MARCH 2018 - Pleasant Good Friday/Easter Weekend Ahead

[Cromagnum]

Full sun south of Houston for a lot of the morning. Winds from the south have kicked up a couple notches. Gonna be interesting this afternoon around here.

[ticka1]

Not so much worried about the flooding but severe weather. Has that potential lessen any for Houston Metro/SE Texas area?

[srainhoutx]

Severe Thunderstorm Watch likely coming in the next hour or two...

03282018 mcd0187.gif

Mesoscale Discussion 0187
NWS Storm Prediction Center Norman OK
1138 AM CDT Wed Mar 28 2018

Areas affected...southeast TX through central and northern LA

Concerning...Severe potential...Watch likely

Valid 281638Z - 281745Z

Probability of Watch Issuance...80 percent

SUMMARY...Storms are expected to increase into the afternoon with a
threat for damaging wind, a couple of tornadoes and perhaps some
hail. A WW will probably be needed soon.

DISCUSSION...Late this morning storms have increased in organization
along a quasi-stationary rain reinforced boundary over southeast TX.
A weak meso-low was evident and may continue northeast along the
boundary. Moreover, partial cloud breaks within the moist boundary
layer will contribute to further destabilization with 1500 J/kg
MLCAPE likely. An increase in the low-level jet is expected during
the afternoon which will eventually result in favorable 0-2 km
hodographs for low-level mesocyclones and some tornado threat in
addition to damaging wind as storms continue northeast into the
afternoon.

..Dial/Edwards.. 03/28/2018

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...JAN...LCH...SHV...HGX...EWX...

[srainhoutx]

Excellent Update from HGX Forecaster Luchs...

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1138 AM CDT Wed Mar 28 2018

.UPDATE...

Little change in the big picture for the weather today, as there
will still be potential for strong to severe thunderstorms as well
as locally heavy rain. Forecast update retrends temperatures for
the influence of rain and cloud cover, and also attempts to refine
PoPs and QPF to the extent that it can be at this time.

Key Points:
- Locally heavy rain is still expected both where it is currently
raining this morning, as well as towards the coast as the focus
for rain drifts towards the coast into tonight. Widespread
amounts of 1-3 inches are expected, with localized maximums of
4-6 inches possible.
- Severe weather will be the highest threat to the southeast of
where it is currently raining. Winds and clouds are creating a
boundary that may become the focus for later storms. The
strongest storms will have a threat for both severe hail
(perhaps up to around ping-pong ball size) and damaging wind
gusts. Tornadoes will also be possible and cannot be ruled out.

The Scene:

A band of showers and storms are in place, oriented from southwest
to northeast from roughly Columbus through Huntsville and up into
Trinity County. Rainfall reports in the past three hours range
from just under an inch to 2.3 inches. Satellite also shows good
moist inflow, particularly for the currently warned storm near
Huntsville as it has remained attached to a moisture convergence
axis that extends to the Gulf.

Southeast of these storms, sun has largely broken out across much
of the area, with temperatures responding. Angleton is up to 80
degrees, Sugar Land and Palacios to 78, and Bay City to 79.
Additionally, this area shows southerly winds up to 20 or so
knows, with gusts in the 20s up to 30 knots. The sun and windflow
will surely only sharpen up the gradient along the outflow
boundary, and does appear to be largely holding it in place in a
region of precipitable water that SPC Mesoanalysis shows at 1.7 to
1.8 inches. This has helped prompt the extension of a moderate
risk for flash flooding across much of the area by WPC.

This boundary also looks likely to provide a focus for the next
round of storms, and the higher threat of severe weather. We have
a southerly low level jet of 35ish knots feeding into our
boundary, and with the sun breaking through, MLCAPE is already
pushing above 1000 j/kg and reaching 1500 in the warmer spots
seems reasonable. Lapse rates below 700 mb are a little lame now,
but expect that warming should be able to overcome much of this
and allow us to tap into better instability above that. SHIP
analogs at IAH do nudge into the 25th percentile for 2.5 inch
hail, but given the relatively high freezing and wet bulb zero
heights, that may be a bit aggressive. Regardless, there should be
some potential for severe hail in the strongest storms.

Wind damage is a clear threat as we already have reports of trees
down with the storm near Huntsville. DCAPE values aren't terribly
impressive in the mesoanalysis, but HRRR soundings suggest that we
could get marginal values for severe winds.

Finally, the environment does appear to be supportive of some
tornado threat. Effective SRH is quite high near and coastward of
the current storms, with the bulk of that packed into the lowest
km. Hodographs both from a recent UH sounding and HRRR soundings
suggest this will continue, with good curvature in the lowest
levels, but less impressive above that. 1 km shear is also quite
strong, though how effectively storms may tap into that shear may
strongly depend on their orientation and movement relative to the
boundary. This may limit the number and intensity of the tornado
threat, but don't expect it to eliminate it.

[srainhoutx]

Tornado Watch issued until 9:00 PM CDT

[tireman4]

And a Public Service Announcement....

[sau27]

Based on the last few HRRR runs I wouldn't be surprised to see 1 or 2 discrete supercells develop SW of town and slide NE ahead of the boundary.

Much will depend on where the frontal/outflow boundary ends up when the disturbance from the SW arrives. That boundary will act like a railroad track once it does.

[tireman4]

Strong Storm Near College Station....

[Ounce]

Looking at the wind direction on MyRadar app, it looks like a Low might be forming east of Cotulla or is that just the end of the front or some divergence thing?

[ticka1]

Stay weather aware.

[srainhoutx]

Looking at the wind direction on MyRadar app, it looks like a Low might be forming east of Cotulla or is that just the end of the front or some divergence thing?

