OLGA'S remnants : Discussions & Images

[HURAKAN]

Latest:


Loop shows center south of eastern Cuba near 75W.

[Ed Mahmoud]

How much of Olga or its corpse gets pulled into the weekend Super-Mondo Northeast Winter Storm?

[ronjon]

Actually, looking at the latest VIS SAT, Olga doesn't look too bad for traveling over the the island of Hispanola from east to west. The broad circulation center has maintained its integreity and the overall system convection is still there. Low level center is now back over water and direction is a pretty steady westward motion. At present, I don't see any evidence of strong shear affecting the system. We have two models, 00Z CMC and NOGAPs that move the LLC thru the Yuc straits and then NE into FL while being absorbed into a strong cold front on Saturday. Other models like GFDL meander and strengten the system off the north coast of Honduras. Shoud be interesting to see how this plays out. Latest 06Z GFS brings a lot more moisture into FL from Olga then previous runs.

[Coredesat]

There is strong shear over the system, but there is so little convection near the actual center that it's not having much of an effect other than to keep new convection from firing over the center. That and the actual center is mostly embedded in very dry air.

[wxman57]

Actually, looking at the latest VIS SAT, Olga doesn't look too bad for traveling over the the island of Hispanola from east to west. The broad circulation center has maintained its integreity and the overall system convection is still there. Low level center is now back over water and direction is a pretty steady westward motion. At present, I don't see any evidence of strong shear affecting the system. We have two models, 00Z CMC and NOGAPs that move the LLC thru the Yuc straits and then NE into FL while being absorbed into a strong cold front on Saturday. Other models like GFDL meander and strengten the system off the north coast of Honduras. Shoud be interesting to see how this plays out. Latest 06Z GFS brings a lot more moisture into FL from Olga then previous runs.

Quite an optimistic view. I see a broadening and open LLC racing westward away from the convection, clear signs of increasing westerly shear. Olga already looks like a remnant low. I can no longer find winds above 30 kts to its north. What's left of Olga may well be caught up in the trof approaching Florida over the weekend, but mostly in the form of mid and high-level moisture.

[HURAKAN]

Center pretty visible in this shot.

[Coredesat]

Quite an optimistic view. I see a broadening and open LLC racing westward away from the convection, clear signs of increasing westerly shear. Olga already looks like a remnant low. I can no longer find winds above 30 kts to its north. What's left of Olga may well be caught up in the trof approaching Florida over the weekend, but mostly in the form of mid and high-level moisture.

In addition, what convection there is has become elongated due to said westerly shear.

[wxman57]

Center pretty visible in this shot.

http://rammb.cira.colostate.edu/ramsdis ... al/176.JPG

It almost looks like that very broad open area centered on Jamaica is becoming the elongated center with a remnant vortex near 19.2/75.2 or so. That vortex appears to be moving southwestward now on the periphery of the broader low center. I.E., it's opening up and losing its LLC. Northeasterly winds across the Cayman Islands support the idea of an elongated low. Good riddance.

[gatorcane]

amazingly the structure is pretty darn good considering it has crossed mountains that are 13,000+ ft high.

You can clearly see the center now moving WSW as Wxman suggest..but convection is now starting to build on the NE side.

I don't think Olga is done yet folks. Good grief.

[Evil Jeremy]

Isn't the ridge, or whatever was keeping Olga south, moving away now?

http://www.ssd.noaa.gov/goes/east/nwatl/loop-wv.html


Also, correct me if I am reading this wrong, but if this map is true, doesn't it mean that Olga is leaving a higher shear zone right now?

http://www.ssd.noaa.gov/PS/TROP/DATA/gparm/xyrshr.gif

[Coredesat]

Shear doesn't matter if there is nothing at the mid to upper levels. Olga's LLCC (or what is left of it) has become detached from the convection, and is a low cloud swirl. All shear will do is keep new convection from firing close to the center (along with the dry air - I keep saying this, but there is a ridiculously large mass of dry air down there). And even if you do see that it's leaving an area of higher shear, 30 kt is still very strong and destructive to a tropical cyclone, especially when the direction of the shear is the opposite of the system's forward motion.

