EPAC Tropical Action 2012

[Srain]

I would not be surprised to see TS or Hurricane Carlotta during the day tomorrow. My hunch is there are chances of very rapid intensification for the next 48 hours before making landfall in the Gulf of Tehuantepec/S Mexico Region. Should DMAX bring deep convection near the center overnight, a Major Hurricane may not be out of the question prior to landfall, IMO.

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[phil882]

I would not be surprised to see TS or Hurricane Carlotta during the day tomorrow. My hunch is there are chances of very rapid intensification for the next 48 hours before making landfall in the Gulf of Tehuantepec/S Mexico Region. Should DMAX bring deep convection near the center overnight, a Major Hurricane may not be out of the question prior to landfall, IMO.

Forecast track by the vast majority of guidance is fairly ominous. I'm still very curious to see how this newly minted TD interacts with the increasing upper level easterly flow it may potentially face post 24 hours.

[HurricaneJosh]

Carlotta is born.

The forecast track is remarkably similar to Pauline 1997-- like, almost a carbon copy. Pauline passed just offshore of Puerto Angel when it was a Cat 4, so that the cyclone's right eyewall raked the town with winds estimated at up to 115 kt-- however, it weakened to Cat 2 (95 kt) before the official landfall a little further up the coast.

Carlotta's forecast landfall intensity is a much more modest 70 kt:

[Srain]

TC Carlotta has formed and the NHC suggests this may well be a threat to Acapulco as it skirts the Mexican Coast before slowing and drifting near the Coastline or just onshore. Carlotta is a small cyclone and RI is being mentioned during the next 48 hours. Currently NHC forecast suggest Carlotta will make landfall as an 80 mph Hurricane, but some questions remain as a ridge develops near the Baja and the track guidance has shifted a bit to the W. Carlotta may stall near or offshore and some further intiensification may be possible should it remain offshore. RECON is scheduled to investigate on Friday.

[am19psu]

Hard to ignore the Bud-like collapse in the models on Saturday afternoon.

[HurricaneJosh]

TC Carlotta has formed and the NHC suggests this may well be a threat to Acapulco as it skirts the Mexican Coast before slowing and drifting near the Coastline or just onshore. Carlotta is a small cyclone and RI is being mentioned during the next 48 hours. Currently NHC forecast suggest Carlotta will make landfall as an 80 mph Hurricane, but some questions remain as a ridge develops near the Baja and the track guidance has shifted a bit to the W. Carlotta may stall near or offshore and some further intiensification may be possible should it remain offshore. RECON is scheduled to investigate on Friday.

"TC"? What-- have we been magically transported to Oz?

Hard to ignore the Bud-like collapse in the models on Saturday afternoon.

Thanks for the buzzkill!1!

[Srain]

"TC"? What-- have we been magically transported to Oz?

A little boomer humor...

[HurricaneJosh]

A little boomer humor...

[am19psu]

A little boomer humor...

Cat 2 should start at 55 kts, you guys. Typical American snobbery.

[Srain]

WEATHER RECONNAISSANCE FLIGHTS

CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.

0915 AM EDT THU JUN 14 2012

SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)

VALID 15/1100Z TO 16/1100Z JUN 2012

TCPOD NUMBER.....12-027

I. ATLANTIC REQUIREMENTS

1. NEGATIVE RECONNAISSANCE REQUIREMENTS.

2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.

II. PACIFIC REQUIREMENTS

1. TROPICAL STORM CAROLTTA

FLIGHT ONE --TEAL 75--

A. 15/1800Z

B. AFXXX 0103E CARLOTTA

C. 15/1315Z

D. 13.9N 96.2W

E. 15/1700Z TO 15/2100Z

F. SFC TO 10,000 FT

2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.

[Ed Lizard]

Josh- confident of stronger storms making landfall later in the season, or going to do risk mitigation and go for what may be a non-major w/ Carlotta?

I will say, NHC disco language about possile RI should add some spice to the pot.

[Srain]

Beven for ftw...

THE INITIAL MOTION IS 325/8. CARLOTTA IS CURRENTLY BEING STEERED BY

A MID/UPPER-LEVEL RIDGE OVER THE WESTERN CARIBBEAN AND A SMALL

UPPER-LEVEL TROUGH SEEN IN WATER VAPOR IMAGERY TO THE WEST OF THE

CYCLONE. THE DYNAMICAL MODELS FORECAST THIS PATTERN TO PERSIST FOR

48 HR OR SO...FOLLOWED BY A MID/UPPER-LEVEL RIDGE BUILDING OVER

NORTHERN MEXICO. THIS EVOLUTION SHOULD CAUSE CARLOTTA TO MOVE

GENERALLY NORTHWESTWARD FOR 36-48 HR...FOLLOWED BY A MORE WESTWARD

MOTION. THE TRACK GUIDANCE HAS SHIFTED WESTWARD SINCE THE LAST

ADVISORY AND IS IN FAIR AGREEMENT THAT CARLOTTA SHOULD TRACK NEAR

OR ALONG THE COAST OF MEXICO FROM 36-72 HR. THE NEW FORECAST TRACK

IS ALSO SHIFTED TO THE WEST...BUT LIES ON THE EASTERN SIDE OF THE

GUIDANCE ENVELOPE. AFTER 72 HR...THE MEXICAN RIDGE IS FORECAST

TO WEAKEN AS A MID/UPPER-LEVEL TROUGH DEVELOPS OVER THE GULF OF

MEXICO. THIS SHOULD LEAVE THE CYCLONE IN AN AREA OF WEAK STEERING

CURRENTS WITH A VERY SLOW MOTION.

