By Rod Hill on 2012-01-18
I am writing this letter as the coast reports 100 mph winds. It reminds me that people often say - wow, your job is so easy, all you have to say is rain and more rain. Actually, this time of year on a daily basis, forecasters study wind threats at the coast, snow levels in the Cascades and recently on the low levels. Will the gorge play a factor in the weather? How much rain will fall, what is the temperature going to be and on and on and on! Lets say a storm episode over several days from the coast to the Cascades has 10 important elements that a forecaster is tracking. Often, 8 or 9 parts of the entire forecast is nearly exactly correct! Of course, like anything, it is the 1-2 items that people remember and poke fun and anger at.
Here is my record for the past few days overall.
1. Coast to see one it's largest wind storms of the past two years, with winds reaching 100 mph. (this verified about an hour ago)
2. Cascades to see feet of snow (okay - that was easy LOL)
3. Days of areas below 500 feet seeing a mix of rain and snow. Portland metro staying wet, not snowy - despite computer models that showed daily accumulations! (good forecast until last evening!)
4. Daily accumulations of 1-3" possible in the high metro hills. (not a bad forecast, although a couple of 12 hour periods had more like 4" +)
5. Tuesday evening: I said, Salem was in the warm sector and would stay near 40 with rain all night. (this was a good call)
6. Tuesday evening: I continued what I has said all along, Portland & low elevations would stay above freezing and not see any widespread accumulation. ( Okay - I Get an "F" on this one. After days of good forecasting, I blew the two-minute drill and lost the game.)
7. Portland would wake up to temperatures 36-39 degrees, with steady rain falling. ( A Few cold pockets remained, but this was an "A+")
So after days of working, I missed the most important 6 hour period of the entire forecast sequence. It should be noted, the one forecast model I often trust - had been way too wet and two cold for days. However, the temperature profile of the NAM model as exactly right last night and this morning. Many forecasters, I know for a fact predicted last night perfectly, but were not so great in the previous days - however, like my old drama teacher used to say.....nail the opening and the finally, no one remembers the middle. She is likely correct.
Looking back at last night, I am guilty of trying to be too perfect instead of simply saying......I am not sure, but snow will remain possible until early morning. What killed my forecast was a period of light to north winds, north of Woodburn. I expected breezes last night, which would have likely held the temperature up. As for now time to roll up the sleeves and earn trust for the next time.
Two last points. Always take note when the forecaster says there is lots of moisture available, that mean lots of things can happen. Remember, no one that I know of delivers a perfect forecast time and time again. You should expect the forecast during a storm event to be "mostly right". The trick is being ready for the couple of things that turn out to be bad information. (like last night)
As always, thank you for using my forecast,
Rod Hill
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By Rod Hill on 2012-01-16
This is your head's up, that a large area of Pacific moisture will bring heavy rain, strong winds and heavy snow to our area late Tuesday - Wednesday. Below are the Headlines I am tracking:
1. High Winds At The Coast: Peak gusts starting early Wednesday may reach 100 mph. Gusty winds, over 50 mph may continue much of the day. A 2nd period of high winds will be possible Friday.
2. Possible Snow Storm In The Gorge: There is a likely chance that temperatures will be below freezing Tuesday night and Wednesday morning. If so, the Gorge could easily get a foot of snow, with heavy accumulation making travel on I-84 difficult. An icy mix will be possible. The snow level will sharply rise Wednesday afternoon or early evening.
3. Portland - Salem metro area: The forecast snow level is uncertain. There is reason to believe, we will see heavy snow late Tuesday & into Wednesday at all elevations, so please keep updated for possible winter storm conditions. With that said, I believe the following is most likely: Tuesday morning will see a mix of rain & snow showers below 500 feet. Above, 500 feet, snow accumulation will be possible during the day, as moisture increases. Moisture will become steady Tuesday night. Areas below 500' will remain above freezing with mostly rain. Hills above 500' could see snow & ice accumulation of 3-8". Wednesday will see warm air eventually arrive with snow levels jumping to 2,000', but the timing is uncertain. So, if you live above 500', please be prepared for winter storm conditions Tuesday evening - Wednesday afternoon.