Even if the ridge moves away, the remnants of Olga will simply be absorbed into or sheared apart by the approaching front. There is nowhere in the Caribbean that is hospitable to tropical cyclone development, whether due to shear or dry air at all levels.

[Evil Jeremy]

40MPH winds at 11

[Evil Jeremy]

00
WTNT42 KNHC 121431
TCDAT2
TROPICAL STORM OLGA DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172007
1000 AM EST WED DEC 12 2007

OLGA LACKS THE CONVECTION REQUIRED OF A TROPICAL CYCLONE...AND BASED
ON VISIBLE SATELLITE IMAGERY PROBABLY ALSO LACKS A CLOSED SURFACE
CIRCULATION. HOWEVER...WE WILL HANG ON TO OLGA FOR A FEW MORE
HOURS JUST IN CASE DEEP CONVECTION RETURNS OR WEST WINDS BECOME
EVIDENT. A QUIKSCAT PASS AT 10Z...AS WELL AS SURFACE OBSERVATIONS
SUGGEST THAT THERE REMAINS A BAND OF TROPICAL STORM FORCE WINDS
JUST EAST OF THE TURKS AND CAICOS ISLANDS. THE INITIAL INTENSITY
IS SET AT 35 KT BASED ON THESE DATA.

THE VORTICITY CENTER HAS ACCELERATED...AND THE INITIAL MOTION IS
ESTIMATED TO BE 270/20. OLGA REMAINS TO THE SOUTH OF A LOW- TO
MID-LEVEL RIDGE CENTERED JUST EAST OF FLORIDA...AND THIS RIDGE
SHOULD CONTINUE TO STEER OLGA...OR ITS REMNANTS...WESTWARD FOR THE
NEXT DAY OR TWO. WITH DRY AIR AND STRONG SHEAR FORECAST OVER THE
NORTHWESTERN CARIBBEAN...SIGNIFICANT REGENERATION THERE IS NOT
EXPECTED.

THE PRIMARY THREAT FROM OLGA CONTINUES TO BE HEAVY RAINFALL AND
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES IN HISPANIOLA. SOME OF
THESE RAINS SHOULD SPREAD OVER EASTERN CUBA TODAY.


FORECAST POSITIONS AND MAX WINDS

INITIAL 12/1500Z 19.1N 75.2W 35 KT
12HR VT 13/0000Z 19.2N 77.6W 30 KT...REMNANT LOW
24HR VT 13/1200Z 19.5N 80.5W 25 KT...REMNANT LOW
36HR VT 14/0000Z 20.0N 82.7W 25 KT...REMNANT LOW
48HR VT 14/1200Z 20.5N 84.5W 25 KT...REMNANT LOW
72HR VT 15/1200Z 21.5N 86.5W 25 KT...REMNANT LOW
96HR VT 16/1200Z...DISSIPATED

$$
FORECASTER FRANKLIN/MAINELLI

[Evil Jeremy]

000
WTNT32 KNHC 121432
TCPAT2
BULLETIN
TROPICAL STORM OLGA ADVISORY NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172007
1000 AM EST WED DEC 12 2007

...OLGA WEAKENING BUT RAINS CONTINUE OVER HISPANIOLA...

AT 10 AM EST...1500 UTC...ALL TROPICAL STORM WATCHES AND WARNINGS
FOR HAITI AND THE DOMINICAN REPUBLIC HAVE BEEN DISCONTINUED.

