559 
FXUS64 KBRO 110056 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
756 PM CDT Tue Mar 10 2020

.DISCUSSION...Updated for latest aviation discussion below.

&&

.AVIATION...Satellite shows copious mid and upper cloud cover 
moving from west to east through a mid level ridge building over 
the area. An inversion at 5 kft with close to saturated conditions
underneath is supportive of lower decks and at times MVFR 
conditions. The NAM is more aggressive in taking ceilings down to
MVFR Wednesday morning, but both the NAM and GFS increase winds 
to moderate by late morning to early afternoon, and improve 
any degraded conditions to VFR.

&&

.PREV DISCUSSION... /issued 253 PM CDT Tue Mar 10 2020/ 

SHORT TERM (Now through Wednesday night): Record PWAT of 1.77 
inches was observed with the 12Z sounding this morning. As 
previously advertised, deep column moisture and instability 
rounding the mid-level ridge across Deep South Texas have 
resulted in persistent light rain showers this morning into this 
afternoon. Radar activity has steadily diminished over the past 
hour or two. Have kept POPs generally under 25 percent through 
this evening. A few CAMs are holding onto a convective chance 
across the northern ranchlands before PVA generally exits offshore
early tonight. 

Patchy fog across the lower Texas coast may reach a bit further 
inland tonight with abundant low level moisture and diminishing 
winds. Model guidance is lending some confidence in fog both tonight 
and tomorrow night, especially along the coast. Less cloud cover on 
Wednesday should yield much warmer temperatures, especially out 
west, with near 90 degrees on tap across portions of the upper 
valley and the lower valley warming into the 80s. 

LONG TERM (Thursday through Tuesday): Broad 500mb ridging of high
pressure across Deep South Texas will maintain an above-normal
temperature trend, along with mainly rain-free conditions into 
the weekend. A deep upper-level low will unravel into an open wave
as it progresses eastward into the Desert Southwest by Friday 
night. Meanwhile, a 590dam high will strengthen across the Central
Gulf. This will back winds aloft to the southwest across the
region while allowing moisture to increase. Despite precipitable
water values approaching record values on Saturday, weak flow
aloft may not provide much support for organized convective
development. Models do continue to show slight chances of
precipitation in the western areas of Deep South Texas, mainly
west of Interstate 69 C for the weekend. Any rainfall should
remain light, though, resulting in worsening drought conditions.
No cold fronts are expected through the forecast period with
moderate southeast winds expected each day. This, combining with
increasing mid-level heights, will allow temperatures to be well
above normal. Many locations may reach the lower to mid 90s into
early next week.

MARINE (Now through Wednesday night): Light to moderate 
southeasterly flow continues through the short term as surface high 
pressure edges further east across the Gulf of Mexico. East to 
southeasterly swell has maintained elevated seas offshore just under 
6 feet most of the morning and early afternoon. Marine conditions 
should slowly improve into Wednesday night. Patchy fog has returned 
across nearshore and coastal waters, due to much warmer air and 
abundant moisture above the cooler surface temperatures, and may 
remain pesky over the next couple of days, building more onshore 
overnight and gradually retreating through the morning.

Thursday through Tuesday: Moderate southeast winds can be expected
as surface high pressure remains over the Northeast Gulf of
Mexico. This will keep seas fairly elevated through much of the
long term. Advisories are not anticipated, however, small craft
may need to exercise caution, especially beyond 20 nautical miles
off the coast. A few showers will be possible this weekend, though
any activity should be isolated and light.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

$$

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