I've been trying to wat for an optimal time to hike past the Glacier Peak area, which wshould have awesome photoops in clear weatehr. Looks like I would have to wait anotehr week. Maybe I should consider skipping this section for later, maybe even for next year, in which case the Suiattle TH would be open and I could do it much easier.
But I am getting very restless sitting here, again with a few sunny days and I'm not ready to do anything to take advantage of them. I'm inclined at the moment to push on, despite facing clouds and rain during most of the 6 days it will take me to get through this section. I really should reconsider. But again if I do that I'll need to fetch my bike back at Rainy Pass, research the specific logisticts of a Stevens to Snoqualmie or Chinook to Snoqualmie Pass loop, which will wast two upcoming sunny days. Hate such a dilemma!
Here's the current forecast,discussion, just FYI.
NATIONAL WEATHER SERVICE SEATTLE WA 900 AM PDT WED SEP 19 2014 .SYNOPSIS...A WEAK UPPER LEVEL TROUGH OVER THE AREA TODAY WILL KEEP SKIES MOSTLY CLOUDY WITH A CHANCE OF MORNING SHOWERS. CLOUDS WILL GRADUALLY DISSIPATE TONIGHT AS A STRONG UPPER LEVEL RIDGE BUILDS OVER THE PACIFIC NORTHWEST. THE STRONG RIDGE AND LOW LEVEL OFFSHORE FLOW WILL BRING SUNNY SKIES AND A WARMING TREND THIS WEEKEND. A WEAKENING FRONT ON MONDAY WILL BRING INCREASING CLOUDS...A FEW SHOWERS...AND COOLER TEMPERATURES. A LARGE UPPER LEVEL TROUGH WILL MAINTAIN A WETTER AND COOLER PATTERN ALL NEXT WEEK. && .SHORT TERM...A WEAK SURFACE TROUGH EMBEDDED IN WLY FLOW IS DISSIPATING ALONG THE N WA COAST THIS MORNING. MODELS SHOW NO REFLECTION AT THE SURFACE BY THIS AFTERNOON AND NOT MUCH UPPER LEVEL SUPPORT. RADAR DATA DOES SHOW A FEW RESIDUAL SHOWERS FROM THE N COAST EWD ACROSS THE STRAIT OF JUAN DE FUCA AND OVER THE N INTERIOR. THESE SHOWERS WILL DECREASE THIS AFTERNOON. THE REST OF THE AREA INCLUDING THE PUGET SOUND REGION SHOULD BE DRY TODAY ALTHOUGH CLOUDS WILL HANG IN THROUGH THE AFTERNOON GIVEN THE MOIST ONSHORE FLOW. HIGHS WILL AGAIN BE COOL...AROUND 70 FOR THE SOUND AND LOW 70S ACROSS THE SW INTERIOR. THE 500 MB RIDGE RAPIDLY AMPLIFIES OVER THE REGION TONIGHT THROUGH SATURDAY. LOW LEVEL NORTHERLY FLOW DEVELOPS TONIGHT...THEN BECOMES MORE STRONGLY OFFSHORE SATURDAY AS THERMALLY INDUCED LOW PRESSURE FORMS JUST OFF THE COAST. DRYING SHOULD TAKE PLACE TONIGHT IN THE MID/UPPER LEVELS. HOWEVER...A STRONG SUBSIDENCE INVERSION WILL TRAP SOME AREAS OF LOW CLOUDS AND FOG IN A THIN LAYER BELOW 2 KT ACCORDING TO NAM-BUFFER SOUNDINGS. ANY FOG/STRATUS SHOULD BURN OFF RATHER QUICKLY BY MID-LATE MORNING. WITH THE PICK UP IN OFFSHORE FLOW AND THE DRYING AIR MASS...HIGH TEMPERATURES WILL WARM A GOOD 4-10 DEGREES SATURDAY. THE COAST MAY SEE THE WARMEST TEMPERATURES GIVEN THE LOCATION OF THE THERMALLY INDUCED TROUGH AHEAD OF THE