646
FXUS64 KHGX 221133
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
633 AM CDT Tue Apr 22 2025

...New AVIATION...

.SYNOPSIS...
Issued at 336 AM CDT Tue Apr 22 2025

Very early in the week our weather has been active, and this
largely looks to continue through the week. On the bright side,
there does not appear to be any day that looks obviously worse
than any other. On the downside, it`s the time of year where even
without an organized severe weather or heavy rain threat, a
localized problem could emerge in the strongest storm or two of
the day. Some of the key things to remember for the rest of the
week:
- Each day for the rest of the work week will feature potential
  for showers and storms in parts of the area. While Wednesday
  appears to have the best potential area-wide, any given spot
  could see storms on any given day.
- There does not appear to be an organized severe weather threat.
  However, there is plenty of available moisture, so a localized
  flooding threat could emerge if a particularly strong storm
  occurs over a particularly vulnerable spot. Those that saw heavy
  rain yesterday are definitely vulnerable spots, as well as the
  usual low-lying and/or poor drainage spots.
- Similarly, there is no apparent organized threat for severe
  storms. However, an individual storm or two each day could be
  capable of producing an isolated strong to borderline severe
  gust.

&&

.SHORT TERM...
(Today through Wednesday Night)
Issued at 336 AM CDT Tue Apr 22 2025

After a very rainy day yesterday, we`re seeing some of that
moisture return back to the atmosphere...but only just barely...as
fog has cropped up along the coast and up the Trinity Valley, and
is now beginning to expand further. While there have been a few
dense spots so far, nothing has - yet - prompted a need for a
dense fog advisory. However, should those dense spots begin to
become more numerous and widespread, that could be on the table.

All in all, for an area that is very used to having stretches of
active weather, but in a scattered, disorganized way, today and
tomorrow (and really the rest of the week, but you can read more
on that below) should feel pretty familiar. We find ourselves in
roughly southwestish flow aloft, giving us an upper atmosphere
connection to Pacific moisture. While down closer to the surface,
low level ridging to the east makes our flow a little more
southerly/southeasterly, with a solid Gulf connection. The result
will be precipitable water values near or just over the 90th
percentile. Pair that with numerous, albeit modest, vort blobs
passing overhead and CAPE values around 2000 J/Kg, give or take
bit, and all we`ll need to get some scattered initiation is to
lose the cap, which we should do pretty easily today.

So, what are the main consequences of this? Well...thankfully
probably not too much for the large majority of us. These
vorticity blobs are not vigorous, indeed they`re pretty subtle.
Shear is fairly solid, above 20 knots, but also not exceptionally
big. Similarly, PWATs around 1.25 inches is plenty moist (again,
around the 90th percentile) so we can get some stout, rainy,
loosely organized cells. But also things don`t stand out as
particularly scary, either. Still, it`s that time of year with
decent amounts of shear, lift, instability, and moisture, so we`ve
still got to keep our eyes open each day for the strongest storms
of the day to maybe drop a problematic amount of rain, or an
isolated strong gust of wind.

Another thing we need to watch out for, as featured in the 00Z
HRRR! A severe threat *does* exist out in West Texas, and while
this isn`t exactly our usual late-spring, northwest flow regime
where rogue MCSs come at us from North Texas, we do find ourselves
in an environment that may not be able to birth an organized
convective system, but could certainly prolong an existing
complex`s lifespan enough to push some strong storms in from the
west early tomorrow morning. These events are, of course,
notoriously poorly handled by the models, so I don`t want to get
too out over my skis on it, but it may be something else to keep a
watch for on my next shift.

&&

.LONG TERM...
(Thursday through next Monday)
Issued at 1212 AM CDT Tue Apr 22 2025

The synoptic flow aloft remains southwesterly, so following
Wednesday`s embedded shortwave trough we receive yet another one on
Thursday going into Friday. More favorable lifting mechanisms
(closer to the shortwave and upper level diffluence) will be across
the Brazos Valley/Piney Woods, so expect rain chances to be higher
in these locations compared to closer to the coast. Persistent
onshore flow will help keep PW values near or above the 90th
percentile (~1.60"), so we could see some locally heavy downpours at
times in any of the stronger showers/storms. Going into the weekend,
ridging aloft looks to build in leading to a decrease in rain
chances and an increase in temperatures.

Speaking of temperatures, we start out at the end of the work week
with high temperatures in the low to mid 80s and low temperatures in
the upper 60s to low 70s. With ridging aloft building in going into
the weekend, we begin to see an upward trend in temperatures that
takes us into the upper 80s to low 90s for highs and the low to mid
70s for lows by the latter half of the weekend. Based on some of the
ensemble guidance and long-range NBM guidance...temperatures may
remain in that range well into next week.

Batiste

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 633 AM CDT Tue Apr 22 2025

Wildly annoying conditions at outset, with bouncing between LIFR
VSBY/CIGs and VFR. Plus, some isolated stops at MVFR CIGs for fun.
This should persist for next few hours, but gradually give way to
MVFR CIGs more broadly, then rising to VFR in the afternoon while
SE winds persist. Have some PROB30s in for scattered SHRA/TSRA.
This could occur area-wide, but focusing on the UTS-SGR band for
best chances. Bring back nocturnal CIGs late - go only with MVFR
for now, but some guidance suggests IFR on the table.

Low probability outcome for impacts to SE Texas, but will have to
watch development of thunderstorm complex in West Texas as it
traverses the state tonight. Some models do bring SHRA/TSRA to
area in 09-13Z window. Not a big enough threat to explicitly put
in TAFs, but worth a mention here.

&&

.MARINE...
Issued at 1212 AM CDT Tue Apr 22 2025

Light to occasionally moderate southeasterly winds will persist
throughout the week. Around and after midweek, an extended
southeasterly fetch develops across the Gulf leading to an increase
in wave heights potentially reaching caution flag criteria. The rip
current risk looks to remain elevated throughout the week as well.
Chances for showers and thunderstorms will persist throughout most
of the week as Gulf moisture interacts with various upper level
disturbances.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  88  69  82  69 /  20  30  60  20
Houston (IAH)  84  70  82  70 /  30  30  50  20
Galveston (GLS)  80  73  81  73 /  30  30  40  10

&&

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

$$

SHORT TERM...Luchs
LONG TERM....Batiste
AVIATION...Luchs
MARINE...Batiste