Last Updated on Sunday, 20 April 2014 06:58
Winds Statewide in a glance ...just go HERE(this link is also the 4th drop down under weather)
Apr 20, 2014 3:30 AM HST
Trade winds will increase today and tonight, then remain strong on Monday, before dropping back to moderate levels by midweek. Showers will continue to focus across windward and mauka areas, with showers spilling over into some leeward areas as well.
Radar loops indicate increased shower activity moving quickly westward across the state during the past few hours, but rain gauges show generally light accumulations over windward areas. The 12Z soundings show the inversion based between 5500 and 8000 feet, with winds around 850 mb (just below the inversion) increasing to 23-27 knots at Lihue. Satellite imagery continues to show abundant mid/high level cloudiness streaming northward across the region, to the east of a mid/upper level trough centered several hundred miles to the southwest. At the surface, a 1031 mb high is centered about 950 miles north of Kauai and is building eastward.
The primary weather concern through the short term is the potential for gusty advisory level trade winds, as strong high pressure passes by to the north of the state. The 00Z uh-wrf run continues to suggest that the strongest winds are likely to occur tonight and Monday, with 925 mb winds increasing to 35 to 40 knots in some areas. Model soundings do not show quite as strong an inversion as one would ideally like to see in order to maximize wind production at the surface, but still think that some of the typically favored downslope areas will receive at least minimal advisory conditions at times especially tonight and Monday. Earlier pushed back the start time of the wind advisory to 10 am this morning, and will not make any further changes at this point. See the latest advisory product for details on areas most likely to be affected by this event.
Otherwise, mimic-tpw satellite imagery and model data continue to suggest that an area of somewhat enhanced low level moisture will continue moving westward into the state this morning. Would expect this additional moisture within the building trade flow to support increased shower activity across windward and mauka areas, with some spillover into leeward sections.
Strong trades will prevail tonight and Monday as the high passes to our north, then trades should fall back to moderate levels on Tuesday with the high moving further away to the northeast. The other player in our weather during the early to mid week period will be a slow moving mid/upper trough to the southwest of the state. Guidance is a bit more emphatic with maintaining this feature in the mid levels (500 mb) than it was previously, but shows basically no reflection in the lower levels with a distinct dry layer maintained between the moisture aloft and the moist trade flow at low levels. At this point it still appears that there will be little impact from this feature on sensible weather aside from continued bouts of mid/high cloudiness, but this is something to keep an eye on through the next few days. Barring any surprises, expect showers to continue primarily across the typical windward and mauka areas through midweek, with some spillover into leeward due to the strength of the trades.