Re: Tornado Alley Forecasts, Nowcasting and Reports
aggiornamenti in Day3 Outlook.
SPC AC 260825
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0225 AM CST MON FEB 26 2007
VALID 281200Z - 011200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF ERN OK...AR
AND SERN MO...
...SYNOPSIS...
BROAD UPPER TROUGH OVER THE WRN CONUS WILL SHIFT EWD INTO THE
CENTRAL PORTIONS OF THE COUNTRY BY THURSDAY MORNING...WITH A CLOSED
LOW FORECAST TO DEVELOP OVER THE NRN PLAINS. LARGE SWATH OF 70 TO 90
KT MID LEVEL WINDS...ON THE SRN PERIPHERY OF THIS TROUGH...IS
EXPECTED TO SPREAD EWD FROM THE SWRN STATES INTO TX/OK. ALTHOUGH THE
LOCATION OF THE UPPER TROUGH IS SIMILAR ON THE VARIOUS MODELS ...THE
LOCATION OF THE SURFACE LOW AND SPEED OF FRONT VARIES DUE TO
STRENGTH OF NRN PLAINS UPPER LOW. PREFER EURO AND SREF SURFACE
SOLUTIONS...WHICH ARE A COMPROMISE BETWEEN NAM AND GFS...SUGGESTING
AT 01/12Z...SURFACE LOW WILL BE LOCATED IN NERN MO/WRN IL WITH COLD
FRONT TRAILING SWWD INTO ERN OK/CENTRAL TX.
...ERN OK/AR/SRN MO...
ALTHOUGH BOUNDARY LAYER MOISTURE WILL BE INCREASING THROUGH THE DAY
ACROSS ERN TX/OK AR AND LA...EXPECT MOST OF THE DAY TO BE CONVECTIVE
FREE AS 30-40 KT SWLY WINDS AT 850 MB ADVECT A WARM AND DRY AIRMASS
ABOVE THE MOISTENING BOUNDARY LAYER. HOWEVER...FORCING FOR
CONVECTION WILL INCREASE WEDNESDAY NIGHT AS 500MB HEIGHTS FALL
AROUND 60M AND LOW LEVEL JET STRENGTHENS TO 60 KT. FORECAST
SOUNDINGS SUGGEST THE AIR MASS WOULD STAY CAPPED THROUGH MOST OF THE
NIGHT...THOUGH STEEP LAPSE RATES MUCAPES AROUND 1000 J/KG AND BULK
SHEAR AT 40 KT WOULD SUPPORT A THREAT FOR SEVERE HAIL. SURFACE BASED
STORMS MAY ALSO DEVELOP ALONG THE FRONT LATE IN THE NIGHT AS SURFACE
PARCELS ARE FORCED THROUGH THE CAP. IF THIS HAPPENS...A WIND THREAT
IS POSSIBLE...THOUGH THE MORE SIGNIFICANT SEVERE WEATHER ACTIVITY S
LIKELY TO WAIT FOR DIURNAL HEATING AND GREATER INSTABILITY DURING
THE DAY THURSDAY.
ELSEWHERE...STRONG CAP IS LIKELY TO LIMIT CONVECTIVE DEVELOPMENT SWD
ALONG THE FRONT INTO CENTRAL/ERN TX WEDNESDAY NIGHT...WHILE ELEVATED
STORMS WITH A HAIL POTENTIAL ARE POSSIBLE IN SRN IL.
..IMY.. 02/26/2007
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1100Z
CURRENT UTC TIME: 0906Z (10:06AM), RELOAD THIS PAGE TO UPDATE THE TIME
Stornoway, Isle of Lewis, Outer Hebrides, Scotland - 58° 12' 33.96" N - 06° 23' 05.52" O - 15m s.l.m.
"Always Looking At The Sky"
Re: Tornado Alley Forecasts, Nowcasting and Reports
aggiorniamo in Day2 Outlook...non male, le condizioni sono interessanti
SPC AC 271741
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1141 AM CST TUE FEB 27 2007
VALID 281200Z - 011200Z
...THERE IS A SLGT RISK OF SVR TSTMS ERN OK TO WRN/NRN MS...AND NRN
LA TO NRN MO AND SWRN IL...
...SYNOPSIS...
SIGNIFICANT UPPER AIR PATTERN SHIFT WILL TAKE PLACE THROUGH DAY-2
AND BEYOND...WITH BROAD AREA OF HEIGHT FALLS ALOFT CHARACTERIZING
ROCKIES AND GREAT PLAINS STATES THROUGH MUCH OF PERIOD. SHORTWAVE
DETAILS ARE COMPLEX WITH THIS PATTERN...BUT HANDLED REASONABLY
CONSISTENTLY BY BOTH OPERATIONAL SHORT-RANGE MODELS AND LATEST SREF
PACKAGE.
