April 2023

[Cromagnum]

Pretty dark near Pearland.

[Cpv17]

Pretty dark near Pearland.

There’s a pretty big storm that just blew up near you. Looks like it skipped over you from an outflow boundary and blew up south of you in Danbury. Figures.

[Cromagnum]

Pretty dark near Pearland.

There’s a pretty big storm that just blew up near you. Looks like it skipped over you from an outflow boundary and blew up south of you in Danbury. Figures.

Yeah, we got a tiny bit of it before it pulsed down.

[tireman4]

000
FXUS64 KHGX 131128
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
628 AM CDT Thu Apr 13 2023

...New AVIATION...

.SHORT TERM...
(Today through Friday Night)
Issued at 338 AM CDT Thu Apr 13 2023

Our "friend" over the northern Gulf is making its way to the
northeast, headed off towards the Mobile/Pensacola area. In its
place, a short period of ridging should take command today and
much of tomorrow, before the ridge axis aloft pushes off to our
east later tomorrow afternoon.

As a result, today should feel very much like yesterday - just
take out the afternoon showers and storms with the Gulf low out of
the picture, and a few more degrees tacked onto the afternoon
high. So, while yesterday saw only a few isolated hot spots reach
80 degrees, I think a noticeable band of highs at or slightly
above 80 should emerge on the coastal plain this afternoon, with
those on the water and farther inland still topping out in the
upper 70s.

Though winds are light and variable now, onshore flow should
establish itself this afternoon, and prevail through the night and
really straight on until Saturday`s cold front moves into the
region, but that`s something for the long term forecaster to
discuss. I`ll hold myself to gradually increasing dewpoints. As
usual, this is going to bump up overnight lows some tonight, and
even more tomorrow night as dewpoints rise to above 70 degrees.
So, hopefully everyone enjoyed our stint of overnight lows around
and even a little below seasonal averages, because those are
heading on up. Tonight, I have lows in the upper 50s to lower 60s,
except north of Lake Livingston, where we could still see some
middle 50s as dewpoints begin to rise there latest. At the coast,
we may struggle to get much below the middle 60s. Tomorrow night,
push things up a little more - north of I-10 or so in the middle
to upper 60s, and south of that it will be difficult to fall below
70 degrees. With the higher floor, more widespread highs in the
lower 80s can be anticipated, except in the northernmost portion
of the area that may hang back in the upper 70s.

Speaking of things like increasing moisture and a cold front in
the long term, we`ll have more water-related implications from
onshore flow and increasing moisture as well. Patchy fog is
cropping up around the area early this morning, and we can likely
expect more of the same late tonight. We`ll trade higher dewpoints
for slightly stronger winds, so I`m not anticipating a widespread
fog event, but should see some crop up in local problem spots. As
moisture deepens, we can also look for some isolated to scattered
showers, mainly in the far west and north tomorrow afternoon and
evening. Anything to the west will be on the fringes of a deeper
moisture channel farther down the coast, and will likely be more
along the lines of lighter showers. Up north, we may see the
remnants of any storms that fire farther to our northwest before
they fizzle out in our less supportive environment.

There`s a very outside shot that a strong to severe storm manages
to make it to the northern edge of our forecast area, but more
likely, it`ll be rapidly weakening thunderstorms or showers. But,
because of this low chance, we are nicked by SPC`s Day 2 marginal
risk area. Sorry, Bryan, Madisonville, and Crockett. A reminder to
keep an eye on activity to the northwest on Friday, but not
necessarily a big concern - and certainly a lesser issue to our
area than a more direct (but still conditional!) threat for
stronger storms on Saturday. I`ll turn it over to the long term
for more on that...

&&

.LONG TERM...
(Saturday through Wednesday)
Issued at 338 AM CDT Thu Apr 13 2023

Increasing warmth and humidity will continue into Saturday, which
may prove to be our first 90 degree day for many locations in 2023.
Current forecast calls for upper 80s for most of the area given the
influence of a weak ridge aloft as well as persistent WAA at the
surface, but recent NBM probabilistic forecast indicates the
potential for highs as high as the lower 90s. Despite the notability
of this heat, the main weather story in the extended period
continues to surround the approach of a cold front later in the day
on Saturday. While this feature is expected to bring fairly
widespread rainfall to the area, the chances for severe storms still
remain questionable. While SB instability is expected to be ample
(SBCAPE values of 3000-3500 J/kg during Sat afternoon) and midlevel
lapse rates will reach approximately 8 degC/km, effective shear in
the range of 10-15kts will also significantly limit the potential
for supercell storms and inhibit potential hail growth. Nonetheless,
with the significant instability still present, it`s not out of the
question that we see a couple of stronger storms on Sat late
afternoon/evening.

