textproduct: Medford

Updated AVIATION Discussion

AVIATION...05/00Z TAFs

Smoke is the main aviation impact over the next few days. Visibility restrictions around 3 to 6 miles are most likely across all the terminals at times during this TAF cycle. The best chances seem to be late afternoon when fresh smoke comes down in the northerly flow, with improvement expected the following early afternoon as winds increase for the day. The fires are far enough away that the really thick smoke under 3 miles seems unlikely. MVFR visibilities seem more probable through the TAF period.

Aside from smoke, the marine layer looks like it will make a return tonight, with confidence highest for IFR/LIFR impacts south of Cape Blanco. With the flow turning more onshore north of Cape Blanco, some patchy LIFR/IFR ceilings are possible in the Coquille Basin tonight, which could briefly impact North Bend late tonight/early Wednesday morning.

PREV DISCUSSION

/Issued 255 PM PDT Tue Aug 4 2026/

KEY MESSAGES...

* A heat wave will create moderate heat risk over the majority of our region with major heat risk possible around the Rogue Valley.

* Smoke from fires to our north will create reduced air quality across the region.

* A dry forecast continues with no thunderstorms or wetting rain in the forecast.

DISCUSSION...

The start of our heatwave has begun this afternoon as highs start push towards the mid 100's. A thermal trough remains overhead with the inverted 850 mb heights and 1000-500 mb thickness values over valleys west of the Cascades. Lows will warm in the lower to mid 60's west of the Cascades. East of the Cascades, lows will drop down into lower 50's, so people should have an easier time recovering in that section of our area.

Wednesday and Thursday should be as warm as today with moderate heat risk as the very least. There are some pockets of major heat risk here in the Rogue Valley as we're in the mid 100's with lows in the lower to mid 60's. Again, the duration of the heat wave could result in heat related illness to those sensitive to heat. Medford will also challenge records on Wednesday with a high 106 current in the forecast. That would tie the old record in 1972.

Smoke will also be an impact through the forecast period with many fires burning to our north. With north, east and northeast winds, thicker smoke will make it's way down to southern Oregon. Air Quality will be impacted in some locations, although we're not expecting widespread unhealthy air. Right now, an air quality advisory is out for eastern Douglas County until further notice according to Oregon DEQ. Wind direction will change a bit with the thermal trough retreating farther east, perhaps around Wednesday night and Thursday. The ridge should also start to break down and lead to more westerly flow. This will help us in south western Oregon by pushing smoke from most of the fires east of us towards the end of the week.

Models continue now show a trough riding over the ridge around the Friday night and Saturday timeframe. This should result in a decrease in temperatures at the very least. The NBM has many areas dropping back to their climatological norms by next week starting Sunday.

Lastly, it remains a dry forecast through the extended period with basically no signal for thunderstorms or wetting rain in our region. Although we did look through the 12Z ECMWF ensemble members and 1 out 50 is showing a little QPF Tuesday August 11th. So there is hope, just not much. -Smith

MARINE...Updated 230 PM PDT Tuesday, August 4, 2026...Northerly winds will keep seas rather steep through the remainder of the afternoon and evening hours. The fresh swell prompted a hazardous seas warning, although that will be replaced by slightly lower steep seas through Wednesday. Overall, conditions remain hazardous to smaller crafts through early Wednesday before seas just drop below small craft criteria. -Smith

FIRE WEATHER...Updated 100 PM PDT Tuesday, August 4, 2026... Ridging aloft and a thermal trough at the surface will produce persistent near-critical to critical fire weather concerns through the week. Temperatures will remain hot through the week, peaking at about 10 to 15 degrees above normal Wednesday/Thursday, before cooling slightly to more normal or just slightly above normal values into the weekend and early next week.

Poor RH recoveries have been observed across all of SW Oregon and northern California upper slopes/ridges early this morning. Some guidance is showing RH only recovering into the low 20s (upper teens?!) through Thursday, while daytime minimum humidities could easily drop into the single digit percentages. With these hot, dry, and windy conditions in the valleys during the day today and Wednesday, we are expecting to reach critical conditions across much of the area. A Red Flag Warning is in effect for the Illinois and Rogue valleys, as well as the Siskiyous and southern Oregon Cascades through this evening, with another Red Flag Warning issued for these same areas in addition to the Umpqua Basin and western and south central Siskiyou County Wednesday afternoon and evening.

Although poor overnight recoveries and breezy east winds return again for the mountains tonight, conditions should improve just enough (mainly slightly weaker winds) to preclude continuing the Red Flag through the overnight hours. Guidance shows only minimal improvement, if any, in wind and humidity during the day Wednesday, in addition to much more instability as the thermal trough pushes inland. With Wednesday/Thursday being the hottest days, and with continued dry, windy, and unstable conditions, critical fire weather conditions are expected over portions of the area yet again Thursday, including the Rogue, Illinois, and Applegate valleys, where Red Flag conditions are possible each day this week.

We may see some slight cooling and slight improvement to overall winds and humidities beginning Friday, but it may not be enough to bring sections of the area out of Red Flag concerns. This will be further assessed in the coming days.

Outside of the Red Flag Warning areas, for the rest of this week conditions will still be hot, dry, windy, and unstable, with poor ridgetop and east side recoveries, and periods of near-critical conditions.

Looking ahead into the extended, there are signs that a weak dry frontal passage is possible sometime early next week. This could result in slightly cooler to near normal temperatures, but would also bring a period of increased winds, which would heighten fire weather concerns yet again. -BPN

MFR WATCHES/WARNINGS/ADVISORIES

OR...Heat Advisory until 11 PM PDT Thursday for ORZ023-024-026- 028>031.

Red Flag Warning until 9 PM PDT this evening for ORZ616-617- 620>623.

CA...Heat Advisory until 11 PM PDT Thursday for CAZ080-081-083>085.

Red Flag Warning until 9 PM PDT this evening for CAZ280-282.

PACIFIC COASTAL WATERS...Hazardous Seas Warning until 5 PM PDT this afternoon for PZZ356-376.

Small Craft Advisory until 11 AM PDT Wednesday for PZZ356-376.

Small Craft Advisory until 11 AM PDT Wednesday for PZZ350-370.