Once again, the valley forecast is uncertain, please keep updated for changing conditions. If you live above 500 feet, you may see heavy snow accumulations. If the snow level rises quickly enough, all hills near and under 1,000' would only see a few inches before rain dominates.
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By Rod Hill on 2012-01-14
Here is what I have learned, from west wind snow events, since my Portland arrival in 1999.
The following should be expected Saturday overnight - Early Tuesday. After that, the snow levels will sharply rise.
1. Areas below 500 feet: A mix of rain and snow with temperatures near and above freezing. 1" snow spots will be possible. The city center of Portland will remain mostly wet. The best chance for icy roads & snow cover at the lowest elevations will be early Monday.
2. Near & above 500 feet: Better chance of all snow. Daily snow accumulations of 1-3" will be possible.
3. 1,000 feet: Freezing temperatures and snow will be likely through the period. This is the real "WILD CARD" of the forecast. Sometimes with a westerly flow, the hills warm at times and the snow melts. Other times, the air stays cold and heavy snow stacks up! My best guess this time if for daily accumulations of 2-5" of snow.
4. Coast Range: 4-8" of snow Sunday & again Monday. Chains should be carried. All passes will see snow cover.
5. Cascades: 6-12" of snow Sunday & again Monday. Snow accumulation should be expected outside of Gresham, the whole way up the mountain.
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By Rod Hill on 2012-01-13
A Reminder, My Snow Level Forecast Is Posted on The Ski Forecast Page. Check Daily For Updates.
Air behind Saturday's cold front will drop the snow level to 1,500' by Saturday evening, near 300 feet @ times Sunday & Monday. The snow level will rise to 2,000' Tuesday afternoon.
A westerly flow Saturday night - Tuesday morning will likely mean mostly rain below 500 feet, with roadways wet & fine most hours. There will be a decent chance of occasional snow dustings at 300 feet. The best chance for an inch of snow in the Portland City Center will be Monday morning, but odds favor wet roadways & few problems.
The biggest mystery will be metro hills near and above 500 feet. Sometimes, the westerly flow brings a mix of rain and snow and other times, the hills get hammered with heavy snow. This is a total wild card! If the air is cold enough, the high hills could see 6-12" of snow through Tuesday morning. We will have to wait and see.
I do expect heavy snow accumulation of more than a foot over the Coast Range. Sandy & high hills, especially in Clark & Cowlitz counties could also see a foot of snow through the period.
Rod Hill
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By Rod Hill on 2011-12-30
Now that we have passed the half-way point through December, it is time to look at what could be the driest December in the record books, dating back to 1871! As of Dec. 16th, PDX has received .06" of rainfall. The December average is 5.71" and typically the wettest month of the year. Current forecast charts on this date give Portland at most an additional .50" of rain for the month. If true, PDX would shatter the all time December dry record!
Here are the driest Decembers on record for Portland, dating back to 1871:
1. .88" - 1876
2. 1.38" - 1976 (an El Nino year, this year is La Nina)
3. 1.90" - 1944
4. 2.19" - 1985
5. 2.37" - 1988
6. 2.40" - 1990
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To date, Portland has also seen below normal daily temperatures each day. The current mean temperature is 36 degrees. Although quite chilly, not cold enough to crack into the top 5 list of coldest Decembers.
Coldest Decembers at PDX (dating back to 1941):
1. 33.0 degrees - 1985 (Neutral)
2. 34.7 degrees - 1990
3. 35.3 degrees - 1978
4. 35.6 degrees - 2009 (El Nino)
5. 36.4 degrees - 1983
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Interesting that none of the coldest Decembers, occurred in La Nina years, in fact all but one were neutral seasons.
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By Rod Hill on 2011-12-20
Winter Solstice 2011
Winter officially begins on Wednesday, December 21 at 9:30 p.m. in the Pacific Time Zone. At that moment the sun, in the constellation of Sagittarius, sits over the Tropic of Capricorn at latitude of 23.5 degrees south. This date is the Winter Solstice, the day on which the Earth's northern pole is tipped away from the sun.
As seen from Portland, the sun will reach its lowest southern point in the sky at 21 & ½ degrees on the horizon. Because of the low angle of the sun's arc, it will produce the longest and most spectacular sunrises and sunsets of the year. On December 18-21, we will have nearly 8.5 hours of daylight to enjoy.
