Marine Weather and Tide Forecast for Sandpoint, ID

SYNOPSIS
Winds will be breezy Monday and Tuesday afternoon across parts of central Washington. A weather system moving through Monday Night into Tuesday morning will bring rain to the region, except Cascade valleys that will be shadowed out. Warmer and drier weather returns Wednesday and Thursday. Rain returns toward next weekend.

DISCUSSION
Tonight through Tuesday Night: An upper trough swinging into British Columbia will send continued increased moisture into the region tonight into Tuesday morning as precipitable water values increase to near 180% of normal. Models continue to depict widespread precipitation developing overnight into early Tuesday, except portions of Central WA which will be in the rain shadow off the Cascades from downslope westerly flow. Rain amounts across the ID Panhandle and eastern third of WA are expected to range between a tenth to a quarter inch. The back edge of the precipitation reaches SE WA into the Central Panhandle Mountains late Tuesday morning. Drying aloft will limit the afternoon convection potential with showers confined to mainly the ID Panhandle. Clearing Tuesday Night combined with residual boundary layer moisture over the ID Panhandle and NE Washington will result in areas of fog.

Wednesday through Monday: High pressure builds in Wednesday and Thursday bringing warmer temperatures under mostly clear skies.
Friday the ridge begins to shift east, but southerly flow ahead of an upper trough will bring additional warming to the region with high temperatures in the upper 70s to low 80s. The trough then pushes in Friday Night into Saturday bringing cooler and showery conditions. The GFS, ECMWF, and Canadian ensembles are showing energy from the passing trough splitting, and thus this is not expected to be a significant precipitation producer. As the trough pushes out Sunday and Monday temperatures begin to trend upward along with a gradual decrease in precipitation chances. JW



AVIATION
06Z TAFS: Mid and high clouds have arrived with mainly virga 06-09 and with light rain developing after 12z. Central WA will see lighter amounts due to downslope off the Cascades with VFR conditions persisting. Over Eastern WA/N Idaho HRRR shows high chances for CIGS dropping to at least MVFR, with areas of IFR possible especially over the ID Panhandle and into Pullman.
Steady rains will give way to breezy winds and showers Tuesday morning.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Main uncertainty through 12-14z will be if sprinkles fall from the thickening midlevel clouds. By 14z Tuesday, HRRR shows a 50-60% chance of MVFR conditions for KGEG/KSFF/KCOE/KPUW, increasing to 70-90% by 16z. The chance for IFR conditions also increases, reaching 40% at 16z for KGEG/KCOE/KPUW. Tuesday afternoon, there is a 10-15% chance for lightning strikes with convection over north Idaho.
Future taf amendments may need to include prob30 at KCOE. /sb

-----------------------

Confidence descriptors:

Low - Less than a 30 percent chance Moderate - 30 to 70 percent chance High - Greater than a 70 percent chance

For additional probabilistic information for NWS Spokane airports,

please refer to the Aviation Dashboard on our webpage: https:/ www.weather.gov/otx/avndashboard

Preliminary Point Temps/PoPs
Spokane 47 64 40 69 42 76 / 40 80 0 0 0 0 Coeur d'Alene 45 60 37 66 40 74 / 40 100 20 0 0 0 Pullman 44 57 36 63 40 73 / 30 90 10 0 0 0 Lewiston 51 65 44 70 44 79 / 20 90 10 0 0 0 Colville 43 66 37 71 38 75 / 60 70 10 0 0 0 Sandpoint 45 58 38 65 40 73 / 50 90 30 0 0 0 Kellogg 45 54 42 62 43 72 / 40 100 30 10 0 0 Moses Lake 49 71 40 73 43 80 / 40 50 0 0 0 0 Wenatchee 51 68 44 73 48 77 / 40 10 0 0 0 0 Omak 47 71 40 74 44 78 / 30 10 0 0 0 0

OTX WATCHES/WARNINGS/ADVISORIES
WA...None.
ID...None.