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Area forecast discussion
National Weather Service Grand Rapids Michigan
145 PM EDT Thu Jun 20 2019

Latest update...

issued at 328 am EDT Thu Jun 20 2019

- heavy rain through this morning

- potential for more rain over the weekend into early next week


Discussion...(today through next wednesday)
issued at 328 am EDT Thu Jun 20 2019

Bands of moderate to heavy rain have developed and spread across
the central and northern forecast area so the forecast has been
changed to account for this further northward expansion.
Instability is limited to the point that thunder is left out of
the forecast for today. Area of rain gradually diminishes this
morning and tapers off this afternoon as sfc low translates east
and drying begins as sfc and upper ridging builds in for Friday.

Model guidance is trending towards a slower approach of the warm
front for Friday night and Saturday so mesoscale convective system activity should remain
south of lower Michigan Friday night. There will be a better
chance for rain on Saturday night as mesoscale convective system activity could fire up
over Wisconsin and move into southwest lower Michigan.

Juicy airmass with pwats near 2 inches will mean any deeper
updrafts are capable of dropping heavy amounts of rain in a short
time. Shortwave trough axis moves through on Monday with enhanced
precip chances then some drying out possible Tuesday and Wednesday
in quasi-zonal flow.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 145 PM EDT Thu Jun 20 2019

Rain and IFR conditions that have plagued the area since last
night, is now improving and gradually moving out from west to
east. This trend will slowly continue through 00z this evening.
This will occur as clouds lift from IFR to MVFR, the clouds will
eventually scatter out. Clouds will be limited after 03z or so,
through the end of the period. Winds will slowly shift from NE, to
the NW, and even west for Friday.


issued at 328 am EDT Thu Jun 20 2019

Winds and waves should remain below 25 knots and 4 feet through
Friday. There will continue to be areas of fog at times. Some
heavier rain will continue this morning south of Grand Haven and
another round of heavy rain is possible Saturday night.


GRR watches/warnings/advisories...


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