WPAC : TROPICAL DEPRESSION MIRINAE (23W)

[metenthusiast]

We here in the Philippines are sooooooo doomed...

Well, I wouldn't exactly put it that way. If you're a Filipino, you'd know what I mean. We're as hard-bitten and resilient as they come.

[cycloneye]

1500z Prognostic Reasoning by JTWC

This came out well after the 1500z warning from JTWC was released.Those friends in Luzon read carefully,and Jeff this may help you decide where to go and wait for Mirinae.

WDPN32 PGTW 271500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 23W (MIRINAE)
WARNING NR 07//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
A. TROPICAL STORM (TS) 23W (MIRINAE) HAS CONTINUED TO TRACK
WEST-NORTHWESTWARD OVER THE PAST 12 HOURS AND HAS STEADILY
INTENSIFIED TO 45 KNOTS. DVORAK ESTIMATES FROM PGTW, KNES AND RJTD
CURRENTLY SUPPORT A WIDE RANGE OF INTENSITIES- FROM 35 TO 55 KNOTS.
HOWEVER, (SUBJECTIVE) ANALYSIS OF A 271035Z TMI 85H MICROWAVE IMAGE
REVEALS A DEVELOPING MICROWAVE EYE, WHICH IS TYPICAL OF SYSTEMS 45
KNOTS OR GREATER. POLEWARD OUTFLOW HAS ALSO IMPROVED AS THE SYSTEM
BEGINS TO INTERACT WITH A PASSING LONGWAVE TROUGH TO THE NORTH.
3. FORECAST REASONING
A. THE PEAK INTENSITY HAS BEEN DECREASED FROM 115 KNOTS TO 100
KNOTS OVER THE PAST 2 FORECASTS IN ORDER TO BETTER REFLECT THE
INTENSITY GUIDANCE.
B. THE SYSTEM WILL CONTINUE TO INTENSIFY AS IT TRACKS GENERALLY
WEST TO NORTHWESTWARD OVER THE NEXT 5 DAYS. IN THE SHORT TERM, THE
TROUGH MENTIONED IN PARA 2.A. WILL PROVIDE A BRIEF PERIOD OF
ENHANCED POLEWARD OUTFLOW BEFORE IT WEAKENS AND PULLS OUT OF THE
TROPICS. AFTER WHICH, THE MID-LATITUDE PATTERN APPEARS TO BECOME
MORE ZONAL, WHICH WILL ALLOW THE MID TO UPPER LEVEL SUBTROPICAL
RIDGE TO STRENGTHEN TO THE NORTH OF THE STORM. ALL THE WHILE THE
STORM WILL REMAIN SOUTH OF THE RIDGE AXIS AND UNDER THE STEERING
INFLUENCE OF MODERATE EASTERLIES. MODEL GUIDANCE IS IN VERY GOOD
AGREEMENT WITH THIS FORECAST TRACK. WBAR, CONSISTENTLY A NORTHERN
OUTLIER, HAS EVEN COME INTO LINE WITH THE REST OF THE PACKING.
C. BY TAU 72 THE SYSTEM WILL BE ABOUT FOUR DEGREES TO THE EAST
OF LUZON IN THE PHILIPPINE SEA AT ITS PEAK INTENSITY. LANDFALL IS
EXPECTED JUST BEFORE TAU 96. THE SYSTEM WILL SLOW AND WEAKEN AS IT
CROSSES LUZON, BUT WILL EMERGE INTO THE SOUTH CHINA SEA WITH THE
ENVIRONMENTAL INGREDIENTS IN PLACE FOR RE-INTENSIFICATION. //
NNNN

[ozonepete]

I think MIRINAE is moving West right now...Not sure if the sat loops are playing tricks on me but that's what I'm seeing...........

I don't think you're seeing things - it looks like it is moving west again to me too. It wouldn't surprise me anyway, since it looks like the STR behind it is starting to build back to the west and the ridge to the north is building in and blocking much northward movement. We'll have to wait for the next couple of location fixes.

[metenthusiast]

I think MIRINAE is moving West right now...Not sure if the sat loops are playing tricks on me but that's what I'm seeing...........

I don't think you're seeing things - it looks like it is moving west again to me too. It wouldn't surprise me anyway, since it looks like the STR behind it is starting to build back to the west and the ridge to the north is building in and blocking much northward movement. We'll have to wait for the next couple of location fixes.

The orange ones are the STR and it's forcing the system on a more westward track.

[oaba09]

I think MIRINAE is moving West right now...Not sure if the sat loops are playing tricks on me but that's what I'm seeing...........

I don't think you're seeing things - it looks like it is moving west again to me too. It wouldn't surprise me anyway, since it looks like the STR behind it is starting to build back to the west and the ridge to the north is building in and blocking much northward movement. We'll have to wait for the next couple of location fixes.

If this continues, JMA's forecast will be the one that will most likely happen am I right? Do you think the STR will be strong enough to make MIRINAE move south of JTWC's forecast?

[dexterlabio]

^ Haha but jtwc still reports a 45kts intensity. for a system to have an eye-like feature, it has to reach almost typhoon intensity, maybe 55kts or more. Maybe it still appears to be weaker because of its size and soon-to-be-develop circulation.

When a storm is developing rapidly, as this now appears to be doing, the agencies can't keep up with it sometimes. Remember JTWC reports every 6 hours with intermediate every 3 hours. A eye can form within an hour or two in some cases. So it could be that Mirinae got to 55 knots or even higher since the JTWC issued that last advisory.

