October: Chilly Halloween Outlook

[Cromagnum]

Good cells on the south side

[Texaspirate11]

Nice rain at the bay this morning.

[Cpv17]

I’m not real sure why rain chances are so high today. I don’t see anything on the models that warrants such high chances.

[srainhoutx]

Monday morning weather briefing from Jeff:

Cool and dry air mass of Saturday is quickly being replaced by incoming warm and humid Gulf air mass.

Warm front near the coast this morning will lift northward today. Thus far deep convection has been focusing along the 850mb front generally from Huntsville to Lake Livingston and then also along the coast from Galveston Island to Lake Charles. In between these two areas, not a whole lot going on at the moment. With heating and the surface warm front near the coast starting to advance inland, expect to see an increase in showers and some thunderstorms over the next several hours with most of the activity focused east of a line from College Station to Freeport. Warm front will progress through much of the area by mid to late afternoon and expect a lull in the rainfall overnight.

A new front will begin to move into the area from the NNW late on Tuesday into Wednesday and this boundary along with disturbances moving NE from MX and a tropical system off of Baja will produce a good chance of showers and thunderstorms over the area. Rainfall amounts today-early Wednesday will likely average .5-1.5 inches with isolated higher amounts and for many areas west of I-45 that were largely missed by Imelda’s rainfall this will be very welcomed.

Front will progress into the Gulf waters and stall on Wednesday and unlike the last front there will not be a significant push of cold and dry air into the region. Front comes back northward as a warm front Thursday into Friday and Gulf of Mexico really opens up next weekend with a surge of tropical moisture from the Bay of Campeche toward the NW Gulf. NHC is currently monitoring this area for tropical cyclone development (20% chance over the next 5 days) and how organized this system becomes will ultimately determine rain chances for the upcoming weekend into early next week. A strong trough will likely be approaching the area early next week and if tropical moisture from the SW Gulf can become entrained into this feature, heavy rainfall would certainly be possible. Should a more well defined tropical system organize and track toward the Louisiana coast, then much of the heavy rainfall would be carried just east of our area. Plenty of time to watch and fine tune the forecast for this weekend into early next week.

[Kingwood36]

Any more cool fronts in sight?

[srainhoutx]

Any more cool fronts in sight?

Looks like another shot of colder air arrives around the 21st, +/- a day or so. I do see some growing signs of a pattern change shaping up during the last week of October. Time will tell!

[Cpv17]

The Euro & GFS don’t look too promising for rain. I wonder what happened? There was a strong signal for a lot of rain just a few days ago and it was consistently showing it for many runs in a row.

[djmike]

Just picked up a quick 2” in Beaumont. First real rain since Imelda. You’d think 24 days ago plants and grass here would have had enough watering but actually plants and grass were beginning to wither. Doesn’t matter if you get 42” or 2”, its all about the length in between rain to keep things healthy.

[Katdaddy]

A slight chance of afternoon thunderstorm today. The next cool front will push across SE TX late tonight through Wednesday morning with scattered showers and thunderstorms. Highs in the 70s and lows in the 60s for most areas with some 50s N of Houston Thursday and Friday. The weekend currently looks to be mostly sunny with a chance of afternoon thunderstorms. Its still Hurricane Season and the NHC is watching disturbance that will move into the BOC and then WGOM by the end of the week with a 30% chance of development. At this point there will be very little impact as the pattern in place for the weekend will push this disturbance off to the NE away from the Upper TX Coast.

[srainhoutx]

Tuesday morning weather briefing from Jeff:

An area of weak surface low pressure over central America will move into the Bay of Campeche of Wednesday.

Global forecast models have been suggesting that the large area of disturbed weather over central America will drift WNW into the southern Bay of Campeche by the middle of this week and then NW toward the SW Gulf of Mexico by late this week. Recent trends suggest upper level conditions may become favorable for the formation of a tropical system over the SW Gulf of Mexico late this week into this weekend.