A TROPICAL STORM WARNING REMAINS IN EFFECT FOR THE SOUTHEASTERN
BAHAMAS AND THE TURKS AND CAICOS ISLANDS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 1000 AM EST...1500Z...THE CENTER OF TROPICAL STORM OLGA WAS
LOCATED NEAR LATITUDE 19.1 NORTH...LONGITUDE 75.2 WEST OR ABOUT 75
MILES...120 KM...SOUTH OF GUANTANAMO CUBA.

OLGA IS MOVING TOWARD THE WEST NEAR 23 MPH...37 KM/HR...AND THIS
MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. THESE WINDS ARE MAINLY CONFINED TO A FEW BANDS WELL TO THE
NORTHEAST OF THE CENTER. OLGA COULD DISSIPATE AS A TROPICAL
CYCLONE LATER TODAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 345 MILES...555 KM
TO THE NORTHEAST OF THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1009 MB...29.80 INCHES.

OLGA IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL ACCUMULATIONS OF 1
TO 2 INCHES OVER THE SOUTHEASTERN BAHAMAS. RAINFALL AMOUNTS OF 2
TO 4 INCHES ARE POSSIBLE OVER EASTERN CUBA...WITH ISOLATED MAXIMUM
ACCUMULATIONS OF 8 INCHES. RAINFALL AMOUNTS OF 4 TO 6 INCHES ARE
POSSIBLE OVER HISPANIOLA...WITH ISOLATED MAXIMUM AMOUNTS OF 10
INCHES. THESE RAINS ARE EXPECTED TO PRODUCE LIFE-THREATENING FLASH
FLOODS AND MUD SLIDES IN HISPANIOLA.

REPEATING THE 1000 AM EST POSITION...19.1 N...75.2 W. MOVEMENT
TOWARD...WEST NEAR 23 MPH. MAXIMUM SUSTAINED WINDS...40 MPH.
MINIMUM CENTRAL PRESSURE...1009 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 100 PM EST FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 400
PM EST.

$$
FORECASTER FRANKLIN/MAINELLI

[wxman57]

Here are a couple of maps that might be helpful. This is the current (predicted by GFS from 06Z) mean flow (400mb-700mb) across the region. Note the large high blocking Olga to the north. By 72 hours, the front approaches the eastern Gulf and any lingering moisture is swept north and eastward. There won't be any LLC by then, though:



And here's the projected 200mb (39,000ft) flow by 3pm CST tomorrow. Note the Polar jet digging into the eastern Gulf with very strong west and northwest winds aloft over Olga's remnants. Consider that the low-mid level flow is almost directly opposite the upper-level flow and you have a recipe for tremendous shear. Olga's gone, history. No chance of redevelopment.

[Coredesat]

And here's the projected 200mb (39,000ft) flow by 3pm CST tomorrow. Note the Polar jet digging into the eastern Gulf with very strong west and northwest winds aloft over Olga's remnants. Consider that the low-mid level flow is almost directly opposite the upper-level flow and you have a recipe for tremendous shear. Olga's gone, history. No chance of redevelopment.

That's pretty much the point I was trying to get across, only with actual graphics and examples.

EDIT: Actually, your second image appears to be broken.

[wxman57]

40MPH winds at 11

That estimate seems about 10 kts too high. Discussion confirms their thoughts of Olga's demise:

OLGA LACKS THE CONVECTION REQUIRED OF A TROPICAL CYCLONE...AND BASED
ON VISIBLE SATELLITE IMAGERY PROBABLY ALSO LACKS A CLOSED SURFACE
CIRCULATION. HOWEVER...WE WILL HANG ON TO OLGA FOR A FEW MORE
HOURS JUST IN CASE DEEP CONVECTION RETURNS OR WEST WINDS BECOME
EVIDENT.

TS winds 300 miles NE of the center??? Not a characteristic of a TC.

[Coredesat]

NHC will probably kill it at 21Z unless something extraordinary happens.

[cpdaman]

well they do give it a chance for deep convection to re-develop althoug they do not sound so bullish

looks like this will be it for the year..............i think

[RL3AO]

ZOMG its going to the GOM!