textproduct: Eureka

.Tuesday through Wednesday

.Wednesday night through the weekend

The upper level trough off the coast starts to deepen again and then start to become a cutoff low. The models differ on how deep it gets and the location of it. But some of the models show the low bombing out. This has the potential to bring strong winds once again. It looks like stalls out off the coast around 12Z Thursday and then starts to fill. The big question is where exactly this low stalls out and where it goes when it does stall out. The winds are expected to peak Thursday morning, but could remain strong through the day Thursday and possibly into Friday. The precip amounts look lower Wednesday night through Friday morning, especially in the north.

Rainfall amounts again look heavier in the south. IVT values are lower with this system, but may last longer. They range from around 250 to 500 kg/m/s, lowest in the north.

Cold air moving in from the deep trough could support lower snow levels and greater instability. Snow levels may drop further to 3500- 4000 ft. The cold air aloft could support small hail showers and isolated thunderstorms along the coastal areas Thursday and Friday. Total snow amounts of 2-3 ft through Friday is possible at Scott Mountain pass, while up to a foot is possible above at the highest passes of Highway 36 (around 4000 ft), depending on how much the snow levels lower. This colder air aloft will also bring the potential for thunderstorms and possibly some small hail near the coast through the day Thursday.

Friday the models are in general agreement that the low will start to move out of the area. High pressure is expected to start to move into the area bringing a break in the rain and wind for the weekend. The valleys will likely see widespread fog and low clouds each night and through at least the morning. MKK/JB

DISCUSSION

Light offshore winds maintained VFR over the coastal terminals early Tuesday morning. Light rainfall spreading in from the south will bring an increasing chance for MFVR CIGs today. The wind protected inland valleys have the highest chance for IFR to LIFR conditions through early Tuesday afternoon, such as UKI. Some inland valley fog is also expected.

Moderate to heavy rainfall rates will spread over N CA late this afternoon through Wednesday morning and will reduce CIGs and VIS to more solidly MFR to periods of IFR.

A developing "bomb" cyclone will bring very strong winds aloft and to the surface. 925 mb winds near 2000 ft AGL will likely range from 65 kts to over 80 kts later this afternoon through Wednesday morning. This will bring a high end turbulence and low level wind shear threat. There is some uncertainty with the exact track and timing of these winds and associated heavy rainfall from this rather compact and very deep area of low pressure as it tracks in from the southwest.

Conditions will only very briefly improve Wednesday morning before another strong system arrives Wednesday afternoon. JJW

MARINE

Gale and storm force winds are forecast Tuesday night into early Wednesday as a compact low accelerates northeastward across the waters. Some of the models are showing winds as strong as 50 kt sustained winds at the surface. These winds will be relatively shortlived with this fast moving compact low pressure that may reach bomb cyclone statues over the waters. Wednesday a swell is expected to move in behind the winds. Waves are expected to build to 10 feet at 10 seconds.

Another powerful storm is forecast to bring strong winds and large steep waves Wednesday night. This storm may nearly reach bomb cyclone status as well and may bring more storm force winds. This one is expected to gradually weaken as it stalls out bringing an extended period of strong to gale force winds through Thursday night. Friday winds are expected to remain elevated then diminish for the weekend. MKK

HYDROLOGY

The next rounds of rain are likely to produce flooding impacts again across the area. While most ensemble members show the heaviest rain heading to Mendocino and Lake Counties again, significant rain is still likely for the entire area. Small stream, creeks, and main stem rivers are all likely to see impacts again. It is also possible the focus of the heavier rainfall will shift north again. Currently the Russian River at Hopland the Navarro river at Navarro are expected to reach flood stage again. The Eel river and the Mad river are expected to be close to flood stage, but not expected to exceed it at this time. This will need to be monitored closely.

There is a short break in the rain Wednesday before the next system Wednesday night. The break might only be 8 to 12 hours in some areas. The rainfall amounts look lower with this system, but with the ground saturated, any additional rain could be impactful given there is little time for basins to drain. MKK

EKA WATCHES/WARNINGS/ADVISORIES

CA... Flood Watch through Friday evening for CAZ101>115.

High Wind Warning from midnight Tuesday night to 9 AM PST Wednesday for CAZ101-103.

High Wind Warning from 10 PM Tuesday to 10 AM PST Wednesday for CAZ102-105.

High Wind Warning from 7 PM Tuesday to 8 AM PST Wednesday for CAZ104-106.

Wind Advisory from midnight Tuesday night to 10 AM PST Wednesday for CAZ107-108.

Winter Storm Watch from Wednesday afternoon through Friday evening for CAZ107-108.

High Wind Warning from 7 PM Tuesday to 6 AM PST Wednesday for CAZ109>115.

NORTHWEST CALIFORNIA COASTAL WATERS... Gale Warning from 2 AM to 8 AM PST Wednesday for PZZ450.

Small Craft Advisory from 1 PM to 6 PM PST Tuesday for PZZ455-475.

Gale Warning from 6 PM to 10 PM PST Tuesday for PZZ455-475.

Storm Warning from 10 PM Tuesday to 6 AM PST Wednesday for PZZ455-475.

Small Craft Advisory from 6 AM to 4 PM PST Tuesday for PZZ470.

Gale Warning from 10 PM Tuesday to 10 AM PST Wednesday for PZZ470.