPECTED AT THIS
TIME. NORTHWEST WINDS SHOULD DECREASE THIS EVENING AND BECOME
NORTHERLY AS HIGH PRESSURE THAT WAS CENTERED OVER THE FRONT RANGE OF
ALBERTA PUSHES INTO THE REGION.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 308 PM CDT MON SEP 21 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER NORTHEAST MANITOBA INTO
NORTHWEST ONTARIO WITH COLD FRONT DROPPING SOUTHEASTERLY INTO
WESTERN NORTH DAKOTA. GUSTY NORTHWEST WINDS HAVE DEVELOPED IN THE
WAKE OF THE PRE-FRONTAL TROUGH...WITH TEMPERATURES COOLING BEHIND
THE FRONTAL BOUNDARY. AHEAD OF THE FRONT...80S WITH A FEW 90S ARE
BEING REPORTED. UPPER LEVEL ANALYSIS PLACES ZONAL FLOW OVER THE
AREA.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...GUSTY WEST TO
NORTHWEST WINDS WILL CONTINUE THROUGH THIS AFTERNOON AS THE FRONT
CONTINUES ITS PROGRESSION...WITH WINDS DIMINISHING IN THE EVENING.
COOL HIGH PRESSURE SETTLES OVER THE AREA OVERNIGHT...WITH
TEMPERATURES DROPPING INTO THE 30S OVER NORTHERN LOCATIONS. A FEW
LIGHT SHOWERS MAY DEVELOP LATE TONIGHT PRIMARILY OVER THE WEST AS
A WEAK SHORT WAVE SLIDING THROUGH FAST ZONAL FLOW APPROACHES THE
AREA.
ON TUESDAY...A NOTABLY COOLER DAY IS EXPECTED IN THE WAKE OF THE
AFOREMENTIONED FRONT. WITH THAT SAID...TEMPERATURES WILL TRY AND
REBOUND A BIT AS SOUTHEASTERLY LOW LEVEL FLOW INCREASES AS A
TROUGH DEVELOPS TO THE LEE OF THE ROCKIES. THIS MAY LEAD TO SOME
BREEZY CONDITIONS OVER THE SOUTHWESTERN PART OF THE STATE. LOW
CHANCES FOR SHOWERS...AND POSSIBLY A THUNDERSTORM...CONTINUE
THROUGH THE DAY AS THE RIGHT-ENTRANCE REGION OF A JET STREAK
MOVES OVER THE AREA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 308 PM CDT MON SEP 21 2015
THUNDERSTORM CHANCES AND MILD TEMPERATURES HIGHLIGHT THE EXTENDED
RANGE FORECAST.
TUESDAY NIGHT...A BROAD UPPER LEVEL WESTERN TROUGH WILL APPROACH THE
REGION...DEEPENING A SURFACE LOW NEAR THE WYOMING SOUTH DAKOTA
BORDER. IN THE OVERNIGHT HOURS AND INTO WEDNESDAY MORNING...EXPECT
SHOWERS AND THUNDERSTORMS TO DEVELOP IN SOUTH CENTRAL AND EASTERN
NORTH DAKOTA AS THE SURFACE LOW PROPAGATES TO THE EAST NORTHEAST.
SOME ELEVATED INSTABILITY AND DEEP LAYER SHEAR IN THE 35-45 KNOT
RANGE COULD LEAD TO A STRONGER STORM OR TWO.
SHOWER AND THUNDERSTORM CHANCES SHOULD LIFT NORTH THROUGH THE DAY ON
WEDNESDAY...TAPERING OFF FROM WEST TO EAST OVERNIGHT. ON THURSDAY
AFTERNOON...AN ISOLATED THUNDERSTORM WILL BE POSSIBLE IN OUR EASTERN
ZONES.
A WARMING TREND WILL TAKE PLACE THROUGH THE WEEK...WITH HIGH
TEMPERATURES REACHING INTO THE LOW TO MID 80S ACROSS THE FORECAST
AREA BY SATURDAY AFTERNOON. AS THE REGION REMAINS IN SOUTHWEST FLOW
THROUGH THE WEEKEND...CHANCES OF SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE ACROSS MOST OF THE STATE SATURDAY EVENING THROUGH MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1216 AM CDT TUE SEP 22 2015
INCREASING MID LEVEL CLOUDS WILL LEAD TO SCT/BKN CIGS BETWEEN
8KFT AND 15KFT AT ALL TERMINALS THROUGH 00Z WEDNESDAY. SOME RAIN
SHOWERS POSSIBLE AT KDIK/KISN/KMOT...HOWEVER LATEST DATA SUGGESTS
THE GREATEST POTENTIAL WOULD RESIDE AT KISN. SCATTERED SHOWERS
NEAR/AROUND KISN BETWEEN 15Z-21Z TUESDAY AND FOR NOW HAVE OPTED TO
MENTION A VCSH DURING THIS TIME. NORTHERLY WINDS ACROSS THE AERODROMES
WILL BECOME NORTHEAST THROUGH 12Z TUESDAY...THEN EASTERLY AT 10KT-20KT
FOR THE REST OF THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JJS
LONG TERM...ZH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1152 PM CDT MON SEP 21 2015
.UPDATE...
UPDATE ISSUED AT 941 PM CDT MON SEP 21 2015
THE WIND SHIFT/COLD FRONT IS NEARLY THROUGH THE FORECAST
AREA...LOCATED FROM WAHPETON TO BEMIDJI AND QUICKLY PROPAGATING
TO THE SOUTHEAST. STORMS WERE ABLE TO FIRE TO THE NORTH OF
NORTHERN MINNESOTA WHERE THE SYNOPTIC FORCING WAS STRONGER...BUT
TOO DRY ACROSS THE STATES FOR ANY DEVELOPMENT. MAIN CONCERN WILL
BE OVERNIGHT LOWS WITH DECREASING WIND SPEEDS...CLEAR SKY...AND
DEWPOINTS IN THE 30S ADVECTING INTO THE REGION. CURRENT FORECAST
DEPICTS UPPER 30S ACROSS A PORTION OF NE ND...TO NEAR 50F ACROSS
WC MN...AND THIS SEEMS REASONABLE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 234 PM CDT MON SEP 21 2015
A HOT ONE THIS AFTERNOON. MAIN COLD FRONT WITH NW WINDS LOCATED NR
LANGDON THRU DEVILS LAKE TO NR JAMESTOWN AT 19Z. TEMPS BOOSTING
TO AROUND 90 JUST EAST OF FRONT IN AREA OF WEST-SOUTHWEST WINDS.
OTHERWISE TEMPS IN THE 80S WITH A GUSTY SOUTH WIND IN THE RRV INTO
NW/WCNTRL MN. HRRR TRIES TO INDICATE SOME PRECIP AHD OF FRONT IN
FAR ERN FCST AREA NR 00Z-01Z...BUT BEMIDJI SOUNDINGS FROM GFS/NAM
INDICATE CONVECTIVE TEMPS IN THE UPPER 80S. THUS DEFINITELY FEEL
LIKE DRY FCST IS THE WAY TO GO.
TEMPS TO COOL DRAMATICALLY TONIGHT AND MUCH COOLER ON TUESDAY.
SOME MID CLOUDS WILL STREAM EAST LATE TONIGHT INTO TUESDAY...ESP
NW HALF OF THE FCST AREA. HIGH TEMPS A GOOD 20-25 DEGREES COOLER.
MAIN MID LEVEL MOISTURE SATURATION IS FOCUSED IN WARM ADVECTION
ZONE IN NW ND/SE SASK TUESDAY AND MID LEVEL MOISTURE STREAMING
EAST RUNNING INTO VERY DRY SUB CLOUD LAYER AIRMASS. THUS FEEL ANY
THREAT FOR SHOWERS WILL BE JUST WEST OF OUR CWA...AND WILL HAVE
OUR FCST AREA DRY. 12Z NAM AND ECMWF TRIES TO SPIT OUT A LITTLE
BIT OF PRECIP WITH THIS MID LEVEL MOISTURE...AND CERTAINLY CAN BE
SOME...BUT THINK IT WILL DRY UP BEFORE REACHING THE GROUND.
SUBTROPICAL PLUME OF MOISTURE FROM THE DESERT SOUTHWEST ARRIVES
INTO ERN SD/SW MN TUESDAY NIGHT AND SPREADS NORTHEAST AND NORTH AS
SOUTHERLY 850 MB JET INCREASES. MAIN INSTABILITY SURGE HOWEVER IS
MORE SO TOWARD 12Z WED IN THE FAR SOUTH. THUS FOLLOWED WFO DLH
LEAD AND SLOWED DOWN ADVANCE OF PRECIP TUES NIGHT...WITH HIGHEST
POPS AFTER 06Z WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 234 PM CDT MON SEP 21 2015
MOISTURE AXIS SHIFTS A BIT EAST ON WEDNESDAY AS MAIN UPPER LEVEL
SHORT WAVE REMAINS WELL TO SOUR SOUTH OVER NEBRASKA INTO
WEDNESDAY. KEPT POPS IN THERE FOR SCT SHRA/TSTM ACTIVITY WED INTO
THURSDAY BUT UPPER WAVE TO OUR SOUTH STARTS TO WEAKEN AND FALL
APART. THUS COVERAGE OF PRECIP NOT GREAT.
FOR THURSDAY NIGHT THROUGH MONDAY...BASICALLY LOOK TO STAY IN
SOUTHWEST FLOW AS A TROUGH DIGS DOWN THE WEST COAST. BEST MODEL
AGREEMENT COMES IN THE FRI/SAT TIME FRAME WITH THE WEATHER LOOKING
DRY AND TEMPS WARMING BACK ABOVE NORMAL. BY SUNDAY INTO MONDAY
MODELS START TO DIFFER ON THE DETAILS SO CONFIDENCE BEGINS TO
WANE. THEREFORE HAVE PRETTY MUCH GONE WITH GUIDANCE PCPN CHANCES
WHICH INDICATE SOME LOW END CHANCES. TEMPS STILL LOOK TO REMAIN
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1152 PM CDT MON SEP 21 2015
WINDS ARE DECREASING AND SKY REMAINS CLEAR. ANTICIPATE THESE
CONDITIONS TO CONTINUE THROUGH MUCH OF THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...GODON/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
849 PM CDT WED SEP 23 2015
.UPDATE...
ISSUED AT 848 PM CDT WED SEP 23 2015
SO FAR...NO CHANGES ARE NEEDED TO THE FLASH FLOOD WATCH. THROUGH
MID EVENING...THE AREAS WHERE WE HAVE RECEIVED SOME DECENT RAINFALL
ARE LOCATIONS WHERE WE DID NOT RECEIVE MUCH RAIN LAST NIGHT.
CONVERSELY...THE AREAS THAT RECEIVED POCKETS OF HEAVY RAIN LAST
NIGHT HAVE CURRENTLY BEEN DRY SLOTTED IN OUR SOUTHWEST ZONES FROM
AROUND YANKTON AND POINTS WESTWARD. THE PRECIPITATION THIS EVENING
HAS BEEN BOTTLED UP ALONG A STRIPE OF MID LEVEL THETAE MAXIMIZED
NEAR 600MB OR THE 310K LEVEL...IN OUR WESTERN ZONES BETWEEN HURON
AND CHAMBERLAIN...AND IN PARTS OF NORTHWEST IA AROUND SIOUX CITY.
THAT SAID...THE HOURLY RAINFALL RATES HAVE NOT BEEN ALL THAT
IMPRESSIVE SO FAR BECAUSE THE HEAVIEST RAINFALL BANDS ARE
TRANSIENT. TIME WILL TELL IF THIS WILL CHANGE...OR IF RAIN BANDS
WILL BEGIN TO TRAIN A BIT. FOR INSTANCE WIDESPREAD CONVECTION IS
BEGINNING TO BREAK OUT IN CENTRAL NEB WHICH SHOULD PIVOT NORTHWARD
INTO THE WESTERN HALF OF OUR FORECAST AREA AFTER MIDNIGHT. BECAUSE
OF THIS...REALLY DO NOT WANT TO ALTER THE WATCH AT THIS TIME. BY
LATE TONIGHT WE WILL BE BETTER ABLE ASCERTAIN AS TO WHETHER TO
EXTEND ANY OF THE FLASH FLOOD WATCH OR ELIMINATE IT...AS THE
RAINFALL ON THURSDAY WILL STILL BE AROUND...BUT THE HEAVY RAIN
POTENTIAL WILL BE WANING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 306 PM CDT WED SEP 23 2015
RAINFALL CONTINUES TO VERY SLOWLY LIFT TO THE NORTH ACROSS THE AREA.
AS SHORT WAVE OVER CENTRAL NEBRASKA LIFTS NORTHEAST...EXPECT SHOWER
AND THUNDERSTORMS TO BECOME WIDESPREAD ACROSS THE REGION. WITH VERY
MOIST ENVIRONMENT AND SHORT CORFIDI VECTORS...POTENTIAL FOR HEAVY
RAINFALL EXISTS. MODEL SOUNDINGS CONTINUE TO SUGGEST MOIST
ADIABATIC PROFILE THROUGH THE DEPTH OF THE TROPOSPHERE...SUGGESTING
LITTLE CHANCE FOR SEVERE WEATHER. AGREE WITH PREVIOUS FORECASTER/S
ASSESSMENT THAT MODELS ARE PLACING HEAVIEST PRECIPITATION TOO FAR
NORTH...AND THAT HEAVIEST RAINFALL WILL BE ON THE SOUTH SIDE OF
THUNDERSTORM COMPLEX. WITH SUCH A PRIMED ENVIRONMENT...WOULD EXPECT
THE POTENTIAL FOR RAINFALL RATES TO EXCEED ONE INCH PER HOUR
RATES...ESPECIALLY WITH STRONGER STORMS. WITH THIS IN MIND... HAVE
EXPANDED THE FLASH FLOOD WATCH FOR TONIGHT EASTWARD TO THE SIOUX
CITY METRO AREA.
COULD ALSO SEE SOME LIGHT FOG DEVELOP ON THE WESTERN SIDE OF THE
PRECIPITATION SHIELD. AT THIS TIME...NOT EXPECTING VISIBILITIES TO
FALL TOO LOW BECAUSE OF LINGERING CLOUD COVER SO DID NOT INCLUDE
MENTION IN GENERAL ZONE FORECAST.
AS THE UPPER WAVE DECAYS AND SLIDES SOUTHEAST THROUGH THE DAY ON
THURSDAY...SHOULD GRADUALLY PRECIPITATION DECREASE ACROSS THE AREA.
WOULD EXPECT THE STRATUS TO HANG TOUGH...AND WITH PRECIPITATION
LINGERING THROUGH THE BETTER PART OF THE DAY ACROSS NORTHWEST
IOWA...WILL LIKELY BE A STRUGGLE TO WARM. AS A RESULT...HAVE
CONTINUED TO SQUASH DIURNAL RANGE AS COMPARED TO GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 306 PM CDT WED SEP 23 2015
DURING THE BEGINNING OF THE MEDIUM RANGE...MAIN CONCERNS WILL BE
JUST HOW LONG STRATUS WILL LINGER BEHIND THE DEPARTING UPPER LOW.
LATEST GUIDANCE CONTINUES TO HINT AS WEAK SOUTHEASTERLY LOW LEVEL
FLOW THAT MAY PUSH STRATUS WESTWARD INTO THE AREA THURSDAY NIGHT.
IN ADDITION...ANY CLEARING OR THINNING SHOULD ALLOW FOR FOG
DEVELOPMENT ESPECIALLY OVER CENTRAL AND SOUTH CENTRAL SOUTH DAKOTA.
IT COULD TAKE A BIT OF TIME FOR THIS STRATUS TO DISSIPATE DURING
THE DAY...AND IT COULD KEEP TEMPERATURES COOLER THAN THE CURRENT
FORECAST.
OTHERWISE...WE WILL SCOUR OUT THE CLOUDS AND HAVE A RETURN OF WARM
SOUTHWESTERLY FLOW FOR THE WEEKEND. HIGH TEMPERATURES AGAIN LOOK TO
BE 5 TO 10 DEGREES ABOVE NORMAL FOR THE ENTIRE WEEKEND. ANY AREAS THAT
RECEIVE RAIN SHOULD DRY OUT WITH A BREEZY WIND EACH AFTERNOON.
THE NEXT CHANCE OF RAIN LOOKS TO FOCUS ITSELF VERY LATE IN THE
FORECAST AS THE MID-LVL RIDGE FLATTENS AND A DEEP TROUGH CROSSES
CENTRAL CANADA. A RATHER STRONG FRONT WILL PUSH THROUGH THE
REGION ON MONDAY...BRINGING WITH IT A RISK FOR A FEW BANDS OF
SHOWERS INTO TUESDAY. TEMPERATURES WILL BE TRICKY FOR EARLY NEXT
WEEK...BUT PATTERN WOULD SUGGEST A BRIEF COOLDOWN BELOW NORMAL FOR
A COUPLE DAYS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 628 PM CDT WED SEP 23 2015
A TROPICAL SYSTEM WILL AFFECT THE FORECAST AREA THROUGH THE TAF
PERIOD. CONFIDENCE IS NOT REAL HIGH WITH THE DETAILS OF THE
FORECAST. IN GENERAL THOUGH...THERE IS A TREND WITH BOTH THE NAM
AND RAP IN OVERDOING THE CURRENT LOW CEILING POTENTIAL RIGHT NOW.
FOR INSTANCE...BOTH MODELS ARE SHOWING WHAT WOULD BE VERY
WIDESPREAD IFR TO LIFR CEILINGS AT THIS TIME...REALLY FOR THE
ENTIRE AREA. LOOKING AT CURRENT OBSERVATIONS...THIS IS NOT
OCCURRING WITH WIDESPREAD VFR IN PLACE. THAT SAID...UNDER THE
HEAVIER SHOWERS LIKE WHAT IS OCCURRING AT KSUX RIGHT NOW...
THERE COULD BE SOME TEMPORARY IFR TO MVFR CONDITIONS WITH LOWERED
CEILINGS AND VISIBILITY. BUT OVERALL...THE GFS MODEL IS BETTER IN
SHOWING THE LOW LEVEL MOISTURE. IT TOO HOWEVER SHOWS A GENERAL
LOWERING OF THE CEILINGS THROUGH THE NIGHT LASTING INTO THURSDAY.
SINCE TIMING THE INDIVIDUAL BANDS OF RAINFALL WHICH MAY LOWER THE
CEILINGS AND VISIBILITY FOR AN HOUR OR SO IS EXTREME DIFFICULT...
WILL JUST HAVE TO ADJUST THE TAFS AS THAT OCCURS THROUGH THE NIGHT
AND THURSDAY MORNING. FOR NOW...LEFT TSRA OUT OF THE TAF SITES AS
THE ATMOSPHERE IS ACTUALLY FAIRLY STABLE OVERALL...JUST VERY
MOIST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR SDZ066-067-071.
FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR SDZ050-063>065-
068>070.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR IAZ012-020-021-
031-032.
NE...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR NEZ014.
FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR NEZ013.
&&
$$
UPDATE...MJ
SHORT TERM...
LONG TERM...DUX
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
634 PM CDT WED SEP 23 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 306 PM CDT WED SEP 23 2015
RAINFALL CONTINUES TO VERY SLOWLY LIFT TO THE NORTH ACROSS THE AREA.
AS SHORT WAVE OVER CENTRAL NEBRASKA LIFTS NORTHEAST...EXPECT SHOWER
AND THUNDERSTORMS TO BECOME WIDESPREAD ACROSS THE REGION. WITH VERY
MOIST ENVIRONMENT AND SHORT CORFIDI VECTORS...POTENTIAL FOR HEAVY
RAINFALL EXISTS. MODEL SOUNDINGS CONTINUE TO SUGGEST MOIST
ADIABATIC PROFILE THROUGH THE DEPTH OF THE TROPOSPHERE...SUGGESTING
LITTLE CHANCE FOR SEVERE WEATHER. AGREE WITH PREVIOUS FORECASTER/S
ASSESSMENT THAT MODELS ARE PLACING HEAVIEST PRECIPITATION TOO FAR
NORTH...AND THAT HEAVIEST RAINFALL WILL BE ON THE SOUTH SIDE OF
THUNDERSTORM COMPLEX. WITH SUCH A PRIMED ENVIRONMENT...WOULD EXPECT
THE POTENTIAL FOR RAINFALL RATES TO EXCEED ONE INCH PER HOUR
RATES...ESPECIALLY WITH STRONGER STORMS. WITH THIS IN MIND... HAVE
EXPANDED THE FLASH FLOOD WATCH FOR TONIGHT EASTWARD TO THE SIOUX
CITY METRO AREA.
COULD ALSO SEE SOME LIGHT FOG DEVELOP ON THE WESTERN SIDE OF THE
PRECIPITATION SHIELD. AT THIS TIME...NOT EXPECTING VISIBILITIES TO
FALL TOO LOW BECAUSE OF LINGERING CLOUD COVER SO DID NOT INCLUDE
MENTION IN GENERAL ZONE FORECAST.
AS THE UPPER WAVE DECAYS AND SLIDES SOUTHEAST THROUGH THE DAY ON
THURSDAY...SHOULD GRADUALLY PRECIPITATION DECREASE ACROSS THE AREA.
WOULD EXPECT THE STRATUS TO HANG TOUGH...AND WITH PRECIPITATION
LINGERING THROUGH THE BETTER PART OF THE DAY ACROSS NORTHWEST
IOWA...WILL LIKELY BE A STRUGGLE TO WARM. AS A RESULT...HAVE
CONTINUED TO SQUASH DIURNAL RANGE AS COMPARED TO GUIDANCE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 306 PM CDT WED SEP 23 2015
DURING THE BEGINNING OF THE MEDIUM RANGE...MAIN CONCERNS WILL BE
JUST HOW LONG STRATUS WILL LINGER BEHIND THE DEPARTING UPPER LOW.
LATEST GUIDANCE CONTINUES TO HINT AS WEAK SOUTHEASTERLY LOW LEVEL
FLOW THAT MAY PUSH STRATUS WESTWARD INTO THE AREA THURSDAY NIGHT.
IN ADDITION...ANY CLEARING OR THINNING SHOULD ALLOW FOR FOG
DEVELOPMENT ESPECIALLY OVER CENTRAL AND SOUTH CENTRAL SOUTH DAKOTA.
IT COULD TAKE A BIT OF TIME FOR THIS STRATUS TO DISSIPATE DURING
THE DAY...AND IT COULD KEEP TEMPERATURES COOLER THAN THE CURRENT
FORECAST.
OTHERWISE...WE WILL SCOUR OUT THE CLOUDS AND HAVE A RETURN OF WARM
SOUTHWESTERLY FLOW FOR THE WEEKEND. HIGH TEMPERATURES AGAIN LOOK TO
BE 5 TO 10 DEGREES ABOVE NORMAL FOR THE ENTIRE WEEKEND. ANY AREAS THAT
RECEIVE RAIN SHOULD DRY OUT WITH A BREEZY WIND EACH AFTERNOON.
THE NEXT CHANCE OF RAIN LOOKS TO FOCUS ITSELF VERY LATE IN THE
FORECAST AS THE MID-LVL RIDGE FLATTENS AND A DEEP TROUGH CROSSES
CENTRAL CANADA. A RATHER STRONG FRONT WILL PUSH THROUGH THE
REGION ON MONDAY...BRINGING WITH IT A RISK FOR A FEW BANDS OF
SHOWERS INTO TUESDAY. TEMPERATURES WILL BE TRICKY FOR EARLY NEXT
WEEK...BUT PATTERN WOULD SUGGEST A BRIEF COOLDOWN BELOW NORMAL FOR
A COUPLE DAYS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 628 PM CDT WED SEP 23 2015
A TROPICAL SYSTEM WILL AFFECT THE FORECAST AREA THROUGH THE TAF
PERIOD. CONFIDENCE IS NOT REAL HIGH WITH THE DETAILS OF THE
FORECAST. IN GENERAL THOUGH...THERE IS A TREND WITH BOTH THE NAM
AND RAP IN OVERDOING THE CURRENT LOW CEILING POTENTIAL RIGHT NOW.
FOR INSTANCE...BOTH MODELS ARE SHOWING WHAT WOULD BE VERY
WIDESPREAD IFR TO LIFR CEILINGS AT THIS TIME...REALLY FOR THE
ENTIRE AREA. LOOKING AT CURRENT OBSERVATIONS...THIS IS NOT
OCCURRING WITH WIDESPREAD VFR IN PLACE. THAT SAID...UNDER THE
HEAVIER SHOWERS LIKE WHAT IS OCCURRING AT KSUX RIGHT NOW...
THERE COULD BE SOME TEMPORARY IFR TO MVFR CONDITIONS WITH LOWERED
CEILINGS AND VISIBILITY. BUT OVERALL...THE GFS MODEL IS BETTER IN
SHOWING THE LOW LEVEL MOISTURE. IT TOO HOWEVER SHOWS A GENERAL
LOWERING OF THE CEILINGS THROUGH THE NIGHT LASTING INTO THURSDAY.
SINCE TIMING THE INDIVIDUAL BANDS OF RAINFALL WHICH MAY LOWER THE
CEILINGS AND VISIBILITY FOR AN HOUR OR SO IS EXTREME DIFFICULT...
WILL JUST HAVE TO ADJUST THE TAFS AS THAT OCCURS THROUGH THE NIGHT
AND THURSDAY MORNING. FOR NOW...LEFT TSRA OUT OF THE TAF SITES AS
THE ATMOSPHERE IS ACTUALLY FAIRLY STABLE OVERALL...JUST VERY
MOIST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR SDZ066-067-071.
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SDZ050-063>065-
068>070.
MN...NONE.
IA...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR IAZ012-020-021-
031-032.
NE...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR NEZ014.
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NEZ013.
&&
$$
SHORT TERM...
LONG TERM...DUX
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
807 PM CDT WED SEP 23 2015
.UPDATE...
Updated the forecast to increase cloud cover across the northern
and western portions of the forecast area based on the latest
observations/trends. A line of showers and thunderstorms extended
from near Big Spring to Fort Stockton, and this line continues to
move east southeast at 20 mph. This area of precipitation will
start to outrun the moisture/instability axis to our west during
the next few hours, and it should gradually weaken as it
approaches our western counties. However, it may hold together
long enough to give areas west of an Ozona to Robert Lee to
Haskell line some light rainfall, where isolated showers were
added to the forecast through 1 AM. The latest HRRR supports this
scenario as well.
&&
.PREV DISCUSSION... /ISSUED 720 PM CDT WED SEP 23 2015/
AVIATION...
/00Z TAFS/
A line of showers and thunderstorms continues to march east across
the Permian Basin this evening, but should rapidly weaken as it
approaches the Concho Valley as it moves into a much more stable
environment. Scattered to broken mid/high clouds are expected
overnight and early Thursday, with a diurnal cu field of 6-7 kft
developing by midday. Expect light southeast winds overnight,
becoming southerly late tonight through 18z, shifting to the east
Thursday afternoon.
Johnson
PREV DISCUSSION... /ISSUED 342 PM CDT WED SEP 23 2015/
SHORT TERM...
