Alert archive / Texas / Red Flag Warnings in 2018

Red Flag Warning 2, NWS Brownsville, TX

March 11, 2018Hidalgo County, Starr County, Texas

NWS Brownsville, TX issued this red flag warning at Mar 11, 2018, 3:51 PM CDT for Hidalgo County, Starr County, Texas. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 11, 2018, 3:51 PM CDT (20:51 UTC)
Expired
Mar 11, 2018, 7:00 PM CDT
In force
3 hr
Issued by
NWS Brownsville, TX

Counties Hidalgo County, TX, Starr County, TX

The radar

The Brownsville radar (KBRO), 121 km from the middle of the area, began a volume at 20:50 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Brownsville Intl, TX (KBRO), launched 12:00Z, 8.9 hours before the alert went out and 124 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brownsville Intl, TX at 12:00Z on 2018-03-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 387 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brownsville Intl, TX at 12:00Z on 2018-03-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
387 J/kg
Mixed-layer CIN
-394 J/kg
Mixed-layer LCL
885 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

705 
WWUS84 KBRO 112051
RFWBRO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Brownsville TX
351 PM CDT Sun Mar 11 2018

...Very low humidity and gusty winds creating erratic wildfire
behavior potential through late afternoon...

.A dry front has passed the upper Rio Grande Valley with a sharp
wind shift and heat spike that will bring a short period of strong
northwest winds and humidity to 15 percent or lower late this
afternoon. Rapid spread of wildfires is expected during this time.

TXZ252-253-120000-
/O.NEW.KBRO.FW.W.0002.180311T2051Z-180312T0000Z/
Starr-Hidalgo-
351 PM CDT Sun Mar 11 2018

...RED FLAG WARNING IN EFFECT UNTIL 7 PM CDT THIS EVENING FOR
STRONG WINDS AND HUMIDITY AT OR BELOW 15 PERCENT FOR FIRE WEATHER
ZONES 252 AND 253...

The National Weather Service in Brownsville has issued a Red Flag
Warning, which is in effect until 7 PM CDT this evening. 

* AFFECTED AREA...Fire weather zones 252 and 253.

* WIND...FROM THE NORTH AT 20 TO 25 MPH WITH GUSTS TO 30 OR 35 MPH
  THROUGH 6 PM WITH SOME DIMINISHING BETWEEN 6 AND 7 PM.
  
* HUMIDITY...FALLING TO 12 TO 17 PERCENT BETWEEN 4 AND 6 PM WITH
  SOME INCREASE TO 25 PERCENT BY 7 PM.

* THUNDERSTORMS...NONE.

* HIGHEST THREAT...is located along and just north of the Rio
  Grande in Starr and Hidalgo County where temperatures will reach
  the mid to upper 90s and humidity fall to 15 percent or lower.

* IMPACTS...any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means critical fire weather conditions are
occurring now...or will shortly. In general...these conditions
include sustained 20 foot winds of 25 MPH or greater...humidity
ranging from below 25 percent in Zapata County to below
45 percent along the coast...each lasting for 2 hours or longer...
and cured fuels. Humidity below 25 percent in most areas will
trigger fire danger at lower wind speeds. Detailed decision
tables are found at HTTP://WEATHER.GOV/RGV/?N=MAPCOLORS#FIRE.

&&

$$

52/BSG
1 follow-up statement
840 
WWUS84 KBRO 120015
RFWBRO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Brownsville TX
715 PM CDT Sun Mar 11 2018

...Temperatures Falling and Humidity Increasing This Evening as
Winds Slowly Diminish...

.After a two to three hour period of hot temperatures, gusty 
north winds, and humidity near 15 percent, conditions are steadily
improving this evening. While north winds will remain gusty
through mid evening, temperatures falling through the 70s and
humidity rising above 50 percent will gradually reduce the threat
for rapid spread of any wildfires that develop.

TXZ252-253-120115-
/O.EXP.KBRO.FW.W.0002.000000T0000Z-180312T0000Z/
Starr-Hidalgo-
715 PM CDT Sun Mar 11 2018

...RED FLAG WARNING HAS EXPIRED FOR STRONG NORTH WINDS 20 TO 25
MPH AND GUSTY COMBINED WITH HUMIDITY NEAR 15 PERCENT AND HOT 
TEMPERATURES FOR FIRE WEATHER ZONES 252 AND 253...

As of 7 PM, temperatures had fallen into the 70s to lower 80s,
humidity had risen to between 30 and 50 percent, and north winds
were diminishing to 20 mph or less with a few higher gusts across
southern Hidalgo and Starr County. By mid evening, winds will
still be gusting to 20 to 25 mph in spots, but temperatures will
be in the upper 60s to lower 70s and humidity between 45 and 55
percent, well above the threshold for rapid wildfire growth and
spread.

Residents are still advised to use caution with any outdoor
activities this evening, such as grilling, and continue to do
these on paved or dirt areas away from high grass and brush.

$$

52/BSG

The office that day

Everything else NWS Brownsville, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 11, 4:06 AM CDTSmall Craft AdvisoryBRO36 hr
Mar 11, 4:06 AM CDTSmall Craft Advisory for WindsBRO32 hr
Mar 11, 9:38 AM CDTRip Current StatementBROKenedy33 hr

Nearby

Red Flag Warnings in Texas, 2018Every red flag warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.