After reviewing the ensemble forecast information provided, which of the following
do you think would be accurate statements for WFOs in the Mid-Atlantic states
(VA, MD, NJ, PA) at the end of the medium-range forecast period (7 days)? Check
all that apply, and click "DONE" when through.
The correct answers are a) and d). At this time range, we are
looking for large-scale indications for weather type, rather than specific
information for a forecast.
A) is true in that there are indicated a split flow at upper
and middle levels of the troposphere in western North America, with the flow
becoming confluent over the eastern U.S. and southeastern Canada. This flow
regime in the ensemble mean is a "heads-up" to watch for disturbances
in the northern and southern jet streams and their possible interaction.
D) is true because most ensemble members do not produce measurable
precipitation (<25% of 0.01" or greater) from the 00 and 12 UTC runs
at 7 days out from the time of interest.
C) is incorrect even though "no precipitation" is the
most likely outcome. Some ensemble members indicate that precipitation will
occur at day 7.
B) is incorrect because only one ensemble member of the 23 members
available indicated 0.5" or greater precipitation during the day 7 period.
Information can be seen in the lower left of the Probability of Exceedance
graphic.
Click MREF Forecasts Leading Up to
the Short-range in the menu to the left to continue.
