FEBRUARY 2018 - Roller Coaster WX To End February

[tireman4]

Ever changing forecast. Stay tuned.

[djmike]

What happened to the early Feb arctic intrusions? Thought it was coming in waves and possibly colder than the last big one? One front after another? Looking at nws for us shows a high of 70 today and the 7 day is looking dor more like early spring. Isnt Feb supposed to be our coldest month out of the year climatology? Im confused.

[srainhoutx]

What happened to the early Feb arctic intrusions? Thought it was coming in waves and possibly colder than the last big one? One front after another? Looking at nws for us shows a high of 70 today and the 7 day is looking dor more like early spring. Isnt Feb supposed to be our coldest month out of the year climatology? Im confused.

Let's follow the model volatility in the Medium/Long Range and let that speak about all the sudden uncertainty. These are the Teleconnection Indices Forecasts since late January to today...in the words of Phil Collins (Genesis) Land of Confusion seems appropriate...weather wise...don't you think?

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[srainhoutx]

Sunday afternoon briefing from Jeff:

Overall unsettled pattern of the next week.

Upper air pattern supports cold arctic air mass remaining across the northern US and Canada with little apparent delivery system into the southern plains. A weak backdoor front this afternoon may attempt to erode the low clouds and fog over the region, but the frontal push is weak and may stall between the coast and I-10 this afternoon. Where skies are able to clear (currently most erosion of fog/low clouds is from College Station to Victoria) temperatures will warm well into the 70’s this afternoon while most other areas will remain in the 60’s.

Warm air advection commences on Monday with a chance of light rain and showers along with fog as the surface boundary that enters the area this afternoon returns northward as a warm front. Air mass will gradually moisten Monday night into Tuesday as a stronger disturbance approaches from the NW on Tuesday and Tuesday night with our next frontal passage. Air mass over the region on Tuesday appears to become fairly moist and model soundings show mid level dry air and capping weakening during the afternoon hours especially north of I-10. Could see a few strong thunderstorms develop in that region in the warm sector. Approach of a surface front Tuesday night will likely result in a line of showers and thunderstorms…a few may be strong. Will likely be dealing with sea fog over the coastal locations Monday afternoon into Tuesday as warm air flows over the cold nearshore waters. Rainfall amounts on Tuesday should average .25 of an inch over our SW counties to possibly an inch over our NE/E counties.

Will take whatever we can get at this point to keep fire weather concerns at bay with the dead/dry fine fuels in place.

Cooler and drier conditions likely post front Wednesday and Thursday before winds swing back around to the S on Friday ahead of a potentially fair strong storm system next weekend. Air mass undergoes rapid modification on Friday into Saturday with good moisture advection. A bit early to get into the specifics with this system for next weekend, but air mass looks fairly moist with surface to 300mb layer saturated. Could be looking at some heavy rainfall potential and strong storms with this system….but this is still about 5 days away and the details will likely change some.

[snowman65]

Don't you just love southeast Texas? Lol. At least if you live up north you KNOW what your weather is going to be like all winter long.

[DoctorMu]

Still seeing waves of cool/cold and unsettled wether until the 15, with tongues of cold air lapping down the pine of the Rockies.

Volatility is the word of the day, for sure.

[Ptarmigan]

Code: Select all

000
FXUS64 KHGX 050417
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1017 PM CST Sun Feb 4 2018

.UPDATE...
Drier and cooler air filtering in from the northeast behind a weak
afternoon boundary passage. Despite this...clear skies have allowed
dew point depressions to fall below 3 degrees and dense fog has
developed over the northeastern CWA. Have issued a short fuse
Dense Fog Advisory to alert any travelers of sub mile visibilites
around Sam Houston-Davy Crockett NF/Lake Livingston area. The
drier and cooler air mass upon northeasterlies will aid in
saturating the lower couple of thousand feet below the frontal
inversion and either allow fog or low stratus to form or remain
through sunrise. A reinforcing cool northeast wind with a more
warm and moist southwesterly mid to upper flow will keep overcast
skies around through Monday. This will impact afternoon temperatures
with maxTs likely struggling to reach 60 F. Today`s boundary
becoming stationary offshore...along with PVA riding on through
within the (south)westerlies...will keep slight Gulf/coastal
chances in play for either Monday drizzle or light rain. Patchy
fog chances will still linger over the local bays and nearshore
waters through mid week. 31

