2012 Atlantic Hurricane Season General Discussions

[srainhoutx]

The 12Z Canadian is faster moving and likely wrong, but that model also suggests a land falling Depression/Tropical Storm along the NE Mexico/Lower to Middle Texas Coastline. The Canadian also brings copious rainfall to all of Texas.

[srainhoutx]

The 12Z Euro is suggesting a broad low pressure area in the Bay of Campeche developing around hour 120 (next Wednesday).

Edit to add: The 12Z Euro is now suggesting a bit further N movement and very broad wet low pressure system basically covering the entire Western Gulf.

The attachment 06152012 12Z Euro 12zeurotropical850mbVortSLP120.gif is no longer available

The attachment 06152012 12Z Euro 12zeurotropical850mbVortSLP144.gif is no longer available

[srainhoutx]

HPC Afternoon Updated Surface Charts:

[srainhoutx]

The 12Z GFS is suggesting a bit more organized vertically stacked possible depression/Tropical Storm meandering N.

[srainhoutx]

The 12Z Canadian also suggests a more developed depression/TS approaching the Middle/Upper Texas Coast.

[srainhoutx]

The 12Z Euro suggests a broad low pressure forming in the Bay of Campeche next Thursday with multiple areas of vorticity which is common in a monsoonal trough setup.

HPC Afternoon Update:

ANY WRN GULF TROPICAL
DEVELOPMENT IS CURRENTLY FCST TO TRACK S OF THE RIO GRANDE AS PER
YDAYS NHC/HPC COORDINATION AND EXTRAPOLATION INTO DAY 7.


AN APPROACHING TROPICAL WAVE AND DEEP LAYERED MOISTURE WILL SPREAD
NORTH AND NORTHWEST ACROSS THE CARRIBEAN INTO FL/GLFMEX AND THE
CENTRAL GULF COAST THIS PERIOD WITH VERY ANOMONOUSLY HIGH PWS
VALUES IN EXCESS 0F 2.5 INCHES. ADDITIONALLY ALL GUIDANCE
INDICATES THE FORMATION OF A TROPICAL LOW IN THE SOUTHWESTERN
GLFMEX WHICH WILL SPREAD ADDITIONAL MOISTURE INTO COASTAL TX AND
ERN MEXICO BY NEXT WEEKEND. LATEST 12Z GFS AND CMC ARE MORE
AGRESSIVE WITH THIS SOLUTION. SEE NHC OUTLOOKS.

[srainhoutx]

Attention turns to the Bay of Campeche during the coming week. Guidance has been very suggestive on developing a broad low pressure within the monsoonal trough for many days. The remnants of Carlotta along with an area of disturbed weather moving out of the Western Caribbean combined with relaxing wind shear and falling pressures as well as a favorable upper air pattern providing for anticyclonic out flow are the ingredients needed in a recipe to develop a tropical disturbance. Currently a 1015mb Upper Ridge is positioned just S of Monterrey, MX. Along the EC, a trough has reached the Keys and NATL ridging is forecast to shift W into the Western Basin. Satellite imagery suggests deep tropical moisture extends from the EPAC on E into the Western N Atlantic Basin. Shear is still rather strong across the Western Caribbean and the Gulf, but all guidance forecast a relaxing of wind shear over the SW Gulf of Mexico during the middle of the coming week. With deep tropical moisture in place and such a broad surface low slowly meandering N to NNW out of the SW Gulf, daily long fetch E to SE flow will keep rainfall in the forecast most if not all of the upcoming work week. What will need to be monitored is the potential for heavy rainfall. The favored areas would be Coastal Texas/SW Louisiana and along the NE Mexican Gulf Coast. The fly in the ointment is whether a closed surface low will fully develop as the GFS has suggested or remain and open wave. The 00Z Euro for the first time has ‘sniffed’ the possibility of a closed low developing. At this time it is my hunch a broad surface low will develop within the monsoonal trough with deep tropical moisture moving inland along and E of the low pressure center which appears to be very slow to move and finally slowly slide inland in Deep S Texas/NE Mexico later next weekend/early during the week of the 25th. All bets are off should a more defined and developed closed, vertically stacked system finally form as we near next weekend.

HPC:

OVER LOWER LATITUDES... MODELS/ENSEMBLES STILL
ANTICIPATE MORE FAVORABLE CONDS FOR PSBL TROPICAL DEVELOPMENT OVER
THE SWRN GULF OF MEXICO THOUGH PERHAPS WITH SLIGHTLY SLOWER TIMING
THAN SEEN OVER THE PAST COUPLE DAYS. THE NRN GULF SYSTEM IN THE
CANADIAN IS THE ONE OUTLIER SOLN THIS CYCLE.

[srainhoutx]

There is some speculation that the sole feature involved in developing the Bay of Campeche disturbance is the weak low pressure in the Western Caribbean. The models have been rather insistent that this will be a combination of events that include left over mid level vorticty from Carlotta in the EPAC crossing the Isthmus of Tehuantepec and the Western Caribbean wave of low pressure slowly consolidating into a broad surface low embedded with the monsoonal trough. The 12Z GFS suggests this today as well.

The attachment 06172012 12Z GFS gfs_wnatl_108_850_vort_ht.gif is no longer available

[Portastorm]

I can find no better synopsis of what the week ahead may have for us in southeast/south central Texas than here on the KHOU forum. Outstanding summaries from srainhoutx! Great work, sir.

