The storm that is most likely to become Erika is consolidating now east of the Lesser Antilles: http://www.ssd.noaa.gov/goes/east/catl/l....

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM
http://www.ssd.noaa.gov/goes/flt/t2/loop....


TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SUN AUG 30 2009

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

1. CLOUDINESS AND SHOWERS ASSOCIATED WITH A BROAD AREA OF LOW PRESSURE
LOCATED ABOUT 950 MILES EAST OF THE WINDWARD ISLANDS CONTINUE TO
BECOME BETTER ORGANIZED. THIS SYSTEM COULD BECOME A TROPICAL
DEPRESSION DURING THE NEXT DAY OR SO AS IT MOVES WEST-NORTHWESTWARD
AROUND 15 MPH. THERE IS A HIGH CHANCE...GREATER THAN 50
PERCENT...OF TROPICAL CYCLONE FORMATION IN THIS AREA DURING THE
NEXT 48 HOURS. INTERESTS IN THE LESSER ANTILLES SHOULD MONITOR THE
PROGRESS OF THIS SYSTEM.

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

$$
FORECASTER ROBERTS/PASCH
NNNN

It's gone far enough west that, should it develop, I think there's a better than 50/50 chance it will hit the US. The high pressure building into the northeast today will entrench itself during the week, shutting off the usual recurve-northeast conveyor.

http://moe.met.fsu.edu/cgi-bin/hwrftc2.c....

Wait until page has fully loaded, then hit "FWD" button.

A nice presentation on satellite this evening, and it is entering a region with warmer SSTs.

Boom!

http://hadar.cira.colostate.edu/ramsdis/....

The good news and the bad news about shear....

The good news: it's been inhibiting this storms ability to develop into a named system.

The bad news: this means it keeps moving farther and farther west.

http://moe.met.fsu.edu/cgi-bin/hwrftc2.c....

See sat link above.

Prediction: Storm will be upgraded to a depression at the 11PM NHC advisory, and be named Erika on the 8AM or 11AM advisories tomorrow. The giant high pressure system building onto the east coast will drive Erika into the US as at least a cat-2 hurricane, and cat-3 or stronger if driven ashore south of Cape Hatteras.

NHC has issued Discussion #1 for TS ERIKA

Quote:

WTNT41 KNHC 012047
TCDAT1
TROPICAL STORM ERIKA DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062009
500 PM EDT TUE SEP 01 2009

And in the Advisory #1:

Quote:

ERIKA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 9 MPH...15 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT COUPLE
OF DAYS. ON THIS TRACK THE CENTER OF ERIKA IS EXPECTED TO REMAIN
TO THE NORTHEAST OF THE LEEWARD ISLANDS.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/HR...WITH HIGHER
GUSTS. SOME SLOW STRENGTHENING IS FORECAST DURING THE NEXT COUPLE
OF DAYS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105 MILES...165 KM
FROM THE CENTER.

THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE RESERVE
RECONNAISSANCE AIRCRAFT IS 1007 MB...29.74 INCHES.

Rare case of a storm named without going through Depression status first.

I've never seen it before, either, but I'm no pro. I've just got good web links.

Long-range models are started to gel on a Hugo-style cat-4 heading toward the Carolinas.

What the ****? I had my fill of Hugo-style hurricanes from the master of Hugo-style hurricanes himself - Hugo.

Time to start prepping Caledo. Best of luck to those who may be in the way of this soon to be hurricane.

http://www.easternuswx.com/bb/index.php?....

Nice write up on Erica

We're tracking this on a couple of different models, with wildly divergent projected paths.

Quote:

Model forecasts for ERIKA’s path are highly divergent. This is not unexpected given that the storm is newly formed and has a weak
circulation – the models generally find it difficult to characterize new, weak storms. Further, the models seem to have expected ERIKA to
take on a northerly component to its track while ERIKA has remained stubbornly drifting almost due west. Figure 1 highlights the problem
– it shows the early cycle and late cycle model forecasts for ERIKA and the divergence between the model sets is clear. The early cycle
models typically have a simplified view of the atmosphere whereas the late cycle models generally include ‘full physics’, with a fully
simulated view of the atmosphere. Given that the late cycle models are more complex and take longer to run they are available later in time
than the early cycle model forecasts (hence the late and early nomenclature) and generally lag the output from the early cycle models. In the
case of figure 1, the late cycle models are from 9/2/09 0600GMT whereas the early cycle models are as of 9/2/09 1200GMT. The early cycle
models have responded to ERIKA’s sustained westward motion whereas the late cycle models have not yet had time to adjust to the
movement. We expect that when the late cycle models update with the latest location, they will fall more in line with the early cycle models;
however, the divergence will still remain.

In general, ERIKA is being prevented from moving much to the north by a frontal boundary system extending from the Gulf of Mexico, over
Florida and into the Atlantic (this is clearly seen as a line of high shear in figure 2 below). Given that the forecasts are divergent the NHC,
and ourselves, have low confidence in any particular model at this time. However, there are three basic scenarios we foresee:
1. ERIKA maintains a westerly track, taking the storm over the Leeward Islands and towards Puerto Rico and Hispaniola. Medium
term, this has the potential to take ERIKA into the Caribbean Sea, towards Jamaica. In the longer term, this track could bring
ERIKA towards the Yucatan Peninsula or the Gulf of Mexico. The required condition for this scenario to occur would be for the
frontal system in place over the Gulf/Florida area to persist. We estimate this is a low likelihood scenario given that it is presently
not shown in any model forecast. Historically, however, storms with ERIKA’s approximate location and direction have a roughly
50/50 chance of taking this path. We cannot, at this time, rule this scenario out.
2. ERIKA slowly meanders with a slight northerly component, approaching or skirting the Bahamas in 3-5 days. This track
represents the current NHC consensus forecast and is in broad agreement with the majority of the early cycle models. This track
requires the frontal system to break down over the next 3-5 days. Long term, this scenario has the potential to bring ERIKA
towards Florida or the Carolinas although the most likely outcome for this scenario is ERIKA turning out into the open Atlantic
before reaching the US coast (possibly tracking between the US and Bermuda). A variant of this scenario is the most likely
outcome.
3. ERIKA picks up an increased northerly component and moves off into the open Atlantic without bothering the Bahamas or the US
coast. This scenario is essentially the most ‘rightward’ case of scenario 2 and is currently the general consensus of the late cycle
models; it requires the frontal system to move/breakdown in the near future. We consider this scenario to be relatively low in
likelihood.

This is from the Willis Re Hurricane Commentary Bulletin, 02 September 2009. Wish I could post the entire PDF, but it's larger than 100KB

This is cat-5 season for the western Caribbean and Gulf; if Erika runs west underneath Hispaniola, watch out.

Cool visible loop: PR is like a fork in the road.

http://www.ssd.noaa.gov/goes/flt/t2/flas....

"Long-range models are started to gel on a Hugo-style cat-4 heading toward the Carolinas."


Holy ****--Hugo was awful. When is it supposed to get here?

There is considerable uncertainty about Erika which will not be resolved until early next week.
Dr. Jeff Masters' blog on www.wunderground.com:
http://www.wunderground.com/blog/JeffMas....