Heavy Rainfall to Bring Flooding Threat to California; Heavy Snow in the Sierra

A strong atmospheric river will bring heavy rainfall to California through the holiday week. The heaviest rainfall is expected on Wednesday in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall is expected in the Sierra Nevada from the atmospheric river, raising concerns for major snow‐load impacts. Travel may be difficult to impossible over the passes. Read More >

basics header

General Topics

Cold Season Topics

Convective and Heat Topics

research header

General Topics

Cold Season Topics

Severe Weather Topics

2014 Prescott/Groom Creek Tornado Case Study
2003 August Rotating Supercell Case Study
2002 September Severe Weather Cast Study
Observation of a Supercell Thunderstorm over High Terrain in Northern Arizona
Forecasting Severe Weather Along the Mogollon Rim Convergence Zone
Evolution of a Mesoscale Convective Vortex over Northern Arizona
Forest Damage Associated with Tornadoes in Northern Arizona
Synoptic Environments Associated with Tornadoes in Northern Arizona
Radar Observations of the Early Evolution of Bow Echoes © American Meteorological Society. Used with permission.
The Development of Severe Convection Along a Dry Line in Northern Arizona
Supercells in Environments with Atypical Hodographs © American Meteorological Society. Used with permission.
A Comparison of Wind Speed and Forest Damage Associated with Tornadoes in Northern Arizona © American Meteorological Society. Used with permission.
Interactions between a Supercell and a Quasi-Stationary Frontal Boundary © American Meteorological Society. Used with permission.

Local Research Citations

Blanchard, D. O., 2008: Interactions between a Supercell and a Quasi-Stationary Frontal Boundary. Mon. Wea. Rev., 136, 5199–5210, https://doi.org/10.1175/2008MWR2437.1.

Blanchard, D. O., 2011: Supercells in Environments with Atypical Hodographs. Wea. Forecasting, 26, 1075–1083, https://doi.org/10.1175/WAF-D-11-00012.1.

Blanchard, D. O., 2013: A Comparison of Wind Speed and Forest Damage Associated with Tornadoes in Northern Arizona. Wea. Forecasting, 28, 408–417, https://doi.org/10.1175/WAF-D-12-00046.1.

Klimowski, B. A., M. R. Hjelmfelt, and M. J. Bunkers, 2004: Radar Observations of the Early Evolution of Bow Echoes. Wea. Forecasting, 19, 727–734, https://doi.org/10.1175/1520-0434(2004)019<0727:ROOTEE>2.0.CO;2.