Gallup, NM 87302 Weather

Key Messages

Issued at 509 PM MDT Tue Oct 20 2026

- Flash flood risk increases in northwest New Mexico Wednesday, spreading eastward into central New Mexico late Thursday into Friday.

- A few strong to severe storms in western New Mexico Wednesday could produce damaging outflow wind gusts and large hail. The severe threat extends into central New Mexico Thursday.

- Isolated to scattered showers and storms will focus over western and central New Mexico today. Brief gusty outflow winds and lightning are the main hazards.

Short Term

(This evening through Wednesday night) Issued at 120 PM MDT Tue Oct 20 2026

Shortwave ridging is building into place over the region in the wake of a departing shortwave trough over CO/UT. Strengthening southwesterly shear will help afternoon showers and storms get going over the southwest mountains where abundant low level moisture remains, highlighted by surface Td's in the 50s. SW-NE steering flow will take these scattered showers with a few embedded thunderstorms into the Rio Grande Valley from Socorro to ABQ to Santa Fe late this afternoon and evening. Southerly flow at the surface will continue to maintain an increased level of boundary layer moisture into southern and central portions of NM tonight into Wednesday morning. Combined with light and variable winds, the abundant near surface moisture will allow for some patchy fog development over portions of central and eastern NM Wednesday morning.

Wednesday continues to see the upper level pattern become sharply amplified with AZ/NM stuck between a 555-558dm H5 closed low off the CA coastline and a ridge of high pressure aligned N-S over the TX Big Bend area and eastern NM. Current satellite shows the beginnings of the suptropical jet bringing a steady flow of moisture into the Baja Coast now, expected to override the Desert Southwest Wednesday afternoon. PWAT climbs to the 0.85" to 0.95" range with scattered to numerous showers and thunderstorms along the Mogollon Rim northward over much of Navajo Nation stretching into the Four Corners region and northwestern NM Wednesday afternoon. A veering wind profile looks to yield 35-45kts of bulk shear alongside SBCAPE of ranging from 500-1000 J/kg supports a current marginal risk of strong to severe storms over western NM Wednesday afternoon and evening. As the H5 closed low begins to come ashore SoCal Wednesday night, a steady flow of fast moving thunderstorms will continue to cross SW- NE thru northeastern AZ and into western NM. Flow between the low and the ridge of high pressure will become more meridional N-S in nature, thus limiting the eastward progression of storms further into NM thru Wednesday night. This will be the first phase of a multi-day heavy rain event across the state lasting into the weekend. With training storms capable of producing locally heavy rainfall supporting a marginal to slight risk of excessive rainfall, a Flood Watch was laid out for western NM mainly along and west of the Continental Divide. This Flood Watch is likely to be expanded eastward into central and eastern NM for the Thursday thru Friday timeframe.

Long Term

(Thursday through Monday) Issued at 120 PM MDT Tue Oct 20 2026

Thursday begins the second phase of this multi-day heavy rain event with a vortmax rotating around the southeastern periphery of the H5 low and over the Desert Southwest. This feature will act to push the main area of fast moving SW-NE moving thunderstorm activity eastward toward the Rio Grande Valley and central mountain chain of NM. Remaining in the warm sector of this storm system as well the subtropical source region for the anomalous moisture plume, snow levels will remain very high over NM. Much if not nearly all of this event's precipitation will be in the form of rain, even over the northern high terrain. This is also resulting in a rain on snow threat over the CO San Juans, in turn increasing the risk of higher river flows along the San Juan basin of northwestern NM. Areas along river banks will be susceptible to flooding in this area.

Otherwise, Thursday and Thursday night into Friday morning sees the bulk of the heavy rainfall risk over western, central, and northern NM. Whether from fast moving storms repeatedly passing over the same lower to mid-level elevations or orographically enhanced precipitation over the western and northern mountains, excessive rainfall threatening flash flooding will be a persistent concern thru this timeframe. Generally speaking, lower to mid-elevation areas of central and western NM look to receive 0.50" to 0.75" with locally higher amounts upwards of 1.00+". The higher terrain of the southwestern mountains, near the Continental Divide in west-central NM, and the Jemez and Tusas Mountains look to catch 1 to 2 inches with locally higher amounts upwards of 2 to 4 inches. A marginal to slight risk of excessive rainfall was maintained by the WPC as a result. Low lying and poorly drained areas, low water crossings, urban areas, and recent burn scars are most at risk. Timing favors areas along the Rio Grande Valley from Socorro to ABQ to Santa Fe to Taos Thursday night through Friday morning for the heaviest round(s) of thunderstorm rain.

The final phase of this event has seen numerical model guidance come into better agreement with a secondary H5 low closing off over western AZ. This feature looks to continue tapping into subtropical moisture, bringing it up into central and eastern NM late Friday and into the weekend. Areas along and east of the central mountain chain will then be favored for repeated rounds of showers and thunderstorms, increasing their own risk for flooding impacts. Areas along and west of the Rio Grande Valley look to dry out during this time, with one more round of showers/storms favored thru northwestern NM Saturday afternoon as the H5 low looks to track northeastward into UT. Precipitation chances and intensities look to slowly dwindle for central and eastern NM Sunday and into next week.

Aviation

(00Z TAFS) Issued at 509 PM MDT Tue Oct 20 2026

Isold SHRA/TS late this afternoon will dissipate this evening while mid and upper level cigs increase from southwest to northeast overnight. There is <30% chance of patchy IFR fog within western valleys, the Estancia Valley, and southeast NM around sunrise. There is a 10-20% chance of IFR cigs developing over southeast NM from near Roswell to Carlsbad around sunrise. Cigs will lower over western NM Wednesday afternoon while increasing coverage of SHRA/TS spreads northeast across the area.