Area forecast discussion National Weather Service Grand Rapids Michigan 640 PM EDT Sat may 25 2013 Latest update... aviation Synopsis... issued at 340 PM EDT Sat may 25 2013 High pressure will continue the stretch of quiet weather into Sunday. High clouds will stream into the area but we will remain dry both tonight and Sunday. A warm front will gradually nudge toward the southern Great Lakes Sunday night into Monday night. The advancing warm front will bring increasing chances for rain as we move from Memorial Day into Tuesday. Best chances for rain will come Monday night into Tuesday. && Short term...(this evening through Monday night) issued at 340 PM EDT Sat may 25 2013 Have opted to issue a frost advisory for portions of central lower Michigan...essentially the northeast six counties of the County Warning Area...from lake over to Clare and Newaygo over to Isabella counties. Dew points up that way remain very dry in the lower 30s. With the thicker cloud remaining southeast of that area...dry air in place and light winds...frost is likely along with temperatures dipping well into the 30s. Focus then shifts to a slowly advancing warm front that will lift our direction from the middle Mississippi Valley. Showers are already occurring well northeast of the warm front across portions of Illinois and see this activity pressing into lower Michigan with time. It will remain dry tonight and Sunday...but beginning Sunday night warm air advection will bring showers to the far southwest corner of the state. Precipitation will try to nose into the area Memorial Day and Monday night...but it will be fighting a dry air mass. Feel it will make its best push into the County Warning Area Monday night. Have chance probability of precipitation in the forecast Sunday night through Monday night lifting slowing north and northeast with time. Long term...(tuesday through saturday) issued at 340 PM EDT Sat may 25 2013 A warm front will bring scattered showers and thunderstorms Tuesday and Tuesday night. Temperatures will be quite warm Wednesday through Friday in a southerly flow warm air advection regime in the warm sector. Maximum temperatures Wednesday through Friday should easily reach the lower to middle 80s with low temperatures in the 60s. A few showers and storms are possible very late next week into the weekend as the continued southerly flow leads to increasing moisture and as a low pressure system advances east into the upper Midwest region Friday and Saturday. && Aviation...(for the 00z tafs through 00z monday) issued at 640 PM EDT Sat may 25 2013 VFR conditions will continue overnight through Sunday. Some high clouds will linger tonight and Sunday. Wind direction will veer to the east overnight and then stay out of the east with wind speeds tonight through Sunday afternoon below 10 kts. && Marine... issued at 340 PM EDT Sat may 25 2013 Low waves and light winds will continue through Sunday evening. An increasing southeast flow Sunday night into Memorial Day will begin to bring up wave heights...but the flow will be off shore so nearshore waves will remain low. Shower and storm chances will increase gradually from the south Sunday night into Monday night. && Fire weather... issued at 340 PM EDT Sat may 25 2013 Dry conditions will persist into Sunday under high pressure. A warm front will gradually lift northeast with time from the plains early next week bringing periods of showers and storms. A warmer and more moist air mass will press in for much of next week. Relative humidity values will dip toward 30 percent again Sunday afternoon...but winds will remain light. Highs on Sunday and Monday will rise into the upper 60s to around 70. && Hydrology... issued at 340 PM EDT Sat may 25 2013 Only 2 river advisories remain from the recent heavier rain across central lower Michigan...Scottville and Montana. Pleasant. Dry weather tonight and Sunday will allow rivers to continue to recede as crests move downstream. A more active pattern will be setting up for next week...with rounds of showers and storms possible. && GRR watches/warnings/advisories... Michigan...frost advisory from 2 am to 8 am EDT Sunday for miz038>040- 044>046. Lm...none. && $$ Synopsis...Duke short term...Duke long term...Laurens aviation...Laurens fire weather...Duke hydrology...Duke marine...Duke