textproduct: Medford

DISCUSSION (Today through Sunday)

Key Points:

* Minor to Moderate impacts continue through the forecast

* Moderate impacts from heatwave through tomorrow - Temperatures upwards of 20-25 degrees above normal - Many westside valleys with highs around 100 degrees - Temperatures cool later in the week but remain above normal

* Elevated fire weather conditions through Wednesday - Fuels are the main driver limiting the critical threat - Fuels likely become more receptive Thursday onward

* Increasing signal for thunderstorms Friday/Saturday - Mainly northern California and eastside areas - Friday has the greater chance with severe weather potential

Further Details:

We continue to see an area of high pressure at 500mb over the Pacific located roughly at 130W and 40N, resulting in a dry northwesterly flow over the forecast area through tomorrow. By Wednesday, the high starts to break down and move east, and by Thursday we will see a trough emerge over the Pacific at the same time the high moves east/southeast over the Desert Southwest. In the meantime, the area of high pressure will keep highs well above normal for this time of year, and has resulted in a Heat Advisory for much of the area through tomorrow. The eastside gets into the Heat Advisory mix starting tomorrow. That said, high temperatures will remain above normal through the forecast period with only a relatively "slight" cool down Friday and through the weekend.

The open wave trough off the California coast will produce south to southwesterly flow in the upper levels over the forecast area starting as early as Thursday. This will combine with the return of moisture, and instability is expected to increase Thursday through Saturday. While we see instability increase on Thursday, the upper level dynamics may lack energy aloft to get thunderstorms going. That said, there is a chance we could see very isolated thunderstorms on Thursday with convective temperatures being reached before the trough supports better dynamics on Friday. MUCAPE values could be around 500 J/kg to upwards near 1000 J/kg on Friday. Overall, Friday has the best potential for thunderstorms (possible severe) as bulk shear values reach 20 to upwards near 30 knots (slight decrease in shear from yesterday). The CAPE/shear combination may allow for a few updrafts to maintain which could produce strong erratic gusts/downburst around 45-60mph (inverted-v sounding profiles) and hail around 0.50"-0.75". This would be in addition to the threat of lightning. On Saturday, we do see lingering instability, but the trough axis may be east of the forecast area. Can't completely rule out thunderstorms for Saturday, but the trend is for thunderstorms chances to be better east of the forecast area given the trough axis location.

-Guerrero

MARINE...Updated 200 PM PDT Monday, June 15, 2026

A dry cold front will push through the waters on Tuesday as some strong northerlies develop over the waters Tuesday afternoon through Wednesday. Gales are likely in the outer waters south of Gold Beach with some of those gales coming within 5 nm of shore. Otherwise, conditions will be hazardous to smaller crafts for all other areas as seas become steep through Thursday. The strong northerlies will weaken around the weekend as a disturbance moves through the Pacific Northwest.

-Smith

FIRE WEATHER

Updated 200 PM PDT Monday, June 15, 2026...Elevated fire weather conditions will develop this afternoon west of the Cascades. There are some areas suggesting red flag criteria around the Rogue Valley and Illinois Valley due to the dry airmass and afternoon breezes. Hot and dry conditions will persist into Tuesday before a dry cold front moves through southern Oregon Tuesday evening.

One should see overnight recoveries move notably higher, although temperatures will only drop 5 degrees from Monday night into Tuesday night. Even with this dry "cold" front, temperatures will remain quite warm with highs in the mid to upper 90's west of the Cascades through Wednesday and even Thursday.

An upper level low will develop in the Pacific by Thursday and ensembles are suggesting a low chance of thunderstorms around the Oregon/California border on Thursday afternoon.

As the upper level low moves closer to the coast on Friday, the chance of showers and thunderstorms increases mainly east of the Cascades. Almost all the ECMWF members were showing showers and thunderstorms in our CWA Friday afternoon. 0-6km shear shows southerly storm motion at 20 knots with precipitable water values around 0.9 inches. Therefore, the threat of dry thunderstorms seems valid with some inverted V forecast soundings.

-Smith

MFR WATCHES/WARNINGS/ADVISORIES

OR...Heat Advisory until 11 PM PDT Tuesday for ORZ021-023>026-029.

CA...Heat Advisory until 11 PM PDT Tuesday for CAZ080>085.

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 PM PDT Tuesday for PZZ350-356-370-376.

Gale Warning from 5 PM Tuesday to 2 AM PDT Thursday for PZZ356- 376.