MID-UPPER LEVEL SHORTWAVE TROUGH NOW OVER ID IS FCST TO MOVE EWD
ACROSS NRN HIGH PLAINS AND EVOLVE INTO CLOSED LOW OVER WRN DAKOTAS
BY 1/00Z. MEANWHILE...PRONOUNCED CYCLONIC VORTEX NOW NEAR NWRN TIP
OF ORE WILL WEAKEN AND EJECT NEWD OVER PACIFIC NW...AS UPSTREAM
TROUGH DIGS SEWD FROM SERN GULF OF AK. THESE PROCESSES WILL ALLOW
SHORTWAVE PERTURBATION -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY
NEAR 41N132W -- TO AMPLIFY AS IT MOVES SEWD TOWARD SRN NV/SRN CA BY
28/12Z. DURING DAY-2 THIS TROUGH SHOULD MOVE RAPIDLY EWD ACROSS SRN
ROCKIES AND SRN HIGH PLAINS...THEN NEWD OVER ERN KS...EMBEDDED IN
CYCLONIC FLOW ASSOCIATED WITH NRN PLAINS LOW.
ASSOCIATED SFC RESPONSE WILL BE PRONOUNCED AS LEE TROUGHING NOW
ANALYZED IN SRN/CENTRAL HIGH PLAINS FCST TO EVOLVE INTO RAPIDLY
DEEPENING LOW ACROSS SWRN KS...OK PANHANDLE OR NRN TX PANHANDLE BY
1/00Z. DURING FOLLOWING 12 H...THIS LOW SHOULD DEEPEN AND EJECT
NEWD ALONG WARM FRONT INTO W-CENTRAL/NWRN MO. TRAILING COLD FRONT
WILL SWEEP EWD/SEWD ACROSS MOST OF KS...OK AND NW TX. FOREGOING
DRYLINE WILL STRENGTHEN THROUGH 1/00Z OVER CENTRAL OK AND CENTRAL
TX. EXPECT NRN EDGE OF RETURNING GULF AIR MASS TO COMPRISE
SECONDARY WARM FRONT/MARINE FRONT...WHICH WILL LIFT NEWD ACROSS
LA...AR...WRN/SRN MS AND PERHAPS SERN MO/WRN TN REGION BY END OF
PERIOD.
...SRN/CENTRAL LOW PLAINS...BEFORE DARK...
CONDITIONAL SVR THREAT WILL EXTEND WWD INTO PORTIONS CENTRAL OK AND
N-CENTRAL/NERN TX...AND NWD ACROSS SERN KS/MO...N OF STRONGEST
CAPPING. LATEST GUIDANCE INDICATES DRYLINE SHOULD BE LOCATED ALONG
OR JUST W OF I-35 OVER TX AND OK BY 1/00Z...WITH NARROW PLUME OF AT
LEAST MRGLLY FAVORABLE LOW LEVEL MOISTURE INTO WRN MO BETWEEN 28/21Z
AND 1/06Z. CAPPING WILL LIMIT AMOUNT/COVERAGE OF CONVECTION BEFORE
DARK...BUT A FEW TSTMS MAY INITIATE ALONG LATE AFTERNOON DRYLINE AND
BECOME SVR...WITH LARGE HAIL BEING MAIN THREAT AND SVR GUSTS PSBL.
VERTICAL MIXING ALONG NWRN EDGE OF RETURN FLOW AIR MASS MAY KEEP
DIURNAL LCL RELATIVELY HIGH...BUT MODIFIED MODEL SOUNDINGS SUGGEST
STEEPENING LOW-MIDLEVEL LAPSE RATES...NEARLY UNCAPPED BOUNDARY LAYER
FOR TEMPS LOW-MID 70S F...AND MLCAPES 500-1000 J/KG. VERTICAL SHEAR
PROFILES WILL BE FAVORABLE FOR SUPERCELLS...WITH 0-6 KM SHEAR UP TO
NEAR 75 KT...AND 0-1 KM SRH POTENTIALLY 250-300 J/KG.
...ERN TX...OK TO LOWER MS VALLEY/DELTA...NIGHTTIME...
STRONG VERTICAL SHEAR PROFILES ARE FCST TO OVERSPREAD LARGE PART OF
S-CENTRAL CONUS AND LOWER MS VALLEY DURING THIS PERIOD. AS BOUNDARY
LAYER THETAE INCREASES ACROSS THIS REGION THROUGHOUT OVERNIGHT
HOURS...SUPERCELLS WITH LARGE HAIL...DAMAGING GUSTS AND TORNADOES
ARE POSSIBLE...WHEREVER CAP MAY BREAK. LATE AFTERNOON/EVENING TSTMS
-- INITIATED INVOF DRYLINE -- MAY MOVE EWD INTO INCREASINGLY MOIST
AIR MASS WITH LOWERING LCL...MAINTAINING POTENTIAL FOR SVR HAIL/WIND
AND INCREASING TORNADO THREAT. MAIN QUESTION ATTM IS
COVERAGE....GIVEN STRENGTH OF CAPPING FCST AT BASE OF ELEVATED
MIXED-LAYER. LOW LEVEL MOISTURE WILL BECOME FAVORABLE THROUGH
OVERNIGHT HOURS...ALONG AND S OF RETURNING MARINE FRONT...WITH SFC
DEW POINTS GENERALLY IN 60S F. MOIST ADVECTION...AND BOUNDARY LAYER
WAA...WILL OFFSET DIABATIC COOLING AND KEEP EFFECTIVE LIFTED PARCELS
ROOTED AT OR NEAR SFC THROUGH END OF PERIOD.