On the day of the winter solstice, the sun will be directly over the Tropic of Capricorn at noon and at the same time, the region above the Arctic Circle will be in total darkness for 24 hours! Incidentally, the Tropic of Capricorn is so named because a few thousand years ago the sun resided among the stars of the constellation Capricornus on the solstice date. The word solstice is derived from the Latin sol-stitium, for sun-standing. The winter solstice is the time of the year when the sun stops its southern climb and stands briefly before turning back toward the equator.
On the winter solstice the Sun from our Earth perspective appears to stand still. This was of great concern to our ancestors because they believed that all heavenly objects were gods and that if the Sun god was displeased, it might just continue to keep rising and setting farther south until it eventually disappeared. The day of the winter solstice was met with great anticipation, a bit of anxiety and a lot of celebration. Right after the solstice the Sun invariably started rising and setting a little bit farther north each day. Our ancestors interpreted the sun's rising to mean that the world would not be plunged into eternal winter and that spring would once again eventually come.
It is easy to see why our ancestors could be frightened by the sun's movements. They believed that if the Sun continued its journey south, the world would be plunged into eternal night. In fact, winter solstice celebrations were so widespread in our western culture that the early Christian church decided to move Christmas to the time of the solstice. For those of you who dislike the dark winter days, look at the bright side: after December 21, the days will gradually grow longer and the night shorter as Earth completes its yearly journey around the sun.
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The above is courtesy of Mr. Jim Todd, OMSI Planetarium Manager
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By Rod Hill on 2011-12-09
Watch the Moon Fade away
During the morning of December 10, 2011, the Full Moon will slide through the dark shadow of our planet. For 51 minutes, the only light hitting the moon will be the reddish glow from all of Earth's sunrises and sunsets - a Total Lunar Eclipse!
The moon will be situated in the constellation Taurus and near the most northerly point in the moon’s orbit at that time of the year. The circle is the earth shadow called the umbra.
For the Pacific Northwest viewers, the penumbral eclipse begins at 3:33 a.m. PST and the umbral shadow takes a small, dark bite out of the left edge of the moon starts at 4:45 a.m. PST. For 66 minutes of the partial phase, the darkness engulfs more of the moon's disk as it slides into the shadow. The partial eclipse ends and totality begins at 6:06 a.m. PST and the point of the greatest eclipse occurs at 6:31 a.m. PST. The eclipse’s total phase will lasts for 51 minutes. The moon will be only 6.5 degrees above the north western horizon at the instant of the greatest eclipse.
What makes it so much fun is that no one can predict what color the moon will turn during totality. Will it be bright orange, or blood red? Only the shadow knows. The total eclipse will end at 6:57 a.m. PST as the moon exits the umbra. Then the moon will set at 7:45 a.m. PST
A lunar eclipse happens when the Moon passes through the Earth's shadow. Earth always has a shadow, which is created by the Sun. On those rare occasions when the Moon, Earth and the Sun are all lined up just right, the Moon passes through this shadow. This would happen every full moon if the Moon orbited around the Earth in the same plane as the Earth orbits around the Sun. The Moons orbit, however, is tilted about 5 degrees above the Earth-Sun plane. This tilt itself, however, rotates, allowing eclipses to happen when the tilt of this plane lines up with the Earth-Sun plane, blocking sunlight. For future visitors to the moon, the Earth during a total lunar eclipse would appear dark and surrounded by a glowing red ring.
Unlike solar eclipses in which the sun's rays can damage the eyes, lunar eclipses are safe to watch with the naked eye. Binoculars and telescopes will enhance the view.
The most important factor will be having clear sky on Saturday morning to view the eclipse!
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Saturday morning skies should be clear with foggy pockets. Hope for the best!
The above report is courtesy of Mr. Jim Todd, OMSI Planetarium Manager
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By Rod Hill on 2011-12-06
Our dry start to the month of December, although not unusual, got me to thinking about which has been more wet the last 5 seasons, winter or spring?
I grouped the data two sets: November - February and March through June.
