Rod's Weather Headlines

   Below is a statement from the National Weather Service.  Weekend rains in Portland, will likely break records.  

   Expected rainfall of more than 2.00" will break the all-time PDX September rain record which is 4.30" back in 1986. 

.SYNOPSIS...AUTUMN IS WASTING NO TIME GETTING STARTED IN THE PACIFIC 
  NORTHWEST. A VERY VERY WET PATTERN IS BEGINNING...WITH THE FIRST 
  SYSTEM IN A SERIES SPREADING IN TODAY WITH DECENT RAINS. THE NEXT 
  STRONGER AND WETTER FRONT IS FORECAST TO RAMP UP THE RAIN AND COASTAL 
  WIND ON SATURDAY CONTINUING INTO SATURDAY NIGHT. THE NEXT EVEN 
  POSSIBLY STRONGER SYSTEM IS FORECAST TO BRING MORE HEAVY RAIN AND 
  WIND TO THE FORECAST AREA LATER SUNDAY AND SUNDAY NIGHT. LOOK FOR 
  RECORD RAINS THIS WEEKEND INTO MONDAY. COOL AND SHOWERY WEATHER 
  SHOULD THEN LINGER WELL INTO NEXT WEEK. 
  &&  
   
  .SHORT TERM...TODAY THROUGH MONDAY...THE MODELS ARE GETTING MORE 
  CONSISTENT WITH THE DETAILS OF OUR HEAVY RAIN EPISODE THROUGH THIS 
  WEEKEND INTO EARLY NEXT WEEK. THESE STORMS WILL HAVE TROPICAL 
  MOISTURE WITH THEM...SOME FROM FORMER WESTERN TYPHOON PABUK. THESE 
  SERIES OF STORMS WILL PRODUCE RECORD RAINFALLS IN OUR AREA...AS WELL 
  AS STRONG WINDS AT THE COAST AND LOCALLY INLAND...AND HIGH SEAS NEAR 
  THE COAST. 
   
  THE FIRST SYSTEM WAS ALREADY SPREADING ONSHORE THIS MORNING. THE 
  RAIN WILL REACH THE PORTLAND AREA LATER THIS MORNING...AND SPREAD 
  SOUTH THROUGH THE DAY. THIS SYSTEM HAS 1.5 PWS FEEDING IT...AND 
  SHOULD PRODUCE MODERATE RAINS MUCH OF THE AREA INTO THE EVENING. 
   
  THE NEXT STRONGER FRONTAL SYSTEM AS MOISTURE FROM PABUK IN IT. THE 
  RAINS WILL INCREASE ON SATURDAY IN THE WARM ADVECTION AHEAD OF THE 
  SYSTEM ALONG THE FRONTAL BOUNDARY LEFT OVER FROM THE SYSTEM TODAY. 
  HEAVY RAIN WILL INCREASE THROUGH THE DAY ON SATURDAY ACROSS MOST OF 
  THE FORECAST AREA. THE GFS AND ECMWF MODELS BOTH SHOW THE ASSOCIATED 
  COLD FRONT APPROACHING THE COAST IN THE AFTERNOON...AND MOVING 
  ONSHORE SATURDAY NIGHT. THIS WILL BRING MORE HEAVY RAIN...WITH STRONG 
  WINDS AT THE COAST AND LOCALLY INLAND. THE RAIN WILL LIKELY BRING 
  AREAS OF URBAN AND SMALL STREAM FLOODING. THE WINDS COULD CAUSE TREE 
  DAMAGE AND POWER DISRUPTIONS ESPECIALLY AT THE COAST AND OVER THE 
  COAST RANGE BUT POSSIBLY IN THE VALLEYS AS WELL. 
   
  IF THE MODELS ARE TO BE BELIEVED...THERE MIGHT BE A BRIEF REPRIEVE OR 
  DECREASE IN THE RAIN LATE SATURDAY NIGHT AND EARLY SUNDAY...BUT NOW 
  THE MODELS ARE FOCUSING ON ANOTHER STRONG LOW APPROACHING THE COAST 
  SUNDAY AFTERNOON AND SWINGING THROUGH SUNDAY NIGHT AND EARLY MONDAY. 
  THIS WILL BRING MORE VERY HEAVY RAIN TO OUR AREA...AS WELL AS 
  POSSIBLY STRONG WINDS AT THE COAST AS WELL AS INLAND. THE WINDS WITH 
  THIS SYSTEM MAY BE STRONGER THAN THE SATURDAY STORM...WITH GUSTS NEAR 
  THE COAST UP NEAR 80 MPH POSSIBLE IF THE CURRENT MODELS ARE CORRECT. 
   
