464
FXUS64 KHGX 280914
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
414 AM CDT Tue May 28 2024

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(Today through Wednesday Night)
Issued at 403 AM CDT Tue May 28 2024

While we do have a little bit of a break from the heat, tomorrow
will have the potential to feature more turbulent weather with a
couple rounds of convection expected.

Today will start out with NW flow in the 500mb level with pockets of
PVA moving across the Piney Woods during the late morning to early
afternoon hours. With minimal CIN to overcome, WAA in the lower
levels, and the aforementioned PVA, there may be enough upward
movement to initiate storms across the aforementioned area. The
environment itself will be favorable for some storms to become
strong to severe. CAPE values in that area will be in the 4000 J/kg
range, shear values will be around 40 kts, and lapse rates will be
on the steeper side (~8 C/km). All of these parameters will give
thunderstorms the potential to become more organized with strong
updrafts, resulting in the potential for hail in excess of 1" and
damaging winds in excess of 58 mph.

The next round of storms will set up in a more linear mode out
towards Central Texas, along the dry line and stationary front.
Right now it looks like it will be two different areas of
storms...one across Central Texas/South Texas, and one in the
Panhandle. As these two lines of storms move east, the storms coming
from the Panhandle are expected to drift more SE and congeal with
the storms near San Antonio, resulting in an MCS structure. Ahead of
the MCS, a few discrete thunderstorms may form (again, with the
potential to become strong to severe). The main MCS should reach the
western CWA around or just before midnight tonight, and is expected
to move offshore shortly after sunrise. As the MCS moves through SE
Texas, it has the potential to produce heavy downpours, large hail,
and damaging winds.

The timing of arrival for the MCS is a best guess, and could
certainly arrive a little ahead of schedule or have a slower forward
motion than expected. Hi-res models are not in too much agreement
with the exact timing. The forward motion of the MCS could be
affected by any cold pooling that develops. The strength of the cold
pool could help push it through faster; however, it may result in a
bowing feature that would have the potential to produce stronger
winds.

All that said, SPC has placed the entirety of SE Texas in at least a
Slight Risk (level 2 of 5) for severe weather. Areas along and west
of a line from Weimar to Huntsville to Crockett will be in an
Enhanced Risk (Level 3 of 5) for severe weather.

In addition to the wind and hail threat, there is a Slight Risk for
excessive rainfall for all of SE Texas except for the coastal
portions of counties bordering the Gulf of Mexico. These locations
along with the islands will be in a Marginal Risk. Rainfall totals
will generally be in the 1-2" range north of I-10, with up to an
inch possible further south. Heavier downpours could produce higher
rainfall totals. Right now, 1-hr flash-flood guidance is in the 3-5"
range area wide (we have fortunately been able to recover, for the
most part, from the flooding a couple weeks ago)...after
collaboration with WPC, settled on a Slight Risk for much of the
area in case rainfall rates exceed guidance.

Outside of the active weather, we will still be dealing with heat
and humidity today. Temperatures for today will max out in the 90s
inland and in the upper 80s along the coast. Heat Index values will
be in excess of 100F, but should remain below advisory levels. That
being said, continue to take precautions with the heat and remember
to look before you lock!

Warm and humid nights will continue in the short term with lows in
the 70s area wide. Wednesday we may have a few thunderstorms pop up
in the afternoon; however, they should remain sub-severe. Otherwise,
expect partly to mostly cloudy skies and highs in the 80s. Cloud
cover and lower temperatures should help keep the heat a little more
bearable for Wednesday.

Adams

&&

.LONG TERM...
(Thursday through Monday)
Issued at 403 AM CDT Tue May 28 2024

To summarize the long term in one sentence: Hot, but not as hot,
with a chance of showers and storms every 18 to 36 hours.

The reason for the continued chances of showers and thunderstorms is
due to a series of upper level shortwaves moving through the
Southern Plains. The south to southeasterly flow at the surface will
persist pumping SE Texas with plenty of moisture for these passing
disturbances to tap into (PWATs will be between 1.5 to 2" into next
week). The first of these shortwaves will arrive Thursday morning
into the afternoon. Friday may actually have two disturbances move
through, the first in the morning and then another one late Friday
night. We`ll get a bit of a break during the day on Saturday, but
another weak system will slide through late Saturday night into
Sunday morning. Looks like we get some weak upper level ridging
building as we head into Monday keeping the disturbances to the
north, but meaning we get a bump in the temperatures.

Speaking of temperatures, because of the increased cloud cover and
rain chances the high temperatures Thursday through Saturday will be
fairly close to normal (upper 80s to low 90s). Though the high dew
points thanks to the onshore flow will mean afternoon heat indices
will peak into the 100-105 degree range each day. The increased
cloud cover and onshore flow will mean that overnight lows will be
unseasonably warm with minimum temperatures only down into the mid
to upper 70s for most of the region (and low 80s along the immediate
coast). Temperatures do begin to creep back up Sunday in to Monday
thanks to the building weak ridge, so we could see some high
temperatures nearing the mid 90s on Monday.

Fowler

&&

.AVIATION...
(06Z TAF Issuance)
Issued at 1141 PM CDT Mon May 27 2024

Previous package generally remains on track with winds diminishing
and MVFR cigs beginning to take hold in the latest surface
observations. Widespread MVFR to occasionally IFR cigs will
persist overnight and into the morning, with impacts compounded
by ongoing hazy conditions and the potential for some fog
development. Conditions will improve into the early hours of
tomorrow afternoon as cigs lift and scatter out. A strengthening
SE wind will develop by tomorrow afternoon with sustained speeds
around 10-15 knots and occasional gusts to around 20 knots.
Tomorrow night, a line of thunderstorms is expected to move into
the area from the northwest at approximately 03Z. Some storms
embedded within the line will have the potential to produce strong
to severe wind gusts and potentially some hail.

Cady

&&

.MARINE...
Issued at 403 AM CDT Tue May 28 2024

Light to occasionally moderate onshore flow will persist into next
week with seas around 3 to 5ft. Small craft may need to exercise
caution at times, especially during the overnight periods, due to
occasional wind gusts to near 20kt. The chances for showers and
thunderstorms return Wednesday and persist through the weekend, but
highest coverage of the storms will be inland. The persistent
onshore flow will also lead to a high risk of strong rip currents
through the weekend.

Fowler

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  92  73  87  72 /  20  50  50  20
Houston (IAH)  92  76  86  74 /  10  30  40  20
Galveston (GLS)  87  80  85  77 /  10  30  40  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

$$

SHORT TERM...Adams
LONG TERM....Fowler
AVIATION...Cady
MARINE...Fowler