Nov. - Feb. total precipitation 2006 - 2010: Average 19.19" (normal 20.57")
March - June total precipitation 2007 - 2011: Average 11.50" (normal 10.32")
Conclusion: The winter months are much wetter, but slightly below normal, while the spring months have seen above normal precipitation.
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Here is where it gets interesting. Take a look at the number of days with .01" of precipitation or more over the past three seasons:
Nov. - Feb. wet days 2008 - 2010: Average 71 days (normal 70 days)
March - June wet days 2009 - 2011: Average 71 days (normal 54 days)
Conclusion: Wow! The average number of wet days are the same! Although the winter months in terms of climatology, average more than two additional weeks of wet weather.
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I began this little project because, lately it seems our winter months have not been all that wet, but our spring months have been all out soakers! The data above suggests a recent trend of drier winters and wetter springs when compared to 30 year averages.
To me, it is AMAZING that over the past three years, we have seen the same number of rainy days in spring as winter! No wonder the past spring seasons have seemed a little ridiculous!
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Please realize, I looked at a very small data set. To make any assumptions or lasting conclusions based on 3-5 years of weather records would be foolish. However, the above findings are interesting. I will be watching for similar trends this winter & spring.
Rod Hill
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By Rod Hill on 2011-11-23
A STRONG FRONTAL SYSTEM BROUGHT STRONG...DAMAGING WINDS TO NORTHWEST OREGON AND SOUTHWEST WASHINGTON TUESDAY AND WEDNESDAY. THE FIRST ROUND OF STRONG WINDS ARRIVED EARLY TUESDAY MORNING. THEN WINDS RELAXED A BIT AS THE FRONT PUSHED INTO THE REGION. TUESDAY AFTERNOON THE FRONT LIFTED BACK TO THE NORTH...WITH ANOTHER ROUND OF STRONG SOUTH WINDS RESULTING TUESDAY NIGHT AND WEDNESDAY MORNING. THIS STORM ALSO BROUGHT VERY HEAVY RAIN TO THE AREA....WHICH PRODUCED SOME LOCALIZED RIVER AND STREET FLOODING. LISTED BELOW ARE SOME WIND AND RAIN REPORTS AS OF 10 AM WEDNESDAY. -------------------------------------------------------------------- PEAK WIND GUSTS FOR TWO TIME PERIODS... FIRST ROUND TUESDAY THROUGH 815 PM SECOND ROUND BETWEEN 815 PM TUESDAY AND 615 AM WEDNESDAY -------------------------------------------------------------------- LOCATION FIRST ROUND SECOND ROUND PEAK GUST TIME PST PEAK GUST TIME PST --------------------------------------------------------------------- SOUTH WASHINGTON COAST... CAPE DISAPPOINTMENT.......66 MPH 415 PM 11/22 75 130 AM 11/23 TOKE POINT NEAR RAYMOND...43 612 PM 11/22 63 1218 AM 11/23 OCEAN PARK................58 500 AM 11/22 48 915 PM 11/22 LONG BEACH................40 426 PM 11/22 51 116 AM 11/23 NORTH OREGON COAST... ASTORIA...................81 MPH 248 AM 11/22 56 200 AM 11/23 PACIFIC CITY..............79 739 PM 11/22 74 233 AM 11/23 CAPE MEARES...............74 623 PM 11/22 92 338 AM 11/23 GARIBALDI.................69 1236 AM 11/22 81 300 AM 11/23 CLATSOP SPIT..............64 700 PM 11/22 69 1015 PM 11/22 ASTORIA AIRPORT...........61 413 PM 11/22 64 1155 PM 11/22 TILLAMOOK (CITY)..........60 738 AM 11/22 53 244 AM 11/23 SEASIDE...................60 803 PM 11/22 CANNON BEACH..............62 507 PM 11/22 TILLAMOOK AIRPORT.........54 155 AM 11/22 55 355 AM 11/23 OCEANSIDE................. 