(Tonight and Thursday)
Dry and warm conditions will continue through Thursday, with
slightly above normal temperatures continuing. Showers and a few
thunderstorms have develop across the higher terrain of southeastern
New Mexico this afternoon, with showers also extending northeast
into the southern Panhandle and western Oklahoma. This activity has
developed in association with a weak mid level trough over the
southern Rockies and upslope flow across the higher terrain. Some
of this activity may clip extreme northwest portions of the Big
Country through early evening but most of it will stay north and
west of the area, so no POPs were added at this time.
The latest 4km Texas Tech WRF develops scattered convection across
the area on Thursday, while the NAM, GFS remain dry. Cannot discount
the WRF entirely, as the ridge begins weakening and aforementioned
mid level trough sinks south across eastern New Mexico and far west
Texas. Any convection that does develop will most likely remain west
of the area and decided to keep the forecast dry for now, which
matches well with neighboring offices. Lows tonight will be in the
60s, with highs Thursday near 90 degrees.
LONG TERM...
(Thursday Night through Wednesday)
Still considering the chance of rain for Friday. GFS and the TTU
WRF have been indicating a small chance of showers and storms for
Friday across portions of West Central Texas, as a weak cold front
moves into the area. Instability is a little marginal and the best
lift may be early as a weak shortwave rotates through the area. At
this point, not sure there is enough there to warrant a mention
quite yet, but if these trends continue, may need to insert PoPs
at some point later this week.
Upper level ridge remains off to the west for much of the extended
time frame, while an upper level low develops off to the east.
This places West Central Texas largely in northerly flow aloft for
much of next week. Should have a series of weak cold fronts move
across the area. No cold air coming, but perhaps something closer
to normal than we have been the last few weeks.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 67 91 68 88 / 10 0 5 10
San Angelo 66 91 66 90 / 10 0 5 10
Junction 63 90 65 90 / 5 0 5 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Doll
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1048 AM CDT TUE SEP 22 2015
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
12Z SOUNDINGS SHOW PW VALUES NEAR 1.50 INCHES AT CRP AND 1.20
INCHES AT LCH. SOUNDINGS SHOW MAX TEMPS IN THE UPPER 80S/LOWER 90S
OVER SE TX THIS AFTN AND CURRENT TEMPS ARE 1 TO 2 DEGREES COOLER
AT THIS TIME COMPARED TO YESTERDAY. DRIER AIR WILL MOVE INTO SE
TX FROM THE EAST THIS AFTN WHICH SHOULD AID IN HEATING. EXTREME
WESTERN ZONES ON THE CUSP OF DEEPER MSTR SO WILL LET THE ISO POPS
RIDE THIS AFTN. OTHER THAN SOME MINOR TWEAKS TO SKY GRIDS AND
TEMPS...WILL LET THE PREV FCST RIDE. 43
&&
.PREV DISCUSSION... /ISSUED /
AVIATION...
ANY FOG WILL BURN OFF BEFORE 15Z. REST OF THE DAY VFR. COULD SEE A
SHRA/TSRA DEVELOP IN THE CLL AREA THIS AFTERNOON... BUT CONFIDENCE
TOO LOW TO MENTION IN THE TAF. COULD SEE MORE FOG DEVELOP LATER ON
TONIGHT AND ON INTO EARLY TOMORROW MORNING. 42
PREV DISCUSSION...
DISCUSSION...
SEEING HIGH CLOUDS MOVING FROM THE NW TO THE SE TONIGHT WITH SOME
PATCHY FOG AS WELL AT THE USUAL SPOTS. ISOLATED SHRA WELL OFFSHORE
MOVING W/SW. EXPECT TO SEE HIGH CLOUDS CONTINUE TO STREAM ACROSS
TODAY...BUT WILL SEE PLENTY OF SUN. MAX TEMPS SHOULD BE VERY SIMILAR
TO YESTERDAY.
WILL HAVE A SLIGHT CHC POP ACROSS WESTERN AREAS WHERE HEATING AND
SLIGHTLY DEEPER MOISTURE LEVELS WILL LIKELY PRODUCE VERY ISOLATED
SHRA THIS AFTERNOON. THIS IS SUPPORTED BY THE LATEST HRRR RUN. WED
LOOKS DRIER ACROSS THE AREA WITH PRECIP WATER VALUES FALLING TO
BELOW AN INCH AREAWIDE. ON THU SLIGHTLY DEEPER MOISTURE LEVELS
WILL ARRIVE FROM THE EAST. A WEAK UPPER LEVEL DISTURBANCE COUPLED
WITH THIS DEEPER MOISTURE WILL LIKELY LEAD TO A CHANCE OF
SHRA/TSTMS ACROSS SE AREAS ON FRI. SO...HAVE ADJUSTED POPS UPWARD
FOR FRI. EXPECT SLIGHT CHC POPS NEAR THE COAST THIS WEEKEND AND
MAINLY DRY INLAND.
AS MID/UPPER HEIGHTS FALL LATER THIS WEEK AND THIS WEEKEND EXPECT
MAX TEMPS TO DECREASE. SOME SIGNIFICANT DIFFERENCES EMERGE BETWEEN
THE GFS AND ECMWF BY SUN. THE ECMWF HAS THE MID/UPPER LOW WELL TO
THE SW OF THE GFS...CENTERED NEAR S TX...WHILE THE GFS HAS THIS
FEATURE NEAR NE TX. BOTH MODELS ARE ADVERTISING A SFC LOW MOVING
INTO THE CENTRAL GULF FROM THE YUCATAN IN THE MON-WED TIME FRAME.
AFTER TUE/WED...THEY DIVERGE CONCERNING THE MOVEMENT OF THE SFC
LOW. SO...STAY TUNED AS THERE IS LOW CONFIDENCE CONCERNING THE RAIN
CHCS AT THE END OF THE FORECAST PD AND INTO NEXT WEEK. 33
MARINE...
LIGHT TO MODERATE EAST TO NORTHEAST WINDS WILL PERSIST FOR MUCH OF
THE WEEK WITH HIGH PRESSURE STRETCHING FROM THE EAST COAST INTO
EASTERN TEXAS AND LOWER PRESSURE NEAR THE YUCATAN PENINSULA. MAY SEE
A WEAK SEABREEZE EACH AFTERNOON PRODUCING A FEW HOURS OF SOUTHEAST
WINDS. WINDS/SEAS SHOULD REMAIN BELOW CAUTION CRITERIA THROUGH
SATURDAY NIGHT. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 95 70 93 68 93 / 20 0 0 0 0
HOUSTON (IAH) 93 68 91 69 91 / 10 0 0 0 0
GALVESTON (GLS) 89 78 88 77 87 / 10 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
618 AM CDT TUE SEP 22 2015
.AVIATION...
ANY FOG WILL BURN OFF BEFORE 15Z. REST OF THE DAY VFR. COULD SEE A
SHRA/TSRA DEVELOP IN THE CLL AREA THIS AFTERNOON... BUT CONFIDENCE
TOO LOW TO MENTION IN THE TAF. COULD SEE MORE FOG DEVELOP LATER ON
TONIGHT AND ON INTO EARLY TOMORROW MORNING. 42
&&
.PREV DISCUSSION...
DISCUSSION...
SEEING HIGH CLOUDS MOVING FROM THE NW TO THE SE TONIGHT WITH SOME
PATCHY FOG AS WELL AT THE USUAL SPOTS. ISOLATED SHRA WELL OFFSHORE
MOVING W/SW. EXPECT TO SEE HIGH CLOUDS CONTINUE TO STREAM ACROSS
TODAY...BUT WILL SEE PLENTY OF SUN. MAX TEMPS SHOULD BE VERY SIMILAR
TO YESTERDAY.
WILL HAVE A SLIGHT CHC POP ACROSS WESTERN AREAS WHERE HEATING AND
SLIGHTLY DEEPER MOISTURE LEVELS WILL LIKELY PRODUCE VERY ISOLATED
SHRA THIS AFTERNOON. THIS IS SUPPORTED BY THE LATEST HRRR RUN. WED
LOOKS DRIER ACROSS THE AREA WITH PRECIP WATER VALUES FALLING TO
BELOW AN INCH AREAWIDE. ON THU SLIGHTLY DEEPER MOISTURE LEVELS
WILL ARRIVE FROM THE EAST. A WEAK UPPER LEVEL DISTURBANCE COUPLED
WITH THIS DEEPER MOISTURE WILL LIKELY LEAD TO A CHANCE OF
SHRA/TSTMS ACROSS SE AREAS ON FRI. SO...HAVE ADJUSTED POPS UPWARD
FOR FRI. EXPECT SLIGHT CHC POPS NEAR THE COAST THIS WEEKEND AND
MAINLY DRY INLAND.
AS MID/UPPER HEIGHTS FALL LATER THIS WEEK AND THIS WEEKEND EXPECT
MAX TEMPS TO DECREASE. SOME SIGNIFICANT DIFFERENCES EMERGE BETWEEN
THE GFS AND ECMWF BY SUN. THE ECMWF HAS THE MID/UPPER LOW WELL TO
THE SW OF THE GFS...CENTERED NEAR S TX...WHILE THE GFS HAS THIS
FEATURE NEAR NE TX. BOTH MODELS ARE ADVERTISING A SFC LOW MOVING
INTO THE CENTRAL GULF FROM THE YUCATAN IN THE MON-WED TIME FRAME.
AFTER TUE/WED...THEY DIVERGE CONCERNING THE MOVEMENT OF THE SFC
LOW. SO...STAY TUNED AS THERE IS LOW CONFIDENCE CONCERNING THE RAIN
CHCS AT THE END OF THE FORECAST PD AND INTO NEXT WEEK. 33
MARINE...
LIGHT TO MODERATE EAST TO NORTHEAST WINDS WILL PERSIST FOR MUCH OF
THE WEEK WITH HIGH PRESSURE STRETCHING FROM THE EAST COAST INTO
EASTERN TEXAS AND LOWER PRESSURE NEAR THE YUCATAN PENINSULA. MAY SEE
A WEAK SEABREEZE EACH AFTERNOON PRODUCING A FEW HOURS OF SOUTHEAST
WINDS. WINDS/SEAS SHOULD REMAIN BELOW CAUTION CRITERIA THROUGH
SATURDAY NIGHT. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 95 70 93 68 93 / 20 0 0 0 0
HOUSTON (IAH) 93 68 91 69 91 / 10 0 0 0 0
GALVESTON (GLS) 89 78 88 77 87 / 10 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
335 AM CDT TUE SEP 22 2015
.DISCUSSION...
SEEING HIGH CLOUDS MOVING FROM THE NW TO THE SE TONIGHT WITH SOME
PATCHY FOG AS WELL AT THE USUAL SPOTS. ISOLATED SHRA WELL OFFSHORE
MOVING W/SW. EXPECT TO SEE HIGH CLOUDS CONTINUE TO STREAM ACROSS
TODAY...BUT WILL SEE PLENTY OF SUN. MAX TEMPS SHOULD BE VERY SIMILAR
TO YESTERDAY.
WILL HAVE A SLIGHT CHC POP ACROSS WESTERN AREAS WHERE HEATING AND
SLIGHTLY DEEPER MOISTURE LEVELS WILL LIKELY PRODUCE VERY ISOLATED
SHRA THIS AFTERNOON. THIS IS SUPPORTED BY THE LATEST HRRR RUN. WED
LOOKS DRIER ACROSS THE AREA WITH PRECIP WATER VALUES FALLING TO
BELOW AN INCH AREAWIDE. ON THU SLIGHTLY DEEPER MOISTURE LEVELS
WILL ARRIVE FROM THE EAST. A WEAK UPPER LEVEL DISTURBANCE COUPLED
WITH THIS DEEPER MOISTURE WILL LIKELY LEAD TO A CHANCE OF
SHRA/TSTMS ACROSS SE AREAS ON FRI. SO...HAVE ADJUSTED POPS UPWARD
FOR FRI. EXPECT SLIGHT CHC POPS NEAR THE COAST THIS WEEKEND AND
MAINLY DRY INLAND.
AS MID/UPPER HEIGHTS FALL LATER THIS WEEK AND THIS WEEKEND EXPECT
MAX TEMPS TO DECREASE. SOME SIGNIFICANT DIFFERENCES EMERGE BETWEEN
THE GFS AND ECMWF BY SUN. THE ECMWF HAS THE MID/UPPER LOW WELL TO
THE SW OF THE GFS...CENTERED NEAR S TX...WHILE THE GFS HAS THIS
FEATURE NEAR NE TX. BOTH MODELS ARE ADVERTISING A SFC LOW MOVING
INTO THE CENTRAL GULF FROM THE YUCATAN IN THE MON-WED TIME FRAME.
AFTER TUE/WED...THEY DIVERGE CONCERNING THE MOVEMENT OF THE SFC
LOW. SO...STAY TUNED AS THERE IS LOW CONFIDENCE CONCERNING THE RAIN
CHCS AT THE END OF THE FORECAST PD AND INTO NEXT WEEK. 33
&&
.MARINE...
LIGHT TO MODERATE EAST TO NORTHEAST WINDS WILL PERSIST FOR MUCH OF
THE WEEK WITH HIGH PRESSURE STRETCHING FROM THE EAST COAST INTO
EASTERN TEXAS AND LOWER PRESSURE NEAR THE YUCATAN PENINSULA. MAY SEE
A WEAK SEABREEZE EACH AFTERNOON PRODUCING A FEW HOURS OF SOUTHEAST
WINDS. WINDS/SEAS SHOULD REMAIN BELOW CAUTION CRITERIA THROUGH
SATURDAY NIGHT. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 95 70 93 68 93 / 10 0 0 0 0
HOUSTON (IAH) 94 68 92 69 91 / 10 0 0 0 0
GALVESTON (GLS) 89 78 88 77 87 / 0 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1258 AM CDT TUE SEP 22 2015
.AVIATION.../06Z TAFS/
VFR CONDITIONS SHOULD PREVAIL AT ALL SITES AS LOW LEVELS REMAIN
RELATIVELY DRY ON THE BACKSIDE OF YESTERDAYS MIDLEVEL TROUGH.
HOWEVER...THE LATEST RUN OF THE HRRR SHOWED IFR-MVFR CIGS AROUND
13-14Z FOR SAT/SSF...SO RETAINED SCT020 CIGS THERE. HIGH CLOUD
DECKS WILL HANG AROUND TOMORROW AS MOISTURE FROM A DISSIPATING
PACIFIC TROPICAL DEPRESSION IN NM AND W TX CIRCULATES AROUND HIGH
PRESSURE. SE WINDS SHOULD REMAIN BELOW 10 KT EXCEPT AT DRT WHERE
BRIEF GUSTS TO 15-20 KTS WILL OCCUR.
&&
.PREV DISCUSSION... /ISSUED 647 PM CDT MON SEP 21 2015/
AVIATION...
VFR THROUGH THE FORECAST PERIOD. PLENTY OF HIGH LEVEL MOISTURE
COMING IN FROM THE NW WILL BE AROUND FOR THE NEXT 24 HOURS.
ALTHOUGH THE RH TIME SECTIONS DO NOT SHOW MUCH IN THE WAY OF LOW
CLOUDS TUE MORNING...ADDED IN MENTION OF SCT015 AT BOTH SAT AND
SSF IN CASE WE DO INDEED GET SOME STRATUS IN THE MORNING AS WE
HAVE SEEN THE LAST SEVERAL MORNINGS. FEW CU FOR TUE AFTERNOON WITH
OVERALL A VERY LIGHT PRESSURE GRADIENT AND MOST E/SE WINDS LESS
THAN 10 KT.
PREV DISCUSSION... /ISSUED 233 PM CDT MON SEP 21 2015/
SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
NO IMPACTFUL WEATHER HIGHLIGHTS FOR THE SHORT TERM WITH CONTINUED
ABOVE AVERAGE TEMPERATURES AND NO RAIN CHANCES.
TEMPERATURES THIS AFTERNOON ARE IN THE LOW TO MID 90S ACROSS THE
REGION UNDER CLEAR TO PARTLY CLOUDY SKIES. READINGS WILL TOP OUT
AROUND 2-5F DEGREES ABOVE NORMAL THIS AFTERNOON COMPARED TO
CLIMATOLOGICAL NORMALS FOR THIS TIME OF THE YEAR. THESE HIGHER
READINGS ARE DUE TO A LOW TO MID-LVL RIDGE OVER THE REGION THAT IS
FLANKED BY A DEEPER EASTERN CONUS TROUGH AND TROPICAL DEPRESSION
16-E THAT IS ENTERING THE DESERT SOUTHWEST. ONLY IMPACTS THE
REGION WILL SEE FROM THE TROPICAL DEPRESSION WILL BE SOME HIGH
CIRRUS CLOUD BLOW-OFF AS THE LOWER-LVL MOISTURE WILL BE SHUNTED
NORTH AROUND THE RIDGE. THIS RIDGE OF HIGHER PRESSURE WILL KEEP
RAIN CHANCES NILL THROUGH THE PERIOD. THE ABOVE NORMAL
TEMPERATURES WILL CONTINUE INTO TUESDAY.
LONG TERM (WEDNESDAY THROUGH MONDAY)...
WITH THE RIDGE IN CONTROL THROUGH THURSDAY AND THE REGION LIKELY
BEING ON THE WEST SIDE OF A DEVELOPING CUT-OFF CYCLONIC GYRE OVER
THE GULF OVER THE WEEKEND...LITTLE TO NO IMPACT WEATHER IS
EXPECTED THROUGH THE NEXT WEEK.
ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THURSDAY AS THE
CURRENT LONGWAVE ERN CONUS TROUGH CUTS OFF FROM THE MAIN JET
STREAM AND MEANDERS OVER THE SOUTHEAST. AS THIS OCCURS...
ADDITIONAL SHORTWAVE TROUGHS MAY BE ABLE TO PIVOT SOUTH ON ITS
PERIPHERY INTO THE SOUTHERN PLAINS AS THE RIDGE RETROGRADES WEST
TOWARDS BAJA. LONG TERM MODELS OF GFS/EC/GEM AGREE ON THIS OVERALL
SOLUTION BUT THE SUBTLETIES OF PWATS AND EXACT SHORTWAVE TROUGH
PLACEMENT LEAD TO VARYING RAIN CHANCES FRIDAY AND SATURDAY. WITH
THIS ADVERTISED PATTERN...TEMPERATURES WILL BE ON THE DOWN TREND
WITH READINGS BACK TO NEAR NORMAL. THE QUESTION WILL BE ON THE
SHORTWAVE TROUGH LOCATIONS AND IF ENOUGH MOISTURE WILL BE PRESENT.
AT THIS TIME...FEEL PWATS OF 1.2-1.4" MAY BE LOW ENOUGH WITH THE
WEAK FORCING AND LIKELY ON THE SUBSIDENT SIDE OF THE MAIN CUT-OFF
TROUGH TO WARRANT RAIN MENTION. HAVE HELD RAIN CHANCES IN THE
10-15% RANGE FRI/SAT FOR NOW AND WILL SEE HOW MODELS EVOLVE THE
CUT-OFF GYRE THROUGH EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 94 72 94 69 93 / 0 0 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 94 68 93 65 92 / 0 0 0 0 0
NEW BRAUNFELS MUNI AIRPORT 95 69 94 67 93 / 0 0 0 0 0
BURNET MUNI AIRPORT 92 70 91 68 91 / 0 0 0 0 0
DEL RIO INTL AIRPORT 94 71 93 70 93 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 94 70 93 67 91 / 0 0 0 0 0
HONDO MUNI AIRPORT 94 68 93 66 93 / 0 0 0 0 0
SAN MARCOS MUNI AIRPORT 94 69 92 67 91 / 0 0 0 0 0
LA GRANGE - FAYETTE REGIONAL 93 69 92 67 91 / 0 0 0 0 0
SAN ANTONIO INTL AIRPORT 94 72 92 70 92 / 0 0 0 0 0
STINSON MUNI AIRPORT 95 71 94 69 93 / 0 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...LH
SYNOPTIC/GRIDS...HAMPSHIRE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
213 AM MDT THU SEP 24 2015
.UPDATE...
ISSUED AT 850 PM MDT WED SEP 23 2015
REMOVED ANY MENTION OF RAINFALL FROM THE FORECAST UNTIL TOMORROW
AFTERNOON WHEN A BAND OF MOISTURE AND LIFT FROM THE UPPER LEVEL
TROUGH OVER NEBRASKA ROTATE SOUTH OVER GRAHAM AND NORTON COUNTIES.
BETWEEN NOW AND THEN THE ENVIRONMENT WILL BE VERY DRY AND LITTLE
TO NO LIFT. ANY STORMS WHICH DEVELOP SHOULD DO SO JUST EAST OF THE
AREA WHERE THE ENVIRONMENTAL MOISTURE WILL BE BETTER.
ADJUSTED THE PLACEMENT OF THE THICKEST FOG FOR TONIGHT TO MORE
OVER THE WESTERN HALF OR SO OF THE AREA. WOULD NOT BE SURPRISED TO
SEE FOG DEVELOP OVER THE NORTHEAST PART OF THE AREA WHERE THERE
WERE SCATTERED SHOWERS EARLIER THIS EVENING...AS WELL AS OVER THE
SOUTHWEST PART OF THE AREA. MODELS SEEM TO LOOSELY AGREE THE
DENSEST FOG WILL BE WEST OF HIGHWAY 25 AND NORTH OF I-70 WHERE THE
NORTHERLY WINDS WILL BE BRINGING IN MID 50S DEW POINTS FROM
WESTERN NEBRASKA ALONG WITH COOLER AIR. VISIBILITIES AROUND A MILE
OR TWO CAN BE EXPECTED AROUND SUNRISE FOR THIS PART OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 226 PM MDT WED SEP 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CLOSED UPPER LOW MOVING INTO NORTHCENTRAL NEBRASKA...WITH TROUGH
AXIS EXTENDING SOUTH ACROSS OUR CWA INTO SOUTHEAST COLORADO. STRONG
PV HEIGHT ANOMALY IS OVER OUR CWA ASSOCIATED WITH SW QUADRANT OF
CLOSED LOW. CONVERGENCE ALONG SURFACE TROUGH AXIS CURRENTLY SOUTH OF
I-70 AND MID LEVEL ROTATION ALONG SOUTHERN EDGE OF TROUGH HAS AIDED
IN THUNDERSTORM INITIATION ALONG AXIS OF STEEP LAPSE RATES/MODERATE
CAPE.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY WILL CONTINUE TO BE
POSSIBLE ALONG SURFACE TROUGH THIS ACTIVITY...POSSIBLY DEVELOPING
INTO NW KANSAS. HI RES GUIDANCE SHOWS THIS ACTIVITY REMAINING
ROUGHLY ALONG AND SOUTH OF I-70 ALONG TROUGH AXIS. TREND SHOULD BE
FOR THIS ACTIVITY TO TRANSITION TO THE SOUTH AS TROUGH AXIS SLIDES
SOUTH AND LOW LEVEL STABILIZE OVER OUR CWA. SHOWERS/ISOLATED
THUNDERSTORMS IN THE EASTERN CWA MAY CONTINUE TO LINGER THOUGH THE
NIGHT AS MOISTURE/MID LEVEL ENERGY CONTINUES TO ROTATE AROUND THE
MID LEVEL CLOSED LOW IN NEBRASKA. CAPE AXIS OF ROUGHLY 2000 J/KG
WILL SUPPORT SOME STRONGER UPDRAFTS WITH MARGINAL HAIL/WIND THREAT.
SHEAR IS UNIMPRESSIVE WITH EFFECTIVE SHEER BELOW 20KT...SO SEVERE
THREAT IS LIMITED THIS AFTERNOON AND EVENING.
OTHER CONCERN FOR TONIGHT WILL BE POTENTIAL FOR FOG DEVELOPMENT
AS SURFACE HIGH PRESSURE BUILDS IN TO THE WESTERN PART OF OUR CWA
AND SURFACE LOW SHIFTS EAST. WINDS WILL DECREASE BETWEEN THESE
FEATURES AND WITH CLEARING SKIES COMBINE WITH ABUNDANT LOW LEVEL
MOISTURE TO FOR FOG DEVELOPMENT ACROSS AT LEAST THE WESTERN PARTS
OF OUR CWA. CONFIDENCE IN A DENSE FOG EVENT IS LOWERED BY SHIFT IN
WINDS TO THE NW AROUND 12Z...WHICH COULD BRING DRIER AIR AND
BETTER BL MIXING. IN ANY CASE WITH SIGNAL DEPICTED BY SREF
PROBABILITIES AND NAM/RAP CONFIDENCE WAS HIGH ENOUGH TO ADD
PATCHY/AREAS MENTION TO MOST OF CWA.
THURSDAY...AS CLOSED LOW MEANDERS EASTWARD AND MEAN TROUGH AXIS
SHIFTS SOUTHEAST SUBSIDENCE AND A DEEP DRY MID LEVEL AIR MASS
WILL OVERSPREAD OUR CWA. BY LATE THURSDAY AFTERNOON A LOBE OF
VORTICITY MAY ROTATE AROUND BACK EDGE OF CLOSED LOW INTO OUR
CWA. CONSIDERING THE DRY NATURE OF THE AIR MASS...CONFIDENCE IN
MEASURABLE PRECIP WAS TOO LOW TO INCLUDE MENTION THURSDAY
AFTERNOON DESPITE SOME FORCING ALOFT AND STEEP LAPSE RATES. THERE
IS A SPLIT BETWEEN GUIDANCE REGARDING TEMPS AS SOME GUIDANCE SHOWS
REINFORCING CAA BEHIND UPPER LOW OVERSPREADING OUR CWA...WHILE
OTHER GUIDANCE SUPPORTS WAA AND HIGH PRESSURE BEGINNING TO BREAK
DOWN FROM THE WEST. I BUMPED UP TEMPS IN THE WEST (EASTERN
COLORADO) TO THE MID 80S...WITH HIGHS ELSEWHERE GENERALLY IN THE
UPPER 70S/NEAR 80F. THIS ISN`T FAR FROM MOST CONSENSUS SOLUTIONS.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 212 AM MDT THU SEP 24 2015
AN UPPER LEVEL RIDGE WILL BE THE DOMINATE WEATHER FEATURE FOR SUNDAY
AND MONDAY. THE MAIN JET ENERGY AND LIFT WILL REMAIN WELL TO THE
NORTH OF THE CENTRAL PLAINS...SO DRY WEATHER AND WARM CONDITIONS IN
THE MID TO UPPER 80S ARE EXPECTED.
THE NEXT CHANCE FOR SOME PRECIPITATION WOULD BE TUESDAY EVENING AND
OVERNIGHT AS THE GFS DEPICTS A TROUGH EXTENDING INTO THE MIDWESTERN
STATES THAT COULD PROVIDE THE NECESSARY LIFT...HOWEVER THE ECMWF
INDICATES AN INCREASING AMPLITUDE RIDGE OVER THE HIGH PLAINS REGION.
