609
FXUS64 KEPZ 041659
AFDEPZ

Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
1059 AM MDT Thu Jul 4 2024

...New AVIATION...

.SYNOPSIS...
Issued at 344 AM MDT Thu Jul 4 2024

Happy 4th of July! Temperatures this afternoon and evening will be
hot across the desert lowlands. A Heat Advisory has been issued
most of the El Paso County and the Rio Grande Valley of Hudspeth
County. An isolated storm or two is possible today, mainly focused
across west Texas. A backdoor front will move through, increasing
moisture and rain chances across the area on Saturday. Dry
northwest flow dominates on Sunday with hot temperatures expected.

&&

.DISCUSSION...
Issued at 344 AM MDT Thu Jul 4 2024

High pressure aloft over the Deep South and Southern Mississippi
River Valley, along with a strengthening upper level high off the
coast of California will be the synoptic scale features driving the
weather locally across the Desert SW through the weekend and into
next week. That said, no significant changes from previous forecast
packages.

First and foremost, Happy 4th of July!!! For today, expected quiet
and generally dry weather conditions across the forecast area. The
strengthening high pressure aforementioned above will move
onshore across western CONUS with it`s eastern periphery nosing
into the Four Corners vicinity. North/northwesterly flow will
increase as a result, pushing the deep Monsoonal moisture slowly
towards the south and southeast. This dry influence along with
increasing 500mb heights will decrease rain chances across the
northern portions of the CWA with the focus for isolated storm or
two across West Texas and along the International Border. There
remains low-end chances of an isolated storm or two over the Gila
and Sacs due to orographics.

After a relatively "cool" and cloudy day on Wednesday, hot
temperatures will be the main weather focus for the 4th of July.
Increasing 500mb heights and 850mb temps between 31-34C, high
temperatures this afternoon will top out between 100-105 across the
desert lowlands. That said, a Heat Advisory will be in effect from
noon today through midnight tonight for most of El Paso County and
the Rio Grande Valley of Hudspeth County. Although NBM probs show 20-
40 percent chance of temps reaching 105, confidence is high that
impacts will be felt across the El Paso metro due to it being a
holiday with plenty of outdoor activities/festivities going on
across the city, hence the Heat Advisory issuance. If you do have
outdoor plans this afternoon and evening, please take extra
precautions like: drink plenty of fluids, try to stay in the shade
if outdoors, and reduce/limit strenuous activities outdoors. Areas
across the desert lowlands that aren`t within the Heat Advisory,
like Las Cruces, Deming, Alamogordo, etc. Please take the same
precautions, even though there`s not a Heat Advisory for these
locations, Moderate risk for heat-related impacts will be felt.

For Friday, a backdoor frontal boundary will move east to west
across the area. This will increase surface and low-level moisture
across the area, along with the return of isolated to scattered
showers and thunderstorms. Temperatures on Friday will respond to
the boundary intrusion and cool a few degrees from today. daily
afternoon and evening isolated to scattered showers/storms will be
possible. Temperatures each afternoon will hover right around the
100 degree mark with light winds.

By the weekend, isolated to scattered showers and storms will be
possible on Saturday, mainly focusing for areas along and east of
the Rio Grande Valley. On Sunday, the strong upper level high
pressure over western CONUS will expand and nose in from the west.
Conditions will dry out with temperatures increasing back above Heat
Advisory thresholds for places like El Paso and Las Cruces. Heat
headlines will likely be needed. By the start of next week, model
inconsistencies with lower forecast confidence arise.

&&

.AVIATION...
(18Z TAFS)
Issued at 1053 AM MDT Thu Jul 4 2024

P6SM FEW-SCT120-150 SCT-BKN200 with cloud cover gradually
decreasing from N to S after 00Z. Isolated to scattered 1-3SM TSRA
BKN050-070 mid afternoon through early evening, mainly east of a
KALM-KELP line. Some outflow winds could push further west with
gusts to 30KTS, but in general, winds will start out N to NE AOB
12KTS shifting to the E to SE at 5-15KTS overnight.

