Atmospheric River affecting Alaska
![](https://cimss.ssec.wisc.edu/satellite-blog/wp-content/uploads/sites/5/2022/01/mimictpw_alaska_24hEnding1700UTC_21January2022.gif)
MIMIC Total Precipitable Water fields for the 24 hours ending 1700 UTC on 21 January, above, show abundant moisture flowing into southern Alaska. Hourly GOES-17 infrared imagery (Band 13 clean window infrared imagery at 10.3 µm), below, shows a large cyclonic circulation to the south and west of Alaska that is helping to draw moisture towards the state. Level 2 Total Precipitable Water (TPW) is overlain on the imagery and two things stand out: because it is a clear-sky only product, and because the north Pacific Ocean is very cloudy on the 21st, there is little TPW information. Also, GOES-R Total Precipitable Water is not completely Full Disk; TPW is computed to a Local Zenith Angle of 67o (ATBD) and you can see the cut-off for the product in northwestern Canada. Those two things argue for the utility of microwave detection of moisture over Alaska, as shown above.
![](https://cimss.ssec.wisc.edu/satellite-blog/wp-content/uploads/sites/5/2022/01/GOESCleanWindowTPW-20220121_1200_to_1700stepanim.gif)
Much of Alaska Southeast from Yakutat to Wrangell is under a Flood Watch. (Image, taken from this site)