THE ECMWF RUN CONTINUES TO BE THE MOST CONSISTENT WITH PREVIOUS
RUNS...HOWEVER THE GFS CONTINUES TO FLUCTUATE AND DISAGREE WITH THE
POSITIONING AND STRENGTH OF THE UPPER LEVEL TROUGH THAT WILL AFFECT
THE UPPER MIDWEST. THEREFORE...CONFIDENCE IN THE ECMWF IS BETTER
THAN THE OTHER MODELS AT THE MOMENT. MODEL CONSENSUS DID PLACE SOME
PRECIPITATION IN THE FORECAST DESPITE THE ECMWF KEEPING THE WEATHER
DRY ACROSS THE TRI STATE AREA. CONSENSUS MAY BE PICKING UP ON
PRECIPITATION GENERATED BASED ON HEIGHT FALLS ASSOCIATED WITH THE
APPROACHING TROUGH FROM THE GFS/DGEX...AND CANADIAN HAD A SHORTWAVE
TROUGH DEVELOPING ALONG THE COLORADO FRONT RANGE IN THE LAST VALID
PERIOD 00Z WEDNESDAY. THE CONFLICTING INFORMATION IN MODEL
FORECASTS IS LEADING TO LOW CONFIDENCE AT THIS POINT FOR
PRECIPITATION CHANCES TUESDAY NIGHT AND WEDNESDAY...SO DID NOT MAKE
CHANGES TO THE CONSENSUS AND KEPT SLIGHT CHANCE MENTION.
DIFFERENCES IN THE TROUGH AND RIDGE POSITIONING IN THE MODELS ALSO
MAKES THE TEMPERATURE FORECAST DIFFICULT. IF THE GFS IS CORRECT
WITH THE TROUGH POSITION AND PRECIPITATION LOCATION...TEMPERATURES
ARE LIKELY TO BE COOLER WITH THE INFLUX OF A NORTHERN AIR MASS.
HOWEVER IF A STRONG RIDGE REMAINS IN PLACE AS GIVEN BY THE
ECMWF...SEASONABLY WARM TEMPERATURES COULD RESULT. AGAIN GIVEN THE
UNCERTAINTY...DID NOT MAKE ANY CHANGES TO THE MODEL CONSENSUS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1127 PM MDT WED SEP 23 2015
VFR TO MVFR CONDITIONS FORECAST FOR THE 6Z TAFS. MAIN ISSUE WILL
BE HOW LOW VISIBILITIES WILL FALL AROUND SUNRISE DUE TO THE MOIST
LOW LEVELS. SOUNDINGS FOR KGLD ARE MORE FAVORABLE FOR FOG
DEVELOPMENT THAN KMCK...AND MODELS PLACE LOWER VISIBILITY CLOSER
TO KGLD THAN KMCK. DUE TO THE MOIST ENVIRONMENT AND RECENT
RAINFALL NEAR KMCK...WILL HAVE A SLIGHT REDUCTION IN VISIBILITY
FORECAST. WAS NOT CONFIDENT ENOUGH THAT FOG WOULD BE THICK ENOUGH
FOR MVFR TO PLACE A MENTION IN THE KMCK TAF...ALTHOUGH WOULD NOT
BE SURPRISED IF IT DID DROP TO THAT CATEGORY BRIEFLY. OTHERWISE
THE LIGHT AND VARIABLE WINDS WILL STRENGTHEN LATE MORNING THEN
TURN TO THE NORTH-NORTHEAST DURING THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...MK
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1132 PM MDT WED SEP 23 2015
.UPDATE...
ISSUED AT 850 PM MDT WED SEP 23 2015
REMOVED ANY MENTION OF RAINFALL FROM THE FORECAST UNTIL TOMORROW
AFTERNOON WHEN A BAND OF MOISTURE AND LIFT FROM THE UPPER LEVEL
TROUGH OVER NEBRASKA ROTATE SOUTH OVER GRAHAM AND NORTON COUNTIES.
BETWEEN NOW AND THEN THE ENVIRONMENT WILL BE VERY DRY AND LITTLE
TO NO LIFT. ANY STORMS WHICH DEVELOP SHOULD DO SO JUST EAST OF THE
AREA WHERE THE ENVIRONMENTAL MOISTURE WILL BE BETTER.
ADJUSTED THE PLACEMENT OF THE THICKEST FOG FOR TONIGHT TO MORE
OVER THE WESTERN HALF OR SO OF THE AREA. WOULD NOT BE SURPRISED TO
SEE FOG DEVELOP OVER THE NORTHEAST PART OF THE AREA WHERE THERE
WERE SCATTERED SHOWERS EARLIER THIS EVENING...AS WELL AS OVER THE
SOUTHWEST PART OF THE AREA. MODELS SEEM TO LOOSELY AGREE THE
DENSEST FOG WILL BE WEST OF HIGHWAY 25 AND NORTH OF I-70 WHERE THE
NORTHERLY WINDS WILL BE BRINGING IN MID 50S DEW POINTS FROM
WESTERN NEBRASKA ALONG WITH COOLER AIR. VISIBILITIES AROUND A MILE
OR TWO CAN BE EXPECTED AROUND SUNRISE FOR THIS PART OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 226 PM MDT WED SEP 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CLOSED UPPER LOW MOVING INTO NORTHCENTRAL NEBRASKA...WITH TROUGH
AXIS EXTENDING SOUTH ACROSS OUR CWA INTO SOUTHEAST COLORADO. STRONG
PV HEIGHT ANOMALY IS OVER OUR CWA ASSOCIATED WITH SW QUADRANT OF
CLOSED LOW. CONVERGENCE ALONG SURFACE TROUGH AXIS CURRENTLY SOUTH OF
I-70 AND MID LEVEL ROTATION ALONG SOUTHERN EDGE OF TROUGH HAS AIDED
IN THUNDERSTORM INITIATION ALONG AXIS OF STEEP LAPSE RATES/MODERATE
CAPE.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY WILL CONTINUE TO BE
POSSIBLE ALONG SURFACE TROUGH THIS ACTIVITY...POSSIBLY DEVELOPING
INTO NW KANSAS. HI RES GUIDANCE SHOWS THIS ACTIVITY REMAINING
ROUGHLY ALONG AND SOUTH OF I-70 ALONG TROUGH AXIS. TREND SHOULD BE
FOR THIS ACTIVITY TO TRANSITION TO THE SOUTH AS TROUGH AXIS SLIDES
SOUTH AND LOW LEVEL STABILIZE OVER OUR CWA. SHOWERS/ISOLATED
THUNDERSTORMS IN THE EASTERN CWA MAY CONTINUE TO LINGER THOUGH THE
NIGHT AS MOISTURE/MID LEVEL ENERGY CONTINUES TO ROTATE AROUND THE
MID LEVEL CLOSED LOW IN NEBRASKA. CAPE AXIS OF ROUGHLY 2000 J/KG
WILL SUPPORT SOME STRONGER UPDRAFTS WITH MARGINAL HAIL/WIND THREAT.
SHEAR IS UNIMPRESSIVE WITH EFFECTIVE SHEER BELOW 20KT...SO SEVERE
THREAT IS LIMITED THIS AFTERNOON AND EVENING.
OTHER CONCERN FOR TONIGHT WILL BE POTENTIAL FOR FOG DEVELOPMENT
AS SURFACE HIGH PRESSURE BUILDS IN TO THE WESTERN PART OF OUR CWA
AND SURFACE LOW SHIFTS EAST. WINDS WILL DECREASE BETWEEN THESE
FEATURES AND WITH CLEARING SKIES COMBINE WITH ABUNDANT LOW LEVEL
MOISTURE TO FOR FOG DEVELOPMENT ACROSS AT LEAST THE WESTERN PARTS
OF OUR CWA. CONFIDENCE IN A DENSE FOG EVENT IS LOWERED BY SHIFT IN
WINDS TO THE NW AROUND 12Z...WHICH COULD BRING DRIER AIR AND
BETTER BL MIXING. IN ANY CASE WITH SIGNAL DEPICTED BY SREF
PROBABILITIES AND NAM/RAP CONFIDENCE WAS HIGH ENOUGH TO ADD
PATCHY/AREAS MENTION TO MOST OF CWA.
THURSDAY...AS CLOSED LOW MEANDERS EASTWARD AND MEAN TROUGH AXIS
SHIFTS SOUTHEAST SUBSIDENCE AND A DEEP DRY MID LEVEL AIR MASS
WILL OVERSPREAD OUR CWA. BY LATE THURSDAY AFTERNOON A LOBE OF
VORTICITY MAY ROTATE AROUND BACK EDGE OF CLOSED LOW INTO OUR
CWA. CONSIDERING THE DRY NATURE OF THE AIR MASS...CONFIDENCE IN
MEASURABLE PRECIP WAS TOO LOW TO INCLUDE MENTION THURSDAY
AFTERNOON DESPITE SOME FORCING ALOFT AND STEEP LAPSE RATES. THERE
IS A SPLIT BETWEEN GUIDANCE REGARDING TEMPS AS SOME GUIDANCE SHOWS
REINFORCING CAA BEHIND UPPER LOW OVERSPREADING OUR CWA...WHILE
OTHER GUIDANCE SUPPORTS WAA AND HIGH PRESSURE BEGINNING TO BREAK
DOWN FROM THE WEST. I BUMPED UP TEMPS IN THE WEST (EASTERN
COLORADO) TO THE MID 80S...WITH HIGHS ELSEWHERE GENERALLY IN THE
UPPER 70S/NEAR 80F. THIS ISN`T FAR FROM MOST CONSENSUS SOLUTIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 205 PM MDT WED SEP 23 2015
FORECAST PROBLEMS WILL BE LINGERING CHANCES OF PRECIPITATION INTO
FRIDAY...STRATUS/FOG THURSDAY NIGHT/FRIDAY...AND HOW MUCH DO
TEMPERATURES RECOVER. SATELLITE IS SHOWING AN AMPLIFIED PATTERN OVER
THE PACIFIC WHICH THEN TRANSLATES TO A DEVELOPING TROUGH OVER THE
WESTERN PORTION OF THE COUNTRY THEN A RIDGE BEING PUSHED INTO THE
EASTERN PORTION OF THE COUNTRY.
AT JET LEVEL...THE GFS/CANADIAN/NAM STARTED OUT BEST. AT MID
LEVELS...THE GFS/UKMET/ECMWF WERE DOING A LITTLE BETTER THAN THE
CANADIAN/NAM. THE SREF WAS DOING A LITTLE BETTER THAN THE ECMWF ON
THE SURFACE WIND AND PRESSURE FIELD. THE GFS/SREF/CANADIAN WERE
DOING THE BEST ON THE LOW LEVEL THERMAL FIELD.
THURSDAY NIGHT...MODELS VERY SIMILAR TO 24 HOURS AGO. 70H LOW MOVES
TOWARD THE WEST THROUGH THE NIGHT AND IS JUST TO THE EAST/NORTHEAST
OF THE AREA. THE ECMWF IS FURTHER NORTH THAN IT WAS PREVIOUSLY.
NEGATIVE THETA-E LAPSE RATES ARE IN PLACE WITH NOT A LOT BUT
ADEQUATE MID LEVEL MOISTURE. AT THE SAME TIME AS THE LOW MOVES
CLOSER...A SHORTWAVE AND MID LEVEL FRONTOGENESIS ROTATES THROUGH
THE EASTERN THIRD OF THE AREA. MODELS ARE STILL PRODUCING SOME
VERY LIGHT QPF. THINK THERE WILL BE SOME RAINFALL BUT WITH VERY
LIGHT AMOUNTS.
MODELS HAVE ALSO BEEN CONSISTENT FROM YESTERDAY IN BRINGING/INCREASING
LOWER LEVEL MOISTURE ACROSS THE ENTIRE AREA IN THE LAST HALF OF
THE NIGHT. SO HAVE INCREASED CLOUD COVER AND INTRODUCED FOG. IT IS
POSSIBLE THAT COVERAGE COULD BE GREATER WITH DENSE FOG INDICATED.
FRIDAY/FRIDAY NIGHT...EVEN THOUGH 70H LOW WEAKENS...IT CONTINUES
TO DROP SOUTH AND WEST INTO THE FORECAST AREA THROUGH THE DAY. AGAIN
MODELS NOT SHOWING A LOT OF MOISTURE. HOWEVER MODELS...ESPECIALLY
THE ECMWF...IS INDICATING A RATHER STRONG SHORTWAVE TROUGH ROTATING
THROUGH THE AREA. ONCE AGAIN THERE WILL BE NEGATIVE THETA-E LAPSE
RATES IN PLACE ALONG WITH SOME CAPE AROUND. TQ INDEX ALSO INDICATES
INSTABILITY SHOWERS/THUNDERSTORMS POSSIBLE.
LIGHT QPF SHOWN BY OUTPUT AS WELL AS WPC WHICH MATCHES THE ABOVE
REASONING. IT IS POSSIBLE THAT IT COULD END UP BEING SPRINKLES BUT
BELIEVE THERE WILL BE SOME KIND OF SHOWER ACTIVITY AROUND THROUGH
THE AFTERNOON. SO PUT IN A SLIGHT CHANCE OF PRECIPITATION FOR THE
AFTERNOON. MODELS SHOW THE STRATUS AND FOG BURNING OFF BY LATE
MORNING. AM A LITTLE BIT CONCERNED WITH THAT SINCE THE WIND FIELD
WILL REMAIN LIGHT AND SHIFT TO A MORE EASTERLY DIRECTION AS THE DAY
PROGRESSES. WILL END FOG BY MID MORNING BUT STRATUS MAY HOLD ON
LONGER. BECAUSE OF THE CLOUD COVER AND UNFAVORABLE WINDS LOWERED THE
HIGH TEMPERATURES A LITTLE.
AIR MASS LOOKS LIKE IT STABILIZES RAPIDLY LATE IN THE AFTERNOON WITH
THE MAIN LIFT HAVING ALREADY MOVED THROUGH THE AREA. SO FOR NOW
WILL LEAVE THE NIGHTTIME PERIOD DRY WITH HIGH SILENT POPS. IT IS
POSSIBLE THAT SOMETHING COULD BE ONGOING AT THE BEGINNING BUT IT
SHOULD END QUICKLY. RETURN FLOW BEGINS DURING THE NIGHT WITH A
LITTLE MORE WIND EXPECTED WITH THE EAST SEEING THE LEAST AMOUNT.
MODELS NOT AS HIGH WITH THE LOW LEVEL MOISTURE SO WILL LEAVE OUT
ANY MENTION OF FOG FOR NOW.
SATURDAY...RIDGE BUILDS INTO THE AREA WITH INCREASING SOUTHERLY
WINDS AND WARM AIR ADVECTION. THINK SOME OF THE GUIDANCE IS TOO WARM
DUE TO A LACK OF DOWNSLOPE COMPONENT TO THE WIND AND THAT THE FLOW
ALOFT WILL STILL BE OUT OF THE NORTH. ADJUSTED THE MAX TEMPERATURES
DOWN SLIGHTLY...ESPECIALLY FOR THE CENTRAL AND EASTERN PORTIONS.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS STILL SHOWING A LOT OF
DISAGREEMENT IN HOW TO HANDLE THE EASTERN PACIFIC TROUGH AND
WESTERN/CENTRAL RIDGE. THE ECMWF AND CANADIAN ARE STILL THE FURTHEST
WEST AND MORE CUTOFF WITH THE GFS STILL PUSHING THE TROUGH FURTHER
TO THE EAST WHILE RETAINING THE CUTOFF. ALTHOUGH THE GFS IS SLOWER
TODAY THAN YESTERDAY. CONSIDERING THE FLOW PATTERN...CONSISTENT
ECMWF/CANADIAN AND THE SLOWER GFS...THE MORE AMPLIFIED AND SLOWER
SOLUTION LOOKS THE BEST. THE WPC MANUAL PROGS ECHO THIS AS WELL.
SAYING THAT IT LOOKS LIKE DRY AND WARMER WEATHER WILL BE THE
PREVAILING CONDITIONS FOR THIS PERIOD AND LEFT WHAT THE CRH_INIT
GAVE ME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1127 PM MDT WED SEP 23 2015
VFR TO MVFR CONDITIONS FORECAST FOR THE 6Z TAFS. MAIN ISSUE WILL
BE HOW LOW VISIBILITIES WILL FALL AROUND SUNRISE DUE TO THE MOIST
LOW LEVELS. SOUNDINGS FOR KGLD ARE MORE FAVORABLE FOR FOG
DEVELOPMENT THAN KMCK...AND MODELS PLACE LOWER VISIBILITY CLOSER
TO KGLD THAN KMCK. DUE TO THE MOIST ENVIRONMENT AND RECENT
RAINFALL NEAR KMCK...WILL HAVE A SLIGHT REDUCTION IN VISIBILITY
FORECAST. WAS NOT CONFIDENT ENOUGH THAT FOG WOULD BE THICK ENOUGH
FOR MVFR TO PLACE A MENTION IN THE KMCK TAF...ALTHOUGH WOULD NOT
BE SURPRISED IF IT DID DROP TO THAT CATEGORY BRIEFLY. OTHERWISE
THE LIGHT AND VARIABLE WINDS WILL STRENGTHEN LATE MORNING THEN
TURN TO THE NORTH-NORTHEAST DURING THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS DULUTH MN
109 AM CDT THU SEP 24 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 357 PM CDT WED SEP 23 2015
RAIN CONTINUES INTO THE NIGHT WITH DREARY CONDITIONS PERSISTING INTO
TOMORROW. TEMPERATURES HAVE BEEN COOL TODAY ESPECIALLY ALONG THE
LAKE SUPERIOR COASTLINE WHERE WINDS HAVE BEEN STRONG OFF THE
LAKE...GUSTING TO 25 TO 35 MPH AT TIMES. WARMER TOMORROW...BUT SKIES
REMAIN MOSTLY CLOUDY.
FORECAST WORKED OUT FAIRLY WELL TODAY WITH THE AXIS OF HEAVIEST
PRECIP ABOUT WHERE WE WERE EXPECTING IT. THE FIRST ROUND OF STORMS
TAPERED OFF FASTER THAN ANTICIPATED THIS AFTERNOON...BUT ADDITIONAL
DEVELOPMENT IS ALREADY ONGOING AND ANOTHER WAVE OF WIDESPREAD
RAINFALL IS EXPECTED LATE TONIGHT. WHILE FLASH FLOOD THREAT IS
FAIRLY LOW DUE TO STORM MOTION...SOME URBAN AND SMALL STREAM
FLOODING IS POSSIBLE WITH ANY STORM TONIGHT DUE TO THE EXTREMELY
MOIST NATURE OF THE ATMOSPHERE. PRECIPITABLE WATER VALUES OF 1.0 TO
1.4 ALREADY EXIST ACROSS THE AREA PER RAP/MESOANALYSIS AND EVEN
HIGHER PWATS ARE ABOUT TO BE ADVECTED INTO NORTHWEST WISCONSIN THIS
EVENING AS THE UPPER LOW/SHORTWAVE OVER THE MID MISSOURI VALLEY
GRADUALLY DRIFTS EASTWARD. CURRENT RAP INDICATES PWATS WILL RISE TO
1.4 TO 1.6 INCHES OR HIGHER FROM THE TWIN PORTS AND INTERSTATE 35
CORRIDOR EAST ACROSS PARTS OF NORTHWEST WISCONSIN. THE SOUTH SHORE
OF WISCONSIN IS ESPECIALLY PRIMED FOR POTENTIAL FLOODING AFTER HEAVY
RAINFALL THIS AFTERNOON BROUGHT AROUND TWO INCHES TO MUCH OF
NORTHERN DOUGLAS AND BAYFIELD COUNTIES. WHILE MOST OF THIS RAINFALL
SIMPLY RUNS OFF INTO LAKE SUPERIOR...SATURATED GROUNDS COULD LEAD TO
MINOR FLOODING TONIGHT. WINDS WILL GRADUALLY WEAKEN TONIGHT...BUT
REMAIN GUSTY AT TIMES ALONG THE LAKE SUPERIOR SHORELINE. SOME
PATCHY FOG POSSIBLY ESPECIALLY IN THE BRAINERD LAKES TO LEECH LAKE
AREA WHERE LIGHTER WINDS ARE EXPECTED.
FOR THURSDAY THINGS WILL WIND DOWN AS THE UPPER LOW/SHORTWAVE
DISSIPATES AND A RIDGE BUILDS OVER THE FOUR CORNERS REGION INTO THE
CENTRAL/NORTHERN PLAINS. THE WEAK WARM FRONT CURRENTLY ACROSS
NORTHWEST WISCONSIN WILL GRADUALLY DRIFT SOUTHWARD AND
DISSIPATE...THOUGH LOW LEVEL MOISTURE IS EXPECTED TO REMAIN IN PLACE
THROUGH THE DAY RESULTING IN MOSTLY CLOUDY SKIES. A WEAK SHORTWAVE
TROUGH WILL MOVE ACROSS SOUTHERN MANITOBA INTO NORTHWEST ONTARIO
WHICH COULD RESULT IN A FEW SHOWERS IN NORTHEAST MINNESOTA...AND
WITH THE MOISTURE ALREADY IN PLACE IT MAY NOT TAKE MUCH LIFT TO GET
RAIN/DRIZZLE GOING. TEMPS A LITTLE WARMER DUE TO WARM AIR ADVECTION
TAKING PLACE THROUGH THE DAY...HIGHS IN THE UPPER 50S TO LOW 60S
ACROSS THE MN ARROWHEAD TO MID 60S TO NEAR 70 ELSEWHERE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM CDT WED SEP 23 2015
WEAK UPPER RIDGING BUILDING IN THURSDAY NIGHT INTO FRIDAY WILL BRING
MAINLY DRY CONDITIONS FOR MOST AREAS OF THE NORTHLAND. THERE MAY BE
SOME SHOWERS THAT LINGER OVER FAR NORTHERN MINNESOTA INTO FRIDAY
MORNING. CLOUDS WILL BE SLOW TO DISSIPATE FRIDAY AND WE INCREASED
THEM AND THEY MAY HAVE TO BE INCREASED FURTHER AS SOME OF THE MODELS
ARE SHOWING LOW LEVEL MOISTURE SLOW TO DEPART. HIGHS SHOULD BE FROM
THE UPPER SIXTIES TO LOWER SEVENTIES.
THE NORTHLAND WILL BE BETWEEN DEPARTING HIGH PRESSURE TO THE EAST
AND A COLD FRONT WELL WEST ON SATURDAY. THIS WILL CREATE A WARM
SOUTHERLY FLOW WITH HIGHS IN THE MID TO UPPER SEVENTIES.
THE UPPER FLOW WILL BECOME INCREASINGLY MORE WESTERLY THROUGH THE
WEEKEND INTO EARLY NEXT WEEK PUSHING THE COLD FRONT THROUGH THE
REGION AND SENDING SEVERAL SHORTWAVES THROUGH AS WELL. WE HAVE
CHANCES FOR SHOWERS/STORMS SUNDAY INTO TUESDAY. TEMPERATURES SUNDAY
WILL STILL BE IN THE SEVENTIES THEN FALL INTO THE SIXTIES TUESDAY
AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 109 AM CDT THU SEP 24 2015
EXPECTING IFR/LIFR CIGS AT ALL TERMINALS EXCEPT FOR KHYR. CIGS
WILL LOWER AS PRECIPITATION MOVES THROUGH...HOWEVER UPSTREAM OBS
SITES ARE REPORTING MVFR/VFR CIGS. NOT CONFIDENT THAT IFR CIGS ARE
OUT OF THE QUESTION...AS THE GFS MOS HINTS AT THIS POSSIBILITY
ALONG WITH SURROUNDING SITES SHOWING IFR CIGS. LIFR VISBY IS
EXPECTED FROM TIME TO TIME AT KBRD AND KDLH BETWEEN 08-13Z. LATEST
GFS/NAM MOS GUIDANCE CONTINUES TO SHOW LOW VISBY DURING THIS TIME
FRAME...BUT THINK WINDS WILL BE HIGH ENOUGH TO KEEP FROM
PREVAILING. OTHER SITES WILL ALSO SEE LOWER VISBY...BUT REMAIN IN
THE IFR/MVFR RANGE.
PRECIPITATION WILL COME TO AN END BETWEEN 14Z AND 21Z...PER THE
LATEST HRRR/RAP/NAM GUIDANCE. KHYR...KBRD AND KINL WILL SEE CIGS
AND VISBY IMPROVE TO MVFR/VFR BY THE END OF THE FORECAST. STAYED
PESSIMISTIC AT KDLH AND KHIB WITH IFR CIGS AS ALL THE LATEST
GUIDANCE SHOWS THIS. HINTED AT FOG FORMATION AT KDLH AND KHIB
TOWARDS THE END OF THE CURRENT TAF CYCLE...AS WINDS BECOME LIGHT
AND DUE TO THE RECENT PRECIPITATION.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 53 69 53 74 / 10 10 0 0
INL 51 71 54 76 / 20 20 0 0
BRD 54 74 56 77 / 10 10 0 0
HYR 51 74 52 74 / 10 10 0 0
ASX 51 70 53 75 / 10 10 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR
LSZ140>147.
&&
$$
SHORT TERM...JJM
LONG TERM...MELDE
AVIATION...WL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1244 AM EDT THU SEP 24 2015
.SYNOPSIS...
BROAD HIGH PRESSURE WILL EXTEND OVER THE AREA FROM THE NORTH
THROUGH THE WEEKEND. LOW PRESSURE OFFSHORE TO THE SOUTHEAST
WILL MOVE SOUTHWEST THROUGH THURSDAY...AND THEN WEST FRIDAY.
LOW PRESSURE WILL MOVE NORTHEAST OVER THE AREA THIS WEEKEND AND
AWAY FROM THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1230 AM THURSDAY...UPDATED TO ISSUE COASTAL FLOOD ADVSY FOR
OB DARE...AND FOR AREAS ADJACENT TO SRN PAMLICO SOUND AND NEUSE
RIVER. SEE COASTAL FLOODING SECTION BELOW FOR DETAILS.
ALSO UPDATED TO INCREASE POPS TO LIKELY SRN OBX AND SRN COASTAL
SECTIONS REST OF NIGHT...BASED ON LATEST RADAR TRENDS AND MESO
MODELS. NO OTHER SIGNIFICANT CHANGES.
/PREVIOUS DISCUSSION/
AS OF 1030 PM WEDNESDAY...NO SIG CHANGE TO THE UPDATE. HAVE NOTED
A BIT MORE DRIZZLE THAN RAIN SHOWERS THIS EVENING AS MOISTURE
CONTINUES TO STREAM INTO THE IMMEDIATE COAST. SO HAVE ADJUSTED WX
TO REFLECT THIS. APART FROM THIS COSMETIC ISSUE...THE FORECAST IS
ON TRACK FOR A BREEZY...CLOUDY AND DRIZZLY NIGHT ALONG OUR COAST.
PREVIOUS DISCUSSION...NO REAL CHANGE TO THE WEATHER PATTERN THAT
HAS GRIPPED THE REGION THIS WEEK. HIGH PRESSURE RIDGING SOUTH INTO
THE CAROLINAS IS PRODUCING A DAMMING/WEDGE SURFACE PATTERN WHILE A
WEAK/BROAD AREA OF LOW PRESSURE OFFSHORE IS SLOWLY RETROGRESSING
TOWARD THE SOUTHEAST COAST. AS BEEN THE THE CASE THE PAST SEVERAL
DAYS THE MOST DIFFICULT PORTION OF THE FORECAST CONCERNS
DETERMINING THE LOCATION, TIMING, AND AMOUNTS OF PRECIPITATION.
