FXUS65 KGJT 191115

AFDGJT



Area Forecast Discussion

National Weather Service Grand Junction CO

515 AM MDT Tue Aug 19 2025



.KEY MESSAGES...



- Hot and dry conditions remain through the end of the week,

  with near-record high temperatures expected.



- A few isolated showers or thunderstorms will be possible over

  the San Juans in the afternoon.



- Confidence continues to increase that moisture will return

  late this week, increasing chances of precipitation and

  bringing some cooler temperatures.



&&



.SHORT TERM /THROUGH WEDNESDAY/...

Issued at 254 AM MDT Tue Aug 19 2025



High pressure will be in control for the next several days over the 

Four Corners region. This will result in generally warm, clear, and 

quiet conditions. Being located near the center of the high will 

keep winds light, limiting fire weather concerns. However, this will 

also allow the heat to build across the region. Temperatures will 

run 5-10 degrees above normal, resulting in highs in the upper 90s 

to low 100s across the desert valleys, and highs in the 80s for the 

mountain towns. Many locations will see afternoon highs challenge 

records, including at the Grand Junction Regional Airport, where the 

record high today is 98F and the current forecast high is 99F. The 

only areas that might see some relief from the heat will be along 

the central and especially southern Divide mountains. Just enough 

moisture is being pulled up from the south to allow for the 

formation of some afternoon clouds and an isolated shower or two. 

The high shifts just slightly tomorrow, allowing a bit more moisture 

to work into the San Juans. This means a slightly higher chance of 

showers and thunderstorms during the afternoon, 40-50% over the 

highest terrain. However, the chances of wetting rain will remain 

limited thanks to that hot, dry surface air. Otherwise, Wednesday 

will be a rinse and repeat kind of day, with near record high 

temperatures and abundant sunshine.



&&



.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...

Issued at 254 AM MDT Tue Aug 19 2025



Clockwise flow around the high will advect moisture into the 

area on Thursday and Friday. This should contribute to more showers 

and storms especially over the high terrain. Confidence is low on 

the coverage and rainfall amounts. It is common for the moisture to 

take a few days to reach down to the surface. Warm temperatures may 

also inhibit precipitation from reaching the ground. This weekend 

the high pressure sinks to the south, which allows the moisture 

advection to continue. The PWAT values show that the peak moisture 

will be on Saturday, so expect more widespread showers. As with most 

moisture surges the morning cloud cover will dictate how much 

instability can be reached by the afternoon. This in turn is the 

difference between light showers and strong storms with heavy 

downpours.



The increased moisture and widespread cloud cover and showers 

expected for the weekend will also bring cooler temperatures. Highs 

will remain above normal Thursday and Friday, but current guidance 

has temperatures dropping closer to normal values by Sunday. 

Potentially even dropping below normal into early next week, should 

the moisture stick around to that point.



&&



.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...

Issued at 513 AM MDT Tue Aug 19 2025



Skies will remain mostly clear, with VFR conditions prevailing

for the next 24 hours. Winds will be generally light and follow

typical terrain driven patterns. Some mid level clouds and a few

isolated showers or thunderstorms are possible over the higher

elevations of the San Juans, but should have a limited, if any, 

impact on terminals.



&&



.GJT WATCHES/WARNINGS/ADVISORIES...



CO...None.

UT...None.



&&



$$



SHORT TERM...BGB

LONG TERM...KJS/TGJT

AVIATION...TGJT