2014 EPAC Season

[cycloneye]

The main threat if this forms will be the copious rains it will send to Mexico.

[hurricanes1234]

From the 4:05 May 5 discussion at NHC:

THE 18 UTC GFS INITIALIZES WELL WITH THE LOW PRES NEAR 09N1112W
BUT QUICKLY SHOWS THIS LOW BECOMING ABSORBED INTO A DEEPER LOW
THAT WILL EMERGE OUT OF THE CONVECTIVE MASS FARTHER EAST NEAR
11N105W TOMORROW. THIS COULD BE AN INDICATION THAT THE WESTERLY
SHEAR AHEAD OF THE APPROACHING TROUGH WILL LIMIT THE FURTHER
DEVELOPMENT OF THE WESTERN MOST LOW. THE UKMET AND TO A LESSER
EXTENT THE ECMWF FAVOR THE DEVELOPMENT OF THE WESTERN LOW
THROUGH THE NEXT 48 HOURS. THE ECMWF COMES MORE INTO AGREEMENT
WITH THE GFS POSITION THEREAFTER SHOWING THE EASTERN LOW
DRIFTING N TO NE TOWARD THE CENTRAL COAST OF MEXICO THROUGH MID
WEEK. THERE REMAIN SIGNIFICANT DIFFERENCES IN INTENSITY HOWEVER
BY THAT TIME BETWEEN THE TWO MODELS WITH THE GFS MUCH DEEPER.
THIS IS LIKELY DUE TO THE GFS SHOWING MINIMAL SHEAR ACROSS THE
EASTERN MOST LOW. THE OFFICIAL FORECAST FOLLOWS THE GFS TREND
FOR DEVELOPMENT AND POSITION BUT WITH A NOD TO THE ECMWF IN
INTENSITY FOR LATER PERIODS.

[Yellow Evan]

The main threat if this forms will be the copious rains it will send to Mexico.

Even if it does not form, IMO it could still be a bit of a flooding threat to MX.

[cycloneye]

From the 4:05 May 5 discussion at NHC:

THE 18 UTC GFS INITIALIZES WELL WITH THE LOW PRES NEAR 09N1112W
BUT QUICKLY SHOWS THIS LOW BECOMING ABSORBED INTO A DEEPER LOW
THAT WILL EMERGE OUT OF THE CONVECTIVE MASS FARTHER EAST NEAR
11N105W TOMORROW. THIS COULD BE AN INDICATION THAT THE WESTERLY
SHEAR AHEAD OF THE APPROACHING TROUGH WILL LIMIT THE FURTHER
DEVELOPMENT OF THE WESTERN MOST LOW. THE UKMET AND TO A LESSER
EXTENT THE ECMWF FAVOR THE DEVELOPMENT OF THE WESTERN LOW
THROUGH THE NEXT 48 HOURS. THE ECMWF COMES MORE INTO AGREEMENT
WITH THE GFS POSITION THEREAFTER SHOWING THE EASTERN LOW
DRIFTING N TO NE TOWARD THE CENTRAL COAST OF MEXICO THROUGH MID
WEEK. THERE REMAIN SIGNIFICANT DIFFERENCES IN INTENSITY HOWEVER
BY THAT TIME BETWEEN THE TWO MODELS WITH THE GFS MUCH DEEPER.
THIS IS LIKELY DUE TO THE GFS SHOWING MINIMAL SHEAR ACROSS THE
EASTERN MOST LOW. THE OFFICIAL FORECAST FOLLOWS THE GFS TREND
FOR DEVELOPMENT AND POSITION BUT WITH A NOD TO THE ECMWF IN
INTENSITY FOR LATER PERIODS.

Two more interesting paragraphs.

A BURST OF CONVECTION FLARED NEAR THE CENTER OF THE 1010 MB LOW
PRES CENTER NEAR 09N112W OVER THE PAST COUPLE OF HOURS...BUT HAS
SINCE SUBSIDED. THE SPORADIC CONVECTION NEAR THIS LOW IS BEING
SUPPORTED BY A NEGATIVELY TILTED SHORT WAVE TROUGH IN THE MID TO
UPPER LEVELS OF THE ATMOSPHERE SITUATED TO THE NORTHWEST OF THE
SURFACE LOW. ALTHOUGH THIS IS LIFTING NE AND OUT OF THE
AREA...ADDITIONAL CONVECTION IS LIKELY TO FLARE OVERNIGHT NEAR
THE CENTER AND MAY INCREASE MORE TOMORROW AHEAD OF A MORE
SIGNIFICANT LONG WAVE TROUGH APPROACHING THE AREA FROM THE WEST.
PROVIDED THIS DOES NOT IMPOSE SIGNIFICANT WESTERLY SHEAR OVER THE
DEVELOPING CONVECTION.