THE MODELS HAVE BEEN TOO AGGRESSIVE THE PAST 3 DAYS IN FORECASTING
PRECIPITATION ACROSS EASTERN NC. THUS WILL DECREASE POPS FOR THE
EVENING HOURS TO 20-30% AS RADAR INDICATES WHAT LITTLE
PRECIPITATION THERE IS WAS LOCATED MAINLY OFFSHORE. WILL MAINTAIN
CURRENT 30-50% POPS AFTER MIDNIGHT AND CONTINUE TO MONITOR
PRECIPITATION TRENDS BUT THESE MAY BE OVERDONE AND MAY NEED TO BE
DECREASED WITH THE 10 PM UPDATE. L0W TEMPERATURES OVERNIGHT WILL
RANGE FROM THE MID 60S FAR WEST TO LOWER 70S COAST WITH OVERCAST
SKIES AND GUSTY NORTHEAST WINDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
AS OF 315 PM WEDNESDAY...GOOD AGREEMENT AMONGST THE GFS/NAM12 AND
ECMWF REGARDING HIGH LIKELIHOOD OF PRECIPITATION TOMORROW AS
SURFACE LOW AS SURFACE LOW MOVES WEST AND MID/UPPER LEVEL LOW
SLOWLY PULLS NORTHEAST FROM THE CENTRAL GULF COAST. GOOD MOISTURE
FLUX AND ISENTROPIC LIFT SHOULD LEAD TO WIDESPREAD LIGHT TO
MODERATE RAIN ACROSS THE REGION...PRIMARILY IN THE AFTERNOON HOURS
THURSDAY. CLOUD COVER AND PRECIPITATION WILL HOLD MAXIMUM
TEMPERATURES GENERALLY IN THE MID/UPPER 70S. RAINFALL AMOUNTS
SHOULD AVERAGE ONE QUARTER TO ONE HALF INCH.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM WED...A COMPLEX FORECAST CONTINUES ACROSS EASTERN NC
BRINGING WET AND BREEZY TO WINDY CONDITIONS THROUGH MUCH OF THE
WEEKEND.
THURSDAY NIGHT...MDLS SHOW OFFSHORE CSTL TRF BECOMING LESS
DEFINED AND SHIFTING TOWARD THE COAST. PLENTY OF MOISTURE WILL
CONT TO STREAM ACRS THE REGION WITH PRECIP WTR VALUES NEAR 2
INCHES. WILL HAVE LIKELY POPS ALL AREAS AS MDLS SHOW GOOD QPF OVER
THE REGION WITH INCREASED UPPER LEVEL DIFFLUENCE. CLOUDS AND
PRECIP WILL KEEP TEMPS MILD WITH LOWS IN THE MID TO UPPER 60S
INLAND AND LOWER 70S BEACHES.
FRIDAY THROUGH SUNDAY...NUMEROUS SHOWER...SOME HEAVY EXPECTED INTO
SUNDAY AS DEEP MOISTURE PERSISTS OVER THE REGION WITH SFC TRF IN
THE AREA AND WEAK DIFL ALOFT. CONT LIKELY POPS THRU SAT NIGHT AND
SEVERAL INCHES OF RAINFALL WILL BE POSS IN SPOTS ESPCLY COAST.
SOME DIFF IN MDLS CONT LATER IN WEEKEND WITH GFS QUICKER TO LIFT
SFC LOW AND DEEPER MOISTURE N OF THE REGION SUNDAY. FOR NOW CONT
PREV FCST WITH CHC POPS SUNDAY GIVEN UNCERTAINTY. WIDESPREAD
CLOUDS AND PRECIP WILL KEEP TEMPS STEADY THRU SUNDAY WITH MILD
LOWS IN 60S TO LOWER 70S WITH HIGHS MOSTLY IN THE 75 TO 80 DGR
RANGE.
MONDAY THRU WED...LOW PRES PROGGED TO MOVE NE OF THE AREA EARLY
NEXT WEEK WITH A DRYING TREND AS THE DEEP MOISTURE LIFTS NORTH OF
THE AREA AND HIGH PRES BUILDS IN FROM THE WEST. TEMPS WARM
SLIGHTLY WITH GREATER INSOLATION EXPECTED AND EXPECT HIGHS IN THE
LOWER 80S.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 00Z THURSDAY/...
AS OF 630 PM WEDNESDAY...EXPECTING VARIABILITY AT THE INLAND
(ISO/PGV) TAF SITES THIS EVENING FROM MVFR TO VFR CEILINGS WHILE
MVFR CEILINGS PERSIST AT OAJ AND EWN. LATER TONIGHT THE MODELS
INDICATE THAT THE LOW LEVEL FLOW WILL VEER FROM NORTHEAST TO EAST
AND MOISTEN THE LOW LEVELS. MOIST OF THE NUMERICAL AVIATION
GUIDANCE IS INDICATING IFR CEILINGS DEVELOPING LATE TONIGHT (AFTER
06Z) WHILE THE NARRE AND HRRR GUIDANCE ARE AT ODDS WITH THIS. DUE
TO THIS UNCERTAINTY WILL MAINTAIN A MVFR CEILING FORECAST AND
CONTINUE TO MONITOR. ON THURSDAY WE ARE EXPECTING MORE WIDESPREAD
SHOWER ACTIVITY AND EXPECT A CONTINUATION OF MVFR CEILINGS.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM WED...POOR FLYING THRU MUCH OF THE WEEKEND. DEEP
MOISTURE OVER THE AREA WITH LEAD TO BOUTS OF SHRA WITH PROLONGED
PDS PERIODS OF SUB VFR CONDITIONS LIKELY...WITH SOME IFR
EXPECTED. MOISTURE BEGINS TO DIMINISH LATER SUN AND ESPCLY MON
WITH LESS SHRA AND PROB MORE VFR.
&&
.MARINE...
SHORT TERM /THROUGH THU/...
AS OF 1230 AM THURSDAY...RAISED POPS TO LIKELY OVER SRN AND
CENTRAL WATERS REST OF NIGHT...NO OTHER SIGNIFICANT CHANGES.
/PREVIOUS DISCUSSION/
AS OF 1030 PM WEDNESDAY...NO SIG CHANGES TO THE UPDATE WITH STRONG
NE FLOW CONTINUING ACROSS THE WATERS. WINDS 20-25KTS GUSTING
AROUND 30KTS. SEAS 6-11 FT.
PREVIOUS DISCUSSION...GUSTY N/NE WINDS AND ROUGH SEAS WILL
PERSIST THROUGH THURSDAY WITH LOW PRESSURE OFFSHORE AND STRONG
HIGH PRESSURE LOCKED OVER THE NORTHEAST. THE LOW SHOULD SLOWLY
START TO DRIFT TOWARD THE SOUTHEAST COAST LATE TONIGHT DECREASING
THE GRADIENT AND WINDS SHOULD DIMINISH A BIT INTO THURSDAY...BUT
PER LOCAL SWAN/NWPS...SEAS SHOULD REMAIN ELEVATED.
CURRENTLY...WINDS ARE GUSTING TO AROUND 30 KNOTS WITH SEAS 6 TO 10
FEET. AS WITH THE WINDS...SEAS WILL SUSBIDE A BIT ON THURSDAY BUT
SHOULD STILL REMAIN IN THE 6 TO 8 FOOT RANGE AT MOST LOCATIONS.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM WED...HIGH CONFIDENCE IN POOR BOATING CONDITIONS FOR
MUCH OF THE LONG TERM AS PERSISTENT MODERATE TO OCNLY STRONG NE/E
WINDS AND ROUGH SEAS WILL DOMINATE. THE TWO MAIN FEATURES ARE
PERSISTENT HIGH PRESSURE THAT WILL BE ANCHORED TO THE NORTH AND AN
ELONGATED AREA OF LOW PRESSURE OFF THE SE COAST THAT WILL PRODUCE
A TIGHT PRESSURE GRADIENT. THE LOW WILL MOVE ONSHORE TO THE SOUTH
OF ENC ON THURSDAY INTO FRIDAY, WITH WINDS 15-25KT WITH SEAS 4-8
FT HIGHEST NORTH.
MODELS ARE STILL NOT IN THE BEST AGREEMENT WITH THE NEXT SYSTEM
THIS WEEKEND. GFS QUICKLY LIFTS LOW OVER AND N OF REGION SUNDAY
WHILE ECMWF KEEPS IT TO THE S THRU SUNDAY WHICH LEADS TO LONGER
PERIOD OF STRONGER ONSHORE WINDS. CONT PREV FCST WITH MODERATE
ONSHORE FLOW CONT INTO SUNDAY. SEAS EXPECTED TO BUILD TO 8 TO 11
FT CNTRL AND N AND 4 TO 6 FEET S THRU THE WEEKEND.
MDLS DIFFER A BIT WITH WIND DIR EARLY NEXT WEEK BUT AGREE ON
DIMINISHING WINDS...MAINLY FROM A NRLY DIR. AS WINDS DIMINISH
SEAS WILL SUBSIDE TO 4 TO 6 FT N AND 3 TO 5 FT S LATER MON.
&&
.TIDES/COASTAL FLOODING...
AS OF 1230 AM THURSDAY...POSTED COASTAL FLOOD ADVISORY UNTIL 6 PM
TODAY FOR OBX N OF HAT...AND CARTERET/CRAVEN/PAMLICO COUNTIES
ADJACENT TO SRN PAMLICO SOUND AND NEUSE RIVER. REPORT FROM
CLUBFOOT CREEK IN CRAVEN COUNTY OF WATER LEVEL 3 FT ABOVE
NORMAL...AND ALSO SOME OVERWASH NEAR BUXTON. WINDS EXPECTED TO
DIMINISH OVERNIGHT AND THURSDAY...BUT PERSISTENT NE FETCH WILL
LIKELY KEEP WATER LEVELS ELEVATED THROUGH THIS AFTN.
/PREVIOUS DISCUSSION/
AS OF 325 PM WEDNESDAY...THE HIGH SURF ADVISORY HAS BEEN EXTENDED
THROUGH THURSDAY AFTERNOON. PERSISTENT NORTHEAST WINDS WILL
CONTINUE TO PRODUCE 6 TO 9 FOOT SURF ALONG WITH A HIGH THREAT OF
RIP CURRENTS AND POSSIBLE BEACH EROSION.
UNCERTAINTY CONTINUES THIS WEEKEND...BUT ROUGH SEAS AND STRONG NE
WINDS ARE POSSIBLE...ESPECIALLY SATURDAY. IN ADDITION TO THE
OCEANSIDE IMPACTS, SOUNDSIDE LOCATIONS VULNERABLE TO STRONG NE
WINDS COULD SEE MINOR WATER LEVEL RISES, WHICH WOULD BE
EXACERBATED BY THE HIGH ASTRONOMICAL TIDES THIS WEEKEND INTO EARLY
NEXT WEEK. STAY TUNED TO LATER FORECASTS AS HOPEFULLY CONFIDENCE
INCREASES.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 6 PM EDT THIS EVENING FOR NCZ103.
COASTAL FLOOD ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
NCZ093>095-103.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT EARLY THIS MORNING FOR
AMZ130-131-135.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR AMZ150-152-154.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR AMZ156-
158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...JME/CTC/LEP/JBM
SHORT TERM...CTC
LONG TERM...RF
AVIATION...RF/JME
MARINE...RF/JME/CTC/LEP/JBM
TIDES/COASTAL FLOODING...CTC/JBM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
321 AM CDT THU SEP 24 2015
.UPDATE...
ISSUED AT 319 AM CDT THU SEP 24 2015
A DENSE FOG ADVISORY WILL BE ISSUED FOR PORTIONS OF SOUTH CENTRAL
NORTH DAKOTA INCLUDING THE JAMES RIVER VALLEY. WEBCAMS AND SURFACE
OBSERVATIONS SUPPORT AN ADVISORY AND THE HRRR VISIBILITY FORECAST
MAINTAINS LESS THAN ONE HALF MILE THROUGH THE MORNING. THIS
ADVISORY MAY NEED TO BE EXTENDED WEST AND NORTH AT SOME POINT
LATER THIS MORNING. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 149 AM CDT THU SEP 24 2015
LATEST WATER VAPOR IMAGERY SHOWS A DISTINCT SHORTWAVE NEAR
SHERWOOD MOVING EAST WITH TIME. A CONTINUOUS BAND OF SHOWERS AND
THUNDERSTORMS HAS PROMPTED THE ISSUANCE OF A FEW AREAL FLOOD
ADVISORIES ACROSS NORTH CENTRAL NORTH DAKOTA THROUGH 0600 AM CDT.
EXPECT THE PRECIPITATION AREA TO GRADUALLY SHIFT EAST AND EXIT
THE TURTLE MOUNTAINS BETWEEN 15Z-17Z THURSDAY.
OTHERWISE...STRATUS AND POTENTIALLY WIDESPREAD DENSE FOG TAKE
CONTROL OVER THE REST OF THE FORECAST AREA THROUGH THE MORNING
HOURS. THE RAP13/HRRR/NAM REMAIN PERSISTENT IN DEVELOPING LOW
VISIBILITIES/LESS THAN ONE HALF MILE...AND CLOUDS BETWEEN 200FT
AND 1000FT THROUGH 18Z THURSDAY. CLOUDS HAVE BEEN LOWERING HERE
AT BISMARCK...AS WELL AS OTHER SURROUNDING SURFACE OBSERVATIONAL
SITES WHICH FURTHER SUPPORT THE STRATUS AND FOG. MAY BE ISSUING A
DENSE FOG ADVISORY AT SOME POINT AFTER THIS DISCUSSION IS
DISSEMINATED. MID/UPPER LEVEL RIDGE BEGINS TO BUILD NORTHEAST
THURSDAY AFTERNOON AS HEIGHTS RISE FROM SOUTHWEST TO NORTHEAST.
DECREASING CLOUDS WITH AMPLE SUNSHINE RETURN DURING THE AFTERNOON
HOURS. HIGHS IN THE 70S TODAY WITH 80F IN THE FAR WEST.
ALTHOUGH DRYING AND WARMING CONDITIONS COMMENCE LATER TODAY...NAM
BUFKIT SOUNDINGS AND TO SOME EXTENT THE GFS SHOW A SHALLOW LAYER
OF LOW CLOUDS/FOG AGAIN DEVELOPING OVER SOUTH CENTRAL...KBIS/KJMS
AFTER MIDNIGHT THURSDAY INTO EARLY FRIDAY MORNING. THIS IS DUE TO
A WEAK BUT PERSISTENT LOW LEVEL EAST TO SOUTHEAST WIND.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 149 AM CDT THU SEP 24 2015
A WARM UP INTO SATURDAY FOLLOWED BY A COOL DOWN EARLY NEXT WEEK
HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD
AGREEMENT ON AN AMPLIFYING UPPER LEVEL RIDGE FROM THE SOUTHWEST US
INTO THE NORTHERN PLAINS THURSDAY INTO FRIDAY. THIS RIDGE IS
FORECAST TO BREAK DOWN BY SUNDAY...WITH A POTENTIAL BROAD UPPER
LEVEL TROUGH DEVELOPING ACROSS THE REGION EARLY NEXT WEEK.
THUS...TEMPERATURES ARE FORECAST TO WARM INTO SATURDAY...WITH
WIDESPREAD HIGHS IN THE 80S POSSIBLE SATURDAY AHEAD OF A STRONG
COLD FRONT FORECAST TO PROPAGATE ACROSS THE STATE SATURDAY NIGHT
INTO SUNDAY. THEREAFTER...A RETURN TO COOLER BUT STILL NEAR
NORMAL HIGHS IN THE 60S ARE EXPECTED NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY) ISSUED AT 149
AM CDT THU SEP 24 2015
MVFR CIGS/VSBYS FORECAST TO DETERIORATE TO IFR/LIFR AS WIDESPREAD STRATUS
AND FOG DEVELOP BY 12Z THURSDAY. THIS IS FORECAST TO BE MAINTAINED
UNTIL 18Z THURSDAY...WITH VFR CONDITIONS RETURNING THEREAFTER.
HOWEVER...KBIS/KJMS MAY RETURN BACK INTO MVFR STATUS AFTER 06Z
FRIDAY AS LIGHT SOUTHEAST WINDS CONTINUE TO BRING IN SHALLOW LOW
LEVEL MOISTURE. WINDS WILL REMAIN AT OR BELOW 10KT THROUGH THE
FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CDT /11 AM MDT/ TODAY FOR
NDZ034>037-042-045>048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...KS
LONG TERM...AYD
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1211 AM CDT THU SEP 24 2015
.UPDATE...
ISSUED AT 1211 AM CDT THU SEP 24 2015
WEST-EAST BAND OF SHOWERS AND THUNDERSTORMS ONGOING FROM NEAR
POWERS LAKE TO LANSFORD AND EAST TO ROLETTE. EXTENDED THE AREAL
FLOOD ADVISORY FOR ROLETTE COUNTY UNTIL 530AM CDT THURSDAY AS
ADDITIONAL SHOWERS/THUNDERSTORMS MARCH ACROSS THIS AREA REST OF
THE OVERNIGHT PERIOD. WE ALSO JUST ISSUED A NEW AREAL FLOOD
ADVISORY FOR NORTHEAST MOUNTRAIL/NORTHERN WARD/SOUTHERN
RENVILLE/AND SOUTHWEST BOTTINEAU COUNTIES AS CELLS CONTINUE TO
TRAIN OVER THE SAME AREA. THE OTHER ISSUE FOR THE REST OF
WEDNESDAY NIGHT IS CLOUDS AND FOG. THE HRRR/RAP13/NAM ALL SHOWING
WIDESPREAD IFR/LIFR CONDITIONS DEVELOPING WITH DENSE FOG.
ANTICIPATING THAT THIS WILL OCCUR GIVEN CONTINUED MOIST
EAST/SOUTHEAST FLOW AND SOME UPSTREAM OBSERVATIONS SUPPORTING THIS
POTENTIAL.
UPDATE ISSUED AT 948 PM CDT WED SEP 23 2015
MAIN UPDATE WAS TO ADJUST POPS FOR ONGOING CONVECTION OVER THE
NORTH CENTRAL...AND ANTICIPATED RE-DEVELOPMENT OF SHOWERS AND
ISOLATED THUNDERSTORMS ACROSS THE NORTH LATER TONIGHT. SOME
INDICATIONS OF THE SHOWERS CAN ALREADY BE SEEN OVER NORTHWEST
NORTH DAKOTA LATE THIS EVENING. LATEST TIME LAGGED HRRR BRINGS
ANOTHER ROUND OF SHOWERS AND POSSIBLE THUNDER INTO THE TURTLE
MOUNTAINS AREA AFTER MIDNIGHT FROM AROUND 7 TO 10 UTC. MAY NEED TO
EXTEND CURRENT AREAL FLOOD ADVISORY IF THIS PANS OUT...WITH
DOPPLER ESTIMATES OF UP TO 4 INCHES ACROSS ROLETTE COUNTY. ONLY
GROUND TRUTH RECEIVED SO FAR WERE 1 INCH SOUTH OF BELCOURT AND
1.58 INCHES IN BOTTINEAU. BOTH OF THESE WERE AWAY FROM THE HIGHEST
ESTIMATES.
ALSO ADDED PATCHY FOG ACROSS WESTERN AND CENTRAL NORTH DAKOTA. FOG
ALREADY SETTLING IN AT KJMS. SKIES REMAIN CLEAR IN THE SOUTHWEST
AND WITH MOISTURE TRANSPORT CONTINUING INTO THE AREA...EXPECT LOW
STRATUS AND/OR FOG WILL BE A GOOD BET HERE AS WELL. MOST ANY
LOCATION COULD SEE FOG LATE TONIGHT INTO THURSDAY MORNING.
UPDATE ISSUED AT 645 PM CDT WED SEP 23 2015
HAVE RAISED POPS ACROSS THE FAR NORTH CENTRAL THIS EVENING WITH
SHOWERS AND THUNDERSTORMS TRACKING EAST NORTHEAST FROM AROUND
SHERWOOD TO BOTTINEAU AND ROLLA. THIS ACTIVITY SHOULD MOVE OUT OF
THE AREA IN THE NEXT FEW HOURS. LATEST MESO-SCALE MODELS SHOW
ANOTHER AREA OF SHOWERS DEVELOPING LATER THIS EVENING OVER THE
WEST CENTRAL AND TRACKING MAINLY ACROSS THE NORTHERN HALF OF THE
CWA. WILL CONTINUE TO MONITOR BUT CURRENT POPS DO NOT REFLECT
THIS. WE DO HAVE SOME SLIGHT CHANCE TO CHANCE POPS REMAINING
ACROSS THE NORTH TONIGHT SO THINK THIS WILL SUFFICE UNLESS WE SEE
SHOWERS DEVELOPING AGAIN LATER THIS EVENING.
ADJUSTED SKY COVER AS WE HAVE CLEARED OUT OVER A GOOD PORTION OF
THE SOUTHWEST. MAIN QUESTION HERE IS WILL WE CLOUD BACK UP LATER
TONIGHT WITH LOW STRATUS. WITH LOW LEVEL MOISTURE REMAINING...HAVE
LEANED THIS WAY WITH THE 00Z TAF ISSUANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 258 PM CDT WED SEP 23 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER EASTERN COLORADO INTO
WESTERN NEBRASKA WITH HIGH OVER NORTHERN/CENTRAL MANITOBA INTO
ONTARIO. UPPER LEVEL ANALYSIS PLACES BROAD LOW OFF THE BC COAST
WITH SPLIT FLOW OVER OUR REGION AS COMPACT LOW LIFTS LIFTS FROM
NORTHERN NEBRASKA INTO SOUTHERN SOUTH DAKOTA. THIS IS RESULTING IN
A FEW LIGHT SHOWERS OVER FAR SOUTHEAST NORTH DAKOTA...WHILE A FEW
SHOWERS CONTINUE OVER NORTHERN NORTH DAKOTA AS A SHORT WAVE MOVES
THROUGH THE NORTHERN STREAM.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...UPPER LOW STARTS TO
OPEN UP AND PROGRESS EASTERLY. A FEW LIGHT SHOWERS MAY WRAP INTO
THE AREA FROM THIS THROUGH THE EARLY EVENING...THOUGH THE BULK OF
THE PRECIPITATION WILL REMAIN WELL TO THE SOUTHEAST OF THE AREA.
IN THE MEANTIME...A SERIES OF SHORT WAVES WILL CONTINUE TO MOVE
THROUGH THE NORTHERN STREAM OVER NORTHERN NORTH DAKOTA. THIS WILL
KEEP CHANCES FOR SHOWERS GOING THROUGH THE EVENING OVER THE NORTH
BEFORE TAPERING TOWARDS EARLY MORNING. AMPLE LOW LEVEL MOISTURE
REMAINS IN PLACE WHICH WILL KEEP LOW CLOUD COVER OVER THE AREA.
SOME MODELS SUGGEST THE POSSIBILITY FOR SOME FOG...BUT WILL HOLD
OUT FOR NOW GIVEN THE EXPECTED CONTINUED LOW CLOUD COVER. WITH
THAT SAID...WILL HAVE LATER SHIFTS TAKE A LOOK AT THIS AND IF
THERE IS SOME CLEARING FOG WILL BECOME A CONCERN.
ON THURSDAY...RIDGING DEVELOPS OVER THE AREA WITH SKIES GRADUALLY
CLEARING FROM WEST TO EAST. TEMPERATURES WILL REBOUND TO ABOVE
AVERAGE OVER MOST LOCATIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 23 2015
DETERMINISTIC MODELS AND ENSEMBLE OUTPUT SUPPORT BROAD UPPER RIDGE
OVER NORTH AMERICA EVENTUALLY BREAKING DOWN BY LATE WEEKEND AS
TROUGH MOVES INTO CENTRAL CANADA. THIS PATTERN WILL SUPPORT WELL
ABOVE NORMAL TEMPERATURES...WITH HIGHS IN THE 80S BY SATURDAY BEFORE
DROPPING BACK TO 60S AND 70S SUNDAY AND MONDAY. SOMEWHAT GREATER
UNCERTAINTY EARLY NEXT WEEK AS MODEL SOLUTIONS BEGIN TO
DIVERGE...BUT LOW POPS CONTINUE TO BE WARRANTED SUN/MONDAY AS UPPER
RIDGE BREAKS DOWN. INSTABILITY IS ALSO LACKING...WITH THE GFS ONLY
INDICATING WEAK INSTABILITY ON MONDAY...SO ANY PRECIP WOULD BE
EXPECTED TO BE PREDOMINATELY SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1211 AM CDT THU SEP 24 2015
MVFR CIGS FORECAST TO DETERIORATE TO IFR/LIFR CIGS/VSBYS BETWEEN 08Z-
12Z THURSDAY AND BE MAINTAINED UNTIL 18Z THURSDAY. VFR CONDITIONS
FORECAST THEREAFTER. WINDS REMAIN AT OR BELOW 10KT THROUGH THE
FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JJS
LONG TERM...JNS
AVIATION...KS
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
404 AM CDT THU SEP 24 2015
.SHORT TERM...
(Today and Tonight)
Upper low along the Texas Panhandle and New Mexico state line is
expected move slowly south today and tonight. West Central Texas,
however, will be under the influence of an upper level ridge,
keeping the region for the most part, dry.
The HRRR and Texas Tech WRF short range models do develop
isolated showers in extreme western sections of West Central
Texas....west of a Sweetwater to San Angelo to Sonora line today.
With dry air at the surface, however, showers that develop should
mainly be virga, so will leave out mention of rain. With more
mid/upper level clouds, highs today should be in the lower 90s. It
will be cooler tonight with lows in the lower and mid 60s, due to
light winds and dry air.
.LONG TERM...
(Friday through next Wednesday)
Currently, an upper level low is slowly moving south through
eastern New Mexico, causing the ridge over our area to weaken.
Another more pronounced low is located over northeastern Nebraska.
Both of these features are expected to move south through our area
between now and Saturday. The first, weaker wave will move through
tomorrow, with the second one in Nebraska, moving through
Saturday. Models don`t completely agree on exact path, strength,
or timing of the feature Saturday. However, with the ridge
weakened, and the shortwave moving through, it was enough to
introduce low end slight chance PoPs across our western counties
on Saturday. While we will have a chance for precipitation, we are
not expecting widespread coverage or heavy rainfall.
Along with the rain chances on Saturday, we will see cooler
temperatures both Friday and Saturday under the weakened ridge.
An upper level low will remain nearly stationary over southern
Texas from Saturday night into early next week, but isn`t expected
to result in any precipitation in our area. By Monday, a gradual
warm-up is expected to begin as the ridge re-establishes itself
over the area through the second half of next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 91 66 88 65 / 5 5 10 10
San Angelo 92 64 89 63 / 5 5 10 10
Junction 91 64 90 61 / 0 5 10 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
04/20
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1123 PM CDT WED SEP 23 2015
.AVIATION...
/06Z TAFS/
The convection to the west of the CWA has continued to weaken,
although additional showers and thunderstorms continue farther
west toward the NM border. No precipitation is anticipated
tonight, but a good deal of mid/high clouds will stream across the
area through early Thursday. Light south and southeast winds will
continue tonight, shifting from the east and northeast at 6-8 kts
Thursday afternoon. A few thunderstorms are not out of the
question tomorrow afternoon, mainly west of a KSWW-KSJT line.
However, uncertainty and limited coverage will preclude mention of
this activity in the forecast.
&&
.PREV DISCUSSION... /ISSUED 807 PM CDT WED SEP 23 2015/
UPDATE...
