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an update from Eric Berger on Space City Weather, Matt should have another by 7 PM tonight

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Tornado Warning near Port Aransas, TX

We haven’t seen too much rain here in central Wharton County yet but just a few miles to my south they’ve already seen up to 10” in spots.

Mesoscale Discussion 0634
NWS Storm Prediction Center Norman OK
1215 PM CDT Sun May 16 2021

Areas affected...Central/East TX

Concerning...Severe potential...Watch unlikely

Valid 161715Z - 161915Z

Probability of Watch Issuance...20 percent

SUMMARY...A few strong to severe storms possible this afternoon
across portions of central and east TX. Isolated damaging wind gusts
are the primary threat.

DISCUSSION...Regional satellite and radar imagery reveals a pair of
MCVs across the southern Plains, one over central OK and the other
along the middle TX Coast. Modest southerly low-level flow exists
between these two features, roughly along and east of I-35. The
thermodynamic environment is expected to remain only marginally
buoyant, with overall buoyancy tempered by the limited diurnal
heating. Even so, thunderstorms are expected to persist while
gradually drifting eastward throughout the day.

Surface winds have been backing a bit more southeasterly just ahead
of the storms, which, when coupled with the modest low-level
southerly flow and westerly flow aloft, result in a kinematic
profile that could support a supercell or two. Damaging wind gusts
would be the primary threat with any stronger updrafts/supercells,
with some low-probability potential for a brief tornado as well.
Marginal and isolated nature of the severe threat is expected to
preclude the need for a watch.

https://twitter.com/NWSWGRFC/status/1393933944245084163

New WPC qpf map.

It will go west and north of us as usual....

Area Forecast Discussion
National Weather Service Houston/Galveston TX
319 PM CDT Sun May 16 2021

.SHORT TERM...[Through Monday Night]

Areas south of I-10 got pummeled today with periods of heavy rain.
The hardest hit areas were in Jackson, southern Wharton and
Matagorda counties where as much as 12 to 14 inches of rain fell.
A Flash Flood Watch previously in effect will be allowed to expire
at 4 PM. Model performance so far today has been poor but the HRW
WRF-NSSL initialized well and seems to be being do the best out of
the models. Have leaned strongly toward this model for the next 36
hours.

So what`s going to happen? Not 100 percent sure, but current
thinking is the large convective burst in Matagorda county will
weaken into a stratiform rain shield as it moves up the coast
eventually fizzling out after 00z. For the most part, feel there
will be a significant gap in the rainfall overnight as the short
wave responsible for today`s precip moves east and the strong
splitting jet structure becomes briefly zonal. PW values also
briefly dip from 2.00 inches down to around 1.60 inches. All of
this points to a decreasing trend in PoPs and QPF. Min T values
tonight should remain warm with clouds and winds failing to
decouple.

Toward sunrise Monday, upper level winds begin to split again as
another short wave moves toward SE TX. The WRF-NSSL does not
generate much precip toward morning and this is concerning because
the last 4 runs of the HRRR shows convection re-firing on what
looks like a residual outflow boundary from today`s convection.
Although confidence is not terribly high, feel likely PoPs are
warranted over the east by 12z Monday and PoPs will increase
across the rest of the CWA as moisture levels deepen and favorable
jet dynamics stay in place. Will again mention locally heavy for
Monday as the potential exists for pockets of heavy rain. Will
another Flash Flood Watch be needed? Maybe? But the area most
likely to receive heavy rain on Monday did not have heavy rain
today so will hold off on issuing a Watch for Monday and defer to
the midnight shift. Clouds and rain will again keep MaxT values
on the cool side with highs near 80. Clouds will hang in Monday
night so not expecting much of a drop off in temperatures with
MinT values in the upper 60`s north to low/mid 70`s south. 43

&&

.LONG TERM [Tuesday Through Sunday]...

By Tuesday morning, the slowly migrating cutoff low will be centered
somewhere near the Oklahoma/Texas Panhandle, which will strengthen
our onshore flow across Southeast Texas. This will drive up more
Gulf moisture across our area with PWATs climbing to approximately
1.75 inches. Models hint at PVA lobes pushing through, which will
help kick up showers and thunderstorms throughout the day. Highest
rain chances and rainfall amounts will be in our NW counties, with
rainfall totals predicted to be 1-2" and up to 1" everywhere else.

