The University of Tulsa

Mountain Cedar Pollen Forecast

SATURDAY / SUNDAY

 

Date Issued: 10 January 2009

Mountain Cedar Location(s): Edwards Plateau, Texas

Regional Weather: : Saturday and Sunday, Jan 10 and 11. TX/OK: A strong cold front moved through the region late on Friday and early this morning bringing much colder temperatures to the Texas-Oklahoma region. Temperatures will recover some this afternoon although highs will still be 20 to 30 degrees colder than Friday. The cold front brings very dry air to the region with strong northerly winds during the day today. The very dry air mass and mostly clear skies and light night time winds will facilitate radiation cooling and large diurnal temperature ranges. Overnight lows will range from the low 20s to the low 30s tonight. Temperatures will moderate on Sunday with temperatures in the 50s in Oklahoma and 60s in Texas. Skies will be clear to partly cloudy with light to moderate variable winds. Low humidity will continue tomorrow and cold overnight times will be in place again on Sunday night.


Trajectory weather: The air mass trajectories from the Edwards Plateau today move to the south under the influence of strong northerly winds. Each of the trajectories show characteristics associated with the cold air as the air masses sink towards the ground and move primarily at ground level. Conditions at the source areas will be cold today but dry with sunny clear skies in most areas. The trees are near the peak of the pollen release season; therefore, some pollen may be released but the cold temperatures should reduce levels today. In addition, atmospheric conditions are not particularly good for pollen entrainment and transport downwind. Sunday's trajectories are variable across the Plateau under the influence of the variable winds. Conditions at the source areas will be again be cold tomorrow morning but warming to the 60s. The cold morning temperatures will limit pollen release to the afternoon hours. Although there is a significant chance of pollen release tomorrow, conditions for entrainment and travel will not be ideal.

OUTLOOK: *** Low to Moderate Threat today/ Moderate to High Threat on Sunday *** Mixed conditions for pollen release today. Sunny skies with dry windy conditions but cold temperatures coupled with moderate to strong winds across the region result in mixed conditions for pollen release today. Since the trees are near their peak release period significant amounts of pollen release might be expected in sheltered areas where localized temperatures may be greater. However, overall the cold conditions should restrain significant release. The trajectory characteristics show poor atmospheric conditions for entrainment and travel downwind. Across the region the cold air will move the atmosphere along the ground, which usually results in the filtration of entrained particles as they travel. As a result any pollen released today will remain close to the source areas. Conditions for pollen release improve tomorrow. Although overnight temperatures will be low, it will warm to the 60s throughout the source areas. Significant release may be expected. Trajectory characteristics are still not ideal for transport tomorrow, so pollen released will again stay close to the source areas.

Trajectory Start (s) (shown by * on map): Austin, TX; Junction, TX; San Angelo, TX.

SATURDAY

AUSTIN

JUNCTION

SAN ANGELO

EDWARDS PLATEAU COMPOSITE

SUNDAY

AUSTIN

JUNCTION

SAN ANGELO

Prepared by: Estelle Levetin (Faculty of Biological Science, The University of Tulsa, 800 S. Tucker Dr., Tulsa, OK 74104) and ) and Peter K Van de Water (Department of Earth and Environmental Science, California State University Fresno, 2576 East San Ramon Avenue, M/S ST24, Fresno CA 93740-8039). This forecast gives the anticipated future track of released Mountain Cedar pollen, weather conditions over the region and along the forecast pathway, and an estimated time of arrival for various metropolitan areas.

 

Questions: Aerobiology Lab e-mail: pollen@utulsa.edu

 

Return to Forecasting Home Page