&&

.PREV DISCUSSION... /ISSUED 542 PM CST Sun Feb 4 2018/

AVIATION...
Challenging aviation forecast tonight. Drier air is trying to work
it`s way in from the northeast, but moisture trapped under the
inversion may keep 800-2500ft ceilings in overnight - at least
that`s what is advertised in the 00z TAFs. Wouldn`t be overly
surprised to see CLL/UTS see a brief scattering of the clouds,
but all indications are that`ll eventually fill back in. MVFR
ceilings are expected throughout the day Monday...transitioning to
IFR during the late afternoon from south to north as winds veer
to the east and eventually southeast allowing for increasing Gulf
moisture to return inland. 47

PREV DISCUSSION... /ISSUED 355 PM CST Sun Feb 4 2018/
A fairly active period ahead, as a weak boundary is making its
way slowly today to make for a cool Monday. Then a very brief
warmup Tuesday, along with chances of rain and storms increasing
ahead of the next front Wednesday. The temperature rollercoaster
continues for the second half of the week - brief cooling behind
the front, then slow warming until the next front at the end of
the week brings more rain and storm potential to the area. This
active pattern should keep things from getting too out of hand,
we`ll have to keep a wary eye on both frontal passages. Though the
models - taken explicitly - don`t show a ton of potential,
relatively small errors could give us a setup with a shot at some
severe weather in the midweek front, and heavier rain with the
weekend front. Because of that, it would be wise to keep on top of
the forecast this week to stay ahead of any emergent threats with
these fronts.

NEAR TERM [Through Tonight]...
While it`s somewhat muddied in the obs, only shown really well by
a subtle wind shift and change in dewpoints, satellite makes it
abundantly clear where a weak front is on the northern edge of our
area as we sharply transition from the low overcast over our
corner of Southeast Texas to brilliantly blue skies on the other
side of the front. Because of that, it`s really, really hard to
justify calling this a cold front because the sunny skies have
allowed temperatures to rise higher than they are here on the
"warm side". Because of that, the boundary has become nearly
stationary, only dragging south as drier air filters in, mixes,
and erodes the low clouds.

Anyway, as the sun goes down and we see the reverse, with the
clearer skies cooling off faster, we should see a more significant
push of the front to the south, ushering in cooler, drier air and
offshore winds. It probably won`t be a very significant
difference, perhaps only enough to briefly end sea fog in the
waters for a bit as we approach dawn. Also, lows overnight should
be at least modestly cooler, with greater impacts well north of
Houston, and lesser cooling near the coast.

SHORT TERM [Monday Through Tuesday Night]...
Our period of offshore flow should be brief, with winds turning
back to be more easterly tomorrow and even southeasterly Monday
night. This will bring an influx of moisture right back in, and
the return of sea fog on Monday or Monday night, which may manage
to push onshore into some coastal areas. While there`s pretty
strong certainty in the return of sea fog, if the push will be
powerful enough to shove on land is a little more of an open
question. Despite that, we should at least look for a bit of
warming, with Monday night lows up, and Tuesday highs in the upper
60s to low 70s. Some spots near the coast southwest of Houston
may make a run for the middle 70s, even. However, with moisture
and onshore flow comes the return of rain chances - probably
fairly low Monday night, but increasing for Tuesday.

Tuesday afternoon, indeed, could be somewhat interesting. Pretty
solid agreement for at least some modest instability, and both the
GFS and Euro (amazingly out CAPEing the NAM) build 1000-15000 j/kg
of CAPE southwest of Houston, and turning in the low level winds
suggests a good bit of low shear and helicity. However, this
potential instability may remain just that - potential. The low
level jet looks to be fairly veered, which generally induces some
capping, the front is far to the north yet, reducing low level
convergence, and the upper jet is also far to our north, which
won`t help support upward motion, either. Something to keep an
eye on, but will need some changes in the atmosphere aloft to
really allow for much severe potential.

LONG TERM [Wednesday Through Sunday]...
Wednesday may be interesting, as well. the GFS is a bit slow with
the front, making it late enough for modest instability to build
again when the front rolls through, and could make for some
fireworks on the front. The NAM and Euro - and our forecast - show
a bit of a different scenario - quick with the surface front, but
lagging with the 850 front - this would allow for elevated CAPE
to emerge as warm air advection continues just aloft, and we could
see some elevated action behind the surface front. The
disconnection from the surface would limit the threat from severe
winds and tornadoes, but with enough elevated convection and
strong deep shear, we could see a shot for some hail in the
strongest storms. Because this scenario remains a bit iffy, we
concur with SPC in holding back on hitting this potential too
hard, but it is a plausible - if unlikely - outcome. Stay tuned
for any changes in the coming days.