Updated the forecast to increase cloud cover across the northern
and western portions of the forecast area based on the latest
observations/trends. A line of showers and thunderstorms extended
from near Big Spring to Fort Stockton, and this line continues to
move east southeast at 20 mph. This area of precipitation will
start to outrun the moisture/instability axis to our west during
the next few hours, and it should gradually weaken as it
approaches our western counties. However, it may hold together
long enough to give areas west of an Ozona to Robert Lee to
Haskell line some light rainfall, where isolated showers were
added to the forecast through 1 AM. The latest HRRR supports this
scenario as well.
PREV DISCUSSION... /ISSUED 720 PM CDT WED SEP 23 2015/
AVIATION...
/00Z TAFS/
A line of showers and thunderstorms continues to march east across
the Permian Basin this evening, but should rapidly weaken as it
approaches the Concho Valley as it moves into a much more stable
environment. Scattered to broken mid/high clouds are expected
overnight and early Thursday, with a diurnal cu field of 6-7 kft
developing by midday. Expect light southeast winds overnight,
becoming southerly late tonight through 18z, shifting to the east
Thursday afternoon.
PREV DISCUSSION... /ISSUED 342 PM CDT WED SEP 23 2015/
SHORT TERM...
(Tonight and Thursday)
Dry and warm conditions will continue through Thursday, with
slightly above normal temperatures continuing. Showers and a few
thunderstorms have develop across the higher terrain of
southeastern New Mexico this afternoon, with showers also
extending northeast into the southern Panhandle and western
Oklahoma. This activity has developed in association with a weak
mid level trough over the southern Rockies and upslope flow across
the higher terrain. Some of this activity may clip extreme
northwest portions of the Big Country through early evening but
most of it will stay north and west of the area, so no POPs were
added at this time.
The latest 4km Texas Tech WRF develops scattered convection across
the area on Thursday, while the NAM, GFS remain dry. Cannot
discount the WRF entirely, as the ridge begins weakening and
aforementioned mid level trough sinks south across eastern New
Mexico and far west Texas. Any convection that does develop will
most likely remain west of the area and decided to keep the
forecast dry for now, which matches well with neighboring offices.
Lows tonight will be in the 60s, with highs Thursday near 90
degrees.
LONG TERM...
(Thursday Night through Wednesday)
Still considering the chance of rain for Friday. GFS and the TTU
WRF have been indicating a small chance of showers and storms for
Friday across portions of West Central Texas, as a weak cold front
moves into the area. Instability is a little marginal and the best
lift may be early as a weak shortwave rotates through the area. At
this point, not sure there is enough there to warrant a mention
quite yet, but if these trends continue, may need to insert PoPs
at some point later this week.
Upper level ridge remains off to the west for much of the extended
time frame, while an upper level low develops off to the east.
This places West Central Texas largely in northerly flow aloft for
much of next week. Should have a series of weak cold fronts move
across the area. No cold air coming, but perhaps something closer
to normal than we have been the last few weeks.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 66 91 68 88 / 10 0 5 10
San Angelo 64 91 66 90 / 10 0 5 10
Junction 63 90 65 90 / 5 0 5 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Johnson
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
258 AM CDT THU SEP 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CDT THU SEP 24 2015
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING UPPER LEVEL
LOW/TROUGH SPINNING OVER EASTERN NEBRASKA WITH SEVERAL PIECES OF
ENERGY ROTATING AROUND THE UPPER LEVEL TROUGH INTO THE NORTHERN
PLAINS AND UPPER MIDWEST. LATEST KARX RADAR SHOWS LIGHT RAIN SHOWERS
OVER SOUTHEAST MINNESOTA/WESTERN WISCONSIN IN ASSOCIATION WITH WEAK
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN.
THE 24.00Z GFS/NAM AND 24.05Z RAP SUGGEST WEAK IMPULSES ROTATING
AROUND UPPER LEVEL TROUGH TO LIFT NORTHWARD INTO PARTS OF NORTHERN
IOWA/SOUTHERN MINNESOTA TODAY. 24.00Z MODELS SUGGEST WEAK
FORCING/MOISTURE CONVERGENCE TO LIFT NORTHWARD ALONG WITH THE
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN TODAY. IN
ADDITION...SURFACE RIDGE BUILDS INTO THE EASTERN WISCONSIN AFTER 18Z
TODAY. EXPECT THE LIGHT RAIN SHOWERS TO LINGER ACROSS THE FAR
NORTHERN/NORTHWEST PARTS OF THE FORECAST AREA EARLY THIS MORNING
AND TRACK NORTHWARD OUT OF THE FORECAST AREA BY 18Z TODAY.
TONIGHT...WITH SURFACE RIDGE BUILDING INTO THE FORECAST AREA AND
LIGHT WINDS NEAR SURFACE BOUNDARY LAYER AND ALOFT. PATCHY FOG IS A
POSSIBILITY IN RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN. BIG
QUESTION WILL BE IF CLOUDS CLEAR OUT OF THE FORECAST AREA IN TIME TO
ALLOW FOR INVERSION TO DEVELOP AND FOG FORMATION. THE 24.00Z GFS/NAM
SHOW SLIGHT DIFFERENCES IN TIMING OF THE CLOUDS TO CLEAR FROM NORTH
TO SOUTH ACROSS THE FORECAST AREA...PER RELATIVE HUMIDITY FIELDS.
FOR NOW...HAVE LEFT MENTION OF PATCHY FOG IN RIVER VALLEYS AND THE
PREFERRED AREAS OF CENTRAL WISCONSIN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 AM CDT THU SEP 24 2015
MAIN FORECAST CONCERN IS FOG FORMATION FRIDAY NIGHT INTO SATURDAY
MORNING IN RIVER VALLEYS AND CENTRAL WISCONSIN. SURFACE RIDGE AND
RIDGING ALOFT OVER THE GREAT LAKES REGION WILL DOMINATE THE AREA
FRIDAY INTO SATURDAY NIGHT. WITH CLEAR SKIES...LIGHT WINDS NEAR
THE SURFACE BOUNDARY LAYER...AND STRONG INVERSION DEVELOPS AFTER
06Z SATURDAY...FOG WILL BE POSSIBLE IN RIVER VALLEYS AND IN PARTS
OF CENTRAL WISCONSIN FRIDAY NIGHT INTO EARLY SATURDAY MORNING.
INTRODUCED PATCHY FOG FROM 08-14Z SATURDAY.
WITH SURFACE/UPPER LEVEL RIDGE IN CONTROL OF THE AREA...DRY WEATHER
CAN BE EXPECTED FRIDAY INTO SATURDAY. TEMPERATURES FRIDAY INTO
SATURDAY WILL REMAIN ABOVE NORMAL...WITH THE 24.00Z GFS/NAM/ECMWF
INDICATING 925MB TEMPERATURES RANGING FROM PLUS 17 TO PLUS 19
DEGREES CELSIUS ACROSS THE FORECAST AREA.
SUNDAY INTO WEDNESDAY...FORECAST CONCERNS ARE TEMPERATURES THROUGH
THE PERIOD AND PRECIPITATION CHANCES TUESDAY INTO WEDNESDAY. THE
24.00Z GFS/GEM/ECMWF SHOW SIGNIFICANT DIFFERENCES ON TIMING/STRENGTH
OF UPPER LEVEL TROUGH DIGGING OVER THE GREAT LAKES REGION AND
EMBEDDED SHORTWAVE ENERGY IN THE UPPER LEVEL TROUGH MONDAY INTO
WEDNESDAY. THIS WILL HAVE IMPACTS ON TIMING OF SMALL PRECIPITATION
CHANCES TUESDAY INTO WEDNESDAY. TEMPERATURES WILL REMAIN ABOVE
NORMAL SUNDAY INTO MONDAY...AS WARM AIR ADVECTS INTO FORECAST AREA
OUT AHEAD OF SHORTWAVE ENERGY/SURFACE FRONT PUSHING INTO THE
NORTHERN MINNESOTA AND OVER LAKE SUPERIOR. COOLER AIR IS EXPECTED
TO FILTER IN BEHIND SURFACE FRONT/SHORTWAVE TUESDAY INTO
WEDNESDAY...AS THE 24.00Z GFS/ECMWF SUGGEST PLUS 3 TO PLUS 10
DEGREES CELSIUS BY 12Z WEDNESDAY ACROSS FORECAST AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1135 PM CDT WED SEP 23 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. A FEW
SHOWERS ARE POSSIBLE AT KRST OVERNIGHT AS A WEAK SHORTWAVE MOVES
THROUGH. OTHERWISE SCATTERED TO BROKEN MID TO HIGH LEVEL CLOUDS
WILL BE SEEN AT THE TAF SITES. PLAN ON BASES OF AROUND 5 KFT AT
KRST OVERNIGHT INCREASING TO 12 KFT BY MID MORNING THURSDAY. AT
KLSE...CLOUD BASES ARE EXPECTED TO STAY ABOVE 10KFT THROUGH
THURSDAY AFTERNOON. HIGH PRESSURE BUILDS IN THURSDAY AFTERNOON
INTO THURSDAY EVENING WITH LIGHT WINDS EXPECTED BY THURSDAY
EVENING. LOOK FOR THE CLOUDS TO GRADUALLY SCATTER THURSDAY NIGHT
WITH THE POTENTIAL FOR SOME VALLEY FOG AT KLSE...DEPENDING ON
CLOUD COVER AND WHETHER DRIER AIR WORKS IN FROM THE EAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1054 AM EDT THU SEP 24 2015
.SYNOPSIS...
A STRONG HIGH PRESSURE SYSTEM FROM CANADA WILL BUILD SOUTHWARD
ACROSS THE NORTHEASTERN UNITED STATES THROUGH THE WEEKEND. LOW
PRESSURE LOCATED OFF OF THE NORTH CAROLINA COAST WILL GRADUALLY
PUSH NORTHWARD THROUGH THE WEEKEND, MOVING EAST OF THE AREA EARLY
NEXT WEEK. A COLD FRONT WILL CROSS THE REGION AROUND MIDWEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SUNNY DAY IS IN PROGRESS WITH THE SUN FILTERED BY VARIABLY THIN
CIRRUS OVER THE SOUTHERN PART OF OUR FORECAST AREA...MAINLY S OF
I-78.
RAISED TEMPS A TOUCH..ABOUT 1-2F WITH 12Z HRRR ASSISTANCE. BASICALLY
AROUND 80F OR 4 TO 8 DEGREES ABOVE NORMAL. GUSTS INCREASED 2-3 MPH
THIS AFTN SO THAT WE SEE GUSTS 15-20 MPH THIS AFTN, STRONGEST
NEAR THE COAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
AT THE SURFACE, THE HIGH WILL CONTINUE BUILDING SOUTH, RESULTING
IN AN INCREASING PRESSURE GRADIENT OVER THE REGION. THUS, COULD
HAVE A BREEZY NIGHT PRIMARILY NEAR THE COAST.
IN THE UPPER LEVELS, EXPECT THE MAIN JET AXIS TO PROPAGATE SOUTH. AS
A RESULT, SHOULD SEE INCREASING CIRRUS CLOUDS ACROSS THE REGION.
FOG DEVELOPMENT APPEARS UNLIKELY GIVEN WINDS STAYING A BIT HIGHER
FOR MOST LOCATIONS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THIS PERIOD CONTINUES TO BE LARGELY DOMINATED BY HIGH PRESSURE
ACROSS THE NORTHEASTERN UNITED STATES. HOWEVER, A LOW PRESSURE
SYSTEM TO OUR SOUTH WILL GRADUALLY PUSH NORTHWARD, REMAINING
OFFSHORE, MOVING OFF TO THE NORTHEAST EARLY NEXT WEEK. A COLD FRONT
WILL APPROACH THE AREA AROUND MIDWEEK.
FRIDAY NIGHT THROUGH MONDAY...STRONG CANADIAN HIGH PRESSURE WILL
CONTINUE TO BUILD DOWN FROM CENTRAL CANADA, REMAINING CENTERED TO
OUR NORTH, AND SLIDING EASTWARD THROUGH THIS WEEKEND. THE LOW
PRESSURE SYSTEM OFF THE NORTH/SOUTH CAROLINA COAST RETROGRADES
SLIGHTLY OVER THE NEXT SEVERAL DAYS. AS THIS LOW STARTS TO PUSH
NORTHWARD, WE WILL SEE INCREASING CLOUDS ACROSS OUR AREA AND SOME
LIGHT SHOWERS MAKING THEIR WAY INTO THE DELMARVA AND SOUTHERN NEW
JERSEY.
WHILE THERE CONTINUES TO BE CONSIDERABLE DIFFERENCE IN THE MODEL
GUIDANCE, THERE IS A MORE DISCERNIBLE DRYING TREND THAN HAS BEEN SEEN
THE PAST SEVERAL DAYS. THE GFS IS NOW TRENDING A BIT DRIER WITH THE
LOW AS IT PUSHES NORTH AND SEEMS TO BE STARTING TO MOVE MORE TOWARD
THE REMAINING MODEL CONSENSUS. WE CONTINUE TO HAVE LOWER CONFIDENCE
IN THIS FORECAST THAN WE WOULD LIKE AT THIS TIME. WE CONTINUE TO
KEEP THE HIGHEST CHANCES FOR RAIN ACROSS THE SOUTHERN AREAS THROUGH
MUCH OF THE WEEKEND.
A SHORTWAVE MOVES THROUGH THE MID LEVELS LATE IN THE WEEKEND AND
THIS MAY ACTUALLY HELP TO BRING SOME THE SHOWER ACTIVITY FURTHER
NORTH. WE HAVE CHANCES FOR RAIN EXTENDING FROM THE LEHIGH VALLEY
SOUTH AND EAST THROUGH MONDAY WITH THE CHANCES DECREASING THROUGH
MONDAY NIGHT AS THE SHORTWAVE AND THE LOW PUSH TO THE EAST.
THE ONE THING REMAINS CERTAIN IS WE WILL SEE NORTHEASTERLY WINDS
INCREASE AGAIN, ESPECIALLY ALONG THE COASTAL AREAS, AS THE HIGH
BUILDS SOUTH AND THE LOW PUSHES NORTH. WINDS WILL BE QUITE GUSTY
THROUGH THE WEEKEND WITH GUSTS UP TO 25 TO 30 MPH POSSIBLE. WINDS
ALONG THE COAST MAY BE NEAR 30 TO 40 MPH AT TIMES, ESPECIALLY ON
SATURDAY.
TUESDAY THROUGH WEDNESDAY...WE SHOULD DRY OUT AS THE LOW PUSHES
FURTHER TO THE EAST AND HIGH PRESSURE BRIEFLY RETURNS TO THE AREA. A
COLD FRONT WILL DROP DOWN FROM THE NORTHWEST AROUND WEDNESDAY BUT
CONSIDERABLE TIMING DIFFERENCE WITH THIS FEATURE AT THIS TIME.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY, AND SURROUNDING AREAS.
THROUGH THIS AFTERNOON...VFR CIRRUS. NE WIND SHOULD SEE GUSTS
INCREASE TO AROUND 14-19 KT THIS AFTERNOON.
TONIGHT...VFR WITH THE LOWER CLOUDS STREAMING SWWD IN THE WESTERN
ATLANTIC POSSIBLY GRAZING KACY KMIV TONIGHT... 2000 FT SCT? NE
WIND GUSTS 10 TO 15 KT EXCEPT AROUND 20 KT VCNTY KACY AS THE
GRADIENT TIGHTENS WITH AN INJECTION OF COOL AIR ARRIVING FROM THE
NORTHEAST DURING THE NIGHT STEEPING THE LOW LEVEL LAPSE RATES.
OUTLOOK...
FRIDAY THROUGH SUNDAY...MAINLY VFR CONDITIONS EXPECTED. MVFR
CONDITIONS POSSIBLE IN SHOWERS FROM KPHL, SOUTH AND EAST AS A LOW
OFF THE CAROLINA COAST PUSHES NORTHWARD. NORTHEAST WINDS AROUND 10
TO 15 KNOTS WITH WIND GUSTS AROUND 15 TO 25 KNOTS. WIND GUSTS ON
SATURDAY AND SUNDAY MAY NEAR 30 KNOTS, MAINLY AT KACY AND POSSIBLY
KMIV.
MONDAY...MAINLY VFR CONDITIONS EXPECTED. MVFR CONDITIONS POSSIBLE IN
SHOWERS ACROSS THE TERMINALS. EAST WINDS AROUND 10 KNOTS OR LESS
WITH GUSTS UP TO 15 TO 20 KNOTS NEAR KACY.
&&
.MARINE...
SMALL CRAFT ADVISORY CONDITIONS WILL BECOME WIDESPREAD LATE TODAY
AND TONIGHT. RIGHT NOW, JUST BELOW SCA IN ANZ450 (NNJ) AND ANZ431
(LOWER DE BAY) BUT NOT CHANGING THE HEADLINE SINCE CONDITIONS ARE
EXPECTED TO WORSEN LATE TODAY AND TONIGHT. HAVE IMPLIED THIS IN
THE UPDATED MWW. BY DAYBREAK FRIDAY NEAR 30 KT GUSTS EXPECTED AND
SEAS INCREASED BY 1 TO 2 FEET FROM THE CURRENT VALUES...8 FT OFF
DE AND S NJ AND 5 FT AT THE DE BAY ENTRANCE. CHOP DEVELOPING ON
TOP OF THE LONGER PERIOD ENE SWELL.
FOR THE UPPER DELAWARE BAY, SOME GUSTS AROUND 20 ARE POSSIBLE
TODAY AND THIS EVENING, BUT SHOULD STAY BELOW SMALL CRAFT ADVISORY
CONDITIONS.
OUTLOOK...
FRIDAY THROUGH MONDAY...SEAS WILL CONTINUE TO REMAIN ELEVATED
THROUGH AT LEAST THE WEEKEND, ABOVE 5 FEET, AND A SMALL CRAFT
ADVISORY LOOKS LIKE IT WILL BE NEEDED THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK.
FOR SEAS, WAVEWATCH GUIDANCE HAS BEEN STEADILY DECREASING WITH EACH
NEW MODEL RUN. STILL ANTICIPATE THAT WAVES WILL RISE TO 7 TO 10 FEET
BY THIS WEEKEND. HIGHEST SEAS ARE EXPECTED TO REMAIN ACROSS THE
SOUTHERN WATERS. SHOULD SEAS REACH AND/OR EXCEED 10 FEET NEAR THE
COAST, A HIGH SURF ADVISORY MAY BE NEEDED.
FOR WINDS, NORTHEASTERLY WINDS WILL CONTINUE THROUGH THE WEEKEND.
WINDS WILL GENERALLY BE AROUND 10 TO 15 KNOTS WITH HIGHER GUSTS UP
TO 30 KNOTS POSSIBLE, MAINLY DURING THE DAYTIME HOURS WHEN BETTER
MIXING OCCURS. WINDS MAY DROP BELOW 25 KNOTS FOR A PERIOD OF TIME
DURING THE OVERNIGHT HOURS, MAINLY NORTHERN WATERS, WILL PICK RIGHT
BACK UP AGAIN ON DURING THE DAYTIME WINDS ACROSS THE NORTHERN WATERS
WILL BE SLIGHTLY LESS THAN THOSE TO THE SOUTH AS THE GRADIENT WILL
BE WEAKER AS YOU HEAD NORTH. THERE IS CHANCE THAT GALE FORCE
GUSTS MAY OCCUR OVER THE WEEKEND, MAINLY ACROSS THE SOUTHERN
WATERS.
WINDS WILL DECREASE ON MONDAY AS THE GRADIENT REALLY STARTS TO
WEAKEN ACROSS THE AREA WATERS. WE SHOULD LARGELY LOSE THE HIGHER
GUSTS AND GENERALLY SEE WINDS AROUND 10 TO 15 KNOTS WITH GUSTS
AROUND 20 KNOTS.
&&
.TIDES/COASTAL FLOODING...
A PERSISTENT ONSHORE FLOW WILL CONTINUE TO ENHANCE THE POTENTIAL FOR
SOME MINOR COASTAL FLOODING ALONG THE OCEANFRONT OF NEW JERSEY AND
DELAWARE. MINOR FLOODING HAS OCCURRED IN DE LATE YESTERDAY AND
IN ALL LIKELIHOOD WE WILL BE ISSUING AN ADVISORY AT 3PM FOR THE
FRIDAY EVENING HIGH TIDE CYCLE AND INCLUDE SOME INFORMATION ABOUT
THIS EVENING.
WIDESPREAD MINOR COASTAL FLOODING IS EXPECTED OVER THE WEEKEND
ALONG THE DE COAST AND PROBABLY THE SNJ COAST.
HIGH TIDE CYCLES STARING ON FRIDAY NIGHT AND CONTINUING THROUGH
MONDAY MORNING ARE VULNERABLE TO COASTAL FLOODING AND WILL NEED TO
BE MONITORED. WHILE THE CHANCES ARE HIGH FOR MINOR TIDAL FLOODING
TO OCCUR ALONG THE OCEANFRONT AND DELAWARE BAY, THERE IS A CHANCE
THAT TIDAL FLOODING MAY BE AN ISSUE ALONG THE TIDAL PORTION OF THE
DELAWARE RIVER.
&&
.RIP CURRENTS...
A HIGH RISK FOR THE DEVELOPMENT OF DANGEROUS RIP CURRENTS EXISTS
ALONG THE ENTIRE NEW JERSEY SHORE AND THE DELAWARE BEACHES THROUGH
AT LEAST THIS EVENING.
BASED ON THE EXPECTATION THAT THE FLOW WILL REMAIN PRIMARILY FROM
THE NORTHEAST INTO THE WEEKEND, WE WILL LIKELY SEE A PROLONGED
PERIOD OF MODERATE OR HIGH RIP CURRENT FORMATION RISK ALONG OUR
COAST INTO EARLY NEXT WEEK.
&&
.CLIMATE...
A TOP 8 WARMEST SEPTEMBER APPEARS ASSURED FOR PORTIONS OF OUR
FORECAST AREA. DATA CHECKED THROUGH 9AM THIS THURSDAY MORNING
INCLUDING PROJECTIONS THROUGH THE 30TH FROM OUR GRIDS.
INFORMATION PUBLISHED BELOW IS ONLY FOR THE LONG TERM CLIMATE SITES
THAT SHOULD VERIFY CLOSE TO THE RANKING PROJECTIONS POSTED BELOW.
PHL 73.9-74.0 RANK #3 POR 1874 NORMAL 69.1 PROJECTING AROUND PLUS
3.8F
1881 75.4
1931 74.1
1930 74.1
2015 73.9?
2005 73.8
2010 72.9
ABE 68.9-69.0 RANK #4 POR 1922 NORMAL 63.9 PROJECTING AROUND PLUS
5.0F
1961 70.8
1980 70.3
1931 69.4
2015 68.9?
2005 68.7
1959 68.2
ILG 72.0 RANK #5 POR 1917 NORMAL 67.8 PROJECTING PLUS 4.2F
EVEN THOUGH WE LIST AN ALL TIME MONTHLY MAX AVERAGE TEMP IN 1895 FOR
KILG...THE POR WAS INTERRUPTED IN OUR POSTED MONTHLY MEAN TEMP DATA
FOR THE PERIOD 1897-1916.
1895 72.9
1961 72.5
1930 72.3
1970 72.1
1931 72.1
2015 72.0?
2005 71.8
1921 71.8
1925 71.4
ACY 71.2 RANK #7 POR 1874 NORMAL 67.2 PROJECTING PLUS 4.0
1961 73.3
1881 72.8
1931 72.3
1930 72.3
1921 71.7
1933 71.5
2005 71.3
2015 71.2?
2010 71.0
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NJZ014-
024>026.
DE...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR DEZ004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ431-450>455.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...DRAG 1053
SHORT TERM...JOHNSON
LONG TERM...MEOLA
AVIATION...DRAG/MEOLA 1053
MARINE...DRAG/MEOLA 1053
TIDES/COASTAL FLOODING...1053
RIP CURRENTS...1053
CLIMATE...1053
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1033 AM CDT THU SEP 24 2015
.UPDATE...SOME SHORT WAVE ENERGY INTO LOWER SE TX AND DEEPENING
MOISTURE OVER ACADIANA NOTED. WILL GO ALONG WITH HRRR AND INCLUDE
A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON.
&&
.MARINE...INCREASING GRADIENT FROM THE NORTHEAST OVER THE EASTERN
OUTER WATERS. ADDED CAUTION FOR THOSE WATERS EAST OF INTRACOASTAL
CITY THROUGH THIS AFTERNOON.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT THU SEP 24 2015/
AVIATION... HIGH PRESSURE CONTINUES TO LOSE ITS GRIP OVER THE
REGION WITH PRECIPITABLE WATER VALUES HEADING UPWARD. WITH
THAT...RADAR SHOWING SHOWERS OVER THE NEAR COASTAL WATERS.
EXPECTING BULK OF CONVECTION TODAY TO REMAIN OVER THE NEAR
COASTAL WATERS...BUT COULD SEE SOME DEVELOPMENT IN THE VICINITY
OF THE BPT TERMINAL. CARRYING VCSH THERE. OTHERWISE...VFR EXPECTED
WHILE WINDS REMAIN LIGHT.
23
PREV DISCUSSION... /ISSUED 505 AM CDT THU SEP 24 2015/
DISCUSSION...
VERY QUIET PATTERN ACROSS THE SOUTHERN STATES AS HIGH PRESSURE
REMAINS IN CONTROL. A FEW SHOWERS NOTED ON RADAR GENERALLY FROM 20
TO BEYOND 60 NM SOUTH OF THE COAST. SHOWERS ARE MOVING WESTWARD.
MOISTURE HAS BEEN SLIPPING BACK INTO THE NW GULF REGION OVER THE
LAST DAY OR TWO AS DEW POINTS ARE NOW HOLDING IN THE UPPER 60S
ALONG THE I-10 CORRIDOR AND MID 60 ACROSS THE LAKES REGION OF SE
TX AND CNTRL LA THIS MRNG.
ALOFT THE RIDGE WILL REMAIN IN PLACE OVER THE NEXT SEVERAL DAYS
BEFORE BEGINNING TO BREAK OVER THE WEEKEND. THIS WILL ALLOW BETTER
SHOWER DEVELOPMENT ON SUNDAY INTO MONDAY. TEMPERATURES WILL BE
RUNNING NEAR NORMAL DURING THE DAY "AROUND 90" AND A BIT WARMER
DURING THE OVERNIGHT HOURS "AROUND 70 DEGREES". THEREFORE WE ARE
NOT LOOKING FOR A BIG CHANGE FOR THE ATMOSPHERE.
TOWARDS THE BEGINNING OF NEXT WEEK LOOKING TO SEE A SURFACE LOW
TO MOVE OFF OF THE YUCATAN PENINSULA NORTHWARD INTO EASTERN LA
AND SOUTHERN MISSISSIPPI TOWARDS TUESDAY. AS A RESULT RAIN
CHANCES WILL BE LIMITED OVER OUR REGION.
19
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 91 67 91 65 / 20 10 10 10
LCH 90 70 90 70 / 20 10 20 10
LFT 90 70 89 68 / 20 10 20 10
BPT 89 70 91 70 / 20 10 20 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION UNTIL 7 PM CDT THIS EVENING FOR
GMZ475.
&&
$$
PUBLIC...11
AREA FORECAST DISCUSSION
NWS BISMARCK ND
938 AM CDT THU SEP 24 2015
.UPDATE...
