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Area forecast discussion 
National Weather Service San Angelo Texas
400 PM CDT Monday Sep 1 2014

Short term...
(tonight and tuesday)

No significant changes made to the short term. We will continue to
see hot and muggy conditions. Heat index values across the area were
around 100 degrees between 2 and 3 this afternoon with a Hot Spot of
106 at Weinert. Very little change in the overall pattern will take
place between today and tomorrow. A sprawling upper level ridge will
remain in place across the southern half of the conus, with a strong
thermal ridge in the low levels across West Texas and eastern New
Mexico. So, will go with a persistence forecast for the most part.
Expect highs again from the mid 90s along the I-10 corridor to the
102 degree range north of I-20 where the thermal ridge will be
strongest for our area. Overnight, lows should fall into the lower
to upper 70s. Many locations this morning only got down to around 75
or 76 degrees, and with very warm afternoon highs again today, warm
overnight lows should also persist. With the upper level ridge in
control, the dry forecast will continue.

20

Long term...
(tuesday night through next monday)

The upper high will become centered over Arkansas on Wednesday, and
over northern Mississippi on Thursday. As this occurs, a deeper
southeasterly flow will develop over much of Texas. The 12z models
bring a weak disturbance or two up the Rio Grande Valley during that
time. This would be to the north of the tropical system currently
referenced by the National Hurricane Center. With the associated
moisture increase, precipitable water values are progged to
increase into the 1.5 to 1.7 inch range across our southern
counties Wednesday into Thursday. This scenario may enable a
possibility for isolated to scattered showers and thunderstorms to
occur in the southern part of our area. Would like to see another
consistent model run, however, before adding mentionable pops.

Some weakening of the 850mb thermal ridge is indicated for the
middle to late part of the week. With a bit of increased daytime
cloud cover, expect highs to ease back a few degrees across our
area.

The forecast is somewhat problematic for next weekend. The 12z GFS
and European model (ecmwf) shift the center of the upper high back to the west over
Texas. With an upper trough moving across parts of southern Canada,
both models bring the trailing portion of associated cold front
south into Texas next Saturday. Indications are for the front to
probably stall somewhere over our area, and both models have quantitative precipitation forecast
with the front. Surface high north of the front is progged to be
fairly strong for this time of year (over 1020mb), and could have
the effective front being driven south by convection. Have quite
a bit of uncertainty at this point on the details, however. Appears
that our northern counties would have the better chance of being
affected by the front and associated convection. Carrying slight
chance pops for that area Saturday night into Sunday night.

19

&&

Preliminary point temps/pops...
Abilene 75 99 74 96 73 / 0 5 5 5 5
San Angelo 76 99 74 95 73 / 0 5 5 10 10
Junction 74 95 73 92 73 / 0 5 5 10 10

&&

Sjt watches/warnings/advisories...
none.
&&

$$

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