Re: February 2020
Posted: Wed Feb 19, 2020 1:45 pm
000
FXUS64 KHGX 191806
AFDHGX
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1206 PM CST Wed Feb 19 2020
.AVIATION [18Z TAF Issuance]...
Expect scattered showers and IFR CIGs to continue through tomorrow
morning across the area. Through the rest of the day today, the
heaviest rain showers will remain north of the area along a
boundary. This boundary will move through late tonight bringing a
better chance of precipitation, but it will be weakening as it
pushes through. So, the sites that have the best chance of
getting SHRA will be CLL, UTS, CXO, and IAH. Overnight tonight
CIGs will remain around 5000 to 7000 feet, but ceilings do rise
tomorrow afternoon to MVFR as the front moves off the coast.
Breezy northerly winds will be expected starting tomorrow
afternoon through tomorrow night.
&&
.PREV DISCUSSION /Issued 547 AM CST Wed Feb 19 2020/...
DISCUSSION...
The front has finally passed through all of Southeast Texas and
has pushed out over the Gulf, finally bringing an end to the fog
event for the entire area, with the exception of some Gulf waters
several miles offshore.
Despite this, look for rainy conditions to continue. Like
yesterday, expect the most rain north of Houston - perhaps from
roughly Brenham to Livingston northward. For the rest of the area
south of that line, another cloudy day with sprinkles and mist are
likely, along with some chance of briefly seeing a light rain
shower. Look for stronger rain potential to drift coastward
tonight into Thursday before things clear out Thursday night.
Beyond that bit of fair weather, look for two more shots at rain.
One this weekend, in a window from Saturday night through Sunday
night. If moisture remains high, another disturbance will bring a
second shot at rain closer to mid-week.
SHORT TERM [Through Thursday]...
Cooler temperatures and periods of rain can be expected across
Southeast Texas today through Thursday. Will continue to carry
the higher rain chances up north and the lower rain chances at
the coast today, then increase the chances across the area for
tonight through Thursday morning. Similar to yesterday, there
remains the possibility for some locally heavy rain to develop
for parts of our northern counties where any training of cells
happens. Rain coverage will decrease (generally from north to
south) on Thursday as strong high pressure settles in from the
north. North winds will be strengthening during the day and we
might get close to wind advisory levels near/along some of our
coastal counties during the day on Thursday.
LONG TERM [Thursday Night Through Wednesday]...
By Thursday evening, we`re still looking for waves of vort blobs
making their way though the upper atmosphere above the remnant
frontal zone above the surface drifting slowly coastward. Guidance
continues to suggest that it will drift south enough to push the
best convergence for light to moderate rain showers offshore,
letting land areas dry out Thursday night. Expect the waters to
follow shortly thereafter as deeper dry air forces its way in, and
northwest flow aloft finally sets up due to ridging to our west.
This should give us a good shot at fair weather on Friday into
Saturday, though temperatures will likely be cooler than typical
for mid-to-late February. However, that is not likely to persist
deep into the weekend, as onshore winds are expected to return
Saturday.
An upper trough looks to head due east from the Desert Southwest
into the Southern Plains, inducing lee cyclogenesis around the
Panhandles on Sunday. This should give us a moisture and lift
connection with the Pacific at high altitudes again, while
boundary layer moisture returns with the onshore flow. So...you
probably guessed it...this turn of events should give us more
seasonable temperatures, but also a return of rain chances. I keep
some potential for showers in place as early as Saturday evening,
but guidance seems to be slowly coming into shape on the best
chances coming late Sunday afternoon into Sunday evening. The Euro
still comes through strong with a late weekend front - the GFS is
beginning to come around to that as well, but is still much
slower. For now, will continue to keep the forecast more Euro-ish
and going dry on Monday, but I do keep the PoP window spread wider
than I expect it will end up being due to uncertainty in timing
at this range.
Beyond that...well...good luck in determining a cohesive
narrative. There`s broad consensus in another stronger northern
stream trough moving through the Central US in the midweek, but
there`s precious little agreement on the strength of that trough,
or precise timing. Both will have significant implications for
weather in our area. We could see another front like at the
beginning of the week, complete with rain chances. Or, we may see
something more like a reinforcing front pushed by a mass of
colder, drier air. For now...I`m basically going with a blended
forecast of least regret, with modest temperature changes and
20-30 percent PoPs. As confidence grows (hopefully!) in a more
specific scenario, expect the forecast to trend in the direction
that confidence brings us.