FARTHER EAST...THE CONVECTION IS MORE INTENSE...PERSISTENT AND
WIDESPREAD BUT AS YET THERE IS NO WELL DEFINED LOW LEVEL CENTER.
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION PERSISTS FROM
05N TO 10N BETWEEN 95W AND 105W. THE CONVECTION AS BEEN PULSING
FOR THE PAST SEVERAL DAYS IN THIS AREA...AIDED BY FAVORABLE JET
DYNAMICS ALOFT. IT HAS INCREASED TODAY WITH THE HELP OF
CONSIDERABLE LOW LEVEL CONVERGENCE SUPPLIED BY THE RECENT GULF
OF TEHUANTEPEC GALE EVENT. ASCAT DATA FROM SEVERAL HOURS AGO
INDICATED 20 T0 25 KT WINDS REACHING AS FAR AS 12N100W. ASCAT
SATELLITE DATA AND TOGA-TAO OBSERVATIONS FAR SOUTH SHOW LIGHT
MOSTLY SE TO S WINDS...POSSIBLY INFLUENCED BY THE DEVELOPING LOW
NEAR 09N112W. WITH THIS FLOW PATTERN THIS IS NO CLEAR MONSOON
TROUGH AT LEAST FOR THE TIME BEING EAST OF 100W.

[hurricanes1234]

It looks like the only problem for this would be possible westerly shear, according to the discussion.

[Yellow Evan]

It looks like the only problem for this would be possible westerly shear, according to the discussion.

That and if two centers form and interact with each other, much like Bud 94. Not likely though.

This situation is much more complex than I realized. It really needs to consolidate if it wants to form. Tbh I think it is slightly less likely now, but I still would not rule it out. This genesis is somewhat 80's like.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[cycloneye]

The 16:05 UTC discussion.

TWO AREAS OF ACTIVE CONVECTION ARE EMBEDDED WITHIN THE MONSOON
TROUGH. THE FIRST AREA IS ASSOCIATED WITH A SURFACE LOW CENTERED
NEAR 09N112W. THE SECOND AREA WAS ASSISTED BY SPEED CONVERGENCE
INTO THE MONSOON TROUGH FROM THE PREVIOUS GAP WIND EVENT. THIS
AREA HAS A WELL DEFINED MID LEVEL CIRCULATION. THE FORECAST OVER
THE NEXT COUPLE OF DAYS HAS A LOT OF UNCERTAINTY. THE GENERAL
CONSENSUS OF THE GUIDANCE OVER THE PAST COUPLE OF DAYS IS FOR
THESE AREAS OF ENHANCED VORTICITY TO MERGE...WITH THE SURFACE
LOW SHIFTING N THEN NE WHILE INTERACTING WITH AN UPPER LEVEL
TROUGH. HOWEVER...THERE ARE SIGNIFICANT DIFFERENCE BETWEEN
GUIDANCE WITH THE STRENGTH OF THE LOW PRESSURE WHICH IS RELATED
TO THE POSITION OF THE UPPER TROUGH IN RELATION TO THE SURFACE
LOW AND THE RESULTANT SHEAR. THE TREND FOR THE ECMWF AND UKMET
HAS BEEN TOWARD A WEAKER LOW WHILE THE GFS HAS A MUCH STRONGER
LOW. THE OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE GFS TREND
FOR DEVELOPMENT AND POSITION BUT WITH A NOD TO THE ECMWF/UKMET
FOR INTENSITY FOR LATER PERIODS.

[Yellow Evan]

I hate to say it, but I think it's running out of time. The GFS continues to insist on a weak TS into MX though.

[hurricanes1234]

It is running out of time. I can only see this becoming an Alvin 2013 at most. Shear is expected to start soon.

[Yellow Evan]

It is running out of time. I can only see this becoming an Alvin 2013 at most. Shear is expected to start soon.

Alvin 13? This is likely gonna hit land. Also, the shear pretty much has always been there.

[hurricanes1234]

It is running out of time. I can only see this becoming an Alvin 2013 at most. Shear is expected to start soon.

Alvin 13? This is likely gonna hit land. Also, the shear pretty much has always been there.

I mean in terms of strength (less than 60 knots).

[cycloneye]

Is very broad the complex area that covers this and that is why is having a hard time organizing right now.

[Yellow Evan]

Is very broad the complex area that covers this and that is why is having a hard time organizing right now.

http://oi57.tinypic.com/2z5ryph.jpg

I think the center has become slightly better defined though. If shear was low, yes I think this would form, but right now it is moderate to strong, so it's kinda up in the air IMO.

