PREV DISCUSSION
/Issued 913 AM PDT Fri Sep 20 2024/

DISCUSSION...An update is not necessary. Our weather will be quiet, with cooler temperatures today behind yesterday's passage of a dry front. The one exception will be warmer temperatures at Brookings (expected to reach the lower 80s) with downslope warming of easterly winds. The warm temperatures at Brookings are expected through the weekend. Seasonable temperatures will continue for the remainder of the coast. Otherwise and elsewhere, a warming trend will begin Saturday and continue into Tuesday.

A trough next Wednesday should start a parade of seasonably weak fronts with at least modest cooling, but little if any chance of rain. -DW

AVIATION
20/12Z TAFS
VFR conditions will prevail across the area for the next 24 hours, with gusty north winds expected along the coast through the afternoon and evening.

The exception will be areas of patchy marine stratus along the coast north of Cape Blanco and in the vicinity of Brookings, where MVFR/IFR conditions are possible through the morning. -BPN

MARINE
Updated 800 AM Friday, September 20, 2024
A thermal trough pattern will likely persist through early next week. This will result in the strongest northerly winds south of Port Orford during the afternoon and evening hours, with very steep seas and occasional gale gusts at least into Saturday evening. Meantime, steep seas and advisory strength northerly winds are expected north of Port Orford.

The thermal trough is forecast to move inland with weakening winds and easing seas late Tuesday into Wednesday. -Spilde/Hermansen

PREV DISCUSSION... /Issued 249 AM PDT Fri Sep 20 2024/

DISCUSSION...Overall quiet conditions are expected over the next several days, with upper level ridging overhead, a thermal trough along the coast, and with a few exceptions, generally seasonable weather across the region. With the ridge in control, the area will remain dry until the mid-to-late next week, when the next front may pass through the area.

Along the immediate coast, the thermal trough will continue to produce gusty north winds, with occasional periods of fog and/or low clouds as the marine layer make periodic inland pushes. These clouds and fog will stay west of the coastal mountains, however,r as the thermal trough will also result in a general dry, east wind flow that will scour out much of the moisture and keep the marine layer at bay. This same wind is likely to produce an ongoing Chetco Effect as well, keeping temperatures warmer than normal along the south coast near Brookings,

Inland, temperatures will remain around or just above normal for this time of year, which means the first day of Fall on Sunday will feel like a typical day in mid-September. Fall will not arrive for good, however, when temperatures jump back up to summertime values Tuesday and Wednesday as the upper level ridge axis amplifies and passes overhead, making those days feel more like late July or early August.

As mentioned above, this dry pattern may change a bit with the arrival of a front around Thursday. This system appears pretty weak in the latest models suites, with little in the way of moisture content, and with much of the energy well to our north.
So, other than some light rain possible along the coast and into the Umpqua Basin, the passage of this system looks like it will do little more than bring temperatures back down to more seasonable values as we head into next weekend. -BPN

FIRE WEATHER
Issued 245 AM Friday, September 20, 2024
Pretty quiet weather will continue into this weekend as the flow remains progressive out of the north west. A Weak disturbance moves through the Pacific Northwest around Saturday before a stronger wave moves through the state of Washington around Sunday.

The end result should be a notable north east to south west pressure gradient with some stronger north east winds(15 to 20 knots), especially over the Kalmiopsis wilderness. Looking at some ensemble data and comparing to the climatology to this time of year, nothing jumps out as extreme. There could also be some light east breezes instead of stronger north east winds depending on what ensemble cluster comes to fruition around Monday night. In any case, Monday night is a period to keep an eye on, especially for the fire weather conditions in the extremed southwest Oregon.

-Smith

MFR WATCHES/WARNINGS/ADVISORIES
OR
CA
None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT Saturday for PZZ350-356-370-376.

Hazardous Seas Warning until 11 PM PDT Saturday for PZZ356-376.