After that, we look for the cooling/warming yo-yo for the second
half of the week. Low rain chances are expected, and with the
guidance coming in with less clearing behind the front than
before, have moderated the swing in temperatures. Spots way up in
Houston County may manage to dip into the middle 30s Wednesday
night, but freezing temps look less likely than the did before.

The next front looks...very difficult to forecast. The operational
GFS looks particularly goofy, as it creates an upper trough
bonanza around the Pacific coast, squeezing in the western ridge.
This slows up the front, which becomes weak and doesn`t make it to
our area until Sunday night. In the meantime, a little coastal
low/trough spins up and gives us some rain on Saturday. It`s
just...weird. I don`t like it - heck, the GFS` own ensemble
doesn`t even like it. The op run would be one of the driest
members, and IAH`s mean QPF by 192 hours is 1.6 inches (with the
wettest member at 2.82 inches) against an operational QPF of 0.91
inches. I`m much more a fan of the Euro, which builds a robust
western trough, allowing for northwest flow to power the front in
Sunday morning/early afternoon, and like the GEFS, is notably
wetter. Still, because of the wide range between the GFS and Euro,
I`ve spread the PoPs out some for the end of the forecast period,
as there is much time for the details to change. Another thing
worth noting - temperature forecasts are similarly impacted, with
the Euro considerably warmer than the official forecast at this
time range. I`ve nudged temps up from the last shift, but if the
Euro does indeed have the better handle on this timeframe, the
forecast will have to move up even more. Again, stay tuned.

MARINE...
Patchy fog will over the Gulf waters should briefly come to an
end as the cold front pushes out into the waters and boosts winds
to SCEC for 8-14 hours NE 15-20knots. The front stalls and comes
back quickly and currently upper 60 dewpoints are lurking 100+ nm
offshore. With the return of the warm front Monday night/Tuesday
morning the marine areas should have another round of sea fog that
continues until a cold front blows through Wednesday 4-9 pm. SCA
winds possible in the wake of the cold front. 45

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      42  61  54  72  48 /  10  10  40  50  70
Houston (IAH)              51  60  55  73  58 /  20  10  40  50  70
Galveston (GLS)            54  58  58  67  58 /  20  20  40  40  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Dense Fog Advisory until 3 AM CST Monday for the following
     zones: Houston...Madison...Polk...San Jacinto...Trinity...
     Walker.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 10 AM CST Monday for
     the following zones: Coastal waters from Freeport to the
     Matagorda Ship Channel out 20 NM...Coastal waters from High
     Island to Freeport out 20 NM...Waters from Freeport to the
     Matagorda Ship Channel from 20 to 60 NM...Waters from High
     Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...31

http://forecast.weather.gov/product.php ... glossary=1

[srainhoutx]

Active rollercoaster pattern continues throughout the week with rain chances increasing tonight as a Coastal wave associated with a warm front returns N in advance of a currently stalled Arctic Boundary across N Central Texas on N E into the Tennessee Valley. Fog and drizzle return tonight beneath a CAP with winds slowly veering Easterly. Temperatures today will remain stuck in the 50's to 60's holding steady or rising slightly overnight as the warm front advances inland.

Tuesday looks wet as PW's increase as a surface low tracks W to E along the stalled boundary to our N. Upper level disturbance riding the sub tropical jet comes into play later on Tuesday increasing the chance for showers and possibly some thunderstorms. Dynamics don't look too impressive, so severe storms look marginal at best.

Tuesday night into early Wednesday morning the front to our N slowly advances towards the Coast with increasing showers and thunderstorms with a chance of some small hail, but dynamics still look marginal in the SW flow associated with that pesky noisy sub tropical jet overhead. The front should clear the Coast Wednesday, but concerned post frontal light rain and clouds will linger into Wednesday night possibly into Thursday if the NAM solution proves to be correct.

Rain chances increase Friday as the next front nears from the NW with some potential of heavy rainfall Friday afternoon into early Saturday. I still see timing issues in the various computer schemes regarding the timing of the front, how cold we get behind that front and does it actually clear us out on Sunday with drier air filtering in. Yesterday shows just how difficult it is to forecast sensible weather even 6 to 12 hours in advance with a noisy sub tropical jet overhead in February.

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[srainhoutx]

NWS Houston‏Verified account @NWSHouston
2017 started out so warm and 2018 has been just the opposite. The average temperature over the first 35 days is between 8 and 11 degrees cooler this year as opposed to last year.

[snowman65]

Looks like a February fiasco....I'm ready to move on to spring now.

[tireman4]

Happy Weatherperson's Day to all of our pro mets ( Andrew, Srain, Wxman57, Blake, Belmer, Brooks, Mcheer and countless others I have missed) and amateurs alike. Thank you for all you do to make this board rock.