As the front pushes offshore on Sunday, clearer and cooler
conditions will take hold as surface high pressure settles into the
area with daytime highs dropping back into the mid/upper 70s and
overnight lows in the upper 40s/lower 50s. As this area of high
pressure shifts to the east during the day on Monday, we`ll see a
relatively quick redevelopment of moisture return as highs gradually
increase over the course of the rest of the week. Afternoon temps
break into the lower 80s on Tuesday and the mid/upper 80s by
Thursday, with increased cloud cover bringing a return to overnight
lows in the mid/upper 60s beginning on Tuesday night. The approach
of a midlevel shortwave early on Wednesday will bring our next
chance of widespread rainfall to the area.

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 628 AM CDT Thu Apr 13 2023

VFR for the large majority of the area this morning, but patchy
fog causing intermittent issues at rural, foggy terminals (UTS,
CXO, SGR, LBX). Those should resolve by 15Z, leaving mostly sunny
and VFR across the area with light, east winds becoming more
southeasterly through the day. Light and mostly clear again
tonight, with patchy fog cropping up again. Low confidence on
impacts to specific terminals (but probably the usual suspects),
so taking a soft hand with VSBY restriction right now.

&&

.MARINE...
Issued at 338 AM CDT Thu Apr 13 2023

A return to onshore flow is expected today, with wind speeds
increasing ahead of the approach of a cold front on Saturday
evening. This front will bring with it the potential for widespread
showers and storms, with a few stronger storms possible on Saturday
night. As the front departs the area, moderate to strong NE winds
will develop on Sunday, likely requiring a Small Craft Advisory. As
surface high pressure begins to move out of the area by late Monday,
onshore winds will return relatively quickly and increase to caution
thresholds by mid-week.

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 78 59 79 68 / 0 0 10 20
Houston (IAH) 80 61 82 70 / 0 0 10 10
Galveston (GLS) 74 69 77 72 / 10 0 0 10

&&

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

$$

SHORT TERM...Luchs
LONG TERM....Cady
AVIATION...Luchs
MARINE...Cady

[tireman4]

AVIATION...
(18Z TAF Issuance)
Issued at 1206 PM CDT Thu Apr 13 2023

VFR conditions along with light and variable winds will prevail
through the first half of the afternoon. In the late afternoon,
winds shift to southerly and pick up slightly to around 5 to 7
knots. West of I-45, winds hold steady around the same speed while
east of I-45 winds become light and variable again. The patchy fog
potential is a bit iffy as slightly higher winds along with
increasing cloud cover from the west could inhibit its
development. For now, still keeping the trend of decreased
visibilities for CLL/UTS/CXO/SGR/LBX. Any fog that develops will
burn off quickly after 14Z/15Z with southerly winds picking up to
around 10-12 knots with gusts around 15-18 knots into the
afternoon. Expect cloud cover to gradually increase throughout the
day from west to east. A few models are indicating MVFR ceilings
as early as Friday afternoon as moisture steadily climbs.

Batiste

&&

[Stratton20]

What an absolute picture perfect Thursday! Just got my Aggie Ring at Aggie Ring Day!

[Ptarmigan]

More than 25 inches of rain fell in Fort Lauderdale area.

Tomer Burg
@burgwx
I've made numerous animations of extreme mesoscale flash flooding events in recent years -- August 2021 in Tennessee, Hurricane Ida in NJ, just to name a few.

None have been as extreme in intensity *and* duration as what occurred in Fort Lauderdale, FL yesterday.

https://twitter.com/burgwx/status/1646598030513303552

[tireman4]

000
FXUS64 KHGX 141126
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
626 AM CDT Fri Apr 14 2023

...New AVIATION...

.SYNOPSIS...
Issued at 408 AM CDT Fri Apr 14 2023

Onshore winds have returned to the area, which will bring more
moist air back to the region ahead of a cold front on Saturday.
This sets us up for a day with lots of instability present to fuel
any storms that may develop. However, not everything points to
stormapalooza on Saturday - indeed, there are enough mixed signals
that there are questions about both the number and intensity of
storms across Southeast Texas Saturday afternoon and evening.