55 1044 PM 11/22 TIERRA DEL MAR............ 58 1129 PM 11/22 CENTRAL OREGON COAST... SEA LION CAVES............81 MPH 258 AM 11/22 FLORENCE SIUSLAW JETTY....76 140 AM 11/22 LINCOLN CITY..............75 630 PM 11/22 76 951 PM 11/22 CAPE FOULWEATHER..........74 450 PM 11/22 NEWPORT (YAQUINA BRIDGE)..68 625 AM 11/22 71 439 AM 11/23 YACHATS...................67 1220 PM 11/22 47 436 AM 11/23 CAPE FOULWEATHER..........66 732 AM 11/22 66 1037 PM 11/22 NEWPORT JETTY (C-MAN).....64 800 PM 11/22 51 200 AM 11/23 NEWPORT AIRPORT...........59 715 AM 11/22 53 155 AM 11/23 DUNES.....................53 804 AM 11/22 GLENEDEN BEACH............66 853 AM 11/22 COAST RANGE... MT. HEBO OREGON...........97 MPH 427 AM 11/22 85 1234 AM 11/23 ROCKHOUSE RAWS............74 912 AM 11/22 57 612 AM 11/23 JEWELL OREGON.............67 414 AM 11/22 ROCKHOUSE RAWS............64 712 AM 11/22 CEDAR CREEK RAWS..........55 710 AM 11/22 50 1110 PM 11/22 INTERIOR LOWLANDS... MCMINNVILLE AIRPORT.......45 MPH 718 PM 11/22 SALEM AIRPORT.............40 900 AM 11/22 MCMINNVILLE AIRPORT.......40 619 PM 11/22 FOREST GROVE..............40 730 PM 11/22 AURORA AIRPORT............39 900 AM 11/22 EUGENE AIRPORT............36 327 PM 11/22 PORTLAND AIRPORT..........35 845 AM 11/22 VANCOUVER AIRPORT.........32 557 PM 11/22 KELSO AIRPORT.............30 635 PM 11/22 *WIND SPEEDS REPORTED IN MPH______________________________________________________STORM TOTAL RAINFALL REPORTS AS OF 10 AM WEDNESDAY (BEGINNING 6 AM MONDAY) -------------------------------------------------------------------- LOCATION RAIN (IN) DURATION ------------------------------------------------- JUNE LAKE,WA...............10.10 SHEEP CANYON, WA...........9.10 CEDAR, OR..................8.65 FOSS, OR...................8.06 SOUTH FORK, OR.............7.63 SPENCER MEADOWS, WA........7.60 LEES CAMP, OR..............7.50 LONE PINE, WA..............7.40 COUGAR, WA.................7.24 SPIRIT LAKE, WA............6.50 GRANDE RONDE, OR...........6.30 SURPRISE LAKE, WA..........6.00 LOG CREEK, OR..............5.76 SEINE CREEK, WA............5.70 MILLER WOODS, OR...........5.70 TILLAMOOK..................5.69 SADDLE MOUNTAIN, OR....... 5.50 RYE MOUNTAIN, OR...........5.36 TILLAMOOK RAWS, OR.........5.35 ROCKHOUSE, OR..............5.34 BEAVER, OR.................5.31 NORTH FORK, OR.............5.10 TROUT LAKE, OR.............5.07 JEWELL, OR.................5.00 VERNONIA, OR...............4.93 HORSE CREEK, OR............4.87 SCAPPOOSE, OR..............4.60 FOREST GROVE, OR...........4.49 GASTON, OR.................4.46 SCOGGINS DAM, OR...........4.35 CANNIBAL RAWS, OR..........4.25 CLEAR CREEK NEAR COUGAR, WA4.22 FRANCES, WA................4.10 YELLOWSTONE RAWS, OR.......3.91 BONNEVILLE DAM, OR.........3.73 WILKINSON RAWS, OR.........3.54 LITTLE MEADOWS, OR.........3.50 ASTORIA, OR................3.42 ELKHORN MTN, WA............3.39 TROUT CREEK RAWS, OR.......3.35 MCMINNVILLE, OR............3.33 SCOTTS MILLS, OR...........3.20 WANDERERS RAWS, OR.........3.19 VANCOUVER, WA..............3.14 GOODWIN PEAK RAWS, OR......3.14 PORTLAND AIRPORT...........3.12 PEPPER CREEK, WA...........3.10 RED BOX RAWS, OR...........3.08 DETROIT, OR................3.08 HILLSBORO, OR..............3.01 VILLAGE CEEKR RAWS, OR.....2.97 REDHILL, OR................2.80 JUMP OFF JOE, OR...........2.70 GRESHAM, OR................2.70 PEBBLE RAWS, OR............2.63 ABERNATHY, WA..............2.62 