[srainhoutx]

The afternoon Forecaster adjusted CPC Day 6 to 10 Outlook suggests below normal temperatures across the Central United States and above normal precipitation for most of our Region likely due to that noisy sub tropical jet overhead and a bit of troughiness near El Paso. Below are the Day 8+ Super Ensemble Analogs.

[DoctorMu]

The afternoon Forecaster adjusted CPC Day 6 to 10 Outlook suggests below normal temperatures across the Central United States and above normal precipitation for most of our Region likely due to that noisy sub tropical jet overhead and a bit of troughiness near El Paso. Below are the Day 8+ Super Ensemble Analogs.

srain: Great summary. That's exactly what I'm seeing a deep trough intersecting with a noisy SJT for the next 2 weeks. Four Season in one Day (or week) kinda stuff.


If you don't like the weather, just wait a few hours!

[srainhoutx]

Fog is getting thick out there reducing visibility for the morning commute. Bush is down to a 1/4 of a mile, so allow a little extra time this morning. Light rain/drizzle will make for wet roads as well.

[srainhoutx]

The upcoming weekend is looking very wet across portions of SE, E Texas into Louisiana. Concern growing for the potential of heavy rainfall as Coastal low/trough organizes near Brownsville/Corpus Christi with a deep SW trough seen on all the Global Ensembles as well as a Baja low meandering across Mexico into Texas. Embedded disturbance riding the sub tropical jet suggest rainfall with possibly some heavy thunderstorms develop Friday and continue into Saturday. Rainfall could continue into Sunday before we finally see a brief break before another front approaches. Rollercoaster Pattern continues.

[Katdaddy]

Safe travels and take your time with the morning commute. A messy morning across SE TX and the Upper TX Coast with a Dense Fog Advisory in effect until 10AM this morning and some showers moving across the Houston-Galveston areas.

Rain sums up the weekend heavy rain potential quite well.

[redneckweather]

Time to cut back plants and prune the crepe myrtles with no big freezes in sight. Signs of Spring will start to pop up in the next couple of weeks. Hold tight, Spring is just around the corner!

[snowman65]

What happened to the arctic weather that was possible during the early to mid Feb time frame? I was looking like a pretty good setup. What changed to bring us all of this cool, rainy miserable weather?

[Cromagnum]

I'm definitely going to be sad if it's already spring. Need to keep the heat away as long as possible.

[srainhoutx]

Tuesday morning briefing from Jeff:

Soggy weather pattern for the next several days.

Surface warm front along the coast this morning is creeping inland allowing 60 degree dewpoints to reach the coast. Warm and humid air mass over the cold nearshore waters is resulting in dense sea fog forming along the coast and spreading inland. Area radars show scattered showers in the developing warm air advection regime over SE TX and surface obs show the next cold front over OK moving toward N TX. Overall pattern today will be foggy with period of passing showers and maybe a thunderstorm as the coastal warm front moves inland and the surface cold front over the southern plains moves southward into the region tonight.

While SPC has outlooked the northern portions of the area for a few strong thunderstorms this afternoon and evening for hail, think this threat is low given the parameters in place. Rainfall amounts will average between .25 and 1.25 inches over the region with the greatest amounts likely focused over the northern and eastern portions of the region.

Cold front will slice through the region tonight with temperatures falling on Wednesday. Upstream air mass is fairly cold and expect temperatures to fall into the 40’s on Wednesday and hold throughout the day. 850mb front is slow to move southward and WSW flow aloft will result in overrunning behind the surface cold front. Elevated instability may result in a few thunderstorms in the post frontal air mass on Wednesday and some of these storms could produce some small hail.

Drier air mass moves into the region Wednesday night and Thursday and skies may briefly clear before the next storm system approaches this weekend.

Coastal trough will begin to develop early Friday and clouds will thicken and lower during the day on Friday with moisture surging back inland. Could even see scattered showers develop by mid to late afternoon on Friday as the air mass saturates. Next storm system will approach this weekend along with a fairly cold air mass from the north. Global models are not handling the timing of this next front very well with difference from late Saturday to late Sunday which will have large temperature impacts for the region. Forecasted upstream air mass behind this front looks very cold so there appears to be some major temperature forecast challenges for Sunday. Showers and thunderstorms look likely through much of the weekend with warm air advection in place over the area at least prior to the frontal passage. Appears rains will continue in the post frontal air mass into early next week. Will need to keep an eye on temperatures by Sunday evening especially up north from College Station to Huntsville if the colder and faster global models look to verify as the freezing line could dip toward those areas.