textproduct: Eureka

KEY MESSAGES

- Seasonable temperatures along the coast with persistent overnight and morning coastal stratus and through mid week.

- A gradual warming trend is expected late this week and into the weekend.

SYNOPSIS

Mostly diurnal, pervasive coastal stratus will continue the pattern of low clouds, fog, and seasonal temperatures along and near the coast through Wednesday. Better chances for clearing are expected Wednesday and Thursday along the coast. Inland areas will see warm afternoon temperatures early this week before a building high pressure system ushers in hotter conditions for interior valleys by late week.

DISCUSSION

An upper level trough in the Pacific Northwest is continuing to bring onshore flow leading to coastal stratus and near normal summertime temperatures. Highs in the 90s are expected today in Trinity and Lake counties. Closer to the coast the marine layer may deepen slightly and bring some slightly cooler temperatures to near coastal areas such as Garberville and Gasquet. The immediate coast is not expected to see much if any clearing. Wednesday, the upper level trough starts to move over the area which may aid in some scattering of clouds at the coast with areas near the coast starting to see some warming.

High pressure is forecast to begin building into the area on Thursday with the flow aloft in the Pacific Northwest becoming more zonal. This is expected to warm temperatures another few degrees and help keep the marine layer mixed out.

Friday and into the weekend the ensembles are showing the upper level ridge retrograde slightly towards the west. The models are not in great agreement on how far west this will go and this will directly impact how quickly the heat will build in. Currently the forecast only has a slight warmup. This is still the potential for more warming, but is currently not looking all that hot and only slightly above seasonal normals. MKK

AVIATION

Onshore flow is expected for coastal terminals of Northwest California today. This will reinforce a rather persistent coastal stratus layer along the coast and up nearshore river valleys. This afternoon/evening, coastal stratus is expected to cling a bit more over the coastal areas with only minimal scattering/lifting of low clouds. LIFR/IFR conditions are expected again along the coast throughout tonight with some potential for for early tomorrow morning. VFR conditions are anticipated for most inland terminals throughout the TAF period. /JLW

MARINE

Northerly winds are building again this afternoon/evening. These will be strongest south of Cape Mendocino and especially in the lee of the Cape. In addition, steep wind driven waves will build through the end of the week. Also, there are a couple of small swells. Tonight and through the work week, the winds are forecast to remain in the 20 to 25 kt range in the outer waters. The inner waters are expected to increase as well, but may be less persistent and slower to increase.

EKA WATCHES/WARNINGS/ADVISORIES

CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PDT Friday for PZZ455-475.