That happens also with JMA and yes the National Hurricane Center here in the U.S.

oh. that's why maybe jtwc will post the increase in intensity later tonight or tomorrow morning.

yeah. it seems that the storm is tracking on a very straight westward manner. i think the thick clouds in the center is what we call a CDO. its circulation is becoming more defined, in my opinion, and it seems that there will be a good radial outflow for this system soon.

[Derek Ortt]

well of course STIPS has decreased. persistence is a MAJOR factor in statistical models. The fact that JTWC has been on par with IMD with this storm (a 35KT storm having a well defined eye on microwave imagery) speaks volumes

I can say from looking at this that the storm appears to be a T 3.5 and the intensity should be 55, not 45KT. That would get STIPS much higher

So continue preparing for 115-125KT if you are in the Philippines

[ozonepete]

"A. THE PEAK INTENSITY HAS BEEN DECREASED FROM 115 KNOTS TO 100
KNOTS OVER THE PAST 2 FORECASTS IN ORDER TO BETTER REFLECT THE
INTENSITY GUIDANCE."


Interesting. They don't say why. I suspect one reason is that large area of dry air to the northwest. That could really hinder development if any of it gets ingested.

[Derek Ortt]

also, on the nighttime visible, the center is closer to 16N right now. Still moving quickly to the WNW

[oaba09]

well of course STIPS has decreased. persistence is a MAJOR factor in statistical models. The fact that JTWC has been on par with IMD with this storm (a 35KT storm having a well defined eye on microwave imagery) speaks volumes

I can say from looking at this that the storm appears to be a T 3.5 and the intensity should be 55, not 45KT. That would get STIPS much higher

So continue preparing for 115-125KT if you are in the Philippines

After ketsana and parma, trust me, people are already paranoid whenever a storm comes...This is actually a good thing because the more paranoid the people are, the preparations they make for an incoming system......

[Derek Ortt]

"A. THE PEAK INTENSITY HAS BEEN DECREASED FROM 115 KNOTS TO 100
KNOTS OVER THE PAST 2 FORECASTS IN ORDER TO BETTER REFLECT THE
INTENSITY GUIDANCE."


Interesting. They don't say why. I suspect one reason is that large area of dry air to the northwest. That could really hinder development if any of it gets ingested.

see my post above. It is because they are improperly analyzing the intensity

[ricmood]

I think MIRINAE is moving West right now...Not sure if the sat loops are playing tricks on me but that's what I'm seeing...........

I don't think you're seeing things - it looks like it is moving west again to me too. It wouldn't surprise me anyway, since it looks like the STR behind it is starting to build back to the west and the ridge to the north is building in and blocking much northward movement. We'll have to wait for the next couple of location fixes.

The orange ones are the STR and it's forcing the system on a more westward track.

Based on this picture. The STR extends up to the middle of Visayas. Is it possible that the storm will track more SW hitting visayas, like what PAGASA saying?

[oaba09]

Based on this picture. The STR extends up to the middle of Visayas. Is it possible that the storm will track more SW hitting visayas, like what PAGASA saying?

I don't think it will be that strong....I expect a southern luzon landfall rather than a central luzon one......

[metenthusiast]

well of course STIPS has decreased. persistence is a MAJOR factor in statistical models. The fact that JTWC has been on par with IMD with this storm (a 35KT storm having a well defined eye on microwave imagery) speaks volumes

I can say from looking at this that the storm appears to be a T 3.5 and the intensity should be 55, not 45KT. That would get STIPS much higher

So continue preparing for 115-125KT if you are in the Philippines

After ketsana and parma, trust me, people are already paranoid whenever a storm comes...This is actually a good thing because the more paranoid the people are, the preparations they make for an incoming system......

Right about that! I was just wondering whether Saturday would be the "Day"?

[ozonepete]

well of course STIPS has decreased. persistence is a MAJOR factor in statistical models. The fact that JTWC has been on par with IMD with this storm (a 35KT storm having a well defined eye on microwave imagery) speaks volumes

I can say from looking at this that the storm appears to be a T 3.5 and the intensity should be 55, not 45KT. That would get STIPS much higher

So continue preparing for 115-125KT if you are in the Philippines

I assume you're no big fan of IMD. As far as STIPS, are you saying that a 10 knot decrease in the initialization is what produced the 15 knot decrease 4 days out?

[metenthusiast]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 27 OCT 2009 Time : 140000 UTC
Lat : 15:43:38 N Lon : 141:43:18 E


CI# /Pressure/ Vmax
3.5 / 984.4mb/ 55.0kt


Final T# Adj T# Raw T#
(3hr avg)
3.4 3.5 3.5

Latitude bias adjustment to MSLP : +0.4mb
Center Temp : -77.6C Cloud Region Temp : -74.5C
Scene Type : UNIFORM CDO CLOUD REGION

[ozonepete]

Right about that! I was just wondering whether Saturday would be the "Day"?

Yes. Looks like Saturday morning your time right now. (2009-10-31 00Z)

[drdavisjr]

So continue preparing for 115-125KT if you are in the Philippines

Derek, are you saying this could be a super typhoon at landfall?

[dexterlabio]

I'll just have to wait for tomorrow's forecast. There is still a variation for all the predictions to the track and intensity as of the mean time. Maybe they will come up with a better and unified solution tomorrow afternoon. Haha.

[metenthusiast]

Right about that! I was just wondering whether Saturday would be the "Day"?

Yes. Looks like Saturday morning your time right now. (2009-10-31 00Z)

Thanks! I guess I'd better call the dialysis clinic and re-schedule for Friday.