August 2019: Weak Cold Front/Rain Chances To End August

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tireman4
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Re: August 2019: Heat Returns/Tracking The Tropics

Post by tireman4 » Tue Aug 27, 2019 1:03 pm

252
FXUS64 KHGX 271803
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
103 PM CDT Tue Aug 27 2019

.AVIATION...
VFR FEW-BKN decks across the board through the early Wednesday
morning hours. Isolated showers beginning to pop up in the
afternoon heat so anticipate the occasional VCSH. Tempo MVFR
ceilings around sunrise once again. A weak boundary washing out
across the region tomorrow may provide the focus for a higher
areal coverage of Wednesday -TSRA once lower 90 surface
temperatures are achieved. This scenario will create a light and
variable wind field. 31

&&

.PREV DISCUSSION... /ISSUED 1053 AM CDT Tue Aug 27 2019/

DISCUSSION...
850 MB temperatures have cooled slightly from yesterday but
considering the warm start to the day, afternoon temperatures look
to be similar to yesterday. A cumulus field is developing
areawide with some cirrus moving over the top, so cloud cover
might be a bit more prevalent than yesterday. Water vapor imagery
shows a weak upper level low spinning just off the coast.
Temperatures are off to a warm start so will leave the Heat
Advisory as configured with the higher heat index values expected
near the coast.

Two areas of concern with regard to precipitation this afternoon.
The first area of concern is over the north as a weak outflow
boundary trudges into the area. Not sure there will be much in the
way of activity but it certainly bears watch. The second area of
concern will be over Harris, Ft Bend and Galveston counties closer
to the periphery of the upper low over the western Gulf. HiRes
guidance is bullish with PoPs between 21-00z and this is also an
area with strong mid level forcing by both the NAM12 and GFS. Will
be watching this area closely as well. Some capping is noted in
the 85-70 MB layer and temperatures will need to reach 94-95
degrees to initiate convection. Too much uncertainty to go much
higher than 20 PoPs for now. 43

&&

Cromagnum
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Re: August 2019: Heat Returns/Tracking The Tropics

Post by Cromagnum » Tue Aug 27, 2019 1:19 pm

I don't get it. Yesterday was a 50% chance of rain at my house and it didn't do anything. Today was basically 0 % chance and it's pouring.

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by DoctorMu » Tue Aug 27, 2019 2:11 pm

jasons wrote:
Tue Aug 27, 2019 9:18 am
djmike wrote:
Tue Aug 27, 2019 4:42 am
Question: is Florida wide enough to tear apart any system or is their a chance it could reform in the Ngulf?
That’s not an easy question to answer. It depends on a number of factors, such as - what part of the peninsula will the storm cross? The most southern portion across the Everglades, which is mostly water anyway, or further up, where the Florida Ridge actually has some hills?

Storm motion - obviously the quicker it moves, the less influence the land will have.

Atmospheric environment - might be the biggest factor - is the storm strengthening or weakening as it approaches? Is it a large moist pocket with good outflow channels, or is the atmosphere just marginal?

In short - it depends and every storm is unique. Some storms collapse when they touch land and some storms actually continue to intensify with the ‘brown ocean’ effect and/or great atmospheric conditions.

There is no black or white answer...you just have to closely monitor...

"The Florida Alps?" between Lake City and I-4? They might be 200-300 ft high in altitude. "Sugarloaf Mountain" is 312 ft above sea level and NE of Orlando - that's the highest pt in the state. Plus, the state is potholed with lakes - Florida is like a giant, porous reef. The panhandle is probably hillier than the peninsula. A storm could easily reform on the other side in the GoM. Friction is modest on an E-W track.

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by jasons2k » Tue Aug 27, 2019 2:14 pm

Cromagnum wrote:
Tue Aug 27, 2019 1:19 pm
I don't get it. Yesterday was a 50% chance of rain at my house and it didn't do anything. Today was basically 0 % chance and it's pouring.
It also seems like the day shift is more optimistic/generous with rain chances than the overnight shift.

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by jasons2k » Tue Aug 27, 2019 2:21 pm

DoctorMu wrote:
Tue Aug 27, 2019 2:11 pm
jasons wrote:
Tue Aug 27, 2019 9:18 am
djmike wrote:
Tue Aug 27, 2019 4:42 am
Question: is Florida wide enough to tear apart any system or is their a chance it could reform in the Ngulf?
That’s not an easy question to answer. It depends on a number of factors, such as - what part of the peninsula will the storm cross? The most southern portion across the Everglades, which is mostly water anyway, or further up, where the Florida Ridge actually has some hills?

Storm motion - obviously the quicker it moves, the less influence the land will have.

Atmospheric environment - might be the biggest factor - is the storm strengthening or weakening as it approaches? Is it a large moist pocket with good outflow channels, or is the atmosphere just marginal?

