textproduct: NWS Flagstaff

SYNOPSIS

Seasonable temperatures and dry conditions continue through Wednesday. Chances for scattered light showers and slightly cooler temperatures arrive Thursday and Friday. High pressure builds into Arizona over the weekend, ushering in a return of warmer temperatures and dry conditions.

DISCUSSION

Dry westerlies over Arizona will continue through Wednesday as the northern and southern streams battle over the southwestern United States. Daytime temperatures have recovered a few degrees in this pattern, but will still be just a bit below normal. Wind speeds have also relaxed, with just average southwest wind speeds at this point.

By Thursday, the trough we have been waiting for has fractured quite a bit as the northern stream has disconnected and the remaining low in the EASTPAC is very weak and disorganized. This trough will move through our area Thursday and Friday, but now much farther south and any subtropical tap is now in southern New Mexico and west Texas.

We will see some increase in boundary layer moisture when the trough comes through and then the cold pool aloft may be enough to generate patchy convection, but probably not until Friday afternoon. Bottom line, the trough position and strength has changed so much that QPF is almost not a factor at this point.

Finally, by next weekend, more zonal flow with a slight amplification late in the weekend will bring dry and warmer conditions back to the area, once again.

AVIATION...Wednesday 29/06Z through Thursday 30/06Z

Look for VFR conditions. Winds light and variable overnight through most of Wednesday morning, then becoming SW-W at 10-20 kts midday through the afternoon. Winds turning light again during the evening.

OUTLOOK...Thursday 30/06Z through Saturday 02/06Z...Mainly VFR conditions. A weak weather disturbance will deliver increasing clouds along with isolated -SHRA/-SHSN later on Thursday into Friday, mainly along and east of I-17/US-89. Isolated -TSRA will be possible Friday afternoon toward the AZ/NM border. Brief periods of MVFR conditions and mountain obscuration are likely in any shower activity. Winds W-NW at 10-20 kts both Thursday and Friday.

FIRE WEATHER...Wednesday and Thursday

Expect average temperatures with dry conditions on Wednesday. Moisture increases on Thursday as temperatures cool slightly. Slight chances for showers are forecast Thursday afternoon, mainly along the Mogollon Rim and White Mountains eastward. Plan on west-southwest winds, 10 to 20 mph, on Wednesday becoming west-northwest on Thursday.

Friday through Sunday...The unsettled pattern persists through Friday with afternoon humidity in the 15 to 30% range, cool temperatures, and slight chances for showers. Drier and warmer conditions are expected for this weekend. North-northwest winds, 10 to 20 mph, persist on Friday, becoming south-southwest for Saturday and Sunday.

FGZ WATCHES/WARNINGS/ADVISORIES

None.