Portsmouth Naval Shipyard Probabilities (near MNPV2) 2018 adjusted tidal epoch
Exceedence Probability	Return Frequency	Ft./MLLW	Ft./MHHW	Ft. NAVD88	Last Occurred	MLLW Level (ft)	Event  (blue denotes Tropical)
1%	100 yr	8.82	5.68	7.32	11/12/2009	8.59	Nor'Ida of 2009
2%	50 year	8.36	5.25	6.89	9/18/2003	8.33	Hurricane Isabel (Irene 8.47 ft)
4%	25 year	7.70	4.59	6.23
10%	10 year	7.08	3.97	5.61	10/4/2015	7.01	Joaquin (offshore/subtropical)
20%	5 year	6.39	3.28	4.92	9/6/2019	6.21
50%	2 year	5.84	2.82	4.46	11/17/2019	5.88
99%	1 year	4.92	1.81	3.45
Purple Shading indicates "MAJOR" Flooding		Red Shading indicates "MODERATE Flooding				Orange Shading Indicates "MINOR" Flooding