CLEX-9 October 23rd, 2001 Operations

Synopsis

• The CLEX-9 forecast team has decided to stand by all operations for Tuesday, October 23rd.
  
  
• Weather Forecast (made at 1500 MDT 10/22/01):

  
            FORECAST DISCUSSION:
  
            The subtropical jet and associated dry slot will continue to progress eastward 
            throughout the day and it it’s wake on Tuesday AM will be two major shortwaves 
            (subtropical s/w will be to east-southeast and a strong s/w and associated frontal 
            system to the northwest.)   These S/W’s have enough moisture to produce clouds of 
            interest for CLEX-9 operations.  The timing of PVA/moisture over LBF varies slightly 
            between the RUC and ETA by a few hours; so the early AM update will pin down the exact
            timing and adjust the takeoff time accordingly.
  
            OUTLOOK:
  
            Wednesday looks problematic due to Tuesday’s frontal passage and strong subsidence 
            aloft.  But, by Thursday strong 500mb winds will bring Pacific moisture around the 
            weak ridge over the Rockies.
  
  
            Jim/Don/Larry
  
    
  Morning Update (made at 0300 MDT 10/18/01): 
  
            CLEX will stand down today.
  
            Several bands of thick cirrus extend nne to ssw over eastern, central, and western 
            Wyoming.   Over the past 5 hours these bands have gone through a cycle of enhancement 
            and dissipation in direct concert with the appearance of radar echoes ... with little 
            cloud persisting away from the convective cells.    None of the reporting stations in 
            Wyoming have shown more than scattered cloud at 12K ft or below during the previous 
            6 hours except the few instances where precipitation was reported at the site.   The 
            ir loop indicates thick cirrus with tops at or above 30K feet in the vicinity of the 
            convective cells.
  
            All of the models we looked at this morning are in agreement with the movement of a 
            band of moisture, that is currently in westsern Wyoming, over the North Platte site by 
            18Z today.   It is likely that this band will manifest itself as a line of convective 
            activity - possibly a squall line - by early afternoon ... again, not a favorable 
            situation for CLEX sampling.
  
            Tomorrow and Thursday look like marginal days as well as the satellite loops show 
            decreasing moisture upstream, but the continuation of nwrly flow should make both days 
            worth looking at.
  
            In the longer term - the models are showing significant ridge building over the Pacific 
            NW and slowly move the ridge over the CLEX ops area by this weekend.   Surface temps 
            should push into the 80 degree range by the weekend - looks like extremely low 
            probabilities for CLEX ops from Friday through Sunday with the ridge progressing eastward 
            by early next week.
  
            Don/Larry
  
  

Sunrise Information for North Platte, NE

Sunrise   
                     Central Daylight Time          

        Begin civil twilight       7:36 a.m.                 
        Sunrise                    8:04 a.m.                 
        Sun transit                1:27 p.m.                 
        Sunset                     6:51 p.m.                 
        End civil twilight         7:19 p.m.               
          

Weather Details

1200Z 500 mb Map



1215Z GOES IR Image


 

Aircraft Operations

• No UW King Air Operations

North Platte, NE Ground Operations

• Ground Instrument Status: Everything working well
  
  
  

Data Collection Highlights:

• Summary: Nothing to report