textproduct: Medford

Updated AVIATION Discussion

AVIATION...16/12Z TAFs

Aside from some high clouds streaming over the area, little change is expected to VFR flight levels in this TAF period. Gusty north winds (20-30 kt) are expected to return to the coast today while other areas will see typical diurnal breezes. Patches of IFR stratus are possible at the coast north of Cape Blanco this afternoon, between 18-21z, with potentially more coverage overnight tonight.

PREV DISCUSSION

/Issued 254 AM PDT Tue Jun 16 2026/

KEY POINTS...

* Hot temperatures continue today, with Heat Advisory in effect until tonight. Temperatures trend somewhat cooler on Wednesday with a more noticeable cool down Friday into the weekend.

* Elevated fire weather concerns Thursday -- dry and unstable conditions.

* Increasing signal for thunderstorms for latter half of week, possibly as early as Thursday, but most likely on Friday. Focus for activity expected over northern California and east of the Cascades.

DISCUSSION...Fairly quiet morning with satellite imagery only showing some high level clouds streaming over the region. It'll be another hot day across the region, though the heat wave will begin to ebb for areas west of the Cascades today, most notable along the coast north of Cape Blanco and into the Umpqua Basin. The upper level pattern responsible for this heat features a strong high pressure just offshore over the eastern Pacific, that will weaken and expand eastward today, eventually settling into the Great Basin region by Thursday. Meanwhile, weak energy will linger off the coast of California and meander westward around this high pressure while it expands/shifts eastward. This energy comes into play for the latter half of the week. In the meantime, a Heat Advisory remains in effect through this evening due to a moderate risk of heat related illnesses. Be sure to take precautions to protect yourself from the heat. If you plan to seek relief in area waterways, please remember that the water is still quite cold, and cold water shock is a real thing. Temperatures do trend cooler for the latter half of the week, but will remain above normal (mid-upper 90s West/upper 80s-low 90s East) until the weekend. So instead of being 15-25 degrees above normal like yesterday, it'll "cool" to only 10-15 degrees above normal.

The upper level pattern shifts on Thursday. That meandering weak energy combines with a few other weak shortwaves passing through in the westerlies and carves out a weak open trough over the eastern Pacific by Thursday afternoon. Temperatures tick upward a few degrees on Thursday under southerly flow, and it's possible we see another triple degree day here in Medford on Thursday. The larger concern however, is the thunderstorm potential that comes with this pattern transition. It's almost a guarantee that heat waves conclude with a thunder threat, and it seems this event is no different. Moisture and instability increase on Thursday, and there are some weak shortwaves passing through, but moisture is pretty marginal on Thursday. It's more likely that there will be some cumulus buildups with a stray shower across northern California. By Friday, however, the trough nudges closer and moisture looks more favorable for thunderstorms. Currently, it looks like the focus would be across northern California and east of the Cascades, but model guidance shows some potential convection over the Siskiyous, which could bring some storms into southeastern Jackson County. We'll keep an eye on model trends to see if thunderstorm chances expand westward with time.

The trough axis moves through the region Friday night, taking the moisture and instability east of our region for Saturday. It's possible some isolated activity lingers across far eastern Lake/Modoc counties early Saturday afternoon. The coolest temperatures of the forecast period are expected over the weekend as this trough passes through. Afternoon highs will still be above normal, but only on the level of 5-10 degrees.

MARINE...Updated 100 AM PDT Tuesday, June 16, 2026...A thermal trough pattern will persist through Thursday. Conditions will worsen this afternoon as northerly winds strengthen, reaching gales south of Cape Blanco and seas become very steep and hazardous. Very steep seas could spread north of Cape Blanco around mid-week, but the worst conditions are expected south of Cape Blanco. Conditions could improve late Thursday into Friday as the thermal trough pattern weakens, but steep seas are likely to persist into the weekend.

FIRE WEATHER...Updated 200 AM PDT Tuesday, June 16, 2026...The heatwave will begin to ebb today for areas west of the Cascades, most notable along the coast north of Cape Blanco and into the Umpqua Basin. Meanwhile, temperatures remain hot east of the Cascades and across northern California. With the moderating temperatures west of the Cascades, conditions will be less critical today, but it will still be dry and breezy this afternoon.

A weak marine push will bring improving recoveries tonight compared to recent days, but this improvement will be shortlived. The thermal trough will remain along the coast through Wednesday, then push inland on Thursday. This will maintain broad north through east flow across the midslopes/ridges, and poor recoveries are expected again Wednesday night. As the thermal trough shifts inland Thursday, expect another uptick in temperatures across the region. Additionally, this pattern will bring dry and unstable conditions across northern California and east of the Cascades.

Meanwhile, an open trough develops offshore over the eastern Pacific on Thursday, moving inland late Friday and east of the region on Saturday. This pattern sets up the potential for thunderstorms during this time frame, focused across northern California and east of the Cascades. Chances for thunderstorms are highest on Friday, but could begin as early as Thursday. Moisture remains fairly marginal for Thursday, but instability is present. Could just be some cumulus buildups with a stray shower or even an isolated thunderstorm in the afternoon. As the upper level low moves closer to the coast on Friday, the chance of showers and thunderstorms increases. Current guidance maintains the best chances across northern California and east of the Cascades, but there is the potential for as far west as Jackson County. By Saturday, the best moisture/instability shifts east, leaving some lingering chances along/east of the Warners/Winter Ridge.

MFR WATCHES/WARNINGS/ADVISORIES

OR...Heat Advisory until 11 PM PDT this evening for ORZ024-026-029.

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 AM PDT this morning for PZZ350-356-370-376.

Gale Warning from 11 AM this morning to 2 AM PDT Thursday for PZZ356-376.