Latest surface analysis as of 1620Z from the WPC suggests a surface low is just WNW of San Antonio with a trough axis out ahead of the frontal boundary roughly from San Antonio to Brenham/Huntsville and Lake Livingston. Another surface low is just N of Monterrey in Mexico with yet another trough axis extending to the tail end of the front along the Rio Grande River. I am a bit concerned about the rather abundant sunshine down near Victoria on E into our SW Zones. I also see some indications of possible gravity waves attempting to develop W and S of Corpus Christi. Gravity waves can sometimes be precursors of supercell development in the next several hours.

[srainhoutx]

NWS Houston‏Verified account @NWSHouston · 1m1 minute ago
12:44 PM CDT Radar Update: a second line of strong thunderstorms is beginning to move into the northern parts of our area. Additionally, a line of thunderstorms is beginning to develop over Fort Bend and Harris Counties. #bcswx #houwx #glswx #txwx

[sau27]

Looking at the wind direction on MyRadar app, it looks like a Low might be forming east of Cotulla or is that just the end of the front or some divergence thing?

Latest surface analysis as of 1620Z from the WPC suggests a surface low is just WNW of San Antonio with a trough axis out ahead of the frontal boundary roughly from San Antonio to Brenham/Huntsville and Lake Livingston. Another surface low is just N of Monterrey in Mexico with yet another trough axis extending to the tail end of the front along the Rio Grande River. I am a bit concerned about the rather abundant sunshine down near Victoria on E into our SW Zones. I also see some indications of possible gravity waves attempting to develop W and S of Corpus Christi. Gravity waves can sometimes be precursors of supercell development in the next several hours.

Going for the lift bingo today: Outflow boundary, front, shortwave, gravity waves

[DoctorMu]

NWS Houston‏Verified account @NWSHouston · 1m1 minute ago
12:44 PM CDT Radar Update: a second line of strong thunderstorms is beginning to move into the northern parts of our area. Additionally, a line of thunderstorms is beginning to develop over Fort Bend and Harris Counties. #bcswx #houwx #glswx #txwx

Really nasty cell with wind, lightning, heavy rain in CLL.



sliding down to Navasota.

[Ounce]

Looking at the wind direction on MyRadar app, it looks like a Low might be forming east of Cotulla or is that just the end of the front or some divergence thing?

Latest surface analysis as of 1620Z from the WPC suggests a surface low is just WNW of San Antonio with a trough axis out ahead of the frontal boundary roughly from San Antonio to Brenham/Huntsville and Lake Livingston. Another surface low is just N of Monterrey in Mexico with yet another trough axis extending to the tail end of the front along the Rio Grande River. I am a bit concerned about the rather abundant sunshine down near Victoria on E into our SW Zones. I also see some indications of possible gravity waves attempting to develop W and S of Corpus Christi. Gravity waves can sometimes be precursors of supercell development in the next several hours.

Going for the lift bingo today: Outflow boundary, front, shortwave, gravity waves

Sure looks like a plethora of outflow boundaries for today.

[srainhoutx]

There you go DoctorMu...

Special Weather Statement
National Weather Service Houston/Galveston TX
120 PM CDT WED MAR 28 2018

TXZ195>198-281845-
Washington TX-Brazos TX-Grimes TX-Burleson TX-
120 PM CDT WED MAR 28 2018

...SPECIAL WEATHER STATEMENT...

At 120 PM CDT, Doppler radar was tracking a strong thunderstorm near
Snook, or 8 miles southwest of College Station, moving northeast at
40 mph.

Winds in excess of 30 mph will be possible with this storm.

Locations impacted include...
College Station, Bryan, Caldwell, Snook, Millican, Kyle Field and
Wellborn.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

A Tornado Watch remains in effect until 900 PM CDT for southeastern
Texas.

[tireman4]

Weather Update...

[srainhoutx]

Flood Advisory coming shortly for our Northern Counties

Flood Advisory
National Weather Service Houston/Galveston TX
132 PM CDT WED MAR 28 2018

Burleson TX-Grimes TX-Washington TX-Brazos TX-Madison TX-Walker TX-
132 PM CDT WED MAR 28 2018

The National Weather Service in League City has issued a

* Flood Advisory for...
Burleson County in southeastern Texas...
Northwestern Grimes County in southeastern Texas...
Western Washington County in southeastern Texas...
Brazos County in southeastern Texas...
Madison County in southeastern Texas...
Northwestern Walker County in southeastern Texas...

* Until 430 PM CDT.

* At 130 PM CDT, Doppler radar indicated heavy rain due to training
thunderstorms. These will cause minor flooding in the advisory
area. Up to two to locally three inches of rain have already
fallen within the advisory area. Thunderstorms moving in from the
southwest may put down another two to four inches of rain within
the next couple of hours.

* Some locations that will experience flooding include...
College Station, Bryan, Madisonville, Caldwell, Somerville, Snook,
Bedias, Kurten, Burton, Wixon Valley, Lake Somerville Dam, Kyle
Field, Normangee, Iola, Lyons, Deanville, Quarry, Chriesman, North
Zulch and Wellborn.

[mckinne63]

We are heading to Louisiana from Stafford, TX this afternoon about 3pm. Will we be in front of the storms?

[srainhoutx]

We are heading to Louisiana from Stafford, TX this afternoon about 3pm. Will we be in front of the storms?

If you can leave earlier...I would. Storms are developing quickly across Fort Bend and Western Harris Counties. We expected storms to begin firing around 1:00 PM CDT and it appears they are right on que... Getting ahead of that I-10 mess eastbound as early as possible would my advise.