Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Houston/Galveston Texas
622 PM CDT sun may 24 2015
clouds are in the process of moving eastward and out of the area. Could
see some MVFR ceiling and possible fog development at some of the sites
overnight. Going with vcsh for possible middle morning shower development...
then thunderstorms and rain for the afternoon hours as the next batch of rain showers/thunderstorms and rain develops
and move across the area. Things quiet down tomorrow evening as activity
comes to an end. 42
Previous discussion... /issued 344 PM CDT sun may 24 2015/
seeing some scattered thunderstorms and rain redevelop across north parts of the area where
heating and rrq of departing jet are working their magic.
Anticipate these to taper off shortly after sunset. In the
meantime...can still see some isolated strong storms/downpours that'll
need to be monitored.
Overnight system made much quicker eastward progress than expected
yesterday and is well into cntl la. (Faster nam12 actually did a
respectable job). Also see no lingering surface boundary along I-10
on current surface observations that some models were indicating for
tonight - serving as a focus for possible overnight convection as
onshore flow and low level jet feeds into it. Only Canadian and possibly later
Storm Prediction Center hrrr runs depict such a scenario now - the rest (including
ecmwf) keep the region mostly dry overnight. This gives US a bit
more confidence in a drier overnight period than earlier - but
still no guaranty. Have slightly lowered probability of precipitation in response.
Next impulse seen on west/v imagery in southern Nevada will move across
the state Monday. Expect this disturbance to trigger another shower and
thunderstorm complex to our west. This system should be moving
into western parts of the area toward middle morning and across the
remainder of the region through the afternoon hours. Issued
another Flash Flood Watch from middle morning into the evening Monday for
locations generally along and north of I-10. There is some uncertainty
regarding how fast the system will move out and some locations
might see precipitation continue into the evening. In general...expect
1 to 3 inch rainfall amounts in the watch area and less so further
south. Localized higher totals are possible where training cells
occur...and also if the event drags on into the evening hours.
This watch will need to be expanded in time if it does.
In addition to training storms...dynamics west/ this system also
look favorable for some strong/severe storms with wind damage and
tornadoes being the primary threat. Grounds are wet and trees are
more prone to be blown down with less intense winds than they
Spoke about the uncertainty about Monday night regarding timing of
the exit of precipitation. Will just need to watch trends. Remainder of
the work week would anticipate scattered (mainly afternoon/evng) precipitation each
day across inland areas. Another trough approaches the neighborhood
going into next weekend...along west/ higher probability of precipitation unfortunately. 47
looks like a reprise from widespread thunderstorms over the bays and
Gulf waters until at least later tonight and likely until Monday.
The pressure gradient looks to weaken a bit tonight...but then
tighten back up on Monday before weakening again Monday evening. For
the most part expect advisory conditions through Monday
afternoon...although the winds could diminish slightly below 21
knots tonight at least over the bays and nearshore waters.
Regarding The Tides...Galveston Channel and the North Jetty both
recorded tide levels of about reached about 1.2 feet above normal
levels during the time of the astronomical high tide earlier today.
Tide levels are expected to be slightly lower late tomorrow morning
during the high tide time. Even so...wave run up could still present
some problems with minor flooding on low lying areas along the Gulf
facing beaches of the Bolivar Peninsula from late morning to early
afternoon on Monday.
Preliminary point temps/pops...
College Station (cll) 73 84 71 87 74 / 50 90 70 30 20
Houston (iah) 74 84 72 87 74 / 30 80 60 40 20
Galveston (gls) 78 84 78 85 78 / 30 80 60 20 20
Texas...Flash Flood Watch from Monday morning through Monday evening for
the following zones: Austin...Brazos...Burleson...
High rip current risk through Monday evening for the following
GM...Small Craft Advisory until 7 PM CDT Monday for the following
zones: Galveston Bay...Matagorda Bay...waters from Freeport
to the Matagorda Ship Channel 20 nm to 60 nm...waters from
Freeport to the Matagorda Ship Channel out 20 nm...waters
from High Island to Freeport 20 to 60 nm...waters from High
Island to Freeport out 20 nm.