ISSUED AT 938 AM CDT THU SEP 24 2015
POPS WERE SLIGHTLY ADJUSTED TO THE RADAR...OTHERWISE THE FORECAST
IN ON TRACK.
UPDATE ISSUED AT 625 AM CDT THU SEP 24 2015
GIVEN WEBCAM TRENDS THROUGH 1120 UTC...EXPANDED THE DENSE FOG
ADVISORY INTO THE SOURIS BASIN. FLOOD ADVISORIES ACROSS THE BASIN
WERE ALSO EXTENDED THROUGH 1630-1700 UTC TODAY TO ASSESS ANY FLOOD
IMPACTS FROM HEAVY RAINFALL OVERNIGHT.
UPDATE ISSUED AT 319 AM CDT THU SEP 24 2015
A DENSE FOG ADVISORY WILL BE ISSUED FOR PORTIONS OF SOUTH CENTRAL
NORTH DAKOTA INCLUDING THE JAMES RIVER VALLEY. WEBCAMS AND SURFACE
OBSERVATIONS SUPPORT AN ADVISORY AND THE HRRR VISIBILITY FORECAST
MAINTAINS LESS THAN ONE HALF MILE THROUGH THE MORNING. THIS
ADVISORY MAY NEED TO BE EXTENDED WEST AND NORTH AT SOME POINT
LATER THIS MORNING. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 149 AM CDT THU SEP 24 2015
LATEST WATER VAPOR IMAGERY SHOWS A DISTINCT SHORTWAVE NEAR
SHERWOOD MOVING EAST WITH TIME. A CONTINUOUS BAND OF SHOWERS AND
THUNDERSTORMS HAS PROMPTED THE ISSUANCE OF A FEW AREAL FLOOD
ADVISORIES ACROSS NORTH CENTRAL NORTH DAKOTA THROUGH 0600 AM CDT.
EXPECT THE PRECIPITATION AREA TO GRADUALLY SHIFT EAST AND EXIT
THE TURTLE MOUNTAINS BETWEEN 15Z-17Z THURSDAY.
OTHERWISE...STRATUS AND POTENTIALLY WIDESPREAD DENSE FOG TAKE
CONTROL OVER THE REST OF THE FORECAST AREA THROUGH THE MORNING
HOURS. THE RAP13/HRRR/NAM REMAIN PERSISTENT IN DEVELOPING LOW
VISIBILITIES/LESS THAN ONE HALF MILE...AND CLOUDS BETWEEN 200FT
AND 1000FT THROUGH 18Z THURSDAY. CLOUDS HAVE BEEN LOWERING HERE
AT BISMARCK...AS WELL AS OTHER SURROUNDING SURFACE OBSERVATIONAL
SITES WHICH FURTHER SUPPORT THE STRATUS AND FOG. MAY BE ISSUING A
DENSE FOG ADVISORY AT SOME POINT AFTER THIS DISCUSSION IS
DISSEMINATED. MID/UPPER LEVEL RIDGE BEGINS TO BUILD NORTHEAST
THURSDAY AFTERNOON AS HEIGHTS RISE FROM SOUTHWEST TO NORTHEAST.
DECREASING CLOUDS WITH AMPLE SUNSHINE RETURN DURING THE AFTERNOON
HOURS. HIGHS IN THE 70S TODAY WITH 80F IN THE FAR WEST.
ALTHOUGH DRYING AND WARMING CONDITIONS COMMENCE LATER TODAY...NAM
BUFKIT SOUNDINGS AND TO SOME EXTENT THE GFS SHOW A SHALLOW LAYER
OF LOW CLOUDS/FOG AGAIN DEVELOPING OVER SOUTH CENTRAL...KBIS/KJMS
AFTER MIDNIGHT THURSDAY INTO EARLY FRIDAY MORNING. THIS IS DUE TO
A WEAK BUT PERSISTENT LOW LEVEL EAST TO SOUTHEAST WIND.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 149 AM CDT THU SEP 24 2015
A WARM UP INTO SATURDAY FOLLOWED BY A COOL DOWN EARLY NEXT WEEK
HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD
AGREEMENT ON AN AMPLIFYING UPPER LEVEL RIDGE FROM THE SOUTHWEST US
INTO THE NORTHERN PLAINS THURSDAY INTO FRIDAY. THIS RIDGE IS
FORECAST TO BREAK DOWN BY SUNDAY...WITH A POTENTIAL BROAD UPPER
LEVEL TROUGH DEVELOPING ACROSS THE REGION EARLY NEXT WEEK.
THUS...TEMPERATURES ARE FORECAST TO WARM INTO SATURDAY...WITH
WIDESPREAD HIGHS IN THE 80S POSSIBLE SATURDAY AHEAD OF A STRONG
COLD FRONT FORECAST TO PROPAGATE ACROSS THE STATE SATURDAY NIGHT
INTO SUNDAY. THEREAFTER...A RETURN TO COOLER BUT STILL NEAR
NORMAL HIGHS IN THE 60S ARE EXPECTED NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 625 AM CDT THU SEP 24 2015
IFR/LIFR CIGS/VSBYS WILL BE MAINTAINED THROUGH 18Z BEFORE CIGS/VSBYS
LIFT TO MVFR AND THEN VFR 18Z-20Z THURSDAY. LIGHT SOUTHEAST WINDS AT
KBIS AND KJMS MAY LEAD TO MVFR CIGS/VSBYS AFTER 06Z FRIDAY. WITH
STILL UNCERTAINTY THIS FAR OUT...HAVE OPTED TO MENTIONED VCFG AND
SCT CLOUDS AT 500FT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CDT /11 AM MDT/ TODAY FOR
NDZ002>004-010>012-021>023-034>037-042-045>048-050-051.
&&
$$
UPDATE...AC
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
629 AM CDT THU SEP 24 2015
.UPDATE...
ISSUED AT 625 AM CDT THU SEP 24 2015
GIVEN WEBCAM TRENDS THROUGH 1120 UTC...EXPANDED THE DENSE FOG
ADVISORY INTO THE SOURIS BASIN. FLOOD ADVISORIES ACROSS THE BASIN
WERE ALSO EXTENDED THROUGH 1630-1700 UTC TODAY TO ASSESS ANY FLOOD
IMPACTS FROM HEAVY RAINFALL OVERNIGHT.
UPDATE ISSUED AT 319 AM CDT THU SEP 24 2015
A DENSE FOG ADVISORY WILL BE ISSUED FOR PORTIONS OF SOUTH CENTRAL
NORTH DAKOTA INCLUDING THE JAMES RIVER VALLEY. WEBCAMS AND SURFACE
OBSERVATIONS SUPPORT AN ADVISORY AND THE HRRR VISIBILITY FORECAST
MAINTAINS LESS THAN ONE HALF MILE THROUGH THE MORNING. THIS
ADVISORY MAY NEED TO BE EXTENDED WEST AND NORTH AT SOME POINT
LATER THIS MORNING. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 149 AM CDT THU SEP 24 2015
LATEST WATER VAPOR IMAGERY SHOWS A DISTINCT SHORTWAVE NEAR
SHERWOOD MOVING EAST WITH TIME. A CONTINUOUS BAND OF SHOWERS AND
THUNDERSTORMS HAS PROMPTED THE ISSUANCE OF A FEW AREAL FLOOD
ADVISORIES ACROSS NORTH CENTRAL NORTH DAKOTA THROUGH 0600 AM CDT.
EXPECT THE PRECIPITATION AREA TO GRADUALLY SHIFT EAST AND EXIT
THE TURTLE MOUNTAINS BETWEEN 15Z-17Z THURSDAY.
OTHERWISE...STRATUS AND POTENTIALLY WIDESPREAD DENSE FOG TAKE
CONTROL OVER THE REST OF THE FORECAST AREA THROUGH THE MORNING
HOURS. THE RAP13/HRRR/NAM REMAIN PERSISTENT IN DEVELOPING LOW
VISIBILITIES/LESS THAN ONE HALF MILE...AND CLOUDS BETWEEN 200FT
AND 1000FT THROUGH 18Z THURSDAY. CLOUDS HAVE BEEN LOWERING HERE
AT BISMARCK...AS WELL AS OTHER SURROUNDING SURFACE OBSERVATIONAL
SITES WHICH FURTHER SUPPORT THE STRATUS AND FOG. MAY BE ISSUING A
DENSE FOG ADVISORY AT SOME POINT AFTER THIS DISCUSSION IS
DISSEMINATED. MID/UPPER LEVEL RIDGE BEGINS TO BUILD NORTHEAST
THURSDAY AFTERNOON AS HEIGHTS RISE FROM SOUTHWEST TO NORTHEAST.
DECREASING CLOUDS WITH AMPLE SUNSHINE RETURN DURING THE AFTERNOON
HOURS. HIGHS IN THE 70S TODAY WITH 80F IN THE FAR WEST.
ALTHOUGH DRYING AND WARMING CONDITIONS COMMENCE LATER TODAY...NAM
BUFKIT SOUNDINGS AND TO SOME EXTENT THE GFS SHOW A SHALLOW LAYER
OF LOW CLOUDS/FOG AGAIN DEVELOPING OVER SOUTH CENTRAL...KBIS/KJMS
AFTER MIDNIGHT THURSDAY INTO EARLY FRIDAY MORNING. THIS IS DUE TO
A WEAK BUT PERSISTENT LOW LEVEL EAST TO SOUTHEAST WIND.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 149 AM CDT THU SEP 24 2015
A WARM UP INTO SATURDAY FOLLOWED BY A COOL DOWN EARLY NEXT WEEK
HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD
AGREEMENT ON AN AMPLIFYING UPPER LEVEL RIDGE FROM THE SOUTHWEST US
INTO THE NORTHERN PLAINS THURSDAY INTO FRIDAY. THIS RIDGE IS
FORECAST TO BREAK DOWN BY SUNDAY...WITH A POTENTIAL BROAD UPPER
LEVEL TROUGH DEVELOPING ACROSS THE REGION EARLY NEXT WEEK.
THUS...TEMPERATURES ARE FORECAST TO WARM INTO SATURDAY...WITH
WIDESPREAD HIGHS IN THE 80S POSSIBLE SATURDAY AHEAD OF A STRONG
COLD FRONT FORECAST TO PROPAGATE ACROSS THE STATE SATURDAY NIGHT
INTO SUNDAY. THEREAFTER...A RETURN TO COOLER BUT STILL NEAR
NORMAL HIGHS IN THE 60S ARE EXPECTED NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 625 AM CDT THU SEP 24 2015
IFR/LIFR CIGS/VSBYS WILL BE MAINTAINED THROUGH 18Z BEFORE CIGS/VSBYS
LIFT TO MVFR AND THEN VFR 18Z-20Z THURSDAY. LIGHT SOUTHEAST WINDS AT
KBIS AND KJMS MAY LEAD TO MVFR CIGS/VSBYS AFTER 06Z FRIDAY. WITH
STILL UNCERTAINTY THIS FAR OUT...HAVE OPTED TO MENTIONED VCFG AND
SCT CLOUDS AT 500FT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CDT /11 AM MDT/ TODAY FOR
NDZ002>004-010>012-021>023-034>037-042-045>048-050-051.
&&
$$
UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
607 AM CDT THU SEP 24 2015
.AVIATION...
/|12Z TAFS/
VFR next 24 hours. South winds less than 10 KTS will become
east this afternoon.
&&
.PREV DISCUSSION... /ISSUED 404 AM CDT THU SEP 24 2015/
SHORT TERM...
(Today and Tonight)
Upper low along the Texas Panhandle and New Mexico state line is
expected move slowly south today and tonight. West Central Texas,
however, will be under the influence of an upper level ridge,
keeping the region for the most part, dry.
The HRRR and Texas Tech WRF short range models do develop
isolated showers in extreme western sections of West Central
Texas....west of a Sweetwater to San Angelo to Sonora line today.
With dry air at the surface, however, showers that develop should
mainly be virga, so will leave out mention of rain. With more
mid/upper level clouds, highs today should be in the lower 90s. It
will be cooler tonight with lows in the lower and mid 60s, due to
light winds and dry air.
LONG TERM...
(Friday through next Wednesday)
Currently, an upper level low is slowly moving south through
eastern New Mexico, causing the ridge over our area to weaken.
Another more pronounced low is located over northeastern Nebraska.
Both of these features are expected to move south through our area
between now and Saturday. The first, weaker wave will move through
tomorrow, with the second one in Nebraska, moving through
Saturday. Models don`t completely agree on exact path, strength,
or timing of the feature Saturday. However, with the ridge
weakened, and the shortwave moving through, it was enough to
introduce low end slight chance PoPs across our western counties
on Saturday. While we will have a chance for precipitation, we are
not expecting widespread coverage or heavy rainfall.
Along with the rain chances on Saturday, we will see cooler
temperatures both Friday and Saturday under the weakened ridge.
An upper level low will remain nearly stationary over southern
Texas from Saturday night into early next week, but isn`t expected
to result in any precipitation in our area. By Monday, a gradual
warm-up is expected to begin as the ridge re-establishes itself
over the area through the second half of next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 91 66 88 65 / 5 5 10 10
San Angelo 92 64 89 63 / 5 5 10 10
Junction 91 64 90 61 / 0 5 10 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
99/99/04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
608 AM CDT THU SEP 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CDT THU SEP 24 2015
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING UPPER LEVEL
LOW/TROUGH SPINNING OVER EASTERN NEBRASKA WITH SEVERAL PIECES OF
ENERGY ROTATING AROUND THE UPPER LEVEL TROUGH INTO THE NORTHERN
PLAINS AND UPPER MIDWEST. LATEST KARX RADAR SHOWS LIGHT RAIN SHOWERS
OVER SOUTHEAST MINNESOTA/WESTERN WISCONSIN IN ASSOCIATION WITH WEAK
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN.
THE 24.00Z GFS/NAM AND 24.05Z RAP SUGGEST WEAK IMPULSES ROTATING
AROUND UPPER LEVEL TROUGH TO LIFT NORTHWARD INTO PARTS OF NORTHERN
IOWA/SOUTHERN MINNESOTA TODAY. 24.00Z MODELS SUGGEST WEAK
FORCING/MOISTURE CONVERGENCE TO LIFT NORTHWARD ALONG WITH THE
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN TODAY. IN
ADDITION...SURFACE RIDGE BUILDS INTO THE EASTERN WISCONSIN AFTER 18Z
TODAY. EXPECT THE LIGHT RAIN SHOWERS TO LINGER ACROSS THE FAR
NORTHERN/NORTHWEST PARTS OF THE FORECAST AREA EARLY THIS MORNING
AND TRACK NORTHWARD OUT OF THE FORECAST AREA BY 18Z TODAY.
TONIGHT...WITH SURFACE RIDGE BUILDING INTO THE FORECAST AREA AND
LIGHT WINDS NEAR SURFACE BOUNDARY LAYER AND ALOFT. PATCHY FOG IS A
POSSIBILITY IN RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN. BIG
QUESTION WILL BE IF CLOUDS CLEAR OUT OF THE FORECAST AREA IN TIME TO
ALLOW FOR INVERSION TO DEVELOP AND FOG FORMATION. THE 24.00Z GFS/NAM
SHOW SLIGHT DIFFERENCES IN TIMING OF THE CLOUDS TO CLEAR FROM NORTH
TO SOUTH ACROSS THE FORECAST AREA...PER RELATIVE HUMIDITY FIELDS.
FOR NOW...HAVE LEFT MENTION OF PATCHY FOG IN RIVER VALLEYS AND THE
PREFERRED AREAS OF CENTRAL WISCONSIN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 AM CDT THU SEP 24 2015
MAIN FORECAST CONCERN IS FOG FORMATION FRIDAY NIGHT INTO SATURDAY
MORNING IN RIVER VALLEYS AND CENTRAL WISCONSIN. SURFACE RIDGE AND
RIDGING ALOFT OVER THE GREAT LAKES REGION WILL DOMINATE THE AREA
FRIDAY INTO SATURDAY NIGHT. WITH CLEAR SKIES...LIGHT WINDS NEAR
THE SURFACE BOUNDARY LAYER...AND STRONG INVERSION DEVELOPS AFTER
06Z SATURDAY...FOG WILL BE POSSIBLE IN RIVER VALLEYS AND IN PARTS
OF CENTRAL WISCONSIN FRIDAY NIGHT INTO EARLY SATURDAY MORNING.
INTRODUCED PATCHY FOG FROM 08-14Z SATURDAY.
WITH SURFACE/UPPER LEVEL RIDGE IN CONTROL OF THE AREA...DRY WEATHER
CAN BE EXPECTED FRIDAY INTO SATURDAY. TEMPERATURES FRIDAY INTO
SATURDAY WILL REMAIN ABOVE NORMAL...WITH THE 24.00Z GFS/NAM/ECMWF
INDICATING 925MB TEMPERATURES RANGING FROM PLUS 17 TO PLUS 19
DEGREES CELSIUS ACROSS THE FORECAST AREA.
SUNDAY INTO WEDNESDAY...FORECAST CONCERNS ARE TEMPERATURES THROUGH
THE PERIOD AND PRECIPITATION CHANCES TUESDAY INTO WEDNESDAY. THE
24.00Z GFS/GEM/ECMWF SHOW SIGNIFICANT DIFFERENCES ON TIMING/STRENGTH
OF UPPER LEVEL TROUGH DIGGING OVER THE GREAT LAKES REGION AND
EMBEDDED SHORTWAVE ENERGY IN THE UPPER LEVEL TROUGH MONDAY INTO
WEDNESDAY. THIS WILL HAVE IMPACTS ON TIMING OF SMALL PRECIPITATION
CHANCES TUESDAY INTO WEDNESDAY. TEMPERATURES WILL REMAIN ABOVE
NORMAL SUNDAY INTO MONDAY...AS WARM AIR ADVECTS INTO FORECAST AREA
OUT AHEAD OF SHORTWAVE ENERGY/SURFACE FRONT PUSHING INTO THE
NORTHERN MINNESOTA AND OVER LAKE SUPERIOR. COOLER AIR IS EXPECTED
TO FILTER IN BEHIND SURFACE FRONT/SHORTWAVE TUESDAY INTO
WEDNESDAY...AS THE 24.00Z GFS/ECMWF SUGGEST PLUS 3 TO PLUS 10
DEGREES CELSIUS BY 12Z WEDNESDAY ACROSS FORECAST AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 608 AM CDT THU SEP 24 2015
THE SHOWERS THAT MOVED THROUGH SOUTHEAST MINNESOTA EARLIER IN THE
NIGHT HAVE CONTINUED TO SHOW A SLOW NORTHWARD DRIFT AWAY FROM THE
AREA. THE SHOWERS OVER NORTH CENTRAL IOWA ARE ALSO MOVING SLOWLY
NORTH AND WITH THE HI-RES MESO MODELS SUGGESTING THIS ACTIVITY
WILL NOT GET INTO KRST TODAY...WILL INDICATE A DRY FORECAST.
CEILINGS HAVE BEEN VFR AND THE 24.06Z NAM FORECAST SOUNDINGS DO
NOT SUGGEST THIS WILL CHANGE TODAY. DRIER AIR SHOULD WORK INTO
THE AREA OVERNIGHT TO START DISSIPATING THE CLOUDS. THE CONCERN
BECOMES IF THESE CLOUDS WILL BREAK UP SOON ENOUGH TO ALLOW SOME
FOG TO FORM. WITH THE DRIER AIR COMING IN FROM THE EAST...WILL
SHOW THE CLOUDS SCATTERING OUT AT KLSE BEFORE KRST. IF THIS
HAPPENS...THE WINDS WILL BE LIGHT THROUGH A PRETTY DEEP LAYER WITH
SATURATION OCCURRING AT THE SURFACE WHICH SHOULD LEAD TO SOME
VALLEY FOG. WILL ADD A BCFG FOR THIS...BUT IF THE CLOUDS HOLD ON
LONGER...AS THE 24.00Z GFS WOULD SUGGEST...THEN THIS WOULD NOT BE
NEEDED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS JACKSON KY
343 PM EDT THU SEP 24 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 340 PM EDT THU SEP 24 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE TO THE NORTH AND EAST OF
KENTUCKY WHILE LOW PRESSURE IS FOUND OFF THE SOUTHEAST COAST. THIS
LOW HAS BEEN RESPONSIBLE FOR SOME VERY LIMITED MID AND HIGH LEVEL
CLOUDS SPREADING INTO KENTUCKY FROM THE SOUTHEAST. EXCEPT FOR
PERHAPS THE FAR EAST...AMPLE SUNSHINE DOMINATED EAST KENTUCKY
TODAY HELPING TO SEND TEMPERATURES UP INTO THE LOWER 80S FOR MOST
PLACES. DEWPOINTS FELL INTO THE LOWER 50S DUE TO SOME DRY AIR MIX
DOWN THIS AFTERNOON. WINDS...MEANWHILE...HAVE BEEN FROM THE
NORTHEAST AT 5 TO 10 KTS TODAY.
THE MODELS ARE IN GOOD AGREEMENT ALOFT...AS THEY HAVE BEEN FOR
MUCH OF THIS WEEK IN THE SHORT TERM. THEY ALL DEPICT AN UPPER
LOW...IN THE MIDST OF GENERAL HIGH HEIGHTS THROUGH MUCH OF THE
NATION...SLOWLY DEVELOPING OVER THE SOUTHEAST. THIS LOW WILL
CLOSE OFF AND DRIFT NORTHWEST WITH TIME...REACHING THE MID
TENNESSEE VALLEY BY 12Z SATURDAY. PLENTY OF ENERGY WILL SPIN
THROUGH THE HEART OF THIS LOW AS IT IMPACT OUR AREA LATER TONIGHT
AND THROUGH THE REST OF THE PERIOD. THE ECMWF IS A BIT STRONGER
WITH THIS LOW THAN THE OTHER MODELS WITH THE NAM12 IN THE MIDDLE
OF THE CONSENSUS. GIVEN THE GENERAL MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION NAM12 AND HRRR FOR WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE A DRY AND MOSTLY CLEAR EVENING
ACROSS EAST KENTUCKY. CLOUDS WILL MOVE IN FROM THE EAST AND
THICKEN DURING THE NIGHT WITH SHOWERS POTENTIALLY ARRIVING BEFORE
DAWN IN THE FAR EAST. THIS AREA OF PRECIPITATION WILL THEN BUILD
QUICKLY WEST THROUGH FRIDAY MORNING WITH MUCH OF THE CWA COVERED
BY MIDDAY. THE EXCEPTION COULD BE FAR NORTHERN PARTS OF EAST
KENTUCKY. SEVERAL ROUNDS OF SHOWERS ARE EXPECTED THROUGH THE AREA
INTO SATURDAY WITH A DRIFT TO THE NORTH ANTICIPATED FOR THE
DEEPER MOISTURE LATE IN THE PERIOD. POCKETS OF HEAVIER PCPN WILL
BE POSSIBLE...BUT IN GENERAL BETWEEN A QUARTER AND A HALF OF AN
INCH OF RAIN CAN BE EXPECTED FROM LATE TONIGHT THROUGH SATURDAY
MORNING. TEMPERATURES WILL BE MORE UNIFORM WITH THE RAIN FRIDAY
AND FRIDAY NIGHT...THOUGH THIS EVENING WE WILL STILL LIKELY SEE A
RIDGE TO VALLEY SPLIT DEVELOP BEFORE THE THICKER AND LOWER CLOUDS
MOVE IN FROM THE SOUTHEAST.
AGAIN USED THE SHORTBLEND INITIALLY FOR TEMPERATURES AND
DEWPOINTS...INTO THE FIRST PART OF THE DAY FRIDAY WITH THE
SUPERBLEND USED FROM THAT POINT THROUGH THE REST OF THE PERIOD.
DID MAKE SOME MINOR...TERRAIN BASED...ADJUSTMENTS TO THE
TEMPERATURES THIS EVENING. AS FOR POPS...ENDED UP SIMILAR TO A
BLEND OF THE MAV AND MET MOS THROUGH THE PERIOD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 343 PM EDT THU SEP 24 2015
UPPER LEVEL LOW THAT HAS BEEN SPINNING NEAR THE FAR SOUTHEAST WILL
SLOWLY RETROGRADE NORTHWEST THROUGH THE PERIOD. BEFORE EVENTUALLY
BECOMING DEFUSE BY EARLY NEXT WEEK. HOWEVER MODELS BECOME MUCH
MORE DIVERGENT THROUGH THE NEXT WEEK ESPECIALLY IN RELATION TO THE
SURFACE. AT THE SURFACE THE PERIOD BEGINS WITH HIGH PRESSURE
PARKED ACROSS NEW ENGLAND...MEAN WHILE A SURFACE TROUGH MOVES
ACROSS THE REGION. BETTER CHANCES OF PRECIP WILL BE EARLY ON SAT
WITH CHANCES WAINING THROUGH THE DAY. NOW STUCK CLOSER TO BLEND
OVERALL THROUGH THE LONG TERM PERIOD FOR CONSISTENCY...BUT MAY BE
A BIT OVERDONE WITH GFS SEEMING TO BE MORE EXAGGERATE PRECIP
THROUGH THE PERIOD COMPARED WITH ECMWF/CANADIAN. PERHAPS THE
BETTER DAY FOR PRECIP CHANCES WOULD BE AS WE MOVE INTO WED WITH
SOME TROUGHING AND LOWER HEIGHTS. THEN TRENDING DRIER OVERALL AS
WE MOVE INTO THURS. HAVE STUCK WITH RAIN SHOWERS AT THIS POINT
GIVEN THE TIME OF YEAR AND MODEL SOUNDINGS SHOWING MEAGER
INSTABILITY SIGNALS...HOWEVER BETTER CHANCES IF ANY OF THUNDER
WOULD BE MID WEEK. OVERALL TEMPS THROUGH THE PERIOD WILL REMAIN
NEARER NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 255 PM EDT THU SEP 24 2015
HIGH PRESSURE OFF TO OUR NORTH WILL KEEP VFR CONDITIONS THROUGH
THE REST OF THE DAY AND INTO THE NIGHT. BY LATE NIGHT...THOUGH...
AN UPPER LEVEL LOW WILL BEGIN TO IMPACT THE REGION...WITH
INCREASING MOISTURE IN THE FORM OF LOWERING CLOUDS AND POSSIBLY
SOME RAIN SHOWERS SEEPING IN FROM EAST TO WEST BETWEEN 09Z AND
12Z. DO EXPECT THE SHOWERS TO BECOME PREVAILING AT ALL THE SITES
BETWEEN 11Z AND 14Z WITH MVFR VIS AND POSSIBLY CIGS. WINDS WILL
GENERALLY REMAIN LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
340 PM EDT THU SEP 24 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 340 PM EDT THU SEP 24 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE TO THE NORTH AND EAST OF
KENTUCKY WHILE LOW PRESSURE IS FOUND OFF THE SOUTHEAST COAST. THIS
LOW HAS BEEN RESPONSIBLE FOR SOME VERY LIMITED MID AND HIGH LEVEL
CLOUDS SPREADING INTO KENTUCKY FROM THE SOUTHEAST. EXCEPT FOR
PERHAPS THE FAR EAST...AMPLE SUNSHINE DOMINATED EAST KENTUCKY
TODAY HELPING TO SEND TEMPERATURES UP INTO THE LOWER 80S FOR MOST
PLACES. DEWPOINTS FELL INTO THE LOWER 50S DUE TO SOME DRY AIR MIX
DOWN THIS AFTERNOON. WINDS...MEANWHILE...HAVE BEEN FROM THE
NORTHEAST AT 5 TO 10 KTS TODAY.
