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Re: October 2017 - Early Week Cold Front/Warm WX Returns

PostPosted: Tue Oct 10, 2017 7:58 am
by tireman4
FXUS64 KHGX 101025

Area Forecast Discussion
National Weather Service Houston/Galveston TX
525 AM CDT Tue Oct 10 2017

The cold front appears to be making its way into SE TX this morn-
ing...with the wind shift about an hour or so ahead of the actual
colder air. Most of the precipitation associated with this bound-
ary is also lagging well behind it given the current radar trends
so far this morning. Shower and isolated thunderstorm development
is expected to become more widespread through the morning as this
front makes its way toward the coast. Much deeper moisture/higher
PWs just offshore should fuel stronger activity as the cold front
moves into the Gulf late this afternoon/early this evening.

Much cooler temps (than it has been of late) progged for the next
day or so, but the building upper ridge from the east could bring
about the return of above normal temps starting Thurs on into the
weekend. Despite the strong upper ridging...rain chances could re-
turn Fri/Sat as a deepening easterly flow helps to draw in a slug
of some much deeper tropical moisture across the northern Gulf of
Mexico (under the ridge). Extended guidance hinting that the next
cold front is slated for late Sun/early next Mon. 41


Cold front marching southward and prefrontal trough near the coast.
Expect the winds over the coastal waters to weaken this morning
before the front moves off the coast then ramp up to 15-20 knots
with gusts near 25 knots. SCEC for Matagorda Bay and Gulf waters.
Winds remain elevated through Wednesday morning then relax. This
northerly wind will finally draw down our extended period of
elevated tides. At 3 am tides were still running 1 to 1.5 feet above
normal. By late afternoon should be back near normal with the
outgoing tide.

CIGS and VISBY dropping ahead of the prefrontal trough with some
areas down into LIFR to VLIFR. These conditions should improve
rapidly as front moves through and MVFR CIGS of 1500-2500ft should
prevail by 14-15z through mid afternoon. Winds becoming north-
northwest 10-15kts and gusty after FROPA...and a little moreso with
daytime heating. Mid afternoon expecting breaks to develop in MVFR
CIGS and gradual clearing.

Precip chances looking fairly slim over most of the northern half of
the area. Closer to the coast mainly HOU southward thinking rain
chances much higher and VCSH to TEMPO in order for coverage of
showers and a few thunderstorms between 13-18z.

College Station (CLL) 76 58 80 61 87 / 30 0 10 10 10
Houston (IAH) 82 63 80 63 86 / 40 10 10 10 10
Galveston (GLS) 84 70 80 72 85 / 60 20 10 10 10


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.



Re: October 2017 - Early Week Cold Front/Warm WX Returns

PostPosted: Tue Oct 10, 2017 9:21 am
by tireman4
Slowly it is making its way toward us...

Re: October 2017 - Early Week Cold Front/Warm WX Returns

PostPosted: Tue Oct 10, 2017 10:15 am
by CrashTestDummy
Oh, it's through the Pearland/Friendswood area, based on wind direction and pressure, but we're still waiting for that dry air. It's currently 75 deg-F and 82% humidity.

Re: October 2017 - Early Week Cold Front/Warm WX Returns

PostPosted: Wed Oct 11, 2017 7:10 am
by srainhoutx
A very comfortable start to the day with the low 60's across NW Harris County and the upper 50's further North. We should be slightly below climatology temperature wise today across our Region before the winds shift East and then to the SE with an onshore flow into the weekend with warm temperature returning. Will pencil in our next front late Sunday into next Monday.

Looking at the longer range, I am seeing some indications of a possible pattern change as a strong Western Pacific Typhoon re curves into the Northern Pacific and buckles the mainly zonal flow we have seen throughout the Summer. It is not unusual to see this sort of Hemispheric Pattern shift as we get deeper into October. If the ECMWF solution is correct, we may see much cooler air build across the Arctic and Siberia. If the jet stream buckles as some of the longer range deterministic and ensemble guidance suggest, we may see some of that "colder air" arrive in about 20 days or so..' or near Halloween. We will see.

Re: October 2017 - Early Week Cold Front/Warm WX Returns

PostPosted: Wed Oct 11, 2017 9:32 am
by tireman4
FXUS64 KHGX 111034

Area Forecast Discussion
National Weather Service Houston/Galveston TX
534 AM CDT Wed Oct 11 2017

A much cooler/drier start to the day (when compared to yesterday).
With light CAA persisting, high temperatures this afternoon should
remain at to just below climatological norms. However, these lower
temps could be brief. The building upper ridge from the east along
with a light return flow will help warm temps across SE TX through
the rest of the week. Rain chances will remain limited to whatever
(and whenever) surges of higher PWs move in from the Gulf with the
persistent easterly flow. While slightly drier than previous runs,
current progs are still timing rain chances for Fri/Sat, but main-
ly over the coastal waters/SW portions of the CWA.

