ATL : INVEST 92L - DISCUSSION

[tailgater]

latest ASCAT scan (4:01UTC/12:01ET) caught most of Invest 92L, center appears elongated from NE to SW but evident.

Certainly nothing near T.S. force on that chart. Barely a TD if the LLC is aligned with the mid level circ. we see in the IR loops. Seems to be gaining Lat or maybe LLC is tucking under the Circ. we see in the IR loops.

[Brent]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT MON JUN 14 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A LARGE LOW PRESSURE SYSTEM LOCATED ABOUT 1025 MILES WEST-SOUTHWEST
OF THE CAPE VERDE ISLANDS HAS CHANGED LITTLE DURING THE PAST SEVERAL
HOURS. HOWEVER...ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN
CONDUCIVE FOR ADDITIONAL DEVELOPMENT OF THIS DISTURBANCE AS IT
MOVES WEST-NORTHWESTWARD TO NORTHWESTWARD AT ABOUT 15 MPH. THERE
REMAINS A HIGH CHANCE...60 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART/BLAKE

[caribepr]

60 percent...ok, we're watching

[Cyclenall]

I checked the NRL before calling it a night two hours ago and now look... An Invest this far east and south for June that is this organized (I could see how vigorous the rotation was before even viewing a loop) is shocking. There are only a few examples comparable to this but even those were just TD's that were a bit later in June.

[USTropics]

latest ASCAT scan (4:01UTC/12:01ET) caught most of Invest 92L, center appears elongated from NE to SW but evident.

Certainly nothing near T.S. force on that chart. Barely a TD if the LLC is aligned with the mid level circ. we see in the IR loops. Seems to be gaining Lat or maybe LLC is tucking under the Circ. we see in the IR loops.

Current NRL position puts 92L at 8.4N. Position at 1PM ET was around 7N if I recall correctly. The elongation of the center I would assume has to do with the 92L's location to the equator, and the lack of a strong Coriolis effect. It will be interesting to see how 92L performs through diurnal maximum and if the cooling cloud tops located to the north can sustain and wrap around the COC.

[blp]

Though extremely rare not the first time a June storm has formed in this area. Jeff Masters posted the below image on his blog about T.S. Ana in 1979. One thing to note is that Ana started on June 19th so wannabe Alex might be the earliest recorded storm if forms in the next day or two. It is possible though a storm might have existed pre satellite era.

[Fego]

Uploaded with ImageShack.us

Amazing Atlantic indeed. 92L behaved well but not for an upgrade.

[StarmanHDB]

Looks like definite convection firing near/at the center....

http://raleighwx.easternuswx.com/models ... 4kmIR.html

[Aquawind]

Sure does..impressive alright.

[USTropics]

14/0545 UTC 9.1N 38.6W T1.0/1.0 92L

92L appears to be consolidating a bit more to the north now (of the current 8.4N location that NRL had as of 30 minutes ago). Current satellite images show convection forming directly to the north and west of this position, so seems pretty accurate to me.

[KWT]

Its getting a bit of a curved look to that convection now, seems like some limited banding is just starting to occur as the convection wraps around the circulation.

Anyway shear is still pretty hefty at 50W, so its got a window to develop and if it doesn't do it by then, 92L is going to struggle to even survive.

[Gustywind]

[KWT]

First Vis images show the convection wrapping very nicely at the moment towards the center. Probably going to need to get higher T-numbers before it gets upgraded however...

[Gustywind]

000
FXCA62 TJSJ 140940
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
540 AM AST MON JUN 14 2010

.SYNOPSIS...AT UPPER LEVELS...AN EAST-WEST TROUGH JUST SOUTH OF
PUERTO RICO AND THE U.S. VIRGIN ISLANDS WILL PASS OVER WEDNESDAY
NIGHT AND THEN RETREAT TO THE NORTHWEST AS A RIDGE NOSES IN FROM
THE EAST. FLOW WILL REMAIN SOUTHWEST AFTER WEDNESDAY.

AT MID LEVELS...HIGH PRESSURE WILL STRETCH FROM THE SOUTHEAST
UNITED STATES TO THE TROPICAL ATLANTIC THROUGH SATURDAY. HIGH
PRESSURE WILL BUILD BRIEFLY NORTHEAST OF PUERTO RICO SUNDAY
AND MONDAY BUT STRONGER HIGH PRESSURE WILL BUILD WEST OF AFRICA
AROUND 22 NORTH MID-WEEK NEXT WEEK.

AT LOWER LEVELS...HIGH PRESSURE NORTH OF THE LOCAL AREA REMAINS
BETWEEN 20 AND 35 NORTH FOR THE NEXT 10 DAYS. SEVERAL BANDS OF
MOISTURE WILL PRECEDE A SIGNIFICANT TROPICAL WAVE DUE TO ARRIVE
ON SATURDAY. THIS TROPICAL WAVE WILL APPROACH 40 WEST THIS
MORNING. A SECOND WAVE IS LEAVING AFRICA NOW AND WILL MOVE THROUGH
THE AREA LATER NEXT WEEK.

