Extreme weather killed more than the 688 people included in NOAA’s Monday report on 2021’s billion dollar disasters, Buzzfeed reports. In addition to events intentionally excluded from the report, like August flooding that killed 20 people in Tennessee, NOAA dramatically undercounts the number of people killed by extreme cold in Texas in February and extreme heat in the Pacific Northwest in late June.

NOAA’s official count included just 226 deaths caused by the extreme cold that descended on Texas and broad swaths of the central U.S. in February. Not only is that number lower than Texas’ official revised count of 246, it is dwarfed by the more than 700 deaths Buzzfeed determined were caused by the freeze. NOAA also said 229 people died in the PNW heatwave, far below Buzzfeed’s analysis of state records compiled by the CDC that found approximately 670 people were killed in one week at the height of the heatwave, which was described as “virtually impossible” without human-caused climate change.

The discrepancies are primarily caused by gaps in cause-of-death reporting, with many deaths attributed to underlying conditions, particularly cardiovascular disease, that can be worsened by extreme heat and cold. NOAA amended its report after being contacted by Buzzfeed to acknowledge the two events may have caused “hundreds of additional deaths.” (Buzzfeed; Climate Signals background: June 2021 PNW heatwave, Feb. 2021 Polar Vortex breakdown, Flooding)