THE MODELS ARE IN GOOD AGREEMENT ALOFT...AS THEY HAVE BEEN FOR
MUCH OF THIS WEEK IN THE SHORT TERM. THEY ALL DEPICT AN UPPER
LOW...IN THE MIDST OF GENERAL HIGH HEIGHTS THROUGH MUCH OF THE
NATION...SLOWLY DEVELOPING OVER THE SOUTHEAST. THIS LOW WILL
CLOSE OFF AND DRIFT NORTHWEST WITH TIME...REACHING THE MID
TENNESSEE VALLEY BY 12Z SATURDAY. PLENTY OF ENERGY WILL SPIN
THROUGH THE HEART OF THIS LOW AS IT IMPACT OUR AREA LATER TONIGHT
AND THROUGH THE REST OF THE PERIOD. THE ECMWF IS A BIT STRONGER
WITH THIS LOW THAN THE OTHER MODELS WITH THE NAM12 IN THE MIDDLE
OF THE CONSENSUS. GIVEN THE GENERAL MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION NAM12 AND HRRR FOR WEATHER DETAILS.
SENSIBLE WEATHER WILL FEATURE A DRY AND MOSTLY CLEAR EVENING
ACROSS EAST KENTUCKY. CLOUDS WILL MOVE IN FROM THE EAST AND
THICKEN DURING THE NIGHT WITH SHOWERS POTENTIALLY ARRIVING BEFORE
DAWN IN THE FAR EAST. THIS AREA OF PRECIPITATION WILL THEN BUILD
QUICKLY WEST THROUGH FRIDAY MORNING WITH MUCH OF THE CWA COVERED
BY MIDDAY. THE EXCEPTION COULD BE FAR NORTHERN PARTS OF EAST
KENTUCKY. SEVERAL ROUNDS OF SHOWERS ARE EXPECTED THROUGH THE AREA
INTO SATURDAY WITH A DRIFT TO THE NORTH ANTICIPATED FOR THE
DEEPER MOISTURE LATE IN THE PERIOD. POCKETS OF HEAVIER PCPN WILL
BE POSSIBLE...BUT IN GENERAL BETWEEN A QUARTER AND A HALF OF AN
INCH OF RAIN CAN BE EXPECTED FROM LATE TONIGHT THROUGH SATURDAY
MORNING. TEMPERATURES WILL BE MORE UNIFORM WITH THE RAIN FRIDAY
AND FRIDAY NIGHT...THOUGH THIS EVENING WE WILL STILL LIKELY SEE A
RIDGE TO VALLEY SPLIT DEVELOP BEFORE THE THICKER AND LOWER CLOUDS
MOVE IN FROM THE SOUTHEAST.
AGAIN USED THE SHORTBLEND INITIALLY FOR TEMPERATURES AND
DEWPOINTS...INTO THE FIRST PART OF THE DAY FRIDAY WITH THE
SUPERBLEND USED FROM THAT POINT THROUGH THE REST OF THE PERIOD.
DID MAKE SOME MINOR...TERRAIN BASED...ADJUSTMENTS TO THE
TEMPERATURES THIS EVENING. AS FOR POPS...ENDED UP SIMILAR TO A
BLEND OF THE MAV AND MET MOS THROUGH THE PERIOD.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 232 AM EDT THU SEP 24 2015
AT THE START OF THE PERIOD...A STRONG SURFACE HIGH WILL RESIDE OVER
NEW ENGLAND...WITH AN UPPER LEVEL LOW MEANDERING NORTHWEST ACROSS
THE SOUTHEASTERN STATES. OVERALL WEAK STEERING FLOW WILL ALLOW THIS
DISTURBANCE TO SLOWLY WORK NORTHWARD ACROSS KENTUCKY WITH GOOD RAIN
CHANCES. PLENTY OF MOISTURE TO WORK WITH WITH DEEP FLOW OFF THE
ATLANTIC. ONLY NEGATIVE IS THE SOUTHEAST FLOW...WHICH TENDS TO DO A
NUMBER ON PRECIPITATION TRYING TO CROSS THE APPALACHIANS.
HOWEVER...GUIDANCE CONTINUES TO GO HIGHER WITH POPS AND WENT UPWARDS
ACCORDINGLY WITH THIS FORECAST ISSUANCE. WILL LEAVE THUNDER OUT AS
INSTABILITY WILL BE WEAK THIS TIME AROUND. RAIN CHANCES WITH THIS
SLOW MOVING SYSTEM WILL CONTINUE THROUGH SATURDAY AND PERHAPS EVEN
SUNDAY. THE WAVE WILL FINALLY GET PICKED UP BY THE NORTHERN JET LATE
SUNDAY WITH RAIN CHANCES ENDING. THIS MAY EVEN HAPPEN IN TIME FOR
THE TOTAL LUNAR ECLIPSE LATE SUNDAY...ALLOWING FOR SOME BREAKS IN
THE CLOUD COVER SUNDAY EVENING.
LOTS OF UNCERTAINTY IN THE FORECAST BEYOND SUNDAY AS THE 00Z GFS
KEEPS THE WEATHER ACTIVE THROUGH MUCH OF NEXT WEEK...WHILE THE 00Z
ECMWF PROVIDES ANOTHER MORE TRANQUIL STRETCH OF WEATHER. SURROUNDING
OFFICES HAVE MAINTAINED A MAINLY DRY FORECAST FOR NEXT WEEK...SO
WILL STAY THE COURSE FOR NOW AND AWAIT SOME BETTER MODEL AGREEMENT.
DID LEAVE A SLIGHT CHANCE OF RAIN IN THE FORECAST FOR WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 255 PM EDT THU SEP 24 2015
HIGH PRESSURE OFF TO OUR NORTH WILL KEEP VFR CONDITIONS THROUGH
THE REST OF THE DAY AND INTO THE NIGHT. BY LATE NIGHT...THOUGH...
AN UPPER LEVEL LOW WILL BEGIN TO IMPACT THE REGION...WITH
INCREASING MOISTURE IN THE FORM OF LOWERING CLOUDS AND POSSIBLY
SOME RAIN SHOWERS SEEPING IN FROM EAST TO WEST BETWEEN 09Z AND
12Z. DO EXPECT THE SHOWERS TO BECOME PREVAILING AT ALL THE SITES
BETWEEN 11Z AND 14Z WITH MVFR VIS AND POSSIBLY CIGS. WINDS WILL
GENERALLY REMAIN LIGHT AND VARIABLE THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
109 PM CDT THU SEP 24 2015
.DISCUSSION...
FOR 18Z TAF ISSUANCE.
&&
.AVIATION...
VIS IMAGERY/SFC OBS SHOW JUST SCT CU/CI COVERING THE AREA ATTM...
AND EXPECT THIS TREND TO CONTINUE AS FORECAST TIME-HEIGHT SECTIONS
AND SOUNDINGS INDICATE MOST MOISTURE REMAINING IN THESE LEVELS OF
THE ATMOSPHERE. DID REMOVE THE VCSH MENTION AT KBPT AS RADAR
TRENDS INDICATE THE COASTAL SHOWERS PUSHING SWD AWAY FROM THE
REGION...ALTHOUGH A SHOWER OR TWO COULD POP UP ANYWHERE THIS
AFTERNOON GIVEN DEEPENING MOISTURE NOTED IN REGIONAL 12Z
SOUNDINGS AND THE GENERAL WEAKNESS ALOFT SEEN IN WATER VAPOR
IMAGERY. WITH SFC DEWPOINTS INCREASING MAY HAVE TO LOOK AT
THROWING IN SOME RESTRICTIONS TO VISIBILITY FOR THE PRE- DAWN
HOURS LATER...OTHERWISE EXPECT VFR CONDITIONS TO CONTINUE.
SLIGHTLY ELEVATED ERLY WINDS ARE ALSO PROGGED TO PERSIST FOR THE
REMAINDER OF THE AFTERNOON AS THE GRADIENT REMAINS DECENT WITH
LOWER PRESSURES NOTED OVER THE SRN GULF.
25
&&
.PREV DISCUSSION... /ISSUED 1033 AM CDT THU SEP 24 2015/
UPDATE...SOME SHORT WAVE ENERGY INTO LOWER SE TX AND DEEPENING
MOISTURE OVER ACADIANA NOTED. WILL GO ALONG WITH HRRR AND INCLUDE
A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON.
MARINE...INCREASING GRADIENT FROM THE NORTHEAST OVER THE EASTERN
OUTER WATERS. ADDED CAUTION FOR THOSE WATERS EAST OF INTRACOASTAL
CITY THROUGH THIS AFTERNOON.
SWEENEY
PREV DISCUSSION... /ISSUED 614 AM CDT THU SEP 24 2015/
AVIATION... HIGH PRESSURE CONTINUES TO LOSE ITS GRIP OVER THE
REGION WITH PRECIPITABLE WATER VALUES HEADING UPWARD. WITH
THAT...RADAR SHOWING SHOWERS OVER THE NEAR COASTAL WATERS.
EXPECTING BULK OF CONVECTION TODAY TO REMAIN OVER THE NEAR
COASTAL WATERS...BUT COULD SEE SOME DEVELOPMENT IN THE VICINITY
OF THE BPT TERMINAL. CARRYING VCSH THERE. OTHERWISE...VFR EXPECTED
WHILE WINDS REMAIN LIGHT.
23
PREV DISCUSSION... /ISSUED 505 AM CDT THU SEP 24 2015/
DISCUSSION...
VERY QUIET PATTERN ACROSS THE SOUTHERN STATES AS HIGH PRESSURE
REMAINS IN CONTROL. A FEW SHOWERS NOTED ON RADAR GENERALLY FROM 20
TO BEYOND 60 NM SOUTH OF THE COAST. SHOWERS ARE MOVING WESTWARD.
MOISTURE HAS BEEN SLIPPING BACK INTO THE NW GULF REGION OVER THE
LAST DAY OR TWO AS DEW POINTS ARE NOW HOLDING IN THE UPPER 60S
ALONG THE I-10 CORRIDOR AND MID 60 ACROSS THE LAKES REGION OF SE
TX AND CNTRL LA THIS MRNG.
ALOFT THE RIDGE WILL REMAIN IN PLACE OVER THE NEXT SEVERAL DAYS
BEFORE BEGINNING TO BREAK OVER THE WEEKEND. THIS WILL ALLOW BETTER
SHOWER DEVELOPMENT ON SUNDAY INTO MONDAY. TEMPERATURES WILL BE
RUNNING NEAR NORMAL DURING THE DAY "AROUND 90" AND A BIT WARMER
DURING THE OVERNIGHT HOURS "AROUND 70 DEGREES". THEREFORE WE ARE
NOT LOOKING FOR A BIG CHANGE FOR THE ATMOSPHERE.
TOWARDS THE BEGINNING OF NEXT WEEK LOOKING TO SEE A SURFACE LOW
TO MOVE OFF OF THE YUCATAN PENINSULA NORTHWARD INTO EASTERN LA
AND SOUTHERN MISSISSIPPI TOWARDS TUESDAY. AS A RESULT RAIN
CHANCES WILL BE LIMITED OVER OUR REGION.
19
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 91 67 91 65 / 20 10 10 10
LCH 90 70 90 70 / 20 10 20 10
LFT 90 70 89 68 / 20 10 20 10
BPT 89 70 91 70 / 20 10 20 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION UNTIL 7 PM CDT THIS EVENING FOR
GMZ475.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
329 PM CDT THU SEP 24 2015
.SYNOPSIS...
ISSUED AT 329 PM CDT THU SEP 24 2015
H5 ANALYSIS THIS MORNING HAD A POSITIVE TILTED RIDGE
EXTENDING FROM SOUTHERN CALIFORNIA INTO THE NORTHERN ROCKIES.
DOWNSTREAM OF THE RIDGE...A CLOSED LOW WAS NOTED OVER NERN NEBRASKA
THIS MORNING...WITH A SECONDARY LOW OVER THE TEXAS PANHANDLE. BASED
ON CURRENT SATELLITE IMAGERY...THE NORTHERN MOST UPPER LEVEL LOW
WAS JUST WEST OF NORFOLK NEBRASKA. LIGHT RAIN SHOWERS IN ASSOCIATION
WITH THE LOW...HAVE TRACKED FROM NORTH TO SOUTH ALONG HIGHWAY 281
FROM SPENCER TO BARTLETT THIS MORNING...AND HAVE SINCE DISSIPATED IN
COVERAGE THIS AFTN. FURTHER WEST OF THE LOW....A BROAD SHIELD OF
CLOUDINESS EXTENDED WEST TO THE NEBRASKA PANHANDLE WITH A MIXTURE OF
LOW TO MID CLOUDS PRESENT. OVER THE PAST 1 TO 2 HRS...THE WESTERN
EDGE OF THIS CLOUD COVER HAS BEGUN TO BURN OFF WITH CLEARING NOTED
OVER PORTIONS OF THE EASTERN NEBRASKA PANHANDLE AND SWRN NEBRASKA.
AT THE SURFACE...LOW PRESSURE WAS NOTED OVER NORFOLK NEBRASKA WITH A
SURFACE TROUGH EXTENDING SSW INTO CENTRAL AND SWRN KS. WEST OF THE
TROUGH NORTHWESTERLY WINDS WERE PRESENT FROM WEST OF THE LOW TO THE
PANHANDLE. ACROSS THE PANHANDLE...WINDS WERE LIGHTER FROM THE NORTH
OR WEST. TEMPERATURES AS OF 3 PM CDT...RANGED FROM 65 AT AINSWORTH TO
77 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 329 PM CDT THU SEP 24 2015
MAIN FORECAST CONCERNS OVER THE SHORT TERM...THROUGH FRIDAY
AFTERNOON...ARE PRECIPITATION AND FOG. STRONG LOW PRESSURE CENTER
CONTINUES TO SIT OVER CENTRAL AND EASTERN NEBRASKA...AND MAY
RETROGRADE A LITTLE ON FRIDAY.
FOR THE REMAINDER OF THURSDAY AFTERNOON AND EVENING...KEPT ISO/SCT
POPS ACROSS NORTH CENTRAL NEBRASKA AS BANDS OF WEAK RAIN ROTATE
SOUTH/SOUTHEAST ALONG THE BACKSIDE OF THE SURFACE LOW. LOWERED QPF
AS MOST OF THE PRECIPITATION WAS BEING RECORDED AS DRIZZLE BY 20Z.
THE TRICKY PART IS HOW FAR WEST THE THICK STRATUS WILL STRETCH THIS
EVENING. THE PANHANDLE HAS STAYED CLEAR FOR MOST OF THE DAY AND
BREAKS IN THE COVER HAVE COME AND GONE ALONG THE HIGHWAY 83
CORRIDOR.
OVERNIGHT INTO FRIDAY MORNING...THINKING THE STRATUS WILL BEGIN TO
EXPAND WESTWARD BY 25/06Z AS THE SURFACE LOW TREKS SOUTHWEST. NAM
FORECAST SOUNDINGS SHOW A 5KFT SATURATED LAYER NEAR THE SURFACE IN
THE EASTERN PORTIONS OF THE FORECAST AREA...ABOUT 2KFT THICK FROM
KLBF TO KVTN...AND RELATIVELY SHALLOW IN THE PANHANDLE. THE NAM ALSO
INDICATES SOME LIFT AND SATURATION AT THE 300K SURFACE IN THE
EASTERN HALF OF THE FORECAST AREA...SO INTRODUCED DRIZZLE BEGINNING
09Z FRIDAY. FARTHER WEST...THE RUC AND GFS WERE AGREEING WITH
SATURATION IN THE NEAR SURFACE LAYER. MENTIONED PATCHY FOG FOR THE
ENTIRE FORECAST AREA...BUT THINKING THE WESTERN HALF WILL LIKELY
EXPERIENCE MORE FOG WHILE EASTERN HALF HAS MORE DRIZZLE AND STRATUS.
FOG WILL LIKELY BE MORE WIDESPREAD ALONG THE EDGE OF THE
STRATUS...SO UPGRADED TO AREAS OF FOG BETWEEN THE PANHANDLE AND
HIGHWAY 83. SURFACE WIND PROFILES WILL ALSO BE MORE FAVORABLE TOWARD
FOG FARTHER WEST...AS SPEEDS STAY NEAR 10 MPH WHERE DRIZZLE IS
MENTIONED. SOME FOG MAY BE LOCALLY DENSE...BUT AM NOT CONFIDENT ON
COVERAGE DUE TO WIND.
FRIDAY AFTERNOON...CONTINUED PATCHY DRIZZLE FOR THE EASTERN HALF OF
THE FORECAST AREA AS SURFACE WINDS TURN EAST AND ADVECT IN MOIST
AIR. FORECAST SOUNDINGS KEEP THE LOW LEVELS NEARLY SATURATED...SO
ANY BIT OF LIFT COULD RESULT IN SOME LIGHT PRECIPITATION.
TEMPERATURE WISE...LOWERED MIN TEMPS TONIGHT ACROSS THE PANHANDLE
FOR MOSTLY CLEAR CONDITIONS AND LIGHT NORTH WINDS. LATEST GUIDANCE
HAS LOWER TO MID 40S IN THE WESTERN SANDHILLS...BUT GENERALLY DID
NOT GO THAT LOW. BUMPED UP A DEGREE ACROSS NORTH CENTRAL NEBRASKA
DUE TO PERSISTENT STRATUS AND HIGHER DEW POINTS. CLOUD COVER WILL
LIKELY LEAD TO A LARGE GRADIENT IN MAX TEMPS ACROSS THE FORECAST
AREA FRIDAY. THE EASTERN PANHANDLE WILL LIKELY REMAIN UNDER FAIR
SKIES...ALLOWING TEMPERATURES TO REACH THE UPPER 70S AND LOWER 80S.
UNDER THE STRATUS IN THE EAST...LIMITED HIGHS TO THE LOWER 70S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 329 PM CDT THU SEP 24 2015
FRIDAY NIGHT THROUGH SUNDAY...THE MAIN FORECAST CHALLENGES IN THE
MID RANGE IS FOG POTENTIAL FRIDAY NIGHT...THEN TEMPERATURES. FOR
FRIDAY EVENING...THE UPPER LEVEL LOW AND SURFACE LOW WILL DRIFT TO
THE SOUTH SOUTHWEST INTO NORTHERN KANSAS. A WEAK SHORTWAVE WILL
ROTATE ON THE NORTHWESTERN PERIPHERY OF THE LOW LATE FRIDAY
AFTERNOON AND FRIDAY EVENING. ENOUGH WEAK FORCING IS PRESENT TO
FACILITATE LOW POPS IN THESE AREAS FRIDAY EVENING. HOWEVER...THE
MOIST LAYER IS FAIRLY SHALLOW FRIDAY EVENING AND FRIDAY NIGHT...SO
THINKING HERE IS MORE OF A DRIZZLE SETUP FRIDAY
EVENING...PARTICULARLY WITH DRYING ALOFT AND WEAK LIFT NOTED IN THE
SATURATED LOW LAYER. AFTER LATE EVENING...THE THREAT FOR FOG WILL
INCREASE OVERNIGHT AS LIGHT EASTERLY WINDS PERSIST ALONG WITH A VERY
MOIST BOUNDARY LAYER. ATTM...THE MAIN AREA OF CONCERN FOR FOG IS
WEST OF HIGHWAY 183. EAST OF THIS ROUTE...BUFKIT SOUNDINGS ARE MORE
INDICATIVE OF STRATUS AS THE BOUNDARY LAYER IS SOMEWHAT DRIER. ON
SATURDAY...THE REMNANTS OF THE LOW WILL FILL IN OVER SRN KS AS A
POSITIVELY TILTED RIDGE BUILDS INTO NORTHERN NEBRASKA. SRLY WINDS
WILL INCREASE IN THE AFTERNOON...PARTICULARLY IN THE WEST AS SURFACE
LOW PRESSURE DEEPENS OVER NERN WYOMING. INCREASED SRLY WINDS...WILL
ALLOW CLOUDINESS TO DISPERSE BY MIDDAY SAT ALLOWING HIGHS TO REACH
THE UPPER 70S AND LOWER 80S. FOR SATURDAY NIGHT...LOW LEVEL MOISTURE
WILL REMAIN PREVALENT ACROSS WESTERN AND NORTH CENTRAL NEBRASKA WITH
OVERNIGHT DEW POINTS IN THE MID AND UPPER 50S. EVEN WITH DECENT BL
MOISTURE PRESENT SAT NIGHT...AM NOT TOO CONCERNED ABOUT FOG ATTM
WITH SRLY WINDS OF 10 TO 15 MPH EXPECTED OVERNIGHT. THE COMBINATION
OF WIND AND LOW LEVEL MOISTURE...WILL LEAD TO A MILD NIGHT WITH LOWS
IN THE 50S TO AROUND 60. ON SUNDAY...LOW PRESSURE WILL DROP
SOUTHEAST INTO THE WESTERN PANHANDLE. SOUTHWESTERLY WINDS WILL
INCREASE FURTHER ON SUNDAY AS MUCH WARMER H85 AIR PUSHES INTO THE
PANHANDLE AND WESTERN HALF OF THE CWA. INCREASED HIGHS INTO THE
UPPER 80S IN THE WEST...AND WOULDN/T BE SURPRISED IF WE SEE A 90+
TEMP IN THE EASTERN PANHANDLE OR FAR SW SUNDAY AFTERNOON GIVEN THE
FCST H85 TEMPS OF 25 TO 29C.
SUNDAY NIGHT THROUGH THURSDAY...MAINLY DRY CONDS WILL CONTINUE INTO
MONDAY WITH HIGHS MAINLY IN THE 80S TO LOWER 90S. A PACIFIC COOL
FRONT WILL PUSH INTO THE FORECAST AREA ON MONDAY NIGHT...STALLING
OVER SRN NEBRASKA ON TUESDAY. MID LEVEL FRONTOGENESIS WILL INCREASE
OVER CENTRAL AND NORTHERN NEBRASKA TUESDAY/TUESDAY NIGHT WITH THE
THREAT FOR SHOWERS/TSRAS CONTINUED. BEYOND TUESDAY NIGHT...THE ECMWF
AND GFS DIVERGE SIGNIFICANTLY IN THEIR SOLUTIONS. THE ECMWF BUILDS A
RIDGE INTO THE CENTRAL CONUS WEDS/THURSDAY...WHICH WOULD LEAD TO DRY
AND VERY WARM TEMPERATURES. THE 12Z GFS THIS MORNING HAS A LESS
AMPLIFIED SOLUTION ACROSS THE CENTRAL CONUS WITH FAVORABLE JET
DYNAMICS FOR PRECIPITATION WEDS THROUGH THURSDAY. INHERITED FCST HAD
A MENTION OF PRECIPITATION WEDS-THUS. GIVEN THE MODEL
DIFFERENCES...WILL LEAVE IN MENTION OF PCPN TO MAINTAIN A CONSISTENT
FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1231 PM CDT THU SEP 24 2015
MVFR CEILINGS WILL CONTINUE ACROSS MUCH OF WESTERN NEBRASKA
THROUGH THIS EVENING AS A CENTER OF LOW PRESSURE SITS OVER
NORTHEAST NEBRASKA. BREAKS IN THE STRATUS DECK WILL RAISE CEILINGS
TEMPORARILY...MAINLY ACROSS THE PANHANDLE AND SOUTHWEST
NEBRASKA...INCLUDING KLBF. OVERNIGHT...THE WINDS WILL LIGHTEN
ALLOWING FOG OR STRATUS TO REDEVELOP. MVFR OR IFR CEILINGS
CONDITIONS ARE LIKELY FROM 25/09Z TO 25/15Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...DS
LONG TERM...CLB
AVIATION...DS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1250 PM CDT THU SEP 24 2015
.UPDATE...
ISSUED AT 1250 PM CDT THU SEP 24 2015
THE MAIN CHANGES MADE TO THE FORECAST WAS CLOUD COVER...OTHERWISE
THE FORECAST IS ON TRACK.
UPDATE ISSUED AT 938 AM CDT THU SEP 24 2015
POPS WERE SLIGHTLY ADJUSTED TO THE RADAR...OTHERWISE THE FORECAST
IN ON TRACK.
UPDATE ISSUED AT 625 AM CDT THU SEP 24 2015
GIVEN WEBCAM TRENDS THROUGH 1120 UTC...EXPANDED THE DENSE FOG
ADVISORY INTO THE SOURIS BASIN. FLOOD ADVISORIES ACROSS THE BASIN
WERE ALSO EXTENDED THROUGH 1630-1700 UTC TODAY TO ASSESS ANY FLOOD
IMPACTS FROM HEAVY RAINFALL OVERNIGHT.
UPDATE ISSUED AT 319 AM CDT THU SEP 24 2015
A DENSE FOG ADVISORY WILL BE ISSUED FOR PORTIONS OF SOUTH CENTRAL
NORTH DAKOTA INCLUDING THE JAMES RIVER VALLEY. WEBCAMS AND SURFACE
OBSERVATIONS SUPPORT AN ADVISORY AND THE HRRR VISIBILITY FORECAST
MAINTAINS LESS THAN ONE HALF MILE THROUGH THE MORNING. THIS
ADVISORY MAY NEED TO BE EXTENDED WEST AND NORTH AT SOME POINT
LATER THIS MORNING. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 149 AM CDT THU SEP 24 2015
LATEST WATER VAPOR IMAGERY SHOWS A DISTINCT SHORTWAVE NEAR
SHERWOOD MOVING EAST WITH TIME. A CONTINUOUS BAND OF SHOWERS AND
THUNDERSTORMS HAS PROMPTED THE ISSUANCE OF A FEW AREAL FLOOD
ADVISORIES ACROSS NORTH CENTRAL NORTH DAKOTA THROUGH 0600 AM CDT.
EXPECT THE PRECIPITATION AREA TO GRADUALLY SHIFT EAST AND EXIT
THE TURTLE MOUNTAINS BETWEEN 15Z-17Z THURSDAY.
OTHERWISE...STRATUS AND POTENTIALLY WIDESPREAD DENSE FOG TAKE
CONTROL OVER THE REST OF THE FORECAST AREA THROUGH THE MORNING
HOURS. THE RAP13/HRRR/NAM REMAIN PERSISTENT IN DEVELOPING LOW
VISIBILITIES/LESS THAN ONE HALF MILE...AND CLOUDS BETWEEN 200FT
AND 1000FT THROUGH 18Z THURSDAY. CLOUDS HAVE BEEN LOWERING HERE
AT BISMARCK...AS WELL AS OTHER SURROUNDING SURFACE OBSERVATIONAL
SITES WHICH FURTHER SUPPORT THE STRATUS AND FOG. MAY BE ISSUING A
DENSE FOG ADVISORY AT SOME POINT AFTER THIS DISCUSSION IS
DISSEMINATED. MID/UPPER LEVEL RIDGE BEGINS TO BUILD NORTHEAST
THURSDAY AFTERNOON AS HEIGHTS RISE FROM SOUTHWEST TO NORTHEAST.
DECREASING CLOUDS WITH AMPLE SUNSHINE RETURN DURING THE AFTERNOON
HOURS. HIGHS IN THE 70S TODAY WITH 80F IN THE FAR WEST.