Wednesday and Thursday are still shaping up to be another day with
heavy rainfall amounts despite global models differing in mesoscale
features overhead. As global models show the cutoff low dissipating
and/or drifting north, a low-level jet overhead of us will
strengthen, driving PWATs up even further to approximately 2 inches,
priming the atmosphere with ample moisture. A deep wedge of moisture
and rain across our CWA will stretch across the Central Plains
combined with more PVA invigorating convection. As if that weren`t
enough, the GFS and ECMWF hint at a surface low developing across
South TX near Brownsville and pushing north. All of these
ingredients will lead to a nearly stationary boundary of heavy
rainfall across the I-45 corridor with rainfall totals expected to
reach approximately 6-9 inches Wednesday through Thursday.

Unfortunately, rainfall is expected to persist through the rest of
the long-term period. A high pressure over the Southeast US tries to
build into our area, which might suppress convection slightly, but
models still hint at rainy weather persisting through the weekend.

KBL

Texaspirate11 wrote: ↑Sun May 16, 2021 3:56 pm It will go west and north of us as usual....

I think a lot will depend on what comes of the potential low near Brownsville.

I’m right at 1” IMBY today. Perfect type of rain for the lawn, trees and my garden that is already producing green beans, peppers, cucumbers, squash and pumpkins starting to fruit as well. Will see what comes of the potatoes, carrots, and watermelon.

Def don’t want 10” but I’d rather have that at this point than no rain for the next several months.

Louise, TX area has already seen close to a foot of rain today. I just missed it today by about 15-20 miles.

We drove through Ganado around noon today and water was everywhere. Hwy 59N by Louise had high water in one lane. The rain was incredible. We were driving north on Hwy 172 from Port Alto and the closer to Ganado, the harder the rain. The fields were flooded. The good thing was that everyone was driving with respect and caution.

Only .25" IMBY here in Cypress so far today. I'll take what we can get.

Cpv17 wrote: ↑Sun May 16, 2021 4:33 pm Louise, TX area has already seen close to a foot of rain today. I just missed it today by about 15-20 miles.

See that's what makes me really concerned about this week, if we are already seeing those kind of totals with a much weaker disturbance and less lift than what we will see later this week.That makes me think global models may be under doing the rainfall potential, and we'll have to rely daily on the short range mesoscale models to determine which areas have the potential for excessive rainfall.

don wrote: ↑Sun May 16, 2021 5:35 pm

Cpv17 wrote: ↑Sun May 16, 2021 4:33 pm Louise, TX area has already seen close to a foot of rain today. I just missed it today by about 15-20 miles.

See that's what makes me really concerned about this week, if we are already seeing those kind of totals with a much weaker disturbance and less lift than what we will see later this week.That makes me think global models may be under doing the rainfall potential, and we'll have to rely daily on the short range mesoscale models to determine which areas have the potential for excessive rainfall.

I’ve heard reports coming out of that area just south and sw of El Campo of as much as 14” from this morning. I picked up 1.50” today. Nice steady rain for most of the day.

Im becoming increasingly more concerned that the global models are underdoing the potential rainfall accumulations for tuesday night-thursday,

Solid, steady rain in Friendswood all day today.

I’m getting a bit worried about the next two days as well.

Yeah none of the models were predicting 14 inches of rain today in EE Texas but yet it happened. Im thinking its in the realm of possibility that someone somewhere in SE Texas Tuesday-Thursday could see a bullseye of 15-20 inches. Just depends on where the heavy rain sets up and trains. Looking ar a solid 48-60 hour window of very rain

Only an inch of rain at my place based on rain gauge, but standing water everywhere. Nice rainbow action to cap off the day. Even got a double rainbow.

Jeff on FB tonight.

13.5 inches of rain today near Ganado TX in Jackson County

This airmass and pattern setup mean business, flood threat increases this week.

Be prepared

Impressive lightning storm off to the southeast of Galveston.