The main thing to takeaway for your weekend plans? Know that
strong to severe storms are possible, but questionable (think
something like a 5-15 percent chance of a severe storm within any
given county). For those Saturday activities, it`s great
foresight to ensure you can receive weather warnings if any are
issued, and if your plans for the day/evening are outdoor ones,
know a way to quickly get to sturdy shelter should the atmosphere
end up ruining the fun. Or, you know, make Saturday an indoor day.
It`ll be pretty warm anyway, while Sunday will have fair weather
and more seasonable temperatures. This will give you the best
balance of enjoying your weekend and staying safe should you end
up experiencing a severe storm.

&&

.SHORT TERM...
(Today through Saturday Night)
Issued at 408 AM CDT Fri Apr 14 2023

Another night with a mostly clear sky across the area, and patchy
fog cropping up in known trouble spots. However, rather than a
fully clear sky, we`ve had just enough cirrus sailing overhead and
winds that are slightly too strong to keep increasing dewpoints
from making fog a bigger problem that it maybe could be. With
patches of cirrus and just enough wind hampering ideal
radiational cooling, I don`t anticipate a big eruption of fog,
though I expect we`ll continue to see patches pop up
intermittently, especially in locations known to fog easily, when
the sky has no clouds overhead, and where winds temporarily go
slack.

This morning should also start warmer - with the disruptions to
cooling and the higher temperature floor that comes from dewpoints
beginning to increase thanks to the return of onshore flow, we
should be starting more in the upper 50s and lower 60s. This will
help us see more locations reach to around and just above 80
degrees this afternoon - rather than just the warm spots on the
coastal plain, most of the area should manage to at least get
within a couple degrees of the 80 mark, and likely reach it. The
one exception would be on the coast - Gulf waters are still in the
low 70s, so highs should be lagging behind a bit in the 70s.

On top of the warmer temps, we`ll also start to think about the
return of some very low rain chances along the western edge of the
area. Across Southeast Texas, the moist return flow should only
mean the development of more afternoon clouds. However, satellite
estimates of precipitable water already have PWAT at 100 percent
of normal west of the Brazos, and this area will be closer to the
main channel of incoming moisture farther down the Texas coast. As
a result, I wouldn`t be surprised to see a couple showers...maybe
even a weak thunderstorm pop up this afternoon. Even here, the
large majority of folks will be looking at a mostly cloudy day
with no rain, but the potential is enough for me to sneak in that
slight chance of rain right along the western edge of the forecast
area.

What - if any - little activity occurs this afternoon will blink
out of existence pretty quickly as the sun goes down, and our
focus will turn to the incoming cold front on Saturday. Timing of
the front seems to come in just slightly later day after day, and
now confidence is increasing in having the ingredients for severe
storms being a little misaligned. This probably won`t completely
eliminate a severe threat. HREF probabilities for exceeding 2000
J/Kg of SBCAPE are over 90 percent area-wide as early as 10am.
HREF mean SBCAPE exceeds 3000 for all of Southeast Texas and is
over 4000 in the juiciest spots. There`s certainly no shortage of
storm fuel here. But, we`re also somewhat lacking in shear. We`ll
struggle (and in most places, fail) to reach 30 knots of bulk
shear, which indicates that even if storms do get going, storms
will have a hard time keeping an organized updraft. Instead,
whatever storms we get may live hard, but give out quickly. This
doesn`t preclude a brief hailer or a small burst of damaging
outflow winds as a storm collapses, though it does tend to
indicate an overall limit to storm potential. That we continue to
look at a marginal risk from SPC in the Day 2 outlook is not a
surprise in this scenario.

A weakness in the shear profile isn`t the only conflicting factor
here. There appears to be some pretty good consensus in the
guidance that the main moisture axis passes through a little
early; more Friday night/Saturday morning, as does the potential
for a shortwave trough. This would help boost chances for pre-dawn
and morning showers, but as they are on their way out while
instability is increasing and the cap erodes, it may hamper
convective development ahead of the front. HREF mean SBCIN does
disappear by midday, so we could see pre-frontal storms get going,
but the mismatch with the moisture axis and upward motion support
aloft won`t help, and it seems to be showing in fairly pessimistic
CAM models. We`ll get a more obvious source of mechanical forcing
on the front, but it may now be tardy enough that it shows up
after peak heating and as instability is beginning to diurnally
decline. Again...none of this means that storms aren`t going to
happen and I`m not sounding an all clear by any means. This does
explain, though, why any severe threat on Saturday will be
conditional and lower expectations for both number and intensity
of any storms that could develop Saturday afternoon and evening.

