textproduct: El Paso

KEY MESSAGES

Updated at 530 AM MDT Mon Sep 28 2026

- Moisture from tropical remnants of Polo will bring more widespread showers and thunderstorms to the Borderland through Tuesday night. Storms will be capable of heavy rain, gusty winds, and flash flooding, especially over locations that have already received heavy rain in recent weeks.

- New rain amounts around 2 inches across much of southern New Mexico, with localized areas receiving 3 to 4 inches. A Flood Watch is in effect into Wednesday morning.

- Drier weather expected Thursday through the weekend as the moisture is pushed eastward. Temperatures remaining cool into next weekend.

DISCUSSION

Issued at 1100 PM MDT Sun Sep 27 2026

...FLOOD WATCH IN EFFECT FROM MONDAY AFTERNOON THROUGH WEDNESDAY MORNING...

Two weather features to focus on in the short term are the upper low currently centered over northern California and Hurricane Polo spinning off the Baja California coast. Tropical steering pattern is favorable for Polo to drift north on Monday, making likely landfall over Baja California Sur during the evening hours. At the same time, the mid-latitude Pacific low aloft will make a southeast dive down to the Colorado River Valley, forced by a strengthening 75-knot jet streak on its backside. A weakening Polo will latch onto this stronger mid-latitude flow, shifting it northeast into Sonora/Chihuahua and straight toward El Paso on Tuesday.

Monday will feature a rapid moisture increase locally, thanks to the approaching tropical remnants. Veering of mid-level winds to the south ahead of the Pacific low will pull in deep, tropically- sourced moisture into southern New Mexico and far west Texas. Precipitable water values, measured at just 1.1" this evening (00Z KEPZ RAOB), will spike to 1.5-1.6" Monday evening. This may break seasonal moisture records for El Paso, and is easily 3 to 4 standard deviations higher than usual for the end of the monsoon season. This moisture-rich atmosphere, combined with PVA and increasing diffluent flow aloft, will lead to widespread showers and thunderstorms area wide starting as early as Monday afternoon.

Good confidence in rain for all local zones Monday night through Wednesday morning as the upper low pulls up tropical moisture like a fire hose into New Mexico and West Texas. 48-hour rainfall forecasts suggest widespread totals ranging from 1.00-2.00". NBM guidance backs this up. Stronger storms and training (or multiple rounds) of rain showers over the same areas will lead to localized 3-4". Soil saturation is very high right now, so rain will lead to rapid runoff and flash flooding quickly. A Moderate (Level 3 of 4) Risk of flash flooding is in place almost area-wide for Tuesday. Of particular concern for me will be the Sacramento Mountains, which have already had an above-normal precipitation season and significant flooding over the past two weeks. A Flood Watch is in effect area-wide from Monday afternoon through Wednesday morning. WFO El Paso will be proactive with flood warnings in areas with recent heavy rains if needed Tuesday- Wednesday.

On top of the heavy rain risk, the passing tropical depression may still have some stronger winds associated with it. 00Z HRRR run tonight was of particular concern, and recent NAM runs have also picked up on the potential for gusty conditions Tuesday evening as Polo moves through. Increased forecasted winds for Tuesday afternoon/evening, especially for El Paso, Hudspeth, Otero counties where strong winds out of the south just ahead of the anticipated storm track could lead to gusts in the 30-40 mph range.

Both GFS and ECMWF global models show a track of the upper low progressing across central NM on Wednesday. Rain showers will slowly decrease in coverage Wednesday morning, with the remnants of Polo quickly dissipating. Subsident "dry-slotting" at the base of the low will lead to drier weather for our area by Wednesday afternoon.

Once all this action passes, it looks like a fairly "boring" weather pattern for the start of October. Strengthening upper high over the U.S. Southwest will usher in a much-needed break from rainfall. Continued east surface flow could keep temperatures below normal through the rest of the week. Lowland highs lingering in the upper 70s into next weekend seems like the best bet right now.

AVIATION

(12Z TAFS) Issued at 530 AM MDT Mon Sep 28 2026

Clouds increase through the day with virga showers developing by the afternoon. Convection develops during the afternoon, progressing NE. Showers will be scattered to widespread after 21z. Embedded TS expected in the evening with lower confidence overnight in lightning activity. TS may lower VIS to MVFR or IFR due to heavy rain. Clouds lower to about 030 late in period, most likely at KTCS and KDMN. Some gusts to upper teens from S-SE this afternoon, otherwise winds AOB 8kts.

