Lexington, Massachusetts, USA
Issued by the National Weather Service - Juneau, AK
Areas Affected: Glacier Bay; Eastern Chichagof Island; Cape Fairweather to Lisianski Strait; Admiralty Island; City and Borough of Juneau
Urgency: Future
Severity: Severe
Certainty: Possible
Alert Sent: Friday 9:30pm AKST
Alert Effective: Friday 9:30pm AKST
Alert Expires: Saturday 9:30am AKST (expect updated alert by this time)
Event Onset: Friday 9:30pm AKST
Event Ends: Saturday 9:00pm AKST
Issued by: NWS Juneau AK
...FLOOD WATCH REMAINS IN EFFECT THROUGH SATURDAY EVENING... An atmospheric river with multiple surges of moisture has moved into the panhandle and is possible to last into Sunday evening. Precipitation has mostly transitioned to rain past the Icy Strait corridor, and is still expected to transition for the northern inner channels overnight Friday. Snow levels are roughly 1500 to 2500 feet above sea level along the Icy Strait corridor through the southern panhandle. A brief, distinct lull in heavy rainfall is expected overnight Friday night into Saturday morning for the southern half of the panhandle, before another surge of moderate to heavy rain. Additional rainfall amounts from Friday night through Saturday night look to range around 1.5 to 3.0 inches in the southern panhandle, including Ketchikan and Metlakatla, 1.0 to 2.0 inches for the central inner channels including Petersburg, Wrangell, and Kake, 0.75 to 1.5 inches for the Icy Strait corridor, 1.0 to 2.0 for the Juneau area, and 1.0 to 1.5 inches for the far northern inner channels near sea level. Currently, expecting the snowpack to absorb most rainfall from this weekend system and produce minimal runoff in the northern half of the panhandle with a deep sea level snowpack. Therefore, snow, ice, or other debris could potentially block storm drains and allow for ponding of rain and snowmelt in areas that they normally would not collect, such as roadways or walkways. Another surge of moisture is looking increasingly likely for the southern half of the panhandle overnight Saturday and continuing through Sunday, and therefore, the flood watch was extended. There is growing confidence that very strong rain rates during the morning hours for the Ketchikan, Metlakatla, and Prince of Wales Island, with around a 40-60% chance for 3 hour rates exceeding 0.4 inches. This surge in precipitation may coincide with another surge of wind gusts, with sea level gusts possibly reaching as high as 50 mph Sunday evening. The southern panhandle could see 1.5 to 3.0 additional inches, the central inner channels could receive 1.0 to 2.0 additional inches, the Icy Strait corridor could receive 0.75 to 1.5 additional inches, and the Juneau area could receive 1.5 to 2.5 additional inches. Stay tuned for more information. * WHAT...Flooding caused by rain and snowmelt continues to be possible. * WHERE...The following areas, Eastern Gulf Coast and Central Inner Channels. This includes the cities of Gustavus, Hoonah, Tenakee Springs, Elfin Cove, Pelican, Angoon, And Juneau. * WHEN...Through Saturday evening. * IMPACTS...Storm drains and ditches are clogged with snow that may cause ponding of water in these poor drainage areas. * ADDITIONAL DETAILS... - Around 0.75" to 1.50" of rain occurred today along the Icy Strait corridor and Juneau area. Numerous reports of ongoing flooding over roadways and parking lots due rain and runoff across the Juneau and Hoonah areas today. Heavy rain will continue to fall on the existing snowpack which lead to increased runoff and ponding of water in poor drainage areas during the watch time frame. Through Saturday evening, an additional 0.75 to 1.25 inches for the Icy Strait corridor, with localized higher amounts possible, especially for Juneau. Depending on how culverts and storm drains behave during this upcoming rain, along with the additional rainfall of around 0.75 to 2.5 inches, with higher amounts near Juneau, the flood watch may be extended into Sunday.
You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop. Flooding may occur in poor drainage areas. Storm drains should be kept clear of debris as much as possible. Stay tuned to further developments by listening to your local radio, television, or NOAA Weather Radio for further information.
ID: urn:oid:2.49.0.1.840.0.0cfca5e1db9539602a61e862e67b3e4fee0d23a7.001.1 Codes: AKZ320, AKZ321, AKZ322, AKZ324, AKZ325 Link: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.0cfca5e1db9539602a61e862e67b3e4fee0d23a7.001.1