[ticka1]

I can find no better synopsis of what the week ahead may have for us in southeast/south central Texas than here on the KHOU forum. Outstanding summaries from srainhoutx! Great work, sir.

i agree portastorm and srainhoutx great writeup for even the novice can understand!

[srainhoutx]

Thanks for the kind words, gang. The 12Z Canadian continues to be a bit too fast, but does suggest a stronger storm approaching the NE Mexico/Texas Coast Gulf Coast.

Edit to add: Of cousre the Canadian evetually shoves the energy well E and forms a storm off the SE US Coastline. Just one more reason why that model is not trusted with tropical systems.

[djmike]

I stick to my post several pages back...."Watch this end up being a Mexico storm....AGAIN!" ......hopefully the moisture reaches us this far north!!

[srainhoutx]

The 12Z Euro continues to suggest a very broad area of low pressure with multiple vorticities rotating around that broad low. The Euro is also advertising a wet sloppy system lingering in the Western Gulf.

The attachment 06172012 12Z Euro 12zeurotropical850mbVortSLP168.gif is no longer available

[weatherguy425]

This system could definitely finish off this "abnormally dry" period we've been in, the past couple weeks have certainly helped but still need more up here in Northeast Harris County. ECMWF would be a good scenario for this, as long as it is able to track far enough north. Certainly don't want to get stuck under periphery subsidence.

[srainhoutx]

HPC afternoon updated surface charts suggesting a lingering broad low across the Western Gulf developing next week. The Canadian solution was completely disregarded.

[weatherguy425]

Guess HGX is now leaning towards the ECMWF...

MONSTROUS RIDGING ENVELOPES THE
U.S. PLAINS NEXT WEEKEND THAT WILL NOT ONLY SHUNT/SUPPRESS ANY
TROPICAL ACTIVITY FURTHER SOUTH BUT ALSO SHUT DOWN ANY PRECIPITATION.
AFTER AN ON-AND-OFF AGAIN SHOWERY START TO THE WEEK...IT MAY VERY
WELL END HOT AND DRY (PRECIP-WISE). 31

Hope that ridging will at least back off after this disturbance...

[perk]

Guess HGX is now leaning towards the ECMWF...

MONSTROUS RIDGING ENVELOPES THE
U.S. PLAINS NEXT WEEKEND THAT WILL NOT ONLY SHUNT/SUPPRESS ANY
TROPICAL ACTIVITY FURTHER SOUTH BUT ALSO SHUT DOWN ANY PRECIPITATION.
AFTER AN ON-AND-OFF AGAIN SHOWERY START TO THE WEEK...IT MAY VERY
WELL END HOT AND DRY (PRECIP-WISE). 31

Hope that ridging will at least back off after this disturbance...

Is the HGX being a little premature on this one.

[PA&HOUwx]

Guess HGX is now leaning towards the ECMWF...

MONSTROUS RIDGING ENVELOPES THE
U.S. PLAINS NEXT WEEKEND THAT WILL NOT ONLY SHUNT/SUPPRESS ANY
TROPICAL ACTIVITY FURTHER SOUTH BUT ALSO SHUT DOWN ANY PRECIPITATION.
AFTER AN ON-AND-OFF AGAIN SHOWERY START TO THE WEEK...IT MAY VERY
WELL END HOT AND DRY (PRECIP-WISE). 31

Hope that ridging will at least back off after this disturbance...

Is the HGX being a little premature on this one.

Unfortunately I would say the mid-west ridge as currently modeled has a legit chance of happening. The models have been fairly consistent on developing one in the long range, plus a deep trough set to park itself over the pacific coast will be sure to soar those heights up in the mid-west. End of June and epecially the begining of July will be very warm, unfortunately probably temps near 100F. Lets hope we can get those showers to saturate the ground a little bit, that should help keep temperature from being excessively hot like last summer.

[srainhoutx]

HPC Morning Update:

REGARDING THE TROPICS/LOWER LATITUDE EVOLUTION... THE CANADIAN IS
THE CLEAR OUTLIER IN DEVELOPING A TROPICAL SYSTEM THAT TRACKS
ACROSS SRN FL/WRN ATLC AND BY DAY 7 ENDS UP NOT TOO FAR EWD OF THE
PRIMARY SFC LOW CLUSTERING NEAR NEW ENGLAND. REMAINING CONSENSUS
INDICATES A WAVY SFC FRONT/TROF OVER THE FL PENINSULA WITH SOME
WEAKENING LIKELY BY SAT-MON. MEANWHILE THERE CONTINUE TO BE
INDICATIONS OF PSBL DEVELOPMENT OVER THE SWRN GULF OF MEXICO BUT
ASIDE FROM THE 00Z ECMWF THERE IS CONSIDERABLE RELUCTANCE IN
GUIDANCE TO BRING ANY FEATURE N OF 23-24N LATITUDE. MANUAL FCST
REFLECTS YDAYS NHC/HPC COORDINATION WITH LATEST
GUIDANCE/EXTRAPOLATION USED FOR DAY 7.

[srainhoutx]

The 12Z Canadian has flipped back to a Gulf solution, albeit faster and just SE of New Orleans.

Edit to add: Then stalls it. Somewhat a of a trend back toward a Gulf issue, IMO. We'll see what the Euro offers in an hour or so.