Area Forecast Discussion
Issued by NWS Amarillo, TX

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS64 KAMA 212035
AFDAMA

Area Forecast Discussion
National Weather Service Amarillo TX
335 PM CDT SAT MAY 21 2016

.Discussion...
Thunderstorms that develop this afternoon across the western
Panhandles will move east this evening with at least a marginally
severe wind/hail threat persisting through late evening.
Deepening moisture and increasing precipitable water values per
short term guidance and trends in the upstream GPS PWAT sites,
combined with relatively slow storm motions are supportive of
locally heavy rainfall amounts and possibly flooding potential,
particularly later this evening in the southern Texas Panhandle. For
specifics on convective initiation and potential severe please see
the previously issued mesoscale discussion. Updates on mesoscale
evolution will be sent as needed through the afternoon and evening.

There is a decent signal in some of the models of warm/moist
advection process keeping convection going across the southern
portion of the Texas Panhandle through the night. Most of the
forecast soundings still show evidence of ridging/subsidence for
most of the night, but the eastward progression of the ridge may be
enough for some activity late especially in the southeast Texas
Panhandle where the WAA signal is maximized. Kept low probabilities
to account for this mainly focused on the southeastern Texas
Panhandle.

Modest ascent will overspread the area tomorrow in diffluent upper
flow regime. A sharpening dryline across the western Panhandles
should focus thunderstorm development during the afternoon in a
moderately unstable environment with MLCAPE of 2,000-2,500 J/KG. 0-6
km bulk shear of around 30 to 40 knots should be sufficient for
storm organization and supercells. Large hail and damaging winds
will be the primary threat although with relatively low LCL heights
generally less than 1,000m isolated tornadoes will be possible. The
best chance for a tornado would be during the evening as low level
jet strengthens causing low level shear to increase and before
significant boundary layer stabilization occurs.

Troughing to our west continues through mid-week before accelerating
eastward toward the Panhandles by the end of the week. Until then
mid-level momentum should allow the dryline to mix/sharpen across
the far eastern Panahandles and this convection should be limited to
this area. We will need to monitor trends in the short term guidance
as the time nears in case models are mixing the dryline too far east
as has been the case lately. This is a more synoptically active
scenario with fairly decent cross-boundary mean flow, thus the
reasoning for not adjusting westward at this time. If models trend
slower and more amplified with approaching truogh, we will likely
need to introduce at least low probabilities of convection in the
east portion of the Panhandles.

BRB

&&

.Preliminary Point Temps/Pops...
Amarillo TX                60  80  59  88  57 /  40  50  40   5   5
Beaver OK                  62  83  62  88  60 /  30  40  50  20  20
Boise City OK              56  83  53  84  51 /  30  30  10   5   0
Borger TX                  63  83  62  89  61 /  40  50  50  10   5
Boys Ranch TX              60  85  58  89  56 /  40  50  20   5   0
Canyon TX                  60  81  58  88  56 /  40  50  40   5   5
Clarendon TX               62  80  63  88  62 /  30  50  50  20  20
Dalhart TX                 56  84  54  87  52 /  40  30  10   0   0
Guymon OK                  61  84  59  87  56 /  40  50  30   5   5
Hereford TX                59  83  57  89  55 /  40  50  20   0   0
Lipscomb TX                64  81  64  88  62 /  30  40  50  20  20
Pampa TX                   59  80  62  87  60 /  30  50  50  20  10
Shamrock TX                62  80  64  88  64 /  30  40  50  30  20
Wellington TX              63  81  65  90  65 /  30  30  50  30  20

&&

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

&&

$$

6/17



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.