TROPICAL DISTURBANCE INVEST 98L FORECAST SYNOPSIS…JULY 23, 2013…ISSUED 1:25 P.M. EDT…PHFC

DONATIONS NEEDED
Funny dog holds dollars in mouth, isolated white background

JULY 23, 2013…UPDATE…FROM THE 2:00 P.M. EDT TWO…NHC MIAMI:

Graphic is linked to the Outlook.

Forecast based on 10:00 a.m. analysis:

Good day everyone!

Tropical Disturbance INVEST 98L was located  just to the south of the Cape Verde islands as of this morning.  The last information update from ATCF FTP data provide the following information on the disturbance:

Located: 12.2N…22.7W
Motion: W – 15 mph
Max Sustained: 30 mph
Minimum Est. Pressure: 1009 mb / 29.80 in.

The NHC has designated a MEDIUM (40%) chance of the disturbance becoming a tropical cyclone during the next 48 hours.

NHC GRAPHICAL TWO

Analysis of satellite loop imagery indicates convection had decreased overnight, however it appears a slow recovery may be underway.

EUMETSAT IMAGERY

RAMSDIS SATELLITE IMAGE

NAVY ATCF SATELLITE IMAGERY

The current wind shear product from CIMSS indicates an upper level anticyclone becoming established once again, and is pretty much centered over the disturbance at the moment.

EATL WIND SHEAR

Currently, the environment around the disturbance appears to be fairly moist, and SAL is not a factor at this moment.

Upon reading the current TWO form the NHC, I do agree that we should see some further slow development today, and for about the next 24 hours.  Based on the TWO, it is deemed that environmental conditions may become less conducive by tomorrow.  Now, I’ve been pouring over various items, and the only thing I can come up with is…the system temporarily loses the upper level anticyclone, and somewhat cooler SST’s may provide a slowing factor.  However, based on the latest GFS Zonal Shear forecast, INVEST 98L should remain within a light to zero zonal shear environment during the next 72 hours or so, in which soon after, the upper level anticyclone appears to become re-established, all the way up to the northern Leeward Islands at 126 hours out from 06Z this morning.  Based on this shear forecast, I believe INVEST 98L will maintain it’s own, with slow organization over the next 18-24 hours, and remaining Status Quo, until the upper level anticyclone presumably becomes reestablished.

The disturbance is moving toward the W at around 15 mph.  I expect this motion to continue for the next 18-20 hours, before a turn more toward the WNW begins. Based on the current run of the forecast steering layers maps from PSU e-WALL, a WNW motion should persist through about 60 hours in the forecast period, with a nudge back toward the W thereafter.  This is pretty much in agreement with the 12Z Dynamic Model Guidance package, and based on my analysis, I prefer a blend of the TVCN / TVCC / AEMI at the moment, until 98L can become better organized.

INVEST 98L 12Z DYNAMIC MODEL GUIDANCE
12zatcfearlyinvest1best

I will continue to monitor this disturbance for any significant changes to forecast parameters.  Should the disturbance become better organized today, I will post an update sometime this evening.

Elsewhere, Tropical Storm formation is not expected through the next 48 hours.

Have a blessed day!

T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS 
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)
CoCoRaHS OBSERVER

Advertisements

About palmharborforecastcenter

I am a Tropical Forecast meteorologist, providing hurricane forecasts during the Atlantic Hurricane Season. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX, meteorology institute, a four month meteorological internship, and extensive research on numerous meteorological topics such as the MJO, NAO, satellite imagery interpretation, etc. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main client being three different Coast Guard Commands.
This entry was posted in Tropical Synopsis. Bookmark the permalink.

7 Responses to TROPICAL DISTURBANCE INVEST 98L FORECAST SYNOPSIS…JULY 23, 2013…ISSUED 1:25 P.M. EDT…PHFC

  1. dellamom says:

    So, if it follows the track you have mentioned, I am assuming it would be within the realm of possibility (yes, I know all things are possible, no matter how improbable) that it would cross into the Gulf at that point? I know one of them will eventually be the first to get here, but wondering if this one could be it.

    • I don’t think at the moment this is a GOMEX player.

      • dellamom says:

        Sad for the east coast, but happy day for me if it isn’t. I see it is up to 60% now. Thank you for your insight and expertise. My yardstick to measure meteorologists has always been Nash Roberts, a TV weather forecaster in the 50s and 60s who was deadly accurate with his board and marker (pre-electronic doodads) and who managed, despite having to parrot the NHC party line, to subtly convey that he thought Betsy was a threat to N.O. before anyone else noticed. I have every bit as much respect for your thoughts and conclusions as I had for his.

  2. Elliot Lisak says:

    Hi Storm,

    I am going to play meteorologist (like Tex Antoine, if anyone remembers him). The real possibility is that with the colder water, its slowing down, and being in back of the dust, and the temporarily loosing the upper level anticyclonic and the possibility that shear will then ease up. Therefore this gentleman named Dorian might be knocking on the door of Florida?

    Thoughts please?

    Thanks,
    Elliot

  3. Monty says:

    Thanks Storm…looks like we’re going to get our first Cape Verde system.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s