MARINE...
A cold front will continue to slowly move across the coastal
waters today. Decreasing fog coverage can be expected behind
the front. As strong high pressure builds into the area from
the north, look for strengthening north winds beginning late
tonight or early on Thursday. Caution flags will likely be
needed for the increase in winds and building seas. Stronger
north winds and rough seas can be expected late Thursday
afternoon through early Friday morning with gale force wind
gusts possible. Seas will come down and winds will diminish/
return to the southeast on Saturday. The next cold front is
expected late Sunday night or early Monday morning.
FIRE WEATHER...
Despite the cold front already having crossed the area, unsettled
weather with high rain chances will persist through today and into
tomorrow before finally coming to an end. Similarly, the typical
post-frontal increase in winds should also be delayed, but still
looks to come Thursday afternoon/evening, while lingering rain
showers may still be in the picture, and conditions will be
further mitigated by previous rainfall and cooler weather
mitigating a drop in moisture, keeping relative humidity high.
Warmer temperatures on Friday should allow for lower humidity
values that afternoon. but mitigating factors are still present,
as all but fine fuels are likely to be fairly moist and winds will
also be weaker. The expected decrease in humidity and moderate wind
speeds may be favorable for prescribed burning, but that
determination - as always - will ultimately depend on multiple
factors beyond merely weather.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 46 50 37 53 37 / 80 80 10 0 0
Houston (IAH) 49 52 39 53 38 / 80 80 20 0 0
Galveston (GLS) 53 58 44 54 48 / 80 80 20 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Gale Watch from Thursday afternoon through late Thursday night
for the following zones: Coastal waters from Freeport to
Matagorda Ship Channel TX out 20 NM...Coastal waters from
High Island to Freeport TX out 20 NM...Waters from Freeport
to Matagorda Ship Channel TX from 20 to 60 NM...Waters from
High Island to Freeport TX from 20 to 60 NM.
&&
$$
DISCUSSION...Luchs
SHORT TERM...42
LONG TERM...Luchs
AVIATION...Fowler
MARINE...42
FIRE WEATHER...Luchs
FXUS64 KHGX 191806
AFDHGX
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1206 PM CST Wed Feb 19 2020
.AVIATION [18Z TAF Issuance]...
Expect scattered showers and IFR CIGs to continue through tomorrow
morning across the area. Through the rest of the day today, the
heaviest rain showers will remain north of the area along a
boundary. This boundary will move through late tonight bringing a
better chance of precipitation, but it will be weakening as it
pushes through. So, the sites that have the best chance of
getting SHRA will be CLL, UTS, CXO, and IAH. Overnight tonight
CIGs will remain around 5000 to 7000 feet, but ceilings do rise
tomorrow afternoon to MVFR as the front moves off the coast.
Breezy northerly winds will be expected starting tomorrow
afternoon through tomorrow night.
&&
.PREV DISCUSSION /Issued 547 AM CST Wed Feb 19 2020/...
DISCUSSION...
The front has finally passed through all of Southeast Texas and
has pushed out over the Gulf, finally bringing an end to the fog
event for the entire area, with the exception of some Gulf waters
several miles offshore.
Despite this, look for rainy conditions to continue. Like
yesterday, expect the most rain north of Houston - perhaps from
roughly Brenham to Livingston northward. For the rest of the area
south of that line, another cloudy day with sprinkles and mist are
likely, along with some chance of briefly seeing a light rain
shower. Look for stronger rain potential to drift coastward
tonight into Thursday before things clear out Thursday night.
Beyond that bit of fair weather, look for two more shots at rain.
One this weekend, in a window from Saturday night through Sunday
night. If moisture remains high, another disturbance will bring a
second shot at rain closer to mid-week.
SHORT TERM [Through Thursday]...
Cooler temperatures and periods of rain can be expected across
Southeast Texas today through Thursday. Will continue to carry
the higher rain chances up north and the lower rain chances at
the coast today, then increase the chances across the area for
tonight through Thursday morning. Similar to yesterday, there
remains the possibility for some locally heavy rain to develop
for parts of our northern counties where any training of cells
happens. Rain coverage will decrease (generally from north to
south) on Thursday as strong high pressure settles in from the
north. North winds will be strengthening during the day and we
might get close to wind advisory levels near/along some of our
coastal counties during the day on Thursday.
