FEBRUARY 2019: Cold Front & Storm Chances

[srainhoutx]

Sleet reported in South Austin

[srainhoutx]

Brief snow flakes reported near Lake Bryan (Brazos County)

[srainhoutx]

Light graupel reported in Del Rio

[srainhoutx]

Sleet/graupel mix reported in Kerrville

[srainhoutx]

Sleet reported in Boerne

[srainhoutx]

Small hail reported in Del Rio. There is a convective nature with the shortwave approaching S Central and E/NE Texas today.

[srainhoutx]

Wintry mix reported in Madison County

[CRASHWX]

Looks like FV3 got it right

[Cpv17]

Boy it is freaking cold outside. Massive difference from 24 hours ago. Talking a good 30-40 degree difference. Crazy!!

[srainhoutx]

Temperatures continue to slowly fall and Huntsville has dropped to 31F. My forecast low was 38F and we have dropped to 36F now. I suppose it's not out of the question that isolated wintry mix could fall across portions of Austin, Waller, NW Harris and Montgomery Counties if we moisten up a bit with the radar echos advancing ENE from our SW around Victoria.

[tireman4]

000
FXUS64 KHGX 081035
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
435 AM CST Fri Feb 8 2019

.DISCUSSION...
Temperatures will fall to near freezing across northern parts of
the CWA in the next 4 hours or so, but then climb above 32 in
mid/late morning hours. Cloudy skies will keep high temperatures
from making it much above 38-45 for much of the area today.

An elongated H5 ridge extending from the Yucatan across Florida
and into the Atlantic will maintain a sw flow aloft locally...tapping
into a long fetch of Pacific moisture that`ll be streaming
overhead for several days.

Impulses embedded in that flow are currently producing returns on
radar, but very dry air under the 12000-15000ft cloud base is
keeping this from reaching the ground in se Tx at this time. That
being said, we do expect additional moistening down to about
9000ft later today so we should see some iso/sct pockets of precip
possibly making it to the surface as the day progresses (better
chances far north). Upper level temp profile across northern
parts of the area are such that some light sleet pellets could be
mixed in, but melt upon impact to the ground. At this time,
very little if any impacts are expected considering sfc temps
should be above freezing when the better chances arrives. Atmospheric
profile becomes less favorable (warms) for any mixed precip after
midnight across this portion of the state.

Llvl winds will gradually veer around to the east then southeast
over the weekend allowing Gulf moisture to filter back into the
area. Warm front moves inland Sunday and Sunday night bringing
much warmer conditions along with the associated dz/-ra/fog that
usually goes with it. Fcst soundings become increasingly saturated
so look for rain chances to increase into Monday - though with a lack
of a focusing mechanism for any significant wx.

The next cold front it penciled in for Monday night and Tuesday
morning. Expect a band of showers and maybe a few embedded tstms
along the front. There is some uncertainty whether rain ends w/
fropa, or overrunning precip continues into early Wed like ECMWF
is suggesting. 47

&&

.MARINE...
Elevated winds/seas continuing across the bays/coastal waters this
morning. Will maintain the Gale Warning across the offshore waters
and a Small Craft Advisory for the bays/nearshore waters until mid
morning. Winds over the bays should decrease further during the af-
ternoon...but is expected to remain strong over the coastal waters
until tonight. Offshore winds to fall below SCA/SCEC criteria late
Sat night as the direction becomes more easterly. Onshore winds to
return by Sun ahead of the next cold front which is currently fore-
cast to move into the Gulf early Tues. SCEC/SCA flags will be poss-
ible in the wake of this boundary. 41

&&

.AVIATION...
Keeping a close eye out west as the activity there moves toward SE
TX through the morning hours. The mention of wintry weather may be
needed for some of our northern sites by this afternoon. Otherwise,
moderate/strong north winds and mid/high clouds will prevail. 41

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 39 33 42 39 59 / 40 30 30 40 50
Houston (IAH) 43 36 45 43 66 / 10 10 20 10 30
Galveston (GLS) 47 40 52 51 65 / 10 10 20 10 10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until 9 AM CST this morning for the following
zones: Brazoria Islands...Galveston Island and Bolivar
Peninsula...Matagorda Islands.

GM...Small Craft Advisory until 9 AM CST this morning for the
following zones: Galveston Bay...Matagorda Bay.

SMALL CRAFT SHOULD EXERCISE CAUTION from 9 AM this morning to
noon CST today for the following zones: Galveston Bay...
Matagorda Bay.

Small Craft Advisory until noon CST today 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.

Gale Warning until noon CST today for the following zones:
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.

&&

$$

[Kludge]

Looks like FV3 got it right

… and JB, it seems.

[DoctorMu]

Brief snow flakes reported near Lake Bryan (Brazos County)

lol Wintry stuff from the Hill Country to the Louisiana border! Disturbance/impulses hit that narrow window as we hover near freezing. Looks like College Station is just south of a SW to NE run. A lot of what is on the radar is probably verga (DP = 25°F), but we'll count this close as a cigar in SE Texas.