FIRE WEATHER

Issued at 530 AM MDT Mon Sep 28 2026

No fire weather concerns are forecast through the week. Increasing moisture and rain chances today, becoming widespread by tonight. High rain chances continue through Tuesday night with a medium-high risk of flash flooding, worsened by saturated soils from last weeks' rainfall. Winds will be breezier today from the south with near-normal temperatures. Cooler tomorrow with possibly strong winds in the evening for eastern areas as Polo's remnants come across the region. Rain chances quickly decrease Wed AM behind the passing upper low with mainly dry conditions beginning Thu. Temperatures remain below normal into next weekend.

Min RHs range from 35-55% today, rising to 60-90% Tue. Vent rates will be fair to good this afternoon, then mostly poor tomorrow.

PRELIMINARY POINT TEMPS/POPS

El Paso 65 77 61 74 / 90 100 70 0 Sierra Blanca 62 78 58 72 / 90 70 70 10 Las Cruces 62 73 56 72 / 80 100 70 0 Alamogordo 61 74 56 72 / 90 100 90 30 Cloudcroft 48 55 42 51 / 90 100 90 40 Truth or Consequences 62 69 54 72 / 100 100 70 20 Silver City 57 65 48 65 / 100 100 70 20 Deming 61 73 54 73 / 90 100 60 0 Lordsburg 62 71 54 70 / 90 100 60 20 West El Paso Metro 65 77 60 74 / 90 100 70 0 Dell City 65 81 61 76 / 80 80 80 0 Fort Hancock 68 86 63 80 / 90 70 70 10 Loma Linda 61 72 56 67 / 90 90 80 0 Fabens 66 82 61 77 / 90 90 70 0 Santa Teresa 63 75 58 73 / 80 100 70 0 White Sands HQ 64 75 59 74 / 90 100 80 10 Jornada Range 62 72 55 72 / 80 100 80 20 Hatch 63 74 56 75 / 90 100 70 10 Columbus 64 75 58 75 / 80 90 60 0 Orogrande 62 73 56 71 / 90 100 80 10 Mayhill 54 67 49 65 / 90 100 80 20 Mescalero 53 65 47 61 / 90 100 90 50 Timberon 52 62 46 59 / 100 100 90 30 Winston 54 64 45 65 / 90 100 70 20 Hillsboro 60 71 52 72 / 100 100 60 10 Spaceport 60 70 54 72 / 100 100 70 20 Lake Roberts 54 64 45 64 / 100 100 70 20 Hurley 57 68 49 68 / 90 100 60 10 Cliff 61 71 54 71 / 100 100 70 30 Mule Creek 57 66 49 67 / 100 100 70 30 Faywood 60 67 51 68 / 100 100 70 0 Animas 63 73 54 73 / 90 100 50 0 Hachita 61 72 54 72 / 90 100 60 10 Antelope Wells 62 73 55 74 / 80 100 60 0 Cloverdale 59 67 52 68 / 80 100 70 10

EPZ WATCHES/WARNINGS/ADVISORIES

TX...Flood Watch from noon MDT today through late Tuesday night for Eastern/Central El Paso County-Northern Hudspeth Highlands/Hueco Mountains-Rio Grande Valley of Eastern El Paso/Western Hudspeth Counties-Rio Grande Valley of Eastern Hudspeth County-Salt Basin-Southern Hudspeth Highlands- Western El Paso County.

NM...Flood Watch from noon MDT today through late Tuesday night for Central Grant County/Silver City Area-East Central Tularosa Basin/Alamogordo-East Slopes Sacramento Mountains Below 7500 Feet-Eastern Black Range Foothills-Lowlands of the Bootheel-Northern Dona Ana County-Otero Mesa-Sacramento Mountains Above 7500 Feet-Sierra County Lakes-Southeast Tularosa Basin-Southern Dona Ana County/Mesilla Valley- Southern Gila Foothills/Mimbres Valley-Southern Gila Region Highlands/Black Range-Southwest Desert/Lower Gila River Valley-Southwest Desert/Mimbres Basin-Uplands of the Bootheel-Upper Gila River Valley-West Central Tularosa Basin/White Sands-West Slopes Sacramento Mountains Below 7500 Feet.