STRATUS SURGE. UPPER LEVEL HIGH PRESSURE WILL START TO SHIFT FURTHER INLAND SATURDAY NIGHT AND SUNDAY. THIS WILL ALLOW THE THERMALLY INDUCED TROUGH TO SHIFT INLAND OVER INTERIOR WRN WA. SUNDAY SHOULD THEREFORE BE THE WARMEST DAY OVER INLAND AREAS. HIGHS IN THE MID 85S WILL PROBABLY BE COMMON. THE NAM MOS SHOULD AGAIN DO BEST IN THIS SCENARIO BUT THE GUIDANCE IS STILL LIKELY HANDICAPPED A BIT BY CLIMATOLOGY. THE FORECAST IS ALREADY TRENDED 2-4 DEGREES ABOVE THE WARMEST MOS WHICH SEEMS REASONABLE. MERCER .LONG TERM...NO CHANGES FROM PREVIOUS DISCUSSION...ALL FACTORS ARE IN PLACE FOR A SW MARINE PUSH SUNDAY NIGHT. STRATUS SURGE UP THE COAST ON SUNDAY...UPPER LEVEL RIDGE AXIS SHIFTING OVER W MT...AND WEAKENING COLD FRONT APPROACHING THE COAST. THE SW MARINE PUSH SUNDAY NIGHT SHOULD PUSH STRATUS UP THROUGH AT LEAST MOST OF PUGET SOUND BY MONDAY MORNING. EARLIER NAM RUNS WERE LESS EXTENSIVE WITH THE BOUNDARY LAYER RH MONDAY MORNING...BUT THE LATEST 06Z NAM COVERS ALL OF W WA. THE NAM TIME-HEIGHT SECTION SHOWS A MARINE LAYER AROUND 4000 FEET DEEP MONDAY MORNING. IF THIS WORKS OUT THEN CLOUD COVER WILL HAVE TO BE INCREASED FOR MONDAY. THE MODELS HAVE BEEN FAIRLY CONSISTENT WITH MONDAYS APPROACHING FRONTAL SYSTEM. MODELS SHOW THE FRONT REMAINING INTACT UNTIL IT MOVES E OF 130W MONDAY MORNING. AT THAT POINT MODEL CROSS-SECTIONS SHOW THE UPPER LEVEL TROUGH SHEARING AWAY FROM THE LOW LEVEL FRONT...LEAVING IT TO STALL ALONG THE COAST. THE MODELS HAVE BEEN DRY FOR W WA ON MONDAY...BUT WITH A DEEP MARINE LAYER IT IS POSSIBLE THAT SOME DRIZZLE COULD DEVELOP MONDAY MORNING...CAUSED BY WEAK LIFT FROM THE UPPER TROUGH AS IT CONTINUES MOVING INLAND. BOTH GFS AND ECMWF HAVE A LONGWAVE UPPER LEVEL TROUGH DEVELOPING OFFSHORE OVER THE NE PACIFIC BY TUESDAY WITH SW FLOW ALOFT OVER W WA. THE TROUGH WILL DOMINATE THE PATTERN ALL NEXT WEEK FOR PERIODS OF RAIN OR SHOWERS OVER W WA. BOTH MODELS SHOW A COLD FRONT REACHING W WA TUESDAY NIGHT OR EARLY WEDNESDAY. THIS SYSTEM WILL PROBABLY SCOOP UP THE REMNANTS OF MONDAYS STALLED FRONT AS IT MOVES INLAND. KAM && .AVIATION...WESTERLY FLOW ALOFT TODAY AND TONIGHT. AN UPPER LEVEL RIDGE WILL BUILD TO THE SOUTHEAST OF THE AREA ON SATURDAY TURNING FLOW ALOFT TO THE SOUTHWEST. AT THE SURFACE...A WEAKENING FRONTAL SYSTEM OVER THE COASTAL WATERS THIS MORNING WILL DISSIPATE AS IT MOVES INLAND TODAY. SURFACE HIGH PRESSURE WILL BUILD OVER SOUTHERN BRITISH COLUMBIA ON SATURDAY GIVING INCREASING NORTHERLY FLOW AT THE LOW LEVELS. THE AIR MASS IS MOIST AND STABLE. SATELLITE IMAGERY AND PILOT REPORTS SHOW MULTIPLE CLOUD LAYERS WITH TOPS OVER 8000 FEET. FROM ABOUT KSEA SOUTHWARD IN THE INTERIOR...THE LOWER LEVELS BELOW 3000-5000 FT ARE CLEAR. MVFR CEILINGS ARE FOUND IN THE INTERIOR FROM ABOUT KSEA NORTHWARD WITH LOCAL IFR CONDITIONS OVER THE KITSAP PENINSULA. CONDITIONS N OF KHQM ALONG