An amplifying upper level trough will be approaching TX by late this weekend into early next week and this feature should force any tropical system that forms toward the N and then toward the NE. Latest guidance continues to indicate a tropical system moving across the west-central then north-central Gulf of Mexico this weekend.

It would be extremely rare for a tropical system to impact the state of TX this late in the hurricane season and the upcoming upper air pattern by this weekend favors a turn of any western Gulf of Mexico system toward the NE toward the central or eastern US Gulf coast.

Local:
A cold front will move into the area tonight and this boundary along with pooled high moisture levels will support a good chance of rainfall over the area tonight into early Wednesday. Lines of showers and thunderstorms will be possible along the frontal boundary with rainfall amounts of 1-2 inches and isolated totals up to 3 inches possible. A cooler and drier air mass will move into the region on Wednesday and linger into the later part of the week before moisture begins to return on Friday into the weekend. It is now somewhat uncertain as to how much moisture will move into the area this weekend with the increasing potential for a western Gulf of Mexico tropical system moving across the central Gulf. This feature may take much of the moisture to our east.

[tireman4]

000
FXUS64 KHGX 150950
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
450 AM CDT Tue Oct 15 2019

.SHORT TERM [Today through Tomorrow]...
Radar not quite as active this morning (so far) as it was yester-
day...with only some very light/isolated showers noted across the
the northern counties (streaming from the west) and the over Gulf
waters (moving northward toward the coast). Near-term models seem
to keep the bulk of the activity over these general locations to-
day...with the best POPs not until late this afternoon/tonight as
the next cold front begins its approach.

With rather high PWs (2.2 to 2.4 inches) in place over SE TX, the
best lift looks to be with the cold front itself as it moves into
the CWA. Current near-term progs are indicating a slightly faster
timing of this front (starting 00Z or so), but they could also be
pinging on a prefrontal trof(?). But for now will be keeping with
the going/previous timing of 05Z - 12Z...with the higher POPs be-
ginning across the northern counties this evening. Limited insta-
bilities with the better dynamics/upper support progged for loca-
tions further N of the region should keep the stronger storms out
of the CWA. We`ll likely see decent swaths of rainfall totals av-
eraging around 1/2 to 1 inch with isolated 3 inches possible from
tonight through tomorrow morning. Skies and POPs will be clearing
from the NW to SE by tomorrow afternoon. 41

&&

.LONG TERM [Tomorrow Night through Tuesday Night]...
While cooler/drier weather will be settling in over the region by
tomorrow night, the synoptic pattern is trying to keep things in-
teresting. A trailing upper trof/closed low meandering from far W
to Central TX (behind the main upper trof) along with the shallow
nature of this cool air mass will help with quick the return low-
ish rain chances in for our SW locales and coastal waters by Thur
afternoon/night.

Also of some concern in the extended will be the possibility of a
weak disturbance developing over the Bay of Campeche by late Thur
and Fri. Not expecting any significant issues for SE TX if we are
looking ahead - mainly just marine issues (increased swells, etc)
given the progged upper pattern. 41

&&


.MARINE...
Onshore flow 8-15kts with a few showers this morning then expect
coverage to decrease this afternoon only to redevelop late
evening/early Wednesday. Cold front pushes across the coast 5-8 AM
Wednesday with gusty northerly winds and showers and
thunderstorms. Coverage of storms should wane during the
afternoon/early evening Wednesday as series of s/w ripple overhead
and moisture wanes/shifts south. SCA conditions developing in the
wake of the cold front and persisting well into Thursday.

Will need to keep an eye on the tropical Pacific south of Mexico and
the Bay of Campeche for any tropical development Thursday and
Friday. The upper flow currently in the guidance should steer any
development northeast towards LA/MS/FL but this could bring elevated
seas and stronger rip currents over the weekend.