LONG TERM [Thursday Night Through Wednesday]...
By Thursday evening, we`re still looking for waves of vort blobs
making their way though the upper atmosphere above the remnant
frontal zone above the surface drifting slowly coastward. Guidance
continues to suggest that it will drift south enough to push the
best convergence for light to moderate rain showers offshore,
letting land areas dry out Thursday night. Expect the waters to
follow shortly thereafter as deeper dry air forces its way in, and
northwest flow aloft finally sets up due to ridging to our west.
This should give us a good shot at fair weather on Friday into
Saturday, though temperatures will likely be cooler than typical
for mid-to-late February. However, that is not likely to persist
deep into the weekend, as onshore winds are expected to return
Saturday.
An upper trough looks to head due east from the Desert Southwest
into the Southern Plains, inducing lee cyclogenesis around the
Panhandles on Sunday. This should give us a moisture and lift
connection with the Pacific at high altitudes again, while
boundary layer moisture returns with the onshore flow. So...you
probably guessed it...this turn of events should give us more
seasonable temperatures, but also a return of rain chances. I keep
some potential for showers in place as early as Saturday evening,
but guidance seems to be slowly coming into shape on the best
chances coming late Sunday afternoon into Sunday evening. The Euro
still comes through strong with a late weekend front - the GFS is
beginning to come around to that as well, but is still much
slower. For now, will continue to keep the forecast more Euro-ish
and going dry on Monday, but I do keep the PoP window spread wider
than I expect it will end up being due to uncertainty in timing
at this range.
Beyond that...well...good luck in determining a cohesive
narrative. There`s broad consensus in another stronger northern
stream trough moving through the Central US in the midweek, but
there`s precious little agreement on the strength of that trough,
or precise timing. Both will have significant implications for
weather in our area. We could see another front like at the
beginning of the week, complete with rain chances. Or, we may see
something more like a reinforcing front pushed by a mass of
colder, drier air. For now...I`m basically going with a blended
forecast of least regret, with modest temperature changes and
20-30 percent PoPs. As confidence grows (hopefully!) in a more
specific scenario, expect the forecast to trend in the direction
that confidence brings us.
MARINE...
A cold front will continue to slowly move across the coastal
waters today. Decreasing fog coverage can be expected behind
the front. As strong high pressure builds into the area from
the north, look for strengthening north winds beginning late
tonight or early on Thursday. Caution flags will likely be
needed for the increase in winds and building seas. Stronger
north winds and rough seas can be expected late Thursday
afternoon through early Friday morning with gale force wind
gusts possible. Seas will come down and winds will diminish/
return to the southeast on Saturday. The next cold front is
expected late Sunday night or early Monday morning.
FIRE WEATHER...
Despite the cold front already having crossed the area, unsettled
weather with high rain chances will persist through today and into
tomorrow before finally coming to an end. Similarly, the typical
post-frontal increase in winds should also be delayed, but still
looks to come Thursday afternoon/evening, while lingering rain
showers may still be in the picture, and conditions will be
further mitigated by previous rainfall and cooler weather
mitigating a drop in moisture, keeping relative humidity high.
Warmer temperatures on Friday should allow for lower humidity
values that afternoon. but mitigating factors are still present,
as all but fine fuels are likely to be fairly moist and winds will
also be weaker. The expected decrease in humidity and moderate wind
speeds may be favorable for prescribed burning, but that
determination - as always - will ultimately depend on multiple
factors beyond merely weather.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 46 50 37 53 37 / 80 80 10 0 0
Houston (IAH) 49 52 39 53 38 / 80 80 20 0 0
Galveston (GLS) 53 58 44 54 48 / 80 80 20 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Gale Watch from Thursday afternoon through late Thursday night
for the following zones: Coastal waters from Freeport to
Matagorda Ship Channel TX out 20 NM...Coastal waters from
High Island to Freeport TX out 20 NM...Waters from Freeport
to Matagorda Ship Channel TX from 20 to 60 NM...Waters from
High Island to Freeport TX from 20 to 60 NM.
&&
$$
DISCUSSION...Luchs
SHORT TERM...42
LONG TERM...Luchs
AVIATION...Fowler
MARINE...42
FIRE WEATHER...Luchs