In short - it depends and every storm is unique. Some storms collapse when they touch land and some storms actually continue to intensify with the ‘brown ocean’ effect and/or great atmospheric conditions.

There is no black or white answer...you just have to closely monitor...

"The Florida Alps?" between Lake City and I-4? They might be 200-300 ft high in altitude. "Sugarloaf Mountain" is 312 ft above sea level and NE of Orlando - that's the highest pt in the state. Plus, the state is potholed with lakes - Florida is like a giant, porous reef. The panhandle is probably hillier than the peninsula. A storm could easily reform on the other side in the GoM. Friction is modest on an E-W track.
It is modest relative to other places, like “Shredderola” especially, but It’s enough to make a difference. For example, a trek from Miami to Naples would weaken less than a trek from Vero Beach to Clearwater, all else being equal.

I am a Florida native ;-)

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by tireman4 » Tue Aug 27, 2019 3:10 pm

233
FXUS64 KHGX 272045
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
345 PM CDT Tue Aug 27 2019

.NEAR Term...Showers and thunderstorms developed earlier this
afternoon and will likely persist through 00z before quickly
ending with the loss of heating. Rain cooled air/outflows have
allowed temperatures to fall and heat index values are below 105
degrees. In areas away from the rain, sfc dew points have mixed
out and these areas are also below Advisory criteria. Have trimmed
the Heat Advisory back and will only include the immediate coast
and portions of the SW zones in the Advisory. Will end the Heat
Advisory at 7 PM. HiRes guidance did well today but models still
had some trouble getting the location correct. Have broad brushed
chance PoPs over the central zones. 43

.SHORT TERM...
Further north, an outflow boundary over East Texas will sag into
the NE zones and will serve as a focus for shra/tsra tonight and
will carry lowish PoPs in that area tonight. A weak cold front
will move into the area on Wednesday afternoon. Lower 500 mb
heights, slightly cooler 850 temperatures and scattered showers
should allow high temperatures to be a few degrees cooler and a
Heat Advisory is not expected to be needed. The highest heat index
values currently forecast on Wednesday range between 101 and 106
degrees. The weak front will probably sag into the central zones
before stalling but the front in combination with a weakness aloft
will allow the chance for showers and thunderstorms to persist
Wednesday night into Thursday. High temperatures on Wed/Thu will
be strongly dependent on cloud cover and when/if showers develop.

43

&&

.LONG TERM...
The front will hang around Thursday night into early Friday but
the boundary will become less defined. 500 heights remain low and
PW values remain around 2.00 inches so still expecting daytime
heating to trigger showers and storms. Labor Day weekend is
looking a bit better with a drying trend Sat/Sun. An inverted
upper trough will approach from the east Sunday night into Monday
and moisture levels increase once again. Could get some showers as
early as Sunday night but more likely on Mon/Tues as the upper
trough approaches the TX coast. 43

&&

..MARINE...
High pressure over the northern Gulf will maintain tranquil maritime
conditions throughout the remainder of the week. Slight to low end
chances for a passing shower or vicinity thunderstorm. Tomorrow`s
weak northern inland boundary working its way into northeastern
Texas will position backing high pressure over the eastern United
States. The orientation of this high will create a few days of
either light southerly or variable breezes over near 2 foot average
sea heights. A Labor Day weekend easterly fetch will push in a
higher swell and pick up seas by an average foot. 31

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 77 96 77 97 76 / 20 30 30 30 10
Houston (IAH) 79 96 79 95 78 / 30 50 30 40 20
Galveston (GLS) 83 92 84 92 82 / 20 30 20 30 30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Heat Advisory until 7 PM CDT this evening for the following
zones: Brazoria Islands...Coastal Brazoria...Coastal
Jackson...Coastal Matagorda...Galveston Island and Bolivar
Peninsula...Inland Jackson...Inland Matagorda...Matagorda
Islands.

High Rip Current Risk until midnight CDT tonight for the
following zones: Galveston Island and Bolivar Peninsula.

GM...NONE.
&&

$$

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by jasons2k » Tue Aug 27, 2019 3:12 pm

Dang outflow/sea breeze has a void of no convection from I-10 near Katy arcing over past 290, 45, then past 59, to about the Liberty County line and then the rain resumes.

I sure hope this changes!!

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by javakah » Tue Aug 27, 2019 3:14 pm

Ahhhh, finally getting a few minutes of soaking rain here in Fulshear. It's been ages since we had more than a few drops. Any approaching storm just kept falling apart right before getting here in the past weeks, so we'd only get a couple of drops.

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by jasons2k » Tue Aug 27, 2019 3:52 pm

The outflow has pushed through here now. No cumulus or towering cumulus to my south, either. One of the worst weather months ever!!

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Re: August 2019: Heat Returns/Tracking The Tropics

Post by Kingwood36 » Tue Aug 27, 2019 3:54 pm

Anyone noticing that hook now to to west for Dorian? Once it crosses Florida...may enter the gulf

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