[hurricanes1234]

Let's see if the shear relaxes in this area. But that would be bad for Mexico if it makes landfall.

[hurricanes1234]

Latest discussion:


Eastern Pacific Tropical Weather Discussion


000
AXPZ20 KNHC 052116
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAY 05 2014

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2130 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM 04N83W TO LOW PRES NEAR 05N90W
TO 10N102W TO ANOTHER AREA OF LOW PRES NEAR 10N112W TO 08N120W.
WHERE LOW LEVEL WINDS SUGGEST A TRANSITION TO ITCZ FROM 08N120W
TO 05N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 360 NM S
OF TROUGH BETWEEN 93W AND 108W...AND WITHIN 120 NM EITHER SIDE
OF TROUGH BETWEEN 109W AND 113W...AND WITHIN 180 NM N OF THE
ITCZ BETWEEN 124W AND 129W.

...DISCUSSION...

TWO AREAS OF ACTIVE CONVECTION ARE EMBEDDED WITHIN THE MONSOON
TROUGH. THE FIRST AREA IS ASSOCIATED WITH A SURFACE LOW CENTERED
NEAR 10N112W. THE SECOND AREA WAS ASSISTED BY SPEED CONVERGENCE
INTO THE MONSOON TROUGH FROM A WANING GAP WIND EVENT IN THE GULF
OF TEHUANTEPEC. THIS AREA RETAINS A WELL DEFINED MID LEVEL
CIRCULATION....THOUGH LATE DAY VISIBLE SATELLITE IMAGERY
SUGGESTS CYCLONIC TURNING AT THE LOW LEVELS. THE FORECAST FOR
THIS SYSTEM REMAINS QUITE UNCERTAIN OVER THE NEXT FEW DAYS. THE
GENERAL CONSENSUS OF THE GUIDANCE OVER THE PAST COUPLE OF DAYS
IS FOR THESE AREAS OF ENHANCED VORTICITY TO MERGE...WITH THE
SURFACE LOW SHIFTING N THEN NE WHILE INTERACTING WITH AN UPPER
LEVEL TROUGH CURRENTLY ALONG 125W WHICH IS FORECAST TO SWING
EASTWARD.

. THERE ARE SIGNIFICANT DIFFERENCE BETWEEN THE GLOBAL MODELS
WITH REGARD TO THE STRENGTH OF THE LOW PRESSURE AREA. THE THE
TREND FOR THE ECMWF AND UKMET HAS BEEN TOWARD A WEAKER LOW
FURTHER TO THE WEST WHILE THE GFS HAS A MUCH STRONGER LOW
TRACKING FURTHER EAST. THE OFFICIAL HIGH SEAS FORECAST WILL
CONTINUE TO FOLLOW THE GFS AND ITS ENSEMBLES FOR DEVELOPMENT AND
POSITION BUT WITH A NOD TO THE ECMWF/UKMET FOR INTENSITY. AN
AREA OF 20-25 KT SW WINDS IS FORECAST TO DEVELOP WITHIN 240 NM
IN THE SE SEMICIRCLE OF THE LOW PRES AREA AS IT TRACKS SLOWLY
NE.

[JonathanBelles]

I took a quick look at this today in my first blog of the season. It may become our first deepening low, but all I expect is rainy weather for Mexico. Southeast weather forecast discussed as well at:

http://www.jonathanbelles.com
More frequent updates on twitter @JonathanBelles

[Yellow Evan]

Let's see if the shear relaxes in this area. But that would be bad for Mexico if it makes landfall.

If anything, intensification could be better for MX since it'll be more likely to consolidate, which means the rain is less widespread. Unless it remains attached to the ITCZ.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[Yellow Evan]

Looks better this evening. The center looks better defined, and outflow has improved. Not all hope is lost.

[hurricanes1234]

Only a short paragraph from the 10:05 UTC discussion:

HOWEVER...THERE ARE SIGNIFICANT DIFFERENCE BETWEEN GUIDANCE WITH
THE STRENGTH AND SPEED OF THE LOW PRESSURE WHICH IS RELATED TO
THE POSITION OF THE UPPER TROUGH IN RELATION TO THE SURFACE LOW
AND THE RESULTANT SHEAR. CURRENTLY THE UPPER TROUGH EXTENDS FROM
THE N BAJA CALIFORNIA PENINSULA ALONG 25N118W TO A BASE NEAR
12N132W.

I would agree with Yellow Evan, though, it's starting to get that shape. Looks good this morning, in my opinion.

[hurricanes1234]

Let's discuss what the models are hinting for development beyond 90E.