Beyond storm potential, another thing to look at for Saturday is
heat. As onshore flow persists, low temps should get stuck closer
to 70 degrees Saturday morning - a few degrees cooler up north, a
degree or two warmer at the coast. Between this and a front that
may not reach the area until the late afternoon, not make it to
Houston until late evening, and the coast until around midnight,
we are instead looking at a full day of southwest flow. Clouds
will hamper heating some, as might any early day showers or
storms, but we should still get pretty toasty for mid-April. I`ve
got mid to upper 80s for the large majority of the area away from
the moderating influence of the Gulf. Some spots way up north may
only reach the lower 80s.

Finally, once the front is through, we should see gusty north
winds develop, sweeping in cooler and drier post-frontal air. Peak
winds could be up around 20 mph, with occasional gusts to around
30. This will help drive temperatures that are in the 80s at
sundown into the 50s (or lower 60s at the coast) around sunrise.
So if you missed those cooler nights we had not too long ago,
we`re setting up to get at least a short stint of that back. But
that is for the long term to discuss...

&&

.LONG TERM...
(Sunday through Thursday)
Issued at 408 AM CDT Fri Apr 14 2023

Dry cool weather will prevail Sun in the wake of the cold front with
moderate to strong northerly winds in place. Highs should range from
the lower and mid 70s across SE TX. As the surface high settles over
the region Sun night, we may be in for some rather cool temperatures
(compared to normals). Lows could fall into the mid to upper 40s for
our northern counties (including the Brazos Valley) to the lower 50s
for the rest of the CWA (including H-town proper).

Slowly warming conditions will be on tap for Mon as this high begins
to nudge east with time. And by Tues, look for the return of onshore
winds as this system moves into the NE Gulf. The rest of the week is
likely going to continue with this warming trend along with increas-
ing low level moisture. Rain chances are forecast to return by Tues/
Tues night as a series of vigorous shortwaves (moving in from the W)
help to flatten the ridging aloft. These features combined with day-
time heating, increased low-level moisture and perhaps the seabreeze
could be enough to support the idea of scattered showers with isola-
ted thunderstorms. POPs may need to be extended into Weds (depending
on the timing of these disturbances).

Otherwise, per that aforementioned warming trend, highs on Mon from
the upper 70s and lower 80s are progged to warm into the mid 80s by
Thurs/Fri. Overnight lows should follow a similar path as they warm
from the 50s Mon night into the upper 60s to lower 70s by
Thurs/Fri.

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 626 AM CDT Fri Apr 14 2023

Patchy fog again this morning, but any TAF sites that have seem
fog appear to be on an improving trend. Still some potential for
next several hours, but not high enough confidence to even TEMPO
at this time. If anywhere, LBX and CXO would be prime suspects.
Gusty south winds develop later this morning, become the primary
issue. Though gusts may drop off after sundown, expect south winds
to stay up. Instead of fog, this creates expectation for MVFR CIGs
late.

&&

.MARINE...
Issued at 408 AM CDT Fri Apr 14 2023

Generally light to moderate onshore winds will prevail today in
advance of the next cold front that is expected to push through
into the Gulf waters tonight. The front could produce showers with
some isolated thunderstorms followed by strong gusty north winds
(~25kt) and building seas (5-8ft) in its wake. Small Craft
Advisories will be required. Onshore winds will resume late
Mon/early Tues. The extended forecasts are indicating the
development of a long fetch of moderate onshore winds setting by
the middle of next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 80 69 86 54 / 20 20 20 10
Houston (IAH) 82 71 88 57 / 10 20 40 40
Galveston (GLS) 78 72 83 64 / 10 20 30 30

&&

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

$$

SHORT TERM...Luchs
LONG TERM....41
AVIATION...Luchs
MARINE...41

[tireman4]

Kinda off topic, but....


Glen Powell is in talks to co-star opposite Daisy Edgar-Jones in Twisters, a new chapter to the 1996 box office hit for Amblin Entertainment and Universal Pictures. Lee Isaac Chung is on board to direct from a script by Mark L. Smith. The film will be co-financed by Warner Bros.