ALTHOUGH DRYING AND WARMING CONDITIONS COMMENCE LATER TODAY...NAM
BUFKIT SOUNDINGS AND TO SOME EXTENT THE GFS SHOW A SHALLOW LAYER
OF LOW CLOUDS/FOG AGAIN DEVELOPING OVER SOUTH CENTRAL...KBIS/KJMS
AFTER MIDNIGHT THURSDAY INTO EARLY FRIDAY MORNING. THIS IS DUE TO
A WEAK BUT PERSISTENT LOW LEVEL EAST TO SOUTHEAST WIND.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 149 AM CDT THU SEP 24 2015
A WARM UP INTO SATURDAY FOLLOWED BY A COOL DOWN EARLY NEXT WEEK
HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD
AGREEMENT ON AN AMPLIFYING UPPER LEVEL RIDGE FROM THE SOUTHWEST US
INTO THE NORTHERN PLAINS THURSDAY INTO FRIDAY. THIS RIDGE IS
FORECAST TO BREAK DOWN BY SUNDAY...WITH A POTENTIAL BROAD UPPER
LEVEL TROUGH DEVELOPING ACROSS THE REGION EARLY NEXT WEEK.
THUS...TEMPERATURES ARE FORECAST TO WARM INTO SATURDAY...WITH
WIDESPREAD HIGHS IN THE 80S POSSIBLE SATURDAY AHEAD OF A STRONG
COLD FRONT FORECAST TO PROPAGATE ACROSS THE STATE SATURDAY NIGHT
INTO SUNDAY. THEREAFTER...A RETURN TO COOLER BUT STILL NEAR
NORMAL HIGHS IN THE 60S ARE EXPECTED NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1250 PM CDT THU SEP 24 2015
IFR/MVFR CEILINGS WILL LIFT FROM WEST TO EAST THROUGH THE
AFTERNOON. VLIFR CONDITIONS AT KJMS ARE EXPECTED TO PERSIST UNTIL
20Z. LIGHT WINDS AT KBIS AND KJMS MAY LEAD TO EARLY MORNING
DEVELOPMENT OF FOG WITH MVFR CIGS/VSBYS POSSIBLE. THOUGH
UNCERTAINTY REMAINS THIS FAR OUT...HAVE OPTED TO MENTIONED VCFG
AND SCT CLOUDS AT 500FT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AC
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AC
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
535 PM EDT THU SEP 24 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE NEAR THE ATLANTIC COASTLINE WILL FEED
MOISTURE-RICH AIR INTO THE REGION THROUGH MOST OF THE WEEKEND...
RESULTING IN A LENGTHY STRETCH OF WIDESPREAD LIGHT TO MODERATE
RAINFALL. DRIER CONDITIONS WILL PREVAIL HEADING INTO LATE SUNDAY AND
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 530 PM...LATEST SATELLITE LOOP SHOWS A BAND OF DEEP CONVECTION
OFF THE CENTRAL SC SHORE...DRIFTING NORTHWARD. A BAND OF COLDER
CLOUD TOPS HAS PIVOTED BACK TOWARD THE COAST...RESULTING IN WARMING
CLOUD TEMPERATURES ACROSS THE MIDLANDS OF SC AND CENTRAL GA. BASED
ON THE SATELLITE TRENDS...THE CURRENT BAND OF LIGHT RAINFALL MAY
SLIDE TOWARD THE WEST...FOLLOWED BY CLUSTERS OF LIGHT RAIN HEADED
INTO THIS EVENING.
THE ENVIRONMENT BECOMES MORE DYNAMIC LATER THIS EVENING AND
OVERNIGHT. NAM AND RAP FORECAST SOUNDINGS INDICATE A DEEP LAYER OF
EAST LLVL FLOW ACROSS THE WESTERN CAROLINAS. PWS WILL INCREASE TO
NEARLY 2 INCHES WITH THE WARM CLOUD LAYER DEEPENING TO AROUND 13
KFT. IN ADDITION...GFS40S SHOWS A FIELD OF Q-VECTOR CONVERGENCE
DEVELOPING ACROSS THE CWA... ON THE NE SIDE OF A CLOSED MID LEVEL
LOW.
I WILL UPDATE THE FORECAST TO ADJUST POP TIMING AND INCREASE QPF
ACROSS THE UPSLOPE AREAS.
AT 230 PM EDT THURSDAY...AN UPPER LOW OVER THE SE AND AND ASSOCIATED
SURFACE LOW OVER OFF THE GA COAST WILL CONTINUE TO SEND MOISTURE
INLAND TOWARD THE BLUE RIDGE TONIGHT AND FRIDAY. THE COMBINATION OF
DIFFLUENT FLOW ALOFT...INCREASING EASTERLY LOW LEVEL UPSLOPE
FLOW...INCREASING EASTERLY ISENTROPIC UPGLIDE OVER A SURFACE
RIDGE...AND MOISTURE WELL ABOVE NORMAL...WILL FAVOR THE DEVELOPMENT
OF HEAVY PRECIPITATION ALONG THE EAST FACING BLUE RIDGE. ALTHOUGH
MUCH OF THE AREA IS CURRENTLY IN DROUGHT...LOCALIZED FLOODING COULD
OCCUR IN SMALLER STREAM BASIN AND HILLY TERRAIN. A FLASH FLOOD WATCH
WILL BE NOT ISSUED OUR BLUE RIDGE AREA...AS IT APPEARS PRECIPITANT
WILL GRADUALLY SPREAD NE FROM THE UPPER SAVANNAH RIVER VALLEY TO THE
NC MOUNTAINS. TEMPERATURES WILL RUN BELOW NORMAL IN COOL NE SURFACE
FLOW...ESPECIALLY MAXIMUMS UNDER CLOUD COVER.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 255 PM THURSDAY...ALTHOUGH GUIDANCE CONTINUES TO SHOW
WIDESPREAD RAIN AT THE START OF THE PERIOD THEN GRADUALLY
DIMINISHING IN COVERAGE BY THE END OF THE PERIOD...THEY HAVE BACKED
OFF ON AMOUNT OF QPF. MANY OF THE TRADITIONAL PARAMETERS NEEDED FOR
FLOODING TYPE RAINFALL ARE NOT THERE. OPS MDLS SHOW PW VALUES ARE UP
TO 190 PERCENT OF NORMAL...BUT THE ENSEMBLE GUIDANCE SHOWS 1 TO MAYBE
1.5 STANDARD DEVIATIONS ABOVE NORMAL. WHILE THERE IS SOME UPPER
DIVERGENCE ASSOCIATED WITH THE UPPER JET MAX...1 STD DEVIATION ABOVE
NORMAL...THIS DISSIPATES ON SAT AS THE JET MOVES OUT OF THE AREA.
THE MAIN FORCING WILL COME FROM STRONG UPSLOPE FLOW WITH THE
ENSEMBLE GUIDANCE SHOWING H85 ELY FLOW UP TO 4 STD DEVIATIONS ABOVE
NORMAL. THERE WILL ALSO BE STRONG ISENTROPIC LIFT IN THE VERY MOIST
LOW LEVELS. THE ENSEMBLE GUIDANCE CONTINUES TO SHOW A NORTHWARD
SHIFT IN THE BEST H85 FLOW THRU THE PERIOD...ALTHOUGH THE SREF DOES
KEEP IT OVER OUR PORTION OF THE BLUE RIDGE LONGER THAN THE GEFS.
GIVEN THESE FACTORS...WPC HAS DROPPED THE QPF FCST ACROSS THE AREA.
HAVE FOLLOWED THESE TRENDS AS WELL. THAT SAID...THIS STILL PUTS 1 TO
3 INCHES OF RAIN ACROSS AND NEAR THE NRN BLUE RIDGE...SO WILL HAVE
TO KEEP AN EYE ON THE RAINFALL AMOUNTS. CANNOT RULE OUT FLOODING...
BUT IT APPEARS TO NOT BE WIDESPREAD AND WARRANT A WATCH AT THIS
TIME. HIGHEST POPS WILL BE ALONG AND NEAR THE BLUE RIDGE THRU THE
PERIOD...WITH LOWER POP ACROSS THE SWRN CWFA.
WITH A WEDGE PATTERN IN PLACE AND CONTINUED RAINFALL...EXPECT BREEZY
AND COOL CONDITIONS EACH DAY. HIGHS WILL BE NEARLY 10 DEGREES BELOW
NORMAL ON SAT THEN RISE A COUPLE OF DEGREES SUN. LOWS WILL BE ABOUT
5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 230PM THURSDAY...THE EXTENDED PERIOD BEGINS ON SUNDAY NIGHT
WITH THE WEEKEND RAINFALL EVENT ON THE WANE AND DRIER CONDITIONS
BUILDING IN ACROSS THE FORECAST AREA. WHILE FLOW ALOFT WILL BE
SOUTHERLY THANKS TO A CUT-OFF 500MB LOW OVER SOUTH TEXAS AND AN
ANTICYCLONE OVER THE WESTERN SARGASSO SEA...SURFACE HIGH PRESSURE
AND A LACK OF NOTABLE SHORTWAVES IN THE FLOW ALOFT SHOULD KEEP THE
AREA MOSTLY DRY THROUGH MIDDAY TUESDAY.
THEREAFTER...THERE IS GENERAL AGREEMENT THAT A LONGWAVE TROUGH WILL
MOVE ACROSS THE NORTHERN HALF OF THE U.S. AND CANADA AND AN
ASSOCIATED SURFACE LOW PRESSURE SYSTEM AND ATTENDANT COLD FRONT WILL
APPROACH OUR AREA ON WEDNESDAY. BOTH THE GFS AND THE ECMWF ARE NOT
EXCITED ABOUT NOTABLE RAINFALL AS A RESULT OF THE FRONTAL
PASSAGE...HOWEVER...THE GFS CONTINUES TO BE BULLISH ON A MODEST BUT
WELL-DEFINED SURFACE LOW MOVING NORTHWARD OVER THE CENTRAL GULF AND
APPROACHING THE LOUISIANA COAST BY TUESDAY AFTERNOON. THE ECMWF
WEAKENS THE LOW TO AN OPEN TROUGH OVER THE NORTHERN GULF. BOTH
MODELS DO NOT BRING THE FEATURE INLAND...HOWEVER THE GFS KEEPS THE
SOUTHERN APPALACHIANS IN A MOISTURE-RICH ENVIRONMENT WITH A TROPICAL
CONNECTION TO THE CARIBBEAN AND EJECTS ROUNDS OR BANDS OF CONVECTIVE
PRECIP NORTH FROM THE GULF LOW ACROSS THE DEEP SOUTH AND INTO OUR
AREA BEGINNING TUESDAY EVENING AND LASTING THROUGH WEDNESDAY. THE
ECMWF PERSISTS WITH WEAK NORTHEASTERLY FLOW ACROSS MUCH OF THE
SOUTHEAST HEADING INTO THURSDAY. AT THIS TIME THE FORECAST MAINTAINS
SLIGHT CHANCE TO CHANCE POPS DURING THE MID-WEEK PERIOD GIVEN THE
DECENT MOISTURE THAT REMAINS IN PLACE FOLLOWING THE EVENT ENDING ON
SUNDAY...THE ANTICIPATED FRONTAL PASSAGE...AND THE PERSISTENCE OF
BOTH MODELS OVER THE PAST FEW RUNS OF SUGGESTING SOME ACTIVITY IN
THE GULF MOVING TOWARDS THE COAST. NEVERTHELESS...BOTH THE ECMWF AND
GFS AGREE THAT A STRONG 1028MB SURFACE HIGH BUILDS IN ACROSS THE
NORTHEAST U.S. ON THE CONFLUENT SIDE OF THE UPPER-LEVEL LONGWAVE
TROUGH AND WEDGES DOWN ACROSS MUCH OF THE SOUTHEAST U.S....
SIGNIFICANTLY DRYING US OUT THROUGH THE END OF THE PERIOD ON FRIDAY
MORNING.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MOISTURE WILL CONTINUE TO INCREASE...WITH CEILINGS FALLING
TO TO IFR BY DAYBREAK...AND POSSIBLE REMAINING THERE AS INCREASING
RAINFALL MOISTENS THE LOWERS LAYER OF THE ATMOSPHERE. VSBY MAY LOWER
TO IFR BY DAWN IN HEAVIER SHOWERS. WINDS WILL FAVOR THE NE...WITH
SOME POTENTIAL FOR GUSTS TO STAY UP OVERNIGHT.
ELSEWHERE...EASTERLY FLOW ALOFT WILL BRING ATLANTIC MOISTURE UP
AGAINST THE BLUE RIDGE...FAVORING DECREASING CEILINGS. BY DAWN IFR
CIGS ARE EXPECTED...POSSIBLY LOWER AT KAVL. DAYBREAK IFR VSBYS ARE
POSSIBLE IN HEAVIER SHOWERS. IFR CIGS CONDITIONS MAY PERSIST THROUGH
THE MORNING AS INCREASING RAIN KEEPS THE LOWEST LAYERS MOIST. WINDS
WILL FAVOR THE NE...EXCEPT AT KAVL WHERE WINDS WILL VEER FROM NW AND
CHANNEL DOWNVALLEY FORM THE SE. GUSTS COULD PERSIST OVERNIGHT.
OUTLOOK...DEEP MOISTURE AND WIDESPREAD LIFT WILL LIKELY RESULT IN
RESTRICTIVE CEILINGS AND VISIBILITY PERIODICALLY THRU SATURDAY. IN
ADDITION...RAINFALL WILL BE MODERATE TO HEAVY AT TIMES...ESPECIALLY
FRIDAY AND FRIDAY NIGHT.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 85% HIGH 83% HIGH 92%
KGSP HIGH 91% MED 73% HIGH 83% MED 75%
KAVL HIGH 100% HIGH 89% HIGH 81% HIGH 95%
KHKY HIGH 100% HIGH 92% MED 73% HIGH 92%
KGMU HIGH 91% HIGH 91% MED 77% MED 75%
KAND MED 76% LOW 37% MED 69% MED 67%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JMP
NEAR TERM...NED
SHORT TERM...RWH
LONG TERM...JMP
AVIATION...JAT
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1233 PM CDT THU SEP 24 2015
.UPDATE...
A compact shortwave trough continues to dive southeast across the
High Plains. Per the water vapor loop, this wave is currently
located along the TX/NM border south of Clovis. Diurnal showers
and thunderstorms will be possible downstream and beneath this
feature this afternoon. Convection has already developed over much
of the south Plains and is expected to affect the western portions
of the Big Country and Concho Valley. Instability is somewhat
limited over west central TX, but it should be adequate to support
weak, disorganized updrafts. Isolated showers and thunderstorms
were added to the forecast, generally along/west of a line from
Haskell, to San Angelo, to Ozona. Otherwise, changes to the
inherited forecast were minimal.
&&
.AVIATION...
/18Z TAFS/
Light southerly winds will veer to the east across the area this
afternoon, generally remaining under 10 kts. After sunset, winds
will go light and variable, remaining so through 18z Friday.
Isolated showers and thunderstorms will be possible this
afternoon, mainly west of a KABI-KSJT line. Given the very limited
coverage across west central TX, no mention will be carried in the
current TAF package. Expect VFR conditions through the period.
&&
.PREV DISCUSSION... /ISSUED 607 AM CDT THU SEP 24 2015/
AVIATION...
/|12Z TAFS/
VFR next 24 hours. South winds less than 10 KTS will become
east this afternoon.
PREV DISCUSSION... /ISSUED 404 AM CDT THU SEP 24 2015/
SHORT TERM...
(Today and Tonight)
Upper low along the Texas Panhandle and New Mexico state line is
expected move slowly south today and tonight. West Central Texas,
however, will be under the influence of an upper level ridge,
keeping the region for the most part, dry.
The HRRR and Texas Tech WRF short range models do develop
isolated showers in extreme western sections of West Central
Texas....west of a Sweetwater to San Angelo to Sonora line today.
With dry air at the surface, however, showers that develop should
mainly be virga, so will leave out mention of rain. With more
mid/upper level clouds, highs today should be in the lower 90s. It
will be cooler tonight with lows in the lower and mid 60s, due to
light winds and dry air.
LONG TERM...
(Friday through next Wednesday)
Currently, an upper level low is slowly moving south through
eastern New Mexico, causing the ridge over our area to weaken.
Another more pronounced low is located over northeastern Nebraska.
Both of these features are expected to move south through our
area between now and Saturday. The first, weaker wave will move
through tomorrow, with the second one in Nebraska, moving through
Saturday. Models don`t completely agree on exact path, strength,
or timing of the feature Saturday. However, with the ridge
weakened, and the shortwave moving through, it was enough to
introduce low end slight chance PoPs across our western counties
on Saturday. While we will have a chance for precipitation, we are
not expecting widespread coverage or heavy rainfall.
Along with the rain chances on Saturday, we will see cooler
temperatures both Friday and Saturday under the weakened ridge.
An upper level low will remain nearly stationary over southern
Texas from Saturday night into early next week, but isn`t expected
to result in any precipitation in our area. By Monday, a gradual
warm-up is expected to begin as the ridge re-establishes itself
over the area through the second half of next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 91 66 88 65 / 10 5 10 10
San Angelo 92 64 89 63 / 10 5 10 10
Junction 91 64 90 61 / 5 5 10 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Johnson
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1230 PM CDT THU SEP 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM CDT THU SEP 24 2015
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING UPPER LEVEL
LOW/TROUGH SPINNING OVER EASTERN NEBRASKA WITH SEVERAL PIECES OF
ENERGY ROTATING AROUND THE UPPER LEVEL TROUGH INTO THE NORTHERN
PLAINS AND UPPER MIDWEST. LATEST KARX RADAR SHOWS LIGHT RAIN SHOWERS
OVER SOUTHEAST MINNESOTA/WESTERN WISCONSIN IN ASSOCIATION WITH WEAK
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN.
THE 24.00Z GFS/NAM AND 24.05Z RAP SUGGEST WEAK IMPULSES ROTATING
AROUND UPPER LEVEL TROUGH TO LIFT NORTHWARD INTO PARTS OF NORTHERN
IOWA/SOUTHERN MINNESOTA TODAY. 24.00Z MODELS SUGGEST WEAK
FORCING/MOISTURE CONVERGENCE TO LIFT NORTHWARD ALONG WITH THE
IMPULSE OVER EASTERN MINNESOTA/WESTERN WISCONSIN TODAY. IN
ADDITION...SURFACE RIDGE BUILDS INTO THE EASTERN WISCONSIN AFTER 18Z
TODAY. EXPECT THE LIGHT RAIN SHOWERS TO LINGER ACROSS THE FAR
NORTHERN/NORTHWEST PARTS OF THE FORECAST AREA EARLY THIS MORNING
AND TRACK NORTHWARD OUT OF THE FORECAST AREA BY 18Z TODAY.
TONIGHT...WITH SURFACE RIDGE BUILDING INTO THE FORECAST AREA AND
LIGHT WINDS NEAR SURFACE BOUNDARY LAYER AND ALOFT. PATCHY FOG IS A
POSSIBILITY IN RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN. BIG
QUESTION WILL BE IF CLOUDS CLEAR OUT OF THE FORECAST AREA IN TIME TO
ALLOW FOR INVERSION TO DEVELOP AND FOG FORMATION. THE 24.00Z GFS/NAM
SHOW SLIGHT DIFFERENCES IN TIMING OF THE CLOUDS TO CLEAR FROM NORTH
TO SOUTH ACROSS THE FORECAST AREA...PER RELATIVE HUMIDITY FIELDS.
FOR NOW...HAVE LEFT MENTION OF PATCHY FOG IN RIVER VALLEYS AND THE
PREFERRED AREAS OF CENTRAL WISCONSIN.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 AM CDT THU SEP 24 2015
MAIN FORECAST CONCERN IS FOG FORMATION FRIDAY NIGHT INTO SATURDAY
MORNING IN RIVER VALLEYS AND CENTRAL WISCONSIN. SURFACE RIDGE AND
RIDGING ALOFT OVER THE GREAT LAKES REGION WILL DOMINATE THE AREA
FRIDAY INTO SATURDAY NIGHT. WITH CLEAR SKIES...LIGHT WINDS NEAR
THE SURFACE BOUNDARY LAYER...AND STRONG INVERSION DEVELOPS AFTER
06Z SATURDAY...FOG WILL BE POSSIBLE IN RIVER VALLEYS AND IN PARTS
OF CENTRAL WISCONSIN FRIDAY NIGHT INTO EARLY SATURDAY MORNING.
INTRODUCED PATCHY FOG FROM 08-14Z SATURDAY.
WITH SURFACE/UPPER LEVEL RIDGE IN CONTROL OF THE AREA...DRY WEATHER
CAN BE EXPECTED FRIDAY INTO SATURDAY. TEMPERATURES FRIDAY INTO
SATURDAY WILL REMAIN ABOVE NORMAL...WITH THE 24.00Z GFS/NAM/ECMWF
INDICATING 925MB TEMPERATURES RANGING FROM PLUS 17 TO PLUS 19
DEGREES CELSIUS ACROSS THE FORECAST AREA.
SUNDAY INTO WEDNESDAY...FORECAST CONCERNS ARE TEMPERATURES THROUGH
THE PERIOD AND PRECIPITATION CHANCES TUESDAY INTO WEDNESDAY. THE
24.00Z GFS/GEM/ECMWF SHOW SIGNIFICANT DIFFERENCES ON TIMING/STRENGTH
OF UPPER LEVEL TROUGH DIGGING OVER THE GREAT LAKES REGION AND
EMBEDDED SHORTWAVE ENERGY IN THE UPPER LEVEL TROUGH MONDAY INTO
WEDNESDAY. THIS WILL HAVE IMPACTS ON TIMING OF SMALL PRECIPITATION
CHANCES TUESDAY INTO WEDNESDAY. TEMPERATURES WILL REMAIN ABOVE
NORMAL SUNDAY INTO MONDAY...AS WARM AIR ADVECTS INTO FORECAST AREA
OUT AHEAD OF SHORTWAVE ENERGY/SURFACE FRONT PUSHING INTO THE
NORTHERN MINNESOTA AND OVER LAKE SUPERIOR. COOLER AIR IS EXPECTED
TO FILTER IN BEHIND SURFACE FRONT/SHORTWAVE TUESDAY INTO
WEDNESDAY...AS THE 24.00Z GFS/ECMWF SUGGEST PLUS 3 TO PLUS 10
DEGREES CELSIUS BY 12Z WEDNESDAY ACROSS FORECAST AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1230 PM CDT THU SEP 24 2015
CUT OFF LOW OVER EASTERN NEBRASKA AND ASSOCIATED LARGE AREA OF VFR
CEILINGS ABOUT ONLY ISSUE TO CONCERN WITH. AIRMASS REMAINS FAIRLY
DRY IN LOWER LEVELS SO LOTS OF MID LEVEL CLOUDS AROUND FORECAST
AREA.
NOTICED UPPER LOW IS STARTING TO FILL A LITTLE AND MODEL GUIDANCE
STILL SUGGESTS THAT TREND WILL CONTINUE NEXT 24 HOURS. ASSOCIATED
LIFT WILL CONTINUE TO DIMINISH AS WELL SO ANY PRECIPITATION THREAT
SHOULD REMAIN MAINLY WEST AND LOWER IN TIME. STILL HAVE A LOT OF
CLOUDS AROUND THOUGH SO HAVE DELAYED CLEARING IDEA NEARLY 10-12
HOURS WHICH HAS IMPLICATIONS ON ANY FOG POSSIBILITIES FRIDAY
MORNING. WHILE WE COULD SEE SOME THINNING IN CLOUDS MAINLY ON
WISCONSIN SIDE...NOT ENOUGH CONFIDENCE TO KEEP FOG AT KLSE WITH
EXPECTED CLOUDS AROUND.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...SHEA
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
433 PM MDT THU SEP 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 200 PM MDT THU SEP 24 2015
DRY AND WARM WEATHER WILL HOLD OVER THE CWA THROUGH SATURDAY
COMPLEMENTS OF AN UPPER RIDGE THAT WILL BE OVER THE CWA THROUGH
MOST OF THE PERIOD. THE RIDGE WILL WEAKEN SOME LATER SATURDAY AS
SHORTWAVE ENERGY MOVES ACROSS SOUTHERN CANADA BUT THATS ABOUT THE
ONLY WEATHER FEATURE OF NOTE OVERALL. SOME MAINLY VALLEY FOG WILL
BE POSSIBLE AGAIN LATER TONIGHT INTO FRIDAY MORNING OVER THE NEB
PANHANDLE AS WEAK EASTERLY FLOW MAY ADVECT IN SUFFICIENT MOISTURE
UNDER CLEAR SKIES. TEMPERATURES WILL REMAIN ABOVE SEASONAL NORMS
BOTH DAYS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 200 PM MDT THU SEP 24 2015
12Z MEDIUM RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THE
RIDGE AXIS FROM THE UPPER MIDWEST TO DESERT SOUTHWEST SLOWLY
DRIFTING SOUTH AS SHORTWAVE ENERGY TRACKS EAST FROM THE PACIFIC
NORTHWEST ACROSS THE NORTHERN TIER OF THE CONUS THROUGH MONDAY.
THE GFS SHOWS A VORT LOBE EXTENDING FROM IA WESTWARD ACROSS
SOUTHERN WY MONDAY NIGHT THROUGH TUESDAY...PULLING A PACIFIC
FRONT ACROSS THE CWA. THE ECMWF MAINTAINS A WEAK RIDGE ALOFT WITH
A WEAKER SHORTWAVE FURTHER NORTH. BOTH MODELS PRODUCE WIDELY
SCATTERED CONVECTION...MAINLY IN THE VICINITY OF THE MOUNTAINS
AND NORTHEAST CWA. IT WILL BE BREEZY EACH AFTERNOON WEST OF THE
LARAMIE RANGE...WITH LIGHTER WINDS ELSEWHERE. IT WILL BE QUITE
WARM SUNDAY AND MONDAY WITH HIGHS IN THE 70S AND 80S...COOL 5 TO
10 DEGREES TUESDAY...FOLLOWED BY SLIGHT WARMING WEDNESDAY AND
THURSDAY. LOWS WILL RANGE FROM THE 40S TO LOW 50S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 431 PM MDT THU SEP 24 2015
IFR/LIFR CONDITIONS EXPECTED TO RETURN TONIGHT FOR SEVERAL
NEBRASKA PANHANDLE AIRPORTS. HRRR GUIDANCE USED HEAVILY IN THE 00Z
TAFS AS IT DID EXTREMELY WELL LAST NIGHT. LOWERING CONDITIONS
EXPECTED TO BEGIN AT KAIA AROUND 04Z...THEN KCDR AND KSNY RIGHT
AROUND 06Z. EXPECTED TO LAST THROUGH MID MORNING. VFR CONDITIONS
EXPECTED ACROSS SOUTHEAST WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 200 PM MDT THU SEP 24 2015
DRY AND WARM CONDITIONS ARE EXPECTED TO CONTINUE INTO EARLY NEXT
WEEK. SOME ELEVATED CONCERNS IN THE AFTERNOONS OVER WESTERN SECTIONS
WHERE WINDS SHOULD COME UP A BIT BUT NOT LOOKING TOO STRONG AT THIS
TIME.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RE
LONG TERM...MAJ
AVIATION...GCC
FIRE WEATHER...RE