The yellow shaded area represents the range of monthly mean values that have occurred from 1985 to 2008. The blue line shows the monthly mean values for each month over that same time period. The red line shows what the current years conditions are and how they compare to the range and the average values we’ve seen.

To convert temperature to Fahrenheit, use the conversion tool below.

2010 Surface Water Temperature
Patuxent River / Jack Bay (LE1.1)

Legend Range 1985 to 2008 2010 Mean

Surface Water Temperature (�F) Patuxent River / Jack Bay (LE1.1)
Month	Minimum	Mean	Maximum	2009	2010
January	33.80	39.07	45.32	39.74	37.94
February	33.26	39.08	46.04	34.70	34.52
March	41.36	45.18	49.46	43.88
April	51.53	55.86	60.17	55.31
May	61.16	66.36	74.21	65.30
June	70.43	75.15	79.61	75.74
July	77.45	81.55	86.99	78.71
August	76.55	81.16	85.82	83.03
September	71.24	75.74	79.88	75.56
October	59.18	65.46	70.88	69.26
November	43.70	52.86	59.18	58.10
December	33.80	44.69	55.58	51.62

NOTE: Results displayed are provisional and have not undergone full Quality Assurance procedures. Although Maryland DNR believes the data presented here are correct, we cannot guarantee their accuracy at this time.

Looks like it’ll be early to mid-May before I can start open water swims in the Patuxent river. A month before Eagleman 70.3?? That’ll work. (please no jellyfish, please no jellyfish)