[willamette-fcst] Silverton Hills AM Forecast_doug.doc
Willamette Valley Field Burning Forecast
willamette-fcst at listsmart.osl.state.or.us
Tue Jul 16 08:45:05 PDT 2013
SILVERTON HILLS FIELD BURNING FORECAST
OREGON DEPARTMENT OF FORESTRY WEATHER OFFICE
9:00 AM PDT TUES. JUL 16, 2013
BURN ADVISORY:
Agricultural burning is not recommended today.
Prep burning is not recommended today.
WEATHER DISCUSSION:
Abundant mid-level moisture is moving in from the south today over the area, and may bring some scattered light showers through the day to the valley. No significant rain is expected, and above average low-level temperatures will continue. Partly to mostly cloudy conditions will predominate through the day. Any marine surge later in the day into this evening is likely to be weak. Transport winds are likely to be weak but generally from the north later today.
The upper trough off the coast remains in place for the next several days, but with more southwesterly flow skies will return to mostly sunny on Wednesday.
TODAY'S FORECAST:
Partly cloudy with a few light showers.
Salem's high temperature today will be in the upper 80s.
Relative humidity: Will drop below 60% by 10:00 a.m. and to 35-40% by 5 p.m.
Surface winds: NE 5-10 mph this morning through the afternoon; NW 5-10 mph this evening.
Transport winds: Variable but generally N 5-10 mph
Mixing height: Rising to near 3500 feet this afternoon.
Salem's sunset tonight: 8:58 p.m.
(Salem Airport data for Monday, July 15th: High 89°F; Rainfall .00")
(Maximum Ventilation index expected today: 30)
EXTENDED DISCUSSION:
Upper ridging will persist through the weak and even strengthen late in the week, with the trough off the coast moving westward slowly. Expect mostly sunny conditions and continued very warm temperatures with maximums in the middle 80s.
The National Weather Service's digital forecast is available at:
http://forecast.weather.gov/MapClick.php?lat=44.90549606158295&lon=-122.8106689453125&site=pqr&unit=0&lg=en&FcstType=text
Notes:
1. Mixing height, as used here, is the lowest height at which the
potential temperature exceeds the potential temperature at the
surface. As a practical matter it is the approximate height to
which a smoke plume will rise assuming good ignition, dry fuels, and
winds less than about 15mph.
2. Transport winds are a layer average through the mixing height,
weighted slightly toward the winds at the top of the layer.
3. Ventilation Index is the height of the mixing layer (ft) times
the transport wind speed (mph) divided by 1000.
4. Surface wind direction is the general expected wind direction.
At a specific point surface winds are highly dependent on local
terrain conditions.
This forecast is provided under an agreement between the Oregon Department of
Agriculture and the Oregon Department of Forestry. For information contact ODA at 503-986-4701.
Doug Wesley
ODF Meteorologist
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://omls.oregon.gov/pipermail/willamette-fcst/attachments/20130716/b085695e/attachment.html>
More information about the willamette-fcst
mailing list