Confidence continues to increase that significant impacts from a combination
of ice, sleet and/or snow are likely across the entire area on Tuesday. This
will not be the "typical" event for the local area for two reasons:
(1). The precipitation will occur over a broad time period throughout the day
on Tuesday, rather than just a brief period early in the morning and (2).
Accumulation amounts, particularly of sleet and/or snow, are likely to be
higher than we normally see with local winter weather events.
Periods of light rain will mix with and then change to a mixture of sleet, freezing rain and possibly light snow starting around 6am on Tuesday morning. Present indications suggest that this mix will then increase into the morning hours.
Temperatures are expected to fall to near/around freezing by 6-7am on Tuesday, and continue to slowly fall into the remainder of the daytime hours, reaching the middle 20s during the evening hours. As temperatures continue to fall during the day, the mixed precipitation that is expected during the morning hours will change mostly to light snow during the afternoon hours. Some periods of sleet may still mix with the snow at times during the afternoon.
...Ice Accumulation Forecast...
Ice accumulation of up to around 0.1 inch is expected with this event, most of which will likely occur from after 6am through about 12 Noon. Depending upon how much of the mixed precipitation on Tuesday morning falls as freezing rain vs. the other types, some spots could see greater than 0.1 inch but likely less than 0.2 inch of ice accumulation during that same time period.
Ice accumulation of around 0.1 inch would mainly form a light glaze on exposed surfaces, especially metallic surfaces, colder elevated surfaces such as bridges, overpasses, etc., (especially if they are untreated), and roadways that are lesser traveled and/or untreated. Tree limbs and exposed power lines may also start to see a glaze-over especially if the near 0.1 inch ice amounts are realized. In those spots that receive slightly more than 0.1 inch of glaze, tree limbs would glaze over on an increasing basis, and other surfaces would begin to be coated as well, including a greater expansion on power lines.
...Sleet and/or Snow Accumulation Forecast...
Sleet and/or a combined sleet/snow accumulation of up to around 1.0 inch is expected with this event. This would most likely occur from after 12 Noon through about 6pm on Tuesday, with decreasing amounts into the early-mid evening hours. If the glaze ice accumulation occurs as expected (see above), the sleet and/or snow would be able to accumulate on most any exposed surface that has a glaze of ice, including many roadways, and especially those that are untreated.
...Transportation Impacts - Widespread...
Transportation impacts are likely to reach "widespread" status across the local area with this event. Impacts will begin on Tuesday morning and increase throughout the day. Elevated surfaces such as bridges and overpasses would likely be impacted first, followed by the lesser traveled/untreated surface roadways and then other roadways depending upon the extent of the heavier precipitation, amount of traffic on the roads, and the type of treatment the roads are receiving (if any).
...Power Impacts - Scattered to Regional...
Power impacts are expected to reach "scattered to regional" status across the local area with this event. Areas with exposed power lines would be most vulnerable, and especially if any concentrated spots of greater than 0.1 inch ice accumulation are observed in those areas. North winds will gust 25-30 mph throughout much of the day on Tuesday, and this could aggravate the condition at times in at least parts of the area, especially where the higher end of the ice accumulation occurs.
...Impacts on Trees - Isolated to Scattered...
Impacts on trees are expected to reach "isolated to scattered' status across the local area with this event. Ice glazing of up to 0.1 inch does not typically cause significant issues with downing of tree limbs, so this would primarily be of concern in areas that may receive slightly more than 0.1 inch of glaze, and on any trees that were in poor condition to begin with. North winds will gust 25-30 mph throughout much of the day on Tuesday, and this could aggravate the condition at times in at least parts of the area, especially where the higher end of the ice accumulation occurs.
We will continue monitoring the situation and issue updates as conditions warrant.
Periods of light rain will mix with and then change to a mixture of sleet, freezing rain and possibly light snow starting around 6am on Tuesday morning. Present indications suggest that this mix will then increase into the morning hours.
Temperatures are expected to fall to near/around freezing by 6-7am on Tuesday, and continue to slowly fall into the remainder of the daytime hours, reaching the middle 20s during the evening hours. As temperatures continue to fall during the day, the mixed precipitation that is expected during the morning hours will change mostly to light snow during the afternoon hours. Some periods of sleet may still mix with the snow at times during the afternoon.
...Ice Accumulation Forecast...
Ice accumulation of up to around 0.1 inch is expected with this event, most of which will likely occur from after 6am through about 12 Noon. Depending upon how much of the mixed precipitation on Tuesday morning falls as freezing rain vs. the other types, some spots could see greater than 0.1 inch but likely less than 0.2 inch of ice accumulation during that same time period.
Ice accumulation of around 0.1 inch would mainly form a light glaze on exposed surfaces, especially metallic surfaces, colder elevated surfaces such as bridges, overpasses, etc., (especially if they are untreated), and roadways that are lesser traveled and/or untreated. Tree limbs and exposed power lines may also start to see a glaze-over especially if the near 0.1 inch ice amounts are realized. In those spots that receive slightly more than 0.1 inch of glaze, tree limbs would glaze over on an increasing basis, and other surfaces would begin to be coated as well, including a greater expansion on power lines.
...Sleet and/or Snow Accumulation Forecast...
Sleet and/or a combined sleet/snow accumulation of up to around 1.0 inch is expected with this event. This would most likely occur from after 12 Noon through about 6pm on Tuesday, with decreasing amounts into the early-mid evening hours. If the glaze ice accumulation occurs as expected (see above), the sleet and/or snow would be able to accumulate on most any exposed surface that has a glaze of ice, including many roadways, and especially those that are untreated.
...Transportation Impacts - Widespread...
Transportation impacts are likely to reach "widespread" status across the local area with this event. Impacts will begin on Tuesday morning and increase throughout the day. Elevated surfaces such as bridges and overpasses would likely be impacted first, followed by the lesser traveled/untreated surface roadways and then other roadways depending upon the extent of the heavier precipitation, amount of traffic on the roads, and the type of treatment the roads are receiving (if any).
...Power Impacts - Scattered to Regional...
Power impacts are expected to reach "scattered to regional" status across the local area with this event. Areas with exposed power lines would be most vulnerable, and especially if any concentrated spots of greater than 0.1 inch ice accumulation are observed in those areas. North winds will gust 25-30 mph throughout much of the day on Tuesday, and this could aggravate the condition at times in at least parts of the area, especially where the higher end of the ice accumulation occurs.
...Impacts on Trees - Isolated to Scattered...
Impacts on trees are expected to reach "isolated to scattered' status across the local area with this event. Ice glazing of up to 0.1 inch does not typically cause significant issues with downing of tree limbs, so this would primarily be of concern in areas that may receive slightly more than 0.1 inch of glaze, and on any trees that were in poor condition to begin with. North winds will gust 25-30 mph throughout much of the day on Tuesday, and this could aggravate the condition at times in at least parts of the area, especially where the higher end of the ice accumulation occurs.
We will continue monitoring the situation and issue updates as conditions warrant.
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