  PRECIPITATION AMOUNTS THROUGH MONDAY STILL LOOK TO BE 7 TO 10 INCHES 
  IN THE CASCADES AND THE COAST RANGE...WITH 2.5 TO 3.5 INCHES OR MORE 
  IN THE VALLEYS. THIS IS A VERY SIGNIFICANT RAIN EVENT FOR OUR AREA... 
  VERY UNUSUAL FOR LATE SEPTEMBER AND MORE LIKE A LATE OCTOBER OR 
  NOVEMBER OR LATER EVENT. TOLLESON 
   
  .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS... 
  THE EXTENDED MODELS CURRENTLY INDICATE THE HEAVIER RAIN WILL BE 
  WINDING DOWN SUN NIGHT. HOWEVER...EXPECT PERIODIC SHOWERS...SOMETIMES 
  HEAVY...TO CONTINUE THROUGH THE MIDDLE OF NEXT WEEK AS THE GULF OF 
  ALASKA LOW PUSHES TOWARD THE PAC NW. THE TIMING OF THE INDIVIDUAL 
  SHORTWAVES THAT WILL DRIVE THE MORE ORGANIZED SHOWERS IS SOMEWHAT 
  UNCERTAIN...BUT THE CONFIDENCE IN THE SHOWERY PATTERN IS HIGH. THERE 
  IS SOME INDICATION THAT A SHORTWAVE RIDGE WILL PROVIDE A BRIEF BREAK 
  FROM THE RAIN SOMETIME DURING THE SECOND HALF OF THE WEEK...BUT THE 
  DETAILS AND TIMING OF THIS FEATURE ARE VERY MUCH UP IN THE AIR AT 
  THIS POINT. TEMPERATURES ARE EXPECTED TO RUN A GOOD 5 TO 10 DEG BELOW 
  NORMAL THROUGH MUCH OF NEXT WEEK. PYLE 
  && 
   
  .AVIATION...INLAND...VFR EARLY WITH LOCAL IFR CONFINED TO KHIO. RAIN 
  BEGINNING EXPECTED TO BEGIN AROUND 16Z TO 17Z IN THE NORTH 
  INTERIOR...18Z TO 19Z SOUTH. CHANCES FOR MVFR CIGS INCREASE LATER IN 
  THE AFTERNOON...AND BECOME LIKELY THIS EVENING FOR MOST LOCATIONS.  
  AT THE COAST...MVFR OR LOWER CONDITIONS ON THE NORTH COAST WILL 
  SPREAD DOWN THE COAST LATER THIS MORNING AS A FRONT SPREADS RAIN INTO 
  THE AREA. 
   
  KPDX AND APPROACHES...VFR CONDITIONS THROUGH MID AFTERNOON IN LIGHT 
  RAIN. MVFR CIGS EXPECTED IN THE AFTERNOON/EVENING AS A FRONT STALLS 
  AND RAIN CONTINUES AT TIMES. 
  && 
   
  .MARINE...WINDS HAVE INCREASED TO SMALL CRAFT CONDITIONS (20 TO 25 
  KT) THIS MORNING IN ADVANCE OF A SET OF PROGRESSIVELY STRONGER 
  PACIFIC FRONTS. EXPECT THERE WILL BE A PERIOD OF LATER THIS AFTERNOON 
  AND EVENING BELOW 20 KT IN MANY SPOTS...BUT WILL KEEP THE SMALL CRAFT 
  ADVISORY GOING DUE TO SOME UNCERTAINTY ON WHEN WINDS RAMP BACK UP.  
   
  WINDS INCREASE TO GALES (35 KT TO 45 KT) SAT...LASTING INTO THE 
  EVENING. LATEST MODELS ARE A LITTLE FASTER FOR SAT SYSTEM SO HAVE 
  BUMPED UP TIMING A LITTLE...AND MAY NEED TO BUMP IT UP AGAIN...BUT 
  WILL MAKE THIS DECISION THIS AFTERNOON WHEN AN UPGRADE TO WARNING IS 
  LIKELY. SOME LOCAL GUSTS TO NEAR 50 KT CLOSE TO SHORE POSSIBLE SAT 
  AFTERNOON OR EARLY EVENING AS THE FRONT MOVES ASHORE...ESPECIALLY AS 
  THE FRONT NEARS...AS THERE MAY BE A CONVECTIVE ELEMENT TO THE FRONT 
  THAT CAN CREATE LOCALIZED STRONGER GUSTS. A NEW DEVELOPMENT IN 00Z 
  FRI GFS/ECMWF MODELS IS ANOTHER STRONG SYSTEM FOR SUN AFTERNOON. 
  EARLIER MODEL RUNS WERE DEPICTING IT MUCH WEAKER. THIS SYSTEM MAY BE 
  AS STRONG OR STRONGER THAN SAT SYSTEM. HAVE CONTINUED THE TREND 
  MODELS HAVE SHOWN TOWARD THE STRONGER SOLUTION. THIS COULD BE A STORM 
  BUT LOOKS TO AT LEAST BE A GALE. EXPECT TO HAVE SOMETHING OUT FOR 
  THIS SYSTEM BY MID AFTERNOON AT THE LATEST. 
   