POPS will be more widespread (but still low) Sun with the arrival
and passage of the next cold front. Much cooler temps expected by
the start of next week. 41


High pressure over North TX will be sliding east and weakening which
will end the CAA over the coastal waters through Thursday. Moderate
north winds of 20 knots will be weakening this morning and SCA flags
through 11 am will be coming down. Winds turn to the east and
northeast tonight/Thursday which should lead to a slow increase in
moisture across the area Friday into Saturday. Isolated showers
possible with the increase in moisture but warm profile aloft will
limit instability. Moisture surge over the Gulf swings west and
should arrive Saturday. By Sunday can`t rule out isolated
thunderstorms as upper trough swings through the Northern Plains and
associated cold front slides southward...probably reaching the
coastal waters Monday and ushering in moderate northerly flow again.


VFR. Mid level clouds 6000-10000 ft will build over the southwest
areas and likely spread northward today. North winds relaxing late
this morning and afternoon. Return flow Friday could lead to a bout
of fog Saturday morning.

College Station (CLL) 78 63 88 68 90 / 10 10 10 10 10
Houston (IAH) 82 63 87 67 89 / 10 10 10 10 10
Galveston (GLS) 82 72 85 76 87 / 10 10 10 10 10


GM...Small Craft Advisory until 11 AM CDT this morning 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...Matagorda Bay...Waters from
Freeport to the Matagorda Ship Channel from 20 to 60 NM...
Waters from High Island to Freeport from 20 to 60 NM.

Small Craft Advisory until 7 AM CDT this morning for the
following zones: Galveston Bay.

for the following zones: Galveston Bay.




Re: October 2017 - Warm WX Returns/Sunday Cold Front

PostPosted: Thu Oct 12, 2017 6:52 am
by srainhoutx
Warm and humid weather returns as an onshore flow off the Gulf begins in earnest today and continues through Saturday. There have been some changes overnight with the timing of our next Pacific Cold Front suggesting an earlier arrival during the day on Sunday and offshore by late Sunday afternoon. A building Ridge to the West should keep NW breezes both aloft and at the surface through at least mid next week offering noticeably cooler and drier air to start the work week. Rain chances look meager at best with possibly some post frontal clouds and a few sprinkles Sunday night into Monday.

It appears to warm back up by the end of next week with another front arriving around the 23rd of October, +/- a day or two.

There are still indications of a possibility that some Canadian Air may arrive near Halloween. That is still to far out to know with any certainty, but I am watching the West Pacific for an increase in Tropical Activity and possibly a strong Typhoon re curving into the North Pacific Ocean buckling the jet stream that may allow a deep full latitude trough to settle over Canada into the United States late October. Fingers Crossed!

Re: October 2017 - Warm WX Returns/Sunday Cold Front

PostPosted: Thu Oct 12, 2017 11:05 am
by DoctorMu
Chamber of Commerce weather the last couple of days and early today. Not looking forward to a surge in humidity without a significant chance of rain...but by Sunday evening, drier and cooler air spills in.

Long term projects look like great weather in late October, naturally when I'm out of town. Next week looks like largely a repeat of this week, but the "cooler" and drier spell is a little longer lasting from Sunday night to Thursday afternoon.

Re: October 2017 - Warm WX Returns/Sunday Cold Front

PostPosted: Fri Oct 13, 2017 5:23 am
by Katdaddy
Drive safe this morning with fog across many areas of SE TX this morning. Expect sunny, warm, and humid weather this weekend before another cold front arrives Monday dropping the lows into the 50s.

Re: October 2017 - Warm WX Returns/Sunday Cold Front

PostPosted: Fri Oct 13, 2017 10:18 am
by srainhoutx
Friday morning briefing from Jeff:

A strong cold front will cross SE TX late Sunday resulting in some of the coolest temperatures since last spring, early next week

Upper air pattern over the US will undergo amplification with a trough developing over the western US into the central plains unleashing a Canadian air mass southward down the plains today into this weekend. Upper ridge over the eastern US and Gulf of Mexico will break down enough to allow this front to push off the TX coast Sunday evening. May see enough moisture return ahead of the front to result in a few showers on Sunday, but don’t think we will see more than 30% coverage.

Post frontal cold air advection will increase Sunday night as NW winds push the colder air mass into the area. Could see some pretty good wind gusts near the coast Sunday night into Monday as the colder air moves over the warm Gulf waters. Highs on Monday will only reach the mid 70’s and lows Tuesday morning will fall into the upper 40’s and lower 50’s over the region.

Unfortunately, the same high pressure ridge building southward across the Rockies this weekend will result in a “Santa Ana” wind event for much of the state of California already dealing with 22 major wildfires. ENE/NE surface winds will be developing Saturday and lasting into Monday which will result in strong downslope component off the mountains across the central part of the state. This results in rapid drying of the air mass and wind speeds can reach 50-70mph through the valleys and canyons producing extreme fire weather conditions. While most typical in southern CA, this event will span much of the state

A slow warming trend will begin by the middle of next week as winds swing back to the ESE and Gulf moisture makes a return to the area.