[DoctorMu]

Looks like FV3 got it right

Nailed it.

[DoctorMu]

Boy it is freaking cold outside. Massive difference from 24 hours ago. Talking a good 30-40 degree difference. Crazy!!

Try nearly 50°F

[srainhoutx]

Friday morning weather briefing from Jeff:

Slight chances for a mixture of light rain/light sleet/snow flurries this afternoon and evening northwest of a line from Brenham to Huntsville.

A cold arctic air mass has moved into the region with current temperatures of 30-32 from Huntsville to Bryan and low 40’s to mid 30’s across the rest of the region. N winds of 10-20mph are helping to produce wind chills in the low 20’s over much of the area…a big contrast to the 70’s of yesterday morning.

In addition to the cold temperatures, a weak short wave is moving across MX and toward TX and resulting in widespread precipitation development in the cloud bearing level of the atmosphere from near Del Rio NE across much of central TX into east TX. Below this cloud deck level the air mass is very dry with surface temperature/dewpoints spreads of 10-15 degrees over the region leading to surface RH of only around 55-65%. Much of what is seen on radar in the cloud level is evaporating on the way to the surface. Few of the observation sites are reporting any precipitation. However Austin has reported a sleet/graupel (snow pellet) mix this morning and social media images support this observation, so in a few very localized locations some mixed precipitation is reaching the ground.

Air mass will attempt to saturated from the top down toward the surface today into tonight with cloud bases lowering, but it remains in question as to just how much of the dry air can be overcome allowing any precipitation to reach the ground. Think the best chances for this will be way up north over our area (College Station to Huntsville), but more likely north of an Austin to Centerville line. Anything that falls will be light as most is going to evaporate in the dry sub cloud layer.

With surface temperatures warming 2-4 degrees today, would expect the entire area to be above freezing by late morning and if anything were to reach the ground, warm ground temperatures from the 80’s on Wednesday would result in immediate melting….so no impacts. Travel to the NW of our area toward Dallas or NC TX should be monitored as this is where slightly heavier precipitation rates and colder surface temperatures will be found which may result in some roadway impacts.

Warm air advection begins late tonight above the surface and expect our local temperatures to only fall a few degrees tonight. Area remains cold on Saturday with arctic surface high locked in place and the formation of a coastal trough which will start to pump moisture over the top of the eroding surface air mass. Cloud decks will lower and scattered light rainfall will develop from the SW over the weekend as a warm front advances northward. Could see fog, drizzle, and light rain on Sunday as the warm front nudges into the area from the SSW and temperatures warm well into the 60’s under increasing onshore flow.

We will be back in the warm sector air mass by Sunday night and sea fog will once again be possible along the coast and spreading inland along with a continued slight chances of rain as disturbances ride up from the SW and across the region. Next front should come across the area late Monday into Tuesday returning winter for a day or two. It remains in question if this front can clear the area out with the ECMWF indicating another coastal trough and overrunning event in the post frontal air mass…which would mean clouds and rain linger into the middle of next week.

Overall pattern continues to look active for the next 2 weeks with clouds and chances for rain in much of the forecast and seasonal February temperatures.

[Cpv17]

Boy it is freaking cold outside. Massive difference from 24 hours ago. Talking a good 30-40 degree difference. Crazy!!

Try nearly 50°F

Maybe where you are lol not here though. Went from low 70’s here to upper 30’s. 35 degrees.

[CRASHWX]

Looks like FV3 got it right

… and JB, it seems.

Yes JB is on it this morning...he dropped the chicken bones and got it right! Lol

[AggiedadLA]

Lightning showing up just north of Schulenburg.

[tireman4]

rea Forecast Discussion
National Weather Service Houston/Galveston TX
1038 AM CST Fri Feb 8 2019

.UPDATE...

Numerous reports, photos, and videos of a mix of wintry precip
types from Brenham to College Station to Madisonville (and more!)
this morning. Very dry air has been successful at evaporating most
of the precipitation that has fallen, but this has also cleared
the way for a small handful of sleet pellets and graupel (the
Dippin` Dots of winter) to reach the ground for municipalities far
north of the Houston metro.

Look for these patches of very light precipitation to continue
into the early afternoon, though we may warm just enough late this
afternoon to put a brief stop to any frozen precipitation.
Intensity and/or the number of patches may pick up just a bit as
moisture aloft increases some and cloud bases sink a few thousand
feet, but the general character should stay the same.

Temperatures aloft look to increase through the night, but as long
as the wet bulb profile stays at or below freezing, I`m going to
hang onto the chance for a mix of precip. Because of that, have
dragged the potential for IP (be it sleet or graupel) past
midnight and until dawn. This may need to go out further, but have
largely been holding to the HRRR timeframe, as it appears to be
handling the temp structure best so far this morning.

&&