  SEAS REMAIN BELOW 10 FT THROUGH FRI NIGHT...THEN BUILD INTO THE MID 
  TEENS SAT. LONGER PERIOD WESTERLY SWELL ARRIVES SAT NIGHT AND WILL 
  LIKELY EXCEED 20 FT BY SUN AFTERNOON. WITH PERIODS IN THE MID TEENS 
  BEACHES USUALLY EXPERIENCE HIGH SURF CONDITIONS WITH SEAS OF THIS 
  MAGNITUDE. /KMD 

Right on cue, mother nature delivers a wild punch, within hours of the Autumnal Equinox at 1:44, Sunday afternoon. 

Here are a few storm headlines:

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Heaviest rainfall:

Astoria 1.22 inches

Seaside 1.22

Kelso .59

Portland metro:  .10 - .30 inches on average

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Peak Wind Gusts:

Garibaldi  64 mph

Newport   56 mph

I-205 at Division  42 mph

PDX  37 mph

Salem  39 mph

Mt. Hood 7,000 feet 63 mph

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The snow level will lower to near 6,000 feet tonight and Monday.  Timberline Lodge may wake up to snow on the parking lot Monday morning!

The Autumnal Equinox will kick-off the fall season this Sunday at 1:44 p.m. pdt.  A true "fall" cold front will arrive hours later, bringing possible high winds to the coast, steady rain to the valley and snow levels Sunday night lowering to Timberline Lodge!

Sunday's rainfall will put Portland over the top for September rainfall.  The monthly average is 1.47 inches.  To date, PDX has 1.45 inches in the rain bucket.  Outlooks from the National Weather Service call for above normal rainfall to continue through October.  The temperature outlook shows no confidence.  However, the 90 day outlook shows above normal temperatures for November and December. 

According to climate records, here is a guideline of what to expect in the coming weeks:

1.  First week of October, the normal high temperature drops into the 60s.  The normal low drops into       the mid 40s on Oct. 13th.

2.  The daily probability of rain goes from 30 percent to 40 percent October 9th.  Meaning, historically, 4 out of 10 days over the past 30 years have seen measurable moisture.  The rain chance increases to 50 percent of October 20th.  On average, November is now considered Portland's wettest month.

3.  October is the month that Portland begins to see more clouds than sunshine.  Depending on weather patterns, the north valley will not see more sunshine than clouds until next April, May or June. 

Tuesday's high of 91 degrees at PDX becomes the ninth day of 90 degree heat this summer.  Other Tuesday highs include:

Salem 92

Vancouver  91

Troutdale 95

Hillsboro 91

McMinnville 94

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Forecasting the return of cooler Pacific air is always tricky, but forecast models suggest 90 degree temperatures will be possible through Saturday.  Several record highs will be in jeopardy.  The PDX record high for Sept. 11th is 94 degrees and the record for this Thursday is 92 degrees.  Perhaps most impressive about our mini heatwave is that 3 or more 90 degree days in a row would become the longest hot streak of our summer season! 

The average number of September 90 degree days is two, but the most on record is 8 days, back in the summer of 1974.  The average number of 90 degree days for the year is 13.  You may recall the summer of 2009, when PDX set the all-time record with 24, 90 degree days.

Stay cool, drink plenty of water and take comfort in the fact that  the sunset starting Wednesday the 11th will be before 7:30, meaning longer nights will bring hours of time to cool off. 

The National Weather Service estimates 50,000 lightning strikes hit the Northwest during the storm event.  The amount of rain & lightning is unusual for September.  An upper low moving inland produced an unstable atmosphere and unleashed the rain and electric storm. 

These rain reports are from the National Weather Service through 5:00 a.m. Friday morning.  Additional amounts of .25" or more is possible in the east metro through noon today. 

Salem:  2.23"

Portland 1.03"

Kelso 1.80"

Scappoose 1.19"

Vancouver 1.10"

Hillsboro 1.16"

Beaverton 1.39"

Gresham 1.20"

Oregon City 1.49"

Tualatin 1.87"

Canby 1.65"

Aurora 1.65"

McMinnville .57"

Newberg 1.75"

Corvallis 1.84"

Aumsville 3.59"

Albany 4.34"

Sandy 1.37"

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Astoria .31"

Newport .65"

Hood River .16"

Daily totals can always be found on the Northwest Forecast Page. Click on the blue climate link on the desktop site and select your option. 

