textproduct: Eureka

KEY MESSAGES

* Another cold morning is expected this morning with areas of frost and freezing potential.

* Dry conditions will lead to areas of low relative humidities through the week.

* A warming trend is expected to impact the area through the week into the weekend, peaking on Friday.

SYNOPSIS

Clear skies and seasonable temperatures are expected today. Another chilly morning is forecast this morning with areas of Frost and Freezing potential. A warming trend will increase temperatures through the week.

DISCUSSION

Last weekend, a cold front brought cooler and dry air to the area. This system disrupted the marine layer allowing for clear skies at the coast through early this week as steady light offshore winds overnight continue. Clear skies and light wind will allow for uninterrupted cooling in the valley floors. Frost Advisories and Freeze Warnings have already been issued for many interior valleys from 1 A.M. through 8 A.M. this morning. Wednesday night should be warm enough to have much less impacts from cooler temperatures as temperatures could struggle to reach or go below 32F.

Through the week, a slight warming trend will take effect due to a building upper level ridge. This weather pattern will result in calm, chilly conditions with building winds in the afternoon as daytime heating takes effect. Inland heating is likely to peak Thursday and Friday with valleys reaching the high 80s to low 90s again. Winds will be mostly terrain driven with upslope - upvalley flow. Relative Humidities will reach a minimum late week with widespread areas of RH values <20%. however, winds ware likely to remain terrain-driven and light to moderate late week.

This coming Sunday into next Monday, Ensemble clusters show an upper level trough and an associated cold front entering the area. Both the GEFS and EPS support this as well. This system is 7days out and could change substantially through the week. Most of this system's rain would fall in the northern counties of Del Norte, Humboldt, and Trinity where some of the highest ridges above 4000ft could see very light snow whereas Mendocino and Lake counties are more likely to see moderate to strong NW winds if this system remains on track. This system is capable of changing and updates can be expected through the week. DS

AVIATION...06Z UPDATE

Northerly winds veer northeasterly and eventually more ENE overnight at KCEC. This offshore set up will keep terminals clear overnight for the most part. Similar set up at KACV overnight but more true to easterly with light winds under 5kts. Cloud cover not likely to impact flight categories until dusk hours before sunset on Tuesday. Some haze may lightly obfuscate visibility at times from area wildfires but not heavily. Northerlies return to KUKI by the early evening tomorrow, VFR otherwise. /EYS

MARINE

Winds are backing away from the coastline and easing. The hazardous seas warning was canceled early due to improving conditions Monday afternoon. Overnight it looks like small craft conditions for all area waters with both the northern and southern inner water losing the small craft advisories just before sunrise. Some lingering steep seas overnight around 11 feet in the outer waters, easing to around 7 feet this morning. Winds build back up today at 10-15kts with SC.Y lasting longer in the southern outer waters, zone pzz475.

FIRE WEATHER

Multiple days of cool but dry air has lowered ERC values. Much weaker, terrain-driven winds and an increasingly stable atmosphere in the coming days will help greatly reduce overall fire danger. However, dry conditions are expected through the week (around 20% RH each day) with worsening overnight recoveries through Thursday as midslope thermal belts develop. Smoke transport will also worsen through the week for any fires that do start. More moist air is expected to push across the area this weekend with a potential for very breezy conditions in Mendocino and Lake county late this weekend into early next week. DS

EKA WATCHES/WARNINGS/ADVISORIES

CA... Frost Advisory until 8 AM PDT this morning for CAZ103-104- 106-108>111-114-116>118.

Freeze Warning until 8 AM PDT this morning for CAZ108-110- 111-114-116-117.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 6 AM PDT early this morning for PZZ450-455.

Small Craft Advisory until noon PDT today for PZZ470.

Small Craft Advisory until 9 PM PDT this evening for PZZ475.