45

&&

.AVIATION...
Mix of IFR/LIFR over the northern sites and MVFR/VFR over the south.
A few sprinkles/virga traversing the northern counties this morning
and nearing CLL/UTS in the next hour or two. Expecting a fairly
typical evolution today with skies becoming scattered/broken around
2500 ft by mid morning then slowly rising cloud bases by late
morning. HRRR and perhaps ARW lining up nicely with s/w in water
vapor imagery approaching the Big Bend area from Mexico. HRRR
enhances convection over the Hill Country and eventually brings
SHRA/TSRA to CLL around 18-20z time frame with a second cluster on
it`s heels 21-23z. Given the expected soundings with abundant
moisture (PW 2-2.15") see little reason to vary from this scenario.
Cold front pushes south and should swing through the northern sites-
CLL 03-06z and IAH around 09z. Will be trending the TAFs toward this
`wetter` solution with VCSH/VCTS or prevailing SHRA/TSRA after 03z.
45

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 89 63 71 54 76 / 60 80 20 0 10
Houston (IAH) 90 71 74 59 74 / 40 80 60 10 10
Galveston (GLS) 84 74 80 65 76 / 20 80 60 10 10

&&

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

$$

[tireman4]

FXUS64 KHGX 151745
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1245 PM CDT Tue Oct 15 2019

.AVIATION [18Z TAF Issuance]...

VFR to MVFR conditions are currently prevailing at most TAF sites
with the occasional lower CIG impacting mainly the northern sites.
There are some scattered showers that may bring light rain to CLL
or UTS over the next few hours. The main area of concern with this
package is the timing of the anticipated cold front tonight. Winds
are expected to become northerly post front beginning around 05z
at the northern TAF sites, around 09z around the Houston TAF
sites, then around 12z at the coastal sites. Showers and
thunderstorms will accompany the passing cold front, so occasional
lower CIGs and visibilities are possible during the early morning
period. The chance for showers decrease tomorrow afternoon, but
some clouds are expected to linger through the day.

Fowler

&&

[jasons2k]

My high today was 95. Pretty warm for mid-October. Watching that rain moving in.

[DoctorMu]

Bust so far here. However, we got 0.5 in of Sunday. Sprinklers still off but really muggy.

[jasons2k]

Not looking too optimistic. Lots of caveats:

Area Forecast Discussion
National Weather Service Houston/Galveston TX
949 PM CDT Tue Oct 15 2019

.UPDATE...

Big picture concept of the forecast is still on track as a front
continues on its way towards the area. Have played with
temperature trends a little bit to refine as the front draws
nearer - mainly to allow for temps tomorrow to be a bit cooler in
the north, and a touch warmer near the coast.

The near term...is a bit of a different story. Guidance has been
handling the afternoon and evening convection quite poorly, and so
have had to very significantly alter for radar trends. This also
has impacts on severe potential overnight. The front still looks
likely to force convection, and we`re still looking at a scenario
in which there will be plenty of shear, and there`s at least the
prospect of 1000+ MLCAPE. That said, afternoon storms became
outflow dominant and elevated very quickly, so despite at least
one supercell and an upscale growth to a small line of storms,
there was little impact. Not sure how much we`ll be able to
recover, or if the front will be sufficient to keep the line in
balance with its cold pool, but given the previous convection and
the timing of the frontal line of storms, our severe environment
looks pretty, pretty marginal.

Still, it`s worth having some way to get warnings overnight -
preferably a sufficiently loud one, especially farther north
where we`ll probably have a little bit better potential for severe
weather. It`ll make for a nice safety net overnight as we watch
the convection closely.

[ccbluewater]

Picked up about 1.15" overnight!

[Cromagnum]

Unless this backbuilds it's a bust for the south side. Our lawn got a few drops and that's about it

[jasons2k]

Picked up .71” here. I feel fortunate.

[snowman65]

I think I picked up about 2" just driving to work!

[Texaspirate11]

Great rain at the bay!!! Picked up over an inch so far!