Although the Autumnal Equinox will not turn the calender to fall until September 22nd, what is considered meteorological summer ended August 31st.  The summer forecast for June, July and August turned out to be correct!  Last spring, I told you to expect a nice summer with drier than normal weather and no long stretches of extreme heat.  In fact, my prediction of less than normal 90 degree days is also true so far!

Here is the summer report card for June - August:

Average high temperature:  80 degrees - one degree above normal

Average low temperature:  58 degrees - one degree above normal

Rainfall:  2.13 inches - below normal by .89 inches

Thunderstorms in the metro area:  3 days (not counting last night)

Number of 90 degree days:  8 (normal through October is 13 days)

Hottest temperature:  97 degrees, June 30th

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High humidity as been the story of our summer weather.  The average relative humidity for August was 63 percent, compared to 58 percent back in August of 2012.  The humid air has been brought by several long stretches of a southwest flow pattern aloft with a weak low pressure trough over the area, centered offshore.

Back in June, I wrote an article stating that Portland would likely see fewer than normal 90 degree days this summer.  The forecast was based on historical data showing less than the average of 13, 90 degree days, when PDX did not reach 90 until after June 10th.  This year's first 90 degree day was June 28th.  To date, the warmest temperatures this summer has been 97 degrees on June 30th.  The airport has recorded seven, 90 degree days so far this summer. 

Current forecast models show no chance of 90 degree heat through August 31st.  At this time, there are no signs of a hot September.  The latest date to see 90 degrees in Portland, was October 5th back in 1980.  While it is true that record highs during September are mostly 90 or higher, the record number of 90 degree days for any one September is 8 back in 1974.  The average number of 90 degree September days is two. 

Based on current data, it is unlikely that PDX will see more than 4 additional 90 degree days, which would give the summer of 2013 a total of 11 days, which would be two days below normal.  I hope you are enjoying our pleasant summer weather!

Clear skies Sunday night and Monday will bring three chances to view the International Space Station as it passes overhead.  The space station should be easy to spot.  You will be looking for what looks to be a commercial jet like feature, only higher in the sky.  If you go outside at the times listed below, you should see the flight!

Sunday evening:  10:48 p.m.  The station will move west/southwest to the southeast at 90 degrees in the sky.

Monday morning:  3:40 a.m.  Moving west/northwest to the southeastern sky at 87 degrees.

Monday evening:  10:00 p.m.  Appearing in the southwestern sky, moving to the east at 57 degrees.

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The station will be in orbit at 240 miles above Earth, flying at a speed of 17,500 mph!  The space station is as big as a football field and has a brightness equal to the planet Venus.  Each flight viewing will be visible for roughly 7 minutes.

The month of July ends at PDX with simply a trace of rain.  The lack of moisture becomes one of many years to see just a trace of July rainfall.  The year 1967 holds the dry July record with 0.00 inches.  Here is a list of other July reporting sites:

Downtown Portland (KGW):   0.00 inches ties for the driest

Vancouver:  0.00 inches ties for the driest

Hillsboro:  Trace ties for 2nd driest

McMinnville:  Trace ties for 2nd driest

Salem:  0.00 inches ties for driest

Eugene:  0.00 inches ties for driest

Astoria:  0.03 inches ties for 2nd driest

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You may recall that August 2012 saw only a trace of rain at PDX.  We are clearly in the middle of our dry season.  Current forecast outlooks call for above normal temperatures during the month of August.  July averaged less than a degree above normal for the month.  Outlooks also call for below normal rainfall to continue.  In fact our drier than normal weather pattern may continue through September. 

To date, PDX has had 6 days reach 90 degrees or warmer,  which is normal to date.  The season average is 13 days with 90 degree heat through September.  

90 degree temperatures are in the forecast for the first time this year.  Weather charts show hot weather this coming Sunday, Monday & Tuesday.  As July approaches, it should come as no surprise that hot weather is in the 7day forecast.  Portland averages 13 days each year of 90 degree temperatures and hotter.  Here is a list of the first 90 degree days over the past 10 years:

Year      1st 90 degree day      Number of 90 degree days all year

2003           June   4                                22 days

2004           June 17                               12 days

2005            May 27                                15 days

2006            May 15                                21 days

2007            May 30                                  9 days

2008            May 16                                15 days

2009            June  3                                 24 days  (all time record)

2010            July   7                                 11 days

2011            Aug.  20                                 7 days

2012            Aug.   4                                 11 days

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CONCLUSION - WHAT TO EXPECT THIS SUMMER:

Notice that all years above the average number of 13, 90 degree days had their first hot day before June 10th.  If this summer follows the pattern of the last 10 years, PDX will likely see 12 or less 90 degree or hotter days this summer.