[USA] Onweersverwachting 24 Feb

Wederom heeft het SPC zojuist onverwachts geupgrade naar een "Slight Risk" voor het zuiden en oosten van Florida in verband met een versnelde 'voor'. Deze ochtend zijn er al enkele onweersbuien Florida binnengedreven, maar de echte actie word pas aan het einde van de middag en het begin van de avond verwacht, wanneer onweerscellen met zware windstoten en grote hagel Florida zullen binnendrijven. Verwacht word dat enkele van deze onweerscellen uit zullen groeien tot supercells, waardoor de tornadokans significant hoger ligt dan afgelopen dagen.

SPC verwachting



...There is a slgt risk of svr tstms over srn and e cntrl fl...

...Synopsis...
In response to closed system amplifying sewd into the oh vly...
expect positive-tilt trough now over the nw gulf of mexico to
accelerate e across the n cntrl and ne gulf later today...before
continuing newd off nc cst early thu. At the sfc...weak wave now
evolving along stalled/disjointed front w of key west should move
newd into s fl later today. The wave likely will be joined by
additional sfc development farther ne...along frontal segment n/e of
lk okeechobee. The later wave should become dominant by early
afternoon...and should accelerate newd off the cst late in the day.

...Srn/e cntrl fl...
Tstms have formed overnight in zone of strengthening waa/moisture
flux along and n of stalled front s of the fl keys. This activity
should increase and spread newd as wrn gulf upr trough continues
ewd. Additional storms likely will form later this morning through
early aftn invof aforementioned sfc wave over sern/e cntrl fl...and
perhaps swd along cstl convergence zone to near mia....as swly
low-lvl flow increases to a0a 30 kts.

Proximity of 120+ kt zonal subtropical jet...associated 60+ kt wly
mid lvl flow...and weak low-lvl linear forcing will favor discrete
or semi-discrete sustained storms/supercells. Combination of sfc
dewpoints in the mid to upr 60s f...pw aoa 1.25 in...residual eml
/per 12z mia sounding/...and modest sfc heating should yield sbcape
of 500-1000 j/kg by early afternoon. The storms may therefore pose
a threat for svr hail...locally dmgg wind...and perhaps a tornado or
two. The threat should end by early evening as the low-lvl flow
veers and the strongest low-lvl convergence shifts offshore.

_spc.noaa.gov | Gewijzigd: 24 februari 2010, 15:24 uur, door Narmolanya

Ik lees net dat er kans is op hagelstenen van 3 a 4 inch. Dat is ongeveer 7,5 tot 10 cm! Best pittig dus!

Alvast een leuk begin, de echte cellen zullen pas later volgen. Bij mij staat de radar open in ieder geval! | Gewijzigd: 24 februari 2010, 18:52 uur, door Narmolanya

Citaat van Joey, woensdag 24 februari 2010, 19:01 uur Waar haal je deze informatie vandaan?
bvd!

Van een programma genaamd grlevel3 en de data van alisonhouse ( kost wel geld)

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
NORTHERN MIAMI-DADE COUNTY IN SOUTHEAST FLORIDA...
THIS INCLUDES THE CITIES OF...SOUTH MIAMI...MIAMI...KENDALL...
HOMESTEAD...HIALEAH...CORAL GABLES...

* UNTIL 145 PM EST

* AT 122 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
CLUSTER OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THE CENTER OF THE
STORMS WAS LOCATED 5 MILES NORTHWEST OF REDLAND...AND MOVING
NORTHEAST AT 35 MPH.

* THE STORM WILL AFFECT...
THE REDLAND...
GOULDS...
INTERSECTION KROME AND KENDALL DRIVE...
KENDALE LAKES...
AND SURROUNDING COMMUNITIES.

Severe Thunderstorm Watch 18



URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 18
NWS STORM PREDICTION CENTER NORMAN OK
135 PM EST WED FEB 24 2010

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

SOUTH FLORIDA
COASTAL WATERS

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 135 PM UNTIL
800 PM EST.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES WEST
NORTHWEST OF VERO BEACH FLORIDA TO 70 MILES SOUTHWEST OF MIAMI
FLORIDA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...THUNDERSTORMS WILL CONTINUE INCREASING IN COVERAGE AND
INTENSITY ACROSS SRN FL THIS AFTERNOON. 17Z SPECIAL SOUNDING FROM
MFL INDICATE MODEST INSTABILITY BUT STEEP LAPSE RATES AND STRONG
LOW/DEEP LAYER SHEAR. THIS SUGGESTS ADDITIONAL POTENTIAL FOR LARGE
HAIL AND DAMAGING WINDS AS ACTIVITY EVOLVES AS SUPERCELLS AND
CLUSTERS OF STRONGER STORMS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 350. MEAN STORM
MOTION VECTOR 26020.

Citaat van zorba, woensdag 24 februari 2010, 19:00 uur Is er zo'n radar online te volgen?

Er bestaat een goede online radar van NOAA. Zie onderstaande link.
http://radar.srh.noaa.gov/

Even een radarbeeldje erbij:

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN MARTIN COUNTY IN FLORIDA

* UNTIL 345 PM EST.

* AT 307 PM EST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 13
MILES WEST OF JOHNATHAN DICKINSON STATE PARK...OR 8 MILES EAST OF
INDIANTOWN...AND MOVING EAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
JONATHAN DICKINSON STATE PARK...AND HOBE SOUND BY 325 PM EST...

Citaat van Narmolanya, woensdag 24 februari 2010, 22:46 uur Pff, wat heb jij een verschrikkelijk rommelig radarbeeld bjk22
Haha ik ben het ondertussen gewend Gebruik het programma nu een jaat.