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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1059 PM CST Friday Feb 5 2016

Aviation...
watching a cold front approach the area from the northwest. The
front should be through drt by the start of the period and Austin
and San Antonio by 08 or 09z. The biggest change will be a wind
shift to the west or northwest with frontal passage. There is a
slight chance for rain in Austin and San Antonio...but any rain
will be very light and not affect flying category. Winds will
increase to 10 to 15 kts with gusts up to 25 kts Saturday morning
and continue through the afternoon. Clear and light north winds
after sunset Saturday.

&&

Previous discussion... /issued 1005 PM CST Friday Feb 5 2016/

Update...cold front was approaching the County Warning Area from the north...
near a Brownwood to Sonora line at 10 PM. Base of middle and upper
level trough will swing quickly through the County Warning Area overnight...with
height falls and DPVA assisting in the development of showers
across the eastern Hill Country southward into the I-35 corridor
midnight through 2 am...then racing through the remainder of the
County Warning Area east of I-35 2-5am. The showers will be primarily located
northeast of a Llano to San Marcos to Cuero line. Rap analysis
indicates -24 to -27 degree c 500mb temperatures in the base of the trough
entering the ewx County Warning Area. Forecast soundings show a sliver of elevated
instability...when combined with moderate dynamical forcing...
sufficient enough to possibly support an isolated thunderstorm or
two across the northeast County Warning Area. The window will be short and chances
low...nevertheless elected to include a slight mention of thunder
in northeast zones.

Rapid clearing will take place early in the morning. Breezy
conditions developing middle morning through early afternoon...with
some gusts 25-30 kts possible across the eastern Hill Country and
I-35 corridor...before settling back down middle to late afternoon as
relative humidity values bottom out. An elevated fire weather danger has been
highlighted in the severe weather potential statement.

Previous discussion... /issued 240 PM CST Friday Feb 5 2016/

Short term (tonight through Saturday night)...
mostly clear skies with just a few cirrus clouds continue to
prevail across the area at the present time. Dry air still exists
at the surface with dewpoints remaining in the 20s and 30s. With
south winds returning we should see moisture values creep up ever
so slightly across the eastern half of the area with dew points
near 40 degrees by the overnight hours. This will help with the
production of a thin line of showers which should begin to develop
around midnight across the northern Hill Country. Currently...a
strong trough can be seen on water vapor imagery digging into
eastern New Mexico. At the same time...the responding cold front
is currently in West Texas. The progression of the upper trough
has slowed a bit and this should allow there to be better upper
support for shower production along the frontal boundary
overnight. Yesterday...models showed the main lift associated with
the upper trough to be ahead of the front with little to no shower
production along the surface boundary. With the two features being
somewhat better aligned and with slightly higher low-level
moisture...high-res models are showing a thin line of showers
moving through the eastern half of the County Warning Area along the front
overnight before exiting the area across the east just after
sunrise. Rainfall amounts from this activity will range from a
trace to about a tenth of an inch. Should see some clearing behind
the front tomorrow afternoon with highs topping out in the lower
to upper 60s for much of the area with breezy northerly winds.
Should see many areas reach the freezing mark Sunday morning once
again behind the front.

Long term (sunday through friday)...
the long-term forecast will continue to see dry weather with
another front moving through the area Sunday night. This front
will be dry as the best upper dynamics remain to the northeast of
the region. This front will bring with it drier air with dewpoints
around 10 degrees possible across the western counties by Monday
morning. With the drier air and weaker winds on Tuesday
morning...should see areas get to freezing once again. Went a
couple of degrees below guidance for Tuesday morning given how dry
the air will be. Temperatures will warm by Wednesday and Thursday
as south flow returns...but another dry front is possible by
Friday.

Fire weather...
with continued dry air in place across the area...afternoon
humidity values will be quite low. Values for the most part will
range from the middle-teens to 30 percent Saturday through Thursday.
The lower values will occur across the western counties with the
higher values across the east. With the low values across the
west...the wind forecast will be heavily monitored for possible
elevated to critical fire weather conditions each day. Tomorrow
behind the cold front...northerly winds are expected to be
lowering to 10 to 12 miles per hour once the 20 degree or less relative humidity values
occur. Given this elevated fire weather conditions are expected
for the western locations and possible the northwestern Hill
Country...or areas mainly west of Highway 83.

Elevated fire weather conditions should remain confined to the
northern Hill Country on Sunday where winds will be strongest and
then be area wide on Monday as breezy winds behind a cold front
create near critical fire weather conditions with even drier air
expected.

&&

Preliminary point temps/pops...
Austin Camp Mabry 39 61 36 68 39 / 50 - 0 0 0
Austin Bergstrom international Airport 37 62 31 67 37 / 50 - 0 0 0
New Braunfels Muni Airport 38 64 33 68 37 / 40 - 0 0 0
Burnet Muni Airport 33 59 33 67 36 / 30 0 0 0 0
del Rio International Airport 36 67 35 71 39 / 0 0 0 0 0
Georgetown Muni Airport 36 59 32 66 37 / 40 - 0 0 0
Hondo Muni Airport 36 66 31 70 37 / 30 0 0 0 0
San Marcos Muni Airport 39 63 33 66 37 / 50 - 0 0 0
La Grange - Fayette regional 41 62 35 66 39 / 50 20 0 0 0
San Antonio International Airport 40 65 34 68 38 / 30 - 0 0 0
Stinson Muni Airport 40 66 34 69 39 / 30 - 0 0 0

&&

Ewx watches/warnings/advisories...
none.
&&

$$

Mesoscale/aviation...05
synoptic/grids...runyen
public service/data collection...33

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