CW3E Subseasonal Outlook: 1 March 2024

CW3E Subseasonal Outlook: 1 March 2024

March 1, 2024

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Summary provided by Z. Yang, C. Castellano, J. Wang, M. DeFlorio, and J. Kalansky; 1 March 2024

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*Outlook products are considered experimental

CW3E Event Summary: 18-20 February 2024

CW3E Event Summary: 18-20 February 2024

27 February 2024

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Low-Pressure System and Atmospheric River Produce Heavy Rain and Snow in CA

  • An atmospheric river (AR) associated with a slow-moving area of low pressure brought widespread precipitation to California during 18–20 Feb.

The AR:

  • A deepening mid-level trough off the US West Coast interacted with a remnant plume of subtropical moisture, leading to an AR landfall over California on 18 Feb.
  • AR1–2 conditions (based on the Ralph et al. 2019 AR Scale) were observed in coastal Northern and Central California.
  • As the eastward progression of the trough stalled and the synoptic-scale flow became more southerly, the AR briefly re-intensified over Southern California, prolonging precipitation over the Transverse Ranges.

Impacts:

  • The heaviest precipitation occurred in the western Transverse Ranges, with more than 10 inches in some locations.
  • At least 1–3 feet of snow fell in the Sierra Nevada, with higher amounts in the vicinity of Lassen Peak.
  • Heavy rain falling on moist soils caused minor riverine flooding in the Sacramento Valley.
  • Flooding and mudslides closed portions of US-101, SR-1, SR-33, and SR-150 in Ventura and Los Angeles Counties.
  • Portions of coastal Southern California have received more than 75% of their normal total annual precipitation during the first 3 weeks of February.
  • Unusually cool and wet conditions during the month of February have facilitated a dramatic improvement in snowpack conditions throughout the state.

Click images to see loops of West-WRF IVT/IWV analyses and forecasts

Valid: 0000 UTC 18 February – 0000 UTC 21 February 2024


 

 

 

 

 

 

 

 

 

 

 

Summary provided by C. Castellano, S. Bartlett, P. Iniguez, and S. Roj; 27 Feb 2024

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CW3E Publication Notice: Vientos – A new satellite mission concept for 3D wind measurements by combining passive water vapor sounders with Doppler wind lidar

CW3E Publication Notice

Vientos – A new satellite mission concept for 3D wind measurements by combining passive water vapor sounders with Doppler wind lidar

February 19, 2024

In the recent publication “Vientos – A new satellite mission concept for 3D wind measurements by combining passive water vapor sounders with Doppler wind lidar” in the Bulletin of the American Meteorological Society by CW3E collaborator and University of Arizona professor Xubin Zeng, among co-authors across institutions including CW3E’s Anna Wilson, propose a new satellite mission to address the challenge in accurately characterizing three-dimensional distribution of horizontal wind vectors (3D winds): Vientos. This proposed satellite mission will combine 2 or more passive water vapor sounders with Doppler wind lidar to accurately measure these 3D winds. This work contributes to CW3E’s 2019-2024 Strategic Plan, in particular the Priority Area dedicated to Atmospheric River Research and Applications by suggesting a transformative modernization of atmospheric measurements.

3D winds are integral to the Earth system, and yet, we do not currently have a method of accurately observing 3D winds with requisite space/time coverage. Information on 3D wind structures in and around atmospheric rivers in particular has the potential to be transformational for our understanding of the underlying processes. Further, our reliance on reanalysis data has been proved by recent studies to contain some systematic dynamical biases and errors. Thus, the need for Vientos is clear. The feasibility of the Vientos concept, which would retrieve 3D atmospheric motion vectors through tracking the movement of water vapor, followed by a bias correction using lidar measurements, has been proved doable by recent missions that explore combining active and passive observations as part of the global observing system.