Re: October 2017 - Warm WX Returns/Sunday Cold Front

PostPosted: Sat Oct 14, 2017 12:08 pm
by DoctorMu
A few showers may develop in the SW HGX area this afternoon, and a broken line of shower accompany tomorrow's cold front. NW winds 15-20 mph possible behind the front and below average temps through Wednesday. Some return flow late next week with the biggest chance of rain Friday. Another cold front is projected next weekend.

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1041 AM CDT Sat Oct 14 2017

Not too many significant changes with this update. Maximum
temperatures along the coast were raised to better match higher
current observations and the current thinking that we could
approach near-record high temperatures across the area today.

Large areas of cumulus clouds are building throughout the area,
especially off the coast, so precipitation changes were kept
higher along the southwest of the are where precipitable water
values are near 1.6-1.7". NAM soundings show a cap around 800 mb,
which should limit thunderstorm capabilities along the coast.
Therefore, isolated showers are expected across the southern half
of the area through this evening.



.PREV DISCUSSION... /ISSUED 651 AM CDT Sat Oct 14 2017/

MVFR/IFR criteria with isolated LIFR/VLIFR across all TAF sites
this morning, besides GLS and HOU currently in VFR. The GOES-16
fog product shows decent coverage impacting many terminals, with
the most dense fog west of the Houston Metro at CLL, LBX, and SGR.
CXO currently sitting at VLIFR, due to dense fog and low cigs
given it`s rural terrain and location. With the help of some
daytime heating and mixing, should see this fog layer lift by mid
morning. VFR conditions will prevail this afternoon, with winds
picking up between 7-10 kts. Similar conditions expected for this
evening, with once again a persistence forecast in store.
Diminished vis and lower cigs in the early morning hours will once
again lower flight categories at most terminals.


PREV DISCUSSION... /ISSUED 406 AM CDT Sat Oct 14 2017/

Similar to yesterday morning, dense fog and low clouds continue
to develop and spread across areas west and southwest of the
Houston metro. Have issued a Dense Fog Advisory through 10 AM CDT
for these areas with several locations reporting visibilities at
or below one quarter mile this morning. Daytime heating and east
to southeast winds increasing into the 5 to 10 MPH range should
allow for the fog to mix out by mid-morning.

Daytime heating will also result in isolated showers or possibly a
thunderstorm to develop in areas generally west of Interstate 45
as convective temperatures in the mid to upper 80s are reached.
Highs are forecast to range in the mid 80s along the coast to
lower 90s inland. These highs, in addition to the unseasonably
warm temperatures being observed across the region this morning,
may mean a few locations may tie or break record high minimum
and/or maximum temperatures for today. More information about
these records are included in the climate section below.

Evening upper air analysis showed mid and upper ridging extending
from southern Texas towards Virginia with a shortwave trough
located over Idaho. As the shortwave trough crosses the Northern
Plains today, it will nudge the upper ridge eastward and also
send a cold front surging southward across the Southern Plains by
tonight. Fog and low clouds are expected to develop again early
Sunday morning ahead of the cold front. This fog is expected to
lift across northern areas as an associated prefrontal trough
arrives Sunday morning and across southern areas with daytime

The prefrontal trough will move across the region during the
morning hours Sunday, resulting in light and variable winds
becoming light and north to northwesterly. The cold front will be
marked by strengthening northerly winds, reaching the Brazos
Valley mid to late Sunday morning, the Houston metro early to mid
Sunday afternoon, and the upper Texas coast Sunday evening. Surface
convergence along the cold front will be minimal as a result of
the prefrontal trough and only expect a thin, broken line of light
showers to develop along the front as it moves south across the
region. Better coverage of showers and thunderstorms is expected
across the coastal waters as a plume of 2 inch precipitable water
air moves into the western Gulf of Mexico.

Temperatures will be tricky on Sunday as frontal timing, cloud
cover, and strength of the cold air advection behind the front
will all be key players in how warm temperatures actually get on
Sunday. Based on anticipated frontal timing, currently advertising
highs in the upper 70s to low 80s across the northern counties
with mid to upper 80s near Interstate 10 and towards the coast.
Otherwise, breezy northerly winds 10-20 MPH are expected Sunday
night into Monday morning. Slightly stronger winds in the 15-25
MPH range will be possible along the coast.

Northwest flow aloft on Monday and Tuesday will promote dry
conditions across the region with temperatures slightly below
seasonal normals with highs in the upper 70s to low 80s and lows
in the upper 40s to low 60s. Shortwave ridging becomes established
by mid-week as a disturbance from the Pacific amplifies over the
Southern Plains, allowing for temperatures to gradually warm to
near seasonal normals. Low rain chances return to the forecast
late next week as return flow resumes.