80303 Weather -- Boulder, CO

80303 -- South and Central Boulder, CO

Zip code 80303 covers south-central and southeast Boulder, including the elevated Table Mesa neighborhood on the NCAR mesa, the mid-century residential areas of Martin Acres and Baseline, and the lower-elevation Frasier Meadows and Keewaydin Meadows neighborhoods near Baseline Reservoir. Elevations range from around 5,290 feet in the eastern sections to over 5,530 feet at Table Mesa -- a range that produces noticeable microclimate variation within the zip.

The 80303 zip is home to the National Center for Atmospheric Research (NCAR) Mesa Lab, CU Boulder's main campus along its northern edge, and the South Boulder Recreation Center. South Boulder Creek and Baseline Reservoir provide significant open-space and recreational resources for 80303 residents year-round.

Fire Risk and History

80303 has a moderate wildfire risk. The western edge of the zip -- particularly the Table Mesa neighborhood and the NCAR Mesa Lab area -- borders South Boulder Creek Open Space directly, placing portions of 80303 within the wildland-urban interface zone. The elevated mesa terrain and adjacent grasslands carry meaningful fire exposure during dry Chinook wind conditions. The lower-elevation eastern neighborhoods of Martin Acres, Baseline, and Keewaydin Meadows have lower fire risk due to surrounding urban development. During the 2021 Marshall Fire, 80303 was not under evacuation but experienced significant smoke. Residents in western portions of the zip should review the City of Boulder's Wildfire Mitigation Program.

Elevation and Microclimate

Elevation across 80303 varies from approximately 5,290 feet in the eastern sections to over 5,530 feet at Table Mesa, producing different weather conditions within the same zip code. The mesa position of Table Mesa creates exposure to southwest wind and orographic cloud development that the lower neighborhoods do not experience. Summer temperatures in the eastern neighborhoods run 2–4 degrees warmer than the mesa top. UV radiation across 80303 is roughly 20 percent stronger than at sea level.

Flood Zone Information

80303 is classified FEMA Flood Zone X with minimal flood risk for most of the zip. South Boulder Creek runs along the western edge of the zip, and portions near the creek corridor may have localized flood exposure. The September 2013 regional flood event produced significant flows in South Boulder Creek, with some trail closures and open-space impacts, but residential areas of 80303 were largely unaffected. Property owners near any drainage feature or the South Boulder Creek corridor should verify their specific parcel designation at FEMA's Flood Map Service Center.

Neighborhoods in 80303

• Table Mesa
• Martin Acres
• Baseline
• Frasier Meadows
• Arapahoe Ridge
• Keewaydin Meadows