Tonight through Wednesday...Very deep cyclone off the PAC NW coast with associated cold front draped across NRN CA attm. The front is not expected to make very much southward progress tonight and is forecast to remain north of Merced county. Plenty of clouds this afternoon will gradually clear out as a weak upper ridge is forecast to build across the region through Wednesday with a warming and drying trend.
Thursday through Saturday...Models continue to have some difficulty agreeing when the precipitation will move into the area. The GFS is around 12 hours slower than the ECM. The ECM is bringing the precip into the western edge of the CWA around noon Thursday and the GFS is around midnight Friday. The track of the storm is nearly identical as both agree that Friday will be a rainy day across the central CA interior. Snow levels are expected to be high, around 10k-11k feet, due to the origin of the system being sub tropical. The other interesting feature concerning the system is the NE trajectory. If the midweek ridge holds in too long and shunts the track of the low farther to the west, then qpf amounts will be less. The track has been consistent in the forecast and this is good. Really difficult to pinpoint any rain amounts yet, as the ECM and GFS are different in their solutions about QPF as well as timing. Clearing will be gradual on Saturday as unsettled weather is once again approaching from the west directly behind this storm.
Sunday through Monday...Another storm system with more of a colder origin from the Gulf of AK will move into the region on Sunday. The models are in decent agreement with the timing and track, as this system will be a quick moving system and looks to be east of the CWA by Monday with drier and cooler airmass behind it on Monday. Current forecast data indicates that the bulk of the precip will be north of Kern county, with Merced county getting the wettest. However, it is too far out to tell how much precip will fall.