&&

.FIRE WEATHER...
Issued at 344 AM MDT Thu Jul 4 2024

Fire weather concerns are LOW to ELEVATED for Thursday. Isolated
showers and thunderstorms will be possible during the afternoon and
evening, focusing across Far West Texas. Much drier air will
infiltrate the forecast area with critically low (10-15%) Min RH
values for most of the forecast area, excluding the Sacs and
Hudspeth County. Min RH values will be greater than 25 percent
areawide, 30-50 percent over the mountains. High temperatures this
afternoon will run 5-8 degrees warmer than yesterday under deep
afternoon mixing of 10-15 kft. 10-100hr fuels remain moist with ERC
values at or below the 50th percentile. Winds will be light and
mainly diurnal and terrain driven under weak west/northwest flow.

On Friday, a backdoor frontal boundary will push east to west across
the area during the Thursday night and early Friday morning hours.
Winds will become breezy along and behind, generally out of the east
at 10-20 mph. Moisture values will increase on Friday with Min RHs
of >20% along and east of the Rio Grande Valley, areas along and
west of the Continental Divide will still see critically low Min RH
values. An increase in shower/storm activity will accompany the
moisture on Friday, with the highest probabilities over the
Sacramento Mtns and Far West TX.

Isolated to scattered showers and storms remain in the forecast for
Saturday, with another dry air intrusion from the west on Sunday.

&&

.PRELIMINARY POINT TEMPS/POPS...
El Paso                 105  80  99  76 /  20  20  50  40
Sierra Blanca            97  71  90  68 /  60  50  60  40
Las Cruces              103  73  99  72 /  10  20  30  30
Alamogordo              101  68  95  66 /  10  10  40  30
Cloudcroft               78  53  69  50 /  20  20  70  30
Truth or Consequences   100  71  96  70 /   0   0  20  20
Silver City              95  66  92  65 /  20  20  30  20
Deming                  102  71  99  70 /  20  20  30  30
Lordsburg               100  69  99  69 /  20  20  20  30
West El Paso Metro      102  78  97  75 /  20  30  40  40
Dell City               102  73  94  69 /  30  30  50  50
Fort Hancock            104  76  97  73 /  50  50  60  40
Loma Linda               95  71  89  68 /  30  20  60  50
Fabens                  105  78  98  75 /  40  30  50  40
Santa Teresa            100  73  95  72 /  20  20  40  40
White Sands HQ          101  76  95  73 /  20  20  50  30
Jornada Range           101  68  96  68 /  10  10  50  30
Hatch                   104  69  99  69 /  10  10  30  30
Columbus                101  74  97  73 /  20  30  30  40
Orogrande               100  73  93  69 /  20  10  50  30
Mayhill                  90  58  77  55 /  30  20  70  30
Mescalero                89  58  81  54 /  20  10  70  30
Timberon                 86  57  79  54 /  30  20  70  30
Winston                  92  58  88  57 /  10  10  30  20
Hillsboro                98  68  94  66 /  10  10  30  30
Spaceport               101  65  95  65 /  10  10  30  30
Lake Roberts             94  60  92  60 /  20  10  30  30
Hurley                   98  65  95  63 /  20  20  30  30
Cliff                   104  64 103  65 /  20  10  30  30
Mule Creek               98  67  97  66 /  20  10  20  20
Faywood                  96  68  92  65 /  20  20  30  30
Animas                  100  68  99  69 /  30  30  30  30
Hachita                  99  68  98  68 /  20  20  20  40
Antelope Wells           98  68  98  68 /  40  30  40  50
Cloverdale               93  65  94  66 /  40  40  40  30

&&

.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...Heat Advisory until midnight MDT tonight for TXZ418-419-423-424.

NM...None.
&&

$$

FORECASTER...26-Grzywacz