&&

.DISCUSSION...THE WEATHER SHOWS A CONTINUING PATTERN OF MODERATE
EAST SOUTHEAST TRADE WINDS AND WIDE BANDS OF BETTER MOISTURE
CONTRIBUTING TO SCATTERED SHOWERS ON THE EASTERN SIDE OF PUERTO
RICO AND AROUND THE U.S. VIRGIN ISLANDS IN THE EARLY MORNINGS AND
AFTERNOON SHOWERS AND THUNDERSTORMS IN THE WEST DURING THE
AFTERNOONS. LATEST MODELS SHOW MOISTURE...ESPECIALLY THE
PRECIPITABLE WATER...INCREASING MORE OR LESS STEADILY BETWEEN
TODAY AND TUESDAY OF NEXT WEEK FROM ABOUT 1.4 INCHES TO OVER 2.3 INCHES.
DURING THIS TIME A WEAK TROPICAL WAVE WILL PASS MID WEEK...A
SECOND MORE SIGNIFICANT WAVE...WHICH IS CURRENTLY BEING MONITORED
FOR DEVELOPMENT INTO A TROPICAL CYCLONE...IS EXPECTED TO PASS ON
SATURDAY. THIS WAVE WILL BRING WITH IT CONSIDERABLY MORE SHOWERS
AND THUNDERSTORMS...BUT...MORE IMPORTANTLY...NOW APPEARS TO
REPRESENT AN INCREASE IN MOISTURE THAT WILL PERSIST THROUGH AT
LEAST MONDAY NIGHT. A THIRD WAVE...CURRENTLY LEAVING AFRICA WILL
BE POISED TO ENTER THE CARIBBEAN MID WEEK NEXT WEEK. MODELS DO NOT
DEVELOP THE WAVE APPROACHING 40 WEST LONGITUDE INTO A TROPICAL
CYCLONE AT THIS TIME...BUT THERE IS CONSIDERABLE ROTATION VISIBLE
AROUND ITS CENTER AND WHAT WOULD APPEAR TO BE SPIRAL BANDS. IN
ADDITION TO THIS VISIBLE STRUCTURE THERE IS LITTLE SHEAR AND
FAVORABLE OCEAN WARMTH TO INDUCE GROWTH. WHETHER IT CAN SURVIVE A
TRANSITION OF UPPER LEVEL WINDS FROM NORTHEAST TO SOUTHWEST AS IT
APPROACHES IS OF NO LITTLE CONSEQUENCE AND AT THIS TIME WOULD TEND
TO GO WITH THE MODELS AND MERELY INDICATE A WET WEEKEND FOR PUERTO
RICO AND PERHAPS SOME RAINS FOR THE U.S. VIRGIN ISLANDS AS WELL AS
AN OPEN WAVE MOVES THROUGH THE AREA. SOME OF THE THUNDERSTORMS
THAT ACCOMPANY THIS WAVE COULD HAVE PARTICULARLY GUSTY WINDS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 80 90 79 / 10 30 30 30
STT 89 80 89 80 / 20 20 20 30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&

$$

11/12

[tolakram]

If that's the center it's looking pretty healthy.

[cycloneye]

Right now I am not concerned at all if shear rips 92L apart. My concern is that our potentially first named storm may form in the middle of June and where the location is. A worrisom sign for the rest of the 2010 season.

[cycloneye]

Looking very good.

[wzrgirl1]

Wow this could be an unprecedented season with three fairly decent waves emerging off of Africa already. I can only imagine the ocean temps...lol my pool is already reading 91 degrees. A weak comparison I know, but just shows the possible heat content in the ocean. Usually my pool doesn't reach this temp until August. Craziness.

[Nimbus]

According to the Quickscat it looks like there were winds wraping from the west that closed off the circulation earlier on the south side of the system. It doesn't sound like the shear forecast is is going to be as much help as we thought either. Usually a TUTT or something sets up west of the system sometime during the longer term forecast and this storm is still a long way from threatening the mainland. I guess the islands would not be much concerned with just a tropical storm since its only June and rapid development would go against climatology.

[RL3AO]

According to the Quickscat it looks like there were winds wraping from the west that closed off the circulation earlier on the south side of the system. It doesn't sound like the shear forecast is is going to be as much help as we thought either. Usually a TUTT or something sets up west of the system sometime during the longer term forecast and this storm is still a long way from threatening the mainland. I guess the islands would not be much concerned with just a tropical storm since its only June and rapid development would go against climatology.

Quikscat died last season (RIP), that image is from the much less useful ASCAT.