MAIN CONCERN FOR INITIATION WILL BE LACK OF DISTINCT FOCI IN WARM
SECTOR AND S OF MARINE FRONT. HOWEVER...CAPPING RELATED TO ELEVATED
MIXED LAYER SHOULD WEAKEN WITH EWD EXTENT NEAR MARINE FRONT. THIS
MAY RESULT IN SECONDARY LOBE OF SVR POTENTIAL AFTER DARK...SOMEWHERE
INVOF WRN MS/SERN AR/NERN LA. SPATIALLY...WRN PORTION OF THIS
THREAT MAY EXTEND INTO ERN PORTION OF LATER-ARRIVING AND MORE
STRONGLY FORCED CONVECTIVE POTENTIAL ASSOCIATED WITH PACIFIC
FRONT/DRYLINE. THEREFORE THIS OUTLOOK WILL MAINTAIN ONE CONTIGUOUS
THREAT AREA.
..EDWARDS.. 02/27/2007
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0800Z
CURRENT UTC TIME: 1834Z (7:34PM), RELOAD THIS PAGE TO UPDATE THE TIME
Stornoway, Isle of Lewis, Outer Hebrides, Scotland - 58° 12' 33.96" N - 06° 23' 05.52" O - 15m s.l.m.
"Always Looking At The Sky"
Re: Tornado Alley Forecasts, Nowcasting and Reports
Compare il primo (mi pare, se non mi sbaglio) "moderate risk" della stagione.
"
THUNDERSTORMS ARE LIKELY TO DEVELOP DURING THE AFTERNOON AS STRONG
DIFFLUENT FLOW ALOFT SPREADS IN FROM THE WEST. AS THE LIFT INCREASES
ACROSS THE WEAKLY CAPPED ENVIRONMENT...CELLULAR STORMS ARE EXPECTED
TO DEVELOP...AND 60-70 KT DEEP LAYER SHEAR WOULD SUPPORT NUMEROUS
SUPERCELLS. THE MOIST BOUNDARY LAYER AND 20-30 KT 1KM SHEAR WOULD BE
FAVORABLE FOR WIND DAMAGE AND TORNADOES...SOME STRONG. "
Re: Tornado Alley Forecasts, Nowcasting and Reports
Originariamente Scritto da Cumulo
no sei rimasto indietro, è il terzo
Re: Tornado Alley Forecasts, Nowcasting and Reports
il mio target x oggi potrebbe essere guthrie, appena a nord di oklahoma city, sempre nella speranza che la dry line si attivi prima del tramonto. a dopo x aggiustamenti
Re: Tornado Alley Forecasts, Nowcasting and Reports
il mio target x oggi potrebbe essere guthrie, appena a nord di oklahoma city, sempre nella speranza che la dry line si attivi prima del tramonto. a dopo x aggiustamenti
questa volta ti sto incollato; 200 mt di distanza
And if the cloud bursts Thunder in your ear, You shout and no one seems to hear
----------------------------
always looking at the sky
Re: Tornado Alley Forecasts, Nowcasting and Reports
il mio target x oggi potrebbe essere guthrie, appena a nord di oklahoma city, sempre nella speranza che la dry line si attivi prima del tramonto. a dopo x aggiustamenti
come mai cos'ì a Ovest ?
non sarebbe meglio piazzarsi al confine fra l'Arkansas e il Mississippi al lato sud est del mdr risk ?
Ultima modifica di meteogio; 28/02/2007 alle 14:42
Re: Tornado Alley Forecasts, Nowcasting and Reports
Mi Metto In Alabama...a Birmingham
Storm chaser for Thunderstorm Team
UG 69
Re: Tornado Alley Forecasts, Nowcasting and Reports
Mi Metto In Alabama...a Birmingham
eh si in Polinesia
stesso discorso, io e Ben parlavamo del target x oggi
Re: Tornado Alley Forecasts, Nowcasting and Reports
io per stasera non riuscirò a seguire questa bottarella di temporali...ma domani dalla mattina sarò in prima linea con il chasing.
intanto la situazione si prospetta veramente interessate
Stornoway, Isle of Lewis, Outer Hebrides, Scotland - 58° 12' 33.96" N - 06° 23' 05.52" O - 15m s.l.m.
"Always Looking At The Sky"
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