SANTIAM JUNCTION, OR.......2.60 GREEN POINT RESERVOIR, OR..2.60 BOULDER CREEK RAWS, OR.....2.53 MAPLETON, OR...............2.50 SPUD MOUNTAIN, WA..........2.48 MARION FORKS, OR...........2.40 CASCADIA, OR...............2.35 HOGG PASS, OR..............2.30 BLAZED ALDER, OR...........2.30 BRUSH CREEK, OR............2.28 NWS PORTLAND, OR...........2.22 HIGH POINT RAWS, OR........2.20 POLLY RAWS 3320, OR........2.12 FERN RIDGE WEAT, OR........2.06 DEE FLAT AG 115, OR........2.06 MIDDLE MTN RAWS, OR........2.05 TROUTDALE, OR..............2.02 THREE LYNX, OR.............2.00 S FORK BULL RUN, OR........2.00 AURORA AIRPORT, OR.........1.94 SALEM AIRPORT, OR..........1.93 DUNE RAWS, OR..............1.91 FALLS CITY, OR.............1.90 AURORA, OR.................1.83 SALT CREEK FALLS, OR.......1.80 PEAVINE RIDGE, WA..........1.80 FINLEY RAWS , OR...........1.78 EUGENE, OR.................1.72 SIGNAL PEAK, OR............1.69 HOOD RIVER, OR.............1.60 CLACKAMAS LAKE, OR.........1.60 MARMOT, OR.................1.52 EAGLE CR RAWS, OR..........1.49 COTTAGE GROVE, OR..........1.42 PARKDALE, OR...............1.41 MUD RIDGE, OR..............1.40 MCKENZIE, OR...............1.40 DALY LAKE, OR..............1.40 UPPER SODA, OR.............1.39 KELSO, WA..................1.30 FIELDS RAWS, OR............1.30 CASCADE SUMMIT, OR.........1.30 COUGAR DAM, OR.............1.25 PINE GROVE, OR.............1.22 CORVALLIS, OR..............1.22 SUMMIT , OR................1.20 ROARING RIVER, OR..........1.20 STAYTON, OR................1.19 COTTAGE GROVE, OR..........1.05 HOLLAND MEADOWS, OR........1.00 CANYON CR RAWS, OR.........1.00 MERWIN DAM, OR.............0.94 HILLS CREEK, OR............0.94 ESTACADA, OR...............0.90 DORENA, OR.................0.82 CLAY CR RAWS, OR...........0.76 FOSTER DAM, OR.............0.74 LOOKOUT POINT, OR..........0.72 LOWELL, OR.................0.71
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By Rod Hill on 2011-11-22
Starting Monday and lasting through Sunday, this up-coming holiday week will see very active weather. Here are the highlights, travelers should be aware of: (Live Cameras can be seen on the Ski Forecast & Northwest pages.)
1. Snow levels rise above Government Camp Monday afternoon. Snow levels above most Cascade passes Tuesday and Wednesday morning. Snow levels below Cascade passes, Wednesday afternoon - Friday. Rising snow levels Saturday and then falling below passes Sunday. Update found on the Ski Forecast page.
2. Starting Monday, all Coast Range passes will see rain, with no chance of snow through Sunday.
3. Strong south winds at the coast and possibly the Coast Range, Monday - early Wednesday. Update on the Coast page.
4. Tuesday will be the best chance for valley wind gust to 45 mph or higher.
5. Highest coast winds Monday overnight - early Tuesday could reach 100 mph gusts!
6. Wet days should be expected coast and valley. Here is the weather schedule: Warm front Monday, very warm air mass Tuesday, weak front Wednesday, stronger cold front Thursday evening, cold front Sunday.
7. Heavy rain Monday night - Tuesday night. Coast totals of 3.00" plus, mountain, 4-6" possible, metro areas 2-3.00". Rivers will rise, I will let you know if any flood concerns arise.
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I hope you get the idea - very active weather all week - lots to keep track of, if you are traveling!
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