CARLOTTA IS CURRENTLY IN AN ENVIRONMENT OF LIGHT VERTICAL WIND SHEAR

AND OVER 30C SEA SURFACE TEMPERATURES. THESE CONDITIONS ARE

FAVORABLE FOR STRENGTHENING...AND THE INTENSITY FORECAST NOW CALLS

FOR CARLOTTA TO REACH AN INTENSITY OF 80 KT IN 48 HR. THE RAPID

INTENSIFICATION INDEX OF THE SHIPS MODEL SHOWS A 50-60 PERCENT

CHANCE OF 25-KT STRENGTHENING DURING THE NEXT 24 HR...AND ABOUT A

25 PERCENT CHANCE OF 40-KT STRENGTHENING...SO THE EARLY PART OF THE

CURRENT FORECAST COULD BE CONSERVATIVE. AFTER 48 HR...THE

INTENSITY IS LIKELY TO BE CONTROLLED BY HOW CLOSE THE CENTER IS TO

THE COAST. IF CARLOTTA MOVES INLAND...IT COULD DISSIPATE OVER THE

MOUNTAINS OF MEXICO. EVEN IF IT STAYS OFFSHORE...IT IS EXPECTED TO

BE CLOSE ENOUGH TO INTERACT WITH THE MOUNTAINS AND WEAKEN AS SHOWN

BY THE GFDL AND HWRF MODELS...AND THAT IS THE SCENARIO USED IN THE

INTENSITY FORECAST.

[HurricaneJosh]

It looks pretty nice. Not a bad IR presentation. The structure is there, I think.

[am19psu]

It looks pretty nice. Not a bad IR presentation. The structure is there, I think.

Steve might be spot on with the major by Saturday morning forecast. After that...

[HurricaneJosh]

Steve might be spot on with the major by Saturday morning forecast. After that...

Yeah. I'm not taking a chance with this one. What spooks me even more is that crappy angle of approach and the possibility of an offshore stall or about-face. Ugh. It is like a Bud redux in every respect.

[HurricaneJosh]

The 2 pm PDT advisory brings Carlotta up to 80 kt and suggests that may be conservative. The trend with the models suggests a threat to Acapulco, which-- surprisingly enough-- has been rarely impacted by hurricanes over the last 60+ years.

[wxmx]

Steve might be spot on with the major by Saturday morning forecast. After that...

Because of slow movement and downsloping wind? Easterly shear is limited, IMO, to cause such a collapse.

[wxmx]

On a related note, the farthest it can deviate to the right, the better the chances for at least part of the energy of Carlotta to cross basins and try to develop in the BoC farther away from land and hit back closer to the US, though I doubt it can get stronger than a TS there.

[PSUBlizzicane2007]

The 2 pm PDT advisory brings Carlotta up to 80 kt and suggests that may be conservative. The trend with the models suggests a threat to Acapulco, which-- surprisingly enough-- has been rarely impacted by hurricanes over the last 60+ years.

Pauline was the last big one, I think.

[wxmx]

Pauline was the last big one, I think.

...and she was a cat 1 when it crossed over the city. Only a handful of cat 1s have been recorded to have gone very close to Acapulco...Odile '84 was the closest Cat 2.

[HurricaneJosh]

OK, so Acapulco is overdue for a Cat 5? Got it!

[wxmx]

It's improving. Better structure and colder cloud tops. We'll see where this trend takes Carlotta, strength wise.

[Srain]

It's improving. Better structure and colder cloud tops. We'll see where this trend takes Carlotta, strength wise.

[Srain]

Steve might be spot on with the major by Saturday morning forecast. After that...

Meh...

TROPICAL STORM CARLOTTA DISCUSSION NUMBER 6

NWS NATIONAL HURRICANE CENTER MIAMI FL EP032012

200 AM PDT FRI JUN 15 2012

THE INNER CORE CONVECTIVE PATTERN HAS CONTINUED TO IMPROVE...AND A

SMALL BUT RAGGED CDO HAS FORMED OVER THE LOW-LEVEL CENTER. THE

INITIAL INTENSITY HAS BEEN INCREASED TO 60 KT BASED ON CONSENSUS

SATELLITE ESTIMATES OF T3.5/55 KT FROM TAFB AND SAB...AND THE

APPEARANCE OF AT LEAST HALF AN EYEWALL IN A 15/0348Z AMSU OVERPASS.

