Alert archive / Texas / Winter Storm Watches in 2017

Winter Storm Watch 3, NWS Amarillo, TX

April 28, 201711 counties in Texas; Beaver County, Texas County, Oklahoma

NWS Amarillo, TX issued this winter storm watch at Apr 28, 2017, 4:20 AM CDT for 11 counties in Texas; Beaver County, Texas County, Oklahoma. It took effect at Apr 29, 2017, 7:00 AM CDT. It was in force for .

The area

The counties it named.

The facts

Issued
Apr 28, 2017, 4:20 AM CDT (09:20 UTC)
In effect from
Apr 29, 2017, 7:00 AM CDT
Expired
Apr 28, 2017, 10:08 PM CDT
In force
Issued by
NWS Amarillo, TX

Counties Beaver County, OK, Texas County, OK, Dallam County, TX, Deaf Smith County, TX, Hansford County, TX, Hartley County, TX, Hutchinson County, TX, Moore County, TX, Ochiltree County, TX, Oldham County, TX, Potter County, TX, Randall County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 76 km from the middle of the area, began a volume at 09:21 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

Amarillo Airport, TX (KAMA), launched 00:00Z, 9.3 hours before the alert went out and 77 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, Amarillo Airport, TX at 00:00Z on 2017-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 00:00Z on 2017-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3162 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this winter storm watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Amarillo, TX wrote its last area forecast discussion before this winter storm watch went out at Apr 28, 12:27 AM CDT, 3 hours 53 minutes earlier.

Area forecast discussion, Apr 28, 12:27 AM CDT, 3 hours 53 minutes before
Area Forecast Discussion
National Weather Service Amarillo TX
1227 AM CDT Fri Apr 28 2017

.AVIATION...
VFR conditions will start the 06Z TAF period. However as we
progress toward the end of the TAF period, MVFR conditions will
be likely at all TAF sites. West and southwest winds throughout
the day will transition into a more north and northeasterly flow
as we go past 00Z Saturday. Winds throughout the day will be
between 15-20 kts with gusts over 25 kts at times. This will be
reduced to 10-15 kts after 00Z Saturday. Our next weather system
will be moving east-southeast across all TAF sites with
precipitation starting at KDHT/KGUY around 00Z and KAMA between 03
and 06Z. Accompanying the precipitation, the most pronounced
aviation hazard will be the lower cigs between 3.5-4.5 kft just
out ahead of the precipitation timing. MVFR conditions are likely
from around 00Z Saturday through to the end of the TAF period for
all TAF sites.

Meccariello

&&

PREV DISCUSSION... /Issued 423 PM CDT Thu Apr 27 2017/

DISCUSSION...
A cold front will push across the Panhandles tonight before
stalling south of the forecast area. The frontal boundary is then
forecast to lift northward Friday and Friday night as a warm front
before a secondary surge of even much colder air drives the front
south again. Vigorous closed upper low will develop over the Great
Basin region Friday and then digs south and east near the Four
Corners region by late Friday and then into central and southeast
New Mexico Friday night and Saturday. The upper low is then
expected to lift northeast across the southern Texas Panhandle
Saturday night and Sunday. Convection will diminish this evening
and tonight before developing once again Friday afternoon and
Friday night. As 850 mb temps fall to at or below freezing in the
colder sector of the upper low Saturday and early Sunday, wintry
precipitation is expected to spread northwest to southeast across
much of the northwest half or two-thirds of the forecast area.

Some rain and snow mix or snow in the higher elevations of the
western Oklahoma Panhandle will be possible mainly late Friday
night into Saturday morning, however best chances are expected
Saturday night and early Sunday. Lots of uncertainties on timing
and track of the upper low resulting in low confidence on
snowfall accumulations and locations impacted. Feel best chances
will mainly be across the northern and western portions of the
Texas Panhandle as well as the western and possibly the central
Oklahoma Panhandle. Upper low lifts northeast across the central
Plains states by early next week as upper ridge builds across the
western states. Another northern stream shortwave trough will
track across the central Rockies by late Tuesday and approach the
Panhandles by next Wednesday. Chances for convection will increase
by the middle of next week with the approach of this upper trough
and as a backdoor cold front moves through the forecast area by
next Tuesday and Wednesday.

Schneider

&&

.AMA Watches/Warnings/Advisories...
TX...None.
OK...None.

&&

29/3
Hazardous weather outlook, Apr 27, 5:14 PM CDT, 11 hours 6 minutes before
Hazardous Weather Outlook...UPDATED
National Weather Service Amarillo TX
514 PM CDT Thu Apr 27 2017

OKZ001>003-TXZ001>020-281100-
Cimarron-Texas-Beaver-Dallam-Sherman-Hansford-Ochiltree-Lipscomb-
Hartley-Moore-Hutchinson-Roberts-Hemphill-Oldham-Potter-Carson-
Gray-Wheeler-Deaf Smith-Randall-Armstrong-Donley-Collingsworth-
514 PM CDT Thu Apr 27 2017

This Hazardous Weather Outlook is for the Texas and Oklahoma
Panhandles.

.DAY ONE...Tonight.

Thunderstorms will be possible through this evening across the
Oklahoma Panhandle and the northern and eastern Texas Panhandle. A
storm or two may become severe with damaging winds the main
threat.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Thunderstorms will be possible again Friday afternoon into Friday
night across portions of the Panhandles. Severe thunderstorms
will be possible for the southeastern Texas Panhandle Friday
evening into early Saturday morning with large hail being the
main threat.

Freezing temperatures will be possible Saturday and Sunday
mornings across the western half of the Panhandles.

Winter precipitation is possible across much of the Panhandles
Saturday into Sunday morning. Snow accumulation may approach
advisory criteria in the northern and western halves of the Texas
Panhandle and the Oklahoma Panhandle through Sunday morning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 28, 4:20 AM CDTWinter Storm WarningAMADallam, Hartley, Sherman56 hr
Apr 28, 4:52 PM CDTSpecial Weather StatementAMACarson38 min

Nearby

Winter Storm Watches in Texas, 2017Winter Storm Watches in Oklahoma, 2017Every winter storm watch in 2017

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.