Hurricane in Western Caribbean?

[cycloneye]

[Blown Away]

I think we are moving closer to "Code Yellow" and possible Invest status.
http://www.ssd.noaa.gov/goes/east/tatl/loop-avn.html

[Ivanhater]

Just looking at the latest run of the gfs. It has changed its tune somewhat by showing more ridging in the gulf then before at the same time the Euro is showing the hurricane in the gulf

[wxman57]

Be wary of the 06Z and 18Z runs of the GFS. The 00Z run was significantly different as far as the 500mb pattern. 12Z is in up to 120hrs now. Not far enough yet, though it doesn't show any ridge in the Gulf, just a trof digging into TX and the western Gulf and an uper low SW of Jamaica.

[Blown Away]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
10 AM EDT SUN OCT 18 2009

FRI-SAT...NEXT UPPER TROUGH PROGGED TO DIG INTO THE MS RIVER VALLEY.
MODEL CONSISTENCY WITH TROUGH AMPLITUDE SUGGESTS ANOTHER COLD FRONT
WILL TRAVERSE SWIFTLY DOWN THE FLORIDA PENINSULA AT THE END OF THE
FORECAST PERIOD. MOISTURE ADVECTION AHEAD OF FRONT APPEARS
SUFFICIENT FOR SCATTERED CONVECTION AS EARLY AS FRIDAY...WITH
PREFRONTAL BAND OF SHOWERS/STORMS CROSSING THE REGION SATURDAY.

It seems this potential system will just miss the trough the NWS is talking about and maybe that leaves a building ridge? I usually go w/ climatology and expect any system in the W Caribbean that is moving northward to track between SFL and Hispaniola, but a track towards the EGOM would not surprise me at all.

[wxman57]

12Z GFS still coming in. Here's the 126hr mid-level steering streamlines for next Friday. Doesn't indicate a Gulf threat. As I type this, the 156hr map is in, too. Same flow pattern. Ridge same place over southern MX.

[wxman57]

144hr steering in. Still no indication of east Gulf ridge. It's over southern MX. Would be hard for it to reach FL with this flow pattern.

[Blown Away]

Wxman, by next Friday this potential system wouldn't be out of the Caribbean per the EURO, so can you conclude no EGOM threat based on that chart? Looking at the EURO, it seems to move this low N towards Jamaica then WNW towards W tip of Cuba, then N into the EGOM around day 10. So maybe the ridge you are showing is what moves this low N towards Jamaica then maybe that ridge breaks down and allows this system to move into the EGOM? Am I way off??

[cycloneye]

Anyone knows if JB has said something about this?

[wxman57]

:uarrow:
Wxman, by next Friday this potential system wouldn't be out of the Caribbean per the EURO, so can you conclude no EGOM threat based on that chart?

The flow would have to change significantly 2 days beyond the chart I posted. 162hr valid midnight Saturday night is in - high not budging from southern MX. Westerly flow all across Gulf, still. Of course, the assumption is IF this GFS forecast is correct, then no Gulf threat indicated yet.

[Ivanhater]

The ridging on the 06z gfs was around the 216 hour time frame (when the Euro was showing this getting in the gulf), The Euro was showing the trough at the 144 time frame bypassing it.

[wxman57]

168hr GFS in. Ridge not moving yet. And beware that 06Z GFS - it was a complete pattern change across the Gulf from the 00Z.

[jinftl]

NWS Austin talking about remnants of Rick moving through the end of the week, followed by a cool and dry weekend. Certainly doesn't sound like a summertime ridging pattern that would push a system west. A northwesterly flow of cool dry air across texas is not going to bring any possible system in that direction.

THE CHANCE FOR SHOWERS WILL CONTINUE WEDNESDAY NIGHT THRU FRIDAY
EVENING. TROPICAL PACIFIC MOISTURE ASSOCIATED WITH THE REMNANTS OF
PACIFIC HURRICANE RICK WILL STREAM EASTWARD ACROSS TEXAS THURSDAY
AND FRIDAY IN ADVANCE OF AN UPSTREAM UPPER LEVEL TROF. THE COOL
AIRMASS AT THE SFC WILL BE OVERRUN BY THE TROPICAL PACIFIC
MOISTURE WHICH WILL RESULT IN ELEVATED SHOWERS AND CLOUDY SKIES
THURSDAY AND FRIDAY. THIS WILL KEEP AFTERNOON TEMPS IN THE 70S.

THE AXIS OF THE AFOREMENTIONED UPPER LEVEL TROF WILL FINALLY PUSH
SOUTHEAST ACROSS SOUTH CENTRAL TEXAS FRIDAY NIGHT BRINGING AN END
TO OUR RAIN CHANCES. THE UPCOMING WEEKEND WILL MOSTLY CLEAR AND
MILD WITH A DRY NORTHWEST FLOW ALOFT.

[wxman57]

180hr GFS in. It is showing the ridge over southern MX and the BoC building a bit NE. But this wouldn't open the Gulf up, it would move anything in the western Caribbean W-WSW into Central America.

By the way, I just plotted the Saturday evening GFS 500mb (10 meter intervals) and the same EC 500mb heights on the same map. They're almost exact opposites. Where the GFS has the big ridge, the Euro has a big upper low. Let's just say there's not much agreement there.

[Ivanhater]

180hr GFS in. It is showing the ridge over southern MX and the BoC building a bit NE. But this wouldn't open the Gulf up, it would move anything in the western Caribbean W-WSW into Central America.

Something to watch for sure. How is this compared to yesterdays 12z GFS run? Will be interesting to see if the Euro changes its tune. It has been the best this year. Given the time frame we are looking at, I suspect things will change.

[cycloneye]

A surface low has been added to the 12z surface analysis.



http://www.opc.ncep.noaa.gov/UA.shtml

[wxman57]

That surface low is quite common in the region, particularly very early or pre-season and late season, as the ITCZ passes through. 12Z GFS run today has a ridge across the Gulf at 228hrs - wider than the 00Z run, pretty much blocking it off from anything entering from the Caribbean. So the battle is on between the GFS and EC.

[wxman57]

Anyone knows if JB has said something about this?

He's all over it as a possible development. Not saying it's going to blast the East U.S. Coast and New England - YET - though.

[Ivanhater]

Just on a side note. The gfs was picking up on this a couple days ago. A hurricane forming in the western Caribbean moving into the gulf. The 12z Euro will be interesting

[wxman57]

Just on a side note. The gfs was picking up on this a couple days ago. A hurricane forming in the western Caribbean moving into the gulf. The 12z Euro will be interesting

It was forecasting a big low in the Gulf then in the Caribbean at 384 hours a few days ago. That's near the end of October not the 24-25th.