THE INITIAL MOTION ESTIMATE IS 320/09 KT. CARLOTTA REMAINS ON THE

PREVIOUS FORECAST TRACK. THE MID-LEVEL RIDGE TO THE EAST OF THE

CYCLONE IS EXPECTED TO KEEP CARLOTTA MOVING IN A NORTHWESTWARD

DIRECTION FOR THE NEXT 24 HOURS OR SO. AFTERWARDS...A BLOCKING

RIDGE IS FORECAST TO BUILD TO THE NORTH OF CARLOTTA ACROSS CENTRAL

AND NORTHERN MEXICO...WHICH SHOULD GRADUALLY FORCE THE STORM ON A

WEST-NORTHWESTWARD TRACK BY 36 HOURS...AND WESTWARD BY 48 HOURS BUT

AT A MUCH SLOWER FORWARD SPEED. AT 72 HOURS AND BEYOND...THE

BLOCKING RIDGE IS FORECAST BY ALL OF THE MODELS TO BREAK DOWN AND

GIVE WAY TO A BROAD TROUGH DROPPING SOUTHWARD FROM THE U.S.

SOUTHERN PLAINS AND NORTHWESTERN GULF OF MEXICO...WHICH WILL RESULT

IN WEAK STEERING CURRENTS. AS A RESULT...CARLOTTA IS EXPECTED TO

MEANDER NEAR OR JUST OFFSHORE OF THE SOUTHERN COAST OF MEXICO

DURING DAYS 3-5. THE GLOBAL MODELS ARE IN GOOD AGREEMENT ON THIS

DEVELOPING TRACK SCENARIO...ALTHOUGH THE GUIDANCE HAS SHIFTED

EASTWARD COMPARED TO PREVIOUS RUNS. HOWEVER...GIVEN THE LACK OF ANY

SIGNIFICANT DEEP-LAYER SOUTHERLY OR SOUTHWESTERLY STEERING FLOW

THAT WOULD FORCE CARLOTTA INLAND OVER THE HIGH MOUNTAIN RANGE OF

SOUTHERN MEXICO...THE OFFICIAL FORECAST TRACK KEEPS THE CENTER OF

CARLOTTA JUST OFFSHORE AS INDICATED IN PREVIOUS ADVISORIES.

RAPID INTENSIFICATION NOW APPEARS LESS LIKELY GIVEN THE RAGGED AND

ELONGATED APPEARANCE OF THE CDO FEATURE ALONG WITH MODEST EASTERLY

VERTICAL WIND SHEAR EXPECTED FOR THE NEXT 36 HOURS. HOWEVER...THE

CURRENT UPPER-LEVEL OUTFLOW PATTERN AND OTHER FAVORABLE OCEANIC AND

ENVIRONMENTAL FACTORS SHOULD ALLOW FOR STEADY STRENGTHENING AT A

NORMAL RATE OF AT LEAST ONE T-NUMBER PER DAY...AND THAT EXPECTATION

IS REFLECTED IN THE OFFICIAL FORECAST TRACK. IT IS POSSIBLE THAT

CARLOTTA COULD PEAK AT 85-90 KT BETWEEN THE 24- AND 36-HOUR

FORECAST PERIODS BEFORE WEAKENING BEGINS WHEN THE CYCLONE INTERACTS

WITH THE MOUNTAINOUS TERRAIN OF SOUTHERN MEXICO BY 36 HOURS. THE

OFFICIAL INTENSITY FORECAST IS A BLEND OF THE SHIPS...LGEM...

HWRF...AND FLORIDA STATE SUPERENSEMBLE MODELS.

[phil882]

Looks like I'm going to be hilariously wrong with my call for an increase in easterly shear. While there is some easterly shear (outflow is much more prominent to the west) it certainly hasn't been enough to curtail significant deepening. On the flip side... I'm somewhat surprised to see Carlotta developing a rather large eyewall, and that doesn't bode strongly for rapid intensification in the short term unless it can contract.

From a forecasting perspective, the next 24 hours will be key to see how intense Carlotta gets. Beyond that period this storm will become an increasing headache as it interacts with the high topography of Mexico. A complicating factor is the development of anomalous westerly low-level flow across the vast majority of the East Pacific. This will cause the vorticity associated with Carlotta to stall and perhaps retrograde. In addition, we may see the development of a large-scale circulation over Central America (CA) take place as anomalous easterly trade winds from a strengthening subtropical high progress westward across the Atlantic. Combine this with the anomalous westerly low level flow over the East Pacific, and you have a recipe for cyclonic shear vorticity over CA. This could be a favorable synoptic pattern to allow a gyre like disturbance to evolve.

[wxmx]

She's probably a cane now...she's pure eye . Convection is a little more symmetric and an eye is trying to pop out on IR.

[Srain]

She's probably a cane now...she's pure eye . Convection is a little more symmetric and an eye is trying to pop out on IR.

[wi_fl_wx]

Impressive microwave structure this morning. Completely symmetrical eyewall forming on the 37 GHz. I think it has a good chance to get to Cat 3 today.

[phil882]

Impressive microwave structure this morning. Completely symmetrical eyewall forming on the 37 GHz. I think it has a good chance to get to Cat 3 today.

We will probably see the eyewall contract significantly today if this occurs. I have been pretty bearish on the intensity forecast of Carlotta, but I agree that it seems to be getting better organized in a hurry.

[Srain]

Sweet...