The Vientos mission would be able to address many scientific questions and contribute to a variety of applications. In addition to 3D wind observations, it would also provide 3D water vapor and temperature data while wind lidar provides aerosol measurements of the near storm environment (Figure 1, from the paper). This could provide many benefits to areas including but not limited to: numerical weather predictions, flight route planning in aviation, Forecast Informed Reservoir Operations (FIRO), wind energy, tracking transport of pollutants and aerosols, climate model evaluations, and carbon monitoring for international negotiations and policy making. Lastly, the essay explores different possible architectures of the project, each providing different resolutions and coverage based on budgets available coinciding with currently planned satellite missions.

Vientos emphasizes the synergy between passive sounders and wind lidar in a way that could fill a critical gap in Earth system scientific knowledge. To read more about the Vientos concept, access the entire publication here.

Zeng, X., Su, H., Hristova-Veleva, S., Posselt, D. J., Atlas, R., Brown, S. T., Dixon, R. D., Fetzer, E., Galarneau, T. J., Jr., Hardesty, M., Jiang, J. H., Kangaslahti, P. P., Ouyed, A., Pagano, T. S., Reitebuch, O., Roca, R., Stoffelen, A., Tucker, S., Wilson, A., Wu, L., & Yanovsky, I. (2024). Vientos – A new satellite mission concept for 3D wind measurements by combining passive water vapor sounders with Doppler wind lidar. Bulletin of the American Meteorological Society (published online ahead of print 2024). https://doi.org/10.1175/BAMS-D-22-0283.1

CW3E Subseasonal Outlook: 16 February 2024

CW3E Subseasonal Outlook: 16 February 2024

February 16, 2024

Click here for a pdf of this information.


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Summary provided by J. Wang, C. Castellano, Z. Yang, M. DeFlorio, and J. Kalansky; 16 February 2024

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*Outlook products are considered experimental

CW3E Event Summary: 26 January – 2 February 2024

CW3E Event Summary: 26 January – 2 February 2024

13 February 2024

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Atmospheric Rivers Produce Heavy Precipitation from Alaska to Southern CA

  • A family of atmospheric rivers (ARs) brought heavy precipitation to portions of Alaska, British Columbia, the Pacific Northwest, and California during 26 Jan – 2 Feb.

The ARs:

  • AR #1 made landfall in Oregon on 26 Jan and produced at least 2–6 inches of precipitation in portions of western Washington and Oregon.
  • AR #2 made landfall in British Columbia and southeastern Alaska on 28 Jan and produced 6–12 inches of precipitation over Vancouver Island, the Coast Mountains, the Alaska Panhandle, and the St. Elias Mountains.
  • AR #3 produced AR4 conditions (based on the Ralph et al. 2019 AR Scale) along the southern Oregon coast and AR3 conditions in coastal Northern California.
  • AR #3 brought widespread precipitation to California, including 4–8 inches of rain in the Northern California Coast Ranges and western Transverse Ranges, and 1–3 feet of snow in the Sierra Nevada.
  • All three ARs were fed from a tropical moisture source referred to as a Tropical Moisture Export (TME).

Impacts:

  • Rain falling on moist soils caused minor-to-moderate riverine flooding in western Washington during the first AR.
  • The greatest hydrologic impacts occurred in British Columbia during the second AR, with significant flooding near Pemberton, BC.
  • Minor flooding and several landslides were reported in Northern California during the third AR
  • This family of ARs and nearby essential atmospheric features were sampled by the NOAA and the 53rd Weather Reconnaissance Squadron as part of the AR Recon field campaign.

Click images to see loops of West-WRF IVT/IWV analyses and forecasts

Valid: 0000 UTC 26 January – 0900 UTC 2 February 2024


 

 

 

 

 

 

 

 

 

 

 

 

 

Summary provided by C. Castellano, S. Bartlett, J. Cordeira, P. Iniguez, J. Kalansky, M. Steen, and S. Roj; 13 Feb 2024

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