textproduct: Medford

UPDATE

Aviation Discussion Updated.

PREV DISCUSSION

/Issued 1217 AM PDT Sun Apr 5 2026/

DISCUSSION...Satellite imagery early this morning shows a wide expanse of high clouds moving over the area ahead of a weak shortwave slowly moving north just offshore. A thermal trough set up along the Oregon coast will keep us warm and dry through the weekend with temperatures pushing into upper 70's and perhaps lower 80's over some locations.

Fog will likely fill into the Umpqua Valley by sunrise as there is some boundary layer moisture there, although the drier air today could dry things out. Plus, the higher clouds could reflect some of that long wave radiation back to earth. In any case, we kept fog in the forecast, although confidence still isn't high in the formation.

Sunday will be another warm day as the thermal trough begins to move farther inland. However, our temperatures stay put with highs in the upper 70's west of the Cascades and low 70's east of the Cascades.

Monday is an interesting day as the ridge breaks down and a short wave moves into southern Oregon early in the day. A few models and about 15-25% of GEFS/ECMWF ENS are bringing precipitation to the Cascades and other portions of our forecast area. Looking at GFS model soundings, there is convective available potential energy(CAPE) along the Cascade crest with some of that CAPE is between -10C to -20C. The latest and greatest experimental rapid refresh forecast system(RRFS) is modeling echos >40dbz with some lightning east of the Cascades mostly in our CWA. Therefore, we put some thunderstorms in the forecast along the Cascades, although they will most likely be showers with some occasional rumbles of thunder. Its more of a question of where these will develop not if they will develop. Keep a look out for showers east of the Cascades on Monday as well.

By Tuesday, a cold/stationary front will settle over central Oregon with a cutoff low off the coast of northern California. The models are bringing a 10-20% chance of rain to the area. A trough in Canada then slides down the Cascades and it seems the chances of rain increase to about 50% on Wednesday. There is still a lot of variability on Wednesday with some ensemble members keeping things completely dry, while others bring in plenty of precipitation with some thunderstorms. The variability could continue give the split flow and cut off low in the Pacific. Given the higher snow levels, don't expect any significant snow with the precipitation on Wednesday.

AVIATION...05/12Z TAFs

VFR conditions will persist through the TAF period for most the area. Some areas of LIFR/IFR conditions could return to the Umpqua Basin (including Roseburg) around sunrise this morning. Over the coastal waters, LIFR/IFR conditions in marine stratus may develop south of Cape Blanco, then spread into areas north of Cape Blanco later today. Areas along the coast will see increasing chances for LIFR/IFR conditions with marine fog and stratus late this evening.

MFR WATCHES/WARNINGS/ADVISORIES

OR...None.

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 AM PDT this morning for PZZ370-376.