ATL: INVEST 94L - Discussion

[ozonepete]

Is this "system" more likely to go inland south of Corpus Christi, between Corpus and Galveston, or between Galveston and Sabine Pass?

Models show the low moving south of Corpus Christi, which I don't quite understand. I see the ridge allowing the low to continue it's northward trek, but models disagree as of now.

The Bermuda High ridge is expected to build westward - that's probably why the models turn it westward pretty suddenly. We need to see how quickly heights rise over the northern GOM in the next 24 hours. The less it builds in the more northerly this can get.

[ozonepete]

Here's the 18Z afternoon runs graphic from Colorado State...

[wxman57]

If there is an identifiable surface feature then it may well move ashore south of Texas on Sunday. However, the trof axis should extend well to the north, bringing beneficial rain to much of the TX coast. Development chances are low, and even if it was designated a TD or weak TS there would not likely be any wind issues inland. It's a rainfall event, something Texas needs.

[Tireman4]

If there is an identifiable surface feature then it may well move ashore south of Texas on Sunday. However, the trof axis should extend well to the north, bringing beneficial rain to much of the TX coast. Development chances are low, and even if it was designated a TD or weak TS there would not likely be any wind issues inland. It's a rainfall event, something Texas needs.

As usual, thanks Wxman 57. We appreciate your thoughts...

[tolakram]

Live visible loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=25

[wxman57]

This is just the thing Texas needs - a broad, slow-moving disturbance to bring beneficial rain to the area. Let's hope the rain makes a good bit inland.

[PauleinHouston]

This is just the thing Texas needs - a broad, slow-moving disturbance to bring beneficial rain to the area. Let's hope the rain makes a good bit inland.

Wxman57...as always, your insight is very much appreciated! Based upon what you see, where do you see the "inland" component of rain making it to? The trough lifting will help S/E Texas it appears, but wondering about S/Central and Cen Texas areas?

[TexWx]

This is just the thing Texas needs - a broad, slow-moving disturbance to bring beneficial rain to the area. Let's hope the rain makes a good bit inland.

Definitely a nice set up, if this pans out.

[StormTracker]

Can any pro-met make any sense of this or should I be looking at another chart? Ozone or wxman57, maybe one of you can elaborate on this? Does this show the Bermuda High sliding further west?
http://www.weathercharts.org/noaa-charts.htm#t96-mslp

[KatDaddy]

So true wxman57. We really need significant rainfall well inland.

[vbhoutex]

Won't 94L have the possibility/probability of tapping into the moisture slowly retrograding West towards us from the E GOM? This is the trough(?) that has given the panhandle of FL over a foot of rain in some areas in the last 48 hours.

[southerngale]

Hopefully, this will pan out to bring the much needed rain to many parts of Texas. A rainmaker without the destructive winds is exactly what is needed.

[South Texas Storms]

Unfortunately the models aren't showing much rain making it at least 50 miles inland for some reason. I don't know why. Hopefully they bust.

[djmikey]

Wait. I'm confused. Why are the models wanting to bring this into the Brownsville area? I thought 94L was headed to the upper TX coast. 3 solid days of the talk of TX/LA border.....What just happened?

[ozonepete]

Unfortunately the models aren't showing much rain making it at least 50 miles inland for some reason. I don't know why. Hopefully they bust.

Well it's early yet. They will probably be showing a lot more rain and more of it to the west and north with the next couple of runs.

Personal Forecast Disclaimer:
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.

[southerngale]

:?: Wait. I'm confused. Why are the models wanting to bring this into the Brownsville area? I thought 94L was headed to the upper TX coast. 3 solid days of the talk of TX/LA border.....What just happened?

Nothing happened. We should get rain. See this in the discussion thread.

[South Texas Storms]

Unfortunately the models aren't showing much rain making it at least 50 miles inland for some reason. I don't know why. Hopefully they bust.

Well it's early yet. They will probably be showing a lot more rain and more of it to the west and north with the next couple of runs.

Personal Forecast Disclaimer:
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.

Why do you think that? They have been consistently showing rainfall totals over an inch only along the coast.

[ozonepete]

Can any pro-met make any sense of this or should I be looking at another chart? Ozone or wxman57, maybe one of you can elaborate on this? Does this show the Bermuda High sliding further west?
http://www.weathercharts.org/noaa-charts.htm#t96-mslp

Yeah those charts are fine - I really like them. Only problem is they don't go far west enough. But the 500 mb is the key chart and that does show the ridge building westward. Hopefully it is weak enough on the bottom side that it allows 94L to get north enough to cover most of Texas with rain. You can use these charts from NWS to watch it: http://mag.ncep.noaa.gov/

Choose a model - GFS is fine. I personally don't care for the NAM. Then choose a time 12UTC is the 8AM run and is available around 11:30 AM EDT. The 00UTC run is the 8PM run and available around 11:30PM. choose namer (north America) and the choose 500_rh_ht (Relative Humidity and heights). Choose the loop and then you can watch the 500 mb ridge build westward over the next few days. Watch the moist, high RH air at mid-levels shifting westward. Nice for Texas if it holds!

[ozonepete]

Unfortunately the models aren't showing much rain making it at least 50 miles inland for some reason. I don't know why. Hopefully they bust.

Well it's early yet. They will probably be showing a lot more rain and more of it to the west and north with the next couple of runs.

Personal Forecast Disclaimer:
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.

Why do you think that? They have been consistently showing rainfall totals over an inch only along the coast.

Because the models don't "see" a robust tropical system yet. If this can get up to depression or TS its rain shield will grow quite a bit in size. The models don't usually show those developments until they actually initialize with a developing tropical cyclone. They will often change significantly from 1 run to the next when they go from a disturbance with no surface low to a clearly established TC. As I said, they'll probably expand the moisture, but it's too early yet. And the biggest problem is how far west and how strong that ridge builds in. Too much height rises and the whole system will get pushed too far west and south. It's not at all clear yet. We just have to wait and see. I'm very curious to see what tonight's runs show after 11PM.

[cycloneye]

Stays at 20%


THE INTERACTION BETWEEN A BROAD SURFACE LOW AND AN UPPER-LEVEL
TROUGH IS PRODUCING SHOWERS AND THUNDERSTORMS OVER MUCH OF THE
WESTERN GULF OF MEXICO. THE LOW IS EXPECTED TO MOVE NORTHWARD OR
NORTH-NORTHWESTWARD AT 5 TO 10 MPH OVER THE NEXT COUPLE OF DAYS
TOWARD THE NORTHEASTERN MEXICO AND TEXAS COASTS. UPPER-LEVEL WINDS
ARE NOT CONDUCIVE FOR SIGNIFICANT DEVELOPMENT. THIS SYSTEM HAS A
LOW CHANCE...20 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS. REGARDLESS OF DEVELOPMENT...THIS DISTURBANCE WILL
LIKELY PRODUCE PERIODS OF LOCALLY HEAVY RAINFALL AND GUSTY WINDS
ACROSS PORTIONS OF UPPER TEXAS AND SOUTHWESTERN LOUISIANA BY LATE
SATURDAY NIGHT AND CONTINUING INTO SUNDAY.