THE COAST ARE LOW IFR IN STRATUS...LIGHT RAIN AND FOG. CONDITIONS WILL GRADUALLY IMPROVE FROM THE SOUTH AND EAST TODAY WITH MAINLY VFR CONDITIONS EXPECTED AFTER 22Z. CEILINGS WILL BREAK THIS EVENING AS FLOW BECOMES MORE N/NE IN THE LOWER LEVELS AND THE AIR MASS DRIES SOMEWHAT. THE LATEST NAM12 SOLUTION SHOWS A LOW STRATUS AND FOG LAYER FORMING BELOW A DEVELOPING LOW LEVEL SUBSIDENCE INVERSION IN THE INTERIOR AS LOW LEVEL NORTHERLY FLOW INCREASES AND IS PRECEDED BY RADIATIONAL COOLING. THE NAM12 MOS GUIDANCE AND TIME HEIGHT SECTIONS SHOW IFR CONDITIONS THROUGH MUCH OF THE INTERIOR FROM KPAE SOUTHWARD 08Z-20Z SAT...AND LOW IFR VIS IS POSSIBLE IN LOCATIONS WHERE THE STRATUS INTERSECTS THE GROUND. THIS IS TYPICAL FOR THE EARLY FALL SEASON AS OFFSHORE FLOW DEVELOPS BEHIND A WEAKENING FRONT. THIS CHANGE WILL BE REFLECTED IN THE 18Z TERMINAL FORECASTS FOR KPAE...KSEA...KBFI AND KOLM. THIS STRATUS AND FOG IS ALSO LIKELY TO FORM IN THE CHEHALIS VALLEY AND IMPACT THE KHQM TERMINAL DURING THE LATE NIGHT AND MORNING HOURS. ALBRECHT KSEA...CEILINGS HAVE IMPROVED TO OVER 3000 FT AT THE TERMINAL AND LOWER CEILINGS ARE LIFTING NORTH OF THE TERMINAL EXPECT CIGS TO IMPROVE TO 050-060 LATE THIS MORNING WITH CLOUDS BREAKING DURING THE LATE AFTERNOON OR EVENING HOURS. AS MENTIONED ABOVE...EXPECT LOW STRATUS WITH CIGS 003-005 TO DEVELOP AROUND AND TO THE NORTH OF THE TERMINAL ABOUT 09Z AS A SUBSIDENCE INVERSION DEVELOPS OVER THE AREA AND TRAPPED LOW LEVEL MOISTURE CONDENSES WITH RADIATIONAL COOLING. THE STRATUS WILL RAPIDLY SPREAD/DEVELOP SOUTHWARD ONCE IT FORMS. THERE IS ABOUT A 50 PERCENT CHANCE THAT VISIBILITIES AT THE TERMINAL WILL DROP TO BELOW 1/2SM FG IF THE STRATUS BASES ARE SLIGHTLY LOWER THAN CURRENTLY EXPECTED. THE STRATUS WILL LIKELY BREAK UP AROUND 20Z SAT. SOUTH WINDS TODAY 4-8 KT WILL BECOME LIGHT IN THE AFTERNOON THEN BECOME NORTH 6-8 KT AFTER 05Z THROUGH SAT MORNING. ALBRECHT && .MARINE...A WEAK AND DISSIPATING FRONT OVER THE COASTAL WATERS WILL MOVE INLAND TODAY. BEHIND THE FRONT...SURFACE HIGH PRESSURE WILL DEVELOP OVER SOUTHERN BRITISH COLUMBIA AND WILL STRENGTHEN SATURDAY AND SATURDAY NIGHT. THIS WILL INCREASE LOW LEVEL NORTHERLY FLOW TONIGHT THROUGH SATURDAY NIGHT. FLOW WILL BECOME MORE EASTERLY LATE SATURDAY NIGHT INTO SUNDAY AS THE HIGH OVER BRITISH COLUMBIA MOVES SOUTHEASTWARD. SMALL CRAFT ADVISORY EAST WINDS ARE LIKELY AT THE EAST ENTRANCE TO THE STRAIT OF JUAN DE FUCA AND THE ADJACENT COASTAL ZONE LATE SATURDAY NIGHT INTO SUNDAY MORNING. A WEAKENING FRONT WILL APPROACH THE COASTAL WATERS LATE SUNDAY INTO SUNDAY NIGHT. THE APPROACH OF THE FRONT WILL LIKELY INDUCE A SOUTHERLY SURGE OVER THE COASTAL WATERS SUNDAY INTO SUNDAY NIGHT. A MUCH STRONGER FRONTAL SYSTEM WELL OFFSHORE WILL BE APPROACHING FROM THE WEST ON TUESDAY. ALBRECHT
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