HMT Forecast 2/3/2008 19:40 UTC
The current event is winding down and may end at 18UT this morning with the NAM forecast trof passage or it may have already ended according to satellite imagery. Water vapor imagery indicates that drier air was entrained over the ARB at about 09UT and may coincide with early trof passage. NAM still puts down only 0.17 inches and GFS only 0.05 inches after 12UT. Models did reasonable job considering the widespread precipitation amounts in the past 24 hours ending 8am Pacific time this morning, BLU reported 2.87 inches, Huysink 2.44, Auburn 1.00, Georgetown 1.84, and Forni Ridge 1.28 inches. NAM continues to show this to be overall a warmer event than initially forecast with freezing levels near 875 hPa. Satellite water vapor imagery has a building ridge at 46N 153W and it is amplifying driving moisture surges more N-S with time as waves traverse the east side of the ridge.
Models consistent with next moisture surge near 12UT 2/6 but it sweeps by quickly, GFS only produces 0.09 inches in ARB with this.
Next moisture opportunity is near 00UT 2/8 and GFS barely registers precip in the ARB.
Long range forecast appears to be dry after that with maybe an event near 2/13.
Dan Birkenheuer ESRL/GSD