[tireman4]

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1230 PM CDT Fri Apr 14 2023

Persisting southerly winds will continue to bring more humid air
and clouds into the region. MVFR ceilings will continue to develop
and spread north-northeast across SETX this afternoon and
evening. There will be some BKN VFR cigs at times, but the general
trend is MVFR conditions through the end of this TAF cycle. A few
disturbances will move over the region overnight, bringing rain
and storm chances across the terminals. Confidence in timing and
location is still low to medium, given differences between hi-res
models. As of now, have included VCSH after 08Z Saturday, but
showers could develop as early as 05Z Saturday. Winds will
generally remain from the south between 10 to 15kts.

&&

[jasons2k]

Kinda off topic, but....


Glen Powell is in talks to co-star opposite Daisy Edgar-Jones in Twisters, a new chapter to the 1996 box office hit for Amblin Entertainment and Universal Pictures. Lee Isaac Chung is on board to direct from a script by Mark L. Smith. The film will be co-financed by Warner Bros.

I still can’t believe Bill Paxton passed away.

[DoctorMu]

Kinda off topic, but....


Glen Powell is in talks to co-star opposite Daisy Edgar-Jones in Twisters, a new chapter to the 1996 box office hit for Amblin Entertainment and Universal Pictures. Lee Isaac Chung is on board to direct from a script by Mark L. Smith. The film will be co-financed by Warner Bros.

I still can’t believe Bill Paxton passed away.

Truly.

The original Twister was a landmark event, signifying our scientific progress in better understanding the complexities of weather, especially severe weather.

[Stratton20]

I have a feeling this twister spinoff is going to be a flop, some classics should just be left untouched, just my opinion on this gem of a weather movie

[Cromagnum]

Nice storm from San Antonio was headed right for us, then poof right as it got to the county line. Then exploded right after it got past us. Naturally.

[jasons2k]

Update posted on Space City Wx:

More recent data suggests a higher chance of storms this evening
April 15, 2023 at 9:02 am by Eric Berger
Good morning. We’re jumping in here with a quick post on Saturday morning as we’re getting more data about atmospheric conditions later today and tonight. Essentially, what we’re seeing is an atmosphere more conducive to thunderstorms and potentially severe weather than we expected.

To be clear this is not an all-out alert. NOAA’s Storm Prediction Center has the entire Houston region placed under only a “slight” chance of severe weather for today and tonight. But that is higher than we anticipated yesterday.

Severe storm outlook for Saturday and Saturday night. (NOAA)
A warm day in the upper 80s today will help provide atmospheric heating. This may support the development of isolated showers and thunderstorms from 3 to 6 pm in the vicinity of downtown or areas north of the city. Then there may be a bit of a reprieve before a cold front moves through the area from west to east.

The primary time for concern from storms will run from 7 pm to midnight, as storms generally progress eastward across the area. The front will provide some pretty vigorous uplift and instability, but these storms will be hit or miss. Some areas will get no rain, whereas small pockets of the city or greater Houston region may pick up 2 to 4 inches of rain rather quickly. Embedded in these storms is the threat of strong thunderstorms, damaging winds, and hail. On the scale of excitable dogs—on which my two are invariably a 10 when there is lightning or fireworks—I’d call tonight a 7.5 until things settle down by or before midnight.

The bottom line is that this evening will bring the threat of severe weather to Houston, and based on our latest data we think it is prudent to be weather aware. Things may be just fine, or there may be an hour or two of bedlam. Have a good radar app available to check conditions in your area. We are still highly confident that things clear out overnight, bringing the region some drier, sunny, and most pleasant weather for Sunday and Monday.

[Cromagnum]

Sounds like southern areas shafted again based on that.

[Cpv17]

Sounds like southern areas shafted again based on that.

The HRRR (which is my personal favorite short range mesoscale model) actually looks decent for both me and you. Shows some pretty explosive development beginning around 3-4pm.

[don]

Yep some people may see some hail this evening from a few supercells.

[Cpv17]

Yep some people may see some hail this evening from a few supercells.Screenshot 2023-04-15 at 10-23-58 Models HRRR — Pivotal Weather.pngScreenshot 2023-04-15 at 10-24-04 Models HRRR — Pivotal Weather.png

Yep. Those are the types of storms that can produce some pretty big hailstones right there.

[Stratton20]

It appears a return to wet weather becomes established over the state next week ( as well as tonight) as multiple disturbances move across the region with plentiful moisture to work with, as per usual timing and amounts are up in the air, but their is good agreement for at least a chance of scattered thunderstorms starting next week and beyond